Release 0.2.0-rc.4+git76-e9a24b1

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,52 @@ All notable changes to Housecarl are documented here. The format follows
 
 ### Added
 
+- **Sets from Jarl** ([docs/jarl.md](docs/jarl.md#sets-from-jarl)). A set
+  can hold the addresses of names in Jarl instead of listing them:
+  every A and AAAA record of each name, CNAMEs followed (within Jarl's
+  zones, in the same view), one view per name (`NAME@VIEW`; a name more
+  than one view covers must say which). housecarld reads them through
+  Jarl's API every `jarl.refresh` (a minute) and after each change, and
+  when they change applies the ruleset again, without a history entry
+  (audited as `set.jarl`). A set uses only the addresses `within` the
+  zones (their connected networks, which grow with the zone) and
+  networks it names; others are left out and warned of (`jarl_outside`).
+  While Jarl can't be read, sets keep the addresses they had, saved in
+  the database for restarts and in the boot ruleset (`jarl_unreachable`).
+  Names that give nothing say why (`jarl_name`: no record, a wildcard
+  only, a CNAME out of Jarl or in a loop, below a delegation, a secondary
+  zone, more than one view). `hc set add --jarl NAME@VIEW --within ZONE`,
+  `hc set jarl SET [--refresh]`; the kind "from Jarl" and Addresses… on
+  the Sets page; `GET /sets/{name}/jarl`, `POST /sets/{name}/jarl/refresh`.
+  Housecarl's Jarl token needs `records:read` for the zones.
+- An administrator can make an API token for another user in the web
+  UI: New token on the user's row under Users (the CLI's `hc token create
+  --user` and the API could already).
+- **Ban lists** ([docs/bans.md](docs/bans.md)). A program (Guard, which
+  reads logs, or fail2ban) bans an address, of every port or of some,
+  for a time; the ban list says what the address is kept from: the
+  firewall itself (`firewall`), some hosts behind it (`hosts`, port
+  forwards to them included), or `everything`. Bans are dropped ahead of
+  every rule, established connections too, and the banned address's
+  connections are closed. IPv6 addresses are banned by /64 (`group_v6`).
+  Never banned: inside networks, the firewall's own addresses, whoever
+  asks, and the list's `never`. Bans end by themselves, are cut to the
+  list's longest time, survive restarts and reboots, and are audited, but
+  aren't configuration (no history, probation or changesets). `hc
+  banlist`, `hc bans`, `hc ban`, `hc unban`; Traffic → Bans in the web UI;
+  `/banlists` and `/banlists/{ref}/bans` in the API; a `bans` grant that
+  can name lists (`bans:write:web`), in the `viewer` and `operator`
+  roles.
+- **A fail2ban action**, `contrib/fail2ban/action.d/housecarl.conf`
+  (installed under `/usr/share/doc/housecarl/contrib/`): fail2ban's bans
+  go into a ban list, with the jail's port and protocol.
+- **Failed logins in the journal.** A failed login and a refused API
+  token are logged (`msg="login failed" ip=… user=…`), for Guard and
+  fail2ban to act on.
+
+- **Quota usage as a share.** What a quota used shows its percentage
+  (`12.3 GB of 50.0 GB used (24%)`, each address's in the quota
+  dialog), on the Rules page, the dashboard and in `hc quotas`.
 - **Reset one address's quota, or give some back.** `hc rule
   reset-quota ID --address ADDR` starts only that device's allowance
   again; `--give 5gbytes` takes that much off what was used instead (one
@@ -78,6 +124,45 @@ All notable changes to Housecarl are documented here. The format follows
 
 ### Changed
 
+- Moving a rule several places is one change. The Rules page has a
+  **Move…** button that puts a rule before any other of its chain (or at
+  the end) at once, and in a changeset a move right after a move of the
+  same rule takes its place, so ↑ three times stages one operation (and
+  moving it back where it was takes the operation out).
+- Statistics' "Busiest rules" (the Statistics page, `hc stats`,
+  `GET /stats/summary`) lists only rules and NAT objects. Built-ins and
+  policies have their own list ("Built-ins and policies", `builtins` in
+  the API): the established built-in passes most of the traffic, so it
+  topped the list every time and made every rule's bar look empty.
+- `hc user delete` asks first, as every other delete does, and takes
+  `-y`/`--yes` not to; it deleted the user and their tokens at once.
+- The ruleset's diff (Changes, `hc changeset diff`, `--dry-run`) names
+  the chain each part is in on its `@@` line (`@@ -40,6 +40,8 @@ chain
+  forward`), as `git diff` names the function, so a rule added deep in a
+  long chain says whether it is in input, forward or output.
+- **History shows the ruleset's diff.** An entry's page (and `hc history
+  diff ID`, `GET /history/{id}/diff`) shows what the change did to the
+  ruleset, for entries made before this version too: the configuration
+  before and after it is got back from the current one and rendered by
+  this version.
+- Negating a match is said first: the zone, From and To fields (rules
+  and NAT) start with "any of" / "any but" instead of a checkbox under
+  the list, shown once the list has an entry, and an "any but" list is
+  marked with a red bar. An empty list is never saved as negated (it
+  matched everything anyway, but would have negated what was added to
+  it later).
+- docs/rules.md: "Matching everything but a few", on leaving some
+  addresses out with a zone and "any but", and what to do when the range
+  isn't a zone.
+- The rule dialog shows only the zone fields its chain can use: no
+  "Going out on" for input and early, no "Coming in on" for output
+  (they could only be refused). A zone left in a field the chain hides
+  isn't sent.
+- History lists a changed setting by its own fields
+  (`builtins.drop_invalid: false → true`), on the web page and in `hc
+  history show`, instead of the whole `builtins` before and after.
+- Set names starting with `ban_` are now reserved (`set_name_reserved`):
+  ban lists' sets use them.
 - **Rules read as a direction.** A match's zones are written `lan → wan`,
   `any but wan → any`, or with the firewall itself as the other end
   (`lan → firewall` in input, `firewall → wan` in output), instead of
@@ -87,6 +172,45 @@ All notable changes to Housecarl are documented here. The format follows
 
 ### Fixed
 
+- Link-local addresses (`fe80::/10`) are refused in the IPv6 antispoof
+  list and in your prefixes (`antispoof_link_local`). Dropping them on
+  external zones dropped the ISP's router adverts and DHCPv6 replies
+  before the built-ins could accept them: the IPv6 default route expired
+  and, later, the delegated prefix would have. A configuration saved
+  with one keeps being applied, but the next change is refused until it
+  is taken out. `hc import nft` leaves them out, with a note.
+- An IPv4-mapped prefix (`::ffff:0:0/96`) is refused with an error that
+  says so; it was refused as "has host bits set; the prefix is invalid
+  Prefix".
+- `hc forward show` shows the forward's hits and comment, and its
+  hairpin as `no`, `yes` or `yes, from …` (it printed `no -`).
+- A history entry's ruleset diff showed the object it changed as moved:
+  stepping back put the old form at the end of its list, so updating
+  one port forward (turning hairpin off) also showed its forward and
+  DNAT lines moving down. The diff is now only what the change did, and
+  its sides are named `before N` and `after N` instead of `now`.
+- Ruleset diffs numbered the hunks after one with a moved line too early
+  on the new side (`@@ -76,9 +74,9 @@` for `+76,9`), so the chain named
+  after `@@` could be the one before (`chain output` for a hunk in
+  `chain dstnat`). go-udiff miscounts them; Housecarl now numbers them
+  itself.
+- The dashboard's bar for a per-address quota showed only the busiest
+  address, so one address that used up its allowance filled it (100%).
+  The bar is now all the addresses together, and the dashboard and the
+  rule's quota line say how many addresses used theirs up.
+- Changing how a quota counts lost or muddled what it used: per address
+  to a total started at nothing, per source to per destination kept the
+  sources' use as if it were the destinations', and other groups left
+  the old entries behind. Now a total starts at the addresses' sum,
+  wider groups add up their addresses, and what can't be carried starts
+  again with a warning (`quota_restarts`) on the change.
+- What the quotas used is saved after every change, not only every five
+  minutes: a reboot soon after a change that counts a quota differently
+  could bring back its usage counted the old way.
+- Statistics' Quotas card linked every entry to the Rules page, not to
+  its rule; each now opens its rule, named. Per-address quotas were
+  missing from it (and from the `quota:rN` series): they count their
+  addresses' sum.
 - `hc stats top devices` listed each device twice (once for what it
   received, once for what it sent); it is one row with both again.
 - `hc rule add --before/--after/--first` made two changes (create at the

Makefile

@@ -112,6 +112,7 @@ install-files:
 	install -D -m 0644 CHANGELOG.md $(DESTDIR)$(DOCDIR)/CHANGELOG.md
 	install -d $(DESTDIR)$(DOCDIR)/docs
 	install -m 0644 docs/*.md $(DESTDIR)$(DOCDIR)/docs/
+	install -D -m 0644 contrib/fail2ban/action.d/housecarl.conf $(DESTDIR)$(DOCDIR)/contrib/fail2ban/action.d/housecarl.conf
 
 uninstall:
 	rm -f $(DESTDIR)$(BINDIR)/housecarld $(DESTDIR)$(BINDIR)/hc $(DESTDIR)$(UNITDIR)/housecarl.service \

README.md

@@ -53,6 +53,10 @@ table of its own.
   firewall you have, blocking nothing: its hits, log and tracer show what
   it would drop, so you see what switching over would break before you do
   ([docs/shadow.md](docs/shadow.md)).
+* **Ban lists for Guard and fail2ban.** A program on any machine bans an
+  address it caught misbehaving in its logs, and the ban list says what
+  that address is kept from: the firewall, some hosts, or everything
+  ([docs/bans.md](docs/bans.md)).
 * **Easy to watch.** A zone matrix of what is allowed between zones,
   statistics over time (traffic per zone and device, drops, the sources
   blocked most, connections; [docs/stats.md](docs/stats.md)), hits per rule, a live log of what was dropped and
@@ -107,6 +111,7 @@ The web UI is on `http://127.0.0.1:8070/` (see `listen` in
 * [install.md](docs/install.md): packages, building from source, first steps
 * [rules.md](docs/rules.md): zones, address sets, services, rules and the built-ins
 * [nat.md](docs/nat.md): port forwards, hairpin NAT, IPv6 pinholes, source NAT, redirects
+* [bans.md](docs/bans.md): ban lists, where Guard and fail2ban ban addresses
 * [import.md](docs/import.md): moving from an existing nftables ruleset
 * [shadow.md](docs/shadow.md): shadow mode, Housecarl beside your firewall, changing nothing
 * [operations.md](docs/operations.md): probation, the boot and its fallback, hits and the log, monitoring, backups, troubleshooting
@@ -123,14 +128,15 @@ The web UI is on `http://127.0.0.1:8070/` (see `listen` in
 
 ## Status
 
-Housecarl 0.1.1 is in testing (0.1.1-rc.10): zones, address sets and
+Housecarl 0.2.0 is in testing (0.2.0-rc.4+git76-e9a24b1): zones, address sets and
 services with ordered rules, IPv4 and IPv6, port forwards with hairpin NAT
 and IPv6 pinholes, source NAT and redirects, built-ins, probation for
 network changes (confirmed by the client that made them), the ruleset
 at boot with a fail-closed fallback, hits and the drop log, nftables
 import, changesets reviewed with the ruleset's diff (as in Jarl),
-bandwidth limits and quotas, shadow mode beside another firewall, a web
+bandwidth limits and quotas, shadow mode beside another firewall, ban
-UI, REST API and CLI.
+lists for Guard and fail2ban, sets of names from Jarl, a web UI, REST
+API and CLI.
 
 ## Licence
 

VERSION

@@ -1 +1 @@
-0.1.1-rc.10
+0.2.0-rc.4+git76-e9a24b1

cmd/hc/admin.go

@@ -66,6 +66,30 @@ func historyCmd() *cobra.Command {
 			})
 		},
 	})
+	cmd.AddCommand(&cobra.Command{
+		Use: "diff ID", Short: "Show what a change did to the ruleset", Args: cobra.ExactArgs(1),
+		Long: `Shows the ruleset's diff for a change: the configuration before and after
+it, rendered by this version of Housecarl.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var d struct {
+				Diff string `json:"diff"`
+			}
+			if err := c.Get(ctx(), "/history/"+args[0]+"/diff", nil, &d); err != nil {
+				return err
+			}
+			return output(d, func(w io.Writer) {
+				if d.Diff == "" {
+					fmt.Fprintln(w, "the ruleset didn't change")
+					return
+				}
+				printDiff(w, d.Diff)
+			})
+		},
+	})
 	cmd.AddCommand(&cobra.Command{
 		Use:   "undo ID",
 		Short: "Undo a change",
@@ -88,11 +112,13 @@ change touched has changed since; undo the later changes first.`,
 }
 
 // diffJSON lists the fields that differ between two versions of an
-// object: "name: office -> lab".
+// object: "name: office -> lab". An object within (settings' builtins)
+// is compared field by field: "builtins.drop_invalid: false -> true".
 func diffJSON(before, after json.RawMessage) []string {
 	var a, b map[string]any
 	json.Unmarshal(before, &a)
 	json.Unmarshal(after, &b)
+	a, b = flatten(a, "", map[string]any{}), flatten(b, "", map[string]any{})
 	keys := map[string]bool{}
 	for k := range a {
 		keys[k] = true
@@ -132,6 +158,19 @@ func diffJSON(before, after json.RawMessage) []string {
 	return out
 }
 
+// flatten lifts the fields of objects within m to dotted keys; lists
+// stay whole.
+func flatten(m map[string]any, prefix string, out map[string]any) map[string]any {
+	for k, v := range m {
+		if o, ok := v.(map[string]any); ok && len(o) > 0 {
+			flatten(o, prefix+k+".", out)
+		} else {
+			out[prefix+k] = v
+		}
+	}
+	return out
+}
+
 func whoamiCmd() *cobra.Command {
 	return &cobra.Command{
 		Use: "whoami", Short: "Show who you are to the server", Args: cobra.NoArgs,
@@ -310,9 +349,13 @@ operator, log) or grants such as --grant config:read --grant sets:write:guests.
 	f.BoolVar(&enable, "enable", false, "enable the user again")
 	f.StringVar(&comment, "comment", "", "a comment")
 	cmd.AddCommand(update)
-	cmd.AddCommand(&cobra.Command{
+	var yes bool
+	del := &cobra.Command{
 		Use: "delete USER", Short: "Delete a user and their tokens", Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
+			if !confirm(fmt.Sprintf("Delete user %s and their tokens?", args[0]), yes) {
+				return fmt.Errorf("not deleted")
+			}
 			id, err := userID(args[0])
 			if err != nil {
 				return err
@@ -326,7 +369,9 @@ operator, log) or grants such as --grant config:read --grant sets:write:guests.
 			}
 			return nil
 		},
-	})
+	}
+	del.Flags().BoolVarP(&yes, "yes", "y", false, "don't ask")
+	cmd.AddCommand(del)
 	return cmd
 }
 

cmd/hc/bans.go

@@ -0,0 +1,313 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"net/url"
+	"strconv"
+	"strings"
+
+	"github.com/spf13/cobra"
+
+	"housecarl/internal/api"
+	"housecarl/internal/model"
+)
+
+// ---- ban lists (docs/bans.md)
+
+// banTime writes a ban list's time setting: 0 is the default, -1 none.
+func banTime(n int, def string) string {
+	switch {
+	case n < 0:
+		return "no limit"
+	case n == 0:
+		return def + " (default)"
+	}
+	return fmtSeconds(n)
+}
+
+// parseBanTime reads a time flag: a duration, or "none" (-1) for no
+// limit.
+func parseBanTime(s string) (int, error) {
+	if strings.EqualFold(s, "none") || s == "-1" {
+		return -1, nil
+	}
+	return parseSeconds(s)
+}
+
+func banlistCmd() *cobra.Command {
+	cmd := &cobra.Command{Use: "banlist", Aliases: []string{"banlists"}, Short: "Ban lists: where Guard and fail2ban ban addresses"}
+	cmd.AddCommand(&cobra.Command{
+		Use: "list", Short: "List the ban lists", Args: cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			bs, err := get[[]model.BanList]("/banlists", nil)
+			if err != nil {
+				return err
+			}
+			bans, _ := get[[]model.Ban]("/bans", nil)
+			count := map[int64]int{}
+			for _, b := range bans {
+				count[b.ListID]++
+			}
+			return output(bs, func(w io.Writer) {
+				fmt.Fprintln(w, "NAME\tSCOPE\tHOSTS\tBANS\tCOMMENT")
+				for _, b := range bs {
+					scope := b.Scope
+					if b.Disabled {
+						scope += " (disabled)"
+					}
+					fmt.Fprintf(w, "%s\t%s\t%s\t%d\t%s\n", b.Name, scope, list(b.Hosts), count[b.ID], b.Comment)
+				}
+			})
+		},
+	})
+	cmd.AddCommand(showCmd("banlists", "banlist", func(w io.Writer, b model.BanList) {
+		fmt.Fprintf(w, "Name:\t%s\nScope:\t%s\n", b.Name, b.Scope)
+		if len(b.Hosts) > 0 {
+			fmt.Fprintf(w, "Hosts:\t%s\n", list(b.Hosts))
+		}
+		fmt.Fprintf(w, "Never:\t%s\n", list(b.Never))
+		fmt.Fprintf(w, "Ban time:\t%s\nLongest:\t%s\n", banTime(b.DefaultTime, "1h"), banTime(b.MaxTime, "7d"))
+		fmt.Fprintf(w, "Most bans:\t%d\nIPv6 banned by:\t/%d\n", b.Entries(), b.V6Group())
+		if b.Disabled {
+			fmt.Fprintln(w, "Disabled:\tyes")
+		}
+		if b.Comment != "" {
+			fmt.Fprintf(w, "Comment:\t%s\n", b.Comment)
+		}
+	}))
+	var scope, comment, banT, maxT string
+	var hosts, never []string
+	var entries, group int
+	var disabled bool
+	setFields := func(fl interface{ Changed(string) bool }, p patch) error {
+		if fl.Changed("scope") {
+			p["scope"] = scope
+		}
+		if fl.Changed("host") {
+			p["hosts"] = hosts
+		}
+		if fl.Changed("never") {
+			p["never"] = never
+		}
+		for _, t := range []struct{ flag, field, v string }{{"time", "default_time", banT}, {"max-time", "max_time", maxT}} {
+			if fl.Changed(t.flag) {
+				n, err := parseBanTime(t.v)
+				if err != nil {
+					return err
+				}
+				p[t.field] = n
+			}
+		}
+		if fl.Changed("max-entries") {
+			p["max_entries"] = entries
+		}
+		if fl.Changed("group-v6") {
+			p["group_v6"] = group
+		}
+		if fl.Changed("comment") {
+			p["comment"] = comment
+		}
+		if fl.Changed("disabled") {
+			p["disabled"] = disabled
+		}
+		return nil
+	}
+	flags := func(c *cobra.Command) {
+		f := c.Flags()
+		f.StringVar(&scope, "scope", "", "what bans keep addresses from: firewall, hosts or everything")
+		f.StringArrayVar(&hosts, "host", nil, "scope hosts: a machine's address, or a set (repeat)")
+		f.StringArrayVar(&never, "never", nil, "an address, prefix or set never banned (repeat)")
+		f.StringVar(&banT, "time", "", "a ban's length when none is asked for (default 1h)")
+		f.StringVar(&maxT, "max-time", "", "the longest ban (default 7d; none for no limit)")
+		f.IntVar(&entries, "max-entries", 0, "the most bans the list holds (default 10000)")
+		f.IntVar(&group, "group-v6", 0, "IPv6 prefix length banned for an address (default 64)")
+		f.StringVar(&comment, "comment", "", "a comment")
+		f.BoolVar(&disabled, "disabled", false, "the list's bans aren't in force")
+	}
+	add := &cobra.Command{
+		Use: "add NAME", Short: "Add a ban list", Args: cobra.ExactArgs(1),
+		Long: `Adds a ban list. A program bans an address into it (Guard, fail2ban's
+housecarl action, hc ban), and the list says what that address is kept
+from:
+
+  hc banlist add router --scope firewall                  # the firewall itself
+  hc banlist add web --scope hosts --host 10.0.10.57 --host 2001:db8:10::57
+  hc banlist add edge --scope everything --never trusted
+
+Give the program a token for its list alone:
+
+  hc user add guard-web --no-password --grant bans:write:web
+  hc token create web1 --user guard-web     # as root on the firewall`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			p := patch{"name": args[0]}
+			if err := setFields(cmd.Flags(), p); err != nil {
+				return err
+			}
+			return change("POST", "/banlists", p)
+		},
+	}
+	flags(add)
+	cmd.AddCommand(add)
+	update := &cobra.Command{
+		Use: "update BANLIST", Short: "Change a ban list", Args: cobra.ExactArgs(1),
+		Long: `Changes a ban list; --host and --never replace the lists. A ban list
+can't be renamed: tokens and programs know it by its name.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			p := patch{}
+			if err := setFields(cmd.Flags(), p); err != nil {
+				return err
+			}
+			return change("PATCH", objPath("banlists", args[0]), p)
+		},
+	}
+	flags(update)
+	cmd.AddCommand(update)
+	cmd.AddCommand(deleteCmd("banlists", "banlist"))
+	return cmd
+}
+
+// bansCmd lists the active bans.
+func bansCmd() *cobra.Command {
+	return &cobra.Command{
+		Use: "bans [BANLIST]", Short: "List the active bans", Args: cobra.MaximumNArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			path := "/bans"
+			if len(args) == 1 {
+				path = objPath("banlists", args[0]) + "/bans"
+			}
+			bans, err := get[[]model.Ban](path, nil)
+			if err != nil {
+				return err
+			}
+			return output(bans, func(w io.Writer) {
+				fmt.Fprintln(w, "ID\tLIST\tADDRESS\tPORT\tENDS IN\tBY\tSOURCE\tREASON")
+				for _, b := range bans {
+					port := "all"
+					if b.Protocol != "" {
+						port = fmt.Sprintf("%s/%d", b.Protocol, b.Port)
+					}
+					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\t%s\t%s\t%s\n", b.ID, b.List, b.Address, port, fmtSeconds(b.Timeout), b.Who, orDash(b.Source), orDash(clipText(b.Reason, 60)))
+				}
+			})
+		},
+	}
+}
+
+func clipText(s string, n int) string {
+	if len(s) > n {
+		return s[:n-1] + "…"
+	}
+	return s
+}
+
+// banCmd bans an address by hand.
+func banCmd() *cobra.Command {
+	var tcp, udp []string
+	var t, reason string
+	cmd := &cobra.Command{
+		Use: "ban BANLIST ADDRESS", Short: "Ban an address", Args: cobra.ExactArgs(2),
+		Long: `Bans an address in a ban list: every port, or with --tcp and --udp some
+(numbers or service names). IPv6 addresses are banned with the list's
+grouping (a /64 unless set otherwise).
+
+  hc ban edge 203.0.113.9 --time 1d
+  hc ban web 203.0.113.9 --tcp ssh --tcp 8443 --reason "tried passwords"`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			in := api.BanInput{Address: args[1], Reason: reason, Source: "hc"}
+			if t != "" {
+				n, err := parseBanTime(t)
+				if err != nil {
+					return err
+				}
+				in.Time = n
+			}
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var out api.BanResult
+			do := func(proto string, ports []string) error {
+				in.Protocol = proto
+				in.Ports = nil
+				if len(ports) > 0 {
+					in.Ports = []byte(strconv.Quote(strings.Join(ports, ",")))
+				}
+				var res api.BanResult
+				if err := c.Do(ctx(), "POST", objPath("banlists", args[0])+"/bans", nil, in, &res); err != nil {
+					return err
+				}
+				out.Bans = append(out.Bans, res.Bans...)
+				out.Closed += res.Closed
+				return nil
+			}
+			switch {
+			case len(tcp) == 0 && len(udp) == 0:
+				err = do("", nil)
+			default:
+				if len(tcp) > 0 {
+					err = do("tcp", tcp)
+				}
+				if err == nil && len(udp) > 0 {
+					err = do("udp", udp)
+				}
+			}
+			if err != nil {
+				return err
+			}
+			return output(out, func(w io.Writer) {
+				for _, b := range out.Bans {
+					what := "banned"
+					if b.Existing {
+						what = "renewed"
+					}
+					port := "every port"
+					if b.Protocol != "" {
+						port = fmt.Sprintf("%s/%d", b.Protocol, b.Port)
+					}
+					ends := "never ends"
+					if b.Timeout > 0 {
+						ends = "ends in " + fmtSeconds(b.Timeout)
+					}
+					fmt.Fprintf(w, "%s %s, %s, in %s (%s)\n", what, b.Address, port, b.List, ends)
+				}
+				if out.Closed > 0 {
+					fmt.Fprintf(w, "%d connections closed\n", out.Closed)
+				}
+			})
+		},
+	}
+	f := cmd.Flags()
+	f.StringArrayVar(&tcp, "tcp", nil, "ban only this TCP port or service (repeat)")
+	f.StringArrayVar(&udp, "udp", nil, "ban only this UDP port or service (repeat)")
+	f.StringVar(&t, "time", "", "how long (1h, 7d; default the list's; none for ever, if the list allows)")
+	f.StringVar(&reason, "reason", "", "why, for the record")
+	return cmd
+}
+
+// unbanCmd lifts bans: by ID, or every ban of an address.
+func unbanCmd() *cobra.Command {
+	return &cobra.Command{
+		Use: "unban BANLIST ADDRESS|ID", Short: "Lift a ban, or all of an address's", Args: cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			path, query := objPath("banlists", args[0])+"/bans", url.Values{}
+			if _, err := strconv.ParseInt(args[1], 10, 64); err == nil {
+				path += "/" + args[1]
+			} else {
+				query.Set("address", args[1])
+			}
+			var out map[string]int
+			if err := c.Do(ctx(), "DELETE", path, query, nil, &out); err != nil {
+				return err
+			}
+			if !flagQuiet {
+				fmt.Printf("%d bans lifted\n", out["removed"])
+			}
+			return nil
+		},
+	}
+}

cmd/hc/firewall.go

@@ -322,9 +322,13 @@ func quotasCmd() *cobra.Command {
 					if q.Quota.PerSource || q.Quota.PerDestination {
 						of += " each"
 					}
-					fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", q.Rule, humanBytes(q.Used), of, resets, next)
+					used := humanBytes(q.Used)
+					if !q.Quota.PerSource && !q.Quota.PerDestination {
+						used += " (" + percent(q.Used, q.Quota.Bytes) + ")"
+					}
+					fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\n", q.Rule, used, of, resets, next)
 					for _, a := range q.Addresses {
-						fmt.Fprintf(w, "  %s\t%s\t\t\t\n", named(names, a.Address, a.Address), humanBytes(a.Used))
+						fmt.Fprintf(w, "  %s\t%s (%s)\t\t\t\n", named(names, a.Address, a.Address), humanBytes(a.Used), percent(a.Used, q.Quota.Bytes))
 					}
 				}
 			})
@@ -332,6 +336,17 @@ func quotasCmd() *cobra.Command {
 	}
 }
 
+// percent writes used as a share of total: "25%", "<1%" for a little.
+func percent(used, total int64) string {
+	if total <= 0 || used <= 0 {
+		return "0%"
+	}
+	if used*100 < total {
+		return "<1%"
+	}
+	return fmt.Sprintf("%d%%", used*100/total)
+}
+
 func logCmd() *cobra.Command {
 	var follow bool
 	var limit int

cmd/hc/main.go

@@ -192,7 +192,7 @@ Exit codes: 0 ok, 1 error, 3 not authenticated or not allowed, 4 not found,
 			root.AddCommand(c)
 		}
 	}
-	add("fw", statusCmd(), zoneCmd(), setCmd(), serviceCmd(), ruleCmd(), forwardCmd(), snatCmd(), redirectCmd(), settingsCmd(),
+	add("fw", statusCmd(), zoneCmd(), setCmd(), serviceCmd(), ruleCmd(), forwardCmd(), snatCmd(), redirectCmd(), banlistCmd(), bansCmd(), banCmd(), unbanCmd(), settingsCmd(),
 		rulesetCmd(), countersCmd(), quotasCmd(), logCmd(), connectionsCmd(), traceCmd(), matrixCmd(), statsCmd(), interfaceCmd())
 	add("changes", changesetCmd(), confirmCmd(), rollbackCmd(), historyCmd(), importCmd(), takeoverCmd())
 	add("admin", whoamiCmd(), userCmd(), tokenCmd(), passwordCmd(), certCmd(), auditCmd(), configCmd())

cmd/hc/main_test.go

@@ -53,6 +53,11 @@ func TestLimitAndDescribe(t *testing.T) {
 			t.Errorf("describe(%+v, %s) = %q, want %q", c.m, c.chain, got, c.want)
 		}
 	}
+	for used, want := range map[int64]string{0: "0%", 5: "<1%", 250: "25%", 1000: "100%", 1300: "130%"} {
+		if got := percent(used, 1000); got != want {
+			t.Errorf("percent(%d, 1000) = %q, want %q", used, got, want)
+		}
+	}
 	if got := editList([]string{"a", "b", "c"}, []string{"d"}, []string{"b"}); len(got) != 3 || got[1] != "c" || got[2] != "d" {
 		t.Errorf("editList: %v", got)
 	}

cmd/hc/objects.go

@@ -271,6 +271,9 @@ func setCmd() *cobra.Command {
 				fmt.Fprintln(w, "NAME\tENTRIES\tCOMMENT")
 				for _, s := range ss {
 					entries := list(s.Entries)
+					if s.Jarl != nil {
+						entries = "from Jarl: " + strings.Join(jarlNames(s.Jarl), ", ")
+					}
 					if s.Dynamic {
 						entries = "dynamic"
 						if s.Timeout > 0 {
@@ -290,6 +293,11 @@ func setCmd() *cobra.Command {
 				fmt.Fprintf(w, "Timeout:\t%s\n", fmtSeconds(s.Timeout))
 			}
 		}
+		if s.Jarl != nil {
+			fmt.Fprintf(w, "From Jarl:\t%s\n", strings.Join(jarlNames(s.Jarl), ", "))
+			fmt.Fprintf(w, "Within:\t%s\n", strings.Join(s.Jarl.Within, ", "))
+			fmt.Fprintf(w, "Addresses:\thc set jarl %s\n", s.Name)
+		}
 		for i, e := range s.Entries {
 			label := ""
 			if i == 0 {
@@ -303,18 +311,29 @@ func setCmd() *cobra.Command {
 	}))
 	var dynamic bool
 	var timeout, comment string
+	var jarlN, within []string
 	add := &cobra.Command{
 		Use: "add NAME [ENTRY...]", Short: "Add a set", Args: cobra.MinimumNArgs(1),
 		Long: `Adds a set of addresses, prefixes and ranges, IPv4 and IPv6 mixed:
 
   hc set add trusted 192.168.1.0/24 192.168.2.0/24 2001:db8:1::/64
   hc set add guests --dynamic --timeout 24h
+  hc set add nas --jarl nas.example.com@internal --within lan
 
 A dynamic set takes entries at run time, each with its own timeout ('hc
 set entries', or the API with a token for that set alone: a captive
-portal's signed-in clients).`,
+portal's signed-in clients).
+
+A Jarl set holds the addresses of names in Jarl (their A and AAAA
+records, CNAMEs followed), read again every minute. --jarl takes
+NAME@VIEW, or NAME when only one view has it; --within says where its
+addresses may be (zones: their connected networks; or networks), and the
+others are left out ('hc set jarl NAME' shows them). docs/jarl.md.`,
 		RunE: func(cmd *cobra.Command, args []string) error {
 			s := model.AddressSet{Name: args[0], Entries: args[1:], Dynamic: dynamic, Comment: comment}
+			if len(jarlN) > 0 || len(within) > 0 {
+				s.Jarl = jarlSource(jarlN, within)
+			}
 			if timeout != "" {
 				n, err := parseSeconds(timeout)
 				if err != nil {
@@ -327,6 +346,8 @@ portal's signed-in clients).`,
 	}
 	add.Flags().BoolVar(&dynamic, "dynamic", false, "entries are added at run time")
 	add.Flags().StringVar(&timeout, "timeout", "", "a dynamic set's default entry lifetime (1h, 7d)")
+	add.Flags().StringArrayVar(&jarlN, "jarl", nil, "a name in Jarl whose addresses the set holds: NAME or NAME@VIEW (repeat)")
+	add.Flags().StringArrayVar(&within, "within", nil, "a Jarl set: a zone or network its addresses must lie in (repeat)")
 	add.Flags().StringVar(&comment, "comment", "", "a comment")
 	cmd.AddCommand(add)
 	var addE, removeE, entries []string
@@ -350,6 +371,23 @@ portal's signed-in clients).`,
 				}
 				p["entries"] = editList(cur, addE, removeE)
 			}
+			if fl.Changed("jarl") || fl.Changed("within") {
+				s, err := get[model.AddressSet](objPath("sets", args[0]), nil)
+				if err != nil {
+					return err
+				}
+				j := s.Jarl
+				if j == nil {
+					j = &model.JarlSource{}
+				}
+				if fl.Changed("jarl") {
+					j.Names = jarlSource(jarlN, nil).Names
+				}
+				if fl.Changed("within") {
+					j.Within = within
+				}
+				p["jarl"] = j
+			}
 			if fl.Changed("timeout") {
 				n, err := parseSeconds(timeout)
 				if err != nil {
@@ -371,11 +409,104 @@ portal's signed-in clients).`,
 	f.StringArrayVar(&addE, "add", nil, "add an entry")
 	f.StringArrayVar(&removeE, "remove", nil, "remove an entry")
 	f.StringVar(&timeout, "timeout", "", "a dynamic set's default entry lifetime")
+	f.StringArrayVar(&jarlN, "jarl", nil, "replace a Jarl set's names: NAME or NAME@VIEW (repeat)")
+	f.StringArrayVar(&within, "within", nil, "replace where a Jarl set's addresses may be: zones, networks (repeat)")
 	f.StringVar(&comment, "comment", "", "a comment")
 	f.StringVar(&name, "name", "", "a new name")
 	cmd.AddCommand(update)
 	cmd.AddCommand(deleteCmd("sets", "set"))
 	cmd.AddCommand(entriesCmd())
+	cmd.AddCommand(jarlCmd())
+	return cmd
+}
+
+func jarlSource(names, within []string) *model.JarlSource {
+	j := &model.JarlSource{Names: []model.JarlName{}, Within: within}
+	for _, n := range names {
+		j.Names = append(j.Names, model.ParseJarlName(n))
+	}
+	return j
+}
+
+func jarlNames(j *model.JarlSource) []string {
+	var out []string
+	for _, n := range j.Names {
+		out = append(out, n.String())
+	}
+	return out
+}
+
+// jarlCmd shows what a Jarl set holds, name by name.
+func jarlCmd() *cobra.Command {
+	var refresh bool
+	cmd := &cobra.Command{Use: "jarl SET", Short: "What a Jarl set holds: each name's addresses in Jarl, and which are used", Args: cobra.ExactArgs(1),
+		Long: `Shows a Jarl set's names with the addresses Jarl gives them (CNAMEs
+followed), whether each is used or why it is left out (not within the
+set's zones and networks), and when Jarl last answered. --refresh reads
+Jarl first.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var js api.JarlSet
+			if refresh {
+				err = c.Do(ctx(), "POST", objPath("sets", args[0])+"/jarl/refresh", nil, nil, &js)
+			} else {
+				err = c.Do(ctx(), "GET", objPath("sets", args[0])+"/jarl", nil, nil, &js)
+			}
+			if err != nil {
+				return err
+			}
+			return output(js, func(w io.Writer) {
+				if !js.Configured {
+					fmt.Fprintln(w, "Jarl isn't configured (jarl.server in housecarl.yaml): the set keeps the addresses it last had.")
+				}
+				if js.Error != "" {
+					fmt.Fprintf(w, "Reading Jarl failed: %s (the set keeps the addresses it had)\n", js.Error)
+				}
+				fmt.Fprintf(w, "Set:\t%s\n", js.Set)
+				fmt.Fprintf(w, "Within:\t%s\n", strings.Join(js.Within, ", "))
+				fmt.Fprintf(w, "Holds:\t%s\n", list(js.Entries))
+				if js.Read != nil {
+					fmt.Fprintf(w, "Jarl read:\t%s\n", js.Read.Local().Format("2006-01-02 15:04:05"))
+				}
+				fmt.Fprintln(w)
+				fmt.Fprintln(w, "NAME\tVIEW\tADDRESS\tUSED")
+				for _, n := range js.Names {
+					label := n.Name
+					if len(n.Chain) > 0 {
+						label += " → " + strings.Join(n.Chain, " → ")
+					}
+					view := n.View
+					if view == "" {
+						view = n.Found
+					}
+					if view == "" {
+						view = "-"
+					}
+					switch {
+					case n.Problem != "":
+						fmt.Fprintf(w, "%s\t%s\t-\tno: %s\n", label, view, n.Problem)
+					case len(n.Addresses) == 0 && n.Error != "":
+						fmt.Fprintf(w, "%s\t%s\t-\tnot read: %s\n", label, view, n.Error)
+					case len(n.Addresses) == 0:
+						fmt.Fprintf(w, "%s\t%s\t-\tnot read yet\n", label, view)
+					}
+					for _, a := range n.Addresses {
+						used := "yes"
+						if !a.Used {
+							used = "no: " + a.Why
+						}
+						fmt.Fprintf(w, "%s\t%s\t%s\t%s\n", label, view, a.Address, used)
+					}
+					if n.Error != "" && len(n.Addresses) > 0 {
+						fmt.Fprintf(w, "%s\t%s\t\t(the last read failed: %s; these are from before)\n", label, view, n.Error)
+					}
+				}
+			})
+		}}
+	cmd.Flags().BoolVar(&refresh, "refresh", false, "read Jarl now")
 	return cmd
 }
 

cmd/hc/rules.go

@@ -605,7 +605,16 @@ func forwardCmd() *cobra.Command {
 		if f.ToPort != "" {
 			fmt.Fprintf(w, "To port:\t%s\n", f.ToPort)
 		}
-		fmt.Fprintf(w, "To (IPv6):\t%s\nFrom:\t%s\nHairpin:\t%s %s\n", orDash(f.To6), list(f.Sources), yesNo(f.Hairpin), list(f.HairpinSources))
+		hairpin := yesNo(f.Hairpin)
+		if f.Hairpin && len(f.HairpinSources) > 0 {
+			hairpin += ", from " + list(f.HairpinSources)
+		}
+		fmt.Fprintf(w, "To (IPv6):\t%s\nFrom:\t%s\nHairpin:\t%s\n", orDash(f.To6), list(f.Sources), hairpin)
+		if f.Comment != "" {
+			fmt.Fprintf(w, "Comment:\t%s\n", f.Comment)
+		}
+		cs := counters()
+		fmt.Fprintf(w, "Hits:\t%s\n", hits(cs, fmt.Sprintf("f%d", f.ID), fmt.Sprintf("f%d-6", f.ID)))
 	}))
 	var pf model.PortForward
 	var to string

cmd/hc/stats.go

@@ -33,6 +33,7 @@ type statSummary struct {
 	Drops           int64         `json:"drops"`
 	DropsByChain    []statEntry   `json:"drops_by_chain"`
 	Rules           []statEntry   `json:"rules"`
+	BuiltIns        []statEntry   `json:"builtins"`
 	PeakConnections int64         `json:"peak_connections"`
 	ConntrackMax    int64         `json:"conntrack_max"`
 	BlockedSources  []statEntry   `json:"blocked_sources"`
@@ -136,6 +137,7 @@ func printSummary(w io.Writer, s statSummary) {
 	}
 	packets := func(n int64) string { return humanCount(uint64(n)) + " packets" }
 	list("Busiest rules:", s.Rules, packets)
+	list("Built-ins and policies:", s.BuiltIns, packets)
 	list("Blocked most (logged drops):", s.BlockedSources, packets)
 	list("What they tried:", s.BlockedPorts, packets)
 	list("Devices, sent:", s.DevicesUp, humanBytes)

cmd/housecarld/main.go

@@ -30,6 +30,7 @@ import (
 	"housecarl/internal/engine"
 	"housecarl/internal/hostif"
 	"housecarl/internal/jarl"
+	"housecarl/internal/jarlsets"
 	"housecarl/internal/linkwatch"
 	"housecarl/internal/model"
 	"housecarl/internal/names"
@@ -156,7 +157,8 @@ func serveCmd() *cobra.Command {
 			host := &hostif.Host{}
 			eng.Env = hostEnv(host)
 			fw := &nft.Firewall{Runner: &nft.Runner{Command: nft.Wrapper()}, Interfaces: host.Exists, BootFile: a.cfg.Ruleset,
-				Shadow: a.cfg.Shadow.Enabled, ShadowBefore: a.cfg.Shadow.Position == config.ShadowBefore}
+				Shadow: a.cfg.Shadow.Enabled, ShadowBefore: a.cfg.Shadow.Position == config.ShadowBefore,
+				Bans: func() []render.Ban { return server.ActiveBans(context.Background(), a.store) }}
 			eng.Firewall = fw
 			if fw.Shadow {
 				a.log.Warn("shadow mode: Housecarl's ruleset is loaded but blocks, rejects and translates nothing; the other firewall decides (docs/shadow.md)", "position", a.cfg.Shadow.Position)
@@ -164,19 +166,43 @@ func serveCmd() *cobra.Command {
 			for _, p := range eng.Problems() {
 				a.log.Warn("configuration problem: "+p.Message, "object", p.Object, "code", p.Code)
 			}
-			var acme *certs.Manager
+			var jc *jarl.Client
-			if a.cfg.TLS.ACME.Domain != "" {
+			if a.cfg.Jarl.Enabled() {
 				tok, err := a.cfg.Jarl.ReadToken()
 				if err != nil {
 					return err
 				}
-				jc, err := jarl.New(a.cfg.Jarl.Server, tok, a.cfg.Jarl.CACert, a.cfg.Jarl.Insecure)
+				if jc, err = jarl.New(a.cfg.Jarl.Server, tok, a.cfg.Jarl.CACert, a.cfg.Jarl.Insecure); err != nil {
-				if err != nil {
 					return err
 				}
+			}
+			var acme *certs.Manager
+			if a.cfg.TLS.ACME.Domain != "" {
+				if jc == nil {
+					return errors.New("tls.acme needs Jarl: set jarl.server and its token (docs/certificates.md)")
+				}
 				acme = certs.New(ctx, certs.Config{ACME: a.cfg.TLS.ACME, Version: version.Short()}, jc, a.store, a.log)
 				go acme.Run(ctx)
 			}
+			// The sets whose addresses come from Jarl: what was last read
+			// is put in force at once, Jarl is read again soon after.
+			jarlSets := &jarlsets.Resolver{Interval: time.Duration(a.cfg.Jarl.Refresh), State: eng.State, Log: a.log,
+				Apply: func(ctx context.Context) error {
+					if err := eng.ApplyCurrent(ctx); err != nil {
+						return err
+					}
+					return fw.SaveBoot(eng.State())
+				},
+				Audit: func(ctx context.Context, set, detail string) {
+					eng.Audit(ctx, &auth.Principal{Method: "jarl"}, "set.jarl", set, "success", detail)
+				},
+				Load: func(ctx context.Context) (string, error) { return a.store.GetMeta(ctx, jarlsets.MetaKey) },
+				Save: func(ctx context.Context, v string) error { return a.store.SetMeta(ctx, jarlsets.MetaKey, v) }}
+			if jc != nil {
+				jarlSets.Source = jc
+			}
+			jarlSets.Restore(ctx)
+			fw.JarlSets = jarlSets
 			var resolver *names.Resolver
 			if a.cfg.Names.Enabled {
 				resolver = names.New(a.cfg.Names.Resolver, time.Duration(a.cfg.Names.Cache))
@@ -185,8 +211,9 @@ func serveCmd() *cobra.Command {
 				Listen: a.cfg.Listen, TLSCertFile: a.cfg.TLS.CertFile, TLSKeyFile: a.cfg.TLS.KeyFile, TrustedProxies: a.cfg.Proxies(),
 				SessionLifetime: time.Duration(a.cfg.Session.Lifetime), SessionIdle: time.Duration(a.cfg.Session.IdleTimeout),
 				CookieSecure: a.cfg.Session.CookieSecure, Socket: a.cfg.Socket, ACME: acme,
-				Shadow: a.cfg.Shadow.Enabled, ShadowPosition: a.cfg.Shadow.Position, Names: resolver,
+				Shadow: a.cfg.Shadow.Enabled, ShadowPosition: a.cfg.Shadow.Position, Names: resolver, JarlSets: jarlSets,
 			}, eng, fw, host, a.log, web.FS())
+			jarlSets.Connected = srv.Connected
 			// Put the ruleset in force: what was on probation when
 			// housecarld stopped is rolled back first. An empty
 			// configuration applies nothing: its default policies would
@@ -216,6 +243,7 @@ func serveCmd() *cobra.Command {
 			go func() {
 				err := linkwatch.Watch(ctx, func() {
 					host.Forget()
+					jarlSets.Kick() // a zone's networks may have changed
 					if !fw.FlowtableStale(eng.State()) {
 						return
 					}
@@ -252,6 +280,7 @@ func serveCmd() *cobra.Command {
 					}
 				}()
 			}
+			go jarlSets.Run(ctx)
 			go nflog.Listen(ctx, render.LogGroup, a.log, srv.LogPacket)
 			go srv.RunQuotas(ctx)
 			srv.SetConntrack(conntrack.Client{})

contrib/fail2ban/action.d/housecarl.conf

@@ -0,0 +1,52 @@
+# Housecarl's action for fail2ban: a ban goes into a Housecarl ban list,
+# and the list says what the banned address is kept from (the firewall
+# itself, some hosts behind it, or everything). See docs/bans.md.
+#
+# Copy this file to /etc/fail2ban/action.d/housecarl.conf, make a ban
+# list and a token for it alone on the firewall:
+#
+#   hc banlist add web --scope hosts --host 10.0.10.57
+#   hc user add f2b-web --no-password --grant bans:write:web
+#   hc token create web --user f2b-web        # as root on the firewall
+#
+# put the token in /etc/fail2ban/housecarl.token (mode 0600), and use it
+# in a jail:
+#
+#   [sshd]
+#   enabled = true
+#   action  = housecarl[list=web, url="https://router.lan:8070"]
+#
+# The jail's port and protocol go along: port = ssh bans only tcp/22;
+# fail2ban's default (0:65535) bans every port. IPv6 addresses are banned
+# with the list's grouping (a /64 unless set otherwise). Housecarl never
+# bans inside networks, its own addresses or the list's "never".
+#
+# On the firewall itself, the local socket works too, still with the
+# token: url = http://localhost, curlopts = --unix-socket
+# /run/housecarl/housecarl.sock.
+
+[Definition]
+
+actionstart =
+actionstop =
+actioncheck =
+
+# A ban renews one already there; a bantime of -1 is the list's longest.
+actionban = <_curl> -f -X POST -H "Content-Type: application/json" "<url>/api/v1/banlists/<list>/bans"
+            -d '{"address": "<ip>", "protocol": "<protocol>", "ports": "<port>", "time": <bantime>, "source": "fail2ban/<name>"}'
+
+# A ban Housecarl already ended (its own time ran out) is no error.
+actionunban = <_curl> -X DELETE "<url>/api/v1/banlists/<list>/bans?address=<ip>"
+
+[Init]
+
+# The ban list, and Housecarl's URL (its listen address).
+list =
+url = https://127.0.0.1:8070
+# The API token, in a file only root reads.
+tokenfile = /etc/fail2ban/housecarl.token
+# More curl options: --cacert /etc/fail2ban/housecarl-ca.pem for a
+# private CA, --unix-socket for the local socket.
+curlopts =
+
+_curl = curl -sS --max-time 10 <curlopts> -o /dev/null -H "Authorization: Bearer $(cat <tokenfile>)"

docs/api.md

@@ -57,7 +57,9 @@ Calls that change the configuration answer:
   one). Missing when a person must confirm (`manual_confirm`).
 * `?dry_run=1` checks the change, with nftables too, and returns what it
   would do, with `"applied": false, "dry_run": true`, and `diff`: the
-  ruleset's unified diff.
+  ruleset's unified diff, each `@@` line followed by the chain (or other
+  block of the table) the hunk starts in, as in `@@ -40,6 +40,8 @@ chain
+  forward`.
 * `?changeset=ID` (or the header `X-Housecarl-Changeset: ID`) stages the
   change in that changeset instead ([Changesets](#changesets)): the answer
   has `"staged": true`, `changes` (this operation's) and `changeset`.
@@ -108,15 +110,15 @@ Lists replace the old ones. `probation_seconds` 0 is the default (120).
 
 ### Objects
 
-Zones, sets, services, rules, port forwards, source NAT and redirects
+Zones, sets, services, rules, port forwards, source NAT, redirects and
-share one pattern, `/{kind}` with kind `zones`, `sets`, `services`,
+ban lists share one pattern, `/{kind}` with kind `zones`, `sets`,
-`rules`, `forwards`, `snats` or `redirects`:
+`services`, `rules`, `forwards`, `snats`, `redirects` or `banlists`:
 
 | | |
 |---|---|
 | `GET /{kind}` | all of them, in order; `GET /rules?chain=input` for one chain; `GET /services` includes the built-in ones |
 | `POST /{kind}[?before=ID\|after=ID\|first=1]` | create; rules, forwards and NAT rules go last unless given a `position`, or placed before or after another of their chain, or first, in the same change (one history entry; staged in a changeset, the place goes with it) |
-| `GET /{kind}/{ref}` | by ID, or name for zones, sets, services and forwards |
+| `GET /{kind}/{ref}` | by ID, or name for zones, sets, services, forwards and ban lists |
 | `PATCH /{kind}/{ref}` | change the fields given (a JSON merge: `null` clears) |
 | `DELETE /{kind}/{ref}` | refused while something uses it |
 | `POST /rules/{ref}/reset-quota` | start a rule's quota again now (`config:write`; audited, not staged). Optional body: `{"address": "192.168.1.23"}` starts only that address's again (a per-address quota; an IPv6 address counts for its /64; 404 if it hasn't used the quota); `{"give": 5368709120}` takes that many bytes off what was used instead (the address's, or every address's), until the next reset |
@@ -127,6 +129,7 @@ The objects:
 ```json
 {"name": "lan", "interfaces": ["eth1", "eth1.*"], "external": false, "comment": ""}
 {"name": "trusted", "entries": ["192.168.1.0/24", "2001:db8:1::/64"], "dynamic": false, "timeout": 0, "comment": ""}
+{"name": "nas", "entries": [], "jarl": {"names": [{"name": "nas.example.com", "view": "internal"}], "within": ["lan", "10.9.0.0/16"]}, "comment": ""}
 {"name": "web", "entries": ["tcp/8080", "tcp/8443"], "comment": ""}
 {"chain": "input",
  "in_zones": ["wan"], "not_in": false, "out_zones": [], "not_out": false,
@@ -143,9 +146,26 @@ The objects:
  "comment": "", "disabled": false}
 ```
 
+A set with `jarl` takes its addresses from Jarl ([jarl.md](jarl.md#sets-from-jarl)):
+`names` are names in Jarl, each with a `view` (left out: the only view that
+has it); `within` are zones and addresses its addresses must lie in. It
+has no `entries` and isn't `dynamic`; `"jarl": null` makes it an ordinary
+set again.
+
 A source NAT rule is a match (as a rule's, without the rule's other
 fields) with `"to"` (empty: masquerade), a redirect a match with
-`"to_port"`. Times are seconds (`timeout`).
+`"to_port"`. A ban list ([bans.md](bans.md)):
+
+```json
+{"name": "web", "scope": "hosts", "hosts": ["10.0.10.57"], "never": ["trusted"],
+ "default_time": 3600, "max_time": 604800, "max_entries": 10000, "group_v6": 64, "comment": "", "disabled": false}
+```
+
+`scope` is `firewall`, `hosts` or `everything`; 0 is the default for the
+numbers, and `max_time` -1 is no limit. A ban list can't be renamed.
+Someone with a `bans` grant but no `config:read` may read the ban lists
+the grant covers (`GET /banlists`, `GET /banlists/{ref}`). Times are
+seconds (`timeout`).
 
 ### Statistics
 
@@ -196,6 +216,51 @@ These need `sets:read` or `sets:write`, for that set
 ([permissions.md](permissions.md)); they aren't on probation or in the
 history, but are audited.
 
+### Sets from Jarl
+
+| | |
+|---|---|
+| `GET /sets/{name}/jarl` | what the set holds and why (below) |
+| `POST /sets/{name}/jarl/refresh` | reads Jarl now (for every set from Jarl), then answers as `GET` |
+
+They need `sets:read` for that set. 400 for a set that doesn't come from
+Jarl. The answer:
+
+```json
+{"set": "nas", "configured": true, "read": "2026-10-23T14:02:11Z", "error": "",
+ "entries": ["10.10.0.20", "10.10.0.21"], "within": ["lan"],
+ "names": [{"name": "files.example.com", "view": "", "found_view": "internal", "chain": ["nas.example.com"],
+            "addresses": [{"address": "10.10.0.20", "used": true},
+                          {"address": "2001:db8:10::20", "used": false, "why": "not within lan"}],
+            "problem": "", "checked": "2026-10-23T14:02:11Z", "error": ""}]}
+```
+
+* `configured`: `housecarl.yaml` names a Jarl server; `read`: when Jarl's
+  zones were last read; `error`: why the last read failed (the set keeps
+  its addresses).
+* `entries`: the addresses the set holds now.
+* For each name: `found_view` is the view it was read from, `chain` the
+  CNAMEs followed, `addresses` every address Jarl gives it with `used`
+  (or `why` not), `problem` why it gives none, `checked` when Jarl last
+  answered for it, and `error` why the last try failed (its addresses are
+  then those of `checked`).
+
+### Bans
+
+| | |
+|---|---|
+| `GET /bans` | the active bans of every ban list you may read: `id`, `list_id`, `list`, `address` (an address, or an IPv6 prefix), `protocol` and `port` (none: every port), `expires` and `timeout` (seconds left; none: no end), `created`, `who`, `source`, `reason` |
+| `GET /banlists/{ref}/bans` | one list's |
+| `POST /banlists/{ref}/bans` | ban: `{"address": "203.0.113.9", "protocol": "tcp", "ports": "ssh", "time": 3600, "source": "guard/ssh", "reason": "…"}`. `ports` is a number, a string (`"22"`, `"http,https"`, `"0:65535"` or `"all"` for every port) or a list; without a protocol a number is TCP and UDP, a service its own protocols. `time` 0 is the list's default, -1 its longest; longer is cut down. 201 with `{"bans": [ban…, "existing": true for a renewed one], "closed": N}` (connections closed) |
+| `DELETE /banlists/{ref}/bans/{id}` | lift one ban |
+| `DELETE /banlists/{ref}/bans?address=A` | lift all of an address's bans (404 if it has none) |
+
+These need `bans:read` or `bans:write` for the list
+([permissions.md](permissions.md)); bans aren't on probation or in the
+history, but are audited (`ban.add`, `ban.remove`). Refusals: `422
+never_ban` (inside, the firewall's own, the caller's own, or in the
+list's `never`), `422 list_full`, `409` for a disabled list.
+
 ### Probation
 
 | | |
@@ -210,6 +275,7 @@ history, but are audited.
 |---|---|
 | `GET /history[?limit=&before=]` | changes, newest first |
 | `GET /history/{id}` | one, with each object before and after |
+| `GET /history/{id}/diff` | `{"diff"}`: what it did to the ruleset, as a unified diff with each hunk's chain (the configuration before and after it, got back from the current one, rendered by this version) |
 | `POST /history/{id}/revert` | undo it; 409 if an object it touched has changed since, or it was undone already |
 | `POST /import/nft` | `{"json": NFT_JSON, "text": "nft -a list ruleset output", "defines": "ruleset file", "table": "inet main", "zones": {"enp2s0": "lan"}, "replace": false}` ([import.md](import.md)); answers with `state` (the imported configuration), `notes` and `raw` too |
 | `POST /takeover` | `{"tables": ["inet main"]}`: delete these tables (administrators); on probation over the network; 409 in shadow mode |

docs/bans.md

@@ -0,0 +1,148 @@
+# Ban lists
+
+A **ban list** is where a program bans addresses: Guard (Housecarl's
+companion, which reads logs), fail2ban with Housecarl's action, or you
+with `hc ban`. The program says only *which address*, and perhaps a
+protocol and ports. The ban list says what that address is kept from.
+So a web server that sees password guessing in its own logs can ban the
+guesser at the router without knowing anything about the router.
+
+## Ban lists
+
+```sh
+hc banlist add router --scope firewall                   # the firewall itself
+hc banlist add web --scope hosts --host 10.0.10.57 --host 2001:db8:10::57
+hc banlist add edge --scope everything --never trusted
+```
+
+| Scope | Banned addresses are kept from | Where the drops are |
+|---|---|---|
+| `firewall` | the firewall itself: its SSH, DNS, web UI | `input` |
+| `hosts` | the list's hosts (addresses or sets), behind the firewall | `forward`, to those addresses |
+| `everything` | the firewall and everything behind it | `input` and `forward` |
+
+A `hosts` list covers port forwards to its hosts as well: the forward
+chain sees a forwarded connection's translated address and port, the
+host's own. A web server's Guard bans `tcp/22`, and that is right even
+when the router forwards its port 2222 to it.
+
+Other settings, with their defaults:
+
+| Setting | Default | |
+|---|---|---|
+| `never` | none | addresses, prefixes or sets this list never bans |
+| `default_time` (`--time`) | 1h | a ban's length when the program asks for none |
+| `max_time` (`--max-time`) | 7d | the longest ban; longer ones are cut to it. `-1` (`none`): no limit, so bans may be permanent |
+| `max_entries` | 10000 | the most bans the list holds; more are refused (`list_full`) |
+| `group_v6` | 64 | the IPv6 prefix length banned for an address. One customer usually has a whole /64 and can move around in it; 128 bans the one address. IPv4 addresses are banned alone |
+| `disabled` | no | the list's bans aren't in force (they are kept) |
+
+A ban list can't be renamed: the tokens and programs that ban into it
+know it by its name. Make a new one instead.
+
+## Bans
+
+```sh
+hc ban edge 203.0.113.9 --time 1d --reason "port scan"
+hc ban web 203.0.113.9 --tcp ssh --tcp 8443
+hc bans                       # every list's
+hc bans web
+hc unban web 203.0.113.9      # all of the address's bans in web
+hc unban web 17               # one, by ID
+```
+
+A ban is of **every port**, or of **a protocol's ports** (numbers or
+service names, built-in or yours). A port without a protocol is banned
+for TCP and UDP; a service name takes the service's protocols. Banning an
+address again renews the ban: its new time counts from now.
+
+Bans are dropped **ahead of every rule** in their chains, and ahead of
+the built-in that lets established connections through, so a ban cuts a
+connection that is already open. Housecarl also closes the banned
+address's tracked connections the ban covers when it bans it, because
+connections offloaded to the flowtable no longer pass the rules at all.
+Replies to connections the inside opened to a banned address are
+dropped too.
+
+Bans are kept in the database, apart from the configuration (like a
+dynamic set's entries): they aren't in the history, can't be undone,
+aren't on probation, and don't go through changesets. They end by
+themselves; every change, restart and reboot puts the active ones back
+with the time they have left. Each ban and unban is in the audit log
+(`ban.add`, `ban.remove`), with the program's source and reason.
+
+### What is never banned
+
+Whatever a list's `never` says, Housecarl refuses (`422 never_ban`) to
+ban:
+
+* the inside: addresses in networks of inside zones' interfaces, and
+  private addresses outside the external zones' networks;
+* the firewall's own addresses, and its own prefixes (settings);
+* the address of whoever asks (a program can't lock itself out);
+* loopback, link-local, multicast and unspecified addresses.
+
+A ban grouped to a prefix (IPv6) is refused when the prefix overlaps any
+of these.
+
+## Programs and tokens
+
+Give each program a token for its list alone. A `bans` grant can name
+ban lists, as a `sets` grant names sets:
+
+```sh
+hc user add guard-web --no-password --grant bans:write:web
+hc token create web --user guard-web          # as root on the firewall
+```
+
+With it, the program may ban into `web` and lift its bans, list them,
+and read the list itself (`GET /banlists/web`: its grouping and times),
+and nothing else. `viewer` has `bans:read`, `operator` `bans:write`.
+
+## Guard
+
+Guard reads log files and the systemd journal on any machine, and bans
+the addresses that misbehave into a ban list (its own documentation).
+Run it on the web server with a token for `web`, and on the router with
+one for `router` (or the local socket).
+
+## fail2ban
+
+Housecarl ships an action for fail2ban,
+`/usr/share/doc/housecarl/contrib/fail2ban/action.d/housecarl.conf`
+(`contrib/` in the source). Copy it to `/etc/fail2ban/action.d/`, put
+the token in `/etc/fail2ban/housecarl.token` (mode 0600), and use it in a
+jail:
+
+```ini
+[sshd]
+enabled = true
+action  = housecarl[list=web, url="https://router.lan:8070"]
+```
+
+The jail's `port` and `protocol` go with each ban: `port = ssh` bans only
+`tcp/22`, fail2ban's default `0:65535` bans every port. A `bantime` of
+`-1` is the list's longest ban. When fail2ban unbans an address Housecarl
+already let go (its own time ran out first), nothing happens. Add
+`curlopts = --cacert /etc/fail2ban/housecarl-ca.pem` for a private CA.
+
+## Shadow mode
+
+In shadow mode the ban rules count what they would drop
+(`[would drop]`) and let it through, like every other rule, and banning
+closes no connections.
+
+## The ruleset
+
+Each list has four sets, `ban_<id>_v4`, `ban_<id>_v6` (every port) and
+`ban_<id>_v4_svc`, `ban_<id>_v6_svc` (address, protocol and port), all
+with timeouts:
+
+```
+ip saddr @ban_3_v4 counter drop comment "hc:ban3"
+ip saddr . meta l4proto . th dport @ban_3_v4_svc counter drop comment "hc:ban3"
+ip6 saddr and ffff:ffff:ffff:ffff:: @ban_3_v6 counter drop comment "hc:ban3"
+```
+
+Set names starting with `ban_` are therefore Housecarl's own
+(`set_name_reserved`).

docs/cli.md

@@ -60,7 +60,8 @@ applied and saved (history 12; undo with 'hc history undo 12')
 ```
 
 `-n` shows what would change without changing it, with the diff of the
-ruleset; nftables checks it too.
+ruleset (each `@@` line names the chain the lines below it are in);
+nftables checks it too.
 
 ## Changesets
 
@@ -153,8 +154,10 @@ by name.
 | `zone delete ZONE` | refused while rules use it |
 | `set list`, `set show SET` | |
 | `set add NAME [ENTRY...] [--dynamic] [--timeout 24h] [--comment C]` | |
-| `set update SET [--entry E]... [--add E] [--remove E] [--timeout] [--name] [--comment]` | `--entry` replaces the entries |
+| `set add NAME --jarl NAME[@VIEW]... --within ZONE\|NETWORK...` | a set from Jarl: the names' addresses, only those within the zones and networks ([jarl.md](jarl.md#sets-from-jarl)) |
+| `set update SET [--entry E]... [--add E] [--remove E] [--timeout] [--jarl N]... [--within W]... [--name] [--comment]` | `--entry` replaces the entries, `--jarl` a Jarl set's names, `--within` where its addresses may be |
 | `set entries SET`, `set entries add SET ADDRESS [--timeout 1h]`, `set entries remove SET ADDRESS` | a dynamic set's entries |
+| `set jarl SET [--refresh]` | a set from Jarl: each name's addresses in Jarl (CNAMEs followed), used or why not, and when Jarl answered; `--refresh` reads Jarl first |
 | `set delete SET` | |
 | `service list`, `service show SERVICE` | with the built-in ones |
 | `service add NAME ENTRY... [--comment C]` | entries `tcp/22`, `udp/1000-2000`, `icmp/echo-request`, `icmpv6/packet-too-big` |
@@ -204,6 +207,19 @@ accept|drop|reject|log`, `--reject-with tcp-reset`, `--log`,
 
 See [nat.md](nat.md).
 
+### banlist, ban
+
+| Command | |
+|---|---|
+| `banlist list`, `banlist show BANLIST` | ban lists, with their bans' count |
+| `banlist add NAME --scope firewall\|hosts\|everything [--host ADDR\|SET]... [--never ADDR\|SET]... [--time 1h] [--max-time 7d\|none] [--max-entries N] [--group-v6 64] [--disabled] [--comment C]` | |
+| `banlist update BANLIST [flags]`, `banlist delete BANLIST` | `--host` and `--never` replace the lists; no renaming |
+| `bans [BANLIST]` | the active bans |
+| `ban BANLIST ADDRESS [--tcp PORT\|SERVICE]... [--udp …]... [--time 1h\|none] [--reason R]` | ban every port, or some; again renews |
+| `unban BANLIST ADDRESS\|ID` | lift one ban, or all of an address's |
+
+See [bans.md](bans.md).
+
 ### settings
 
 | Command | |
@@ -218,7 +234,8 @@ See [nat.md](nat.md).
 | `confirm` | keep the changes on probation; the ruleset is saved for the boot |
 | `rollback` | undo the changes on probation now |
 | `history list [--limit N]` | changes, newest first |
-| `history show ID` | each object before and after |
+| `history show ID` | each object before and after (a changed setting by its own fields: `builtins.drop_invalid: false -> true`) |
+| `history diff ID` | what the change did to the ruleset |
 | `history undo ID` | apply the change backwards (refused if something it touched has changed since) |
 | `import [FILE\|-] [--text FILE] [--defines FILE] [--table T] [--zone IFACE=NAME]... [--replace]` | [import.md](import.md) |
 | `takeover TABLE... [-y]` | delete tables Housecarl's ruleset replaces (administrators); not in shadow mode |

docs/configuration.md

@@ -13,7 +13,8 @@ reads the file when it starts.
 | `listen` | `["127.0.0.1:8070"]` | addresses of the web UI and API (`host:port`). Keep them on localhost or a management network, and write an input rule that lets you reach them |
 | `tls.cert_file`, `tls.key_file` | none | serve HTTPS with this certificate; housecarld rereads it when the file changes, or on `systemctl reload housecarl` |
 | `tls.acme.*` | off | get the certificate from Let's Encrypt, with Jarl publishing the challenge ([certificates.md](certificates.md#settings)) |
-| `jarl.server`, `jarl.token_file` (or `jarl.token`), `jarl.ca_cert`, `jarl.insecure` | none | the Jarl server for the certificate's challenge, and its token ([jarl.md](jarl.md)) |
+| `jarl.server`, `jarl.token_file` (or `jarl.token`), `jarl.ca_cert`, `jarl.insecure` | none | the Jarl server for the certificate's challenge and the sets from Jarl, and its token ([jarl.md](jarl.md)) |
+| `jarl.refresh` | `1m` | how often the sets from Jarl read their names (10s or more; [jarl.md](jarl.md#when-the-addresses-change)) |
 | `ruleset` | `/var/lib/housecarl/ruleset.nft` | the confirmed ruleset, which `housecarl-ruleset.service` loads at boot; its fallback is saved beside it as `ruleset-fallback.nft` ([operations.md](operations.md#if-the-ruleset-fails-to-load-at-boot)). Change both paths in the unit too |
 | `trusted_proxies` | `[]` | addresses or prefixes of reverse proxies whose `X-Forwarded-For` and `X-Forwarded-Proto` are believed |
 | `socket` | `/run/housecarl/housecarl.sock` | the local API socket; `""` turns it off |

docs/design.md

@@ -56,7 +56,10 @@ As in Jarl, a change can be made at once or staged in a **changeset**,
 to be reviewed and applied together with others:
 
 * Each change is an **operation** (create, update, delete or move an
-  object, or change the settings), kept as the API received it.
+  object, or change the settings), kept as the API received it. A move
+  staged right after a move of the same object takes its place: moving a
+  rule up three steps is one operation, and moving it back where it was
+  takes it out.
 * Staged in a changeset, an operation is checked as it is added: the
   changeset with it must still be valid, and nftables must accept the
   ruleset it makes. Nothing is applied.
@@ -94,7 +97,8 @@ table inet housecarl { ... }
 Two things survive the replacement: the **entries of dynamic sets**
 (read before, written back with their remaining timeouts, in the same
 script), and the **counters** (housecarld adds the old totals to the
-new, so hits don't reset with every change).
+new, so hits don't reset with every change). Sets from Jarl are written
+with the addresses last read from Jarl.
 
 Every rule carries a comment `hc:<mark>`, such as `hc:r12` for rule 12,
 `hc:f3` for port forward 3, `hc:b-established` for a built-in. Counters
@@ -199,8 +203,15 @@ Housecarl's replaces it ([import.md](import.md)).
   may only change that set (`sets:write:guests`). Addresses, not MAC
   addresses: matching by MAC only works on the guests' own network
   segment.
-* **Names instead of addresses**: Steward knows every reservation's
+* **Names instead of addresses**: a set can take its addresses from Jarl
-  address and Jarl every name, so rules could name a device or a subnet.
+  ([jarl.md](jarl.md#sets-from-jarl)). housecarld reads the names' A and
+  AAAA records through Jarl's API (CNAMEs followed, one view per name)
+  and keeps the addresses that lie within the zones and networks the set
+  allows; Jarl never calls Housecarl. What was last read is kept (in the
+  database too) while Jarl can't be reached. A change of the addresses
+  applies the ruleset again without a history entry, as dynamic sets'
+  entries aren't in it either. Names Steward makes from leases must not
+  be used: a client chooses its own hostname.
 * **The web UI's certificate** comes through Jarl, as Steward's does
   ([certificates.md](certificates.md)).
 

docs/development.md

@@ -20,12 +20,14 @@ internal/
   server/             the HTTP API and the web UI, authentication, the local socket, probation, the log ring
   api/, client/       JSON types and the Go client shared by server and CLI
   auth/               passwords (argon2id), tokens, sessions, grants and roles
-  certs/, jarl/       the web UI's certificate through Jarl (docs/certificates.md)
+  certs/, jarl/       the web UI's certificate through Jarl (docs/certificates.md); jarl/ is the Jarl API client
+  jarlsets/           sets from Jarl: reads the names, follows CNAMEs, keeps what was read, within (docs/jarl.md)
   config/             housecarld's YAML configuration
   version/            what a build reports
   web/static/         the web UI: plain ES modules, no build step, embedded with go:embed
 deploy/               systemd units, sysusers.d and tmpfiles.d files, Debian package scripts
 scripts/e2e.sh        end-to-end test with real traffic through a router container
+scripts/fakejarl/     the bit of Jarl's API sets from Jarl read, for the e2e test
 scripts/mkdeb.sh      the Debian packages (make deb)
 scripts/logo.py       the web UI's logo from artwork/logo.svg
 scripts/banner.py     the README's banner from the web UI's logo and wordmark
@@ -135,6 +137,14 @@ As for Jarl and Steward:
 3. Run `make test && make e2e`.
 4. Commit as "Release X", tag it `git tag -a vX -m "Housecarl X"`, and push.
 
+A fix to a release candidate may go out as a build of it rather than a
+new candidate: `0.2.0-rc.3+git<count>-<commit>`, where `<commit>` is the
+short ID of the last commit before "Release X" and `<count>` is `git
+rev-list --count` of it. The count orders the builds (apt compares it as a
+number; the ID alone would order them at random); each sorts after
+`0.2.0-rc.3` and before `0.2.0-rc.4`. Debian writes it
+`0.2.0~rc.3+git<count>~<commit>`.
+
 The tag starts `.gitea/workflows/release.yml`, which checks the tag
 against `VERSION` and the CHANGELOG, runs the tests, builds the tarballs,
 the CLI for each OS and the `.deb`s, and publishes them

docs/jarl.md

@@ -1,24 +1,44 @@
 # Connecting Housecarl to Jarl
 
 Housecarl uses [Jarl](https://gitea.adbraun.lol/adam/jarl), the BIND
-manager, for its DNS records. In this version that means one thing: the
+manager, for two things:
-DNS-01 challenge for the web UI's certificate ([certificates.md](certificates.md)).
+
-Naming hosts in rules by their DNS names may use the same connection later.
+* the DNS-01 challenge for the web UI's certificate
+  ([certificates.md](certificates.md)): Housecarl writes a TXT record;
+* **sets from Jarl** ([below](#sets-from-jarl)): sets whose addresses are
+  those of names in Jarl, such as `nas.adbraun.lol`, kept up to date.
+  Housecarl only reads.
 
 Housecarl talks to Jarl's REST API with an API token. Give it a **user of its
-own**, with **only the permission it needs**.
+own**, with **only the permission it needs**. Jarl never calls Housecarl.
 
 ## 1. A user for Housecarl, in Jarl
 
 On the Jarl server, make a user without a password. It can't log in to
-Jarl's web UI, only use its tokens. Grant it the challenge record of
+Jarl's web UI, only use its tokens.
-Housecarl's own name, and nothing else:
+
+For **sets from Jarl**, grant it reading the records of the zones and views
+your names are in:
+
+```sh
+jarl user create housecarl --no-password --comment "Housecarl on fw01" \
+    --grant "records:read zones=adbraun.lol views=internal"
+```
+
+Include every zone a name's CNAMEs lead to as well (`zones=adbraun.lol,wg.adbraun.lol`).
+Reading is all it needs: it can't change anything in Jarl.
+
+For the **certificate**, grant it the challenge record of Housecarl's own
+name, and nothing else:
 
 ```sh
 jarl user create housecarl --no-password --comment "Housecarl on fw01" \
     --grant "records:write zones=adbraun.lol names=_acme-challenge.fw.adbraun.lol types=TXT"
 ```
 
+For both, give both grants (`--grant` twice). `jarl user update housecarl
+--grant ... --grant ...` replaces a user's grants with the ones given.
+
 Use your zone for `adbraun.lol`, and the name Housecarl's web UI is reached
 by for `fw.adbraun.lol` (`tls.acme.domain`). The grant lets the token add
 and remove TXT records at exactly `_acme-challenge.fw.adbraun.lol`:
@@ -63,7 +83,9 @@ around more readily.
 You can give the token an expiry (`--expires 365d`). Rotate it in Jarl with
 `jarl token rotate ID --grace 1d`, then put the new secret in the file and
 restart housecarld within the grace period. Since the certificate is renewed
-every couple of months, nothing breaks while you do.
+every couple of months, nothing breaks while you do. Sets from Jarl keep
+their addresses while the token doesn't work (they warn, see
+[below](#when-jarl-cant-be-reached)), so they don't break either.
 
 ## 3. Housecarl's settings
 
@@ -74,6 +96,7 @@ jarl:
   server: https://dns.adbraun.lol:8053
   token_file: /etc/housecarl/jarl.token
   # ca_cert: /etc/housecarl/jarl-ca.pem   # if Jarl's certificate isn't from a public CA
+  # refresh: 1m                           # how often sets from Jarl read their names
 ```
 
 Then restart housecarld (`systemctl restart housecarl`). Housecarl needs to
@@ -83,3 +106,192 @@ address Housecarl can reach, ideally over HTTPS.
 `hc cert check` ([certificates.md](certificates.md#checking)) tests
 the connection, the token's permission, and that the record reaches the
 internet.
+
+## Sets from Jarl
+
+A set can take its addresses from Jarl instead of listing them: you name
+DNS names, and the set holds their addresses. Rules use it like any other
+set. When a record changes in Jarl, the set follows within a minute,
+without a change to Housecarl's configuration.
+
+```sh
+hc set add nas --jarl nas.adbraun.lol@internal --within lan
+hc rule add forward --in wg --to nas --service smb
+hc set jarl nas                       # what it holds, name by name
+```
+
+In the web UI: Sets → Add set, kind "from Jarl". The **Addresses…**
+button shows what the set holds.
+
+A set from Jarl has:
+
+* **names**: one or more names, each `NAME@VIEW`, or `NAME` when only one
+  of Jarl's views has it ([Views](#views));
+* **within**: where its addresses may be, one or more zones or networks
+  ([Within](#within)). It is required.
+
+It has no entries of its own, and isn't dynamic. It can be renamed (it goes
+by its names in Jarl, not by its own).
+
+### What a name gives
+
+Housecarl reads the name's records as named would answer them in the
+view:
+
+* **Every A and AAAA record** of the name. A name with three addresses
+  puts all three in the set, IPv4 and IPv6 alike; a rule using the set
+  matches each family with its own addresses.
+* **CNAMEs are followed**: `files.adbraun.lol CNAME nas.adbraun.lol.` gives
+  nas's addresses. Chains are followed up to 8 CNAMEs, from zone to zone
+  (a sub-zone such as `wg.adbraun.lol` too), but always in the **same
+  view**, and only into zones Jarl holds. `hc set jarl` shows the chain:
+  `files.adbraun.lol → nas.adbraun.lol`.
+* **Disabled records** are left out, as named leaves them out.
+
+A name gives **no addresses**, and a warning (`jarl_name`) says why, when:
+
+* it has no A, AAAA or CNAME record (only an MX, say, or nothing);
+* only a **wildcard** (`*.adbraun.lol`) would answer for it: wildcards
+  aren't followed, so name a record of its own;
+* a **CNAME leads out of Jarl** (`host.duckdns.org`), into a zone Jarl
+  doesn't hold, or to a name with no address;
+* the CNAMEs **loop**, or are more than 8;
+* it is **below a delegation**: NS records in the zone hand that part to
+  other servers, so Jarl doesn't hold its records;
+* its zone is a **secondary, mirror, stub or forward zone** (Jarl doesn't
+  hold their records), or **disabled** in Jarl;
+* no zone the token can see holds it.
+
+A **reverse zone** isn't involved: Housecarl reads the A and AAAA records
+only, never PTRs.
+
+An **in-view zone** (one view serving another's zone) is followed to the
+zone it serves: `srv.adbraun.lol@vps` reads the internal view's records if
+vps's `adbraun.lol` is an in-view of internal's.
+
+### Views
+
+The same name can have different addresses in different views: Jarl's
+`internal` view may give `nas.adbraun.lol` its private address, `external`
+a public one. A set reads **one view per name**, written `NAME@VIEW`:
+
+* **Name the view your devices see.** The firewall matches the addresses
+  packets carry, and for devices inside that is the internal view's.
+* **Without a view**, the name is read from the only view that has a zone
+  for it. If zones in **more than one view** hold it, the name gives
+  nothing until you name the view (`jarl_name`: "is in Jarl's views
+  external, internal: name the view"). This counts every view whose zones
+  cover the name, even one where the name has no record: a record added
+  there later would otherwise change which view Housecarl reads.
+* **Linked zones** make no difference: a shared record has the same
+  address in every view, and a view's own records are why the view is
+  named.
+* **Without views** in Jarl, write the name alone.
+* A set can mix views: `--jarl nas.adbraun.lol@internal --jarl
+  host.adbraun.lol@vps`.
+
+A wrong view can't widen the set: an address from it that isn't
+[within](#within) is left out.
+
+### Within
+
+`--within` says where the set's addresses may be. Each entry is:
+
+* **a zone**: the networks connected to its interfaces (the addresses on
+  them, as `hc status` lists them), IPv4 and IPv6;
+* **a network, address or range**: `10.10.0.0/24`, `2001:db8:10::/64`,
+  `192.0.2.7`.
+
+An address from Jarl that isn't within any of them is **left out** of the
+set, and a warning names it (`jarl_outside`: "nas.adbraun.lol has address
+192.0.2.9, which is left out: not within lan"). The set's other addresses
+stay. So a record changed in Jarl, by mistake or by someone who shouldn't,
+can only point the set at addresses you allowed.
+
+Zones grow by themselves: when you add a VLAN to the `lan` zone, or give
+an interface another network, its addresses count at once. A new zone
+counts only once you add it to `within`. If a zone's interfaces have no
+address for a while (at boot, a link down), the networks it had last count.
+
+Some addresses never count, whatever `within` says: unspecified (`0.0.0.0`,
+`::`), loopback and multicast ones.
+
+`within 0.0.0.0/0` or `::/0` lets any address in, and gives a warning
+(`set_jarl_anywhere`): then whoever can change the names in Jarl decides
+what the set holds. Name a zone or a network instead. For an address
+outside your networks, such as a VPS's public address, name that address
+or its network.
+
+### When the addresses change
+
+Housecarl reads the names every `jarl.refresh` (a minute), right after a
+change to Housecarl's configuration (a new set or name), when an interface
+changes, and when you ask: `hc set jarl NAME --refresh`, or **Read Jarl
+now** in the web UI.
+
+When a set's addresses change, housecarld puts the ruleset in force again
+with the new ones. That isn't a change of the configuration: there is no
+history entry and no probation. It is recorded in the audit log
+(`set.jarl`, "added 10.10.0.22; removed 10.10.0.20") and in the journal.
+
+A new set holds nothing for the moment until its names are read, usually
+less than a second.
+
+**Open connections aren't closed** when an address leaves a set, as with
+any change to a set: the connection's packets are let through as part of an
+established connection (or by the flowtable). Close them with `hc
+connections close` if they must stop at once.
+
+### When Jarl can't be reached
+
+A set **keeps the addresses it last had** while Jarl can't be read: Jarl is
+down, the network to it is, or the token stopped working. Nothing is
+emptied, so rules keep working. A warning says so (`jarl_unreachable`), on
+the status page and in `hc status`, and `hc set jarl` shows when Jarl last
+answered.
+
+What was last read is saved in the database. After a restart or a reboot,
+the sets get those addresses at once, before Jarl is read again, and the
+boot ruleset ([operations.md](operations.md)) has them too.
+
+When Jarl **answers** that a record is gone, its addresses go. Only a
+failure to read keeps them.
+
+Without `jarl.server` in `housecarl.yaml`, sets from Jarl keep what they
+had (nothing if Jarl was never read) and warn (`jarl_not_configured`).
+
+### Who decides what the set holds
+
+A set from Jarl lets **whoever can change those records in Jarl** decide
+which addresses a rule matches. Keep that in mind for rules that accept:
+
+* `within` limits it to networks you chose;
+* Housecarl's token only reads ([step 1](#1-a-user-for-housecarl-in-jarl));
+* give the records' zones only to people you'd let change the firewall,
+  and check Jarl's audit log for who changed what.
+
+**Don't use names that clients choose for themselves.** A name a DHCP
+server makes from the client's own hostname belongs to whoever asks for
+it: any guest could call itself `nas`. Name records that you made by hand,
+or that come from a DHCP reservation.
+
+### Seeing what a set holds
+
+```
+$ hc set jarl nas
+Set:        nas
+Within:     lan
+Holds:      10.10.0.20, 10.10.0.21
+Jarl read:  2026-10-23 14:02:11
+
+NAME                                 VIEW      ADDRESS          USED
+files.adbraun.lol → nas.adbraun.lol  internal  10.10.0.20       yes
+files.adbraun.lol → nas.adbraun.lol  internal  10.10.0.21       yes
+files.adbraun.lol → nas.adbraun.lol  internal  2001:db8:10::20  no: not within lan
+```
+
+The web UI's **Addresses…** button on the Sets page shows the same, and the
+status page lists the warnings: names that give nothing (`jarl_name`),
+addresses left out (`jarl_outside`), Jarl not read (`jarl_unreachable`).
+The API is `GET /sets/{name}/jarl` ([api.md](api.md#sets-from-jarl)).
+

docs/operations.md

@@ -83,7 +83,10 @@ sudo nft -c -f /var/lib/housecarl/ruleset.nft     # check it
 In shadow mode both files are shadow mode's, and the fallback filters
 nothing ([shadow.md](shadow.md#what-works-differently)).
 
-Dynamic sets start empty after a reboot. The saved ruleset has no
+Dynamic sets start empty after a reboot. Sets from Jarl have the
+addresses they last had, in the saved ruleset and again when housecarld
+starts, whether Jarl is reachable yet or not ([jarl.md](jarl.md#when-jarl-cant-be-reached)).
+The saved ruleset has no
 flowtable, since its devices may not exist yet: housecarld adds it when
 it starts, and whenever a flowtable device appears
 ([flowtable.md](flowtable.md#devices-that-come-and-go)).
@@ -164,9 +167,9 @@ start again. A disabled rule keeps its count for when it is enabled.
 resets; `hc rule reset-quota ID` starts one again (`--address` one device's,
 `--give 5gbytes` a top-up until the next reset). housecarld resets
 quotas at midnight when their period ends (late, if it was stopped then),
-and saves their usage every five minutes and when it stops; after a
+and saves their usage every five minutes, after every change and when
-reboot it puts it back. A reboot without a clean stop loses at most the
+it stops; after a reboot it puts it back. A reboot without a clean stop
-last five minutes' count.
+loses at most the last five minutes' count.
 
 ## The log
 
@@ -309,6 +312,22 @@ down, the fallback and a missing ruleset. Reach it from where the input
 rules let the monitor in (a rule for the Checkmk server's address and
 port 8070).
 
+## Failed logins in the journal
+
+A failed login to the web UI or the API, and a refused API token, are
+written to the journal as well as the audit log, with the address first:
+
+```
+level=WARN msg="login failed" ip=203.0.113.9 user=admin reason="wrong username or password"
+level=WARN msg="token refused" ip=203.0.113.9 reason="wrong token secret"
+```
+
+Guard's `housecarl` preset, or a fail2ban filter, can ban such addresses
+([bans.md](bans.md)). The address comes before the user name, which a
+caller chooses, so a pattern anchored on `msg="login failed" ip=` can't
+be fooled by a name. (With `log.format: json` they are JSON objects with
+the same fields, in the same order.)
+
 ## Checks
 
 `housecarld check` validates the configuration in the database against

docs/permissions.md

@@ -8,7 +8,8 @@ else gets **grants**, `resource:access`:
 | Resource | read | write |
 |---|---|---|
 | `config` | settings, zones, sets, services, rules, NAT, the ruleset, history, interfaces, probation, changesets (the web UI shows the forms locked) | change them, stage and apply changesets (your own, or anyone's for administrators), undo, import, confirm and roll back; close connections; start and stop traces |
-| `sets` | dynamic sets' entries | add and remove entries |
+| `sets` | dynamic sets' entries, what sets from Jarl hold | add and remove entries |
+| `bans` | ban lists' bans, and the lists the grant names | ban and unban ([bans.md](bans.md)) |
 | `log` | hit counters, the log, connections, traces | – |
 | `audit` | the audit log | – |
 | `*` | all of the above | |
@@ -20,6 +21,10 @@ program, such as Steward's captive portal, which should be able to let a
 client in and nothing more. A dynamic set's entries need a `sets` grant
 even for those with `config:write`.
 
+A `bans` grant names ban lists the same way: `bans:write:web` may ban
+into the list `web` (and read it) and nothing else, the grant for Guard
+or fail2ban on the web server.
+
 Only administrators may delete other tables (`hc takeover`), and manage
 users and the certificate (`hc cert`, Server → Certificate).
 
@@ -27,8 +32,8 @@ users and the certificate (`hc cert`, Server → Certificate).
 
 | Role | Grants |
 |---|---|
-| `viewer` | `config:read sets:read log:read` |
+| `viewer` | `config:read sets:read bans:read log:read` |
-| `operator` | `config:write sets:write log:read audit:read` |
+| `operator` | `config:write sets:write bans:write log:read audit:read` |
 | `log` | `log:read`, e.g. for a monitoring script |
 
 ```sh
@@ -49,9 +54,13 @@ hc token create portal --user portal --grant sets:write:guests --expires 365d
 ```
 
 The secret is shown once; only its hash is stored. A restricted token can
-only create tokens with a subset of its own grants. The web UI only offers
+only create tokens with a subset of its own grants.
-roles within what your account may do; a token with more would get no
+
-more than its user anyway.
+In the web UI, Account → New token makes one of your own; an
+administrator makes one for another user with New token on that user's
+row under Users (`--user` in the CLI, `POST /users/{id}/tokens` in the
+API). The dialog only offers roles within what the token's user may do; a
+token with more would get no more than its user anyway.
 
 **Rotating** gives a token a new secret, keeping its ID, name and
 permissions, so only the programs that use it need updating:
@@ -82,6 +91,6 @@ on probation like any other.
 
 Logins (and failed ones), users, tokens, every configuration change (with
 its history entry), changesets created, applied and discarded,
-confirmations and rollbacks, imports, takeovers and
+confirmations and rollbacks, imports, takeovers,
-dynamic set entries are recorded with who, from where and how: `session`,
+dynamic set entries and bans are recorded with who, from where and how: `session`,
 `token` or `socket`.

docs/rules.md

@@ -83,6 +83,19 @@ change to the ruleset, and a restart of housecarld; a reboot empties
 them. A token can be limited to one set ([permissions.md](permissions.md)):
 that is how another program (Steward's captive portal) lets a client in.
 
+A set **from Jarl** holds the addresses of names in Jarl, the BIND
+manager: every A and AAAA record of each name, CNAMEs followed, read again
+every minute. Only addresses within the zones and networks it names are
+used, so a changed record can't open the firewall to anything else:
+
+```sh
+hc set add nas --jarl nas.example.com@internal --within lan
+hc set jarl nas                                      # what it holds, and why
+```
+
+Views, CNAMEs, what happens when Jarl can't be reached and the rest are in
+[jarl.md](jarl.md#sets-from-jarl).
+
 ## Services
 
 A service names ports of a protocol (`tcp`, `udp`, `sctp`) and ICMP
@@ -117,6 +130,11 @@ drops or rejects decides. What no rule decides gets the chain's
 **policy** (Settings): by default input and forward drop, output
 accepts.
 
+On the Rules page, ↑ and ↓ move a rule one place; **Move…** puts it
+before any other rule of its chain, or at the end, in one change
+(`hc rule move ID --before ID`). In a changeset, moves of the same rule
+one after another are kept as one operation.
+
 ```sh
 hc rule add input --from trusted --service ssh --comment "SSH from home"
 hc rule add input --in wg --service dns
@@ -165,6 +183,40 @@ hc rule add forward --in wan --status dnat
 hc rule add forward --in wan -a drop
 ```
 
+### Matching everything but a few
+
+A field matches **any of** its entries, or with `--not-…` ("any but" in
+the web UI) anything else; it can't do both. "The LAN except the NAS" is
+still one rule: the zone says which network, and the addresses say which
+of it to leave out, because zones and addresses are different fields and
+a rule needs all of them to match.
+
+| What you want | One rule |
+|---|---|
+| the LAN, except the NAS | `--in lan --from nas --not-from` |
+| everyone on guest, except one device, has a quota | `--in guest --from tv --not-from --quota 10gbytes,over,daily` |
+| the internet, except one host | `--out wan --to blocked --not-to` |
+
+```sh
+# Each device on the LAN: 50 GB a month, but not the NAS (its backups)
+hc rule add forward --in lan --out wan --from nas --not-from --quota 50gbytes,over,per-source,monthly -a drop
+```
+
+Leaving part of an address range out ("10.0.0.0/8 except 10.0.5.0/24")
+when it isn't a zone takes one of:
+
+* **Two rules, the exception first**, when the exception gets the
+  opposite action: `--from 10.0.5.0/24 -a drop` above `--from
+  10.0.0.0/8`. There is no action that skips a rule and goes on, so this
+  doesn't work when the exception should just fall through to later
+  rules.
+* **Ranges around the hole**: `--from 10.0.0.0-10.0.4.255 --from
+  10.0.6.0-10.255.255.255`.
+* **A [raw rule](#raw-rules)**: `ip saddr 10.0.0.0/8 ip saddr != 10.0.5.0/24 accept`.
+
+There's no need to leave a zone out of other zones: an interface belongs
+to one zone, so "any of lan, guest" already leaves out everything else.
+
 ### Bandwidth and quotas
 
 A **byte rate** limits bandwidth: `--limit 20mbytes/second,over,per-source
@@ -209,12 +261,26 @@ Statistics**.
 
 nftables counts a quota but never resets it, and forgets it when its
 table is replaced: Housecarl carries what each quota used across every
-change and restart, saves it every five minutes (and when housecarld
+change and restart, saves it every five minutes (and after each change,
-stops) for after a reboot, and resets quotas when their period ends.
+and when housecarld stops) for after a reboot, and resets quotas when their period ends.
 A per-address quota counts an address: a device that gets a new one
 starts again. With Steward's reservations IPv4 addresses stay; IPv6 is
 grouped by /64 (below).
 
+Changing the amount, `over` or the resets keeps what was used. Changing
+how the quota counts carries what can be carried:
+
+| Change | What was used |
+|---|---|
+| per address to one total | the addresses' sum |
+| to wider groups (IPv6 /64 to /56) | added up per new group |
+| a total to per address | starts again: a total can't be split |
+| per source to per destination (or back) | starts again |
+| to finer groups (/64 to /128) | starts again: a group can't be split |
+
+A change that starts a quota again says so (warning `quota_restarts`),
+when it is staged for review and in `hc` (also with `-n`).
+
 **Rules with a quota or a byte rate count every packet.** The built-in
 that accepts established connections comes before your rules, so a rule
 there only sees each connection's first packet. Rules that count traffic
@@ -254,6 +320,13 @@ In shadow mode ([shadow.md](shadow.md)) a raw rule's final `drop` or
 (NAT, `meta mark set`, `jump`, `notrack`, a verdict map…) is left out,
 with a warning (`shadow_raw_left_out`).
 
+## Ban lists
+
+Programs such as Guard and fail2ban ban addresses into ban lists, and
+those bans come first of all in the input and forward chains (after
+loopback in input), before the built-ins and every rule. See
+[bans.md](bans.md).
+
 ## Built-ins
 
 Housecarl adds the rules every firewall needs before yours. Each can be
@@ -274,7 +347,12 @@ UI), and `hc ruleset` shows them:
 **Your prefixes** (`--own-prefix 2001:db8::/48`) are your delegated
 IPv6 prefix and public addresses: nothing from outside should come from
 them. The antispoof lists can be changed with `--antispoof-v4` and
-`--antispoof-v6`.
+`--antispoof-v6`. Link-local addresses (`fe80::/10`) are refused in the
+IPv6 list and in your prefixes (`antispoof_link_local`): your ISP's
+router sends its router adverts and DHCPv6 replies from them, and
+antispoofing runs in the early chain, before the ICMPv6 and DHCPv6
+client built-ins could accept them, so the router would lose its IPv6
+default route and, later, its delegated prefix.
 
 The **flowtable** (`--flowtable wan --flowtable eth1`) lets established
 TCP and UDP connections forwarded between those devices skip the rules,

docs/shadow.md

@@ -116,6 +116,9 @@ firewall's NAT still does the work.
 * **No takeover, no closing connections.** `hc takeover` (deleting your
   firewall's tables) and `hc connections close` are refused (409,
   `hc` exits with 5): both would change your traffic.
+* **Bans** ([bans.md](bans.md)) are kept and their rules count what they
+  would drop (`[would drop]`), but nothing is dropped, and banning closes
+  no connections.
 * **The boot.** `housecarl-ruleset.service` loads the shadow ruleset at
   boot. Its fallback ([operations.md](operations.md#if-the-ruleset-fails-to-load-at-boot))
   is an empty table that filters nothing, since your firewall protects the

docs/stats.md

@@ -5,7 +5,9 @@ Housecarl keeps what the firewall did over time:
 - traffic per interface and zone, received and sent;
 - packets dropped, by chain, and when drops happen (a weekday × hour
   heatmap);
-- hits per rule, built-in and policy, and the rules that matched nothing;
+- hits per rule, and per built-in and policy in a list of their own (the
+  established built-in counts most packets), and the rules that matched
+  nothing;
 - the sources blocked most and what they tried (from the log);
 - traffic per inside device (a setting, below);
 - connections tracked, against the kernel's limit;
@@ -127,7 +129,7 @@ answer.
 | Endpoint | |
 |---|---|
 | `GET /stats/status` | `enabled`, `database`, `size`, `first_data`, `last_sample`, `sample_error`, `per_device`, `retention`, `latest` (the newest gauges) |
-| `GET /stats/summary?since=24h&limit=10` | `zones` and `interfaces` (`name`, `received`, `sent`), `drops`, `drops_by_chain`, `rules` (busiest, named), `peak_connections`, `conntrack_max`, `blocked_sources`, `blocked_ports`, `devices_up`, `devices_down` |
+| `GET /stats/summary?since=24h&limit=10` | `zones` and `interfaces` (`name`, `received`, `sent`), `drops`, `drops_by_chain`, `rules` (busiest rules and NAT objects, named), `builtins` (busiest built-ins and policies, named), `peak_connections`, `conntrack_max`, `blocked_sources`, `blocked_ports`, `devices_up`, `devices_down` |
 | `GET /stats/timeline?keys=zrx:*,drops&since=24h&step=auto` | `step`, `times` (bucket starts), `series` (`key`, `values`); `GROUP:*` means every key of a group; `step` is `auto`, `1m`, `5m`, `15m`, `1h`, `6h` or `1d`; a gauge without a sample is -1 |
 | `GET /stats/top?kind=device_down&since=7d&limit=20` | a top list (`key`, `count`) |
 | `GET /stats/hits?since=30d` | packets per rule, built-in and policy (`key`, `count`, `name`), with the enabled rules that counted none |

docs/validation.md

@@ -31,6 +31,7 @@ are unique per kind, ignoring case.
 |---|---|---|
 | `policy` | error | a policy that isn't `accept` or `drop` |
 | `settings_address` | error | an own prefix or antispoof entry that isn't an address or prefix, or is in the wrong list (an IPv6 prefix in the IPv4 list) |
+| `antispoof_link_local` | error | an own prefix or IPv6 antispoof entry holds link-local addresses (`fe80::/10`): the ISP's router adverts and DHCPv6 replies come from them, so dropping them on external zones loses the IPv6 default route and, later, the delegated prefix. A configuration saved before this check keeps being applied; the next change is refused until the entry is taken out |
 | `flowtable_device` | error | a flowtable device with a wildcard: name each device |
 | `flowtable_device_missing` | warning, *host* | a flowtable device doesn't exist; the flowtable is left out until it does |
 | `probation_range` | error | the probation isn't 10 to 3600 seconds |
@@ -51,11 +52,16 @@ are unique per kind, ignoring case.
 
 | Code | | When |
 |---|---|---|
-| `set_name_reserved` | error | a set name starting with `meter_`, `conn_`, `quota_` or `stats_`: Housecarl's own sets (rate limits, quotas, statistics) use those |
+| `set_name_reserved` | error | a set name starting with `meter_`, `conn_`, `quota_`, `stats_` or `ban_`: Housecarl's own sets (rate limits, quotas, statistics, ban lists) use those |
 | `set_entry` | error | an entry that isn't an address, prefix (without host bits) or range |
-| `set_empty` | warning | a set (not dynamic) with no entries: rules using it match nothing |
+| `set_empty` | warning | a set (not dynamic, not from Jarl) with no entries: rules using it match nothing |
 | `set_dynamic_entries` | error | configured entries on a dynamic set: its entries come at run time |
 | `set_timeout` | error | a timeout on a set that isn't dynamic, or under a second |
+| `set_jarl_entries` | error | configured entries on a set from Jarl: its addresses are its names' ([jarl.md](jarl.md#sets-from-jarl)) |
+| `set_jarl_dynamic` | error | a set both dynamic and from Jarl |
+| `set_jarl_names` | error | a set from Jarl without names, with one that isn't a DNS name (a wildcard, say) or a bad view, or with a name twice |
+| `set_jarl_within` | error | a set from Jarl without `within`, or with an entry there that is neither a zone nor an address, network or range |
+| `set_jarl_anywhere` | warning | a set from Jarl `within 0.0.0.0/0` or `::/0`: any address may come in, so whoever changes the names in Jarl decides what it holds |
 | `service_empty` | error | a service with no entries |
 | `service_entry` | error | an entry that isn't `PROTO/PORTS` (`tcp`, `udp`, `sctp`; a port or range) or `icmp/TYPE`, `icmpv6/TYPE` with a type nftables knows |
 
@@ -97,6 +103,7 @@ These apply to rules, source NAT and redirects.
 | `rule_group` | error | a grouping prefix outside 1-32 (IPv4) or 1-128 (IPv6) |
 | `rule_traffic_accept` | error | a rule with a quota or a byte rate that accepts: it is checked before established connections are accepted, so it can only drop, reject or log |
 | `rule_every_packet_accept` | error | a rule checked against every packet (`every_packet`) that accepts: it comes before established connections are accepted, so it can only drop, reject or log |
+| `quota_restarts` | warning | a change makes a rule count its quota so that what it used can't carry over (a total to per address, per source to per destination, finer groups): it starts again. Only on the change that does it |
 | `flowtable_traffic` | warning | a forward rule checked against every packet (a quota, a byte rate, `every_packet`) while the flowtable is on: it only sees each connection's first packets |
 | `reject_with` | error | `tcp-reset` on a rule that matches more than TCP, or with an action other than reject |
 | `log_prefix` | error | a log prefix over 100 characters |
@@ -133,7 +140,25 @@ configuration: the dashboard and `hc status` show them.
 | `conntrack_full` | warning, *host* | the connection tracking table is over 80% full; once it is full, the kernel drops new connections. Raise `net.netfilter.nf_conntrack_max`, or find what opens so many ([stats.md](stats.md#warnings)) |
 | `takeover_pending` | warning, *host* | the table you imported from is still in force beside Housecarl's, so a packet must get past both; `hc takeover TABLE` deletes it once Housecarl's rules are right |
 | `shadow_unprotected` | warning, *host* | shadow mode, and no other table has a filter chain on the input hook: Housecarl's ruleset blocks nothing, and nothing else protects the machine. Load your firewall, or leave shadow mode ([shadow.md](shadow.md)) |
+| `jarl_name` | warning, *host* | a set from Jarl has a name that gives no addresses, and why: no A, AAAA or CNAME record, a wildcard only, a CNAME out of Jarl's zones or in a loop, below a delegation, a zone Jarl doesn't hold the records of, or in more than one view without one named ([jarl.md](jarl.md#what-a-name-gives)) |
+| `jarl_outside` | warning, *host* | an address a name has in Jarl is left out of its set: it isn't within the set's zones and networks ([jarl.md](jarl.md#within)) |
+| `jarl_unreachable` | warning, *host* | reading Jarl failed (unreachable, the token refused…), for every name or one; the sets keep the addresses they had ([jarl.md](jarl.md#when-jarl-cant-be-reached)) |
+| `jarl_not_configured` | warning, *host* | sets from Jarl, but no `jarl.server` in `housecarl.yaml`: they keep the addresses they last had |
 | `shadow_raw_left_out` | warning, *host* | shadow mode leaves this raw rule out: it does more to packets than accept, drop or reject (NAT, setting a mark or field, a jump, a verdict map…). Its hits aren't counted, and the rules after it see what it would have taken ([shadow.md](shadow.md#what-changes-in-the-ruleset)) |
 
 In shadow mode `nftables_service` and `takeover_pending` aren't raised:
 another firewall beside Housecarl is the point there.
+
+## Ban lists
+
+| Code | | When |
+|---|---|---|
+| `banlist_name` | error | not a valid name (as for zones and sets) |
+| `banlist_name_taken` | error | two ban lists with one name |
+| `banlist_scope` | error | a scope other than `firewall`, `hosts` or `everything` |
+| `banlist_hosts` | error | scope `hosts` without hosts, or hosts with another scope |
+| `banlist_address` | error | a host or never entry that isn't an address, prefix or range |
+| `unknown_set` | error | a host or never entry naming a set that doesn't exist |
+| `banlist_time` | error | negative times (but `max_time` -1), or a default longer than the longest |
+| `banlist_entries` | error | `max_entries` below 0 or above 1000000 |
+| `banlist_group` | error | `group_v6` outside 16 to 128 |

internal/api/types.go

@@ -532,3 +532,75 @@ type MatrixException struct {
 	// Marks are the counters behind Hits ("r12", "b-ping", "f3").
 	Marks []string `json:"-"`
 }
+
+// BanInput asks a ban list to ban an address (POST
+// /banlists/{list}/bans).
+type BanInput struct {
+	Address string `json:"address"`
+	// Protocol (tcp, udp) and Ports limit the ban; with neither, every
+	// port. Ports are numbers or service names, in a list or a string
+	// ("22", "ssh", "http,https"); "all", "0:65535" or "1-65535" mean
+	// every port. Ports without a protocol take the service's protocols,
+	// or for a number tcp and udp.
+	Protocol string          `json:"protocol,omitempty"`
+	Ports    json.RawMessage `json:"ports,omitempty"`
+	// Time is the ban's length in seconds: 0 the list's default, -1 its
+	// longest (or for ever). Longer than the list allows is cut down.
+	Time   int    `json:"time,omitempty"`
+	Source string `json:"source,omitempty"`
+	Reason string `json:"reason,omitempty"`
+}
+
+// BanResult is the answer to a ban: the bans made or renewed (one per
+// protocol and port), Existing for each already in force.
+type BanResult struct {
+	Bans []BanMade `json:"bans"`
+	// Closed counts the banned address's connections closed.
+	Closed int `json:"closed"`
+}
+
+// BanMade is a ban made, or renewed (Existing).
+type BanMade struct {
+	model.Ban
+	Existing bool `json:"existing,omitempty"`
+}
+
+// JarlSet is what a Jarl set holds and why (GET /sets/{ref}/jarl).
+type JarlSet struct {
+	Set string `json:"set"`
+	// Configured is whether housecarl.yaml names a Jarl server.
+	Configured bool `json:"configured"`
+	// Read is when housecarld last read Jarl's zones; Error why the last
+	// try failed (the set keeps the addresses it had).
+	Read  *time.Time `json:"read,omitempty"`
+	Error string     `json:"error,omitempty"`
+	// Entries are the addresses the set holds now.
+	Entries []string   `json:"entries"`
+	Names   []JarlName `json:"names"`
+	Within  []string   `json:"within"`
+}
+
+// JarlName is one of a Jarl set's names: what Jarl gave for it.
+type JarlName struct {
+	Name string `json:"name"`
+	View string `json:"view,omitempty"` // as configured ("": the only view that has it)
+	// Found is the view it was found in.
+	Found string `json:"found_view,omitempty"`
+	// Chain are the CNAME targets followed, in order.
+	Chain     []string      `json:"chain,omitempty"`
+	Addresses []JarlAddress `json:"addresses"`
+	// Problem is why Jarl's records give it no addresses.
+	Problem string `json:"problem,omitempty"`
+	// Checked is when Jarl last answered for it; Error why the last try
+	// failed (its addresses are those of Checked).
+	Checked *time.Time `json:"checked,omitempty"`
+	Error   string     `json:"error,omitempty"`
+}
+
+// JarlAddress is an address a name has in Jarl: Used if the set holds
+// it, else why not.
+type JarlAddress struct {
+	Address string `json:"address"`
+	Used    bool   `json:"used"`
+	Why     string `json:"why,omitempty"`
+}

internal/auth/auth.go

@@ -147,13 +147,14 @@ func NewSessionID() (id, csrf string) {
 const (
 	ResConfig = "config" // the firewall configuration, its history and imports
 	ResSets   = "sets"   // dynamic sets' entries (a grant may name the sets)
+	ResBans   = "bans"   // ban lists' bans (a grant may name the lists)
 	ResLog    = "log"    // counters, the drop log and the status
 	ResAudit  = "audit"  // the audit log
 	ResAll    = "*"
 )
 
 // Resources lists them in display order.
-var Resources = []string{ResConfig, ResSets, ResLog, ResAudit}
+var Resources = []string{ResConfig, ResSets, ResBans, ResLog, ResAudit}
 
 // Access levels.
 const (
@@ -163,8 +164,8 @@ const (
 
 // Roles are ready-made sets of grants.
 var Roles = map[string][]model.Grant{
-	"viewer":   {{Resource: ResConfig, Access: Read}, {Resource: ResSets, Access: Read}, {Resource: ResLog, Access: Read}},
+	"viewer":   {{Resource: ResConfig, Access: Read}, {Resource: ResSets, Access: Read}, {Resource: ResBans, Access: Read}, {Resource: ResLog, Access: Read}},
-	"operator": {{Resource: ResConfig, Access: Write}, {Resource: ResSets, Access: Write}, {Resource: ResLog, Access: Read}, {Resource: ResAudit, Access: Read}},
+	"operator": {{Resource: ResConfig, Access: Write}, {Resource: ResSets, Access: Write}, {Resource: ResBans, Access: Write}, {Resource: ResLog, Access: Read}, {Resource: ResAudit, Access: Read}},
 	"log":      {{Resource: ResLog, Access: Read}},
 }
 
@@ -179,12 +180,13 @@ func RoleNames() []string {
 }
 
 // ParseGrant reads "resource:access" ("log:read", "*:write"), and for
-// sets optionally the sets it is limited to ("sets:write:guest,portal").
+// sets and bans optionally the sets or ban lists it is limited to
+// ("sets:write:guest,portal", "bans:write:web").
 func ParseGrant(s string) (model.Grant, error) {
 	parts := strings.SplitN(strings.TrimSpace(s), ":", 3)
 	g := model.Grant{Resource: strings.ToLower(parts[0])}
 	if len(parts) < 2 {
-		return g, fmt.Errorf("grant %q: write it as resource:access, e.g. log:read, or sets:write:SET1,SET2", s)
+		return g, fmt.Errorf("grant %q: write it as resource:access, e.g. log:read, sets:write:SET1,SET2 or bans:write:LIST", s)
 	}
 	g.Access = strings.ToLower(parts[1])
 	if len(parts) == 3 {
@@ -211,8 +213,8 @@ func ValidateGrant(g *model.Grant) error {
 	if g.Access != Read && g.Access != Write {
 		return fmt.Errorf("access must be read or write, not %q", g.Access)
 	}
-	if len(g.Sets) > 0 && g.Resource != ResSets {
+	if len(g.Sets) > 0 && g.Resource != ResSets && g.Resource != ResBans {
-		return fmt.Errorf("only a sets grant can name sets (sets:write:%s)", strings.Join(g.Sets, ","))
+		return fmt.Errorf("only a sets or bans grant can name sets or ban lists (sets:write:%s)", strings.Join(g.Sets, ","))
 	}
 	return nil
 }
@@ -272,20 +274,26 @@ func covers(gs []model.Grant, resource string, write bool) bool {
 
 // CanSet reports whether the principal may read or change the entries of
 // a dynamic set: a sets grant covers it if it names no sets, or names it.
-func (p *Principal) CanSet(name string, write bool) bool {
+func (p *Principal) CanSet(name string, write bool) bool { return p.canNamed(ResSets, name, write) }
+
+// CanBan reports whether the principal may read or change the bans of a
+// ban list: a bans grant covers it if it names no lists, or names it.
+func (p *Principal) CanBan(list string, write bool) bool { return p.canNamed(ResBans, list, write) }
+
+func (p *Principal) canNamed(resource, name string, write bool) bool {
 	if p == nil || p.User == nil {
 		return false
 	}
-	allowed := p.User.Admin || coversSet(p.User.Grants, name, write)
+	allowed := p.User.Admin || coversNamed(p.User.Grants, resource, name, write)
 	if p.Token != nil && p.Token.Grants != nil {
-		allowed = allowed && coversSet(p.Token.Grants, name, write)
+		allowed = allowed && coversNamed(p.Token.Grants, resource, name, write)
 	}
 	return allowed
 }
 
-func coversSet(gs []model.Grant, name string, write bool) bool {
+func coversNamed(gs []model.Grant, resource, name string, write bool) bool {
 	for _, g := range gs {
-		if (g.Resource != ResAll && g.Resource != ResSets) || (write && g.Access != Write) {
+		if (g.Resource != ResAll && g.Resource != resource) || (write && g.Access != Write) {
 			continue
 		}
 		if len(g.Sets) == 0 {

internal/config/config.go

@@ -153,6 +153,8 @@ type Jarl struct {
 	// CACert is a PEM file with a CA to trust for Jarl's certificate.
 	CACert   string `yaml:"ca_cert"`
 	Insecure bool   `yaml:"insecure"`
+	// Refresh is how often the Jarl sets' names are read (docs/jarl.md).
+	Refresh Duration `yaml:"refresh"`
 }
 
 // Enabled reports whether a Jarl server is configured.
@@ -238,6 +240,7 @@ func Default() *Config {
 			Retention: StatsRetention{Minute: Duration(7 * 24 * time.Hour), Hour: Duration(90 * 24 * time.Hour), Day: Duration(730 * 24 * time.Hour)}},
 		Shadow: Shadow{Position: ShadowAfter},
 		Names:  Names{Enabled: true, Cache: Duration(10 * time.Minute)},
+		Jarl:   Jarl{Refresh: Duration(time.Minute)},
 		TLS:    TLS{ACME: ACME{Directory: "letsencrypt-staging", Resolvers: []string{"1.1.1.1:53", "9.9.9.9:53", "8.8.8.8:53"}, CheckPropagation: true}},
 	}
 }
@@ -320,6 +323,9 @@ func (c *Config) check() error {
 	if c.Names.Cache <= 0 {
 		return fmt.Errorf("names.cache must be a duration, such as 10m")
 	}
+	if c.Jarl.Refresh < Duration(10*time.Second) {
+		return fmt.Errorf("jarl.refresh must be a duration of 10s or more, such as 1m")
+	}
 	return nil
 }
 

internal/engine/engine.go

@@ -191,6 +191,7 @@ func (e *Engine) commit(ctx context.Context, p *auth.Principal, description stri
 	// Only report warnings the change brings; old ones are on the status
 	// page.
 	res.Warnings = newProblems(validate.Check(e.state, e.env()), problems)
+	res.Warnings = append(res.Warnings, quotaRestarts(e.state, next)...)
 	if e.Firewall != nil {
 		if err := e.Firewall.Check(ctx, next); err != nil {
 			return res, &Error{Kind: KindFirewall, Message: "nftables refused the ruleset: " + err.Error()}
@@ -230,6 +231,23 @@ func (e *Engine) commit(ctx context.Context, p *auth.Principal, description stri
 	return res, nil
 }
 
+// quotaRestarts warns of the rules whose quota starts again because they
+// now count it in a way what they used can't be carried to.
+func quotaRestarts(before, after *model.State) []validate.Problem {
+	was := map[int64]*model.Rule{}
+	for _, r := range before.Rules {
+		was[r.ID] = r
+	}
+	var out []validate.Problem
+	for _, r := range after.Rules {
+		if carry, why := model.QuotaCarry(was[r.ID], r); carry == model.QuotaRestarts {
+			out = append(out, validate.Problem{Severity: validate.Warning, Code: "quota_restarts", Object: r.Label(),
+				Message: "its quota starts again: " + why})
+		}
+	}
+	return out
+}
+
 func newProblems(before, after []validate.Problem) []validate.Problem {
 	seen := map[string]bool{}
 	for _, p := range before {
@@ -304,6 +322,24 @@ func Undo(st *model.State, h *model.HistoryEntry) error {
 	return nil
 }
 
+// Rewind applies a history entry backwards to st without Undo's check:
+// stepping back through the entries newest first brings back the
+// configuration as it was before each.
+func Rewind(st *model.State, h *model.HistoryEntry) error {
+	for i := len(h.Changes) - 1; i >= 0; i-- {
+		c := h.Changes[i]
+		if c.Kind == model.KindSettings && c.Before == nil {
+			continue
+		}
+		if err := put(st, c.Kind, c.ID, c.Before); err != nil {
+			return err
+		}
+	}
+	// put appends what it brings back; its position puts it in place.
+	st.Sort()
+	return nil
+}
+
 // Replace makes the configuration next as a whole (imports).
 func (e *Engine) Replace(ctx context.Context, p *auth.Principal, description string, opts Options, next *model.State) (*Result, error) {
 	e.mu.Lock()
@@ -462,6 +498,15 @@ func Normalize(st *model.State) {
 	for _, x := range st.Sets {
 		x.Name = strings.TrimSpace(x.Name)
 		x.Entries = normAddrs(x.Entries)
+		if j := x.Jarl; j != nil {
+			for i, n := range j.Names {
+				j.Names[i] = model.ParseJarlName(n.Name)
+				if n.View != "" {
+					j.Names[i].View = strings.TrimSpace(n.View)
+				}
+			}
+			j.Within = normAddrs(j.Within) // zone names stay as they are
+		}
 	}
 	for _, x := range st.Services {
 		x.Name = strings.TrimSpace(x.Name)
@@ -491,6 +536,12 @@ func Normalize(st *model.State) {
 		normMatch(&x.Match)
 		x.ToPort = normPorts(x.ToPort)
 	}
+	for _, b := range st.BanLists {
+		b.Name = strings.TrimSpace(b.Name)
+		b.Scope = strings.ToLower(strings.TrimSpace(b.Scope))
+		b.Hosts = normAddrs(b.Hosts)
+		b.Never = normAddrs(b.Never)
+	}
 	// Positions are fractions after insertions between rules; renumber
 	// only when two have come too close to put another between.
 	st.Sort()

internal/engine/engine_test.go

@@ -173,3 +173,49 @@ func TestPositionsStayStableUntilCrowded(t *testing.T) {
 		t.Errorf("order %v", order)
 	}
 }
+
+// TestQuotaRestartsWarns: a change that counts a quota so what it used
+// can't carry over warns; one that can (to a total, wider groups) doesn't.
+func TestQuotaRestartsWarns(t *testing.T) {
+	e := newEngine(t)
+	ctx := context.Background()
+	var id int64
+	if _, err := e.Apply(ctx, admin, "", Options{}, func(st *model.State, newID func() int64) error {
+		id = newID()
+		st.Rules = append(st.Rules, &model.Rule{ID: id, Chain: "forward", Action: "drop", Quota: &model.Quota{Bytes: 1 << 30, Over: true, PerSource: true}})
+		return nil
+	}); err != nil {
+		t.Fatal(err)
+	}
+	change := func(f func(r *model.Rule)) []string {
+		res, err := e.Apply(ctx, admin, "", Options{DryRun: true}, func(st *model.State, _ func() int64) error {
+			f(st.ByID(model.KindRule, id).(*model.Rule))
+			return nil
+		})
+		if err != nil {
+			t.Fatal(err)
+		}
+		var codes []string
+		for _, w := range res.Warnings {
+			if w.Code == "quota_restarts" {
+				codes = append(codes, w.Message)
+			}
+		}
+		return codes
+	}
+	if w := change(func(r *model.Rule) { r.Quota.PerSource, r.Quota.PerDestination = false, true }); len(w) != 1 || !strings.Contains(w[0], "per source can't be counted per destination") {
+		t.Errorf("per source to per destination: %v", w)
+	}
+	if w := change(func(r *model.Rule) { r.Quota.PerSource = false }); len(w) != 0 {
+		t.Errorf("to a total (summed): %v", w)
+	}
+	if w := change(func(r *model.Rule) { r.GroupV6 = 56 }); len(w) != 0 {
+		t.Errorf("wider groups: %v", w)
+	}
+	if w := change(func(r *model.Rule) { r.GroupV6 = 128 }); len(w) != 1 {
+		t.Errorf("finer groups: %v", w)
+	}
+	if w := change(func(r *model.Rule) { r.Quota.Bytes = 2 << 30 }); len(w) != 0 {
+		t.Errorf("another amount: %v", w)
+	}
+}

internal/importer/importer.go

@@ -1502,7 +1502,15 @@ func (im *importer) builtinOf(chain string, p *parsed) string {
 		}
 		set := &im.st.Settings
 		if p.family == "ipv6" {
-			set.OwnPrefixes = append(set.OwnPrefixes, p.src...)
+			for _, s := range p.src {
+				// Dropping link-local on an external zone loses the ISP's
+				// router adverts and DHCPv6 replies.
+				if a, err := model.ParseAddress(s); err == nil && a.Overlaps(model.LinkLocal6) {
+					im.note("antispoofing: %s left out: it holds link-local addresses, which the ISP's router adverts and DHCPv6 replies come from", s)
+					continue
+				}
+				set.OwnPrefixes = append(set.OwnPrefixes, s)
+			}
 			im.st.Settings.AntispoofV6 = nil
 		} else {
 			set.AntispoofV4 = p.src

internal/importer/importer_test.go

@@ -321,3 +321,26 @@ func TestImportMeters(t *testing.T) {
 		}
 	}
 }
+
+// TestImportAntispoofLinkLocal: link-local in an IPv6 antispoof drop is
+// left out (with a note), since it would drop the ISP's router adverts.
+func TestImportAntispoofLinkLocal(t *testing.T) {
+	js, _ := os.ReadFile("testdata/router.json")
+	txt, _ := os.ReadFile("testdata/router.txt")
+	defs, _ := os.ReadFile("testdata/router.nft")
+	own := `{"prefix": {"addr": "2a02:8013:7f3d::", "len": 48}}`
+	if !strings.Contains(string(js), own) {
+		t.Fatal("router.json has no own-prefix drop")
+	}
+	js = []byte(strings.Replace(string(js), own, `{"set": [`+own+`, {"prefix": {"addr": "fe80::", "len": 10}}]}`, 1))
+	res, err := Import(Input{JSON: js, Text: string(txt), Defines: string(defs)})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p := res.State.Settings.OwnPrefixes; len(p) != 1 || p[0] != "2a02:8013:7f3d::/48" {
+		t.Errorf("own prefixes %v", p)
+	}
+	if !strings.Contains(strings.Join(res.Notes, "\n"), "fe80::/10 left out") {
+		t.Errorf("no note: %q", res.Notes)
+	}
+}

internal/jarl/jarl.go

@@ -247,3 +247,32 @@ func (c *Client) SetTXT(ctx context.Context, name, value string, zones []Zone, s
 	}
 	return c.do(ctx, http.MethodPost, "/apply", batch{Description: desc, Ops: ops, DryRun: dryRun}, nil)
 }
+
+// ZoneInfo is a zone as Jarl lists it, of any type.
+type ZoneInfo struct {
+	ID       int64  `json:"id"`
+	Name     string `json:"name"` // "example.com."
+	View     string `json:"view,omitempty"`
+	Type     string `json:"type"`
+	InView   string `json:"in_view,omitempty"` // type in-view: the view whose zone it serves
+	Disabled bool   `json:"disabled,omitempty"`
+}
+
+// AllZones lists every zone the token can see, of any type.
+func (c *Client) AllZones(ctx context.Context) ([]ZoneInfo, error) {
+	var zs []ZoneInfo
+	return zs, c.do(ctx, http.MethodGet, "/zones", nil, &zs)
+}
+
+// Record is a record as Jarl lists it.
+type Record struct {
+	Name string `json:"name"` // "nas.example.com."
+	Type string `json:"type"`
+	Data string `json:"data"`
+}
+
+// Records lists a zone's enabled records (zone: its ID).
+func (c *Client) Records(ctx context.Context, zone int64) ([]Record, error) {
+	var rs []Record
+	return rs, c.do(ctx, http.MethodGet, fmt.Sprintf("/zones/%d/records?disabled=0", zone), nil, &rs)
+}

internal/jarlsets/jarlsets.go

@@ -0,0 +1,767 @@
+// Package jarlsets fills the sets whose addresses come from Jarl. It reads
+// the A and AAAA records of the sets' names through Jarl's API, following
+// CNAMEs within the zones Jarl holds, every minute or so, and keeps what it
+// last read (in the database too) for when Jarl can't be reached. The
+// firewall gets, for each set, the addresses that lie within what the set
+// allows (zones' connected networks, or networks it names); the others are
+// left out and reported. When what the sets hold changes, the ruleset is
+// applied again (no history entry: the configuration didn't change).
+package jarlsets
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"net/netip"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"housecarl/internal/api"
+	"housecarl/internal/jarl"
+	"housecarl/internal/model"
+	"housecarl/internal/validate"
+)
+
+// MetaKey is the database meta key holding what was last read.
+const MetaKey = "jarl_sets"
+
+// maxChain is how many CNAMEs are followed for one name.
+const maxChain = 8
+
+// Source is Jarl (internal/jarl.Client).
+type Source interface {
+	AllZones(ctx context.Context) ([]jarl.ZoneInfo, error)
+	Records(ctx context.Context, zone int64) ([]jarl.Record, error)
+}
+
+// Lookup is what Jarl gave for one name in one view.
+type Lookup struct {
+	Name      string   `json:"name"`
+	View      string   `json:"view,omitempty"`
+	Found     string   `json:"found,omitempty"`
+	Chain     []string `json:"chain,omitempty"`
+	Addresses []string `json:"addresses,omitempty"`
+	// Problem is why Jarl's records give no addresses (Jarl answered).
+	Problem string `json:"problem,omitempty"`
+	// Checked is when Jarl last answered; Error why the last try failed.
+	Checked time.Time `json:"checked"`
+	Error   string    `json:"error,omitempty"`
+}
+
+// saved is what the database keeps.
+type saved struct {
+	Lookups map[string]*Lookup `json:"lookups"`
+	// Nets are the zones' connected networks last seen, for when a zone's
+	// interfaces have no address (at boot, a link down).
+	Nets map[string][]netip.Prefix `json:"nets,omitempty"`
+}
+
+// Resolver keeps the Jarl sets' addresses.
+type Resolver struct {
+	// Source is Jarl (nil: not configured; the sets keep what was read).
+	Source Source
+	// Interval is how often Jarl is read (default a minute).
+	Interval time.Duration
+	// State is the configuration in force.
+	State func() *model.State
+	// Connected are the networks connected to the firewall, with their
+	// zones.
+	Connected func(st *model.State) map[netip.Prefix]string
+	// Apply puts the sets' new addresses in force.
+	Apply func(ctx context.Context) error
+	// Audit records a change of a set's addresses.
+	Audit func(ctx context.Context, set, detail string)
+	// Load and Save read and write the database's copy.
+	Load func(ctx context.Context) (string, error)
+	Save func(ctx context.Context, value string) error
+	Log  *slog.Logger
+
+	run  sync.Mutex // one refresh at a time
+	mu   sync.Mutex
+	data saved
+	// applied is what the ruleset in force holds (known after an apply).
+	applied map[string][]string
+	known   bool
+	read    time.Time
+	err     string
+	kick    chan struct{}
+	now     func() time.Time
+}
+
+func (r *Resolver) init() {
+	if r.data.Lookups == nil {
+		r.data.Lookups = map[string]*Lookup{}
+	}
+	if r.data.Nets == nil {
+		r.data.Nets = map[string][]netip.Prefix{}
+	}
+	if r.kick == nil {
+		r.kick = make(chan struct{}, 1)
+	}
+	if r.now == nil {
+		r.now = time.Now
+	}
+	if r.Log == nil {
+		r.Log = slog.Default()
+	}
+}
+
+// Restore reads what was saved before housecarld (or the machine)
+// stopped. Call it before the first apply.
+func (r *Resolver) Restore(ctx context.Context) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.init()
+	if r.Load == nil {
+		return
+	}
+	v, err := r.Load(ctx)
+	if err != nil || v == "" {
+		return
+	}
+	var s saved
+	if err := json.Unmarshal([]byte(v), &s); err != nil {
+		r.Log.Warn("the saved Jarl set addresses can't be read; reading Jarl again", "err", err)
+		return
+	}
+	if s.Lookups != nil {
+		r.data.Lookups = s.Lookups
+	}
+	if s.Nets != nil {
+		r.data.Nets = s.Nets
+	}
+}
+
+// Kick has the next refresh happen now (after a change of the
+// configuration: a new name).
+func (r *Resolver) Kick() {
+	r.mu.Lock()
+	r.init()
+	k := r.kick
+	r.mu.Unlock()
+	select {
+	case k <- struct{}{}:
+	default:
+	}
+}
+
+// Run reads Jarl until ctx ends.
+func (r *Resolver) Run(ctx context.Context) {
+	r.mu.Lock()
+	r.init()
+	k := r.kick
+	every := r.Interval
+	r.mu.Unlock()
+	if every <= 0 {
+		every = time.Minute
+	}
+	t := time.NewTicker(every)
+	defer t.Stop()
+	for {
+		r.Refresh(ctx)
+		select {
+		case <-ctx.Done():
+			return
+		case <-t.C:
+		case <-k:
+		}
+	}
+}
+
+// Refresh reads Jarl now and puts what changed in force.
+func (r *Resolver) Refresh(ctx context.Context) {
+	r.run.Lock()
+	defer r.run.Unlock()
+	st := r.State()
+	r.read1(ctx, st)
+	r.sync(ctx, st)
+}
+
+// needed are the names the sets of st look up, by key.
+func needed(st *model.State) map[string]model.JarlName {
+	out := map[string]model.JarlName{}
+	for _, s := range st.Sets {
+		if s.Jarl == nil {
+			continue
+		}
+		for _, n := range s.Jarl.Names {
+			out[n.String()] = n
+		}
+	}
+	return out
+}
+
+// read1 reads every name from Jarl once.
+func (r *Resolver) read1(ctx context.Context, st *model.State) {
+	names := needed(st)
+	r.mu.Lock()
+	r.init()
+	src := r.Source
+	r.mu.Unlock()
+	// The zones' networks, for when they can't be seen (Entries).
+	r.rememberNets(st)
+	if src == nil || len(names) == 0 {
+		r.mu.Lock()
+		changed := false
+		for k := range r.data.Lookups {
+			if _, ok := names[k]; !ok {
+				delete(r.data.Lookups, k)
+				changed = true
+			}
+		}
+		r.mu.Unlock()
+		if changed {
+			r.save(ctx)
+		}
+		return
+	}
+	ctx, cancel := context.WithTimeout(ctx, 30*time.Second)
+	defer cancel()
+	zones, err := src.AllZones(ctx)
+	now := r.now()
+	results := map[string]*Lookup{}
+	if err == nil {
+		l := &lookup{ctx: ctx, src: src, zones: zones, records: map[int64][]jarl.Record{}, errs: map[int64]error{}}
+		for k, n := range names {
+			results[k] = l.resolve(n)
+		}
+	}
+	r.mu.Lock()
+	if err != nil {
+		r.err = err.Error()
+	} else {
+		r.err, r.read = "", now
+	}
+	for k, n := range names {
+		old := r.data.Lookups[k]
+		res := results[k]
+		switch {
+		case res != nil && res.Error == "":
+			res.Checked = now
+			r.data.Lookups[k] = res
+		case old != nil:
+			// Keep what Jarl last said.
+			old.Error = errText(err, res)
+		default:
+			r.data.Lookups[k] = &Lookup{Name: n.Name, View: n.View, Error: errText(err, res)}
+		}
+		if err != nil || res != nil && res.Error != "" {
+			r.Log.Warn("reading a Jarl set's name failed; the set keeps the addresses it had", "name", n.String(), "err", r.data.Lookups[k].Error)
+		}
+	}
+	for k := range r.data.Lookups {
+		if _, ok := names[k]; !ok {
+			delete(r.data.Lookups, k)
+		}
+	}
+	r.mu.Unlock()
+	r.save(ctx)
+}
+
+func errText(err error, res *Lookup) string {
+	if err != nil {
+		return err.Error()
+	}
+	return res.Error
+}
+
+func (r *Resolver) save(ctx context.Context) {
+	if r.Save == nil {
+		return
+	}
+	r.mu.Lock()
+	b, err := json.Marshal(r.data)
+	r.mu.Unlock()
+	if err == nil {
+		err = r.Save(ctx, string(b))
+	}
+	if err != nil {
+		r.Log.Warn("saving the Jarl set addresses failed", "err", err)
+	}
+}
+
+// rememberNets keeps each zone's connected networks.
+func (r *Resolver) rememberNets(st *model.State) {
+	if r.Connected == nil {
+		return
+	}
+	now := zoneNets(r.Connected(st))
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	for z, ps := range now {
+		r.data.Nets[z] = ps
+	}
+}
+
+func zoneNets(conn map[netip.Prefix]string) map[string][]netip.Prefix {
+	out := map[string][]netip.Prefix{}
+	for p, z := range conn {
+		out[z] = append(out[z], p)
+	}
+	for _, ps := range out {
+		sort.Slice(ps, func(i, j int) bool { return ps[i].String() < ps[j].String() })
+	}
+	return out
+}
+
+// sync applies the ruleset again if the sets' addresses changed.
+func (r *Resolver) sync(ctx context.Context, st *model.State) {
+	want := r.Entries(st)
+	r.mu.Lock()
+	known, applied := r.known, r.applied
+	r.mu.Unlock()
+	// No Jarl sets, nothing to do (and an empty configuration is never
+	// applied: its policies would close the machine).
+	if len(want) == 0 || st.Empty() || known && sameEntries(applied, want) || r.Apply == nil {
+		return
+	}
+	if err := r.Apply(ctx); err != nil {
+		r.Log.Error("putting the Jarl sets' new addresses in force failed", "err", err)
+		return
+	}
+	for _, s := range st.Sets {
+		if s.Jarl == nil {
+			continue
+		}
+		add, del := diff(applied[s.Name], want[s.Name])
+		if len(add) == 0 && len(del) == 0 {
+			continue
+		}
+		var parts []string
+		if len(add) > 0 {
+			parts = append(parts, "added "+strings.Join(add, ", "))
+		}
+		if len(del) > 0 {
+			parts = append(parts, "removed "+strings.Join(del, ", "))
+		}
+		detail := strings.Join(parts, "; ")
+		r.Log.Info("a Jarl set's addresses changed", "set", s.Name, "change", detail)
+		if r.Audit != nil {
+			r.Audit(ctx, s.Name, detail)
+		}
+	}
+}
+
+func sameEntries(a, b map[string][]string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for k, v := range a {
+		w, ok := b[k]
+		if !ok || strings.Join(v, ",") != strings.Join(w, ",") {
+			return false
+		}
+	}
+	return true
+}
+
+func diff(old, now []string) (add, del []string) {
+	was := map[string]bool{}
+	for _, a := range old {
+		was[a] = true
+	}
+	is := map[string]bool{}
+	for _, a := range now {
+		is[a] = true
+		if !was[a] {
+			add = append(add, a)
+		}
+	}
+	for _, a := range old {
+		if !is[a] {
+			del = append(del, a)
+		}
+	}
+	return add, del
+}
+
+// Applied implements nft.JarlSets.
+func (r *Resolver) Applied(entries map[string][]string) {
+	c := map[string][]string{}
+	for k, v := range entries {
+		c[k] = append([]string(nil), v...)
+	}
+	r.mu.Lock()
+	r.applied, r.known = c, true
+	r.mu.Unlock()
+}
+
+// Entries implements nft.JarlSets: every Jarl set of st (empty or not),
+// with the addresses its names have that lie within what it allows.
+func (r *Resolver) Entries(st *model.State) map[string][]string {
+	out := map[string][]string{}
+	nets := r.nets(st)
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.init()
+	for _, s := range st.Sets {
+		if s.Jarl == nil {
+			continue
+		}
+		seen := map[string]bool{}
+		list := []string{}
+		for _, n := range s.Jarl.Names {
+			lu := r.data.Lookups[n.String()]
+			if lu == nil {
+				continue
+			}
+			for _, a := range lu.Addresses {
+				if seen[a] || allowed(a, s.Jarl.Within, nets) != "" {
+					continue
+				}
+				seen[a] = true
+				list = append(list, a)
+			}
+		}
+		sortAddrs(list)
+		out[s.Name] = list
+	}
+	return out
+}
+
+// nets are the zones' connected networks: now, or as last seen.
+func (r *Resolver) nets(st *model.State) map[string][]netip.Prefix {
+	var now map[string][]netip.Prefix
+	if r.Connected != nil {
+		now = zoneNets(r.Connected(st))
+	}
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.init()
+	out := map[string][]netip.Prefix{}
+	for _, z := range st.Zones {
+		if ps := now[z.Name]; len(ps) > 0 {
+			out[z.Name] = ps
+		} else {
+			out[z.Name] = r.data.Nets[z.Name]
+		}
+	}
+	return out
+}
+
+func sortAddrs(list []string) {
+	sort.Slice(list, func(i, j int) bool {
+		a, _ := netip.ParseAddr(list[i])
+		b, _ := netip.ParseAddr(list[j])
+		return a.Less(b)
+	})
+}
+
+// allowed says why an address isn't let in ("" if it is).
+func allowed(addr string, within []string, nets map[string][]netip.Prefix) string {
+	a, err := netip.ParseAddr(addr)
+	if err != nil {
+		return "not an address"
+	}
+	a = a.Unmap()
+	switch {
+	case a.IsUnspecified(), a.IsLoopback(), a.IsMulticast():
+		return "not a host's address (unspecified, loopback or multicast)"
+	}
+	for _, w := range within {
+		if l, err := model.ParseAddress(w); err == nil {
+			if l.Contains(a) {
+				return ""
+			}
+			continue
+		}
+		for _, p := range nets[w] {
+			if p.Contains(a) {
+				return ""
+			}
+		}
+	}
+	return "not within " + strings.Join(within, ", ")
+}
+
+// ---- looking names up
+
+// lookup reads Jarl's records for one refresh.
+type lookup struct {
+	ctx     context.Context
+	src     Source
+	zones   []jarl.ZoneInfo
+	records map[int64][]jarl.Record
+	errs    map[int64]error
+}
+
+func fqdn(n string) string {
+	n = strings.ToLower(strings.TrimSpace(n))
+	if !strings.HasSuffix(n, ".") {
+		n += "."
+	}
+	return n
+}
+
+func under(name, zone string) bool {
+	return zone == "." || name == zone || strings.HasSuffix(name, "."+zone)
+}
+
+func short(n string) string { return strings.TrimSuffix(n, ".") }
+
+// zoneFor finds the zone of Jarl's that answers for name in view ("":
+// the only view whose zones hold it). It returns the zone, the view, or
+// why there is none.
+func (l *lookup) zoneFor(name, view string) (*jarl.ZoneInfo, string, string) {
+	if view == "" {
+		views := map[string]bool{}
+		for _, z := range l.zones {
+			if z.Type != "hint" && under(name, fqdn(z.Name)) {
+				views[z.View] = true
+			}
+		}
+		switch len(views) {
+		case 0:
+			return nil, "", fmt.Sprintf("no zone in Jarl holds %s (or the token can't see it)", short(name))
+		case 1:
+			for v := range views {
+				view = v
+			}
+		default:
+			var vs []string
+			for v := range views {
+				vs = append(vs, v)
+			}
+			sort.Strings(vs)
+			return nil, "", fmt.Sprintf("%s is in Jarl's views %s: name the view, such as %s@%s", short(name), strings.Join(vs, ", "), short(name), vs[0])
+		}
+	}
+	var best *jarl.ZoneInfo
+	for i := range l.zones {
+		z := &l.zones[i]
+		zn := fqdn(z.Name)
+		if z.Type == "hint" || !strings.EqualFold(z.View, view) || !under(name, zn) {
+			continue
+		}
+		if best == nil || len(zn) > len(fqdn(best.Name)) {
+			best = z
+		}
+	}
+	where := ""
+	if view != "" {
+		where = " in view " + view
+	}
+	if best == nil {
+		return nil, view, fmt.Sprintf("no zone%s holds %s in Jarl (or the token can't see it)", where, short(name))
+	}
+	if best.Type == "in-view" {
+		var served *jarl.ZoneInfo
+		for i := range l.zones {
+			z := &l.zones[i]
+			if fqdn(z.Name) == fqdn(best.Name) && strings.EqualFold(z.View, best.InView) && z.Type != "in-view" {
+				served = z
+			}
+		}
+		if served == nil {
+			return nil, view, fmt.Sprintf("zone %s%s serves view %s's zone, which the token can't see", short(best.Name), where, best.InView)
+		}
+		best = served
+	}
+	if best.Disabled {
+		return nil, view, fmt.Sprintf("zone %s%s is disabled in Jarl", short(best.Name), where)
+	}
+	if best.Type != "primary" {
+		return nil, view, fmt.Sprintf("zone %s%s is a %s zone: Jarl doesn't hold its records", short(best.Name), where, best.Type)
+	}
+	return best, view, ""
+}
+
+func (l *lookup) zoneRecords(id int64) ([]jarl.Record, error) {
+	if err, ok := l.errs[id]; ok {
+		return nil, err
+	}
+	if rs, ok := l.records[id]; ok {
+		return rs, nil
+	}
+	rs, err := l.src.Records(l.ctx, id)
+	if err != nil {
+		l.errs[id] = err
+		return nil, err
+	}
+	l.records[id] = rs
+	return rs, nil
+}
+
+// resolve looks a name up as named would answer it in the view: its A
+// and AAAA records, or those of the names its CNAMEs lead to.
+func (l *lookup) resolve(n model.JarlName) *Lookup {
+	out := &Lookup{Name: n.Name, View: n.View}
+	name, view := fqdn(n.Name), n.View
+	seen := map[string]bool{name: true}
+	for hop := 0; ; hop++ {
+		z, v, problem := l.zoneFor(name, view)
+		if hop == 0 {
+			out.Found = v
+		}
+		if problem != "" {
+			if hop > 0 {
+				problem = fmt.Sprintf("its CNAME leads to %s, which Housecarl can't follow: %s (only names Jarl holds are followed)", short(name), problem)
+			}
+			out.Problem = problem
+			return out
+		}
+		view = v
+		recs, err := l.zoneRecords(z.ID)
+		if err != nil {
+			out.Error = err.Error()
+			return out
+		}
+		apex := fqdn(z.Name)
+		var addrs []string
+		cname := ""
+		for _, rec := range recs {
+			owner := fqdn(rec.Name)
+			switch {
+			case rec.Type == "NS" && owner != apex && under(name, owner):
+				out.Problem = fmt.Sprintf("%s is below a delegation (NS records at %s): Jarl doesn't hold its records", short(name), short(owner))
+				return out
+			case owner != name:
+			case rec.Type == "A" || rec.Type == "AAAA":
+				if a, err := netip.ParseAddr(strings.TrimSpace(rec.Data)); err == nil {
+					addrs = append(addrs, a.Unmap().String())
+				}
+			case rec.Type == "CNAME":
+				cname = target(rec.Data, apex)
+			}
+		}
+		if cname != "" {
+			if seen[cname] || len(out.Chain) >= maxChain {
+				out.Problem = fmt.Sprintf("its CNAMEs go round in a loop or are longer than %d (%s)", maxChain, strings.Join(append(out.Chain, short(cname)), " → "))
+				return out
+			}
+			seen[cname] = true
+			out.Chain = append(out.Chain, short(cname))
+			name = cname
+			continue
+		}
+		if len(addrs) == 0 {
+			if hop > 0 {
+				out.Problem = fmt.Sprintf("its CNAME leads to %s, which has no A or AAAA record in Jarl", short(name))
+			} else {
+				out.Problem = fmt.Sprintf("%s has no A, AAAA or CNAME record in Jarl (wildcards aren't followed)", short(name))
+			}
+			return out
+		}
+		sortAddrs(addrs)
+		out.Addresses = dedup(addrs)
+		return out
+	}
+}
+
+// target is a CNAME's target as an FQDN (a relative one is under the
+// zone, as in a zone file).
+func target(data, apex string) string {
+	t := strings.ToLower(strings.TrimSpace(data))
+	if strings.HasSuffix(t, ".") {
+		return t
+	}
+	if t == "@" {
+		return apex
+	}
+	if apex == "." {
+		return t + "."
+	}
+	return t + "." + apex
+}
+
+func dedup(in []string) []string {
+	var out []string
+	for i, a := range in {
+		if i == 0 || a != in[i-1] {
+			out = append(out, a)
+		}
+	}
+	return out
+}
+
+// ---- status
+
+// Status is what a Jarl set holds and why.
+func (r *Resolver) Status(st *model.State, set *model.AddressSet) api.JarlSet {
+	out := api.JarlSet{Set: set.Name, Entries: []string{}, Names: []api.JarlName{}, Within: []string{}}
+	if set.Jarl == nil {
+		return out
+	}
+	out.Within = append(out.Within, set.Jarl.Within...)
+	out.Entries = r.Entries(st)[set.Name]
+	nets := r.nets(st)
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.init()
+	out.Configured = r.Source != nil
+	if !r.read.IsZero() {
+		t := r.read
+		out.Read = &t
+	}
+	out.Error = r.err
+	for _, n := range set.Jarl.Names {
+		jn := api.JarlName{Name: n.Name, View: n.View, Addresses: []api.JarlAddress{}}
+		if lu := r.data.Lookups[n.String()]; lu != nil {
+			jn.Found, jn.Chain, jn.Problem, jn.Error = lu.Found, lu.Chain, lu.Problem, lu.Error
+			if !lu.Checked.IsZero() {
+				t := lu.Checked
+				jn.Checked = &t
+			}
+			for _, a := range lu.Addresses {
+				why := allowed(a, set.Jarl.Within, nets)
+				jn.Addresses = append(jn.Addresses, api.JarlAddress{Address: a, Used: why == "", Why: why})
+			}
+		}
+		out.Names = append(out.Names, jn)
+	}
+	return out
+}
+
+// Problems are the warnings about the Jarl sets for the status page.
+func (r *Resolver) Problems(st *model.State) []validate.Problem {
+	var out []validate.Problem
+	var sets []*model.AddressSet
+	for _, s := range st.Sets {
+		if s.Jarl != nil {
+			sets = append(sets, s)
+		}
+	}
+	if len(sets) == 0 {
+		return nil
+	}
+	r.mu.Lock()
+	configured, readErr := r.Source != nil, r.err
+	r.mu.Unlock()
+	if !configured {
+		out = append(out, validate.Problem{Severity: validate.Warning, Code: "jarl_not_configured", Object: "jarl",
+			Message: "sets take their addresses from Jarl, but housecarl.yaml names no Jarl server (jarl.server, docs/jarl.md): they keep the addresses they last had, none if Jarl was never read"})
+	} else if readErr != "" {
+		out = append(out, validate.Problem{Severity: validate.Warning, Code: "jarl_unreachable", Object: "jarl",
+			Message: "reading Jarl failed: " + readErr + "; the Jarl sets keep the addresses they had"})
+	}
+	for _, s := range sets {
+		obj := "set " + s.Name
+		for _, n := range r.Status(st, s).Names {
+			switch {
+			case n.Problem != "":
+				out = append(out, validate.Problem{Severity: validate.Warning, Code: "jarl_name", Object: obj,
+					Message: n.Name + viewSuffix(n.View) + ": " + n.Problem + "; it adds no addresses"})
+			case n.Error != "" && readErr == "":
+				out = append(out, validate.Problem{Severity: validate.Warning, Code: "jarl_unreachable", Object: obj,
+					Message: n.Name + viewSuffix(n.View) + ": reading it from Jarl failed: " + n.Error + "; it keeps the addresses it had"})
+			}
+			for _, a := range n.Addresses {
+				if !a.Used {
+					out = append(out, validate.Problem{Severity: validate.Warning, Code: "jarl_outside", Object: obj,
+						Message: fmt.Sprintf("%s%s has address %s, which is left out: %s", n.Name, viewSuffix(n.View), a.Address, a.Why)})
+				}
+			}
+		}
+	}
+	return out
+}
+
+func viewSuffix(v string) string {
+	if v == "" {
+		return ""
+	}
+	return "@" + v
+}

internal/jarlsets/jarlsets_test.go

@@ -0,0 +1,317 @@
+package jarlsets
+
+import (
+	"context"
+	"errors"
+	"io"
+	"log/slog"
+	"net/netip"
+	"reflect"
+	"strings"
+	"testing"
+
+	"housecarl/internal/jarl"
+	"housecarl/internal/model"
+)
+
+// fakeJarl is a Jarl with a few zones.
+type fakeJarl struct {
+	zones   []jarl.ZoneInfo
+	records map[int64][]jarl.Record
+	down    bool           // AllZones fails
+	broken  map[int64]bool // Records fails
+	calls   int
+}
+
+func (f *fakeJarl) AllZones(ctx context.Context) ([]jarl.ZoneInfo, error) {
+	if f.down {
+		return nil, errors.New("can't reach Jarl")
+	}
+	return f.zones, nil
+}
+
+func (f *fakeJarl) Records(ctx context.Context, id int64) ([]jarl.Record, error) {
+	f.calls++
+	if f.broken[id] {
+		return nil, errors.New("Jarl answered 500")
+	}
+	return f.records[id], nil
+}
+
+func rec(name, typ, data string) jarl.Record { return jarl.Record{Name: name, Type: typ, Data: data} }
+
+// newFake: example.com in views internal (1) and external (2), linked
+// sub-zone wg.example.com in internal (3), other.org only in internal (4),
+// a secondary (5), a disabled zone (6), an in-view zone in vps (7).
+func newFake() *fakeJarl {
+	return &fakeJarl{
+		zones: []jarl.ZoneInfo{
+			{ID: 1, Name: "example.com.", View: "internal", Type: "primary"},
+			{ID: 2, Name: "example.com.", View: "external", Type: "primary"},
+			{ID: 3, Name: "wg.example.com.", View: "internal", Type: "primary"},
+			{ID: 4, Name: "other.org.", View: "internal", Type: "primary"},
+			{ID: 5, Name: "sec.net.", View: "internal", Type: "secondary"},
+			{ID: 6, Name: "off.net.", View: "internal", Type: "primary", Disabled: true},
+			{ID: 7, Name: "other.org.", View: "vps", Type: "in-view", InView: "internal"},
+			{ID: 8, Name: ".", View: "internal", Type: "hint"},
+		},
+		records: map[int64][]jarl.Record{
+			1: {
+				rec("example.com.", "NS", "ns1.example.com."),
+				rec("nas.example.com.", "A", "10.10.0.20"),
+				rec("nas.example.com.", "A", "10.10.0.21"),
+				rec("nas.example.com.", "AAAA", "2001:db8:10::20"),
+				rec("files.example.com.", "CNAME", "nas.example.com."),
+				rec("vpn.example.com.", "CNAME", "peer1.wg.example.com."),
+				rec("ext.example.com.", "CNAME", "host.duckdns.org."),
+				rec("loop1.example.com.", "CNAME", "loop2.example.com."),
+				rec("loop2.example.com.", "CNAME", "loop1"),
+				rec("rel.example.com.", "CNAME", "nas"),
+				rec("mail.example.com.", "MX", "10 nas.example.com."),
+				rec("lab.example.com.", "NS", "ns.lab.example.com."),
+				rec("www.example.com.", "A", "10.10.0.30"),
+				rec("bad.example.com.", "A", "127.0.0.1"),
+				rec("far.example.com.", "A", "192.0.2.9"),
+				rec("dead.example.com.", "CNAME", "nothing.example.com."),
+				rec("toother.example.com.", "CNAME", "srv.other.org."),
+			},
+			2: {
+				rec("www.example.com.", "A", "203.0.113.30"),
+			},
+			3: {
+				rec("peer1.wg.example.com.", "A", "10.50.50.2"),
+			},
+			4: {
+				rec("srv.other.org.", "A", "10.10.0.40"),
+			},
+		},
+		broken: map[int64]bool{},
+	}
+}
+
+func resolveOne(t *testing.T, f *fakeJarl, s string) *Lookup {
+	t.Helper()
+	l := &lookup{ctx: context.Background(), src: f, zones: f.zones, records: map[int64][]jarl.Record{}, errs: map[int64]error{}}
+	return l.resolve(model.ParseJarlName(s))
+}
+
+func TestResolve(t *testing.T) {
+	f := newFake()
+	cases := []struct {
+		name    string
+		addrs   []string
+		chain   []string
+		problem string // part of it
+		found   string
+	}{
+		{name: "nas.example.com@internal", addrs: []string{"10.10.0.20", "10.10.0.21", "2001:db8:10::20"}, found: "internal"},
+		{name: "NAS.Example.com.@internal", addrs: []string{"10.10.0.20", "10.10.0.21", "2001:db8:10::20"}, found: "internal"},
+		{name: "files.example.com@internal", addrs: []string{"10.10.0.20", "10.10.0.21", "2001:db8:10::20"}, chain: []string{"nas.example.com"}},
+		{name: "rel.example.com@internal", addrs: []string{"10.10.0.20", "10.10.0.21", "2001:db8:10::20"}, chain: []string{"nas.example.com"}},
+		// Into the sub-zone, and into another zone of the same view.
+		{name: "vpn.example.com@internal", addrs: []string{"10.50.50.2"}, chain: []string{"peer1.wg.example.com"}},
+		{name: "toother.example.com@internal", addrs: []string{"10.10.0.40"}, chain: []string{"srv.other.org"}},
+		// Only internal has wg.example.com, but external's example.com
+		// answers for the name too (that it doesn't exist): the view must be
+		// named.
+		{name: "peer1.wg.example.com", problem: "views external, internal"},
+		{name: "srv.other.org", problem: "views internal, vps"},
+		// Views give different answers.
+		{name: "www.example.com@internal", addrs: []string{"10.10.0.30"}},
+		{name: "www.example.com@external", addrs: []string{"203.0.113.30"}},
+		{name: "www.example.com", problem: "views external, internal: name the view"},
+		{name: "www.example.com@vps", problem: "no zone in view vps holds www.example.com"},
+		// An in-view zone serves the other view's records.
+		{name: "srv.other.org@vps", addrs: []string{"10.10.0.40"}},
+		{name: "ext.example.com@internal", chain: []string{"host.duckdns.org"}, problem: "its CNAME leads to host.duckdns.org, which Housecarl can't follow"},
+		{name: "loop1.example.com@internal", problem: "loop"},
+		{name: "dead.example.com@internal", chain: []string{"nothing.example.com"}, problem: "nothing.example.com, which has no A or AAAA record"},
+		{name: "mail.example.com@internal", problem: "has no A, AAAA or CNAME record"},
+		{name: "missing.example.com@internal", problem: "has no A, AAAA or CNAME record"},
+		{name: "host.lab.example.com@internal", problem: "below a delegation (NS records at lab.example.com)"},
+		{name: "a.sec.net", problem: "is a secondary zone"},
+		{name: "a.off.net", problem: "is disabled"},
+		{name: "nowhere.test", problem: "no zone in Jarl holds nowhere.test"},
+	}
+	for _, c := range cases {
+		lu := resolveOne(t, f, c.name)
+		if lu.Error != "" {
+			t.Errorf("%s: error %s", c.name, lu.Error)
+		}
+		if !reflect.DeepEqual(lu.Addresses, c.addrs) {
+			t.Errorf("%s: addresses %v, want %v (problem %q)", c.name, lu.Addresses, c.addrs, lu.Problem)
+		}
+		if c.chain != nil && !reflect.DeepEqual(lu.Chain, c.chain) {
+			t.Errorf("%s: chain %v, want %v", c.name, lu.Chain, c.chain)
+		}
+		if c.problem == "" && lu.Problem != "" || !strings.Contains(lu.Problem, c.problem) {
+			t.Errorf("%s: problem %q, want %q", c.name, lu.Problem, c.problem)
+		}
+		if c.found != "" && lu.Found != c.found {
+			t.Errorf("%s: found in %q, want %q", c.name, lu.Found, c.found)
+		}
+	}
+}
+
+func TestResolveNoViews(t *testing.T) {
+	f := &fakeJarl{zones: []jarl.ZoneInfo{{ID: 1, Name: "lan.", Type: "primary"}},
+		records: map[int64][]jarl.Record{1: {rec("nas.lan.", "A", "192.168.1.5")}}}
+	if lu := resolveOne(t, f, "nas.lan"); !reflect.DeepEqual(lu.Addresses, []string{"192.168.1.5"}) || lu.Problem != "" {
+		t.Errorf("%+v", lu)
+	}
+}
+
+// harness is a resolver over the fake Jarl, with lan = 10.10.0.0/24 and
+// wg = 10.50.50.0/24 connected.
+type harness struct {
+	r       *Resolver
+	f       *fakeJarl
+	st      *model.State
+	conn    map[netip.Prefix]string
+	applies int
+	audits  []string
+	saved   string
+}
+
+func newHarness(sets ...*model.AddressSet) *harness {
+	h := &harness{f: newFake(), conn: map[netip.Prefix]string{
+		netip.MustParsePrefix("10.10.0.0/24"):  "lan",
+		netip.MustParsePrefix("10.50.50.0/24"): "wg",
+	}}
+	h.st = &model.State{Zones: []*model.Zone{{Name: "lan"}, {Name: "wg"}, {Name: "wan"}}, Sets: sets}
+	h.r = &Resolver{Source: h.f, State: func() *model.State { return h.st }, Log: slog.New(slog.NewTextHandler(io.Discard, nil)),
+		Connected: func(*model.State) map[netip.Prefix]string { return h.conn },
+		Apply: func(ctx context.Context) error {
+			h.applies++
+			h.r.Applied(h.r.Entries(h.st))
+			return nil
+		},
+		Audit: func(ctx context.Context, set, detail string) { h.audits = append(h.audits, set+": "+detail) },
+		Load:  func(ctx context.Context) (string, error) { return h.saved, nil },
+		Save:  func(ctx context.Context, v string) error { h.saved = v; return nil }}
+	return h
+}
+
+func jset(name string, within []string, names ...string) *model.AddressSet {
+	j := &model.JarlSource{Within: within}
+	for _, n := range names {
+		j.Names = append(j.Names, model.ParseJarlName(n))
+	}
+	return &model.AddressSet{Name: name, Jarl: j}
+}
+
+func TestWithin(t *testing.T) {
+	h := newHarness(
+		jset("nas", []string{"lan"}, "nas.example.com@internal", "vpn.example.com@internal", "bad.example.com@internal", "far.example.com@internal"),
+		jset("wide", []string{"lan", "wg", "192.0.2.0/24", "2001:db8:10::/64"}, "nas.example.com@internal", "vpn.example.com@internal", "far.example.com@internal"),
+		jset("none", []string{"lan"}, "missing.example.com@internal"),
+	)
+	h.r.Refresh(context.Background())
+	got := h.r.Entries(h.st)
+	want := map[string][]string{
+		"nas":  {"10.10.0.20", "10.10.0.21"},
+		"wide": {"10.10.0.20", "10.10.0.21", "10.50.50.2", "192.0.2.9", "2001:db8:10::20"},
+		"none": {},
+	}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("entries %v, want %v", got, want)
+	}
+	st := h.r.Status(h.st, h.st.Sets[0])
+	why := map[string]string{}
+	for _, n := range st.Names {
+		for _, a := range n.Addresses {
+			why[a.Address] = a.Why
+		}
+	}
+	if why["10.10.0.20"] != "" || !strings.Contains(why["10.50.50.2"], "not within lan") || !strings.Contains(why["127.0.0.1"], "loopback") || why["2001:db8:10::20"] == "" {
+		t.Errorf("why: %v", why)
+	}
+	codes := map[string]int{}
+	for _, p := range h.r.Problems(h.st) {
+		codes[p.Code]++
+	}
+	// nas: 3 left out (v6, wg, loopback, far = 4); wide: none; none: a name problem.
+	if codes["jarl_outside"] != 4 || codes["jarl_name"] != 1 || codes["jarl_unreachable"] != 0 {
+		t.Errorf("problems %v: %+v", codes, h.r.Problems(h.st))
+	}
+	// The lan interface loses its address: its networks as last seen count.
+	h.conn = map[netip.Prefix]string{}
+	if got := h.r.Entries(h.st)["nas"]; !reflect.DeepEqual(got, []string{"10.10.0.20", "10.10.0.21"}) {
+		t.Errorf("without lan's address: %v", got)
+	}
+}
+
+func TestKeepsWhatItHad(t *testing.T) {
+	h := newHarness(jset("nas", []string{"lan", "wg"}, "nas.example.com@internal", "peer1.wg.example.com@internal"))
+	ctx := context.Background()
+	h.r.Refresh(ctx)
+	if h.applies != 1 || len(h.audits) != 1 || !strings.Contains(h.audits[0], "added 10.10.0.20, 10.10.0.21, 10.50.50.2") {
+		t.Fatalf("first read: %d applies, audits %v", h.applies, h.audits)
+	}
+	// Nothing changed: no apply.
+	h.r.Refresh(ctx)
+	if h.applies != 1 {
+		t.Errorf("unchanged: %d applies", h.applies)
+	}
+	// Jarl down: the addresses stay, a warning says so.
+	h.f.down = true
+	h.r.Refresh(ctx)
+	if got := h.r.Entries(h.st)["nas"]; len(got) != 3 || h.applies != 1 {
+		t.Errorf("Jarl down: %v, %d applies", got, h.applies)
+	}
+	if ps := h.r.Problems(h.st); len(ps) != 2 || ps[0].Code != "jarl_unreachable" || ps[1].Code != "jarl_outside" {
+		t.Errorf("Jarl down: %+v", ps)
+	}
+	// One zone's records fail: only its name keeps the old addresses.
+	h.f.down = false
+	h.f.broken[3] = true
+	h.f.records[1][1] = rec("nas.example.com.", "A", "10.10.0.22")
+	h.r.Refresh(ctx)
+	if got := h.r.Entries(h.st)["nas"]; !reflect.DeepEqual(got, []string{"10.10.0.21", "10.10.0.22", "10.50.50.2"}) {
+		t.Errorf("one zone down: %v", got)
+	}
+	if h.applies != 2 || !strings.Contains(h.audits[1], "added 10.10.0.22; removed 10.10.0.20") {
+		t.Errorf("audits %v", h.audits)
+	}
+	// After a restart, before Jarl is read: what was saved.
+	r2 := &Resolver{Load: h.r.Load, State: h.r.State, Connected: h.r.Connected}
+	r2.Restore(ctx)
+	if got := r2.Entries(h.st)["nas"]; !reflect.DeepEqual(got, []string{"10.10.0.21", "10.10.0.22", "10.50.50.2"}) {
+		t.Errorf("restored: %v", got)
+	}
+	// Jarl answers that the name is gone: its addresses go.
+	h.f.broken[3] = false
+	h.f.records[3] = nil
+	h.r.Refresh(ctx)
+	if got := h.r.Entries(h.st)["nas"]; !reflect.DeepEqual(got, []string{"10.10.0.21", "10.10.0.22"}) {
+		t.Errorf("deleted record: %v", got)
+	}
+	// A name taken out of the set is forgotten.
+	h.st.Sets[0].Jarl.Names = h.st.Sets[0].Jarl.Names[:1]
+	h.r.Refresh(ctx)
+	if len(h.r.data.Lookups) != 1 {
+		t.Errorf("lookups %v", h.r.data.Lookups)
+	}
+}
+
+func TestNotConfigured(t *testing.T) {
+	h := newHarness(jset("nas", []string{"lan"}, "nas.example.com@internal"))
+	h.r.Source = nil
+	h.r.Refresh(context.Background())
+	if ps := h.r.Problems(h.st); len(ps) != 1 || ps[0].Code != "jarl_not_configured" {
+		t.Errorf("%+v", ps)
+	}
+	if got := h.r.Entries(h.st); !reflect.DeepEqual(got, map[string][]string{"nas": {}}) {
+		t.Errorf("%v", got)
+	}
+}
+
+// TestNoSetsNoApply: without Jarl sets nothing is applied, not even at the
+// first read (an empty configuration must never be applied).
+func TestNoSetsNoApply(t *testing.T) {
+	h := newHarness()
+	h.r.Refresh(context.Background())
+	if h.applies != 0 {
+		t.Errorf("%d applies", h.applies)
+	}
+}

internal/matrix/matrix.go

@@ -241,7 +241,7 @@ func verdictOf(action string) string {
 
 // elsewhere reports whether every address of refs (addresses, sets) lies
 // in networks connected to zones other than zone: then traffic of zone
-// can't have them. An empty list, a dynamic set, or an address the
+// can't have them. An empty list, a dynamic or Jarl set, or an address the
 // firewall isn't directly connected to (a routed network) might.
 func elsewhere(st *model.State, o Options, refs []string, zone string) bool {
 	if len(refs) == 0 || len(o.Connected) == 0 || zone == Firewall {
@@ -250,7 +250,7 @@ func elsewhere(st *model.State, o Options, refs []string, zone string) bool {
 	var entries []string
 	for _, r := range refs {
 		if s := st.Set(r); s != nil {
-			if s.Dynamic {
+			if s.Runtime() {
 				return false
 			}
 			entries = append(entries, s.Entries...)

internal/model/addr.go

@@ -6,6 +6,9 @@ import (
 	"strings"
 )
 
+// LinkLocal6 is IPv6's link-local prefix.
+var LinkLocal6 = netip.MustParsePrefix("fe80::/10")
+
 // Address is a parsed address entry: one address, a prefix or a range.
 type Address struct {
 	Prefix     netip.Prefix // a single address is a /32 or /128
@@ -32,6 +35,34 @@ func (a Address) String() string {
 	return a.Prefix.String()
 }
 
+// Contains reports whether the entry holds an address.
+func (a Address) Contains(x netip.Addr) bool {
+	x = x.Unmap()
+	if a.First.IsValid() {
+		return x.Is4() == a.First.Is4() && !x.Less(a.First) && !a.End.Less(x)
+	}
+	return a.Prefix.Contains(x)
+}
+
+// Overlaps reports whether the entry and a prefix share an address.
+func (a Address) Overlaps(p netip.Prefix) bool {
+	if !a.First.IsValid() {
+		return a.Prefix.Overlaps(p)
+	}
+	if a.First.Is4() != p.Addr().Is4() {
+		return false
+	}
+	// The prefix's first and last addresses against the range.
+	first := p.Masked().Addr()
+	last := first
+	b := last.AsSlice()
+	for i := p.Bits(); i < len(b)*8; i++ {
+		b[i/8] |= 0x80 >> (i % 8)
+	}
+	last, _ = netip.AddrFromSlice(b)
+	return !last.Less(a.First) && !a.End.Less(first)
+}
+
 // ParseAddress reads an address, a prefix (host bits must be zero) or a
 // range, IPv4 or IPv6.
 func ParseAddress(s string) (Address, error) {
@@ -56,7 +87,11 @@ func ParseAddress(s string) (Address, error) {
 		if err != nil {
 			return Address{}, fmt.Errorf("%q is not an address or prefix", s)
 		}
-		p = netip.PrefixFrom(p.Addr().Unmap(), p.Bits())
+		if p.Addr().Is4In6() {
+			// Unmapping would leave an IPv4 address with IPv6 bits
+			// (::ffff:0:0/96 as 0.0.0.0/96).
+			return Address{}, fmt.Errorf("%q is an IPv4-mapped prefix, which can't be used: write IPv4 prefixes as IPv4 (10.0.0.0/8)", s)
+		}
 		if p.Masked() != p {
 			return Address{}, fmt.Errorf("%q has host bits set; the prefix is %s", s, p.Masked())
 		}

internal/model/addr_test.go

@@ -0,0 +1,28 @@
+package model
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestParseAddress(t *testing.T) {
+	for _, c := range []struct{ in, want, err string }{
+		{in: "10.0.0.0/8", want: "10.0.0.0/8"},
+		{in: "2001:db8::/32", want: "2001:db8::/32"},
+		{in: "::ffff:10.0.0.1", want: "10.0.0.1"},
+		{in: "10.0.0.1/8", err: "host bits"},
+		{in: "::ffff:0:0/96", err: "IPv4-mapped"},
+		{in: "::ffff:10.0.0.0/104", err: "IPv4-mapped"},
+	} {
+		a, err := ParseAddress(c.in)
+		if c.err != "" {
+			if err == nil || !strings.Contains(err.Error(), c.err) {
+				t.Errorf("%s: error %v, want one saying %q", c.in, err, c.err)
+			}
+			continue
+		}
+		if err != nil || a.String() != c.want {
+			t.Errorf("%s: %q, %v; want %q", c.in, a.String(), err, c.want)
+		}
+	}
+}

internal/model/auth.go

@@ -7,9 +7,10 @@ import (
 
 // Grant gives access to one resource (see internal/auth).
 type Grant struct {
-	Resource string `json:"resource"` // config, sets, log, audit, *
+	Resource string `json:"resource"` // config, sets, bans, log, audit, *
 	Access   string `json:"access"`   // read or write (write implies read)
-	// Sets limits a "sets" grant to these dynamic sets (none: all).
+	// Sets limits a "sets" grant to these dynamic sets, and a "bans"
+	// grant to these ban lists (none: all).
 	Sets []string `json:"sets,omitempty"`
 }
 

internal/model/bans.go

@@ -0,0 +1,53 @@
+package model
+
+import (
+	"net/netip"
+	"time"
+)
+
+// Ban is an address a ban list keeps out (docs/bans.md): of every port,
+// or of one protocol and port. Bans are kept apart from the
+// configuration, like a dynamic set's entries: not in the history, and
+// not on probation.
+type Ban struct {
+	ID     int64  `json:"id"`
+	ListID int64  `json:"list_id"`
+	List   string `json:"list"`
+	// Address is what is banned: an address, or an IPv6 prefix of the
+	// list's grouping ("2001:db8:1:2::/64").
+	Address  string `json:"address"`
+	Protocol string `json:"protocol,omitempty"` // tcp or udp; "" every port
+	Port     int    `json:"port,omitempty"`
+	// Expires is when the ban ends (nil: it doesn't); Timeout the
+	// seconds it has left then.
+	Expires *time.Time `json:"expires,omitempty"`
+	Timeout int        `json:"timeout,omitempty"`
+	Created time.Time  `json:"created"`
+	// Who banned it (the user or token's name), Source the program's own
+	// name for why ("guard/ssh", "fail2ban/sshd"), Reason free text (a
+	// log line).
+	Who    string `json:"who"`
+	Source string `json:"source,omitempty"`
+	Reason string `json:"reason,omitempty"`
+}
+
+// Prefix is the banned address as a prefix.
+func (b *Ban) Prefix() (netip.Prefix, error) {
+	if p, err := netip.ParsePrefix(b.Address); err == nil {
+		return p, nil
+	}
+	a, err := netip.ParseAddr(b.Address)
+	if err != nil {
+		return netip.Prefix{}, err
+	}
+	return netip.PrefixFrom(a, a.BitLen()), nil
+}
+
+// BanAddress writes a banned prefix: an address alone when it is one
+// address, else the prefix.
+func BanAddress(p netip.Prefix) string {
+	if p.IsSingleIP() {
+		return p.Addr().String()
+	}
+	return p.String()
+}

internal/model/objects.go

@@ -1,6 +1,9 @@
 package model
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+)
 
 // Chains rules are placed in.
 const (
@@ -72,10 +75,48 @@ type AddressSet struct {
 	// Timeout is a dynamic set's default entry lifetime in seconds (0:
 	// entries stay until removed).
 	Timeout int `json:"timeout,omitempty"`
+	// Jarl makes the set's entries the addresses of names in Jarl, which
+	// housecarld reads and keeps up to date (docs/jarl.md).
+	Jarl    *JarlSource `json:"jarl,omitempty"`
 	Comment string      `json:"comment,omitempty"`
 }
 
 func (s *AddressSet) GetID() int64 { return s.ID }
+
+// Runtime reports whether the set's entries come at run time (a dynamic
+// set's, a Jarl set's) rather than from the configuration.
+func (s *AddressSet) Runtime() bool { return s.Dynamic || s.Jarl != nil }
+
+// JarlSource is where a set's addresses come from in Jarl: the A and AAAA
+// records of names (CNAMEs followed), each in a view, kept only where
+// Within allows.
+type JarlSource struct {
+	Names []JarlName `json:"names"`
+	// Within are zone names and addresses (prefixes, ranges): an address
+	// is used only if it lies in a zone's connected networks or in one of
+	// the addresses.
+	Within []string `json:"within"`
+}
+
+// JarlName is a name in Jarl, in a view ("": the only view that has it).
+type JarlName struct {
+	Name string `json:"name"` // "nas.example.com", without the final dot
+	View string `json:"view,omitempty"`
+}
+
+// String is "name" or "name@view".
+func (n JarlName) String() string {
+	if n.View == "" {
+		return n.Name
+	}
+	return n.Name + "@" + n.View
+}
+
+// ParseJarlName reads "name" or "name@view".
+func ParseJarlName(s string) JarlName {
+	name, view, _ := strings.Cut(strings.TrimSpace(s), "@")
+	return JarlName{Name: strings.TrimSuffix(strings.ToLower(strings.TrimSpace(name)), "."), View: strings.TrimSpace(view)}
+}
 func (s *AddressSet) Label() string { return s.Name }
 
 // Service is a named list of ports ("tcp/22", "udp/60000-61000") and ICMP
@@ -274,6 +315,45 @@ func (r *Rule) Groups() (v4, v6 int) {
 	return v4, v6
 }
 
+// What becomes of what a rule's quota used when the rule changes
+// (QuotaCarry).
+const (
+	QuotaKept      = ""          // counted as before: carried as it is
+	QuotaSummed    = "summed"    // per address to a total: the addresses' sum
+	QuotaRegrouped = "regrouped" // per address in wider groups: added up per group
+	QuotaRestarts  = "restarts"  // can't be carried: starts again
+)
+
+// QuotaCarry says what becomes of what old's quota used when the rule
+// becomes new (both the same rule, with quotas), and for QuotaRestarts
+// why. The amount, over and the resets don't matter: only how it counts.
+func QuotaCarry(old, new *Rule) (carry, why string) {
+	if old == nil || new == nil || old.Quota == nil || new.Quota == nil {
+		return QuotaKept, ""
+	}
+	was, is := old.Quota.PerAddress(), new.Quota.PerAddress()
+	words := map[string]string{"saddr": "per source", "daddr": "per destination", "": "in total"}
+	switch {
+	case was == "" && is == "":
+		return QuotaKept, ""
+	case is == "":
+		return QuotaSummed, ""
+	case was == "":
+		return QuotaRestarts, "a total can't be split by address, so each address starts at nothing"
+	case was != is:
+		return QuotaRestarts, "what was counted " + words[was] + " can't be counted " + words[is]
+	}
+	o4, o6 := old.Groups()
+	n4, n6 := new.Groups()
+	switch {
+	case o4 == n4 && o6 == n6:
+		return QuotaKept, ""
+	case n4 > o4 || n6 > o6:
+		return QuotaRestarts, "addresses are grouped more finely now, and a group's use can't be split"
+	}
+	return QuotaRegrouped, ""
+}
+
 // PortForward publishes a service on an inside host: incoming connections
 // to a public address and port are sent on (DNAT) to To[:ToPort], let
 // through the forward chain, and, with Hairpin, also work from inside.
@@ -353,3 +433,103 @@ func (r *Redirect) Label() string {
 	}
 	return fmt.Sprintf("redirect #%d", r.ID)
 }
+
+// Ban list scopes: what a list's bans keep the banned addresses from.
+const (
+	// BanScopeFirewall: the firewall itself (the input chain).
+	BanScopeFirewall = "firewall"
+	// BanScopeHosts: the list's hosts, behind the firewall (the forward
+	// chain, where port forwards' addresses are already translated).
+	BanScopeHosts = "hosts"
+	// BanScopeEverything: the firewall and everything behind it.
+	BanScopeEverything = "everything"
+)
+
+// BanScopes lists the scopes.
+var BanScopes = []string{BanScopeFirewall, BanScopeHosts, BanScopeEverything}
+
+// Ban lists' defaults.
+const (
+	DefaultBanTime    = 3600
+	DefaultBanMaxTime = 7 * 24 * 3600
+	DefaultBanEntries = 10000
+	DefaultBanGroupV6 = 64
+)
+
+// BanList is where a program such as Guard, or fail2ban, bans addresses
+// (docs/bans.md). The program names only the address, and perhaps a
+// protocol and ports; the list says what the address is kept from. The
+// bans themselves are kept apart from the configuration, like a dynamic
+// set's entries.
+type BanList struct {
+	ID    int64  `json:"id"`
+	Name  string `json:"name"`
+	Scope string `json:"scope"`
+	// Hosts are set names or addresses: what scope hosts protects.
+	Hosts []string `json:"hosts,omitempty"`
+	// Never are set names or addresses the list never bans.
+	Never []string `json:"never,omitempty"`
+	// DefaultTime is a ban's length in seconds when none is asked for
+	// (0: an hour); MaxTime the longest (0: a week; -1: no limit, so
+	// bans may be permanent).
+	DefaultTime int `json:"default_time,omitempty"`
+	MaxTime     int `json:"max_time,omitempty"`
+	// MaxEntries limits the bans the list holds (0: 10000).
+	MaxEntries int `json:"max_entries,omitempty"`
+	// GroupV6 is the IPv6 prefix length banned for an address (0: /64,
+	// what one customer usually gets); IPv4 addresses are banned alone.
+	GroupV6  int    `json:"group_v6,omitempty"`
+	Comment  string `json:"comment,omitempty"`
+	Disabled bool   `json:"disabled,omitempty"`
+}
+
+func (b *BanList) GetID() int64  { return b.ID }
+func (b *BanList) Label() string { return b.Name }
+
+// BanTime is the default ban length in seconds.
+func (b *BanList) BanTime() int {
+	if b.DefaultTime > 0 {
+		return b.DefaultTime
+	}
+	return DefaultBanTime
+}
+
+// BanMaxTime is the longest ban in seconds, 0 for no limit.
+func (b *BanList) BanMaxTime() int {
+	switch {
+	case b.MaxTime < 0:
+		return 0
+	case b.MaxTime > 0:
+		return b.MaxTime
+	}
+	return DefaultBanMaxTime
+}
+
+// Entries is the most bans the list holds.
+func (b *BanList) Entries() int {
+	if b.MaxEntries > 0 {
+		return b.MaxEntries
+	}
+	return DefaultBanEntries
+}
+
+// V6Group is the IPv6 prefix length an address is banned with.
+func (b *BanList) V6Group() int {
+	if b.GroupV6 > 0 {
+		return b.GroupV6
+	}
+	return DefaultBanGroupV6
+}
+
+// Covers reports whether the list's bans apply to a chain.
+func (b *BanList) Covers(chain string) bool {
+	switch b.Scope {
+	case BanScopeFirewall:
+		return chain == ChainInput
+	case BanScopeHosts:
+		return chain == ChainForward
+	case BanScopeEverything:
+		return chain == ChainInput || chain == ChainForward
+	}
+	return false
+}

internal/model/quota_test.go

@@ -0,0 +1,26 @@
+package model
+
+import "testing"
+
+func TestQuotaCarry(t *testing.T) {
+	rule := func(per string, v4, v6 int) *Rule {
+		return &Rule{GroupV4: v4, GroupV6: v6, Quota: &Quota{Bytes: 1, PerSource: per == "src", PerDestination: per == "dst"}}
+	}
+	for _, c := range []struct {
+		old, new *Rule
+		want     string
+	}{
+		{rule("", 0, 0), rule("", 0, 0), QuotaKept},
+		{rule("src", 0, 0), rule("src", 32, 64), QuotaKept}, // the defaults, written out
+		{rule("src", 0, 0), rule("", 0, 0), QuotaSummed},
+		{rule("", 0, 0), rule("src", 0, 0), QuotaRestarts},
+		{rule("src", 0, 0), rule("dst", 0, 0), QuotaRestarts},
+		{rule("src", 0, 0), rule("src", 24, 56), QuotaRegrouped},
+		{rule("src", 0, 0), rule("src", 24, 128), QuotaRestarts},
+		{nil, rule("src", 0, 0), QuotaKept},
+	} {
+		if got, _ := QuotaCarry(c.old, c.new); got != c.want {
+			t.Errorf("%+v -> %+v: %q, want %q", c.old, c.new, got, c.want)
+		}
+	}
+}

internal/model/resolve.go

@@ -1,7 +1,8 @@
 package model
 
 // FamilyRefs are a reference list's part for one address family: names of
-// sets that have entries of the family (dynamic sets always do), and
+// sets that have entries of the family (dynamic and Jarl sets always
+// do), and
 // literal entries.
 type FamilyRefs struct {
 	Sets     []string
@@ -38,10 +39,10 @@ func (st *State) SplitRefs(refs []string) (v4, v6 FamilyRefs) {
 	return v4, v6
 }
 
-// Families reports which families a set holds: a dynamic set may get
+// Families reports which families a set holds: a dynamic or Jarl set may
-// either at run time.
+// get either at run time.
 func (s *AddressSet) Families() (v4, v6 bool) {
-	if s.Dynamic {
+	if s.Runtime() {
 		return true, true
 	}
 	for _, e := range s.Entries {

internal/model/state.go

@@ -20,6 +20,7 @@ type State struct {
 	Forwards  []*PortForward `json:"forwards"`
 	SNATs     []*SourceNAT   `json:"snats"`
 	Redirects []*Redirect    `json:"redirects"`
+	BanLists  []*BanList     `json:"ban_lists"`
 }
 
 // Object kinds, for changes and the history.
@@ -32,10 +33,11 @@ const (
 	KindForward  = "forward"
 	KindSNAT     = "snat"
 	KindRedirect = "redirect"
+	KindBanList  = "banlist"
 )
 
 // Kinds lists the object kinds (not settings) in display order.
-var Kinds = []string{KindZone, KindSet, KindService, KindRule, KindForward, KindSNAT, KindRedirect}
+var Kinds = []string{KindZone, KindSet, KindService, KindRule, KindForward, KindSNAT, KindRedirect, KindBanList}
 
 // Object is anything in the State with an ID.
 type Object interface {
@@ -73,6 +75,9 @@ func (st *State) Fill() {
 	if st.Redirects == nil {
 		st.Redirects = []*Redirect{}
 	}
+	if st.BanLists == nil {
+		st.BanLists = []*BanList{}
+	}
 }
 
 // Objects returns the objects of a kind.
@@ -107,6 +112,10 @@ func (st *State) Objects(kind string) []Object {
 		for _, o := range st.Redirects {
 			out = append(out, o)
 		}
+	case KindBanList:
+		for _, o := range st.BanLists {
+			out = append(out, o)
+		}
 	}
 	return out
 }
@@ -141,6 +150,8 @@ func (st *State) Put(kind string, id int64, data json.RawMessage) error {
 		return put(&st.SNATs, id, data)
 	case KindRedirect:
 		return put(&st.Redirects, id, data)
+	case KindBanList:
+		return put(&st.BanLists, id, data)
 	}
 	return &unknownKind{kind}
 }
@@ -187,6 +198,7 @@ func (st *State) Sort() {
 	sort.SliceStable(st.Zones, func(i, j int) bool { return st.Zones[i].Name < st.Zones[j].Name })
 	sort.SliceStable(st.Sets, func(i, j int) bool { return st.Sets[i].Name < st.Sets[j].Name })
 	sort.SliceStable(st.Services, func(i, j int) bool { return st.Services[i].Name < st.Services[j].Name })
+	sort.SliceStable(st.BanLists, func(i, j int) bool { return st.BanLists[i].Name < st.BanLists[j].Name })
 	sort.SliceStable(st.Rules, func(i, j int) bool {
 		a, b := st.Rules[i], st.Rules[j]
 		if a.Chain != b.Chain {
@@ -262,7 +274,7 @@ func (st *State) ByID(kind string, id int64) Object {
 }
 
 // Find finds an object of a kind by ID or name (zones, sets, services,
-// port forwards) or by ID alone (rules, source NAT, redirects).
+// port forwards, ban lists) or by ID alone (rules, source NAT, redirects).
 func (st *State) Find(kind, ref string) Object {
 	for _, o := range st.Objects(kind) {
 		if itoa(o.GetID()) == ref {
@@ -290,6 +302,20 @@ func (st *State) Find(kind, ref string) Object {
 				return f
 			}
 		}
+	case KindBanList:
+		if b := st.BanList(ref); b != nil {
+			return b
+		}
+	}
+	return nil
+}
+
+// BanList finds a ban list by name.
+func (st *State) BanList(name string) *BanList {
+	for _, b := range st.BanLists {
+		if strings.EqualFold(b.Name, name) {
+			return b
+		}
 	}
 	return nil
 }

internal/nft/nft.go

@@ -15,6 +15,7 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"net/netip"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -189,6 +190,30 @@ func (r *Runner) DeleteElement(ctx context.Context, set, addr string) error {
 	return err
 }
 
+// AddBan puts a ban in force: added, or if it is there already, given
+// its new time (nftables keeps an element's old timeout when it is added
+// again, so it is added, deleted and added in one transaction).
+func (r *Runner) AddBan(ctx context.Context, b render.Ban) error {
+	set := render.BanSet(b.List, b.Addr.Addr().Is6(), b.Proto != "")
+	e := render.BanElement(b)
+	t := ""
+	if b.Timeout > 0 {
+		t = fmt.Sprintf(" timeout %ds", b.Timeout)
+	}
+	script := fmt.Sprintf("add element inet %[1]s %[2]s { %[3]s }\ndelete element inet %[1]s %[2]s { %[3]s }\nadd element inet %[1]s %[2]s { %[3]s%[4]s }\n", render.Table, set, e, t)
+	_, err := r.run(ctx, script, "-f", "/dev/stdin")
+	return err
+}
+
+// DeleteBan lifts a ban. One already gone (it ran out) isn't an error.
+func (r *Runner) DeleteBan(ctx context.Context, b render.Ban) error {
+	set := render.BanSet(b.List, b.Addr.Addr().Is6(), b.Proto != "")
+	e := render.BanElement(b)
+	script := fmt.Sprintf("add element inet %[1]s %[2]s { %[3]s }\ndelete element inet %[1]s %[2]s { %[3]s }\n", render.Table, set, e)
+	_, err := r.run(ctx, script, "-f", "/dev/stdin")
+	return err
+}
+
 // ---- reading JSON
 
 // Table is what Housecarl reads back from its table: counters by mark
@@ -366,7 +391,7 @@ func ParseTable(data []byte) (*Table, error) {
 				continue
 			}
 			name := strings.TrimSuffix(strings.TrimSuffix(s.Name, "_v4"), "_v6")
-			if name == s.Name || strings.HasPrefix(s.Name, "meter_") || strings.HasPrefix(s.Name, "conn_") {
+			if name == s.Name || strings.HasPrefix(s.Name, "meter_") || strings.HasPrefix(s.Name, "conn_") || render.IsBanSet(s.Name) {
 				continue
 			}
 			for _, e := range s.Elem {
@@ -424,11 +449,27 @@ type Firewall struct {
 	restore *QuotaUsage
 	// adjust are quota changes the next apply makes (AdjustQuota).
 	adjust []QuotaAdjust
+	// quotaRules are the rules with a quota in the ruleset in force, by
+	// ID: what their usage was counted by (nil before the first apply).
+	quotaRules map[int64]*model.Rule
+	// Bans returns the active bans, which every apply puts back (the
+	// database keeps them; nil: none).
+	Bans func() []render.Ban
+	// JarlSets gives the Jarl sets' addresses (nil: none).
+	JarlSets JarlSets
 	// flowDevs are the flowtable's devices in the ruleset in force, by
 	// name, with their interface index then (0: left out, missing).
 	flowDevs map[string]int
 }
 
+// JarlSets are the Jarl sets' addresses (internal/jarlsets).
+type JarlSets interface {
+	// Entries are the addresses for st's Jarl sets: set name → addresses.
+	Entries(st *model.State) map[string][]string
+	// Applied is told what an apply put in force.
+	Applied(entries map[string][]string)
+}
+
 // ifIndex is an interface's index, 0 if it doesn't exist (tests change it).
 var ifIndex = func(name string) int {
 	if i, err := net.InterfaceByName(name); err == nil {
@@ -510,6 +551,73 @@ func (u *QuotaUsage) apply(adj []QuotaAdjust) {
 	}
 }
 
+// carry keeps what quotas used when their rules now count differently
+// (model.QuotaCarry): per address to a total, the sum; to wider groups,
+// the groups' sums; what can't be carried starts again. was are the
+// rules in force before (nil: nothing to compare with).
+func (u *QuotaUsage) carry(was map[int64]*model.Rule, st *model.State) {
+	for _, r := range st.Rules {
+		old := was[r.ID]
+		carry, _ := model.QuotaCarry(old, r)
+		if carry == model.QuotaKept {
+			continue
+		}
+		name := render.QuotaName(r.ID)
+		sets := []string{name + "_v4", name + "_v6"}
+		switch carry {
+		case model.QuotaSummed:
+			var sum int64
+			for _, set := range sets {
+				for _, e := range u.QuotaSets[set] {
+					sum += e.Used
+				}
+			}
+			if u.Quotas == nil {
+				u.Quotas = map[string]int64{}
+			}
+			u.Quotas[name] = sum
+		case model.QuotaRegrouped:
+			v4, v6 := r.Groups()
+			for _, set := range sets {
+				byKey := map[string]int64{}
+				var order []string
+				for _, e := range u.QuotaSets[set] {
+					a, err := netip.ParseAddr(e.Addr)
+					if err != nil {
+						continue
+					}
+					bits := v4
+					if a.Is6() {
+						bits = v6
+					}
+					p, _ := a.Prefix(bits)
+					k := p.Addr().String()
+					if _, ok := byKey[k]; !ok {
+						order = append(order, k)
+					}
+					byKey[k] += e.Used
+				}
+				if len(order) == 0 {
+					continue
+				}
+				var es []render.Element
+				for _, k := range order {
+					es = append(es, render.Element{Addr: k, Used: byKey[k]})
+				}
+				u.QuotaSets[set] = es
+			}
+			continue
+		}
+		// What was counted the other way goes: a total, or the entries.
+		if carry != model.QuotaSummed {
+			delete(u.Quotas, name)
+		}
+		for _, set := range sets {
+			delete(u.QuotaSets, set)
+		}
+	}
+}
+
 // ResetQuota starts a rule's quota again: the named quota, or the
 // per-address quota sets (both families).
 func (f *Firewall) ResetQuota(ctx context.Context, ruleID int64, perAddress bool) error {
@@ -529,21 +637,24 @@ func (f *Firewall) ResetQuota(ctx context.Context, ruleID int64, perAddress bool
 	return nil
 }
 
-func (f *Firewall) options() render.Options {
+func (f *Firewall) options(st *model.State) render.Options {
 	o := render.Options{Shadow: f.Shadow, ShadowBefore: f.ShadowBefore}
 	if f.Interfaces != nil {
 		o.Interfaces = f.Interfaces()
 	}
+	if f.JarlSets != nil {
+		o.JarlSets = f.JarlSets.Entries(st)
+	}
 	return o
 }
 
 // Render builds the ruleset for st as Apply would.
-func (f *Firewall) Render(st *model.State) *render.Ruleset { return render.Render(st, f.options()) }
+func (f *Firewall) Render(st *model.State) *render.Ruleset { return render.Render(st, f.options(st)) }
 
 // RenderEnforcing builds the ruleset for st as Apply would outside shadow
 // mode.
 func (f *Firewall) RenderEnforcing(st *model.State) *render.Ruleset {
-	o := f.options()
+	o := f.options(st)
 	o.Shadow, o.ShadowBefore = false, false
 	return render.Render(st, o)
 }
@@ -551,7 +662,7 @@ func (f *Firewall) RenderEnforcing(st *model.State) *render.Ruleset {
 // Check implements engine.Firewall. In shadow mode it checks the
 // enforcing ruleset too, so that leaving shadow mode can't fail.
 func (f *Firewall) Check(ctx context.Context, st *model.State) error {
-	if err := f.Runner.Check(ctx, render.Render(st, f.options())); err != nil {
+	if err := f.Runner.Check(ctx, render.Render(st, f.options(st))); err != nil {
 		return err
 	}
 	if f.Shadow {
@@ -566,7 +677,7 @@ func (f *Firewall) Check(ctx context.Context, st *model.State) error {
 func (f *Firewall) Apply(ctx context.Context, st *model.State) error {
 	f.mu.Lock()
 	defer f.mu.Unlock()
-	opt := f.options()
+	opt := f.options(st)
 	var old *Table
 	if data, err := f.Runner.ListTable(ctx); err == nil {
 		if t, err := ParseTable(data); err == nil {
@@ -579,16 +690,31 @@ func (f *Firewall) Apply(ctx context.Context, st *model.State) error {
 		usage = old.QuotaUsage
 	}
 	usage.merge(f.restore)
+	usage.carry(f.quotaRules, st)
 	usage.apply(f.adjust)
 	f.adjust = nil
 	opt.Quotas, opt.QuotaSets = usage.Quotas, usage.QuotaSets
+	if f.Bans != nil {
+		opt.Bans = f.Bans()
+	}
 	if old != nil {
 		opt.DeviceSets = old.DeviceSets
 	}
 	if err := f.Runner.Apply(ctx, render.Render(st, opt)); err != nil {
 		return err
 	}
+	if f.JarlSets != nil {
+		f.JarlSets.Applied(opt.JarlSets)
+	}
 	f.restore = nil
+	f.quotaRules = map[int64]*model.Rule{}
+	for _, r := range st.Rules {
+		if r.Quota != nil {
+			c, q := *r, *r.Quota // only the quota and the grouping are read
+			c.Quota = &q
+			f.quotaRules[r.ID] = &c
+		}
+	}
 	f.flowDevs = map[string]int{}
 	for _, d := range st.Settings.FlowtableDevices {
 		if opt.Interfaces == nil || opt.Interfaces[d] {
@@ -628,7 +754,16 @@ func pruneCounters(base map[string]Counter, st *model.State) {
 	for _, x := range st.Redirects {
 		ids[fmt.Sprintf("d%d", x.ID)] = true
 	}
+	for _, x := range st.BanLists {
+		ids[render.BanMark(x.ID)] = true
+	}
 	for mark := range base {
+		if strings.HasPrefix(mark, "ban") && strings.Trim(mark[3:], "0123456789") == "" {
+			if !ids[mark] {
+				delete(base, mark)
+			}
+			continue
+		}
 		obj, _, _ := strings.Cut(mark, "-") // f3-hairpin, f3-6 are f3's
 		if len(obj) < 2 || !strings.ContainsRune("rfsd", rune(obj[0])) || strings.Trim(obj[1:], "0123456789") != "" {
 			continue // b-established, p-input
@@ -659,7 +794,13 @@ func (f *Firewall) SaveBoot(st *model.State) error {
 	if err := writeAtomic(FallbackFile(f.BootFile), fallback); err != nil {
 		return err
 	}
-	rs := render.Render(st, render.Options{Interfaces: map[string]bool{}, Shadow: f.Shadow, ShadowBefore: f.ShadowBefore})
+	opt := render.Options{Interfaces: map[string]bool{}, Shadow: f.Shadow, ShadowBefore: f.ShadowBefore}
+	if f.JarlSets != nil {
+		// The addresses last read from Jarl: Jarl may not be reachable yet
+		// at boot.
+		opt.JarlSets = f.JarlSets.Entries(st)
+	}
+	rs := render.Render(st, opt)
 	return writeAtomic(f.BootFile, rs.Text)
 }
 
@@ -711,6 +852,14 @@ func (f *Firewall) AddElement(ctx context.Context, set, addr string, timeout int
 	return f.Runner.AddElement(ctx, set, addr, timeout)
 }
 
+// AddBan puts a ban in force (Runner.AddBan).
+func (f *Firewall) AddBan(ctx context.Context, b render.Ban) error { return f.Runner.AddBan(ctx, b) }
+
+// DeleteBan lifts a ban (Runner.DeleteBan).
+func (f *Firewall) DeleteBan(ctx context.Context, b render.Ban) error {
+	return f.Runner.DeleteBan(ctx, b)
+}
+
 // DeleteElement removes an entry from a dynamic set.
 func (f *Firewall) DeleteElement(ctx context.Context, set, addr string) error {
 	return f.Runner.DeleteElement(ctx, set, addr)

internal/nft/nft_test.go

@@ -3,6 +3,7 @@ package nft
 import (
 	"context"
 	"fmt"
+	"net/netip"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -130,6 +131,60 @@ func TestFirewallInContainer(t *testing.T) {
 	}
 }
 
+// fakeJarlSets gives fixed Jarl set addresses.
+type fakeJarlSets struct {
+	entries, applied map[string][]string
+}
+
+func (f *fakeJarlSets) Entries(*model.State) map[string][]string { return f.entries }
+func (f *fakeJarlSets) Applied(e map[string][]string)            { f.applied = e }
+
+// TestJarlSetsInContainer: a Jarl set gets its addresses with each apply,
+// and the new ones replace the old.
+func TestJarlSetsInContainer(t *testing.T) {
+	image := os.Getenv("HOUSECARL_NFT_IMAGE")
+	if image == "" {
+		t.Skip("HOUSECARL_NFT_IMAGE not set")
+	}
+	name := "housecarl-nft-jarl-test"
+	exec.Command("docker", "rm", "-f", name).Run()
+	if out, err := exec.Command("docker", "run", "-d", "--name", name, "--cap-add", "NET_ADMIN", image, "sleep", "300").CombinedOutput(); err != nil {
+		t.Fatalf("starting the container: %v %s", err, out)
+	}
+	t.Cleanup(func() { exec.Command("docker", "rm", "-f", name).Run() })
+	js := &fakeJarlSets{entries: map[string][]string{"nas": {"10.0.0.5", "10.0.0.6", "2001:db8::5"}}}
+	fw := &Firewall{Runner: &Runner{Command: []string{"docker", "exec", "-i", name, "nft"}}, JarlSets: js}
+	ctx := context.Background()
+	st := model.NewState()
+	st.Zones = []*model.Zone{{ID: 1, Name: "lan", Interfaces: []string{"eth0"}}}
+	st.Sets = []*model.AddressSet{{ID: 2, Name: "nas", Jarl: &model.JarlSource{Names: []model.JarlName{{Name: "nas.example.com"}}, Within: []string{"lan"}}}}
+	st.Rules = []*model.Rule{{ID: 3, Chain: model.ChainOutput, Position: 1, Action: model.ActionAccept, Match: model.Match{Destinations: []string{"nas"}}}}
+	elems := func() string {
+		tb, err := fw.Table(ctx)
+		if err != nil {
+			t.Fatal(err)
+		}
+		var got []string
+		for _, e := range tb.Elements["nas"] {
+			got = append(got, e.Addr)
+		}
+		return strings.Join(got, ",")
+	}
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatalf("apply: %v", err)
+	}
+	if got := elems(); got != "10.0.0.5,10.0.0.6,2001:db8::5" || len(js.applied["nas"]) != 3 {
+		t.Errorf("after apply: %s (applied %v)", got, js.applied)
+	}
+	js.entries = map[string][]string{"nas": {"10.0.0.7"}}
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatalf("reapply: %v", err)
+	}
+	if got := elems(); got != "10.0.0.7" {
+		t.Errorf("after the addresses changed: %s", got)
+	}
+}
+
 // TestQuotasInContainer: quotas keep what they used across a reload,
 // reset by hand, and come back after a reboot from what was saved.
 func TestQuotasInContainer(t *testing.T) {
@@ -197,6 +252,21 @@ func TestQuotasInContainer(t *testing.T) {
 	if t2, d2 := used(); t2 > total-1000 || t2 < total-2000 || d2 != 0 {
 		t.Errorf("after giving back: total %d (was %d, gave 1000), per destination %d (was %d, reset)", t2, total, d2, dev)
 	}
+	// Counted in total now: what the addresses used carries over.
+	ping("127.0.0.3")
+	_, dev = used()
+	st.Rules[1].Quota.PerDestination = false
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatal(err)
+	}
+	tb, _ := fw.Table(ctx)
+	if tb.Quotas["quota_r2"] < dev || dev == 0 {
+		t.Errorf("per destination to a total: %d, was %d", tb.Quotas["quota_r2"], dev)
+	}
+	st.Rules[1].Quota.PerDestination = true
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatal(err)
+	}
 	// Reset by hand.
 	if err := fw.ResetQuota(ctx, 1, false); err != nil {
 		t.Fatal(err)
@@ -211,7 +281,7 @@ func TestQuotasInContainer(t *testing.T) {
 	// saved usage comes back.
 	ping("127.0.0.2")
 	ping("127.0.0.3")
-	tb, _ := fw.Table(ctx)
+	tb, _ = fw.Table(ctx)
 	saved := tb.QuotaUsage
 	exec.Command("docker", "exec", name, "nft", "delete", "table", "inet", "housecarl").Run()
 	fw.RestoreQuotas(&saved)
@@ -240,6 +310,45 @@ func TestQuotaAdjust(t *testing.T) {
 	}
 }
 
+// TestQuotaCarry: usage follows a rule counting its quota differently.
+func TestQuotaCarry(t *testing.T) {
+	perSource := &model.Rule{ID: 2, Quota: &model.Quota{Bytes: 1 << 30, PerSource: true}}
+	usage := func() QuotaUsage {
+		return QuotaUsage{Quotas: map[string]int64{}, QuotaSets: map[string][]render.Element{
+			"quota_r2_v4": {{Addr: "10.0.0.1", Used: 100}, {Addr: "10.0.0.2", Used: 50}},
+			"quota_r2_v6": {{Addr: "2001:db8:0:1::", Used: 7}, {Addr: "2001:db8:0:2::", Used: 3}}}}
+	}
+	was := map[int64]*model.Rule{2: perSource}
+	with := func(f func(r *model.Rule)) *model.State {
+		r := *perSource
+		q := *perSource.Quota
+		r.Quota = &q
+		f(&r)
+		return &model.State{Rules: []*model.Rule{&r}}
+	}
+	u := usage()
+	u.carry(was, with(func(r *model.Rule) { r.Quota.PerSource = false }))
+	if u.Quotas["quota_r2"] != 160 || len(u.QuotaSets["quota_r2_v4"]) != 0 {
+		t.Errorf("to a total: %+v", u)
+	}
+	u = usage()
+	u.carry(was, with(func(r *model.Rule) { r.GroupV4, r.GroupV6 = 24, 48 }))
+	want := map[string][]render.Element{"quota_r2_v4": {{Addr: "10.0.0.0", Used: 150}}, "quota_r2_v6": {{Addr: "2001:db8::", Used: 10}}}
+	if !reflect.DeepEqual(u.QuotaSets, want) {
+		t.Errorf("wider groups: %+v", u.QuotaSets)
+	}
+	u = usage()
+	u.carry(was, with(func(r *model.Rule) { r.Quota.PerSource, r.Quota.PerDestination = false, true }))
+	if len(u.QuotaSets) != 0 {
+		t.Errorf("per destination now: %+v", u.QuotaSets)
+	}
+	u = usage()
+	u.carry(nil, with(func(r *model.Rule) { r.Quota.PerSource = false }))
+	if len(u.QuotaSets["quota_r2_v4"]) != 2 || u.Quotas["quota_r2"] != 0 {
+		t.Errorf("nothing to compare with (the first apply): %+v", u)
+	}
+}
+
 // TestDeviceCountsInContainer: the per-device counters are read back and
 // survive a reload.
 func TestDeviceCountsInContainer(t *testing.T) {
@@ -489,3 +598,66 @@ func TestPruneCounters(t *testing.T) {
 		t.Errorf("kept %v", got)
 	}
 }
+
+// TestBansInContainer: a ban goes in, a second one renews its time, a
+// reload keeps the bans the database has, and lifting one already gone
+// isn't an error.
+func TestBansInContainer(t *testing.T) {
+	image := os.Getenv("HOUSECARL_NFT_IMAGE")
+	if image == "" {
+		t.Skip("HOUSECARL_NFT_IMAGE not set")
+	}
+	name := "housecarl-nft-bans"
+	exec.Command("docker", "rm", "-f", name).Run()
+	if out, err := exec.Command("docker", "run", "-d", "--name", name, "--cap-add", "NET_ADMIN", image, "sleep", "300").CombinedOutput(); err != nil {
+		t.Fatalf("starting the container: %v %s", err, out)
+	}
+	t.Cleanup(func() { exec.Command("docker", "rm", "-f", name).Run() })
+	var active []render.Ban
+	fw := &Firewall{Runner: &Runner{Command: []string{"docker", "exec", "-i", name, "nft"}}, Bans: func() []render.Ban { return active }}
+	ctx := context.Background()
+	st := model.NewState()
+	st.Zones = []*model.Zone{{ID: 1, Name: "wan", Interfaces: []string{"eth0"}, External: true}}
+	st.BanLists = []*model.BanList{{ID: 2, Name: "router", Scope: model.BanScopeFirewall}}
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatalf("apply: %v", err)
+	}
+	list := func(set string) string {
+		out, _ := exec.Command("docker", "exec", name, "nft", "list", "set", "inet", "housecarl", set).CombinedOutput()
+		return string(out)
+	}
+	b := render.Ban{List: 2, Addr: netip.MustParsePrefix("203.0.113.9/32"), Timeout: 60}
+	if err := fw.AddBan(ctx, b); err != nil {
+		t.Fatal(err)
+	}
+	b.Timeout = 7200
+	if err := fw.AddBan(ctx, b); err != nil {
+		t.Fatalf("renewing: %v", err)
+	}
+	if got := list("ban_2_v4"); !strings.Contains(got, "203.0.113.9 timeout 2h") {
+		t.Errorf("renewed ban: %s", got)
+	}
+	svc := render.Ban{List: 2, Addr: netip.MustParsePrefix("2001:db8:1:2::/64"), Proto: "tcp", Port: 22}
+	if err := fw.AddBan(ctx, svc); err != nil {
+		t.Fatal(err)
+	}
+	active = []render.Ban{svc}
+	if err := fw.Apply(ctx, st); err != nil {
+		t.Fatalf("reapply: %v", err)
+	}
+	if got := list("ban_2_v6_svc"); !strings.Contains(got, "2001:db8:1:2:: . 6 . 22") {
+		t.Errorf("after a reload, the database's ban: %s", got)
+	}
+	if got := list("ban_2_v4"); strings.Contains(got, "203.0.113.9") {
+		t.Errorf("after a reload, a ban the database doesn't have: %s", got)
+	}
+	if err := fw.DeleteBan(ctx, svc); err != nil {
+		t.Fatal(err)
+	}
+	if err := fw.DeleteBan(ctx, svc); err != nil {
+		t.Errorf("lifting a ban already gone: %v", err)
+	}
+	if got := list("ban_2_v6_svc"); strings.Contains(got, "2001:db8") {
+		t.Errorf("lifted ban: %s", got)
+	}
+}

internal/render/bans.go

@@ -0,0 +1,139 @@
+package render
+
+import (
+	"fmt"
+	"net/netip"
+	"strings"
+
+	"housecarl/internal/model"
+)
+
+// Ban is an active ban, for rendering (Options.Bans): its list, the
+// address banned (an IPv4 address, or an IPv6 prefix of the list's
+// grouping), and for a ban of one port its protocol and port. Timeout is
+// the seconds it has left (0: it doesn't end).
+type Ban struct {
+	List    int64
+	Addr    netip.Prefix
+	Proto   string // "tcp", "udp", or "" for every port
+	Port    int
+	Timeout int
+}
+
+// BanSet is the name of a ban list's set for a family, and with svc
+// true its set of bans of one port.
+func BanSet(list int64, v6, svc bool) string {
+	name := fmt.Sprintf("ban_%d_v4", list)
+	if v6 {
+		name = fmt.Sprintf("ban_%d_v6", list)
+	}
+	if svc {
+		name += "_svc"
+	}
+	return name
+}
+
+// BanMark is the mark (comment "hc:ban3") of a ban list's rules.
+func BanMark(list int64) string { return fmt.Sprintf("ban%d", list) }
+
+// BanElement is the set element of a ban: "203.0.113.9", or
+// "203.0.113.9 . tcp . 22".
+func BanElement(b Ban) string {
+	e := b.Addr.Addr().String()
+	if b.Proto != "" {
+		e += fmt.Sprintf(" . %s . %d", b.Proto, b.Port)
+	}
+	return e
+}
+
+// IsBanSet reports whether a set is a ban list's.
+func IsBanSet(name string) bool { return strings.HasPrefix(name, "ban_") }
+
+// banSets declares the ban lists' sets.
+func (r *renderer) banSets() {
+	for _, b := range r.st.BanLists {
+		if b.Disabled {
+			continue
+		}
+		obj := "ban list " + b.Name
+		for _, v6 := range []bool{false, true} {
+			r.w.emit(obj, "\tset %s { type %s; flags timeout; }", BanSet(b.ID, v6, false), addrType(v6))
+			r.w.emit(obj, "\tset %s { type %s . inet_proto . inet_service; flags timeout; }", BanSet(b.ID, v6, true), addrType(v6))
+		}
+	}
+}
+
+// banRules writes the drops of the ban lists that cover a chain, ahead
+// of everything that accepts: a banned address's established connections
+// are cut too.
+func (r *renderer) banRules(chain string) {
+	for _, b := range r.st.BanLists {
+		if b.Disabled || !b.Covers(chain) {
+			continue
+		}
+		obj := "ban list " + b.Name
+		d4, d6 := r.st.SplitRefs(b.Hosts)
+		for _, fam := range []string{"v4", "v6"} {
+			dsts := []string{""}
+			if b.Scope == model.BanScopeHosts {
+				refs := d4
+				if fam == "v6" {
+					refs = d6
+				}
+				var ok bool
+				if dsts, ok = addrAlts(fam, "daddr", refs, true, false); !ok {
+					continue
+				}
+			}
+			key := ipKeyword(fam) + " saddr"
+			if fam == "v6" && b.V6Group() < 128 {
+				key += " and " + v6Mask(b.V6Group())
+			}
+			v6 := fam == "v6"
+			for _, d := range dsts {
+				r.banDrop(obj, b.ID, strings.Join(nonEmpty([]string{d, key + " @" + BanSet(b.ID, v6, false)}), " "))
+				r.banDrop(obj, b.ID, strings.Join(nonEmpty([]string{d, key + " . meta l4proto . th dport @" + BanSet(b.ID, v6, true)}), " "))
+			}
+		}
+	}
+}
+
+// banDrop writes one drop of a ban list, or in shadow mode counts it.
+func (r *renderer) banDrop(obj string, list int64, match string) {
+	if r.opt.Shadow {
+		r.w.emit(obj, "\t\t%s counter accept comment \"hc:%s %s\"", match, BanMark(list), Would("drop"))
+		return
+	}
+	r.w.emit(obj, "\t\t%s counter drop comment \"hc:%s\"", match, BanMark(list))
+}
+
+// v6Mask is the mask of an IPv6 prefix length: 64 → ffff:ffff:ffff:ffff::.
+func v6Mask(bits int) string {
+	mask := make([]byte, 16)
+	for i := 0; i < bits; i++ {
+		mask[i/8] |= 0x80 >> (i % 8)
+	}
+	m, _ := netip.AddrFromSlice(mask)
+	return m.String()
+}
+
+// banElements adds the active bans, with the time each has left, so a
+// reload keeps them.
+func (r *renderer) banElements() {
+	for _, ban := range r.opt.Bans {
+		var list *model.BanList
+		for _, b := range r.st.BanLists {
+			if b.ID == ban.List && !b.Disabled {
+				list = b
+			}
+		}
+		if list == nil || !ban.Addr.IsValid() {
+			continue
+		}
+		timeout := ""
+		if ban.Timeout > 0 {
+			timeout = fmt.Sprintf(" timeout %ds", ban.Timeout)
+		}
+		r.w.emit("ban list "+list.Name, "add element inet %s %s { %s%s }", Table, BanSet(list.ID, ban.Addr.Addr().Is6(), ban.Proto != ""), BanElement(ban), timeout)
+	}
+}

internal/render/render.go

@@ -50,6 +50,11 @@ type Options struct {
 	// DeviceSets are the per-device traffic counters' entries
 	// (stats_up_v4 …), so a reload keeps them.
 	DeviceSets map[string][]Element
+	// Bans are the ban lists' active bans, added to their sets.
+	Bans []Ban
+	// JarlSets are the Jarl sets' addresses (set name → addresses, both
+	// families), as Jarl gave them and within allows.
+	JarlSets map[string][]string
 	// Shadow renders for shadow mode: nothing is blocked, rejected,
 	// translated or changed (see the package comment).
 	Shadow bool
@@ -137,6 +142,7 @@ func (r *renderer) render() {
 	w.emit("", "delete table inet %s", Table)
 	w.emit("", "table inet %s {", Table)
 	r.sets()
+	r.banSets()
 	r.deviceSets()
 	devices := r.flowtableDevices()
 	if len(devices) > 0 {
@@ -165,6 +171,7 @@ func (r *renderer) render() {
 	w.line = base + chains.line
 	w.emit("", "}")
 	r.elements()
+	r.banElements()
 }
 
 // ---- sets
@@ -182,6 +189,10 @@ func (r *renderer) sets() {
 			}
 			continue
 		}
+		if s.Jarl != nil {
+			r.jarlSet(s)
+			continue
+		}
 		has4, has6 := s.Families()
 		for _, v6 := range []bool{false, true} {
 			if v6 && !has6 || !v6 && !has4 {
@@ -193,6 +204,26 @@ func (r *renderer) sets() {
 	}
 }
 
+// jarlSet declares a Jarl set's two sets with the addresses it has now
+// (none yet: empty, so its rules match nothing).
+func (r *renderer) jarlSet(s *model.AddressSet) {
+	for _, v6 := range []bool{false, true} {
+		var elems []string
+		for _, e := range r.opt.JarlSets[s.Name] {
+			if a, err := model.ParseAddress(e); err == nil && a.IsV6() == v6 {
+				elems = append(elems, a.String())
+			}
+		}
+		if len(elems) == 0 {
+			r.w.emit("set "+s.Name, "\tset %s { type %s; }", setName(s.Name, v6), addrType(v6))
+			continue
+		}
+		// Single addresses: no interval flag, so they stay as they are
+		// (auto-merge would join neighbours into ranges).
+		r.w.emit("set "+s.Name, "\tset %s { type %s; elements = { %s } }", setName(s.Name, v6), addrType(v6), strings.Join(elems, ", "))
+	}
+}
+
 func (r *renderer) elements() {
 	names := make([]string, 0, len(r.opt.Elements))
 	for n := range r.opt.Elements {
@@ -382,6 +413,7 @@ func (r *renderer) input() {
 	if b.Loopback {
 		r.builtin("loopback", "iifname \"lo\" accept")
 	}
+	r.banRules(model.ChainInput)
 	// Rules that count traffic see every packet: before the established
 	// connections are accepted.
 	r.rules(model.ChainInput, true)
@@ -411,6 +443,7 @@ func (r *renderer) forward(flowtable bool) {
 	st := r.st
 	b := st.Settings.Builtins
 	r.chain("forward", "forward", "filter", st.Settings.ForwardPolicy)
+	r.banRules(model.ChainForward)
 	ext := st.ExternalInterfaces()
 	// Shadow mode changes no packet.
 	if b.MSSClamp && len(ext) > 0 && !r.opt.Shadow {

internal/render/render_test.go

@@ -3,6 +3,7 @@ package render
 import (
 	"context"
 	"fmt"
+	"net/netip"
 	"os"
 	"os/exec"
 	"strings"
@@ -34,6 +35,8 @@ func router() *model.State {
 		{ID: next(), Name: "wg_admins", Entries: []string{"10.50.50.3", "10.50.50.6"}},
 		{ID: next(), Name: "dns_servers", Entries: []string{"10.0.10.5", "217.155.8.194", "fdab:abab:abab:10::5", "2a02:8013:7f3d:10::5"}},
 		{ID: next(), Name: "guests", Dynamic: true, Timeout: 3600},
+		{ID: next(), Name: "nas", Jarl: &model.JarlSource{Names: []model.JarlName{{Name: "nas.example.com", View: "internal"}}, Within: []string{"lan"}}},
+		{ID: next(), Name: "printers", Jarl: &model.JarlSource{Names: []model.JarlName{{Name: "printer.example.com"}}, Within: []string{"lan"}}},
 	}
 	st.Services = []*model.Service{
 		{ID: next(), Name: "jarl", Entries: []string{"tcp/8053"}},
@@ -66,6 +69,7 @@ func router() *model.State {
 	rule(model.ChainForward, model.Rule{Match: model.Match{InZones: []string{"wan"}}, Action: model.ActionDrop, Comment: "nothing else in"})
 	rule(model.ChainForward, model.Rule{Match: model.Match{Destinations: []string{"wg_net"}}, Action: model.ActionDrop})
 	rule(model.ChainForward, model.Rule{Match: model.Match{Services: []string{"ping"}}})
+	rule(model.ChainForward, model.Rule{Match: model.Match{InZones: []string{"wg"}, Destinations: []string{"nas", "printers"}}, Comment: "from Jarl"})
 	rule(model.ChainForward, model.Rule{Match: model.Match{Sources: []string{"wg_net", "trusted", "guests"}}})
 	// Bandwidth: a byte rate, per destination; per /24; quotas, total and
 	// per device.
@@ -95,10 +99,31 @@ func router() *model.State {
 	st.Redirects = []*model.Redirect{
 		{ID: next(), Position: 1, Match: model.Match{InZones: []string{"lan"}, NotDests: true, Destinations: []string{"10.0.10.5"}, Services: []string{"udp/53"}}, Comment: "force DNS"},
 	}
+	st.BanLists = []*model.BanList{
+		{ID: next(), Name: "router", Scope: model.BanScopeFirewall, Never: []string{"trusted"}},
+		{ID: next(), Name: "web", Scope: model.BanScopeHosts, Hosts: []string{"10.0.10.57", "2a02:8013:7f3d:10::57", "dns_servers"}},
+		{ID: next(), Name: "edge", Scope: model.BanScopeEverything, GroupV6: 48},
+		{ID: next(), Name: "off", Scope: model.BanScopeEverything, Disabled: true},
+	}
 	st.Sort()
 	return st
 }
 
+// jarlOptions are the Jarl sets' addresses.
+var jarlOptions = map[string][]string{"nas": {"10.0.10.20", "10.0.10.21", "2a02:8013:7f3d:10::20"}, "printers": {}}
+
+// banOptions are active bans in each ban list, of every port and of one.
+func banOptions(st *model.State) []Ban {
+	var out []Ban
+	for _, b := range st.BanLists {
+		out = append(out,
+			Ban{List: b.ID, Addr: netip.MustParsePrefix("203.0.113.9/32"), Timeout: 3000},
+			Ban{List: b.ID, Addr: netip.MustParsePrefix("2001:db8:1:2::/64"), Proto: "tcp", Port: 22},
+			Ban{List: b.ID, Addr: netip.MustParsePrefix("198.51.100.7/32"), Proto: "udp", Port: 53, Timeout: 60})
+	}
+	return out
+}
+
 // quotaOptions carries quota usage, as a reload does: the guest quota's,
 // and two devices' of the per-device quota.
 func quotaOptions(st *model.State) (map[string]int64, map[string][]Element) {
@@ -118,13 +143,19 @@ func quotaOptions(st *model.State) (map[string]int64, map[string][]Element) {
 func TestRenderRouter(t *testing.T) {
 	st := router()
 	q, qs := quotaOptions(st)
-	rs := Render(st, Options{Elements: map[string][]Element{"guests": {{Addr: "10.0.30.5", Timeout: 1700}}}, Quotas: q, QuotaSets: qs})
+	rs := Render(st, Options{Elements: map[string][]Element{"guests": {{Addr: "10.0.30.5", Timeout: 1700}}}, Quotas: q, QuotaSets: qs, JarlSets: jarlOptions})
 	text := rs.Text
 	for _, want := range []string{
 		"table inet housecarl {}\ndelete table inet housecarl\ntable inet housecarl {",
 		`set trusted_v4 { type ipv4_addr; flags interval; auto-merge; elements = { 10.0.10.0/24, 10.20.30.0/24, 10.50.50.0/24 } }`,
 		`set trusted_v6 { type ipv6_addr; flags interval; auto-merge; elements = { 2a02:8013:7f3d:10::/64 } }`,
 		`set guests_v4 { type ipv4_addr; flags timeout; timeout 3600s; }`,
+		// Jarl sets: their addresses now, or empty.
+		`set nas_v4 { type ipv4_addr; elements = { 10.0.10.20, 10.0.10.21 } }`,
+		`set nas_v6 { type ipv6_addr; elements = { 2a02:8013:7f3d:10::20 } }`,
+		"set printers_v4 { type ipv4_addr; }\n",
+		`iifname "wg0" ip daddr @nas_v4 counter accept`,
+		`iifname "wg0" ip6 daddr @printers_v6 counter accept`,
 		`iifname "wan" ip saddr { 0.0.0.0/8,`,
 		`iifname "wan" ip6 saddr { ::1/128, ::/128, fc00::/7, 2001:db8::/32, ff00::/8, 2a02:8013:7f3d::/48 } counter drop`,
 		`oifname "wan" tcp flags syn tcp option maxseg size set rt mtu comment "hc:b-mss-clamp"`,
@@ -257,9 +288,9 @@ func TestRenderedRulesetPassesNft(t *testing.T) {
 		q, qs := quotaOptions(st)
 		// Enforcing, and in shadow mode after and before other tables.
 		for _, mode := range []Options{{}, {Shadow: true}, {Shadow: true, ShadowBefore: true}} {
-			opt := Options{Elements: map[string][]Element{"guests": {{Addr: "10.0.30.5", Timeout: 1700}, {Addr: "2a02:8013:7f3d:30::5"}}}, Quotas: q, QuotaSets: qs,
+			opt := Options{Elements: map[string][]Element{"guests": {{Addr: "10.0.30.5", Timeout: 1700}, {Addr: "2a02:8013:7f3d:30::5"}}}, Quotas: q, QuotaSets: qs, Bans: banOptions(st),
 				DeviceSets: map[string][]Element{"stats_up_v4": {{Addr: "10.0.10.5", Timeout: 3000, Packets: 7, Bytes: 7000}}, "stats_down_v6": {{Addr: "2001:db8:1:2::", Packets: 1, Bytes: 100}}},
-				Shadow:     mode.Shadow, ShadowBefore: mode.ShadowBefore}
+				JarlSets:   jarlOptions, Shadow: mode.Shadow, ShadowBefore: mode.ShadowBefore}
 			nftCheck(t, cmd, fmt.Sprintf("%s (shadow %v, before %v)", name, mode.Shadow, mode.ShadowBefore), Render(st, opt).Text)
 		}
 	}
@@ -277,3 +308,58 @@ func nftCheck(t *testing.T, cmd []string, name, text string) {
 		}
 	}
 }
+
+func TestRenderBans(t *testing.T) {
+	st := router()
+	id := map[string]int64{}
+	for _, b := range st.BanLists {
+		id[b.Name] = b.ID
+	}
+	text := Render(st, Options{Bans: banOptions(st)}).Text
+	f := func(format string, args ...any) string { return fmt.Sprintf(format, args...) }
+	r, w, e, off := id["router"], id["web"], id["edge"], id["off"]
+	for _, want := range []string{
+		f("set ban_%d_v4 { type ipv4_addr; flags timeout; }", r),
+		f("set ban_%d_v6_svc { type ipv6_addr . inet_proto . inet_service; flags timeout; }", r),
+		// The firewall: in input, every port and one port, /64 for IPv6.
+		f(`ip saddr @ban_%d_v4 counter drop comment "hc:ban%d"`, r, r),
+		f(`ip saddr . meta l4proto . th dport @ban_%d_v4_svc counter drop comment "hc:ban%d"`, r, r),
+		f(`ip6 saddr and ffff:ffff:ffff:ffff:: @ban_%d_v6 counter drop comment "hc:ban%d"`, r, r),
+		f(`ip6 saddr and ffff:ffff:ffff:ffff:: . meta l4proto . th dport @ban_%d_v6_svc counter drop comment "hc:ban%d"`, r, r),
+		// Hosts: in forward, first, to the hosts (literals and sets).
+		f(`ip daddr 10.0.10.57 ip saddr @ban_%d_v4 counter drop`, w),
+		f(`ip daddr @dns_servers_v4 ip saddr . meta l4proto . th dport @ban_%d_v4_svc counter drop`, w),
+		f(`ip6 daddr 2a02:8013:7f3d:10::57 ip6 saddr and ffff:ffff:ffff:ffff:: @ban_%d_v6 counter drop`, w),
+		// Everything: input and forward, /48.
+		f(`ip6 saddr and ffff:ffff:ffff:: @ban_%d_v6 counter drop`, e),
+		// The bans, with their time.
+		f("add element inet housecarl ban_%d_v4 { 203.0.113.9 timeout 3000s }", r),
+		f("add element inet housecarl ban_%d_v6_svc { 2001:db8:1:2:: . tcp . 22 }", w),
+		f("add element inet housecarl ban_%d_v4_svc { 198.51.100.7 . udp . 53 timeout 60s }", e),
+	} {
+		if !strings.Contains(text, want) {
+			t.Errorf("no %q in\n%s", want, text)
+		}
+	}
+	if n := strings.Count(text, f(`@ban_%d_v4 counter drop`, e)); n != 2 {
+		t.Errorf("scope everything: %d rules of every port in IPv4, want 2 (input and forward)", n)
+	}
+	if n := strings.Count(text, f(`@ban_%d_v4 counter drop`, w)); n != 2 {
+		t.Errorf("scope hosts: %d IPv4 rules of every port, want 2 (forward: the literal host and the set)", n)
+	}
+	// Ahead of the accepts: the first rules after loopback, and of forward.
+	in, _, _ := strings.Cut(text[strings.Index(text, "chain input"):], "established")
+	fw, _, _ := strings.Cut(text[strings.Index(text, "chain forward"):], "maxseg")
+	for _, part := range []string{in, fw} {
+		if strings.Contains(part, " accept comment \"hc:r") {
+			t.Errorf("a rule accepts before the bans:\n%s", part)
+		}
+	}
+	if strings.Contains(text, f("ban_%d_", off)) {
+		t.Errorf("a disabled list is rendered")
+	}
+	shadow := Render(st, Options{Shadow: true, Bans: banOptions(st)}).Text
+	if want := f(`ip saddr @ban_%d_v4 counter accept comment "hc:ban%d [would drop]"`, r, r); !strings.Contains(shadow, want) {
+		t.Errorf("shadow: no %q", want)
+	}
+}

internal/server/authn.go

@@ -102,6 +102,8 @@ func (s *Server) authenticate(r *http.Request) (*auth.Principal, *model.Session,
 		p, err := s.tokenPrincipal(r.Context(), strings.TrimSpace(tok), ip, r.UserAgent())
 		if err != nil {
 			s.limiter.fail("ip:" + ip)
+			// For Guard and fail2ban: the address first, so a name can't fake it.
+			s.log.Warn("token refused", "ip", ip, "reason", err.Error())
 			s.eng.Audit(r.Context(), &auth.Principal{IP: ip, Method: "token"}, "auth.token_failed", "", "failure", err.Error())
 			return nil, nil, &httpError{http.StatusUnauthorized, "unauthenticated", "invalid API token: " + err.Error()}
 		}
@@ -246,6 +248,8 @@ func (s *Server) login(w http.ResponseWriter, r *http.Request) error {
 		if err == nil && u.Disabled && ok {
 			reason = "account disabled"
 		}
+		// For Guard and fail2ban: the address first, so a name can't fake it.
+		s.log.Warn("login failed", "ip", ip, "user", name, "reason", reason)
 		s.eng.Audit(r.Context(), who, "auth.login_failed", "user "+name, "failure", reason)
 		return &httpError{http.StatusUnauthorized, "login_failed", "wrong username or password"}
 	}

internal/server/bans_test.go

@@ -0,0 +1,154 @@
+package server
+
+import (
+	"bytes"
+	"context"
+	"log/slog"
+	"strings"
+	"testing"
+
+	"housecarl/internal/api"
+	"housecarl/internal/model"
+	"housecarl/internal/store"
+)
+
+// TestBans: a program with a token for one ban list bans addresses: of
+// a service's ports, every port, or numbers; renewed when banned again;
+// IPv6 by /64; never the inside, the firewall's own, or the list's
+// never; times cut to the list's longest; the address's connections the
+// ban drops are closed; and lifted by ID or address.
+func TestBans(t *testing.T) {
+	e := newEnv(t)
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "wan", Interfaces: []string{"wan"}, External: true}, nil)
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil)
+	for _, b := range []model.BanList{
+		{Name: "web", Scope: model.BanScopeHosts, Hosts: []string{"10.0.10.57"}, Never: []string{"198.51.100.0/24"}, MaxTime: 3600},
+		{Name: "router", Scope: model.BanScopeFirewall},
+	} {
+		if code := e.call(e.token, "POST", "/banlists", b, nil); code != 201 {
+			t.Fatalf("ban list %s: %d", b.Name, code)
+		}
+	}
+	fc := &fakeConns{list: []api.Connection{
+		{Family: "ipv4", Protocol: "tcp", Source: "203.0.113.9", SourcePort: 40000, Destination: "217.155.8.194", DestinationPort: 2222, DNATTo: "10.0.10.57", DNATPort: 22},
+		{Family: "ipv4", Protocol: "tcp", Source: "203.0.113.9", SourcePort: 40001, Destination: "10.0.10.58", DestinationPort: 22},
+		{Family: "ipv4", Protocol: "tcp", Source: "203.0.113.9", SourcePort: 40002, Destination: "217.155.8.194", DestinationPort: 22},
+	}}
+	e.srv.SetConntrack(fc)
+	var tok api.Token
+	if code := e.call(e.token, "POST", "/me/tokens", api.TokenInput{Name: "guard", Grants: []string{"bans:write:web"}}, &tok); code != 201 {
+		t.Fatalf("token: %d", code)
+	}
+	ban := func(in api.BanInput, want int) api.BanResult {
+		t.Helper()
+		var out api.BanResult
+		var eb api.ErrorBody
+		code := e.call(tok.Secret, "POST", "/banlists/web/bans", in, &out)
+		if code != want {
+			e.call(tok.Secret, "POST", "/banlists/web/bans", in, &eb)
+			t.Errorf("ban %+v: %d, want %d (%+v)", in, code, want, eb)
+		}
+		return out
+	}
+	out := ban(api.BanInput{Address: "203.0.113.9", Ports: []byte(`"ssh"`), Time: 600, Source: "guard/ssh", Reason: "Failed password"}, 201)
+	if len(out.Bans) != 1 || out.Bans[0].Protocol != "tcp" || out.Bans[0].Port != 22 || out.Bans[0].Existing || out.Bans[0].Timeout != 600 {
+		t.Errorf("ssh ban: %+v", out)
+	}
+	if out.Closed != 1 || len(fc.closed) != 1 || fc.closed[0].DNATTo != "10.0.10.57" {
+		t.Errorf("closed %d: %+v (only the one to the list's host)", out.Closed, fc.closed)
+	}
+	if _, ok := e.fw.bans[`ban_`+itoa(out.Bans[0].ListID)+`_v4_svc 203.0.113.9 . tcp . 22`]; !ok {
+		t.Errorf("not in force: %+v", e.fw.bans)
+	}
+	if again := ban(api.BanInput{Address: "203.0.113.9", Ports: []byte(`22`), Protocol: "tcp"}, 201); len(again.Bans) != 1 || !again.Bans[0].Existing {
+		t.Errorf("banned again: %+v", again)
+	}
+	if v6 := ban(api.BanInput{Address: "2001:db8:1:2::77", Time: 99999}, 201); len(v6.Bans) != 1 || v6.Bans[0].Address != "2001:db8:1:2::/64" ||
+		v6.Bans[0].Protocol != "" || v6.Bans[0].Timeout != 3600 {
+		t.Errorf("IPv6, every port, cut to an hour: %+v", v6)
+	}
+	if n := ban(api.BanInput{Address: "::ffff:203.0.113.10", Ports: []byte(`53`)}, 201); len(n.Bans) != 2 || n.Bans[0].Address != "203.0.113.10" {
+		t.Errorf("a number without a protocol is tcp and udp: %+v", n)
+	}
+	if n := ban(api.BanInput{Address: "203.0.113.11", Protocol: "tcp", Ports: []byte(`["http", "https"]`)}, 201); len(n.Bans) != 2 {
+		t.Errorf("two services: %+v", n)
+	}
+	if n := ban(api.BanInput{Address: "203.0.113.12", Protocol: "tcp", Ports: []byte(`"0:65535"`)}, 201); len(n.Bans) != 1 || n.Bans[0].Protocol != "" {
+		t.Errorf("fail2ban's every port: %+v", n)
+	}
+	ban(api.BanInput{Address: "203.0.113.13", Ports: []byte(`"bogus"`)}, 400)
+	ban(api.BanInput{Address: "203.0.113.13", Protocol: "tcp"}, 400)
+	ban(api.BanInput{Address: "not-an-address"}, 400)
+	for _, a := range []string{"198.51.100.4", "10.0.10.99", "217.155.8.194", "127.0.0.1", "fe80::1", "192.168.5.5"} {
+		var eb api.ErrorBody
+		if code := e.call(tok.Secret, "POST", "/banlists/web/bans", api.BanInput{Address: a}, &eb); code != 422 || eb.Error.Code != "never_ban" {
+			t.Errorf("never ban %s: %d %+v", a, code, eb)
+		}
+	}
+	if code := e.call(tok.Secret, "POST", "/banlists/router/bans", api.BanInput{Address: "203.0.113.9"}, nil); code != 403 {
+		t.Errorf("another list: %d", code)
+	}
+	// The program may read its list, and only its list.
+	var bl model.BanList
+	if code := e.call(tok.Secret, "GET", "/banlists/web", nil, &bl); code != 200 || bl.V6Group() != 64 {
+		t.Errorf("reading its list: %d %+v", code, bl)
+	}
+	var lists []model.BanList
+	if e.call(tok.Secret, "GET", "/banlists", nil, &lists); len(lists) != 1 || lists[0].Name != "web" {
+		t.Errorf("lists: %+v", lists)
+	}
+	if code := e.call(tok.Secret, "GET", "/banlists/router", nil, nil); code != 403 {
+		t.Errorf("reading another list: %d", code)
+	}
+	var bans []model.Ban
+	e.call(tok.Secret, "GET", "/banlists/web/bans", nil, &bans)
+	if len(bans) != 7 || bans[0].List != "web" || bans[0].Who != "admin" || bans[0].Source != "guard/ssh" {
+		t.Errorf("bans: %d %+v", len(bans), bans)
+	}
+	var removed map[string]int
+	if code := e.call(tok.Secret, "DELETE", "/banlists/web/bans?address=2001:db8:1:2::5", nil, &removed); code != 200 || removed["removed"] != 1 {
+		t.Errorf("lift by address: %d %+v", code, removed)
+	}
+	if code := e.call(tok.Secret, "DELETE", "/banlists/web/bans/"+itoa(bans[0].ID), nil, &removed); code != 200 || removed["removed"] != 1 {
+		t.Errorf("lift by ID: %d %+v", code, removed)
+	}
+	if code := e.call(tok.Secret, "DELETE", "/banlists/web/bans?address=203.0.113.200", nil, nil); code != 404 {
+		t.Errorf("lifting what isn't banned: %d", code)
+	}
+	if _, ok := e.fw.bans[`ban_`+itoa(bans[0].ListID)+`_v4_svc 203.0.113.9 . tcp . 22`]; ok {
+		t.Errorf("still in force after lifting")
+	}
+	evs, _ := e.srv.store.ListAudit(context.Background(), store.AuditFilter{Action: "ban."})
+	if len(evs) < 10 || !strings.Contains(evs[len(evs)-1].Detail, "guard/ssh: Failed password") {
+		t.Errorf("audit: %d %+v", len(evs), evs[len(evs)-1])
+	}
+	// The list's name is what programs know it by.
+	if code := e.call(e.token, "PATCH", "/banlists/web", map[string]any{"name": "web2"}, nil); code != 409 {
+		t.Errorf("renaming a ban list: %d", code)
+	}
+	// Every apply puts the bans back; a deleted list's go.
+	if got := ActiveBans(context.Background(), e.srv.store); len(got) != 5 {
+		t.Errorf("active bans: %d", len(got))
+	}
+	if code := e.call(e.token, "DELETE", "/banlists/web", nil, nil); code != 200 {
+		t.Errorf("deleting the list: %d", code)
+	}
+	if got := ActiveBans(context.Background(), e.srv.store); len(got) != 0 {
+		t.Errorf("a deleted list's bans: %d", len(got))
+	}
+}
+
+// TestFailedLoginLogged: a failed login and a refused token are logged
+// with the address first, for Guard's and fail2ban's patterns.
+func TestFailedLoginLogged(t *testing.T) {
+	e := newEnv(t)
+	var buf bytes.Buffer
+	e.srv.log = slog.New(slog.NewTextHandler(&buf, nil))
+	e.call("", "POST", "/auth/login", api.Login{Username: `x ip=8.8.8.8`, Password: "wrong"}, nil)
+	e.call("housecarl_aaaaaaaaaaaaaaaa_bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb", "GET", "/status", nil, nil)
+	for _, want := range []string{`msg="login failed" ip=127.0.0.1 user="x ip=8.8.8.8"`, `msg="token refused" ip=127.0.0.1 reason=`} {
+		if !strings.Contains(buf.String(), want) {
+			t.Errorf("no %q in\n%s", want, buf.String())
+		}
+	}
+}

internal/server/diff_test.go

@@ -0,0 +1,139 @@
+package server
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+	"testing"
+
+	udiff "github.com/aymanbagabas/go-udiff"
+
+	"housecarl/internal/api"
+	"housecarl/internal/model"
+)
+
+// TestBlockHeaders: each hunk says which chain it is in, even when the
+// chain's own line is far above it.
+func TestBlockHeaders(t *testing.T) {
+	var b strings.Builder
+	b.WriteString("table inet housecarl {\n\tset lan_v4 { type ipv4_addr; }\n\tchain input {\n")
+	for i := 0; i < 20; i++ {
+		b.WriteString("\t\tcounter comment \"in\"\n")
+	}
+	b.WriteString("\t}\n\tchain forward {\n")
+	for i := 0; i < 20; i++ {
+		b.WriteString("\t\tcounter comment \"fw\"\n")
+	}
+	b.WriteString("\t}\n}\n")
+	now := b.String()
+	then := strings.Replace(now, "\t\tcounter comment \"in\"\n\t}", "\t\tcounter comment \"in\"\n\t\taccept comment \"new in\"\n\t}", 1)
+	then = strings.Replace(then, "\t\tcounter comment \"fw\"\n\t}", "\t\taccept comment \"new fw\"\n\t}", 1)
+
+	diff := blockHeaders(udiff.Unified("a", "b", now, then), now, then)
+	var heads []string
+	for _, l := range strings.Split(diff, "\n") {
+		if strings.HasPrefix(l, "@@") {
+			heads = append(heads, l)
+		}
+	}
+	if len(heads) != 2 || !strings.HasSuffix(heads[0], "@@ chain input") || !strings.HasSuffix(heads[1], "@@ chain forward") {
+		t.Fatalf("hunk headers %q, want chain input then chain forward\n%s", heads, diff)
+	}
+	if blockHeaders("", now, then) != "" {
+		t.Fatal("no diff should stay empty")
+	}
+}
+
+// TestHistoryDiff: an entry's diff is its own change, rebuilt from the
+// current configuration however many entries came after it.
+func TestHistoryDiff(t *testing.T) {
+	e := newEnv(t)
+	var mr api.MutationResponse
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil)
+	e.call(e.token, "POST", "/rules", model.Rule{Chain: "input", Match: model.Match{Services: []string{"ssh"}}, Comment: "first"}, &mr)
+	first := mr.HistoryID
+	e.call(e.token, "POST", "/rules", model.Rule{Chain: "forward", Match: model.Match{Services: []string{"http"}}, Comment: "second"}, nil)
+	e.call(e.token, "PATCH", "/settings", map[string]any{"builtins": map[string]any{"drop_invalid": true}}, nil)
+
+	var out struct{ Diff string }
+	if code := e.call(e.token, "GET", "/history/"+itoa(first)+"/diff", nil, &out); code != 200 {
+		t.Fatalf("diff: %d", code)
+	}
+	var added []string
+	for _, l := range strings.Split(out.Diff, "\n") {
+		if strings.HasPrefix(l, "+") && !strings.HasPrefix(l, "+++") {
+			added = append(added, l)
+		}
+	}
+	if len(added) == 0 || !strings.Contains(strings.Join(added, "\n"), ` first"`) || strings.Contains(out.Diff, ` second"`) || !strings.Contains(out.Diff, "@@ chain input") {
+		t.Errorf("entry %d's diff:\n%s", first, out.Diff)
+	}
+	if code := e.call(e.token, "GET", "/history/9999/diff", nil, nil); code != 404 {
+		t.Errorf("unknown entry: %d", code)
+	}
+}
+
+// TestHunkStarts: after a hunk with unchanged lines between its edits (a
+// moved line), the later hunks' new sides start where they do.
+func TestHunkStarts(t *testing.T) {
+	var a, b strings.Builder
+	for i := 1; i <= 20; i++ {
+		fmt.Fprintf(&a, "%d\n", i)
+		switch i {
+		case 4:
+		case 6:
+			b.WriteString("6\n4\n")
+		case 14:
+		default:
+			fmt.Fprintf(&b, "%d\n", i)
+		}
+	}
+	diff := hunkStarts(udiff.Unified("a", "b", a.String(), b.String()))
+	var heads []string
+	for _, l := range strings.Split(diff, "\n") {
+		if strings.HasPrefix(l, "@@") {
+			heads = append(heads, l)
+		}
+	}
+	// diff -u: the move nets nothing, the deleted 14 one line.
+	if want := []string{"@@ -1,9 +1,9 @@", "@@ -11,7 +11,6 @@"}; strings.Join(heads, "|") != strings.Join(want, "|") {
+		t.Fatalf("hunk headers %q, want %q\n%s", heads, want, diff)
+	}
+}
+
+// TestHistoryDiffUpdate: an update's diff is only what it changed; the
+// object stepped back to its old form stays where it was.
+func TestHistoryDiffUpdate(t *testing.T) {
+	e := newEnv(t)
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil)
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "wan", Interfaces: []string{"wan"}, External: true}, nil)
+	var ids []int64
+	for i, port := range []string{"8096", "443", "50300", "7777", "25"} {
+		var mr api.MutationResponse
+		e.call(e.token, "POST", "/forwards", map[string]any{"name": "f" + port, "ports": port, "to": fmt.Sprintf("10.0.10.%d", 30+i),
+			"public_addresses": []string{"203.0.113.1"}, "hairpin": true}, &mr)
+		var f model.PortForward
+		if err := json.Unmarshal(mr.Object, &f); err != nil {
+			t.Fatal(err)
+		}
+		ids = append(ids, f.ID)
+	}
+	var mr api.MutationResponse
+	if code := e.call(e.token, "PATCH", "/forwards/"+itoa(ids[2]), map[string]any{"hairpin": false}, &mr); code != 200 {
+		t.Fatalf("update: %d", code)
+	}
+	var out struct{ Diff string }
+	if code := e.call(e.token, "GET", "/history/"+itoa(mr.HistoryID)+"/diff", nil, &out); code != 200 {
+		t.Fatalf("diff: %d", code)
+	}
+	var changed []string
+	for _, l := range strings.Split(out.Diff, "\n") {
+		if (strings.HasPrefix(l, "+") || strings.HasPrefix(l, "-")) && !strings.HasPrefix(l, "+++") && !strings.HasPrefix(l, "---") {
+			changed = append(changed, l)
+		}
+	}
+	if len(changed) != 1 || !strings.HasPrefix(changed[0], "-") || !strings.Contains(changed[0], "-hairpin") ||
+		!strings.Contains(out.Diff, "(before "+itoa(mr.HistoryID)+")") || !strings.Contains(out.Diff, "@@ chain srcnat") {
+		t.Errorf("entry %d's diff, want only the hairpin line gone, in chain srcnat:\n%s", mr.HistoryID, out.Diff)
+	}
+}

internal/server/h_bans.go

@@ -0,0 +1,555 @@
+package server
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/netip"
+	"strconv"
+	"strings"
+	"time"
+
+	"housecarl/internal/api"
+	"housecarl/internal/auth"
+	"housecarl/internal/model"
+	"housecarl/internal/render"
+	"housecarl/internal/store"
+)
+
+// Ban lists (docs/bans.md): the lists are configuration objects; their
+// bans are kept apart, like a dynamic set's entries, audited but not in
+// the history or on probation. A ban is saved first, then put in force;
+// every apply puts all of them back (ActiveBans).
+
+// banList finds a ban list the principal may read or ban into.
+func (s *Server) banList(r *http.Request, p *auth.Principal, write bool) (*model.BanList, error) {
+	ref := r.PathValue("ref")
+	o := s.eng.State().Find(model.KindBanList, ref)
+	if o == nil {
+		if !p.CanBan(ref, write) {
+			return nil, banForbidden(ref, write)
+		}
+		return nil, notFound("no ban list %s", ref)
+	}
+	b := o.(*model.BanList)
+	if !p.CanBan(b.Name, write) {
+		return nil, banForbidden(b.Name, write)
+	}
+	return b, nil
+}
+
+func banForbidden(list string, write bool) error {
+	access := "read"
+	if write {
+		access = "write"
+	}
+	return forbidden("permission denied: this needs bans:%s for %s", access, list)
+}
+
+// ActiveBans are the bans to put back with every apply (nft.Firewall's
+// Bans).
+func ActiveBans(ctx context.Context, st *store.Store) []render.Ban {
+	list, err := st.ListBans(ctx, 0)
+	if err != nil {
+		return nil
+	}
+	out := make([]render.Ban, 0, len(list))
+	for _, b := range list {
+		if rb, ok := renderBan(b); ok {
+			out = append(out, rb)
+		}
+	}
+	return out
+}
+
+func renderBan(b *model.Ban) (render.Ban, bool) {
+	p, err := b.Prefix()
+	if err != nil {
+		return render.Ban{}, false
+	}
+	return render.Ban{List: b.ListID, Addr: p, Proto: b.Protocol, Port: b.Port, Timeout: b.Timeout}, true
+}
+
+// listBans answers GET /banlists/{ref}/bans, and GET /bans: every list's
+// the principal may read.
+func (s *Server) listBans(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st := s.eng.State()
+	var id int64
+	if r.PathValue("ref") != "" {
+		b, err := s.banList(r, p, false)
+		if err != nil {
+			return err
+		}
+		id = b.ID
+	}
+	all, err := s.store.ListBans(r.Context(), id)
+	if err != nil {
+		return err
+	}
+	out := []*model.Ban{}
+	for _, b := range all {
+		o := st.ByID(model.KindBanList, b.ListID)
+		if o == nil || !p.CanBan(o.Label(), false) {
+			continue
+		}
+		b.List = o.Label()
+		out = append(out, b)
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
+// addBan answers POST /banlists/{ref}/bans.
+func (s *Server) addBan(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	list, err := s.banList(r, p, true)
+	if err != nil {
+		return err
+	}
+	var in api.BanInput
+	if err := decodeJSON(r, &in); err != nil {
+		return err
+	}
+	st := s.eng.State()
+	if list.Disabled {
+		return conflict("ban list %s is disabled: enable it first", list.Name)
+	}
+	addr, err := netip.ParseAddr(strings.Trim(strings.TrimSpace(in.Address), "[]"))
+	if err != nil {
+		return badRequest("%q isn't an address", in.Address)
+	}
+	addr = addr.Unmap().WithZone("")
+	bits := 32
+	if addr.Is6() {
+		bits = list.V6Group()
+	}
+	prefix := netip.PrefixFrom(addr, bits).Masked()
+	if why := s.neverBan(r.Context(), st, list, p, addr, prefix); why != "" {
+		s.eng.Audit(r.Context(), p, "ban.add", list.Name+" "+model.BanAddress(prefix), "failure", why)
+		return &httpError{http.StatusUnprocessableEntity, "never_ban", fmt.Sprintf("%s isn't banned: %s", model.BanAddress(prefix), why)}
+	}
+	ports, err := banPorts(st, in.Protocol, in.Ports)
+	if err != nil {
+		return badRequest("%v", err)
+	}
+	var expires *time.Time
+	switch secs := banSeconds(list, in.Time); {
+	case secs > 0:
+		t := s.nowFn().Add(time.Duration(secs) * time.Second)
+		expires = &t
+	}
+	if n, err := s.store.CountBans(r.Context(), list.ID); err != nil {
+		return err
+	} else if n+len(ports) > list.Entries() {
+		existing := 0
+		for _, pp := range ports {
+			if s.banExists(r.Context(), list.ID, model.BanAddress(prefix), pp) {
+				existing++
+			}
+		}
+		if n+len(ports)-existing > list.Entries() {
+			return &httpError{http.StatusUnprocessableEntity, "list_full", fmt.Sprintf("ban list %s holds its most bans (%d, max_entries); wait for some to end, or raise it", list.Name, list.Entries())}
+		}
+	}
+	out := api.BanResult{Bans: []api.BanMade{}}
+	for _, pp := range ports {
+		b := &model.Ban{ListID: list.ID, List: list.Name, Address: model.BanAddress(prefix), Protocol: pp.proto, Port: pp.port,
+			Expires: expires, Who: p.Name(), Source: clip(in.Source, 100), Reason: clip(in.Reason, 500)}
+		existing, err := s.store.PutBan(r.Context(), b)
+		if err != nil {
+			return err
+		}
+		if expires != nil {
+			b.Timeout = int(time.Until(*expires).Round(time.Second) / time.Second)
+		}
+		rb, _ := renderBan(b)
+		if err := s.fw.AddBan(r.Context(), rb); err != nil {
+			s.log.Warn("putting a ban in force failed; the next change or restart adds it", "list", list.Name, "address", b.Address, "err", err)
+		}
+		out.Bans = append(out.Bans, api.BanMade{Ban: *b, Existing: existing})
+		detail := b.Source
+		if b.Reason != "" {
+			detail = strings.TrimSpace(detail + ": " + b.Reason)
+		}
+		s.eng.Audit(r.Context(), p, "ban.add", list.Name+" "+banLabel(b), "success", detail)
+	}
+	out.Closed = s.closeBanned(r.Context(), st, list, prefix, ports)
+	writeJSON(w, http.StatusCreated, out)
+	return nil
+}
+
+func (s *Server) banExists(ctx context.Context, list int64, addr string, pp banPort) bool {
+	bans, _ := s.store.ListBans(ctx, list)
+	for _, b := range bans {
+		if b.Address == addr && b.Protocol == pp.proto && b.Port == pp.port {
+			return true
+		}
+	}
+	return false
+}
+
+// banSeconds is a ban's length: what was asked (0 the list's default, -1
+// its longest), cut to the list's longest. 0 means it doesn't end.
+func banSeconds(list *model.BanList, asked int) int {
+	max := list.BanMaxTime()
+	secs := asked
+	switch {
+	case asked == 0:
+		secs = list.BanTime()
+	case asked < 0:
+		secs = max
+	}
+	if max > 0 && secs > max {
+		secs = max
+	}
+	return secs
+}
+
+func banLabel(b *model.Ban) string {
+	if b.Protocol == "" {
+		return b.Address
+	}
+	return fmt.Sprintf("%s %s/%d", b.Address, b.Protocol, b.Port)
+}
+
+func clip(s string, n int) string {
+	s = strings.TrimSpace(s)
+	if len(s) > n {
+		return s[:n]
+	}
+	return s
+}
+
+// banPort is one protocol and port banned; proto "" is every port.
+type banPort struct {
+	proto string
+	port  int
+}
+
+// maxBanPorts is the most ports one ban request may name: a range in a
+// service counts each port.
+const maxBanPorts = 64
+
+// banPorts reads a ban request's protocol and ports (api.BanInput).
+func banPorts(st *model.State, protocol string, raw json.RawMessage) ([]banPort, error) {
+	protocol = strings.ToLower(strings.TrimSpace(protocol))
+	if protocol != "" && protocol != "tcp" && protocol != "udp" && protocol != "all" {
+		return nil, fmt.Errorf("protocol %q: use tcp, udp, or leave it out for every port", protocol)
+	}
+	if protocol == "all" {
+		protocol = ""
+	}
+	var words []string
+	if len(raw) > 0 && string(raw) != "null" {
+		var list []json.RawMessage
+		if json.Unmarshal(raw, &list) != nil {
+			list = []json.RawMessage{raw}
+		}
+		for _, item := range list {
+			var n int
+			var str string
+			switch {
+			case json.Unmarshal(item, &n) == nil:
+				words = append(words, strconv.Itoa(n))
+			case json.Unmarshal(item, &str) == nil:
+				words = append(words, strings.FieldsFunc(str, func(c rune) bool { return c == ',' || c == ' ' })...)
+			default:
+				return nil, fmt.Errorf("ports: give numbers or service names, in a list or a string")
+			}
+		}
+	}
+	if len(words) == 0 {
+		if protocol != "" {
+			return nil, fmt.Errorf("protocol %s without ports: give the ports, or leave the protocol out for every port", protocol)
+		}
+		return []banPort{{}}, nil
+	}
+	protos := []string{"tcp", "udp"}
+	if protocol != "" {
+		protos = []string{protocol}
+	}
+	var out []banPort
+	seen := map[banPort]bool{}
+	add := func(proto string, port int) {
+		bp := banPort{proto, port}
+		if !seen[bp] {
+			seen[bp] = true
+			out = append(out, bp)
+		}
+	}
+	for _, w := range words {
+		lw := strings.ToLower(w)
+		switch lw {
+		case "all", "any", "0:65535", "1:65535", "0-65535", "1-65535":
+			return []banPort{{}}, nil
+		}
+		if n, err := strconv.Atoi(w); err == nil {
+			if n < 1 || n > 65535 {
+				return nil, fmt.Errorf("port %d: use 1 to 65535", n)
+			}
+			for _, p := range protos {
+				add(p, n)
+			}
+			continue
+		}
+		svc := st.Service(w)
+		if svc == nil {
+			return nil, fmt.Errorf("%q is neither a port nor a service (built-in or yours)", w)
+		}
+		matched := false
+		for _, e := range st.ServiceEntries([]string{svc.Name}) {
+			if e.Proto != "tcp" && e.Proto != "udp" || protocol != "" && e.Proto != protocol {
+				continue
+			}
+			for _, part := range strings.Split(e.Ports, ",") {
+				lo, hi, _ := strings.Cut(strings.TrimSpace(part), "-")
+				a, err1 := strconv.Atoi(lo)
+				b := a
+				var err2 error
+				if hi != "" {
+					b, err2 = strconv.Atoi(hi)
+				}
+				if err1 != nil || err2 != nil || b-a >= maxBanPorts {
+					return nil, fmt.Errorf("service %s has the range %s: ban every port instead", svc.Name, part)
+				}
+				for port := a; port <= b; port++ {
+					add(e.Proto, port)
+					matched = true
+				}
+			}
+		}
+		if !matched {
+			return nil, fmt.Errorf("service %s has no %s ports", svc.Name, map[bool]string{true: protocol, false: "tcp or udp"}[protocol != ""])
+		}
+	}
+	if len(out) > maxBanPorts {
+		return nil, fmt.Errorf("%d ports in one ban: ban every port instead (up to %d)", len(out), maxBanPorts)
+	}
+	return out, nil
+}
+
+// neverBan says why an address (banned as prefix) must not be banned, or
+// "": it is the firewall's, an inside network's, the client's own, in the
+// list's never, or not an address one bans.
+func (s *Server) neverBan(ctx context.Context, st *model.State, list *model.BanList, p *auth.Principal, addr netip.Addr, prefix netip.Prefix) string {
+	switch {
+	case addr.IsLoopback(), addr.IsUnspecified(), addr.IsMulticast(), addr.IsLinkLocalUnicast(), addr.IsLinkLocalMulticast():
+		return "it is a loopback, link-local, multicast or unspecified address"
+	}
+	if own, err := netip.ParseAddr(p.IP); err == nil && prefix.Contains(own.Unmap()) {
+		return "it is the address of whoever asked (" + own.Unmap().String() + ")"
+	}
+	inside := s.insideNetworks(st)
+	if inside(addr) || inside(prefix.Addr()) {
+		return "it is inside: in a network of an inside zone, or private"
+	}
+	external := map[string]bool{}
+	for _, z := range st.Zones {
+		external[z.Name] = z.External
+	}
+	for net, zone := range s.connected(st) {
+		if !external[zone] && net.Overlaps(prefix) {
+			return fmt.Sprintf("it overlaps %s, a network of zone %s", net, zone)
+		}
+	}
+	if s.ifaces != nil {
+		if all, err := s.ifaces.All(); err == nil {
+			for name, ps := range all {
+				for _, a := range ps {
+					if prefix.Contains(a.Addr()) {
+						return fmt.Sprintf("it is the firewall's own (%s on %s)", a.Addr(), name)
+					}
+				}
+			}
+		}
+	}
+	for _, o := range st.Settings.OwnPrefixes {
+		if op, err := netip.ParsePrefix(o); err == nil && op.Overlaps(prefix) {
+			return "it is in the firewall's own prefix " + o + " (settings)"
+		}
+	}
+	for _, ref := range list.Never {
+		if why := s.inNever(ctx, st, ref, prefix); why != "" {
+			return why + " (the list's never)"
+		}
+	}
+	return ""
+}
+
+// inNever: is prefix in a never entry (an address, or a set)?
+func (s *Server) inNever(ctx context.Context, st *model.State, ref string, prefix netip.Prefix) string {
+	overlaps := func(entry string) bool {
+		a, err := model.ParseAddress(entry)
+		return err == nil && a.Overlaps(prefix)
+	}
+	if model.IsLiteral(ref) {
+		if overlaps(ref) {
+			return "it is in " + ref
+		}
+		return ""
+	}
+	set := st.Set(ref)
+	if set == nil {
+		return ""
+	}
+	entries := set.Entries
+	if set.Runtime() {
+		if t, err := s.fw.Table(ctx); err == nil {
+			for _, e := range t.Elements[set.Name] {
+				entries = append(entries, e.Addr)
+			}
+		}
+	}
+	for _, e := range entries {
+		if overlaps(e) {
+			return fmt.Sprintf("it is in set %s (%s)", set.Name, e)
+		}
+	}
+	return ""
+}
+
+// closeBanned closes the banned address's connections the list's bans
+// now drop: offloaded to the flowtable, they would go on without
+// reaching the rules. Not in shadow mode, which changes no traffic.
+func (s *Server) closeBanned(ctx context.Context, st *model.State, list *model.BanList, prefix netip.Prefix, ports []banPort) int {
+	if s.cfg.Shadow || s.conns == nil {
+		return 0
+	}
+	conns, err := s.conns.List(ctx)
+	if err != nil {
+		s.log.Warn("listing connections to close a ban's failed", "err", err)
+		return 0
+	}
+	own := map[netip.Addr]bool{}
+	if s.ifaces != nil {
+		if all, err := s.ifaces.All(); err == nil {
+			for _, ps := range all {
+				for _, a := range ps {
+					own[a.Addr()] = true
+				}
+			}
+		}
+	}
+	h4, h6 := st.SplitRefs(list.Hosts)
+	hosts := append(append([]string{}, h4.Literals...), h6.Literals...)
+	for _, name := range append(h4.Sets, h6.Sets...) {
+		if set := st.Set(name); set != nil {
+			hosts = append(hosts, set.Entries...)
+		}
+	}
+	isHost := func(a netip.Addr) bool {
+		for _, h := range hosts {
+			if x, err := model.ParseAddress(h); err == nil && x.Contains(a) {
+				return true
+			}
+		}
+		return false
+	}
+	closed := 0
+	for _, c := range conns {
+		src, err := netip.ParseAddr(c.Source)
+		if err != nil || !prefix.Contains(src.Unmap()) {
+			continue
+		}
+		dst, _ := netip.ParseAddr(c.Destination)
+		port := c.DestinationPort
+		if c.DNATTo != "" {
+			dst, _ = netip.ParseAddr(c.DNATTo)
+			if c.DNATPort != 0 {
+				port = c.DNATPort
+			}
+		}
+		toFirewall := own[dst.Unmap()]
+		switch list.Scope {
+		case model.BanScopeFirewall:
+			if !toFirewall {
+				continue
+			}
+		case model.BanScopeHosts:
+			if toFirewall || !isHost(dst.Unmap()) {
+				continue
+			}
+		}
+		hit := false
+		for _, pp := range ports {
+			hit = hit || pp.proto == "" || pp.proto == c.Protocol && pp.port == port
+		}
+		if !hit {
+			continue
+		}
+		if err := s.conns.Close(ctx, c); err == nil {
+			closed++
+		}
+	}
+	return closed
+}
+
+// deleteBans answers DELETE /banlists/{ref}/bans/{id}, and DELETE
+// /banlists/{ref}/bans?address=A: every ban of that address (any of its
+// grouping), of every port and of each.
+func (s *Server) deleteBans(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	list, err := s.banList(r, p, true)
+	if err != nil {
+		return err
+	}
+	var gone []*model.Ban
+	if idText := r.PathValue("id"); idText != "" {
+		id, err := strconv.ParseInt(idText, 10, 64)
+		if err != nil {
+			return badRequest("ban ID %q isn't a number", idText)
+		}
+		b, err := s.store.GetBan(r.Context(), id)
+		if errors.Is(err, store.ErrNotFound) || err == nil && b.ListID != list.ID {
+			return notFound("no ban %d in ban list %s", id, list.Name)
+		}
+		if err != nil {
+			return err
+		}
+		gone = append(gone, b)
+	} else {
+		q := strings.Trim(strings.TrimSpace(r.URL.Query().Get("address")), "[]")
+		a, err := netip.ParseAddr(q)
+		if err != nil {
+			return badRequest("say which ban: DELETE …/bans/ID, or …/bans?address=ADDRESS")
+		}
+		a = a.Unmap()
+		bans, err := s.store.ListBans(r.Context(), list.ID)
+		if err != nil {
+			return err
+		}
+		for _, b := range bans {
+			if pre, err := b.Prefix(); err == nil && pre.Contains(a) {
+				gone = append(gone, b)
+			}
+		}
+		if len(gone) == 0 {
+			return notFound("%s isn't banned in ban list %s", a, list.Name)
+		}
+	}
+	for _, b := range gone {
+		if err := s.store.DeleteBan(r.Context(), b.ID); err != nil {
+			return err
+		}
+		if rb, ok := renderBan(b); ok {
+			if err := s.fw.DeleteBan(r.Context(), rb); err != nil {
+				s.log.Warn("lifting a ban failed; the next change or restart drops it", "list", list.Name, "address", b.Address, "err", err)
+			}
+		}
+		s.eng.Audit(r.Context(), p, "ban.remove", list.Name+" "+banLabel(b), "success", "")
+	}
+	writeJSON(w, http.StatusOK, map[string]int{"removed": len(gone)})
+	return nil
+}
+
+// pruneBans forgets the bans that ended, and those of lists st no longer
+// has.
+func (s *Server) pruneBans(ctx context.Context, st *model.State) {
+	var ids []int64
+	for _, b := range st.BanLists {
+		ids = append(ids, b.ID)
+	}
+	if _, err := s.store.PruneBans(ctx, ids); err != nil {
+		s.log.Warn("pruning bans failed", "err", err)
+	}
+}

internal/server/h_changesets.go

@@ -89,6 +89,17 @@ func (s *Server) stage(w http.ResponseWriter, r *http.Request, p *auth.Principal
 	if err := replay(before, cs.Ops); err != nil {
 		return conflict("changeset %d can't be applied as it is (%v); review it first", id, err)
 	}
+	// A move right after a move of the same object takes its place:
+	// moving a rule up three steps is one operation.
+	kept := cs.Ops
+	if n := len(kept); n > 0 && foldMove(before, &kept[n-1], &op) {
+		kept = kept[:n-1]
+		before = s.eng.State()
+		if err := replay(before, kept); err != nil {
+			return conflict("changeset %d can't be applied as it is (%v); review it first", id, err)
+		}
+	}
+	folded := len(kept) < len(cs.Ops)
 	after := before.Clone()
 	objID, err := applyOp(after, &op)
 	if err != nil {
@@ -98,6 +109,13 @@ func (s *Server) stage(w http.ResponseWriter, r *http.Request, p *auth.Principal
 	after.Sort()
 	changes := engine.Diff(before, after)
 	if len(changes) == 0 {
+		// Moved back where it was: the earlier move goes too.
+		if folded && !queryBool(r, "dry_run") {
+			cs.Ops = kept
+			if err := s.store.UpdateChangeset(r.Context(), cs); err != nil {
+				return err
+			}
+		}
 		writeJSON(w, http.StatusOK, api.MutationResponse{Changes: []model.Change{}, Changeset: cs})
 		return nil
 	}
@@ -108,7 +126,7 @@ func (s *Server) stage(w http.ResponseWriter, r *http.Request, p *auth.Principal
 		op.Summary = engine.UndoDescription(&h)
 	}
 	op.AddedAt = s.nowFn()
-	for _, o := range cs.Ops {
+	for _, o := range kept {
 		if o.Seq >= op.Seq {
 			op.Seq = o.Seq + 1
 		}
@@ -116,7 +134,7 @@ func (s *Server) stage(w http.ResponseWriter, r *http.Request, p *auth.Principal
 	if op.Seq == 0 {
 		op.Seq = 1
 	}
-	ops := append(append([]model.Op{}, cs.Ops...), op)
+	ops := append(append([]model.Op{}, kept...), op)
 	dry := queryBool(r, "dry_run")
 	// The whole changeset, checked as it would be applied.
 	res, err := s.eng.Apply(r.Context(), p, "", engine.Options{DryRun: true, Via: via(r, p)}, func(st *model.State, _ func() int64) error {
@@ -145,6 +163,31 @@ func (s *Server) stage(w http.ResponseWriter, r *http.Request, p *auth.Principal
 	return nil
 }
 
+// foldMove reports whether op, a move, can take the place of prev, the
+// changeset's last operation: a move of the same object. A move puts
+// the object relative to the others, which an earlier move of it
+// doesn't change, so only the chain it moved to has to be carried over.
+// st is the changeset so far.
+func foldMove(st *model.State, prev, op *model.Op) bool {
+	if prev.Op != model.OpMove || op.Op != model.OpMove || prev.Kind != op.Kind {
+		return false
+	}
+	a, err1 := findObject(st, prev.Kind, prev.Ref)
+	b, err2 := findObject(st, op.Kind, op.Ref)
+	if err1 != nil || err2 != nil || a.GetID() != b.GetID() {
+		return false
+	}
+	var was, now api.MoveInput
+	if json.Unmarshal(prev.Data, &was) != nil || json.Unmarshal(op.Data, &now) != nil {
+		return false
+	}
+	if now.Chain == "" && was.Chain != "" {
+		now.Chain = was.Chain
+		op.Data, _ = json.Marshal(now)
+	}
+	return true
+}
+
 func (s *Server) createChangeset(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
 	if err := require(p, auth.ResConfig, true); err != nil {
 		return err

internal/server/h_config.go

@@ -3,6 +3,7 @@ package server
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 	"net/http"
 	"net/netip"
 	"sort"
@@ -98,16 +99,138 @@ func (s *Server) respondChange(w http.ResponseWriter, r *http.Request, p *auth.P
 // rulesetDiff is the unified diff of the rulesets two configurations
 // make: the file housecarl-ruleset.service loads, now and after.
 func (s *Server) rulesetDiff(before, after *model.State) string {
+	return s.labeledDiff(before, after, "now", "after")
+}
+
+// labeledDiff is rulesetDiff with its own names for the two sides.
+func (s *Server) labeledDiff(before, after *model.State, from, to string) string {
 	if before == nil || after == nil {
 		return ""
 	}
-	return udiff.Unified("ruleset.nft (now)", "ruleset.nft (after)", s.fw.Render(before).Text, s.fw.Render(after).Text)
+	now, then := s.fw.Render(before).Text, s.fw.Render(after).Text
+	diff := hunkStarts(udiff.Unified("ruleset.nft ("+from+")", "ruleset.nft ("+to+")", now, then))
+	return blockHeaders(diff, now, then)
+}
+
+// hunkStarts numbers each hunk's new side again, from its old side and
+// the lines the hunks before it added and removed. go-udiff (v0.4.1)
+// leaves out of its count the unchanged lines between two edits of one
+// hunk, so after a hunk like a moved line every later one started too
+// early ("@@ -76,9 +74,9 @@" for "+76,9"), and blockHeaders named the
+// chain before it.
+func hunkStarts(diff string) string {
+	lines := strings.SplitAfter(diff, "\n")
+	delta := 0
+	for i := 0; i < len(lines); i++ {
+		f := strings.Fields(lines[i])
+		if !strings.HasPrefix(lines[i], "@@ ") || len(f) < 4 || f[3] != "@@" {
+			continue
+		}
+		start, _, _ := strings.Cut(f[1][1:], ",")
+		from, err := strconv.Atoi(start)
+		if err != nil {
+			continue
+		}
+		oldN, newN := 0, 0
+		for _, l := range lines[i+1:] {
+			if strings.HasPrefix(l, "@@ ") {
+				break
+			}
+			switch {
+			case strings.HasPrefix(l, "-"):
+				oldN++
+			case strings.HasPrefix(l, "+"):
+				newN++
+			case strings.HasPrefix(l, " "):
+				oldN++
+				newN++
+			}
+		}
+		// An empty side is numbered by the line before it.
+		first := from
+		if oldN == 0 {
+			first++
+		}
+		to := first + delta
+		if newN == 0 {
+			to--
+		}
+		side := "+" + strconv.Itoa(to)
+		if newN > 1 {
+			side += "," + strconv.Itoa(newN)
+		}
+		f[2] = side
+		lines[i] = strings.Join(f, " ") + "\n"
+		delta += newN - oldN
+	}
+	return strings.Join(lines, "")
+}
+
+// blockHeaders names, after each hunk's @@ line, the chain (or other
+// block of the table) the hunk starts in, as git names the function:
+// "@@ -40,6 +40,8 @@ chain forward". Without it a change deep in a long
+// chain doesn't say which chain it is in.
+func blockHeaders(diff, now, then string) string {
+	if diff == "" {
+		return diff
+	}
+	oldBlocks, newBlocks := enclosingBlocks(now), enclosingBlocks(then)
+	lines := strings.SplitAfter(diff, "\n")
+	for i, l := range lines {
+		if !strings.HasPrefix(l, "@@ ") {
+			continue
+		}
+		// "@@ -a,b +c,d @@": the new side's start, or the old side's
+		// when nothing of the hunk is left.
+		f := strings.Fields(l)
+		if len(f) < 4 || f[3] != "@@" {
+			continue
+		}
+		block := blockAt(newBlocks, f[2])
+		if block == "" {
+			block = blockAt(oldBlocks, f[1])
+		}
+		if block != "" {
+			lines[i] = strings.TrimRight(l, "\n") + " " + block + "\n"
+		}
+	}
+	return strings.Join(lines, "")
+}
+
+// enclosingBlocks gives each line of a rendered ruleset the block of the
+// table it is in ("chain input"), "" outside one. A block opens with a
+// line of one tab ending in "{" and closes with "\t}".
+func enclosingBlocks(text string) []string {
+	var out []string
+	cur := ""
+	for _, l := range strings.Split(text, "\n") {
+		if strings.HasPrefix(l, "\t") && !strings.HasPrefix(l, "\t\t") && strings.HasSuffix(l, "{") {
+			cur = strings.TrimSpace(strings.TrimSuffix(l, "{"))
+		}
+		out = append(out, cur)
+		if l == "\t}" {
+			cur = ""
+		}
+	}
+	return out
+}
+
+// blockAt is the block at a hunk side's start ("+40,8" or "-40"); lines
+// count from 1, and an empty side (",0") sits after its line.
+func blockAt(blocks []string, side string) string {
+	start, _, _ := strings.Cut(side[1:], ",")
+	n, err := strconv.Atoi(start)
+	if err != nil || n < 1 || n > len(blocks) {
+		return ""
+	}
+	return blocks[n-1]
 }
 
 // kindOf maps the API's plural path names to kinds.
 var kindOf = map[string]string{
 	"zones": model.KindZone, "sets": model.KindSet, "services": model.KindService, "rules": model.KindRule,
 	"forwards": model.KindForward, "snats": model.KindSNAT, "redirects": model.KindRedirect,
+	"banlists": model.KindBanList,
 }
 
 func pathKind(r *http.Request) (string, error) {
@@ -128,13 +251,16 @@ func findObject(st *model.State, kind, ref string) (model.Object, error) {
 // ---- objects
 
 func (s *Server) listObjects(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
-	if err := require(p, auth.ResConfig, false); err != nil {
-		return err
-	}
 	kind, err := pathKind(r)
 	if err != nil {
 		return err
 	}
+	if kind == model.KindBanList && !p.Can(auth.ResConfig, false) {
+		return s.listOwnBanLists(w, p)
+	}
+	if err := require(p, auth.ResConfig, false); err != nil {
+		return err
+	}
 	cur, st, draft, err := s.viewState(w, r)
 	if err != nil {
 		return err
@@ -180,13 +306,22 @@ func (s *Server) listObjects(w http.ResponseWriter, r *http.Request, p *auth.Pri
 }
 
 func (s *Server) getObject(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
-	if err := require(p, auth.ResConfig, false); err != nil {
-		return err
-	}
 	kind, err := pathKind(r)
 	if err != nil {
 		return err
 	}
+	// A program that bans into a list may read it (its grouping, times).
+	if kind == model.KindBanList && !p.Can(auth.ResConfig, false) {
+		b, err := s.banList(r, p, false)
+		if err != nil {
+			return err
+		}
+		writeJSON(w, http.StatusOK, b)
+		return nil
+	}
+	if err := require(p, auth.ResConfig, false); err != nil {
+		return err
+	}
 	_, st, _, err := s.viewState(w, r)
 	if err != nil {
 		return err
@@ -223,6 +358,8 @@ func decodeObject(kind string, data []byte) (model.Object, error) {
 		o = &model.SourceNAT{}
 	case model.KindRedirect:
 		o = &model.Redirect{}
+	case model.KindBanList:
+		o = &model.BanList{}
 	}
 	dec := json.NewDecoder(strings.NewReader(string(data)))
 	dec.DisallowUnknownFields()
@@ -274,6 +411,8 @@ func setID(o model.Object, id int64) {
 		x.ID = id
 	case *model.Redirect:
 		x.ID = id
+	case *model.BanList:
+		x.ID = id
 	}
 }
 
@@ -391,6 +530,11 @@ func usedBy(st *model.State, kind string, o model.Object) string {
 				return f.Label()
 			}
 		}
+		for _, b := range st.BanLists {
+			if has(b.Hosts) || has(b.Never) {
+				return "ban list " + b.Name
+			}
+		}
 	}
 	return ""
 }
@@ -433,6 +577,10 @@ func renameRefs(st *model.State, kind, old, now string) {
 			fix(f.PublicAddresses)
 			fix(f.HairpinSources)
 		}
+		for _, b := range st.BanLists {
+			fix(b.Hosts)
+			fix(b.Never)
+		}
 	}
 }
 
@@ -520,6 +668,10 @@ func matrixHits(m *api.Matrix, counters map[string]nft.Counter) {
 
 // connected maps the networks on the firewall's interfaces (link-local
 // and loopback aside) to their zones.
+// Connected are the networks connected to the firewall's interfaces,
+// with their zones (link-local and loopback left out).
+func (s *Server) Connected(st *model.State) map[netip.Prefix]string { return s.connected(st) }
+
 func (s *Server) connected(st *model.State) map[netip.Prefix]string {
 	out := map[netip.Prefix]string{}
 	for _, i := range s.hostInterfaces(st) {
@@ -590,6 +742,39 @@ func (s *Server) getHistory(w http.ResponseWriter, r *http.Request, p *auth.Prin
 	return nil
 }
 
+// historyDiff is the ruleset's diff for one history entry: the
+// configurations before and after it, got back by stepping back from
+// the current one through every later entry, rendered by this version.
+func (s *Server) historyDiff(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := require(p, auth.ResConfig, false); err != nil {
+		return err
+	}
+	id, err := pathID(r, "id")
+	if err != nil {
+		return err
+	}
+	hs, err := s.store.HistorySince(r.Context(), id)
+	if err != nil {
+		return err
+	}
+	if len(hs) == 0 || hs[len(hs)-1].ID != id {
+		return notFound("history entry %d not found", id)
+	}
+	st := s.eng.State()
+	var after *model.State
+	for _, h := range hs {
+		if h.ID == id {
+			after = st.Clone()
+		}
+		if err := engine.Rewind(st, h); err != nil {
+			return err
+		}
+	}
+	before, done := fmt.Sprintf("before %d", id), fmt.Sprintf("after %d", id)
+	writeJSON(w, http.StatusOK, map[string]string{"diff": s.labeledDiff(st, after, before, done)})
+	return nil
+}
+
 func (s *Server) revertHistory(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
 	if err := require(p, auth.ResConfig, true); err != nil {
 		return err
@@ -669,3 +854,19 @@ func (s *Server) rollbackChanges(w http.ResponseWriter, r *http.Request, p *auth
 	writeJSON(w, http.StatusOK, map[string]int{"rolled_back": n})
 	return nil
 }
+
+// listOwnBanLists lists the ban lists a principal without config:read
+// may use.
+func (s *Server) listOwnBanLists(w http.ResponseWriter, p *auth.Principal) error {
+	out := []*model.BanList{}
+	for _, b := range s.eng.State().BanLists {
+		if p.CanBan(b.Name, false) {
+			out = append(out, b)
+		}
+	}
+	if len(out) == 0 && !p.Can(auth.ResBans, false) {
+		return require(p, auth.ResConfig, false)
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}

internal/server/h_stats.go

@@ -150,8 +150,10 @@ func (s *Server) statsSummary(w http.ResponseWriter, r *http.Request, p *auth.Pr
 		return err
 	}
 	st := s.eng.State()
-	for i := range sum.Rules {
+	for _, es := range [][]stats.Entry{sum.Rules, sum.BuiltIns} {
-		sum.Rules[i].Name = markName(st, sum.Rules[i].Key)
+		for i := range es {
+			es[i].Name = markName(st, es[i].Key)
+		}
 	}
 	writeJSON(w, http.StatusOK, sum)
 	return nil

internal/server/h_status.go

@@ -84,16 +84,21 @@ var nftablesUnitLinks = []string{
 
 // hostProblems are warnings about the machine rather than the
 // configuration: another ruleset that still loads at boot, or the table
-// an import came from, still in force beside Housecarl's. ruleset is the
+// an import came from, still in force beside Housecarl's, and the Jarl
+// sets' names that give no addresses. ruleset is the
 // machine's (nft -j list ruleset; nil: not read). In shadow mode those
 // are expected; the warnings are that nothing else filters, and the raw
 // rules left out.
 func (s *Server) hostProblems(ctx context.Context, ruleset []byte) []validate.Problem {
+	var jarl []validate.Problem
+	if s.cfg.JarlSets != nil {
+		jarl = s.cfg.JarlSets.Problems(s.eng.State())
+	}
 	if s.cfg.Shadow {
-		return s.shadowProblems(ruleset)
+		return append(s.shadowProblems(ruleset), jarl...)
 	}
 	others := otherTables(ruleset)
-	var out []validate.Problem
+	out := jarl
 	for _, link := range s.unitLinks {
 		if _, err := os.Lstat(link); err == nil {
 			out = append(out, validate.Problem{Severity: validate.Warning, Code: "nftables_service", Object: "nftables.service",
@@ -284,6 +289,53 @@ func (s *Server) deleteElement(w http.ResponseWriter, r *http.Request, p *auth.P
 	return nil
 }
 
+// ---- Jarl sets
+
+// jarlSet is the Jarl set a request names.
+func (s *Server) jarlSet(r *http.Request, p *auth.Principal) (*model.State, *model.AddressSet, error) {
+	name := r.PathValue("ref")
+	if !p.CanSet(name, false) {
+		return nil, nil, forbidden("permission denied: this needs sets:read for %s", name)
+	}
+	st := s.eng.State()
+	set := st.Set(name)
+	if set == nil {
+		return nil, nil, notFound("no set %s", name)
+	}
+	if set.Jarl == nil {
+		return nil, nil, badRequest("set %s doesn't take its addresses from Jarl", set.Name)
+	}
+	if s.cfg.JarlSets == nil {
+		return nil, nil, conflict("this housecarld doesn't read Jarl sets")
+	}
+	return st, set, nil
+}
+
+// jarlStatus: GET /sets/{ref}/jarl.
+func (s *Server) jarlStatus(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, set, err := s.jarlSet(r, p)
+	if err != nil {
+		return err
+	}
+	writeJSON(w, http.StatusOK, s.cfg.JarlSets.Status(st, set))
+	return nil
+}
+
+// jarlRefresh: POST /sets/{ref}/jarl/refresh reads Jarl now (every Jarl
+// set) and answers as GET does.
+func (s *Server) jarlRefresh(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if _, _, err := s.jarlSet(r, p); err != nil {
+		return err
+	}
+	s.cfg.JarlSets.Refresh(r.Context())
+	st, set, err := s.jarlSet(r, p)
+	if err != nil {
+		return err
+	}
+	writeJSON(w, http.StatusOK, s.cfg.JarlSets.Status(st, set))
+	return nil
+}
+
 // ---- the log
 
 // logRing keeps the latest logged packets.

internal/server/jarlsets_test.go

@@ -0,0 +1,104 @@
+package server
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"housecarl/internal/api"
+	"housecarl/internal/jarl"
+	"housecarl/internal/jarlsets"
+	"housecarl/internal/model"
+	"housecarl/internal/store"
+)
+
+// TestJarlSets: a set from Jarl, through Housecarl's Jarl client against a
+// fake Jarl, filled after a change, with its status and warnings.
+func TestJarlSets(t *testing.T) {
+	records := []map[string]string{
+		{"name": "nas.example.com.", "type": "A", "data": "10.0.10.20"},
+		{"name": "nas.example.com.", "type": "AAAA", "data": "2001:db8:10::20"},
+		{"name": "files.example.com.", "type": "CNAME", "data": "nas.example.com."},
+		{"name": "far.example.com.", "type": "A", "data": "192.0.2.9"},
+	}
+	fake := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("Authorization") != "Bearer jarl-token" {
+			w.WriteHeader(401)
+			return
+		}
+		switch r.URL.Path {
+		case "/api/v1/zones":
+			json.NewEncoder(w).Encode([]map[string]any{{"id": 1, "name": "example.com.", "view": "internal", "type": "primary"}})
+		case "/api/v1/zones/1/records":
+			if r.URL.Query().Get("disabled") != "0" {
+				t.Errorf("records asked without disabled=0: %s", r.URL)
+			}
+			json.NewEncoder(w).Encode(records)
+		default:
+			w.WriteHeader(404)
+		}
+	}))
+	t.Cleanup(fake.Close)
+	jc, err := jarl.New(fake.URL, "jarl-token", "", false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	js := &jarlsets.Resolver{Source: jc}
+	e := newEnvWith(t, Config{JarlSets: js})
+	js.State, js.Connected = e.eng.State, e.srv.Connected
+	js.Apply = func(ctx context.Context) error { return e.eng.ApplyCurrent(ctx) }
+	js.Audit = func(ctx context.Context, set, detail string) {
+		e.eng.Audit(ctx, nil, "set.jarl", set, "success", detail)
+	}
+	ctx := context.Background()
+
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil) // 10.0.10.0/24
+	set := model.AddressSet{Name: "nas", Jarl: &model.JarlSource{Names: []model.JarlName{{Name: "files.example.com"}, {Name: "far.example.com", View: "internal"}}, Within: []string{"lan"}}}
+	if code := e.call(e.token, "POST", "/sets", set, nil); code != 201 {
+		t.Fatalf("create: %d", code)
+	}
+	if code := e.call(e.token, "POST", "/sets", model.AddressSet{Name: "bad", Entries: []string{"10.0.0.1"}, Jarl: set.Jarl}, nil); code != 422 {
+		t.Errorf("entries in a Jarl set: %d", code)
+	}
+	var st api.JarlSet
+	if code := e.call(e.token, "POST", "/sets/nas/jarl/refresh", nil, &st); code != 200 {
+		t.Fatalf("refresh: %d", code)
+	}
+	if strings.Join(st.Entries, ",") != "10.0.10.20" || len(st.Names) != 2 || !st.Configured || st.Read == nil {
+		t.Fatalf("status %+v", st)
+	}
+	files := st.Names[0]
+	if files.Found != "internal" || strings.Join(files.Chain, ",") != "nas.example.com" || len(files.Addresses) != 2 ||
+		!files.Addresses[0].Used || files.Addresses[1].Used || !strings.Contains(files.Addresses[1].Why, "not within lan") {
+		t.Errorf("files: %+v", files)
+	}
+	var status api.Status
+	e.call(e.token, "GET", "/status", nil, &status)
+	n := 0
+	for _, p := range status.Problems {
+		if p.Code == "jarl_outside" {
+			n++
+		}
+	}
+	if n != 2 {
+		t.Errorf("jarl_outside warnings: %d (%+v)", n, status.Problems)
+	}
+	// A Jarl set can be renamed (its addresses go by its names in Jarl).
+	if code := e.call(e.token, "PATCH", "/sets/nas", map[string]any{"name": "storage"}, nil); code != 200 {
+		t.Errorf("rename: %d", code)
+	}
+	if code := e.call(e.token, "GET", "/sets/trusted/jarl", nil, nil); code != 404 {
+		t.Errorf("no such set: %d", code)
+	}
+	e.call(e.token, "POST", "/sets", model.AddressSet{Name: "trusted", Entries: []string{"10.0.10.0/24"}}, nil)
+	if code := e.call(e.token, "GET", "/sets/trusted/jarl", nil, nil); code != 400 {
+		t.Errorf("a set not from Jarl: %d", code)
+	}
+	evs, _ := e.srv.store.ListAudit(ctx, store.AuditFilter{Action: "set.jarl"})
+	if len(evs) != 1 || evs[0].Detail != "added 10.0.10.20" {
+		t.Errorf("audit %+v", evs)
+	}
+}

internal/server/ops.go

@@ -104,6 +104,9 @@ func updateOp(st *model.State, op *model.Op) (int64, error) {
 		return 0, err
 	}
 	setID(next, id)
+	if old, now := o.Label(), next.Label(); old != now && op.Kind == model.KindBanList {
+		return 0, conflict("ban list %s can't be renamed: the API tokens and programs (Guard, fail2ban) that ban into it go by its name; make a new list instead", old)
+	}
 	if old, now := o.Label(), next.Label(); old != now && isNamed(op.Kind) {
 		if set, ok := o.(*model.AddressSet); ok && set.Dynamic {
 			return 0, conflict("set %s is dynamic: its entries, and the API tokens and programs that fill it, go by its name; make a new set instead", old)

internal/server/routes.go

@@ -38,6 +38,13 @@ func (s *Server) routes() {
 	m.HandleFunc("GET "+p+"/sets/{ref}/elements", s.authed(s.listElements))
 	m.HandleFunc("POST "+p+"/sets/{ref}/elements", s.authed(s.addElement))
 	m.HandleFunc("DELETE "+p+"/sets/{ref}/elements/{addr}", s.authed(s.deleteElement))
+	m.HandleFunc("GET "+p+"/sets/{ref}/jarl", s.authed(s.jarlStatus))
+	m.HandleFunc("POST "+p+"/sets/{ref}/jarl/refresh", s.authed(s.jarlRefresh))
+	m.HandleFunc("GET "+p+"/bans", s.authed(s.listBans))
+	m.HandleFunc("GET "+p+"/banlists/{ref}/bans", s.authed(s.listBans))
+	m.HandleFunc("POST "+p+"/banlists/{ref}/bans", s.authed(s.addBan))
+	m.HandleFunc("DELETE "+p+"/banlists/{ref}/bans", s.authed(s.deleteBans))
+	m.HandleFunc("DELETE "+p+"/banlists/{ref}/bans/{id}", s.authed(s.deleteBans))
 	m.HandleFunc("GET "+p+"/quotas", s.authed(s.listQuotas))
 	m.HandleFunc("GET "+p+"/connections", s.authed(s.listConnections))
 	m.HandleFunc("POST "+p+"/connections/close", s.authed(s.closeConnections))
@@ -70,6 +77,7 @@ func (s *Server) routes() {
 	m.HandleFunc("GET "+p+"/stats/heatmap", s.authed(s.statsHeatmap))
 	m.HandleFunc("GET "+p+"/history", s.authed(s.listHistory))
 	m.HandleFunc("GET "+p+"/history/{id}", s.authed(s.getHistory))
+	m.HandleFunc("GET "+p+"/history/{id}/diff", s.authed(s.historyDiff))
 	m.HandleFunc("POST "+p+"/history/{id}/revert", s.authed(s.revertHistory))
 	m.HandleFunc("GET "+p+"/probation", s.authed(s.getProbation))
 	m.HandleFunc("POST "+p+"/confirm", s.authed(s.confirmChanges))

internal/server/server.go

@@ -22,6 +22,7 @@ import (
 	"housecarl/internal/auth"
 	"housecarl/internal/certs"
 	"housecarl/internal/engine"
+	"housecarl/internal/jarlsets"
 	"housecarl/internal/model"
 	"housecarl/internal/names"
 	"housecarl/internal/nft"
@@ -54,6 +55,8 @@ type Config struct {
 	ShadowPosition string
 	// Names looks up inside addresses' names (nil: names are off).
 	Names *names.Resolver
+	// JarlSets fills the sets whose addresses come from Jarl (nil: none).
+	JarlSets *jarlsets.Resolver
 }
 
 // Interfaces lists the host's interfaces with their addresses, and
@@ -72,6 +75,8 @@ type Firewall interface {
 	Table(ctx context.Context) (*nft.Table, error)
 	AddElement(ctx context.Context, set, addr string, timeout int) error
 	DeleteElement(ctx context.Context, set, addr string) error
+	AddBan(ctx context.Context, b render.Ban) error
+	DeleteBan(ctx context.Context, b render.Ban) error
 	ListRuleset(ctx context.Context) ([]byte, error)
 	DeleteTable(ctx context.Context, family, name string) error
 	TableText(ctx context.Context, family, name string) (string, error)
@@ -141,6 +146,20 @@ func New(cfg Config, eng *engine.Engine, fw Firewall, ifaces Interfaces, log *sl
 	s := &Server{cfg: cfg, eng: eng, fw: fw, ifaces: ifaces, store: eng.Store(), log: log, mux: http.NewServeMux(), limiter: newRateLimiter(),
 		web: web, started: time.Now(), logs: newLogRing(2000), nowFn: time.Now, unitLinks: nftablesUnitLinks}
 	s.routes()
+	// What the quotas used is saved after every change too, not only every
+	// five minutes: a change that counts a quota differently converts its
+	// usage, and a restart must not bring back the old kind.
+	prev := eng.OnChange
+	eng.OnChange = func(st *model.State) {
+		if prev != nil {
+			prev(st)
+		}
+		s.SaveQuotaUsage(context.Background())
+		s.pruneBans(context.Background(), st) // the engine is locked: not s.eng.State()
+		if cfg.JarlSets != nil {
+			cfg.JarlSets.Kick() // a new name: read it now
+		}
+	}
 	return s
 }
 
@@ -314,6 +333,7 @@ func (s *Server) housekeeping(ctx context.Context) {
 				s.log.Warn("purging sessions failed", "err", err)
 			}
 			s.limiter.cleanup()
+			s.pruneBans(ctx, s.eng.State())
 			if s.certs != nil {
 				s.certs.reloadIfChanged()
 			}

internal/server/server_test.go

@@ -48,9 +48,25 @@ type fakeFW struct {
 	ruleset    string // nft -j list ruleset ("": a default)
 	quotas     nft.QuotaUsage
 	adjusted   []nft.QuotaAdjust
+	bans       map[string]render.Ban // by element (set and key)
 }
 
 func (f *fakeFW) Check(_ context.Context, st *model.State) error { return nil }
+func (f *fakeFW) AddBan(_ context.Context, b render.Ban) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.bans == nil {
+		f.bans = map[string]render.Ban{}
+	}
+	f.bans[render.BanSet(b.List, b.Addr.Addr().Is6(), b.Proto != "")+" "+render.BanElement(b)] = b
+	return nil
+}
+func (f *fakeFW) DeleteBan(_ context.Context, b render.Ban) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	delete(f.bans, render.BanSet(b.List, b.Addr.Addr().Is6(), b.Proto != "")+" "+render.BanElement(b))
+	return nil
+}
 func (f *fakeFW) Apply(_ context.Context, st *model.State) error {
 	f.mu.Lock()
 	defer f.mu.Unlock()
@@ -792,6 +808,21 @@ func TestQuotaResets(t *testing.T) {
 	}
 }
 
+// TestQuotaUsageSavedOnChange: a change saves what the quotas used at
+// once (a restart must not bring back usage counted the old way).
+func TestQuotaUsageSavedOnChange(t *testing.T) {
+	e := newEnv(t)
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "lan", Interfaces: []string{"eth1"}}, nil)
+	e.fw.mu.Lock()
+	e.fw.quotas = nft.QuotaUsage{Quotas: map[string]int64{"quota_r7": 4242}}
+	e.fw.mu.Unlock()
+	e.call(e.token, "POST", "/zones", model.Zone{Name: "dmz", Interfaces: []string{"eth2"}}, nil)
+	v, err := e.eng.Store().GetMeta(context.Background(), QuotaUsageKey)
+	if err != nil || !strings.Contains(v, `"quota_r7":4242`) {
+		t.Errorf("saved usage %q %v", v, err)
+	}
+}
+
 // TestAutoConfirm: the client that made a change confirms it by itself:
 // with its token, from the same address, over a new connection. Nobody
 // else can, an older token can't, and with manual_confirm there is none.
@@ -1304,3 +1335,77 @@ func TestCreatePlaced(t *testing.T) {
 		t.Errorf("%d rules", n)
 	}
 }
+
+// TestStagedMovesFold: moving a rule several steps in a changeset stays
+// one operation, and moving it back where it was takes it out.
+func TestStagedMovesFold(t *testing.T) {
+	e := newEnv(t)
+	var ids []int64
+	for _, svc := range []string{"ssh", "dns", "http", "https"} {
+		var mr api.MutationResponse
+		var r model.Rule
+		e.call(e.token, "POST", "/rules", model.Rule{Chain: "input", Match: model.Match{Services: []string{svc}}}, &mr)
+		json.Unmarshal(mr.Object, &r)
+		ids = append(ids, r.ID)
+	}
+	var cs model.Changeset
+	e.call(e.token, "POST", "/changesets", nil, &cs)
+	q := "?changeset=" + itoa(cs.ID)
+	var mr api.MutationResponse
+	for _, before := range []int64{ids[2], ids[1], ids[0]} { // https up three steps
+		if code := e.call(e.token, "POST", "/rules/"+itoa(ids[3])+"/move"+q, api.MoveInput{Before: before}, &mr); code != 200 || !mr.Staged {
+			t.Fatalf("move before %d: %d %+v", before, code, mr)
+		}
+	}
+	if n := len(mr.Changeset.Ops); n != 1 {
+		t.Fatalf("%d operations, want 1: %+v", n, mr.Changeset.Ops)
+	}
+	// Another operation in between: the next move is its own.
+	e.call(e.token, "PATCH", "/rules/"+itoa(ids[0])+q, map[string]any{"comment": "x"}, nil)
+	e.call(e.token, "POST", "/rules/"+itoa(ids[3])+"/move"+q, api.MoveInput{After: ids[0]}, &mr)
+	if n := len(mr.Changeset.Ops); n != 3 {
+		t.Errorf("%d operations after a patch and a move, want 3", n)
+	}
+	// Back to the start: the same place as before that move, so it goes.
+	e.call(e.token, "POST", "/rules/"+itoa(ids[3])+"/move"+q, api.MoveInput{To: "start"}, &mr)
+	if n := len(mr.Changeset.Ops); n != 2 {
+		t.Errorf("%d operations after moving back, want 2", n)
+	}
+	if code := e.call(e.token, "POST", "/changesets/"+itoa(cs.ID)+"/apply", nil, nil); code != 200 {
+		t.Fatalf("apply: %d", code)
+	}
+	var out []string
+	for _, r := range e.eng.State().Rules {
+		out = append(out, strings.Join(r.Services, ""))
+	}
+	if o := strings.Join(out, ","); o != "https,ssh,dns,http" {
+		t.Errorf("order: %s", o)
+	}
+}
+
+// TestTokenForUser: an administrator makes a token for another user (the
+// web UI's New token on a user's row); that user can't make one for
+// someone else.
+func TestTokenForUser(t *testing.T) {
+	e := newEnv(t)
+	var u api.User
+	if code := e.call(e.token, "POST", "/users", api.UserInput{Username: ptr("portal"), Grants: &[]string{"sets:write"}}, &u); code != 201 {
+		t.Fatalf("user: %d", code)
+	}
+	var tok api.Token
+	if code := e.call(e.token, "POST", "/users/"+itoa(u.ID)+"/tokens", api.TokenInput{Name: "portal", ExpiresIn: "30d"}, &tok); code != 201 || tok.Secret == "" || tok.UserID != u.ID {
+		t.Fatalf("token for portal: %d %+v", code, tok)
+	}
+	if code := e.call(tok.Secret, "GET", "/rules", nil, nil); code != 403 {
+		t.Errorf("the token can do more than its user: %d", code)
+	}
+	var users []api.User
+	e.call(e.token, "GET", "/users", nil, &users)
+	for _, o := range users {
+		if o.ID != u.ID {
+			if code := e.call(tok.Secret, "POST", "/users/"+itoa(o.ID)+"/tokens", api.TokenInput{Name: "x"}, nil); code != 403 {
+				t.Errorf("a token for another user, made by a non-administrator: %d", code)
+			}
+		}
+	}
+}

internal/stats/collector.go

@@ -402,7 +402,10 @@ func (c *Collector) sample(ctx context.Context, minute int64) map[string]int64 {
 			for set, es := range t.QuotaSets {
 				kind := strings.TrimSuffix(strings.TrimSuffix(set, "_v4"), "_v6")
 				for _, e := range es {
-					addTop(kind, e.Addr, c.table.of(set+"/"+e.Addr, e.Used))
+					d := c.table.of(set+"/"+e.Addr, e.Used)
+					addTop(kind, e.Addr, d)
+					// A per-address quota's series is its addresses' sum.
+					add("quota:"+strings.TrimPrefix(kind, "quota_"), d)
 				}
 			}
 			for set, es := range t.DeviceSets {

internal/stats/collector_test.go

@@ -7,6 +7,7 @@ import (
 	"log/slog"
 	"os"
 	"path/filepath"
+	"slices"
 	"testing"
 	"time"
 
@@ -85,6 +86,10 @@ func TestCollector(t *testing.T) {
 	h.table.Counters["r1"] = nft.Counter{Packets: 10, Bytes: 1000}
 	h.table.Counters["r2"] = nft.Counter{Packets: 100, Bytes: 9000}
 	h.table.Quotas["quota_r5"] = 1 << 20
+	if h.table.QuotaSets == nil {
+		h.table.QuotaSets = map[string][]render.Element{}
+	}
+	h.table.QuotaSets["quota_r6_v4"] = []render.Element{{Addr: "10.0.10.5", Used: 1000}}
 	h.table.DeviceSets["stats_up_v4"] = []render.Element{{Addr: "10.0.10.5", Bytes: 5000}}
 
 	store, err := OpenStore(":memory:")
@@ -104,6 +109,7 @@ func TestCollector(t *testing.T) {
 	h.table.Counters["r1"] = nft.Counter{Packets: 25, Bytes: 2500}
 	h.table.Counters["p-input"] = nft.Counter{Packets: 3, Bytes: 180} // a new counter counts whole
 	h.table.Quotas["quota_r5"] = 3 << 20
+	h.table.QuotaSets["quota_r6_v4"] = []render.Element{{Addr: "10.0.10.5", Used: 2000}, {Addr: "10.0.10.6", Used: 500}} // a new entry counts whole
 	h.table.DeviceSets["stats_up_v4"] = []render.Element{{Addr: "10.0.10.5", Bytes: 8000}}
 	h.table.DeviceSets["stats_down_v6"] = []render.Element{{Addr: "2001:db8:1:2::", Bytes: 70000}}
 	for range 2 {
@@ -142,12 +148,21 @@ func TestCollector(t *testing.T) {
 	check("drop:forward", sum("drop:")["forward"], 15)
 	check("drop:input", sum("drop:")["input"], 3)
 	check("quota:r5", sum("quota:")["r5"], 2<<20)
+	check("quota:r6 (per address: the sum)", sum("quota:")["r6"], 1500)
 
 	s, err := q.Summary(ctx, time.Hour, 10)
 	if err != nil {
 		t.Fatal(err)
 	}
 	check("drops", s.Drops, 18)
+	for _, e := range s.Rules {
+		if e.Key[0] == 'b' || e.Key[0] == 'p' {
+			t.Errorf("built-in or policy %s among the busiest rules %+v", e.Key, s.Rules)
+		}
+	}
+	if !slices.ContainsFunc(s.Rules, func(e Entry) bool { return e.Key == "r1" }) || !slices.ContainsFunc(s.BuiltIns, func(e Entry) bool { return e.Key == "p-input" }) {
+		t.Errorf("rules %+v, built-ins %+v", s.Rules, s.BuiltIns)
+	}
 	if len(s.Zones) == 0 || s.Zones[0].Name != "wan" || s.Zones[0].Received != 4000 {
 		t.Errorf("zones %+v", s.Zones)
 	}

internal/stats/query.go

@@ -191,8 +191,11 @@ type Summary struct {
 	// chain.
 	Drops        int64   `json:"drops"`
 	DropsByChain []Entry `json:"drops_by_chain"`
-	// Rules are the busiest rules, built-ins and policies, by packets.
+	// Rules are the busiest rules and NAT objects, by packets; BuiltIns
+	// the busiest built-ins and policies, kept apart because the
+	// established built-in counts most of the traffic.
 	Rules    []Entry `json:"rules"`
+	BuiltIns []Entry `json:"builtins"`
 	// Connections: the most tracked at once (per-bucket averages), and
 	// the table's size.
 	PeakConnections int64   `json:"peak_connections"`
@@ -251,9 +254,15 @@ func (q *Querier) Summary(ctx context.Context, since time.Duration, topLimit int
 	s.Zones, s.Interfaces = traffic("zrx:", "ztx:"), traffic("rx:", "tx:")
 	s.Drops = all["drops"]
 	s.DropsByChain = sorted(all, "drop:")
-	s.Rules = sorted(all, "hits:")
+	s.Rules, s.BuiltIns = []Entry{}, []Entry{}
-	if len(s.Rules) > topLimit {
+	for _, e := range sorted(all, "hits:") {
-		s.Rules = s.Rules[:topLimit]
+		if strings.HasPrefix(e.Key, "b-") || strings.HasPrefix(e.Key, "p-") {
+			if len(s.BuiltIns) < topLimit {
+				s.BuiltIns = append(s.BuiltIns, e)
+			}
+		} else if len(s.Rules) < topLimit {
+			s.Rules = append(s.Rules, e)
+		}
 	}
 	if tl, err := q.Timeline(ctx, since, "auto", []string{"g:" + GaugeConntrack, "g:" + GaugeConntrackMax}); err == nil {
 		for _, v := range tl.Series[0].Values {

internal/store/bans.go

@@ -0,0 +1,135 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"time"
+
+	"housecarl/internal/model"
+)
+
+const banCols = `id, list_id, address, protocol, port, expires_at, created_at, who, source, reason`
+
+func scanBan(sc interface{ Scan(...any) error }, now time.Time) (*model.Ban, error) {
+	b := &model.Ban{}
+	var expires sql.NullString
+	var created string
+	if err := sc.Scan(&b.ID, &b.ListID, &b.Address, &b.Protocol, &b.Port, &expires, &created, &b.Who, &b.Source, &b.Reason); err != nil {
+		return nil, err
+	}
+	b.Created = parseTS(created)
+	b.Expires = parseTSPtr(expires)
+	if b.Expires != nil {
+		b.Timeout = max(int(b.Expires.Sub(now).Round(time.Second)/time.Second), 1)
+	}
+	return b, nil
+}
+
+// PutBan saves a ban, or renews the same ban (list, address, protocol
+// and port) with its new end, who and why (an empty source or reason
+// keeps the old). existing tells which; b gets
+// its ID either way.
+func (s *Store) PutBan(ctx context.Context, b *model.Ban) (existing bool, err error) {
+	now := time.Now()
+	err = s.db.QueryRowContext(ctx, `SELECT id FROM bans WHERE list_id = ? AND address = ? AND protocol = ? AND port = ?
+		AND (expires_at IS NULL OR expires_at > ?)`, b.ListID, b.Address, b.Protocol, b.Port, ts(now)).Scan(&b.ID)
+	existing = err == nil
+	if err != nil && !errors.Is(err, sql.ErrNoRows) {
+		return false, err
+	}
+	b.Created = now
+	err = s.db.QueryRowContext(ctx, `INSERT INTO bans (list_id, address, protocol, port, expires_at, created_at, who, source, reason)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
+		ON CONFLICT (list_id, address, protocol, port) DO UPDATE SET expires_at = excluded.expires_at,
+			who = excluded.who, source = COALESCE(NULLIF(excluded.source, ''), bans.source),
+			reason = COALESCE(NULLIF(excluded.reason, ''), bans.reason),
+			created_at = CASE WHEN bans.expires_at IS NULL OR bans.expires_at > excluded.created_at THEN bans.created_at ELSE excluded.created_at END
+		RETURNING id, created_at`,
+		b.ListID, b.Address, b.Protocol, b.Port, tsPtr(b.Expires), ts(now), b.Who, b.Source, b.Reason).Scan(&b.ID, new(string))
+	return existing, err
+}
+
+// ListBans lists the active bans of a list (0: of all lists), oldest
+// first.
+func (s *Store) ListBans(ctx context.Context, listID int64) ([]*model.Ban, error) {
+	now := time.Now()
+	q := `SELECT ` + banCols + ` FROM bans WHERE (expires_at IS NULL OR expires_at > ?)`
+	args := []any{ts(now)}
+	if listID != 0 {
+		q += ` AND list_id = ?`
+		args = append(args, listID)
+	}
+	rows, err := s.db.QueryContext(ctx, q+` ORDER BY id`, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	out := []*model.Ban{}
+	for rows.Next() {
+		b, err := scanBan(rows, now)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, b)
+	}
+	return out, rows.Err()
+}
+
+// GetBan loads an active ban.
+func (s *Store) GetBan(ctx context.Context, id int64) (*model.Ban, error) {
+	now := time.Now()
+	b, err := scanBan(s.db.QueryRowContext(ctx, `SELECT `+banCols+` FROM bans WHERE id = ? AND (expires_at IS NULL OR expires_at > ?)`, id, ts(now)), now)
+	if errors.Is(err, sql.ErrNoRows) {
+		return nil, ErrNotFound
+	}
+	return b, err
+}
+
+// DeleteBan removes a ban.
+func (s *Store) DeleteBan(ctx context.Context, id int64) error {
+	_, err := s.db.ExecContext(ctx, `DELETE FROM bans WHERE id = ?`, id)
+	return err
+}
+
+// CountBans counts a list's active bans.
+func (s *Store) CountBans(ctx context.Context, listID int64) (int, error) {
+	var n int
+	err := s.db.QueryRowContext(ctx, `SELECT COUNT(*) FROM bans WHERE list_id = ? AND (expires_at IS NULL OR expires_at > ?)`, listID, ts(time.Now())).Scan(&n)
+	return n, err
+}
+
+// PruneBans deletes the bans that ended, and those of lists that no
+// longer exist (lists names the ones that do).
+func (s *Store) PruneBans(ctx context.Context, lists []int64) (int64, error) {
+	res, err := s.db.ExecContext(ctx, `DELETE FROM bans WHERE expires_at <= ?`, ts(time.Now()))
+	if err != nil {
+		return 0, err
+	}
+	n, _ := res.RowsAffected()
+	rows, err := s.db.QueryContext(ctx, `SELECT DISTINCT list_id FROM bans`)
+	if err != nil {
+		return n, err
+	}
+	var gone []int64
+	keep := map[int64]bool{}
+	for _, id := range lists {
+		keep[id] = true
+	}
+	for rows.Next() {
+		var id int64
+		if rows.Scan(&id) == nil && !keep[id] {
+			gone = append(gone, id)
+		}
+	}
+	rows.Close()
+	for _, id := range gone {
+		res, err := s.db.ExecContext(ctx, `DELETE FROM bans WHERE list_id = ?`, id)
+		if err != nil {
+			return n, err
+		}
+		m, _ := res.RowsAffected()
+		n += m
+	}
+	return n, nil
+}

internal/store/history.go

@@ -63,3 +63,21 @@ func (s *Store) GetHistory(ctx context.Context, id int64) (*model.HistoryEntry,
 	}
 	return e, err
 }
+
+// HistorySince lists the entries from id on, newest first.
+func (s *Store) HistorySince(ctx context.Context, id int64) ([]*model.HistoryEntry, error) {
+	rows, err := s.db.QueryContext(ctx, `SELECT `+historyCols+` FROM history WHERE id >= ? ORDER BY id DESC`, id)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []*model.HistoryEntry
+	for rows.Next() {
+		e, err := scanHistory(rows)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, e)
+	}
+	return out, rows.Err()
+}

internal/store/store.go

@@ -179,6 +179,23 @@ CREATE TABLE changesets (
 	history_id INTEGER
 );
 CREATE INDEX changesets_status ON changesets (status);
+`,
+	// 3: ban lists' bans (the lists are objects)
+	`
+CREATE TABLE bans (
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	list_id INTEGER NOT NULL,
+	address TEXT NOT NULL,
+	protocol TEXT NOT NULL DEFAULT '',
+	port INTEGER NOT NULL DEFAULT 0,
+	expires_at TEXT,
+	created_at TEXT NOT NULL,
+	who TEXT NOT NULL DEFAULT '',
+	source TEXT NOT NULL DEFAULT '',
+	reason TEXT NOT NULL DEFAULT '',
+	UNIQUE (list_id, address, protocol, port)
+);
+CREATE INDEX bans_expires ON bans (expires_at);
 `,
 }
 

internal/store/store_test.go

@@ -103,3 +103,60 @@ func TestUsersAndAudit(t *testing.T) {
 		t.Errorf("audit %+v", evs)
 	}
 }
+
+func TestBans(t *testing.T) {
+	ctx := context.Background()
+	s, err := Open(filepath.Join(t.TempDir(), "housecarl.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer s.Close()
+	in := func(d time.Duration) *time.Time { t := time.Now().Add(d); return &t }
+	b := &model.Ban{ListID: 7, Address: "203.0.113.9", Expires: in(time.Hour), Who: "guard", Source: "guard/ssh"}
+	if existing, err := s.PutBan(ctx, b); err != nil || existing {
+		t.Fatalf("new ban: %v %v", existing, err)
+	}
+	id := b.ID
+	again := &model.Ban{ListID: 7, Address: "203.0.113.9", Expires: in(2 * time.Hour), Who: "guard", Reason: "again"}
+	if existing, err := s.PutBan(ctx, again); err != nil || !existing || again.ID != id {
+		t.Fatalf("renewed ban: %v %v id %d, want %d", existing, err, again.ID, id)
+	}
+	port := &model.Ban{ListID: 7, Address: "2001:db8:1:2::/64", Protocol: "tcp", Port: 22}
+	if _, err := s.PutBan(ctx, port); err != nil {
+		t.Fatal(err)
+	}
+	gone := &model.Ban{ListID: 7, Address: "198.51.100.1", Expires: in(-time.Second)}
+	if _, err := s.PutBan(ctx, gone); err != nil {
+		t.Fatal(err)
+	}
+	other := &model.Ban{ListID: 8, Address: "198.51.100.2"}
+	if _, err := s.PutBan(ctx, other); err != nil {
+		t.Fatal(err)
+	}
+	list, err := s.ListBans(ctx, 7)
+	if err != nil || len(list) != 2 {
+		t.Fatalf("list 7: %v %+v", err, list)
+	}
+	if list[0].Reason != "again" || list[0].Timeout < 7100 || list[0].Timeout > 7200 || list[1].Expires != nil || list[1].Timeout != 0 {
+		t.Errorf("bans: %+v %+v", list[0], list[1])
+	}
+	if n, _ := s.CountBans(ctx, 7); n != 2 {
+		t.Errorf("count %d", n)
+	}
+	// An ended ban is renewed as new.
+	if existing, _ := s.PutBan(ctx, &model.Ban{ListID: 7, Address: "198.51.100.1", Expires: in(time.Minute)}); existing {
+		t.Error("an ended ban counted as existing")
+	}
+	if n, err := s.PruneBans(ctx, []int64{7}); err != nil || n != 1 {
+		t.Errorf("prune: %d %v (list 8's ban)", n, err)
+	}
+	if all, _ := s.ListBans(ctx, 0); len(all) != 3 {
+		t.Errorf("after pruning: %+v", all)
+	}
+	if err := s.DeleteBan(ctx, id); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := s.GetBan(ctx, id); !errors.Is(err, ErrNotFound) {
+		t.Errorf("deleted ban: %v", err)
+	}
+}

internal/validate/validate.go

@@ -82,6 +82,7 @@ func Check(st *model.State, env *Env) []Problem {
 	for _, x := range st.Redirects {
 		c.redirect(x)
 	}
+	c.banLists()
 	return c.out
 }
 
@@ -173,6 +174,8 @@ func (c *checker) settings() {
 			}
 			if l.v6 != 2 && a.IsV6() != (l.v6 == 1) {
 				c.add(Error, "settings_address", "settings", "%s: %s is the wrong address family", l.name, e)
+			} else if a.Overlaps(model.LinkLocal6) {
+				c.add(Error, "antispoof_link_local", "settings", "%s: %s holds link-local addresses (fe80::/10), which your ISP's router sends its router adverts and DHCPv6 replies from: dropping them on external zones loses the IPv6 default route, and later the delegated prefix. Link-local addresses never come from the internet anyway; take %s out", l.name, e, e)
 			}
 		}
 	}
@@ -233,9 +236,9 @@ func (c *checker) sets() {
 	for _, s := range c.st.Sets {
 		obj := "set " + s.Name
 		c.name("set", obj, s.Name, seen)
-		for _, pre := range []string{"meter_", "conn_", "quota_", "stats_"} {
+		for _, pre := range []string{"meter_", "conn_", "quota_", "stats_", "ban_"} {
 			if strings.HasPrefix(strings.ToLower(s.Name), pre) {
-				c.add(Error, "set_name_reserved", obj, "set names starting with %s are Housecarl's own (rate limits, quotas, statistics); choose another name", pre)
+				c.add(Error, "set_name_reserved", obj, "set names starting with %s are Housecarl's own (rate limits, quotas, statistics, ban lists); choose another name", pre)
 			}
 		}
 		for _, e := range s.Entries {
@@ -246,15 +249,79 @@ func (c *checker) sets() {
 		if len(s.Entries) > 0 && s.Dynamic {
 			c.add(Error, "set_dynamic_entries", obj, "a dynamic set gets its entries at run time (hc set entries add, the Entries button), each with its timeout; leave out the configured ones, or make it a set that isn't dynamic")
 		}
-		if len(s.Entries) == 0 && !s.Dynamic {
+		if len(s.Entries) == 0 && !s.Runtime() {
 			c.add(Warning, "set_empty", obj, "the set is empty: rules using it match nothing")
 		}
+		if s.Jarl != nil {
+			c.jarlSet(obj, s)
+		}
 		if s.Timeout < 0 || s.Timeout > 0 && !s.Dynamic {
 			c.add(Error, "set_timeout", obj, "only a dynamic set has a timeout, of 1 second or more")
 		}
 	}
 }
 
+// dnsLabel is one label of a name in Jarl (underscores allowed, as in
+// _service names).
+var dnsLabel = regexp.MustCompile(`^[a-z0-9_]([a-z0-9_-]{0,61}[a-z0-9_])?$`)
+
+// jarlSet checks a set whose entries come from Jarl.
+func (c *checker) jarlSet(obj string, s *model.AddressSet) {
+	j := s.Jarl
+	if len(s.Entries) > 0 {
+		c.add(Error, "set_jarl_entries", obj, "a Jarl set's entries are the addresses of its names in Jarl; leave out the configured ones, or make it a set that doesn't come from Jarl")
+	}
+	if s.Dynamic {
+		c.add(Error, "set_jarl_dynamic", obj, "a set is dynamic or comes from Jarl, not both")
+	}
+	if len(j.Names) == 0 {
+		c.add(Error, "set_jarl_names", obj, "name at least one name in Jarl, such as nas.example.com (or nas.example.com@internal for one view)")
+	}
+	seen := map[string]bool{}
+	for _, n := range j.Names {
+		if !validDNSName(n.Name) {
+			c.add(Error, "set_jarl_names", obj, "%q isn't a DNS name; give the full name, such as nas.example.com (wildcards aren't followed)", n.Name)
+			continue
+		}
+		if strings.ContainsAny(n.View, " \t@") {
+			c.add(Error, "set_jarl_names", obj, "%q isn't a view name: write NAME@VIEW, such as nas.example.com@internal", n.View)
+			continue
+		}
+		if seen[n.String()] {
+			c.add(Error, "set_jarl_names", obj, "%s is listed twice", n)
+		}
+		seen[n.String()] = true
+	}
+	if len(j.Within) == 0 {
+		c.add(Error, "set_jarl_within", obj, "say where its addresses may be (within): zones, whose connected networks count, or networks such as 10.10.0.0/24; an address from Jarl elsewhere is left out, so a changed record can't open the firewall to anything")
+	}
+	for _, w := range j.Within {
+		if a, err := model.ParseAddress(w); err == nil {
+			if a.Prefix.IsValid() && a.Prefix.Bits() == 0 && !a.First.IsValid() {
+				c.add(Warning, "set_jarl_anywhere", obj, "within %s lets any address in: whoever can change the names in Jarl decides what the set holds; name zones or networks instead", w)
+			}
+			continue
+		}
+		if c.st.Zone(w) == nil {
+			c.add(Error, "set_jarl_within", obj, "within %q: no such zone, and not an address or network", w)
+		}
+	}
+}
+
+// validDNSName reports whether n is a name a Jarl set can look up: LDH
+// labels (and underscores), no wildcard, without the final dot.
+func validDNSName(n string) bool {
+	if n == "" || len(n) > 253 {
+		return false
+	}
+	for _, l := range strings.Split(n, ".") {
+		if !dnsLabel.MatchString(l) {
+			return false
+		}
+	}
+	return true
+}
+
 func (c *checker) services() {
 	seen := map[string]string{}
 	for _, s := range c.st.Services {
@@ -612,3 +679,48 @@ func (c *checker) redirect(x *model.Redirect) {
 		}
 	}
 }
+
+func (c *checker) banLists() {
+	seen := map[string]string{}
+	for _, b := range c.st.BanLists {
+		obj := "ban list " + b.Name
+		c.name("banlist", obj, b.Name, seen)
+		known := false
+		for _, sc := range model.BanScopes {
+			known = known || b.Scope == sc
+		}
+		if !known {
+			c.add(Error, "banlist_scope", obj, "the scope is %q; use firewall (the firewall itself), hosts (the list's hosts) or everything", b.Scope)
+		}
+		switch {
+		case b.Scope == model.BanScopeHosts && len(b.Hosts) == 0:
+			c.add(Error, "banlist_hosts", obj, "a list with scope hosts needs its hosts: the addresses, or sets, of the machines it protects")
+		case b.Scope != model.BanScopeHosts && len(b.Hosts) > 0:
+			c.add(Error, "banlist_hosts", obj, "only a list with scope hosts has hosts; leave them out, or use scope hosts")
+		}
+		refs := func(what string, list []string) {
+			for _, r := range list {
+				if !model.IsLiteral(r) && c.st.Set(r) == nil {
+					if _, err := model.ParseAddress(r); strings.ContainsAny(r, "./:") {
+						c.add(Error, "banlist_address", obj, "%s: %v", what, err)
+					} else {
+						c.add(Error, "unknown_set", obj, "%s: there is no set %s", what, r)
+					}
+				}
+			}
+		}
+		refs("hosts", b.Hosts)
+		refs("never", b.Never)
+		if b.DefaultTime < 0 || b.MaxTime < -1 {
+			c.add(Error, "banlist_time", obj, "ban times are seconds: default_time 0 (an hour) or more, max_time 0 (a week), more, or -1 for no limit")
+		} else if max := b.BanMaxTime(); max > 0 && b.BanTime() > max {
+			c.add(Error, "banlist_time", obj, "the default ban time (%ds) is longer than the longest (%ds)", b.BanTime(), max)
+		}
+		if b.MaxEntries < 0 || b.MaxEntries > 1000000 {
+			c.add(Error, "banlist_entries", obj, "max_entries is %d; use 1 to 1000000, or 0 for 10000", b.MaxEntries)
+		}
+		if b.GroupV6 != 0 && (b.GroupV6 < 16 || b.GroupV6 > 128) {
+			c.add(Error, "banlist_group", obj, "group_v6 is /%d; use 16 to 128 (64 bans what one customer usually gets, 128 one address)", b.GroupV6)
+		}
+	}
+}

internal/validate/validate_test.go

@@ -25,6 +25,20 @@ func base() *model.State {
 		Forwards: []*model.PortForward{{ID: 7, Position: 1, Name: "jellyfin", Protocols: []string{"tcp"}, Ports: "8096", To: "10.0.10.57",
 			PublicAddresses: []string{"203.0.113.7"}, Hairpin: true}},
 		SNATs:    []*model.SourceNAT{{ID: 8, Position: 1, Match: model.Match{OutZones: []string{"wan"}, Sources: []string{"trusted"}}}},
+		BanLists: []*model.BanList{{ID: 9, Name: "web", Scope: model.BanScopeHosts, Hosts: []string{"10.0.10.57"}, Never: []string{"trusted"}}},
+	}
+}
+
+func jarlSource() *model.JarlSource {
+	return &model.JarlSource{Names: []model.JarlName{{Name: "nas.example.com", View: "internal"}}, Within: []string{"lan", "10.9.0.0/16"}}
+}
+
+func TestJarlSetValid(t *testing.T) {
+	st := base()
+	st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+	st.Sets[0].Jarl.Names = append(st.Sets[0].Jarl.Names, model.JarlName{Name: "_svc.files.example.com"})
+	if ps := Check(st, nil); len(ps) > 0 {
+		t.Fatalf("problems: %+v", ps)
 	}
 }
 
@@ -54,6 +68,9 @@ func TestCodes(t *testing.T) {
 		{"forward_name", func(st *model.State) { st.Forwards[0].Name = "jelly fin" }},
 		{"policy", func(st *model.State) { st.Settings.InputPolicy = "reject" }},
 		{"settings_address", func(st *model.State) { st.Settings.AntispoofV4 = []string{"fc00::/7"} }},
+		{"antispoof_link_local", func(st *model.State) { st.Settings.AntispoofV6 = []string{"fc00::/7", "fe80::/10"} }},
+		{"antispoof_link_local", func(st *model.State) { st.Settings.OwnPrefixes = []string{"fe80::/64"} }},
+		{"antispoof_link_local", func(st *model.State) { st.Settings.AntispoofV6 = []string{"::/0"} }},
 		{"flowtable_device", func(st *model.State) { st.Settings.FlowtableDevices = []string{"eth*"} }},
 		{"probation_range", func(st *model.State) { st.Settings.ProbationSeconds = 5 }},
 		{"zone_empty", func(st *model.State) { st.Zones[1].Interfaces = nil }},
@@ -76,6 +93,33 @@ func TestCodes(t *testing.T) {
 		}},
 		{"set_timeout", func(st *model.State) { st.Sets[0].Timeout = 60 }},
 		{"set_dynamic_entries", func(st *model.State) { st.Sets[0].Dynamic = true }},
+		{"set_jarl_entries", func(st *model.State) { st.Sets[0].Jarl = jarlSource() }},
+		{"set_jarl_dynamic", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Dynamic, st.Sets[0].Jarl = nil, true, jarlSource()
+		}},
+		{"set_jarl_names", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, &model.JarlSource{Within: []string{"lan"}}
+		}},
+		{"set_jarl_names", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+			st.Sets[0].Jarl.Names[0].Name = "*.example.com"
+		}},
+		{"set_jarl_names", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+			st.Sets[0].Jarl.Names = append(st.Sets[0].Jarl.Names, st.Sets[0].Jarl.Names[0])
+		}},
+		{"set_jarl_within", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+			st.Sets[0].Jarl.Within = nil
+		}},
+		{"set_jarl_within", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+			st.Sets[0].Jarl.Within = []string{"dmz"}
+		}},
+		{"set_jarl_anywhere", func(st *model.State) {
+			st.Sets[0].Entries, st.Sets[0].Jarl = nil, jarlSource()
+			st.Sets[0].Jarl.Within = []string{"::/0"}
+		}},
 		{"service_empty", func(st *model.State) { st.Services[0].Entries = nil }},
 		{"service_entry", func(st *model.State) { st.Services[0].Entries = []string{"tcp/99999"} }},
 		{"unknown_zone", func(st *model.State) { st.Rules[1].InZones = []string{"dmz"} }},
@@ -136,6 +180,17 @@ func TestCodes(t *testing.T) {
 		{"redirect_service", func(st *model.State) {
 			st.Redirects = []*model.Redirect{{ID: 11, Position: 1, Match: model.Match{InZones: []string{"lan"}}}}
 		}},
+		{"banlist_name", func(st *model.State) { st.BanLists[0].Name = "web list" }},
+		{"banlist_scope", func(st *model.State) { st.BanLists[0].Scope = "world" }},
+		{"banlist_hosts", func(st *model.State) { st.BanLists[0].Hosts = nil }},
+		{"banlist_hosts", func(st *model.State) { st.BanLists[0].Scope = model.BanScopeFirewall }},
+		{"banlist_address", func(st *model.State) { st.BanLists[0].Never = []string{"10.0.0.300"} }},
+		{"unknown_set", func(st *model.State) { st.BanLists[0].Hosts = []string{"webservers"} }},
+		{"banlist_time", func(st *model.State) { st.BanLists[0].MaxTime = -2 }},
+		{"banlist_time", func(st *model.State) { st.BanLists[0].DefaultTime, st.BanLists[0].MaxTime = 7200, 3600 }},
+		{"banlist_entries", func(st *model.State) { st.BanLists[0].MaxEntries = -1 }},
+		{"banlist_group", func(st *model.State) { st.BanLists[0].GroupV6 = 8 }},
+		{"set_name_reserved", func(st *model.State) { st.Sets[0].Name = "ban_3" }},
 		{"redirect_to_port", func(st *model.State) {
 			st.Redirects = []*model.Redirect{{ID: 11, Position: 1, Match: model.Match{InZones: []string{"lan"}, Services: []string{"dns"}}, ToPort: "53-54"}}
 		}},

internal/web/static/assets/app.js

@@ -4,6 +4,7 @@ import { wordmark, logo } from "./brand.js";
 import { api, get, state, can, setUnauthorizedHandler, setChangeHandler, loadDraft, onDraftChange, setImmediate, useDraft } from "./api.js";
 import * as changes from "./pages/changes.js";
 import * as connections from "./pages/connections.js";
+import * as bans from "./pages/bans.js";
 import * as tracePage from "./pages/trace.js";
 import * as matrixPage from "./pages/matrix.js";
 import * as statsPage from "./pages/stats.js";
@@ -32,6 +33,7 @@ const routes = [
   { pattern: /^services$/, page: services, nav: "services" },
   { pattern: /^log$/, page: log, nav: "log" },
   { pattern: /^connections$/, page: connections, nav: "connections" },
+  { pattern: /^bans$/, page: bans, nav: "bans" },
   { pattern: /^trace$/, page: tracePage, nav: "trace" },
   { pattern: /^stats$/, page: statsPage, nav: "stats" },
   { pattern: /^settings$/, page: settings, nav: "settings" },
@@ -60,6 +62,7 @@ const navItems = [
     ["stats", "#/stats", "Statistics", "log"],
     ["log", "#/log", "Log", "log"],
     ["connections", "#/connections", "Connections", "log"],
+    ["bans", "#/bans", "Bans", "bans"],
     ["trace", "#/trace", "Trace", "log"],
   ] },
   ["changes", "#/changes", "Changes", "config"],

internal/web/static/assets/charts.js

@@ -331,7 +331,7 @@ export function heatmapTable(hm, unit) {
 // so the list is its own table view.
 // extra(key), when given, adds something after an entry's label (e.g. a
 // link that excludes it).
-export function barList(entries, { total, label = (k) => k, empty = "No data yet.", href, extra, format = compact } = {}) {
+export function barList(entries, { total, label = (k) => k, empty = "No data yet.", href, extra, format = compact, share: showShare = true } = {}) {
   if (!entries.length) return h("div", { class: "empty" }, empty);
   // Entries may be in a natural order (e.g. latency buckets), not by size.
   const peak = Math.max(1, ...entries.map((e) => e.count));
@@ -345,7 +345,7 @@ export function barList(entries, { total, label = (k) => k, empty = "No data yet
     return h("li", { title: (e.name ? e.name + " (" + name + ")" : name) + ": " + format(e.count) + " (" + share.toFixed(1) + "%)" },
       h("div", { class: "bar-text" },
         link ? h("a", { href: link, class: "bar-label" }, shown) : h("span", { class: "bar-label" }, shown),
-        h("span", { class: "bar-value" }, extra ? [extra(e.key), " "] : null, format(e.count), h("span", { class: "muted" }, " · " + share.toFixed(share < 10 ? 1 : 0) + "%"))),
+        h("span", { class: "bar-value" }, extra ? [extra(e.key), " "] : null, format(e.count), showShare ? h("span", { class: "muted" }, " · " + share.toFixed(share < 10 ? 1 : 0) + "%") : null)),
       h("div", { class: "bar-track" }, h("div", { class: "bar-fill", style: { width: Math.max(0.5, (e.count / peak) * 100) + "%" } })));
   }));
 }

internal/web/static/assets/pages/account.js

@@ -1,8 +1,8 @@
 // Your account: password and API tokens.
-import { h, mount, table, time, modal, input, field, select, errorBox, toast, copyBox } from "../ui.js";
+import { h, mount, table, time, input, field, errorBox, toast } from "../ui.js";
-import { get, api, state, catalog, can } from "../api.js";
+import { get, api, state, catalog } from "../api.js";
 import { rerender } from "../app.js";
-import { revoke, rotateDialog } from "./users.js";
+import { revoke, rotateDialog, tokenDialog } from "./users.js";
 
 export async function render(el) {
   const me = state.me;
@@ -30,7 +30,7 @@ export async function render(el) {
     h("div", { class: "panel" },
       h("div", { class: "page-head" }, h("div", { class: "grow" }, h("h2", null, "API tokens"),
         h("div", { class: "muted" }, "For the hc CLI and scripts: 'hc config set token'.")),
-        h("button", { onclick: () => newToken(cat) }, "New token")),
+        h("button", { onclick: () => tokenDialog(cat) }, "New token")),
       table([
         { label: "Name", render: (t) => t.name },
         { label: "May", render: (t) => h("span", { class: "mono small" }, t.grant_strings.join(" ")) },
@@ -41,31 +41,3 @@ export async function render(el) {
           h("button", { class: "small reveal", onclick: () => revoke(t) }, "Revoke")] },
       ], tokens, { empty: "No tokens." })));
 }
-
-async function newToken(cat) {
-  const name = input({ placeholder: "laptop, backup script…" });
-  // Only roles within what the user may do: a token can never do more
-  // than its user, so offering more would only mislead.
-  const roles = Object.keys(cat.roles).filter((r) => cat.roles[r].every((g) => {
-    const [res, acc] = g.split(":");
-    return can(res, acc === "write");
-  }));
-  const role = select([["", "everything you may do"], ...roles.map((r) => [r, r + ": " + cat.roles[r].join(" ")])], "");
-  const expires = select([["", "never"], ["30d", "30 days"], ["90d", "90 days"], ["365d", "a year"]], "90d");
-  const err = h("div");
-  await modal("New API token", h("div", null, h("div", { class: "form-grid" }, field("Name", name), field("May do", role), field("Expires", expires)), err), [
-    { label: "Cancel", value: null },
-    { label: "Create", kind: "primary", onclick: async () => {
-      mount(err);
-      try {
-        const t = await api("POST", "/me/tokens", { body: { name: name.value.trim(), role: role.value || undefined, expires_in: expires.value || undefined } });
-        await modal("Token created", h("div", null, h("p", null, "Copy it now: it is not shown again."), copyBox(t.secret)));
-        rerender();
-        return true;
-      } catch (e) {
-        mount(err, errorBox(e));
-        return false;
-      }
-    } },
-  ]);
-}

internal/web/static/assets/pages/bans.js

@@ -0,0 +1,146 @@
+// Ban lists, and the addresses banned in them (docs/bans.md).
+import { h, mount, table, modal, errorBox, field, input, select, checkbox, confirmDialog, badge, toast, relTime } from "../ui.js";
+import { get, api, change, can } from "../api.js";
+import { rerender, onLeave } from "../app.js";
+import { listEditor, fmtSeconds, parseSeconds, rowClass, lookupNames, named, hits, counters } from "../widgets.js";
+
+const scopes = {
+  firewall: "the firewall itself",
+  hosts: "its hosts, behind the firewall",
+  everything: "the firewall and everything behind it",
+};
+
+export async function render(el) {
+  const config = can("config", false);
+  const write = can("config", true);
+  const lists = await get("/banlists");
+  const out = h("div");
+  const draw = async () => {
+    const [bans, cs] = await Promise.all([get("/bans"), counters()]);
+    const names = await lookupNames(bans.map((b) => b.address));
+    const count = {};
+    for (const b of bans) count[b.list_id] = (count[b.list_id] || 0) + 1;
+    mount(out,
+      h("h2", null, "Ban lists"),
+      h("div", { class: "panel" }, table([
+        { label: "Name", render: (l) => h("strong", null, l.name) },
+        { label: "Keeps banned addresses from", render: (l) => [scopes[l.scope] || l.scope, l.hosts && l.hosts.length ? h("span", { class: "mono small" }, ": " + l.hosts.join(", ")) : null] },
+        { label: "Never bans", render: (l) => h("span", { class: "mono small" }, (l.never || []).join(", ") || "–") },
+        { label: "Bans", render: (l) => String(count[l.id] || 0) },
+        { label: "Dropped", render: (l) => hits(cs, "ban" + l.id) },
+        { label: "Comment", render: (l) => l.comment },
+        write ? { label: "", tdClass: "actions-cell", render: (l) => l.pending === "deleted" ? badge("deleted", "err") : [
+          h("button", { class: "small reveal", onclick: () => listDialog(l) }, "Edit"), " ",
+          h("button", { class: "small reveal", onclick: () => del(l) }, "Delete")] } : null,
+      ].filter(Boolean), lists, { empty: "No ban lists yet.", rowClass })),
+      h("h2", null, "Banned addresses"),
+      h("div", { class: "panel" }, table([
+        { label: "Address", render: (b) => h("span", { class: "mono" }, named(names, b.address)) },
+        { label: "List", render: (b) => b.list },
+        { label: "Ports", render: (b) => b.protocol ? b.protocol + "/" + b.port : "all" },
+        { label: "Ends in", render: (b) => b.timeout ? fmtSeconds(b.timeout) : "never" },
+        { label: "Banned", render: (b) => relTime(b.created) },
+        { label: "By", render: (b) => [b.who, b.source ? h("span", { class: "muted small" }, " " + b.source) : null] },
+        { label: "Reason", render: (b) => h("span", { class: "small", title: b.reason || "" }, (b.reason || "").length > 80 ? b.reason.slice(0, 79) + "…" : b.reason || "") },
+        { label: "", tdClass: "actions-cell", render: (b) => mayBan() ? h("button", { class: "small reveal", onclick: () => unban(b, draw) }, "Unban") : null },
+      ], bans, { empty: "Nothing is banned." })));
+  };
+  mount(el,
+    h("div", { class: "page-head" },
+      h("div", { class: "grow" }, h("h1", null, "Bans"), h("div", { class: "muted" },
+        "Programs such as Guard and fail2ban ban addresses into a ban list; the list says what a banned address is kept from. Bans are dropped ahead of every rule, established connections too, and end by themselves.")),
+      h("div", { class: "actions" },
+        lists.length && mayBan() ? h("button", { onclick: () => banDialog(lists, draw) }, "Ban an address…") : null,
+        write ? h("button", { class: "primary", onclick: () => listDialog(null) }, "Add ban list") : null)),
+    config || lists.length ? out : h("div", { class: "empty" }, "No ban lists you may see."));
+  await draw();
+  const t = setInterval(() => { if (!document.hidden && !document.querySelector(".modal")) draw().catch(() => {}); }, 15000);
+  onLeave(() => clearInterval(t));
+}
+
+// mayBan: a bans:write grant may name its lists; the server checks.
+function mayBan() { return can("bans", true); }
+
+async function unban(b, draw) {
+  const what = b.address + (b.protocol ? " (" + b.protocol + "/" + b.port + ")" : "");
+  if (!await confirmDialog("Unban", "Lift the ban on " + what + " in " + b.list + "?", "Unban")) return;
+  try { await api("DELETE", "/banlists/" + encodeURIComponent(b.list) + "/bans/" + b.id); toast("Unbanned " + what); draw(); } catch (e) { toast(e.message, "err"); }
+}
+
+async function del(l) {
+  if (!await confirmDialog("Delete ban list", "Delete ban list " + l.name + "? Its bans are lifted, and programs banning into it are refused.", "Delete", "danger")) return;
+  try { await change("DELETE", "/banlists/" + l.id); rerender(); } catch (e) { modal("Not deleted", errorBox(e)); }
+}
+
+async function banDialog(lists, draw) {
+  const list = select(lists.map((l) => [l.name, l.name + " (" + l.scope + ")"]), lists[0].name);
+  const addr = input({ placeholder: "203.0.113.9 or 2001:db8::9", class: "mono" });
+  const proto = select([["", "every port"], ["tcp", "TCP"], ["udp", "UDP"]], "");
+  const ports = input({ placeholder: "22, ssh, http,https" });
+  const t = input({ placeholder: "the list's default", class: "short" });
+  const reason = input({ placeholder: "why, for the record" });
+  const err = h("div");
+  await modal("Ban an address", h("div", null, h("div", { class: "form-grid" },
+    field("Ban list", list), field("Address", addr, "An IPv6 address is banned with the list's grouping: its /64 unless the list says otherwise."),
+    field("Ports", h("div", { class: "filter-row" }, proto, ports), "Every port, or a protocol's ports (numbers or service names)."),
+    field("For", t, "1h, 1d; empty: the list's default."), field("Reason", reason)), err), [
+    { label: "Cancel", value: null },
+    { label: "Ban", kind: "danger", onclick: async () => {
+      mount(err);
+      const secs = parseSeconds(t.value);
+      if (secs === null) { mount(err, h("div", { class: "msg err" }, "Write the time as 1h, 30m or 1d.")); return false; }
+      if (proto.value && !ports.value.trim()) { mount(err, h("div", { class: "msg err" }, "Give the ports, or ban every port.")); return false; }
+      try {
+        const r = await api("POST", "/banlists/" + encodeURIComponent(list.value) + "/bans", { body: { address: addr.value.trim(), protocol: proto.value,
+          ports: proto.value ? ports.value.trim() : undefined, time: secs || 0, reason: reason.value.trim(), source: "web" } });
+        toast("Banned " + r.bans.map((b) => b.address + (b.protocol ? " " + b.protocol + "/" + b.port : "")).join(", ") + (r.closed ? "; " + r.closed + " connections closed" : ""));
+        draw();
+        return true;
+      } catch (e) { mount(err, errorBox(e)); return false; }
+    } },
+  ], { wide: true });
+}
+
+async function listDialog(l) {
+  l = l || { scope: "firewall", hosts: [], never: [] };
+  const name = input({ value: l.name || "", placeholder: "web", disabled: !!l.id });
+  const scope = select(Object.entries(scopes).map(([k, v]) => [k, k + ": " + v]), l.scope);
+  const hostsEd = listEditor(l.hosts || [], { placeholder: "10.0.10.57, 2001:db8:10::57, or a set", addLabel: "Add host" });
+  const never = listEditor(l.never || [], { placeholder: "198.51.100.0/24, or a set", addLabel: "Add address" });
+  const hostFields = field("Hosts", hostsEd, "The machines this list protects: their addresses, IPv4 and IPv6, or sets. Port forwards to them are covered too.").filter(Boolean);
+  const showHosts = () => { for (const n of hostFields) n.classList.toggle("hidden", scope.value !== "hosts"); };
+  scope.addEventListener("change", showHosts);
+  showHosts();
+  const time = input({ value: l.default_time ? fmtSeconds(l.default_time) : "", placeholder: "1h", class: "short" });
+  const maxTime = input({ value: l.max_time > 0 ? fmtSeconds(l.max_time) : "", placeholder: "7d", class: "short" });
+  const forever = checkbox("no limit: bans may last for ever", l.max_time < 0);
+  const entries = input({ value: l.max_entries || "", placeholder: "10000", class: "short", type: "number" });
+  const group = input({ value: l.group_v6 || "", placeholder: "64", class: "short", type: "number" });
+  const disabled = checkbox("disabled: the list's bans aren't in force", !!l.disabled);
+  const comment = input({ value: l.comment || "" });
+  const err = h("div");
+  await modal(l.id ? "Edit ban list " + l.name : "Add ban list", h("div", null, h("div", { class: "form-grid" },
+    field("Name", name, l.id ? "Programs and tokens know the list by its name, so it can't be changed." : "Programs ban into the list by this name; give each a token for it alone (bans:write:NAME)."),
+    field("Scope", scope, "What a banned address is kept from."), ...hostFields,
+    field("Never ban", never, "Besides what is never banned anyway: inside networks, the firewall's own addresses and whoever asks."),
+    field("Ban time", time, "A ban's length when the program asks for none."),
+    field("Longest ban", maxTime, "Longer bans are cut to this."), h("label"), forever,
+    field("Most bans", entries), field("IPv6 banned by", group, "Prefix length: 64 bans what one customer usually gets, 128 one address."),
+    h("label"), disabled, field("Comment", comment)), err), [
+    { label: "Cancel", value: null },
+    { label: l.id ? "Save" : "Add ban list", kind: "primary", onclick: async () => {
+      mount(err);
+      const t = parseSeconds(time.value), m = parseSeconds(maxTime.value);
+      if (t === null || m === null) { mount(err, h("div", { class: "msg err" }, "Write times as 1h, 30m or 7d.")); return false; }
+      const body = { scope: scope.value, hosts: scope.value === "hosts" ? hostsEd.value() : [], never: never.value(),
+        default_time: t || 0, max_time: forever.input.checked ? -1 : m || 0, max_entries: parseInt(entries.value, 10) || 0,
+        group_v6: parseInt(group.value, 10) || 0, disabled: disabled.input.checked, comment: comment.value.trim() };
+      if (!l.id) body.name = name.value.trim();
+      try {
+        await change(l.id ? "PATCH" : "POST", l.id ? "/banlists/" + l.id : "/banlists", body);
+        rerender();
+        return true;
+      } catch (e) { mount(err, errorBox(e)); return false; }
+    } },
+  ], { wide: true, sticky: true });
+}

internal/web/static/assets/pages/dashboard.js

@@ -3,7 +3,7 @@
 import { h, mount, table, badge, problemsList, time, plural } from "../ui.js";
 import { get, can } from "../api.js";
 import { onLeave } from "../app.js";
-import { describe, hits, humanCount, fmtBytes, usageBar, lookupNames, named } from "../widgets.js";
+import { describe, hits, humanCount, fmtBytes, usageBar, lookupNames, named, pct } from "../widgets.js";
 import { lineChart, chartCard, legend, timeTable, stepSeconds } from "../charts.js";
 import { bytes } from "./stats.js";
 
@@ -72,19 +72,26 @@ export async function render(el) {
 }
 
 // quotaPanel lists every rule's quota with what it used: the total, or
-// for a per-address quota the busiest address (the rest are on the rule).
+// for a per-address quota how many addresses used theirs up and the
+// busiest (the rest are on the rule). A per-address quota's bar is all
+// its addresses together, so one address alone can't fill it.
 function quotaPanel(quotas, names) {
   const perAddress = (q) => q.quota.per_source || q.quota.per_destination;
-  const used = (q) => perAddress(q) ? ((q.addresses || [])[0] || { used: 0 }).used : q.used;
+  const addrs = (q) => q.addresses || [];
+  const usedUp = (q) => addrs(q).filter((a) => a.used >= q.quota.bytes).length;
+  const bar = (q) => perAddress(q)
+    ? usageBar(addrs(q).reduce((n, a) => n + Math.min(a.used, q.quota.bytes), 0), addrs(q).length * q.quota.bytes)
+    : usageBar(q.used, q.quota.bytes);
   return h("div", { class: "panel" },
     h("div", { class: "panel-head" }, h("h2", null, "Quotas"), h("a", { class: "button small", href: "#/stats" }, "Statistics")),
     table([
       { label: "Rule", render: (q) => h("a", { href: "#/rules?rule=" + q.rule_id }, q.rule) },
       { label: "Allowance", render: (q) => fmtBytes(q.quota.bytes) + (q.quota.per_source ? " each source" : q.quota.per_destination ? " each destination" : "") },
       { label: "Used", render: (q) => perAddress(q)
-        ? [plural((q.addresses || []).length, "address", "addresses"), q.addresses && q.addresses.length ? [", busiest ", named(names, q.addresses[0].address), " " + fmtBytes(used(q))] : ""]
+        ? [plural(addrs(q).length, "address", "addresses"), usedUp(q) ? ", " + usedUp(q) + " used up" : "",
-        : fmtBytes(q.used) },
+          addrs(q).length ? [", busiest ", named(names, addrs(q)[0].address), " " + fmtBytes(addrs(q)[0].used) + " (" + pct(addrs(q)[0].used, q.quota.bytes) + ")"] : ""]
-      { label: "", render: (q) => usageBar(used(q), q.quota.bytes) },
+        : fmtBytes(q.used) + " (" + pct(q.used, q.quota.bytes) + ")" },
+      { label: "", render: (q) => addrs(q).length || !perAddress(q) ? bar(q) : "" },
       { label: "Next reset", render: (q) => q.next_reset ? time(q.next_reset) : h("span", { class: "muted" }, "by hand") },
     ], quotas));
 }

internal/web/static/assets/pages/history.js

@@ -1,5 +1,5 @@
 // History: every configuration change, with undo.
-import { h, mount, table, time, confirmDialog, modal, errorBox, badge } from "../ui.js";
+import { h, mount, table, time, confirmDialog, modal, errorBox, badge, diffView } from "../ui.js";
 import { get, change, can, state } from "../api.js";
 import { rerender } from "../app.js";
 
@@ -29,7 +29,7 @@ async function undo(e) {
 }
 
 async function entry(el, id) {
-  const e = await get("/history/" + id);
+  const [e, d] = await Promise.all([get("/history/" + id), get("/history/" + id + "/diff").catch(() => null)]);
   mount(el,
     h("nav", { class: "back-link" }, h("a", { href: "#/history" }, "← History")),
     h("div", { class: "page-head" },
@@ -40,7 +40,11 @@ async function entry(el, id) {
       can("config", true) && !e.reverted_by ? h("div", { class: "actions" }, h("button", { onclick: () => undo(e) }, "Undo")) : null),
     e.changes.map((c) => h("div", { class: "panel" },
       h("h3", null, action(c) + " " + c.kind + " ", h("span", { class: "mono" }, c.label)),
-      fieldsTable(c))));
+      fieldsTable(c))),
+    d ? h("div", { class: "panel" },
+      h("h3", null, "Ruleset"),
+      h("p", { class: "muted small" }, "What this change did to the ruleset, rendered by this version of Housecarl."),
+      diffView(d.diff)) : null);
 }
 
 function action(c) {
@@ -50,9 +54,10 @@ function action(c) {
 }
 
 // fieldsTable lists the fields that differ (all of them for a create or
-// delete).
+// delete). An object within (settings' builtins) is listed by its own
+// fields, "builtins.drop_invalid", so only what changed shows.
 function fieldsTable(c) {
-  const a = c.before || {}, b = c.after || {};
+  const a = flatten(c.before || {}), b = flatten(c.after || {});
   const keys = [...new Set([...Object.keys(a), ...Object.keys(b)])].sort();
   const show = (v, k) => {
     if (v === undefined || v === "") return "–";
@@ -68,3 +73,14 @@ function fieldsTable(c) {
     c.after ? { label: c.before ? "After" : "Value", render: (k) => h("span", { class: "mono small" }, show(b[k], k)) } : null,
   ].filter(Boolean), rows);
 }
+
+// flatten lifts the fields of objects within an object to dotted keys
+// ({builtins: {loopback: true}} → {"builtins.loopback": true}); lists
+// stay whole.
+function flatten(o, prefix = "", out = {}) {
+  for (const [k, v] of Object.entries(o)) {
+    if (v && typeof v === "object" && !Array.isArray(v) && Object.keys(v).length) flatten(v, prefix + k + ".", out);
+    else out[prefix + k] = v;
+  }
+  return out;
+}

internal/web/static/assets/pages/rules.js

@@ -2,7 +2,7 @@
 import { h, mount, table, modal, errorBox, field, input, select, checkbox, confirmDialog, badge, textarea, toast } from "../ui.js";
 import { get, api, change, can } from "../api.js";
 import { rerender } from "../app.js";
-import { names, matchEditor, describe, hits, counters, listEditor, rowClass, live, fmtBytes, quotas, usageBar, lookupNames, named } from "../widgets.js";
+import { names, matchEditor, describe, hits, counters, listEditor, rowClass, live, fmtBytes, quotas, usageBar, lookupNames, named, pct } from "../widgets.js";
 
 const chains = [
   ["input", "Input", "Traffic to the firewall itself."],
@@ -62,6 +62,7 @@ export async function render(el, params, query) {
           return [
           h("button", { class: "small reveal", title: "Move up", disabled: i === 0, onclick: () => move(r, { before: rs[i - 1].id }) }, "↑"), " ",
           h("button", { class: "small reveal", title: "Move down", disabled: i === rs.length - 1, onclick: () => move(r, { after: rs[i + 1].id }) }, "↓"), " ",
+          h("button", { class: "small reveal", title: "Move to another place, in one change", disabled: rs.length < 2, onclick: () => moveDialog(r, rs, (x) => live(rules).indexOf(x) + 1) }, "Move…"), " ",
           h("button", { class: "small reveal", onclick: () => ruleDialog(r, chain) }, "Edit"), " ",
           h("button", { class: "small reveal", onclick: () => toggle(r) }, r.disabled ? "Enable" : "Disable"), " ",
           h("button", { class: "small reveal", onclick: () => del(r) }, "Delete"),
@@ -165,10 +166,11 @@ function quotaLine(r, q) {
   const each = qt.per_source ? " each source" : qt.per_destination ? " each destination" : "";
   const resets = qt.reset === "monthly" ? "monthly" : qt.reset || "reset by hand";
   let used = fmtBytes(qt.bytes) + each;
-  if (q && !each) used = fmtBytes(q.used) + " of " + fmtBytes(qt.bytes) + " used";
+  if (q && !each) used = fmtBytes(q.used) + " of " + fmtBytes(qt.bytes) + " used (" + pct(q.used, qt.bytes) + ")";
   else if (q) {
-    const n = (q.addresses || []).length;
+    const a = q.addresses || [], n = a.length;
-    used += " · " + (n === 1 ? "1 address" : n + " addresses") + (n ? ", busiest " + fmtBytes(q.addresses[0].used) : "");
+    const up = a.filter((x) => x.used >= qt.bytes).length;
+    used += " · " + (n === 1 ? "1 address" : n + " addresses") + (up ? ", " + up + " used up" : "") + (n ? ", busiest " + fmtBytes(a[0].used) + " (" + pct(a[0].used, qt.bytes) + ")" : "");
   }
   const text = "quota " + used + " · " + resets;
   return h("div", { class: "muted small" }, q && r.pending !== "new"
@@ -193,12 +195,13 @@ async function quotaDialog(r, q) {
     perAddress ? table([
       { label: "Address", render: (a) => h("span", { class: "mono" }, named(names, a.address)) },
       { label: "Used", render: (a) => fmtBytes(a.used) },
+      { label: "", class: "num", tdClass: "num", render: (a) => pct(a.used, qt.bytes) },
       { label: "", render: (a) => usageBar(a.used, qt.bytes) },
       write ? { label: "", render: (a) => h("span", { class: "nowrap" },
         h("button", { class: "small", onclick: then(() => resetQuota(r, a.address)) }, "Reset"), " ",
         h("button", { class: "small", onclick: then(() => giveBack(r, a.address)) }, "Give back…")) } : null,
     ].filter(Boolean), q.addresses || [], { empty: "No address has used it since the last reset." })
-      : h("div", null, h("strong", null, fmtBytes(q.used)), " of " + fmtBytes(qt.bytes) + " used", usageBar(q.used, qt.bytes))),
+      : h("div", null, h("strong", null, fmtBytes(q.used)), " of " + fmtBytes(qt.bytes) + " used (" + pct(q.used, qt.bytes) + ")", usageBar(q.used, qt.bytes))),
   [
     ...(write ? [{ label: perAddress ? "Reset all" : "Reset", value: "reset" }, { label: perAddress ? "Give back to all…" : "Give back…", value: "give" }] : []),
     { label: "Close", value: null },
@@ -243,6 +246,28 @@ async function move(r, where) {
   try { await change("POST", "/rules/" + r.id + "/move", where, { quiet: true }); rerender(); } catch (e) { modal("Not moved", errorBox(e)); }
 }
 
+// moveDialog puts a rule anywhere among rs (the rules it can move
+// among) in one move: one change, or one staged operation.
+async function moveDialog(r, rs, order) {
+  const others = rs.filter((x) => x !== r);
+  const label = (x) => order(x) + ". " + (x.comment || (x.raw ? x.raw : describe(x))) + " (#" + x.id + ")";
+  const next = rs[rs.indexOf(r) + 1];
+  const where = select([...others.map((x) => [String(x.id), "before " + label(x)]), ["end", "after " + label(others[others.length - 1])]],
+    next ? String(next.id) : "end");
+  const err = h("div");
+  await modal("Move " + (r.comment || "rule #" + r.id), h("div", null, h("div", { class: "form-grid" }, field("Put it", where)), err), [
+    { label: "Cancel", value: null },
+    { label: "Move", kind: "primary", onclick: async () => {
+      const v = where.value;
+      if (v === (next ? String(next.id) : "end")) return true; // where it is
+      try {
+        await change("POST", "/rules/" + r.id + "/move", v === "end" ? { after: others[others.length - 1].id } : { before: Number(v) }, { quiet: true });
+        rerender();
+      } catch (e) { mount(err, errorBox(e)); return false; }
+    } },
+  ]);
+}
+
 async function toggle(r) {
   try { await change("PATCH", "/rules/" + r.id, { disabled: !r.disabled }); rerender(); } catch (e) { modal("Not changed", errorBox(e)); }
 }
@@ -258,6 +283,9 @@ export async function ruleDialog(r, chain) {
   r = r || { chain, action: "accept" };
   const ch = select(["input", "forward", "output", "early"], r.chain || chain);
   const match = matchEditor(r, n);
+  const chainZones = () => match.zones(ch.value !== "output", ch.value === "forward" || ch.value === "output");
+  ch.addEventListener("change", chainZones);
+  chainZones();
   const action = select([["accept", "accept"], ["drop", "drop"], ["reject", "reject"], ["log", "log only (and go on)"]], r.action);
   const rejectWith = select([["", "with an ICMP error"], ["tcp-reset", "with a TCP reset (TCP rules only)"]], r.reject_with || "");
   const every = checkbox("every packet: also stop connections already open, not just new ones", r.every_packet);
@@ -369,6 +397,7 @@ export async function ruleDialog(r, chain) {
   const addersLabel = h("label");
   sections.raw.onShow = (on) => {
     for (const n of [...matchNodes, ...actionField, ...logField]) n.classList.toggle("hidden", on);
+    if (!on) chainZones();
     for (const [k, sec] of Object.entries(sections)) {
       if (k === "raw") continue;
       if (on && sec.open) for (const n of sec.nodes) n.classList.add("hidden");

internal/web/static/assets/pages/sets.js

@@ -1,5 +1,5 @@
-// Address sets, and dynamic sets' entries.
+// Address sets, dynamic sets' entries, and what Jarl sets hold.
-import { h, mount, table, modal, errorBox, field, input, checkbox, confirmDialog, badge, toast } from "../ui.js";
+import { h, mount, table, modal, errorBox, field, input, select, confirmDialog, badge, toast, fmtTime } from "../ui.js";
 import { get, api, change, can } from "../api.js";
 import { rerender } from "../app.js";
 import { listEditor, fmtSeconds, parseSeconds, rowClass } from "../widgets.js";
@@ -9,11 +9,14 @@ export async function render(el) {
   const write = can("config", true);
   mount(el,
     h("div", { class: "page-head" },
-      h("div", { class: "grow" }, h("h1", null, "Address sets"), h("div", { class: "muted" }, "Named lists of IPv4 and IPv6 addresses, prefixes and ranges, mixed. A dynamic set takes entries at run time, each with a timeout (a captive portal's signed-in clients).")),
+      h("div", { class: "grow" }, h("h1", null, "Address sets"), h("div", { class: "muted" }, "Named lists of IPv4 and IPv6 addresses, prefixes and ranges, mixed. A dynamic set takes entries at run time, each with a timeout (a captive portal's signed-in clients). A Jarl set holds the addresses of names in Jarl, kept up to date.")),
       write ? h("div", { class: "actions" }, h("button", { class: "primary", onclick: () => setDialog(null) }, "Add set")) : null),
     h("div", { class: "panel" }, table([
       { label: "Name", render: (s) => h("strong", null, s.name) },
-      { label: "Entries", render: (s) => s.dynamic ? [badge("dynamic", "accent"), s.timeout ? " timeout " + fmtSeconds(s.timeout) : "", " ",
+      { label: "Entries", render: (s) => s.jarl ? [badge("Jarl", "accent"), " ", h("span", { class: "mono small" }, jarlNames(s).join(", ")),
+        h("span", { class: "muted small" }, " within " + s.jarl.within.join(", ")), " ",
+        s.pending ? null : h("button", { class: "small", onclick: () => jarlStatus(s) }, "Addresses…")]
+        : s.dynamic ? [badge("dynamic", "accent"), s.timeout ? " timeout " + fmtSeconds(s.timeout) : "", " ",
         s.pending ? null : h("button", { class: "small", onclick: () => entries(s) }, "Entries…")] : h("span", { class: "mono small" }, s.entries.join(", ")) },
       { label: "Comment", render: (s) => s.comment },
       write ? { label: "", tdClass: "actions-cell", render: (s) => s.pending === "deleted" ? badge("deleted", "err") : [
@@ -27,33 +30,52 @@ async function del(s) {
   try { await change("DELETE", "/sets/" + s.id); rerender(); } catch (e) { modal("Not deleted", errorBox(e)); }
 }
 
+const nameOf = (n) => n.view ? n.name + "@" + n.view : n.name;
+const jarlNames = (s) => (s.jarl.names || []).map(nameOf);
+
+// parseJarlName reads "name" or "name@view".
+function parseJarlName(v) {
+  const i = v.indexOf("@");
+  return i < 0 ? { name: v } : { name: v.slice(0, i), view: v.slice(i + 1) };
+}
+
 async function setDialog(s) {
   s = s || { entries: [] };
+  const zones = (await get("/zones")).map((z) => z.name);
   const name = input({ value: s.name || "", placeholder: "trusted" });
   const list = listEditor(s.entries, { placeholder: "192.168.1.0/24, 2001:db8:1::/64, 192.168.1.100-192.168.1.199", addLabel: "Add entry" });
-  const dynamic = checkbox("dynamic: entries are added at run time (the Entries button, hc set entries, a program with a token), each for a time", s.dynamic);
+  const kind = select([["list", "addresses listed here"], ["dynamic", "dynamic: entries added at run time, each for a time"], ["jarl", "from Jarl: the addresses of names in Jarl"]],
-  // A dynamic set has no configured entries; only it has a timeout.
+    s.jarl ? "jarl" : s.dynamic ? "dynamic" : "list");
+  const names = listEditor(s.jarl ? jarlNames(s) : [], { placeholder: "nas.example.com@internal", addLabel: "Add name" });
+  const within = listEditor(s.jarl ? s.jarl.within : [], { placeholder: "lan, or 10.10.0.0/24", addLabel: "Add zone or network", suggestions: zones });
+  const timeout = input({ value: s.timeout ? fmtSeconds(s.timeout) : "", placeholder: "1h, 1d (none: until removed)", class: "short" });
+  // Each kind shows its own fields.
   const entryFields = field("Entries", list).filter(Boolean);
   const timeoutFields = field("Entry timeout", timeout, "How long an entry stays unless it is added with its own. Empty: until removed (or a reboot).").filter(Boolean);
+  const jarlFields = [
+    ...field("Names in Jarl", names, "The set holds their A and AAAA records' addresses (all of them), CNAMEs followed. Write NAME@VIEW, or just NAME if only one of Jarl's views has it. Read again every minute.").filter(Boolean),
+    ...field("Within", within, "Where its addresses may be: zones (the networks connected to their interfaces) or networks. An address elsewhere is left out, so a changed record in Jarl can't let anything else in.").filter(Boolean),
+  ];
   const showKind = () => {
-    for (const n of entryFields) n.classList.toggle("hidden", dynamic.input.checked);
+    for (const n of entryFields) n.classList.toggle("hidden", kind.value !== "list");
-    for (const n of timeoutFields) n.classList.toggle("hidden", !dynamic.input.checked);
+    for (const n of timeoutFields) n.classList.toggle("hidden", kind.value !== "dynamic");
+    for (const n of jarlFields) n.classList.toggle("hidden", kind.value !== "jarl");
   };
-  dynamic.input.addEventListener("change", showKind);
+  kind.addEventListener("change", showKind);
   showKind();
-  const timeout = input({ value: s.timeout ? fmtSeconds(s.timeout) : "", placeholder: "1h, 1d (none: until removed)", class: "short" });
   const comment = input({ value: s.comment || "" });
   const err = h("div");
   await modal(s.id ? "Edit set " + s.name : "Add set", h("div", null, h("div", { class: "form-grid" },
-    field("Name", name), ...entryFields, h("label"), dynamic, ...timeoutFields, field("Comment", comment)), err), [
+    field("Name", name), ...field("Kind", kind), ...entryFields, ...timeoutFields, ...jarlFields, field("Comment", comment)), err), [
     { label: "Cancel", value: null },
     { label: s.id ? "Save" : "Add set", kind: "primary", onclick: async () => {
       mount(err);
       const t = parseSeconds(timeout.value);
       if (t === null) { mount(err, h("div", { class: "msg err" }, "Write the timeout as 1h, 30m or 1d.")); return false; }
+      const k = kind.value;
       try {
-        await change(s.id ? "PATCH" : "POST", s.id ? "/sets/" + s.id : "/sets", { name: name.value.trim(), entries: dynamic.input.checked ? [] : list.value(), dynamic: dynamic.input.checked,
+        await change(s.id ? "PATCH" : "POST", s.id ? "/sets/" + s.id : "/sets", { name: name.value.trim(), entries: k === "list" ? list.value() : [], dynamic: k === "dynamic",
-          timeout: dynamic.input.checked ? t : 0, comment: comment.value.trim() });
+          timeout: k === "dynamic" ? t : 0, jarl: k === "jarl" ? { names: names.value().map(parseJarlName), within: within.value() } : null, comment: comment.value.trim() });
         rerender();
         return true;
       } catch (e) { mount(err, errorBox(e)); return false; }
@@ -61,6 +83,44 @@ async function setDialog(s) {
   ], { wide: true, sticky: true });
 }
 
+// jarlStatus shows what a Jarl set holds: each name's addresses in Jarl,
+// used or left out (and why).
+async function jarlStatus(s) {
+  const body = h("div");
+  const path = "/sets/" + encodeURIComponent(s.name) + "/jarl";
+  const draw = (js) => {
+    const rows = [];
+    for (const n of js.names) {
+      // A new node for each row: a node can only be in one place.
+      const label = () => [h("span", { class: "mono" }, n.name), n.chain && n.chain.length ? h("span", { class: "muted small" }, " → " + n.chain.join(" → ")) : null];
+      const view = n.view || n.found_view || "";
+      if (n.problem) rows.push({ label, view, address: "", used: h("span", null, badge("no addresses", "err"), " " + n.problem) });
+      else if (!n.addresses.length) rows.push({ label, view, address: "", used: n.error ? "not read: " + n.error : "not read yet" });
+      for (const a of n.addresses) rows.push({ label, view, address: a.address, used: a.used ? badge("used", "ok") : h("span", null, badge("left out", "warn"), " " + a.why) });
+      if (n.error && n.addresses.length) rows.push({ label, view, address: "", used: h("span", { class: "muted" }, "The last read failed (" + n.error + "): these are from " + (n.checked ? fmtTime(n.checked) : "before") + ".") });
+    }
+    mount(body,
+      !js.configured ? h("div", { class: "msg warn" }, "Jarl isn't configured (jarl.server in housecarl.yaml): the set keeps the addresses it last had.") : null,
+      js.error ? h("div", { class: "msg warn" }, "Reading Jarl failed: " + js.error + ". The set keeps the addresses it had.") : null,
+      h("p", null, "Holds ", h("span", { class: "mono" }, js.entries.length ? js.entries.join(", ") : "nothing"), " · within " + js.within.join(", "),
+        js.read ? h("span", { class: "muted" }, " · Jarl read " + fmtTime(js.read)) : null),
+      table([
+        { label: "Name", render: (r) => r.label() },
+        { label: "View", render: (r) => r.view },
+        { label: "Address", render: (r) => h("span", { class: "mono" }, r.address) },
+        { label: "", render: (r) => r.used },
+      ], rows, { empty: "No names." }));
+  };
+  draw(await get(path));
+  await modal("Addresses of " + s.name, body, [
+    { label: "Read Jarl now", onclick: async () => {
+      try { draw(await api("POST", path + "/refresh")); } catch (x) { toast(x.message, "err"); }
+      return false;
+    } },
+    { label: "Close", value: null },
+  ], { wide: true });
+}
+
 // entries shows and changes a dynamic set's entries.
 async function entries(s) {
   const body = h("div");

internal/web/static/assets/pages/settings.js

@@ -54,7 +54,7 @@ export async function render(el) {
       field("Built-ins", h("div", { class: "checks" }, bis.map(([, c]) => c))),
       field("Your prefixes", own, "Your public prefixes (your delegated IPv6 /48): they can't come from outside."),
       field("Antispoof IPv4", v4),
-      field("Antispoof IPv6", v6),
+      field("Antispoof IPv6", v6, "Never link-local (fe80::/10): your ISP's router adverts and DHCPv6 replies come from it."),
       field("Flowtable", flow, "Forwarded TCP and UDP between these devices skip the rules once established (fast path): for a CPU that can't keep up with the line. Forward quotas, byte rates and traffic per device then only count first packets (docs/flowtable.md). Exact names, both sides (wan and lan); none: off."),
       field("Probation", probation, "How long a change made over the network has to be confirmed before it is rolled back."),
       h("label"), manual,

internal/web/static/assets/pages/stats.js

@@ -98,13 +98,14 @@ export async function render(el, params, query) {
     ? "No traffic per device " + rangeLabel + "."
     : ["Traffic per device is off. Turn it on under ", h("a", { href: "#/settings" }, "Settings"), " (it adds a counter for each inside address)."]);
   parts.push(h("div", { class: "chart-grid" },
-    listCard("Busiest rules", "packets each counted, " + rangeLabel, barList(s.rules, { label: (k) => k, href: (k) => ruleHref(k) })),
+    listCard("Busiest rules", "packets each counted, " + rangeLabel, barList(s.rules, { label: (k) => k, href: (k) => ruleHref(k), empty: "No rule counted anything " + rangeLabel + "." })),
+    listCard("Built-ins and policies", "packets each counted; 'established' passes the replies and the rest of every allowed connection", barList(s.builtins || [], { label: (k) => k, href: (k) => ruleHref(k) })),
     listCard("Dropped, by chain", "early: antispoofing · invalid: packets conntrack can't place", barList(s.drops_by_chain, { empty: "Nothing dropped " + rangeLabel + "." })),
     listCard("Blocked most", "sources of logged drops (the policies' with 'log drops' on, and rules that log)", barList(s.blocked_sources, { empty: "No logged drops " + rangeLabel + ".", href: (k) => "#/trace?address=" + encodeURIComponent(k) })),
     listCard("What they tried", "the logged drops' protocol and port", barList(s.blocked_ports, { empty: "No logged drops " + rangeLabel + "." })),
     listCard("Devices, received", "bytes from external zones, by inside address (IPv6 per /64)", s.devices_down.length ? barList(s.devices_down, { format: bytes, href: connHref }) : devHint),
     listCard("Devices, sent", "bytes to external zones", s.devices_up.length ? barList(s.devices_up, { format: bytes, href: connHref }) : devHint.cloneNode(true)),
-    d.quotas.length ? listCard("Quotas", "bytes counted against each rule's quota, " + rangeLabel, barList(d.quotas, { format: bytes, label: (k) => "rule #" + k.slice(1), href: () => "#/rules" })) : null,
+    d.quotas.length ? listCard("Quotas", "bytes counted against each rule's quota, " + rangeLabel, barList(d.quotas, { format: bytes, label: (k) => (d.hits.find((x) => x.key === k) || {}).name || "rule #" + k.slice(1), href: ruleHref, share: false })) : null,
     listCard("Rules that matched nothing", "in the last 30 days (or since statistics started): candidates to remove",
       unused.length ? h("div", null, h("ul", { class: "plain-list" }, unused.slice(0, 12).map((e) => h("li", null, h("a", { href: ruleHref(e.key) }, e.name || e.key)))),
         unused.length > 12 ? h("div", { class: "muted small" }, "and " + (unused.length - 12) + " more: hc stats rules --unused") : null) : h("div", { class: "empty" }, "Every rule matched something."))));

internal/web/static/assets/pages/users.js

@@ -1,6 +1,6 @@
 // Users and everyone's tokens (administrators).
 import { h, mount, table, time, fmtTime, modal, input, field, checkbox, select, errorBox, confirmDialog, toast, badge, copyBox } from "../ui.js";
-import { get, api, catalog } from "../api.js";
+import { get, api, catalog, can } from "../api.js";
 import { rerender } from "../app.js";
 
 export async function render(el) {
@@ -16,6 +16,7 @@ export async function render(el) {
       { label: "Last login", render: (u) => u.last_login_at ? time(u.last_login_at) : "never" },
       { label: "Comment", render: (u) => u.comment },
       { label: "", tdClass: "actions-cell", render: (u) => [
+        h("button", { class: "small reveal", onclick: () => tokenDialog(cat, u) }, "New token"), " ",
         h("button", { class: "small reveal", onclick: () => userDialog(u, cat) }, "Edit"), " ",
         h("button", { class: "small reveal", onclick: () => del(u) }, "Delete")] },
     ], users)),
@@ -32,6 +33,42 @@ export async function render(el) {
     ], tokens, { empty: "No tokens." })));
 }
 
+// tokenDialog makes an API token: the viewer's own, or (administrators)
+// another user's. It shows the secret once.
+export async function tokenDialog(cat, user) {
+  const name = input({ placeholder: "laptop, backup script…" });
+  // Only roles within what the user may do: a token can never do more
+  // than its user, so offering more would only mislead.
+  const may = (res, write) => {
+    if (!user) return can(res, write);
+    if (user.admin) return true;
+    const gs = user.grant_strings || [];
+    return gs.includes(res + ":write") || !write && gs.includes(res + ":read");
+  };
+  const roles = Object.keys(cat.roles).filter((r) => cat.roles[r].every((g) => {
+    const [res, acc] = g.split(":");
+    return may(res, acc === "write");
+  }));
+  const role = select([["", user ? "everything " + user.username + " may do" : "everything you may do"], ...roles.map((r) => [r, r + ": " + cat.roles[r].join(" ")])], "");
+  const expires = select([["", "never"], ["30d", "30 days"], ["90d", "90 days"], ["365d", "a year"]], "90d");
+  const err = h("div");
+  await modal(user ? "New API token for " + user.username : "New API token", h("div", null, h("div", { class: "form-grid" }, field("Name", name), field("May do", role), field("Expires", expires)), err), [
+    { label: "Cancel", value: null },
+    { label: "Create", kind: "primary", onclick: async () => {
+      mount(err);
+      try {
+        const t = await api("POST", user ? "/users/" + user.id + "/tokens" : "/me/tokens", { body: { name: name.value.trim(), role: role.value || undefined, expires_in: expires.value || undefined } });
+        await modal("Token created", h("div", null, h("p", null, "Copy it now: it is not shown again." + (user ? " Give it to " + user.username + "; 'hc config set token' sets it in the CLI." : "")), copyBox(t.secret)));
+        rerender();
+        return true;
+      } catch (e) {
+        mount(err, errorBox(e));
+        return false;
+      }
+    } },
+  ]);
+}
+
 // rotateDialog gives a token a new secret. It keeps its name, ID and
 // permissions; only the programs that use it need the new secret.
 export async function rotateDialog(t) {

internal/web/static/assets/style.css

@@ -379,6 +379,10 @@ pre.wrap { white-space: pre-wrap; word-break: break-all; font-size: 12px; }
 .list-rows { display: flex; flex-direction: column; gap: 6px; margin-bottom: 6px; }
 .list-row { display: flex; gap: 6px; align-items: center; }
 .list-row input { width: 26em; max-width: 100%; }
+.negatable { display: flex; gap: 8px; align-items: flex-start; flex-wrap: wrap; }
+.negatable > .list-editor { flex: 1; min-width: 0; }
+.negatable.negated > select { color: var(--err); border-color: var(--err); font-weight: 600; }
+.negatable.negated .list-rows { border-left: 3px solid var(--err); padding-left: 8px; }
 input.short { width: 7em; }
 .builtins { margin-bottom: 10px; line-height: 1.6; }
 .policy { margin-top: 10px; }
@@ -409,6 +413,7 @@ input.wide { width: 100%; }
 .diff .add { background: var(--add); color: var(--add-text); }
 .diff .del { background: var(--del); color: var(--del-text); }
 .diff .hunk { background: var(--hunk); color: var(--accent); }
+.diff .hunk .block { font-weight: 700; color: var(--text); }
 .diff .file { font-weight: 700; padding-top: 6px; }
 select.inline { width: auto; display: inline-block; }
 /* The rule dialog's optional parts: "+" buttons, and ✕ to close one. */

internal/web/static/assets/ui.js

@@ -200,7 +200,12 @@ export function diffView(text) {
     if (line.startsWith("+++") || line.startsWith("---")) cls = "file";
     else if (line.startsWith("+")) cls = "add";
     else if (line.startsWith("-")) cls = "del";
-    else if (line.startsWith("@@")) cls = "hunk";
+    else if (line.startsWith("@@")) {
+      // "@@ -a,b +c,d @@ chain forward": the chain the hunk is in.
+      const m = line.match(/^(@@ .*? @@)(?: (.+))?$/);
+      box.append(h("div", { class: "hunk" }, m ? [m[1], m[2] ? [" ", h("span", { class: "block" }, m[2])] : null] : line));
+      continue;
+    }
     box.append(h("div", { class: cls }, line || " "));
   }
   return box;

internal/web/static/assets/widgets.js

@@ -1,6 +1,6 @@
 // Widgets shared by several pages: list editors with suggestions, the
 // match editor of rules and NAT, descriptions, hit counts, durations.
-import { h, input, select, field, checkbox } from "./ui.js";
+import { h, input, select, field } from "./ui.js";
 import { get, api } from "./api.js";
 
 // ---- durations
@@ -65,33 +65,60 @@ export function listEditor(values, opts = {}) {
 
 // ---- matches
 
+// negatable puts "any of" / "any but" in front of a list editor, so a
+// field says first whether it matches its entries or everything else;
+// "any but" marks the list. The choice shows once the list has a row
+// (empty is "any"), and an empty list is never negated. value() is the
+// list, negated() the choice.
+function negatable(list, not) {
+  const mode = select([["", "any of"], ["not", "any but"]], not ? "not" : "", { class: "inline" });
+  const box = h("div", { class: "negatable" }, mode, list);
+  const rows = () => list.querySelector(".list-rows").children.length;
+  const update = () => {
+    mode.classList.toggle("hidden", rows() === 0);
+    box.classList.toggle("negated", mode.value === "not" && rows() > 0);
+  };
+  mode.addEventListener("change", update);
+  // Add and remove act on their own click first; this runs after.
+  list.addEventListener("click", update);
+  update();
+  box.value = list.value;
+  box.negated = () => mode.value === "not" && list.value().length > 0;
+  return box;
+}
+
 // matchEditor edits what a rule, source NAT or redirect matches. It
 // returns the form-grid fields; value() is the match's fields.
 export function matchEditor(m, n, opts = {}) {
   m = m || {};
   const zones = (list) => listEditor(list, { suggestions: n.zones, placeholder: "zone", mono: false, addLabel: "Add zone" });
   const addrs = (list) => listEditor(list, { suggestions: n.sets, placeholder: "a set, 192.168.1.0/24, 2001:db8:1::/64, 192.168.1.100-192.168.1.199", addLabel: "Add" });
-  const inZ = zones(m.in_zones), outZ = zones(m.out_zones);
+  const inZ = negatable(zones(m.in_zones), m.not_in), outZ = negatable(zones(m.out_zones), m.not_out);
-  const notIn = checkbox("any zone but these", m.not_in), notOut = checkbox("any zone but these", m.not_out);
+  const src = negatable(addrs(m.sources), m.not_sources), dst = negatable(addrs(m.destinations), m.not_destinations);
-  const src = addrs(m.sources), dst = addrs(m.destinations);
-  const notSrc = checkbox("any source but these", m.not_sources), notDst = checkbox("any destination but these", m.not_destinations);
   const svc = listEditor(m.services, { suggestions: n.services, placeholder: "ssh, https, tcp/8080, udp/1000-2000, icmp/echo-request", addLabel: "Add service" });
   const fam = select([["", "IPv4 and IPv6"], ["ipv4", "IPv4 only"], ["ipv6", "IPv6 only"]], m.family || "");
+  const inField = opts.in !== false ? field("Coming in on", inZ) : null;
+  const outField = opts.out !== false ? field("Going out on", outZ) : null;
   const fields = [
-    opts.in !== false ? field("Coming in on", h("div", null, inZ, notIn)) : null,
+    inField,
-    opts.out !== false ? field("Going out on", h("div", null, outZ, notOut)) : null,
+    outField,
-    field("From", h("div", null, src, notSrc), "Sets, addresses, prefixes or ranges, IPv4 and IPv6 mixed. Empty: any."),
+    field("From", src, "Sets, addresses, prefixes or ranges, IPv4 and IPv6 mixed. Empty: any."),
-    field("To", h("div", null, dst, notDst)),
+    field("To", dst),
     field("Services", svc, "Named services (built in, or yours) or entries such as tcp/8080. Empty: any traffic."),
     field("Family", fam),
   ];
   fields.value = () => {
-    const v = { sources: src.value(), not_sources: notSrc.input.checked, destinations: dst.value(), not_destinations: notDst.input.checked,
+    const v = { sources: src.value(), not_sources: src.negated(), destinations: dst.value(), not_destinations: dst.negated(),
       services: svc.value(), family: fam.value };
-    if (opts.in !== false) Object.assign(v, { in_zones: inZ.value(), not_in: notIn.input.checked });
+    // A hidden zone field (the chain has no such interface) matches nothing.
-    if (opts.out !== false) Object.assign(v, { out_zones: outZ.value(), not_out: notOut.input.checked });
+    if (inField) Object.assign(v, inField[1].classList.contains("hidden") ? { in_zones: [], not_in: false } : { in_zones: inZ.value(), not_in: inZ.negated() });
+    if (outField) Object.assign(v, outField[1].classList.contains("hidden") ? { out_zones: [], not_out: false } : { out_zones: outZ.value(), not_out: outZ.negated() });
     return v;
   };
+  // zones shows the zone fields a chain can use: input and early have no
+  // outgoing interface, output no incoming one.
+  const show = (f, on) => f && f.filter(Boolean).forEach((e) => e.classList.toggle("hidden", !on));
+  fields.zones = (inOn, outOn) => { show(inField, inOn); show(outField, outOn); };
   return fields;
 }
 
@@ -161,6 +188,13 @@ export function fmtBytes(n) {
   return n + " bytes";
 }
 
+// pct writes used as a share of total: "25%", "<1%" for a little.
+export function pct(used, total) {
+  if (!total || used <= 0) return "0%";
+  const p = used / total * 100;
+  return p < 1 ? "<1%" : Math.floor(p) + "%";
+}
+
 // usageBar draws used out of total as a bar, red once it is all used.
 export function usageBar(used, total) {
   const seg = h("div", { class: "seg leased" });

scripts/e2e.sh

@@ -20,7 +20,8 @@ IMAGE=${E2E_IMAGE:-housecarl-nft}
 WORK=${WORK:-$(mktemp -d "${TMPDIR:-/tmp}/housecarl-e2e.XXXXXX")}
 docker info >/dev/null 2>&1 || { echo "Docker isn't reachable (set DOCKER_HOST?)"; exit 2; }
 
-(cd "$ROOT" && CGO_ENABLED=0 go build -o "$WORK/housecarld" ./cmd/housecarld && CGO_ENABLED=0 go build -o "$WORK/hc" ./cmd/hc) || exit 1
+(cd "$ROOT" && CGO_ENABLED=0 go build -o "$WORK/housecarld" ./cmd/housecarld && CGO_ENABLED=0 go build -o "$WORK/hc" ./cmd/hc &&
+	CGO_ENABLED=0 go build -o "$WORK/fakejarl" ./scripts/fakejarl) || exit 1
 # The image: Debian 13 with nftables and network tools. 'docker build'
 # can't reach the network on some hosts, so it is made with run + commit.
 if ! docker image inspect "$IMAGE" >/dev/null 2>&1; then
@@ -104,6 +105,7 @@ ruleset: /w/data/ruleset.nft
 backup: {dir: /w/backups}
 log: {level: debug}
 stats: {database: /w/data/stats.db}
+jarl: {server: "http://127.0.0.1:8053", token: e2e-jarl-token, refresh: 10s}
 EOF
 { cat "$WORK/housecarl.yaml"; echo "shadow: {enabled: true}"; } > "$WORK/housecarl-shadow.yaml"
 CONF=housecarl.yaml
@@ -322,7 +324,7 @@ send 2000000 >/dev/null 2>&1
 run "used up: the device is cut off" 1 send 1000
 run "the usage" 0 H quotas
 contains "e2e quota.*1.0 MB each.*by hand"
-contains "$CLIENT4 (e2e-client)  *1\.[0-9] MB"
+contains "$CLIENT4 (e2e-client)  *1\.[0-9] MB (1[0-9][0-9]%)"
 stop; start
 run "after a restart, still used up" 1 send 1000
 run "the usage after a restart" 0 H quotas
@@ -342,6 +344,15 @@ run "the device is back" 0 send 1000
 run "the reset is audited" 0 H audit --action quota.
 contains "quota.reset"
 contains "quota.give"
+# Counted in total now: what the device used carries over; per
+# destination can't take it, and says so.
+run "within the quota" 0 send 300000
+run "to one total" 0 H rule update "$QR" --quota 1mbytes,over
+not_contains "quota_restarts"
+run "the total carried over" 0 H quotas
+contains "e2e quota)  *[0-9.]* KB ([0-9]*%)"
+run "per destination starts again" 0 H rule update "$QR" --quota 1mbytes,over,per-destination
+contains "quota_restarts"
 run "the quota rule goes" 0 H rule delete -y "$QR"
 
 # ---- the zone matrix, of the imported ruleset
@@ -471,6 +482,96 @@ run "the VLAN rule goes" 0 H rule delete -y "$VR"
 run "the VLAN zone goes" 0 H zone delete -y iot
 R ip link del enp2s0.30
 
+# ---- ban lists: bans kept from the firewall, a host, or everything
+
+# DNS is open to the internet on the router (tcp/53): a listener answers.
+docker exec -d ${P}-router sh -c 'while [ ! -f /tmp/nodns ]; do echo dns | nc -N -l 0.0.0.0 53; done'
+sleep 1
+run "the router's tcp/53 from the internet" 0 connect net $WAN4 53
+contains "^dns$"
+run "a ban list for the firewall" 0 H banlist add router --scope firewall
+# The lab's internet host shares the router's WAN /64: ban IPv6 addresses
+# alone (a /64 would hold the router's own, and is refused).
+run "a ban list for jellyfin" 0 H banlist add jf --scope hosts --host $JF4 --host $JF6 --group-v6 128
+run "a ban list for everything" 0 H banlist add edge --scope everything --max-time 1h
+run "the lists" 0 H banlist list
+contains "jf  *hosts  *10.88.10.57, 2001:db8:7f3d:10::57  *0"
+# The firewall's own DNS, for the internet host.
+run "ban from the firewall's tcp/53" 0 H ban router $NET4 --tcp dns --reason "e2e"
+contains "banned $NET4, tcp/53, in router"
+run "the router's DNS is cut for it" 1 connect net $WAN4 53
+run "the port forward isn't (scope firewall)" 0 connect net $WAN4 8096
+contains "^jellyfin$"
+run "the ban in the ruleset" 0 R nft list ruleset
+contains "ip saddr . meta l4proto . th dport @ban_[0-9]*_v4_svc counter packets [1-9]"
+run "lift it" 0 H unban router $NET4
+contains "1 bans lifted"
+run "DNS again" 0 connect net $WAN4 53
+contains "^dns$"
+# fail2ban on jellyfin, with Housecarl's action and a token for its list.
+run "a user for jellyfin's fail2ban" 0 H user add f2b-jf --no-password --grant bans:write:jf
+R sh -c "/w/hc token create jf --user f2b-jf > /w/f2b.token 2>/dev/null"
+run "its token" 0 test -s "$WORK/f2b.token"
+# f2b ACTION ip=… port=…: the action's command from contrib/, with the
+# jail's values, as fail2ban runs it (on jellyfin).
+f2b() {
+	local conf="$ROOT/contrib/fail2ban/action.d/housecarl.conf" a=$1; shift
+	local cmd curl
+	cmd=$(awk -v a="$a" '$0 ~ "^"a" *=" {sub(/^[^=]*= */,""); print; on=1; next} on && /^[ \t]/ {sub(/^[ \t]+/,""); print; next} {on=0}' "$conf" | tr '\n' ' ')
+	curl=$(sed -n 's/^_curl *= *//p' "$conf")
+	cmd=${cmd//<_curl>/$curl}
+	local kv
+	for kv in "$@" "list=jf" "url=http://$LAN4:8070" "tokenfile=/w/f2b.token" "curlopts=" "protocol=tcp" "bantime=600" "name=jellyfin"; do
+		cmd=${cmd//<${kv%%=*}>/${kv#*=}}
+	done
+	docker exec ${P}-jf sh -c "$cmd"
+}
+run "fail2ban bans the internet host's https" 0 f2b actionban ip=$NET4 port=https
+run "the port forward to jellyfin is cut for it" 1 connect net $WAN4 8096
+run "the router's DNS isn't (scope hosts)" 0 connect net $WAN4 53
+run "fail2ban bans its IPv6 address" 0 f2b actionban ip=$NET6 port=https
+run "IPv6 to jellyfin's 443 is cut" 1 connect net $JF6 443
+run "the bans" 0 H bans jf
+contains "$NET4  *tcp/443 .*f2b-jf  *fail2ban/jellyfin"
+contains "$NET6  *tcp/443"
+run "never the inside" 22 f2b actionban ip=$CLIENT4 port=https
+run "refused, audited" 0 H audit --action ban.add
+contains "failure.*inside"
+run "fail2ban unbans" 0 f2b actionunban ip=$NET4
+run "the port forward works again" 0 connect net $WAN4 8096
+contains "^jellyfin$"
+run "unbanning what Housecarl already let go is no error" 0 f2b actionunban ip=$NET4
+run "and the IPv6 ban" 0 f2b actionunban ip=$NET6
+run "jellyfin by IPv6 again" 0 connect net $JF6 443
+contains "jellyfin6"
+run "the token can't ban elsewhere" 22 f2b actionban ip=$NET4 port=https list=router
+# Everything, cutting a connection that is open, and kept over a restart.
+R touch /tmp/nodns
+connect net $WAN4 53 >/dev/null 2>&1
+docker exec -d ${P}-router sh -c 'nc -l 0.0.0.0 53 > /w/held.out'
+sleep 1
+docker exec -d ${P}-net sh -c "sleep 30 | nc $WAN4 53"
+sleep 1
+run "an open connection from the internet host" 0 H connections --search "$NET4 :53"
+contains "$NET4:[0-9]*  *$WAN4:53"
+run "ban it from everything" 0 H ban edge $NET4 --time 1d
+contains "banned $NET4, every port, in edge (ends in 1h)"
+contains "[1-9][0-9]* connections closed"
+run "its connection is gone" 0 H connections --search "$NET4 :53"
+not_contains ":53"
+run "nothing gets through for it" 1 connect net $WAN4 8096
+stop
+run "restart housecarld" 0 start
+run "the ban is back after the restart" 0 R nft list ruleset
+contains "$NET4 timeout [0-9hms]* expires"
+run "still nothing for it" 1 connect net $WAN4 8096
+run "lift it" 0 H unban edge $NET4
+run "the ban is out of the ruleset" 0 R nft list ruleset
+not_contains "$NET4 timeout"
+run "the port forward again" 0 connect net $WAN4 8096
+contains "^jellyfin$"
+run "the lists go" 0 sh -c "docker exec ${P}-router /w/hc banlist delete -y router && docker exec ${P}-router /w/hc banlist delete -y jf && docker exec ${P}-router /w/hc banlist delete -y edge"
+
 # ---- renaming a zone others refer to
 
 run "rename the imported dhcp zone" 0 H zone update dhcp --name lan
@@ -480,6 +581,77 @@ not_contains "dhcp "
 run "the ruleset is unchanged by it" 0 R nft list chain inet housecarl input
 contains 'iifname "enp2s0" udp dport 67'
 
+# ---- a set from Jarl: names' addresses, kept up to date
+
+# A fake Jarl on the router: example.com in views internal and external.
+# jf's AAAA is jellyfin's; ssh.example.com is a CNAME for it; the internet
+# host's address is outside the LAN.
+jarl_data() { # JF_AAAA
+	cat > "$WORK/jarl.json" <<EOJ
+{"zones": [{"id": 1, "name": "example.com.", "view": "internal", "type": "primary"},
+           {"id": 2, "name": "example.com.", "view": "external", "type": "primary"}],
+ "records": {"1": [{"name": "jf.example.com.", "type": "A", "data": "$JF4"},
+                   {"name": "jf.example.com.", "type": "AAAA", "data": "$1"},
+                   {"name": "ssh.example.com.", "type": "CNAME", "data": "jf.example.com."},
+                   {"name": "net.example.com.", "type": "AAAA", "data": "$NET6"}],
+             "2": [{"name": "ssh.example.com.", "type": "AAAA", "data": "$NET6"}]}}
+EOJ
+}
+jarl_data $JF6
+docker exec -d ${P}-router sh -c '/w/fakejarl -listen 127.0.0.1:8053 -data /w/jarl.json -token e2e-jarl-token >> /w/fakejarl.log 2>&1'
+sleep 1
+run "IPv6 ssh to jellyfin is dropped" 1 connect net $JF6 22
+run "a set from Jarl" 0 H set add jfssh --jarl ssh.example.com --within lan
+run "a name in two views needs its view" 0 H set jarl jfssh --refresh
+contains "in Jarl's views external, internal: name the view"
+run "name the views" 0 H set update jfssh --jarl ssh.example.com@internal --jarl net.example.com@internal
+JR=$(H -o id rule add forward --in wan --to jfssh --service ssh --first --comment "e2e jarl")
+run "the set's addresses, CNAME followed" 0 H set jarl jfssh --refresh
+contains "ssh.example.com → jf.example.com  *internal  *$JF4  *yes"
+contains "ssh.example.com → jf.example.com  *internal  *$JF6  *yes"
+contains "net.example.com  *internal  *$NET6  *no: not within lan"
+run "in the ruleset" 0 R nft list set inet housecarl jfssh_v6
+contains "$JF6"
+not_contains "$NET6"
+run "the address outside is warned of" 0 H status
+contains "jarl_outside"
+run "IPv6 ssh to jellyfin through the Jarl set" 0 connect net $JF6 22
+contains "^ssh$"
+# The record changes in Jarl: within the refresh, the set follows.
+jarl_data 2001:db8:7f3d:10::99
+sleep 12
+run "the new address, without a change in Housecarl" 0 R nft list set inet housecarl jfssh_v6
+contains "2001:db8:7f3d:10::99"
+not_contains "$JF6"
+run "ssh to the old address is dropped again" 1 connect net $JF6 22
+run "no history entry for it" 0 H history list
+contains "update set jfssh"
+not_contains "10::99"
+run "an audit record" 0 H audit --action set.jarl
+contains "added 2001:db8:7f3d:10::99"
+# Jarl goes away: the set keeps what it had, over a restart too.
+jarl_data $JF6
+H set jarl jfssh --refresh >/dev/null
+R sh -c 'kill $(pidof fakejarl)'
+run "Jarl down: the set keeps its addresses" 0 H set jarl jfssh --refresh
+contains "Reading Jarl failed"
+contains "$JF6  *yes"
+run "still through" 0 connect net $JF6 22
+contains "^ssh$"
+run "warned" 0 H status
+contains "jarl_unreachable"
+stop
+run "restart housecarld, Jarl still down" 0 start
+run "the set is back from the database" 0 R nft list set inet housecarl jfssh_v6
+contains "$JF6"
+run "the boot ruleset has its addresses" 0 R grep -q "$JF6" /w/data/ruleset.nft
+run "still through after the restart" 0 connect net $JF6 22
+contains "^ssh$"
+run "the Jarl rule goes" 0 H rule delete -y "$JR"
+run "the Jarl set goes" 0 H set delete -y jfssh
+run "no Jarl warning left" 0 H status
+not_contains "jarl_"
+
 # ---- restart and boot
 
 stop

scripts/fakejarl/main.go

@@ -0,0 +1,63 @@
+// Command fakejarl answers the part of Jarl's API that Housecarl's Jarl
+// sets read (GET /zones, GET /zones/{id}/records), from a JSON file read
+// again on each request, so the e2e test can change records:
+//
+//	{"zones": [{"id": 1, "name": "example.com.", "view": "internal", "type": "primary"}],
+//	 "records": {"1": [{"name": "nas.example.com.", "type": "A", "data": "10.0.0.5"}]}}
+//
+// Usage: fakejarl -listen 127.0.0.1:8053 -data jarl.json -token SECRET
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"log"
+	"net/http"
+	"os"
+	"strings"
+)
+
+type data struct {
+	Zones   []map[string]any            `json:"zones"`
+	Records map[string][]map[string]any `json:"records"`
+}
+
+func main() {
+	listen := flag.String("listen", "127.0.0.1:8053", "address to listen on")
+	file := flag.String("data", "jarl.json", "the zones and records")
+	token := flag.String("token", "", "the API token Housecarl must send")
+	flag.Parse()
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("Authorization") != "Bearer "+*token {
+			w.WriteHeader(http.StatusUnauthorized)
+			w.Write([]byte(`{"error": {"code": "unauthorized", "message": "bad token"}}`))
+			return
+		}
+		b, err := os.ReadFile(*file)
+		var d data
+		if err == nil {
+			err = json.Unmarshal(b, &d)
+		}
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		p := strings.TrimPrefix(r.URL.Path, "/api/v1")
+		switch {
+		case p == "/zones":
+			json.NewEncoder(w).Encode(d.Zones)
+		case strings.HasPrefix(p, "/zones/") && strings.HasSuffix(p, "/records"):
+			id := strings.TrimSuffix(strings.TrimPrefix(p, "/zones/"), "/records")
+			recs := d.Records[id]
+			if recs == nil {
+				recs = []map[string]any{}
+			}
+			json.NewEncoder(w).Encode(recs)
+		default:
+			w.WriteHeader(http.StatusNotFound)
+			w.Write([]byte(`{"error": {"code": "not_found", "message": "not found"}}`))
+		}
+	})
+	log.Fatal(http.ListenAndServe(*listen, nil))
+}

scripts/gitea-release.sh

@@ -114,7 +114,7 @@ done
 files="$files dist/SHA256SUMS"
 
 # The release (created, or found when publishing again).
-release=$(call 404 "$api/releases/tags/$tag")
+release=$(call 404 "$api/releases/tags/$(printf '%s' "$tag" | sed 's/+/%2B/g')")
 id=$(printf '%s\n' "$release" | jq -r '.id // empty')
 if [ -z "$id" ]; then
 	body=$(jq -n --arg tag "$tag" --arg notes "$notes" --argjson pre "$prerelease" \
@@ -127,7 +127,8 @@ for f in $files; do
 	name=${f#dist/}
 	old=$(printf '%s\n' "$release" | jq -r --arg n "$name" '.assets[]? | select(.name == $n) | .id')
 	[ -z "$old" ] || call "" -X DELETE "$api/releases/$id/assets/$old" >/dev/null
-	call "" -X POST -F "attachment=@$f" "$api/releases/$id/assets?name=$name" >/dev/null
+	# A + (build metadata, 0.2.0-rc.3+1a2b3c4) would be a space in a query.
+	call "" -X POST -F "attachment=@$f" "$api/releases/$id/assets?name=$(printf '%s' "$name" | sed 's/+/%2B/g')" >/dev/null
 	echo "gitea-release: attached $name"
 done