Release 0.4.0-rc.1

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

CHANGELOG.md

@@ -8,6 +8,66 @@ All notable changes to Jarl are documented here. The format follows
 
 ### Added
 
+- Blocking (docs/blocking.md): named answers "doesn't exist" for ads,
+  trackers and malware, using BIND's response policy zones.
+  - Blocklists in Adblock, hosts or plain-domain format, downloaded by jarld
+    and checked daily (`blocking.refresh`). A list is downloaded only when
+    the server says it changed, checked with named-checkzone, and reloaded
+    only when its content differs; a failed update keeps the previous
+    version and shows on the dashboard.
+  - Your own block and allow rules, for a domain and the names below it or
+    the exact name. Rules take precedence over every list, and the most
+    specific rule wins.
+  - Lists and rules apply to chosen views, or to every view that offers
+    recursion. They are configuration: staged, reviewed and reverted like
+    any change.
+  - Checking a name says whether it is blocked and by which rule or list
+    entry, with an Allow button in the web UI.
+  - Web UI: a Blocking page, with well-known lists to pick and named's
+    memory per list. CLI: `jarl blocklist` and `jarl block`. API:
+    `/blocking/lists`, `/blocking/rules`, `/blocking/check`.
+  - Pausing: `jarl block pause [DURATION]` or the Blocking page lets every
+    name through for a while (at most a day); blocking resumes by itself.
+    The lists stay loaded, so it takes effect at once.
+  - Statistics: blocked queries over time (a line on the queries chart)
+    and their share, blocked per list, the most blocked names and the
+    clients with the most blocked queries (`jarl stats top blocked`,
+    `top blocked-clients`). Blocked answers no longer count as names that
+    don't exist.
+  - The view choice in the web UI's forms is a compact dropdown, however
+    many views there are.
+  - A `blocking` permission; database schema 6.
+
+### Changed
+
+- Web UI options (server, top-level, view and zone): values with blocks,
+  such as logging, are shown and edited laid out as in named.conf, over
+  several lines with indentation. The editor grows with its content, Tab
+  indents and Enter keeps the indentation (Esc, then Tab, moves on). With
+  a draft open, the tables show the draft's values, so a staged edit stays
+  visible after Save.
+- The pending-changes banner has an Apply now button: it applies your
+  draft without going to the Changes page, and stays on the page you're
+  on. If the changes are refused, a dialog says why and links to Changes.
+- Blocking page: blocklists and rules have an Edit button (name, URL,
+  views, comment; a rule's action and scope). The list button that
+  downloads now is called Refresh, like `jarl blocklist refresh`.
+- Records table: disabled records are hatched and have a "disabled" badge
+  next to their name, instead of only a muted colour and a badge in the
+  comment column.
+
+### Fixed
+
+- Blocking page, checking a name: when your own block rule is for that very
+  name, it offers to remove the rule instead of an allow rule, which was
+  refused as a second rule for the same name. It also names the rule that
+  matched rather than the policy zone entry.
+- docs/validation.md lacked the `disabled_conflict` warning added in 0.3.0.
+
+## [0.3.0] - 2026-10-09
+
+### Added
+
 - Disabled records: a record can be disabled instead of deleted. It stays
   in Jarl with its ID, TTL and comment but is left out of the zone (the
   zone file lists it as a comment), and enabling it puts it back exactly
@@ -35,6 +95,14 @@ All notable changes to Jarl are documented here. The format follows
   and `list` prints the IDs too. With a change (`jarl record add ... -o
   id`) they apply to the changed object.
 
+- Statistics: client lists (busiest and refused clients, in the web UI,
+  `jarl stats top clients|refused` and `jarl stats summary`) show the host
+  name Jarl's records have for each address: the PTR record's target, or
+  else the name of an A/AAAA record. Looked up in Jarl's own data, so no
+  DNS queries; an address without a record shows as before.
+- Zones list: a padlock after each signed zone's name, linking to its
+  DNSSEC tab (open and amber while signing is being turned off).
+
 ### Changed
 
 - The web UI and API can listen on ports below 1024, such as 443:

README.md

@@ -71,6 +71,10 @@ error: www.adbraun.lol has a CNAME, so it can't have any other records (found A)
   queries, record types, cache hit rate. Shown in the web UI and the CLI,
   and exportable as JSON. Stored as aggregates in a separate database with
   retention you set.
+* **Blocking** like Pi-hole, done by named itself: blocklists (Adblock,
+  hosts or plain domains) downloaded and kept up to date, your own block
+  and allow rules that beat every list, per view, with "why is this
+  blocked?" checks and blocked counts in the statistics.
 * **Let's Encrypt DNS-01** built in: `jarl acme` plus certbot, acme.sh and lego
   hooks, an HTTPS-only endpoint for lego's and Traefik's `httpreq` provider,
   and CNAME delegation to a dedicated ACME zone.
@@ -116,6 +120,7 @@ in `/etc/jarl/jarl.yaml` to reach it from your management network.
 | [docs/dnssec.md](docs/dnssec.md) | DNSSEC signing, going public with your own name servers, Porkbun |
 | [docs/acme.md](docs/acme.md) | Let's Encrypt DNS-01 with certbot, acme.sh, lego and Traefik |
 | [docs/stats.md](docs/stats.md) | Query statistics: enabling, what is collected, retention |
+| [docs/blocking.md](docs/blocking.md) | Blocking ads, trackers and malware: blocklists, your own rules, views, memory |
 | [docs/validation.md](docs/validation.md) | Every check Jarl makes |
 | [docs/operations.md](docs/operations.md) | Backups, drift, failures, recovery, monitoring |
 | [docs/development.md](docs/development.md) | Code layout, tests against real BIND, conventions |
@@ -166,10 +171,11 @@ review step.
 
 ## Status
 
-Version 0.2.0 is the current release, and 0.3.0 is in testing
-(0.3.0-rc.1). 0.2.0 added DNSSEC signing, Porkbun support, two-factor
-login and view colours; 0.3.0 adds disabled records and scripting output
-for the CLI. Jarl is feature-complete for one server's configuration.
+Version 0.3.0 is the current release, and 0.4.0 is in testing
+(0.4.0-rc.1): it adds blocking (blocklists and your own rules, like
+Pi-hole, done by named). 0.3.0 added disabled records, script-friendly
+CLI output and client names in the statistics, on top of 0.2.0's DNSSEC
+signing, Porkbun support, two-factor login and view colours. Jarl is feature-complete for one server's configuration.
 Managing several servers from one jarld and dynamic updates are not
 handled yet ([concepts.md](docs/concepts.md#what-jarl-deliberately-doesnt-do-yet)).
 

VERSION

@@ -1 +1 @@
-0.3.0-rc.1
+0.4.0-rc.1

cmd/jarl/blocking.go

@@ -0,0 +1,474 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"jarl/internal/api"
+	"jarl/internal/blocking"
+)
+
+// ---- blocking (docs/blocking.md)
+
+// viewsBody adds the --view flags to a request body: names, or "auto" for
+// every view that offers recursion.
+func viewsBody(body map[string]any, views []string) {
+	if len(views) == 1 && strings.EqualFold(views[0], "auto") {
+		body["views"] = []string{}
+	} else if len(views) > 0 {
+		body["views"] = views
+	}
+}
+
+func viewsText(views []string, auto bool) string {
+	switch {
+	case auto:
+		return "auto (" + strings.Join(views, ", ") + ")"
+	case len(views) == 0:
+		return "-"
+	}
+	return strings.Join(views, ", ")
+}
+
+func blocklistCmd() *cobra.Command {
+	cmd := &cobra.Command{Use: "blocklist", Aliases: []string{"blocklists"}, Short: "Blocklists: domains to block, downloaded and kept up to date",
+		Long: `Blocklists are downloaded by jarld and turned into response policy zones, so
+named answers "doesn't exist" for the domains on them (docs/blocking.md).
+Hosts, plain domain and Adblock (||domain^) lists work. Your own block and
+allow rules ('jarl block') take precedence over every list.`}
+	var views []string
+	var comment string
+
+	list := &cobra.Command{
+		Use:   "list",
+		Short: "List blocklists and their state",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var lists []api.Blocklist
+			if err := c.Get(ctx(), "/blocking/lists", nil, &lists); err != nil {
+				return err
+			}
+			return output(lists, func(w io.Writer) {
+				fmt.Fprintln(w, "NAME\tSTATE\tDOMAINS\tVIEWS\tUPDATED\tMEMORY\tURL")
+				for _, b := range lists {
+					domains, updated, mem := "-", "-", "-"
+					if s := b.Status; s != nil && s.UpdatedAt != nil {
+						domains, updated = fmt.Sprint(s.Entries), s.UpdatedAt.Local().Format("2006-01-02 15:04")
+					}
+					if b.MemoryMB > 0 {
+						mem = fmt.Sprintf("~%d MB", b.MemoryMB)
+					}
+					fmt.Fprintf(w, "%s\t%s\t%s\t%s\t%s\t%s\t%s\n", b.Name, b.State, domains, viewsText(b.Views, b.AutoViews), updated, mem, b.URL)
+				}
+				for _, b := range lists {
+					if b.Status != nil && b.Status.Error != "" {
+						fmt.Fprintf(w, "\n%s: %s\n", b.Name, b.Status.Error)
+					}
+				}
+			})
+		},
+	}
+
+	add := &cobra.Command{
+		Use:   "add NAME URL",
+		Short: "Add a blocklist (jarld downloads it right away)",
+		Long: `Add a blocklist. NAME is a short label (letters, digits, hyphens). Without
+--view the list applies to every view that offers recursion.
+
+  jarl blocklist add hagezi-pro https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/pro.txt
+  jarl blocklist add stevenblack https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts --view internal`,
+		Args: cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			body := map[string]any{"name": args[0], "url": args[1]}
+			viewsBody(body, views)
+			if comment != "" {
+				body["comment"] = comment
+			}
+			resp, err := c.Mutate(ctx(), "POST", "/blocking/lists", nil, body)
+			if err != nil {
+				return err
+			}
+			if err := report(resp); err != nil || flagQuiet || !resp.Applied {
+				return err
+			}
+			fmt.Println("jarld downloads the list in the background; 'jarl blocklist list' shows when it's in use.")
+			return nil
+		},
+	}
+	add.Flags().StringArrayVar(&views, "view", nil, "a view it applies to (repeat for several; default: every view that offers recursion)")
+	add.Flags().StringVar(&comment, "comment", "", "comment")
+
+	var rename, newURL string
+	update := &cobra.Command{
+		Use:   "update LIST",
+		Short: "Change a blocklist's name, URL, views or comment",
+		Example: `  jarl blocklist update hagezi --url https://example.org/new-list.txt
+  jarl blocklist update hagezi --view internal --view guest
+  jarl blocklist update hagezi --view auto     # every view that offers recursion`,
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			body := map[string]any{}
+			f := cmd.Flags()
+			if f.Changed("name") {
+				body["name"] = rename
+			}
+			if f.Changed("url") {
+				body["url"] = newURL
+			}
+			if f.Changed("comment") {
+				body["comment"] = comment
+			}
+			viewsBody(body, views)
+			if len(body) == 0 {
+				return fmt.Errorf("nothing to change (see --help)")
+			}
+			resp, err := c.Mutate(ctx(), "PATCH", "/blocking/lists/"+url.PathEscape(args[0]), nil, body)
+			if err != nil {
+				return err
+			}
+			return report(resp)
+		},
+	}
+	update.Flags().StringVar(&rename, "name", "", "new name")
+	update.Flags().StringVar(&newURL, "url", "", "new URL")
+	update.Flags().StringArrayVar(&views, "view", nil, `a view it applies to (repeat for several; "auto": every view that offers recursion)`)
+	update.Flags().StringVar(&comment, "comment", "", "new comment")
+
+	toggle := func(disable bool) *cobra.Command {
+		verb := map[bool]string{true: "disable", false: "enable"}[disable]
+		return &cobra.Command{
+			Use:   verb + " LIST",
+			Short: map[bool]string{true: "Stop using a blocklist (it is kept, and re-enabled without downloading)", false: "Use a disabled blocklist again"}[disable],
+			Args:  cobra.ExactArgs(1),
+			RunE: func(cmd *cobra.Command, args []string) error {
+				c, err := newClient()
+				if err != nil {
+					return err
+				}
+				resp, err := c.Mutate(ctx(), "PATCH", "/blocking/lists/"+url.PathEscape(args[0]), nil, map[string]any{"disabled": disable})
+				if err != nil {
+					return err
+				}
+				return report(resp)
+			},
+		}
+	}
+
+	var yes bool
+	del := &cobra.Command{
+		Use:   "delete LIST",
+		Short: "Delete a blocklist",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			if !confirm("Delete blocklist "+args[0]+"?", yes) {
+				return fmt.Errorf("canceled")
+			}
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			resp, err := c.Mutate(ctx(), "DELETE", "/blocking/lists/"+url.PathEscape(args[0]), nil, nil)
+			if err != nil {
+				return err
+			}
+			return report(resp)
+		},
+	}
+	del.Flags().BoolVarP(&yes, "yes", "y", false, "don't ask")
+
+	var force bool
+	refresh := &cobra.Command{
+		Use:   "refresh [LIST...]",
+		Short: "Download blocklists now (all enabled ones without LIST)",
+		Long: `Download blocklists now instead of waiting for their next check
+(blocking.refresh in jarl.yaml, daily by default). A list is only replaced
+when its content changed; --force downloads it even when the server says
+it hasn't.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			names := args
+			if len(names) == 0 {
+				var lists []api.Blocklist
+				if err := c.Get(ctx(), "/blocking/lists", nil, &lists); err != nil {
+					return err
+				}
+				for _, b := range lists {
+					if b.State != "disabled" && b.State != "idle" {
+						names = append(names, b.Name)
+					}
+				}
+			}
+			if flagDryRun {
+				fmt.Printf("would download: %s\n", strings.Join(names, ", "))
+				return nil
+			}
+			failed := 0
+			for _, n := range names {
+				var b api.Blocklist
+				start := time.Now()
+				err := c.Do(ctx(), "POST", "/blocking/lists/"+url.PathEscape(n)+"/refresh", q("force", map[bool]string{true: "1"}[force]), nil, &b)
+				switch {
+				case err != nil:
+					failed++
+					fmt.Printf("%s: %v\n", n, err)
+				case b.Status != nil && b.Status.Error != "":
+					failed++
+					fmt.Printf("%s: %s (the previous version stays in use)\n", n, b.Status.Error)
+				case b.Status != nil:
+					fmt.Printf("%s: %d domains (%d lines skipped), checked in %s\n", n, b.Status.Entries, b.Status.Skipped, time.Since(start).Round(100*time.Millisecond))
+				}
+			}
+			if failed > 0 {
+				return &checkFailed{fmt.Sprintf("%d of %d lists could not be updated", failed, len(names))}
+			}
+			return nil
+		},
+	}
+	refresh.Flags().BoolVar(&force, "force", false, "download even when the server says the list hasn't changed")
+
+	cmd.AddCommand(list, add, update, toggle(true), toggle(false), del, refresh)
+	return cmd
+}
+
+func blockCmd() *cobra.Command {
+	cmd := &cobra.Command{Use: "block", Short: "Your own block and allow rules, and checking what is blocked",
+		Long: `Rules block a domain, or allow it despite the blocklists ('jarl blocklist').
+A rule covers the domain and every name below it, unless --exact. Rules
+take precedence over every list, and the most specific rule wins: allow
+cdn.example.com overrides block example.com for cdn.example.com and the
+names below it (docs/blocking.md).`}
+	var views []string
+	var comment, view string
+	var exact bool
+
+	addRule := func(action string) *cobra.Command {
+		c := &cobra.Command{
+			Use:   map[string]string{"block": "add DOMAIN", "allow": "allow DOMAIN"}[action],
+			Short: map[string]string{"block": "Block a domain (and the names below it)", "allow": "Allow a domain (and the names below it) that a blocklist blocks"}[action],
+			Example: map[string]string{
+				"block": "  jarl block add doubleclick.net\n  jarl block add telemetry.example.com --exact --view internal",
+				"allow": "  jarl block allow cdn.example.com\n  jarl block allow login.example.com --exact",
+			}[action],
+			Args: cobra.ExactArgs(1),
+			RunE: func(cmd *cobra.Command, args []string) error {
+				c, err := newClient()
+				if err != nil {
+					return err
+				}
+				body := map[string]any{"name": args[0], "action": action}
+				if exact {
+					body["exact"] = true
+				}
+				viewsBody(body, views)
+				if comment != "" {
+					body["comment"] = comment
+				}
+				resp, err := c.Mutate(ctx(), "POST", "/blocking/rules", nil, body)
+				if err != nil {
+					return err
+				}
+				return report(resp)
+			},
+		}
+		c.Flags().BoolVar(&exact, "exact", false, "only this name, not the names below it")
+		c.Flags().StringArrayVar(&views, "view", nil, "a view it applies to (repeat for several; default: every view that offers recursion)")
+		c.Flags().StringVar(&comment, "comment", "", "comment")
+		return c
+	}
+
+	list := &cobra.Command{
+		Use:   "list",
+		Short: "List your block and allow rules",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var rules []api.BlockRule
+			if err := c.Get(ctx(), "/blocking/rules", nil, &rules); err != nil {
+				return err
+			}
+			note := pausedNote(c)
+			return output(rules, func(w io.Writer) {
+				if note != "" {
+					fmt.Fprintln(w, note)
+				}
+				fmt.Fprintln(w, "ID\tACTION\tDOMAIN\tCOVERS\tVIEWS\tCOMMENT")
+				for _, r := range rules {
+					covers := "and below"
+					if r.Exact {
+						covers = "exact"
+					}
+					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\t%s\n", r.ID, r.Action, r.Name, covers, viewsText(r.Views, r.AutoViews), r.Comment)
+				}
+			})
+		},
+	}
+
+	var id int64
+	var missingOK bool
+	del := &cobra.Command{
+		Use:   "delete DOMAIN  |  delete --id ID",
+		Short: "Delete the rules for a domain (or one rule by ID)",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var resp *api.MutationResponse
+			switch {
+			case id > 0:
+				resp, err = c.Mutate(ctx(), "DELETE", fmt.Sprintf("/blocking/rules/%d", id), nil, nil)
+			case len(args) == 1:
+				qv := q("name", args[0], "view", view)
+				if missingOK {
+					qv.Set("missing_ok", "1")
+				}
+				resp, err = c.Mutate(ctx(), "DELETE", "/blocking/rules", qv, nil)
+			default:
+				return fmt.Errorf("give DOMAIN, or --id")
+			}
+			if err != nil {
+				return err
+			}
+			if !resp.Applied && !resp.Staged && !resp.DryRun {
+				fmt.Println("nothing to do")
+				return nil
+			}
+			return report(resp)
+		},
+	}
+	del.Flags().Int64Var(&id, "id", 0, "delete the rule with this ID")
+	del.Flags().StringVar(&view, "view", "", "only the rules that apply in this view")
+	del.Flags().BoolVar(&missingOK, "missing-ok", false, "succeed when there is no such rule")
+
+	check := &cobra.Command{
+		Use:   "check DOMAIN",
+		Short: "Show whether a name is blocked, and by which rule or list",
+		Args:  cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			var matches []blocking.Match
+			if err := c.Get(ctx(), "/blocking/check", q("name", args[0]), &matches); err != nil {
+				return err
+			}
+			note := pausedNote(c)
+			return output(matches, func(w io.Writer) {
+				if note != "" {
+					fmt.Fprint(w, note+"While it is, every name is answered. Otherwise:\n")
+				}
+				if len(matches) == 0 {
+					fmt.Fprintln(w, "Blocking isn't set up in any view.")
+					return
+				}
+				for _, m := range matches {
+					where := ""
+					if m.View != "" {
+						where = "view " + m.View + ":\t"
+					}
+					switch {
+					case m.Result == "none":
+						fmt.Fprintf(w, "%snot blocked\n", where)
+					case m.List != "":
+						fmt.Fprintf(w, "%sblocked by blocklist %s (entry %s)\n", where, m.List, m.Entry)
+					default:
+						fmt.Fprintf(w, "%s%s by your rule %d (entry %s)\n", where, m.Result, m.RuleID, m.Entry)
+					}
+				}
+			})
+		},
+	}
+
+	pause := &cobra.Command{
+		Use:   "pause [DURATION]",
+		Short: "Let every name through for a while (default 10m, at most 24h)",
+		Long: `Pause blocking: every name is answered normally until the time is up,
+then blocking resumes by itself. Useful to see whether blocking is what
+breaks a site. The lists stay loaded, so pausing and resuming take effect
+at once.
+
+  jarl block pause          # 10 minutes
+  jarl block pause 1h
+  jarl block resume`,
+		Args: cobra.MaximumNArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			d := 10 * time.Minute
+			if len(args) == 1 {
+				var err error
+				if d, err = time.ParseDuration(args[0]); err != nil || d < time.Minute {
+					return fmt.Errorf("invalid duration %q (like 10m or 2h)", args[0])
+				}
+			}
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			resp, err := c.Mutate(ctx(), "POST", "/blocking/pause", nil, map[string]any{"minutes": int(d.Round(time.Minute) / time.Minute)})
+			if err != nil {
+				return err
+			}
+			if err := report(resp); err != nil || flagQuiet || !resp.Applied {
+				return err
+			}
+			fmt.Printf("Blocking is paused until %s.\n", time.Now().Add(d.Round(time.Minute)).Format("15:04"))
+			return nil
+		},
+	}
+	resume := &cobra.Command{
+		Use:   "resume",
+		Short: "End a pause: block again now",
+		Args:  cobra.NoArgs,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			resp, err := c.Mutate(ctx(), "POST", "/blocking/resume", nil, nil)
+			if err != nil {
+				return err
+			}
+			return report(resp)
+		},
+	}
+
+	cmd.AddCommand(addRule("block"), addRule("allow"), list, del, check, pause, resume)
+	return cmd
+}
+
+// pausedNote returns a line about a pause of blocking, or "".
+func pausedNote(c interface {
+	Get(context.Context, string, url.Values, any) error
+}) string {
+	var st struct {
+		PausedUntil *time.Time `json:"paused_until"`
+	}
+	if c.Get(ctx(), "/blocking/status", nil, &st) != nil || st.PausedUntil == nil {
+		return ""
+	}
+	return "Blocking is paused until " + st.PausedUntil.Local().Format("2006-01-02 15:04") + " ('jarl block resume' ends it).\n"
+}

cmd/jarl/complete.go

@@ -76,6 +76,8 @@ func argCompletion(c *cobra.Command) cobra.CompletionFunc {
 			return append([]string{"default"}, model.ViewColors...), cobra.ShellCompDirectiveNoFileComp
 		case p == "ACL":
 			return lookup(cmd, "acl")
+		case p == "LIST":
+			return lookup(cmd, "blocklist")
 		case p == "USER":
 			return lookup(cmd, "user")
 		case p == "KEY" && parent == "tsig":
@@ -199,6 +201,14 @@ func lookup(cmd *cobra.Command, kind string) ([]cobra.Completion, cobra.ShellCom
 		for _, v := range views {
 			addName(v.Name, v.Comment)
 		}
+	case "blocklist":
+		var lists []api.Blocklist
+		if c.Get(ctx(), "/blocking/lists", nil, &lists) != nil {
+			return nil, none
+		}
+		for _, b := range lists {
+			addName(b.Name, b.URL)
+		}
 	case "acl":
 		var acls []api.ACL
 		if c.Get(ctx(), "/acls", nil, &acls) != nil {

cmd/jarl/main.go

@@ -250,7 +250,7 @@ Exit codes: 0 ok, 1 error, 3 not authenticated or not allowed, 4 not found,
 			root.AddCommand(c)
 		}
 	}
-	add("dns", zoneCmd(), recordCmd(), viewCmd(), aclCmd(), tsigCmd(), optionCmd(), settingsCmd(), acmeCmd(), searchCmd(), statsCmd())
+	add("dns", zoneCmd(), recordCmd(), viewCmd(), aclCmd(), tsigCmd(), optionCmd(), settingsCmd(), blockCmd(), blocklistCmd(), acmeCmd(), searchCmd(), statsCmd())
 	add("changes", applyCmd(), changesetCmd(), historyCmd())
 	add("admin", statusCmd(), whoamiCmd(), userCmd(), tokenCmd(), auditCmd(), checkCmd(), resyncCmd(), configCmd())
 	setupCompletion(root)

cmd/jarl/stats.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"math"
+	"slices"
 	"strconv"
 	"strings"
 	"time"
@@ -91,6 +92,9 @@ export the data.`,
 				if s.NXDomainRatio != nil {
 					fmt.Fprintf(w, "NXDOMAIN:\t%.1f%% of queries\n", *s.NXDomainRatio*100)
 				}
+				if s.BlockedRatio != nil {
+					fmt.Fprintf(w, "Blocked:\t%d (%.1f%% of queries): %s\n", s.Blocked, *s.BlockedRatio*100, entryLine(s.Blocklists, s.Blocked, 6))
+				}
 				fmt.Fprintf(w, "Result codes:\t%s\n", entryLine(s.RCodes, s.Queries, 6))
 				fmt.Fprintf(w, "Record types:\t%s\n", entryLine(s.QTypes, s.Queries, 8))
 				if len(s.Answers) > 0 {
@@ -102,14 +106,18 @@ export the data.`,
 				if len(s.Zones) > 0 {
 					fmt.Fprintf(w, "Zones:\t%s\n", strings.ReplaceAll(entryLine(s.Zones, 0, 10), stats.OtherZone+" ", "other "))
 				}
-				for _, k := range []string{stats.KindName, stats.KindClient, stats.KindNXDomain} {
+				for _, k := range []string{stats.KindName, stats.KindClient, stats.KindNXDomain, stats.KindBlocked} {
 					es := s.Tops[k]
 					if len(es) == 0 {
 						continue
 					}
-					fmt.Fprintf(w, "\n%s\t\n", map[string]string{stats.KindName: "Top names", stats.KindClient: "Top clients", stats.KindNXDomain: "Top NXDOMAIN names"}[k])
+					fmt.Fprintf(w, "\n%s\t\n", map[string]string{stats.KindName: "Top names", stats.KindClient: "Top clients", stats.KindNXDomain: "Top NXDOMAIN names", stats.KindBlocked: "Top blocked names"}[k])
 					for _, e := range es {
-						fmt.Fprintf(w, "  %s\t%d\n", e.Key, e.Count)
+						key := e.Key
+						if e.Name != "" {
+							key += " (" + e.Name + ")"
+						}
+						fmt.Fprintf(w, "  %s\t%d\n", key, e.Count)
 					}
 				}
 			})
@@ -120,12 +128,14 @@ export the data.`,
 
 	var limit int
 	top := &cobra.Command{
-		Use:   "top [names|clients|nxdomain|servfail|refused]",
-		Short: "The most queried names, busiest clients, names with errors, refused clients",
+		Use:   "top [names|clients|nxdomain|servfail|refused|blocked|blocked-clients]",
+		Short: "The most queried names, busiest clients, names with errors, refused clients, blocked names",
 		Example: `  jarl stats top names --since 7d
   jarl stats top clients --limit 50
   jarl stats top nxdomain      # misconfigured hosts and typos
-  jarl stats top refused       # who is asking for what they may not have`,
+  jarl stats top refused       # who is asking for what they may not have
+  jarl stats top blocked       # what blocking stops most (docs/blocking.md)
+  jarl stats top blocked-clients   # the devices blocking stops most`,
 		Args: cobra.MaximumNArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
 			kind := stats.KindName
@@ -134,6 +144,9 @@ export the data.`,
 				if kind == "nxdomain" || kind == "servfail" {
 					kind = strings.ToLower(args[0])
 				}
+				if kind == "blocked-client" {
+					kind = stats.KindBlockedClient
+				}
 			}
 			c, err := newClient()
 			if err != nil {
@@ -148,14 +161,23 @@ export the data.`,
 				for _, e := range es {
 					total += e.Count
 				}
-				head := map[string]string{stats.KindClient: "CLIENT", stats.KindRefused: "CLIENT"}[kind]
+				head := map[string]string{stats.KindClient: "CLIENT", stats.KindRefused: "CLIENT", stats.KindBlockedClient: "CLIENT"}[kind]
 				if head == "" {
 					head = "NAME"
 				}
+				named := slices.ContainsFunc(es, func(e stats.Entry) bool { return e.Name != "" })
+				if named {
+					fmt.Fprintf(w, "#\t%s\tHOST\tQUERIES\t\n", head)
+				} else {
 					fmt.Fprintf(w, "#\t%s\tQUERIES\t\n", head)
+				}
 				for i, e := range es {
+					if named {
+						fmt.Fprintf(w, "%d\t%s\t%s\t%d\t%s\n", i+1, e.Key, dash(e.Name), e.Count, bar(e.Count, es[0].Count, 20))
+					} else {
 						fmt.Fprintf(w, "%d\t%s\t%d\t%s\n", i+1, e.Key, e.Count, bar(e.Count, es[0].Count, 20))
 					}
+				}
 			})
 		},
 	}

cmd/jarld/main.go

@@ -123,6 +123,10 @@ func openApp(allowMissingConfig bool) (*app, error) {
 		NoReload:      cfg.BIND.NoReload,
 		Extras:        renderExtras(cfg),
 	}, log)
+	eng.Limits = engine.BlocklistLimits{
+		Refresh: time.Duration(cfg.Blocking.Refresh), RetryAfter: time.Hour, Timeout: 2 * time.Minute,
+		MaxBytes: int64(cfg.Blocking.MaxDownloadMB) << 20, MaxEntries: cfg.Blocking.MaxEntries,
+	}
 	return &app{cfg: cfg, log: log, store: st, eng: eng, owner: owner}, nil
 }
 
@@ -323,6 +327,7 @@ func serveCmd() *cobra.Command {
 				}
 			}()
 			go auditRetention(ctx, a)
+			go blocklistLoop(ctx, a)
 			a.log.Info("jarld starting", "version", version.String(), "database", a.cfg.Database, "bind_config", a.cfg.BIND.ConfigDir)
 			err = srv.Serve(ctx, func() { sdNotify("READY=1\nSTATUS=serving") })
 			sdNotify("STOPPING=1")
@@ -332,6 +337,33 @@ func serveCmd() *cobra.Command {
 	}
 }
 
+// blocklistLoop keeps blocklists up to date (docs/blocking.md): every few
+// minutes it downloads the lists that are due, and at once when a list
+// was added or changed. It also ends a pause of blocking on time.
+func blocklistLoop(ctx context.Context, a *app) {
+	select {
+	case <-ctx.Done():
+		return
+	case <-time.After(10 * time.Second): // let jarld finish starting
+	}
+	for {
+		a.eng.RefreshDue(ctx)
+		wait := 5 * time.Minute
+		if until := a.eng.ResumeBlocking(ctx); !until.IsZero() {
+			wait = min(wait, max(time.Until(until), time.Second))
+		}
+		t := time.NewTimer(wait)
+		select {
+		case <-ctx.Done():
+			t.Stop()
+			return
+		case <-t.C:
+		case <-a.eng.BlocklistKicks():
+			t.Stop()
+		}
+	}
+}
+
 func auditRetention(ctx context.Context, a *app) {
 	if a.cfg.Audit.RetentionDays <= 0 {
 		return

docs/api.md

@@ -411,6 +411,29 @@ send the request with that changeset (`?changeset=` or
 | GET | `/tsig-keys/{id}` | `?secret=1` includes the secret (needs `tsig:write`, audited) |
 | PATCH / DELETE | `/tsig-keys/{id}` | PATCH `{"secret": "..."}` rotates |
 
+### Blocking
+
+Needs `blocking:read` (`blocking:write` to change). See
+[blocking.md](blocking.md).
+
+| Method | Path | Body / query |
+|--------|------|--------------|
+| GET | `/blocking/lists` | each with `views` (where it applies), `auto_views` (not chosen: every view that offers recursion), `state` (ok, waiting, error, disabled, idle), `status` (`entries`, `records`, `skipped`, `checked_at`, `updated_at`, `error`) and `memory_mb` (named's memory for it, estimated) |
+| POST | `/blocking/lists` | `{"name": "hagezi-multi", "url": "https://...", "views": ["internal"], "comment": ""}` (`views` empty or absent: automatic); jarld downloads it right after |
+| GET / PATCH / DELETE | `/blocking/lists/{id or name}` | PATCH any of `name`, `url`, `views`, `disabled`, `comment` |
+| POST | `/blocking/lists/{id or name}/refresh` | download now and wait; `?force=1` even when the server says nothing changed. Returns the list; a failed update is in `state` and `status.error` |
+| GET | `/blocking/rules` | each with `views` and `auto_views` |
+| POST | `/blocking/rules` | `{"name": "doubleclick.net", "action": "block", "exact": false, "views": [], "comment": ""}` (`action` block or allow; `exact`: only the name, not the names below it) |
+| PATCH / DELETE | `/blocking/rules/{id}` | |
+| DELETE | `/blocking/rules` | `?name=DOMAIN[&view=V][&missing_ok=1]`: the rules for a domain |
+| GET | `/blocking/check` | `?name=DOMAIN`: per view with blocking, `{view, result: blocked\|allowed\|none, entry, rule_id, list}` (what applies when blocking isn't paused) |
+| GET | `/blocking/status` | `{paused_until}` (null when not paused) |
+| POST | `/blocking/pause` | `{"minutes": 15}` (1 to 1440): let every name through until then; jarld resumes by itself |
+| POST | `/blocking/resume` | end a pause now |
+
+Lists and rules are configuration like the rest: they can be staged, and
+listing with `?changeset=` marks them `pending`.
+
 ### Options and settings
 
 | Method | Path | Body / query |
@@ -462,6 +485,9 @@ An **Operation** is `{"op": "...", "id": 0, "base_version": 0, "data": {...}}`:
 | `tsig.create` / `tsig.update` / `tsig.delete` | key | key fields |
 | `option.create` / `option.update` / `option.delete` | option | option fields |
 | `settings.update` | | settings fields |
+| `blocklist.create` / `blocklist.update` / `blocklist.delete` | blocklist (update/delete) | list fields; views as `views` (names) or `view_ids` |
+| `blockrule.create` / `blockrule.update` / `blockrule.delete` | rule (update/delete) | rule fields, likewise |
+| `blocking.pause` | | `{"until": "2026-10-10T15:04:05Z"}`, or `null` to resume |
 
 Operations later in a batch can refer to objects created earlier in it by
 name (zone and view names). One request can therefore create a view, a zone
@@ -471,7 +497,7 @@ in it and its records.
 
 | Method | Path | Notes |
 |--------|------|-------|
-| GET | `/status` | named status, adoption, drift, open changesets, current problems, object counts; `expiring_tokens` (tokens that expire within 14 days or expired in the last 14: all for administrators, otherwise the caller's); `backup` (administrators: `last_at`, `last_file`, `last_size`, `last_error`, `last_error_at`, `dir`, `warn_after` in seconds, `stale`) |
+| GET | `/status` | named status, adoption, drift, open changesets, current problems, object counts; `expiring_tokens` (tokens that expire within 14 days or expired in the last 14: all for administrators, otherwise the caller's); `backup` (administrators: `last_at`, `last_file`, `last_size`, `last_error`, `last_error_at`, `dir`, `warn_after` in seconds, `stale`); `blocklist_errors` (with `blocking:read`: lists whose last update failed, `{name, error, updated_at}`); `blocking_paused_until` (with `blocking:read`, while paused) |
 | POST | `/system/check` | validation + named-checkconf of the current configuration (`options:read`) |
 | POST | `/system/resync` | `{"dry_run": false, "force": false}`: rewrite every file from the database and reload (admin) |
 | GET | `/audit` | `?user=&action=&outcome=&object_type=&changeset=&q=&since=&until=&limit=200&before=ID` |
@@ -484,11 +510,11 @@ Needs `stats:read`. When statistics are disabled, every endpoint but
 | Method | Path | Query | Returns |
 |--------|------|-------|---------|
 | GET | `/stats/status` | | `{enabled, query_log, statistics_channel, log_file, last_poll, last_log_line, log_lines_read, first_data, retention, warnings}` |
-| GET | `/stats/summary` | `since` (90m, 24h, 7d, 2w; default 24h), `top` (default 10) | totals, `avg_qps`, `peak`, `rcodes`, `qtypes`, `views`, `zones`, `answers`, `transport`, `cache_hit_ratio`, `nxdomain_ratio`, `tops` |
+| GET | `/stats/summary` | `since` (90m, 24h, 7d, 2w; default 24h), `top` (default 10) | totals, `avg_qps`, `peak`, `rcodes`, `qtypes`, `views`, `zones`, `answers`, `transport`, `cache_hit_ratio`, `nxdomain_ratio` (without blocked answers), `blocked`, `blocked_ratio`, `blocklists` (blocked per list; `rules` for your rules), `tops` |
 | GET | `/stats/timeline` | `since`, `step` (auto, 1m, 5m, 15m, 1h, 6h, 1d), `key` (repeatable or comma separated; `rcode:*` = every counter of a group; default `queries`) | `{step, times: [unix...], series: [{key, values}]}` |
-| GET | `/stats/top` | `kind` (name, client, nxdomain, servfail, refused), `since`, `limit` (default 20) | `[{key, count}]` |
+| GET | `/stats/top` | `kind` (name, client, nxdomain, servfail, refused, blocked, blocked_client), `since`, `limit` (default 20) | `[{key, count}]`; client, refused and blocked_client entries add `name`, the host name of Jarl's record for the address (the summary's client list too) |
 | GET | `/stats/heatmap` | `since` (default 28d), `key` (default queries) | `{key, from, avg[7][24], samples[7][24]}`, Monday first, local time, `-1` = no data |
-| GET | `/stats/breakdown` | `group` (qtype, rcode, view, zone, answer, transport, rtt, dnssec, cache, ratelimit), `since` | `[{key, count}]` |
+| GET | `/stats/breakdown` | `group` (qtype, rcode, view, zone, answer, transport, rtt, dnssec, cache, ratelimit, blocklist), `since` | `[{key, count}]` |
 
 ```sh
 curl -sf -H "$AUTH" "$API/stats/top?kind=nxdomain&since=7d&limit=10" | jq -r '.[] | "\(.count)\t\(.key)"'

docs/blocking.md

@@ -0,0 +1,264 @@
+# Blocking
+
+Jarl can make named answer "this name doesn't exist" (NXDOMAIN) for ads,
+trackers and malware, like Pi-hole does, for every device that uses your
+server to resolve names. It has two parts:
+
+- **Blocklists**: lists of domains published by others, which jarld
+  downloads and keeps up to date.
+- **Your rules**: domains you block or allow yourself. They take precedence
+  over every list.
+
+It uses BIND's own mechanism for this, response policy zones (RPZ), so named
+does the blocking itself; jarld only prepares the lists.
+
+- [Quick start](#quick-start)
+- [Where blocking applies](#where-blocking-applies)
+- [Your rules](#your-rules)
+- [Blocklists](#blocklists)
+- [Checking a name](#checking-a-name)
+- [Pausing](#pausing)
+- [Statistics](#statistics)
+- [Memory and performance](#memory-and-performance)
+- [How it works](#how-it-works)
+- [Troubleshooting](#troubleshooting)
+
+## Quick start
+
+In the web UI, open **Blocking**, pick one of the well-known lists, and
+click **Add list**. Or with the CLI:
+
+```sh
+jarl blocklist add hagezi-multi https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/multi.txt
+jarl blocklist list                     # "ok" once downloaded, usually within seconds
+jarl block check ads.doubleclick.net    # blocked? by what?
+jarl block allow cdn.example.com        # something you need was blocked
+```
+
+Like every change in Jarl, adding a list or rule can be staged and reviewed
+first (the web UI does this by default: apply it under **Changes**).
+
+## Where blocking applies
+
+Blocking changes the answers named gives when it resolves names for a
+client (recursion). It doesn't change what the internet sees of your own
+zones: other resolvers ask your server without recursion.
+
+**Views.** A list or rule applies to the views you choose, or by default
+to every view that offers recursion. With the usual split (an `internal`
+view that resolves for your network, an `external` view that only answers
+for your zones) that is just `internal`. A view that doesn't offer
+recursion gets nothing, and naming one gives a warning. Without views,
+blocking applies to the whole server.
+
+**What it can't do:**
+
+- Devices that don't use your server for DNS aren't affected. That includes
+  browsers using their own DNS over HTTPS, and devices with a hard-coded
+  resolver (8.8.8.8). A firewall rule that sends port 53 to your server, and
+  your network's DNS settings, are the usual answers.
+- A device that validates DNSSEC itself sees a blocked name as a
+  validation failure rather than "doesn't exist". It's still blocked.
+- A list can contain names in your own zones. They are blocked like any
+  other; allow them with a rule if that's not what you want.
+
+## Your rules
+
+A rule **blocks** or **allows** a domain and every name below it, or with
+`--exact` (web UI: "only this exact name") just the domain itself.
+
+```sh
+jarl block add doubleclick.net                       # doubleclick.net and everything below it
+jarl block add telemetry.example.com --exact         # just that name
+jarl block allow cdn.example.com --view internal     # an exception, in one view
+jarl block list
+jarl block delete doubleclick.net                    # or: --id ID
+```
+
+**Precedence:** your rules come before every blocklist, and among your
+rules the most specific one wins. With these rules:
+
+| Rule | |
+|------|-|
+| block `example.com` | and below |
+| allow `cdn.example.com` | exact |
+
+`example.com` and `www.example.com` are blocked, `cdn.example.com` is
+allowed, and `img.cdn.example.com` is blocked again (the allow rule was for
+the exact name). An allow rule beats a blocklist entry whatever the lists
+say.
+
+There is one rule per domain and view; a second one is refused. A rule
+takes effect as soon as the change is applied.
+
+## Blocklists
+
+**Formats.** Lists are read line by line; one list may mix formats:
+
+| Line | Blocks |
+|------|--------|
+| `\|\|ads.example^` (Adblock) | the name and every name below it |
+| `*.ads.example` | the name and every name below it |
+| `0.0.0.0 ads.example` (hosts file, any address) | just the name |
+| `ads.example` (plain domain) | just the name |
+
+Comments (`#`, `!`), headers and blank lines are ignored. Lines that DNS
+can't act on are skipped and counted: Adblock exceptions (`@@`), cosmetic
+and URL rules, addresses, invalid names, and single labels (a broken list
+can't block `com`). Prefer lists in Adblock format: they say which entries
+cover the names below them.
+
+**Well-known lists** (sizes in October 2026; they change):
+
+| List | URL | Domains | Memory per view |
+|------|-----|--------:|----------------:|
+| Hagezi Light | `https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/light.txt` | 55,000 | ~65 MB |
+| Hagezi Multi Normal | `https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/multi.txt` | 159,000 | ~190 MB |
+| Hagezi Pro | `https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/pro.txt` | 195,000 | ~235 MB |
+| OISD Small | `https://small.oisd.nl/` | 58,000 | ~70 MB |
+| OISD Big | `https://big.oisd.nl/` | 241,000 | ~290 MB |
+| StevenBlack hosts | `https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts` | 73,000 | ~45 MB |
+
+One good list is usually enough; lists overlap a lot. Hagezi Multi Normal
+is a balanced start; Light and OISD Small block less but almost never
+something you need.
+
+**Updates.** jarld checks each list every `blocking.refresh` (a day by
+default) and downloads it only when the server says it changed. A new
+version is checked with `named-checkzone` and replaces the old one only
+when its content differs; named then reloads it. If a download or check
+fails, named keeps using the previous version, jarld tries again within
+the hour, and the dashboard shows the error. To update now:
+
+```sh
+jarl blocklist refresh              # every list; or: refresh hagezi-multi [--force]
+```
+
+**Managing lists:**
+
+```sh
+jarl blocklist update hagezi-multi --view internal     # --view auto: every view with recursion
+jarl blocklist update hagezi-multi --url URL --name NEW-NAME
+jarl blocklist disable hagezi-multi                    # stop using it, keep it (enable: back without a download)
+jarl blocklist delete hagezi-multi
+```
+
+A list's state is **ok** (in use), **waiting** (not downloaded yet),
+**error** (the last update failed; the previous version stays in use),
+**disabled**, or **idle** (it applies to no view, so it does nothing).
+
+## Checking a name
+
+`jarl block check NAME`, or the box at the top of the Blocking page, says
+for each view whether a name is blocked or allowed, and by which rule or
+list entry:
+
+```
+$ jarl block check img.ads.example.com
+view internal:  blocked by blocklist hagezi-multi (entry *.ads.example.com)
+view guest:     allowed by your rule 12 (entry *.ads.example.com)
+```
+
+Views without blocking aren't listed.
+
+In the web UI a blocked name gets an **Allow** button, and the statistics'
+most blocked names link to this check.
+
+## Pausing
+
+To see whether blocking is what breaks a site, pause it: every name is
+answered normally until the time is up (at most a day), then blocking
+resumes by itself, also if jarld was restarted in between.
+
+```sh
+jarl block pause          # 10 minutes; or: jarl block pause 1h
+jarl block resume         # end it now
+```
+
+In the web UI, **Pause blocking** is at the top of the Blocking page, and
+the dashboard says while blocking is paused. The lists stay loaded (the
+rules zone just lets everything through), so pausing and resuming take
+effect within a second. Pausing and resuming are recorded in the history
+like other changes.
+
+## Statistics
+
+With [query statistics](stats.md) on (including `query_log`), Jarl counts
+what blocking does: blocked queries over time (next to all queries) and
+as a share of them, which rules and lists blocked them, the most blocked
+names, and the clients with the most blocked queries (`jarl stats summary`,
+`jarl stats top blocked`, `jarl stats top blocked-clients`, `jarl stats
+breakdown blocklist`). Blocked answers are left out of the NXDOMAIN figures, which
+are about names that really don't exist.
+
+Without statistics named doesn't log what it blocks at all.
+
+## Memory and performance
+
+**Memory** is the cost to watch. named keeps each list in memory, once per
+view it applies to: about 0.6 KB per policy record (an Adblock entry is
+two records: the name, and the names below it). The Blocking page and
+`jarl blocklist list` show the estimate per list. Hagezi Pro in one view
+took named from 25 MB to 260 MB in a test with BIND 9.20; while a list
+reloads, the old and new versions briefly coexist.
+
+**Answers aren't slowed**: named looks blocked names up in memory, and
+answers them without asking the internet.
+
+**Updating a list** (Hagezi Pro: download, parse, check) takes jarld about
+2 seconds. While named loads the new version, the queries that the loading
+thread would have answered wait, up to half a second; this only happens
+when the list changed, at most once per `blocking.refresh`.
+
+**Other changes are unaffected**: the lists' contents never go through
+Jarl's apply, so adding a record takes as long with a list as without.
+
+Downloads are limited by `blocking.max_download_mb` and
+`blocking.max_entries` ([configuration.md](configuration.md#blocking)).
+
+## How it works
+
+For each view (or the server, without views) Jarl writes a
+`response-policy` statement and the policy zones it lists, in this order:
+
+```
+response-policy {
+	zone "rules.jarl.invalid" min-update-interval 0;              # your rules
+	zone "hagezi-multi.blocklist.jarl.invalid" min-update-interval 0;
+} qname-wait-recurse no break-dnssec yes;
+```
+
+- Policy zones are named under `.invalid`, so they can't clash with real
+  zones (zone names under `jarl.invalid` are refused). They allow no
+  queries or transfers.
+- The rules zone of each view is a file next to your zone files
+  (`/var/lib/bind/jarl/VIEW/rules.jarl.invalid.rpz`) and shows up in the
+  changeset diff like any other.
+- A list's file is `/var/cache/bind/jarl/blocklists/list-ID.rpz`, shared by
+  the views that use it. Until the first download it is an empty policy
+  zone, so named always starts. Files of deleted lists are removed.
+- `qname-wait-recurse no` blocks without first resolving the real answer;
+  `break-dnssec yes` also blocks for clients that ask for DNSSEC data;
+  `min-update-interval 0` applies a new version at once.
+- named looks names up in a policy zone like in any zone, so a wildcard
+  doesn't apply below a name the zone also contains. Jarl writes the zones
+  so that the most specific rule still wins.
+- A `response-policy` option of your own can't be combined with Jarl's
+  blocking in the same view: Jarl refuses the change and says so.
+- Rewrites are logged to Jarl's response log when statistics read it, and
+  not at all otherwise.
+
+Lists and rules need the `blocking` permission ([permissions.md](permissions.md)).
+
+## Troubleshooting
+
+- **"no domains found in N lines"**: the URL didn't return a list (often an
+  HTML error page). Check it in a browser.
+- **A list has no effect / is "idle"**: no view it applies to offers
+  recursion. Pick the view your devices use (`--view internal`).
+- **Something is still answered**: `jarl block check NAME` shows whether
+  Jarl blocks it. If it does, the device probably doesn't use your server
+  (DNS over HTTPS, another resolver), or has the answer cached for a
+  while.
+- **Something you need is blocked**: `jarl block check NAME` shows which
+  list; `jarl block allow NAME` overrides it.

docs/cli.md

@@ -419,15 +419,35 @@ working.
 ```sh
 jarl stats status
 jarl stats summary --since 7d
-jarl stats top names | clients | nxdomain | servfail | refused [--since 24h] [--limit 20]
+jarl stats top names | clients | nxdomain | servfail | refused | blocked | blocked-clients [--since 24h] [--limit 20]
 jarl stats timeline --since 6h [--key rcode:NXDOMAIN] [--table]
 jarl stats heatmap --since 28d
-jarl stats breakdown qtype | rcode | view | zone | answer | rtt
+jarl stats breakdown qtype | rcode | view | zone | answer | rtt | blocklist
 ```
 
 Statistics must be enabled in `jarl.yaml`, and `-o json` exports the data.
 See [stats.md](stats.md).
 
+## Blocking
+
+```sh
+jarl blocklist list
+jarl blocklist add NAME URL [--view V]...         # default: every view that offers recursion
+jarl blocklist update NAME [--url U] [--name N] [--view V | --view auto] [--comment C]
+jarl blocklist disable | enable | delete NAME
+jarl blocklist refresh [NAME...] [--force]       # download now (all lists without NAME)
+
+jarl block add DOMAIN [--exact] [--view V]...    # block it (and the names below it)
+jarl block allow DOMAIN [--exact] [--view V]...  # an exception that beats every list
+jarl block list
+jarl block delete DOMAIN [--view V] | --id ID
+jarl block check DOMAIN                          # blocked? by which rule or list?
+jarl block pause [DURATION]                      # let everything through for a while (default 10m, at most 24h)
+jarl block resume
+```
+
+See [blocking.md](blocking.md).
+
 ## ACME DNS-01
 
 ```sh

docs/configuration.md

@@ -134,6 +134,17 @@ jarl.yaml; chmod 640 jarl.yaml`, as the Debian package installs it); jarld
 warns at start when everyone can read it. At porkbun.com, switch on "API
 Access" for the domain, and limit the key to the domain if you can.
 
+### Blocking
+
+How jarld downloads blocklists ([blocking.md](blocking.md)). The lists and
+rules themselves are configuration in the database.
+
+| Key | Default | Meaning |
+|-----|---------|---------|
+| `blocking.refresh` | `24h` | How often each blocklist is checked for changes (at least `1h`); it is downloaded only when it changed ([blocking.md](blocking.md)). |
+| `blocking.max_download_mb` | `64` | Larger downloads are refused (the previous version stays in use). |
+| `blocking.max_entries` | `1000000` | Lists with more domains are refused. |
+
 ## Example: management network with TLS
 
 ```yaml

docs/development.md

@@ -28,6 +28,8 @@ internal/
   nscheck/            DNS queries to other name servers: zone serials, the parent's delegation and DS records
   dnssec/             reads named's DNSSEC key and state files; DS records; the signing phases (docs/dnssec.md)
   porkbun/            Porkbun API client (name servers, glue, DS records) and an in-memory fake for tests
+  blocking/           blocklist parser, response policy zone writers, and matching a name the way named does
+                      (the downloads are in engine/blocklists.go)
   config/             jarld's YAML configuration
 deploy/               systemd units (jarld, the daily backup service and timer), sysusers.d and tmpfiles.d files
 deploy/debian/        the Debian package's control template and postinst/prerm/postrm

docs/permissions.md

@@ -135,6 +135,7 @@ RESOURCE:ACCESS [zones=PATTERNS] [views=PATTERNS] [names=PATTERNS] [types=TYPES]
 | `options` | server options, top-level statements, the defaults for new zones, `jarl check` |
 | `audit` | everyone's audit events and changesets (without it, users see only their own) |
 | `stats` | query statistics, including client addresses and the names they look up (read only) |
+| `blocking` | blocklists and block/allow rules ([blocking.md](blocking.md)); `write` also downloads lists now |
 | `*` | all of the above |
 
 `ACCESS` is `read` or `write` (write includes read). Filters narrow a grant.
@@ -168,7 +169,7 @@ you can then edit.
 | Role | Grants |
 |------|--------|
 | `readonly` | `*:read` (includes statistics) |
-| `dns-editor` | `zones:write`, `records:write`, `views:read`, `acls:read`, `options:read` |
+| `dns-editor` | `zones:write`, `records:write`, `views:read`, `acls:read`, `options:read`, `blocking:read` |
 | `operator` | `*:write` (everything except user management) |
 | `acme` | `records:write names=_acme-challenge.* types=TXT` |
 

docs/stats.md

@@ -102,15 +102,29 @@ lists, views, zones). named's own counters can't be filtered.
 | `view:NAME` | response log | answers per view (`_default` without views) |
 | `zone:NAME` | response log | answers per local zone; `zone:-` for names in none of your zones |
 | `responses` | response log | lines read (a health check) |
+| `blocked`, `blocklist:NAME` | response log | queries [blocking](blocking.md) answered, and by which list (`blocklist:rules` for your own rules) |
 
 **Top lists** (per hour and per day, the `top_n` largest): `name` (most
 queried names), `client`, `nxdomain` (names answered NXDOMAIN), `servfail`
-(names answered SERVFAIL), `refused` (clients that were refused).
+(names answered SERVFAIL), `refused` (clients that were refused), `blocked`
+(names blocking answered), `blocked_client` (clients by blocked queries). Blocked answers are NXDOMAIN too, but they
+aren't counted as names that don't exist: not in the `nxdomain` list, and
+not in the summary's NXDOMAIN ratio.
 
 Nothing else is stored. In particular there's no per-query record, so you
 can't look up "who asked for X at 14:02". That is deliberate, both for size
 and privacy.
 
+**Client names.** Where the client lists (busiest and refused clients) show
+an address Jarl has a record for, they show its host name too: the PTR
+record's target, or else the name of an A/AAAA record with that address
+(disabled records don't count, and only records you may read). This is
+looked up in Jarl's own data when the list is shown, not stored and not
+asked of DNS, so it is instant and adds no queries of its own. The name is
+what the records say now: with DHCP, an address seen last week may have
+been another machine. Anonymized clients (`anonymize_clients`) are
+prefixes and get no name.
+
 ## Using it
 
 **Web UI**: Statistics. Pick a range (1 hour to 90 days); everything on the

docs/validation.md

@@ -30,6 +30,7 @@ showing them.
 | `record_out_of_zone` | error | The name must be inside the zone (catches `www.example.com` without the final dot) |
 | `record_duplicate` | error | The same record can't exist twice |
 | `cname_conflict` | error | A CNAME must be the only record at its name (RFC 1034), so no CNAME next to A, MX, TXT... |
+| `disabled_conflict` | warning | A disabled record that couldn't be enabled again as the zone is now (a CNAME now shares its name) |
 | `cname_multiple` | error | A name can have only one CNAME |
 | `cname_apex` | error | No CNAME at the zone apex (it needs SOA and NS) |
 | `cname_loop` | error | CNAMEs that point back to themselves |
@@ -100,6 +101,19 @@ applied.
 | `dnssec_old_keys` | info | Signing a zone whose key directory still has old keys |
 | `serial_not_higher` | error | An explicit serial on a signed zone must be above the one named has loaded (automatic serials are raised by themselves) |
 
+## Blocking
+
+From [blocking.md](blocking.md).
+
+| Code | Severity | Rule |
+|------|----------|------|
+| `blocking_rule_duplicate` | error | One rule per domain and view |
+| `blocking_response_policy` | error | No `response-policy` option where Jarl's blocking writes that statement (the view, or the server) |
+| `zone_name_reserved` | error | Zone names under `jarl.invalid` are reserved for blocking's policy zones |
+| `blocking_view_missing` | error | A list or rule names a view that doesn't exist |
+| `blocking_no_view` | warning | A list or rule applies to no view: none offers recursion, and blocking only changes recursive answers |
+| `blocking_no_recursion` | warning | A list or rule names a view that doesn't offer recursion, where it has no effect |
+
 ## Security lints
 
 | Code | Severity | What it catches |

internal/api/types.go

@@ -77,6 +77,10 @@ type Option struct {
 	Where       string `json:"where"` // e.g. "view internal"
 	Description string `json:"description,omitempty"`
 	Status      string `json:"status,omitempty"`
+	// Formatted is the value laid out over several lines, as in
+	// named.conf, when it has a block (for display and editing; Value is
+	// the same on one line).
+	Formatted string `json:"formatted,omitempty"`
 }
 
 // User is a user with formatted grants.
@@ -242,6 +246,19 @@ type StatusResponse struct {
 	Backup *BackupStatus `json:"backup,omitempty"`
 	// TOTP is about two-factor login across users (administrators only).
 	TOTP *TOTPOverview `json:"totp,omitempty"`
+	// BlocklistErrors are blocklists whose last update failed (for those
+	// who may see blocking).
+	BlocklistErrors []BlocklistError `json:"blocklist_errors,omitempty"`
+	// BlockingPausedUntil is set while blocking is paused.
+	BlockingPausedUntil *time.Time `json:"blocking_paused_until,omitempty"`
+}
+
+// BlocklistError is a blocklist whose last update failed. UpdatedAt is
+// the version named keeps using (nil: none yet).
+type BlocklistError struct {
+	Name      string     `json:"name"`
+	Error     string     `json:"error"`
+	UpdatedAt *time.Time `json:"updated_at,omitempty"`
 }
 
 // TOTPOverview is what the dashboard reports about two-factor login.
@@ -471,3 +488,28 @@ type RegistrarChangeResponse struct {
 	Checks   []nscheck.Finding `json:"checks"`
 	Warnings []string          `json:"warnings"`
 }
+
+// Blocklist is a blocklist as returned by the API (docs/blocking.md).
+type Blocklist struct {
+	model.Blocklist
+	// Views are the views it applies to; AutoViews is set when that is
+	// "every view that offers recursion" (view_ids is empty).
+	Views     []string `json:"views"`
+	AutoViews bool     `json:"auto_views,omitempty"`
+	// State is ok, waiting (not downloaded yet), error (the last update
+	// failed; the previous version stays in use), disabled, or idle (it
+	// applies to no view).
+	State  string                 `json:"state"`
+	Status *model.BlocklistStatus `json:"status,omitempty"`
+	// MemoryMB estimates what named needs for the list, in all its views.
+	MemoryMB int    `json:"memory_mb,omitempty"`
+	Pending  string `json:"pending,omitempty"`
+}
+
+// BlockRule is a block or allow rule as returned by the API.
+type BlockRule struct {
+	model.BlockRule
+	Views     []string `json:"views"`
+	AutoViews bool     `json:"auto_views,omitempty"`
+	Pending   string   `json:"pending,omitempty"`
+}

internal/auth/grants.go

@@ -20,11 +20,12 @@ const (
 	ResOptions  = "options"  // server options, top-level statements, settings
 	ResAudit    = "audit"    // audit log and everyone's changesets
 	ResStats    = "stats"    // query statistics
+	ResBlocking = "blocking" // blocklists and block/allow rules
 	ResAll      = "*"
 )
 
 // Resources lists the resources in display order.
-var Resources = []string{ResZones, ResRecords, ResViews, ResACLs, ResTSIG, ResOptions, ResAudit, ResStats}
+var Resources = []string{ResZones, ResRecords, ResViews, ResACLs, ResTSIG, ResOptions, ResAudit, ResStats, ResBlocking}
 
 // Access levels.
 const (
@@ -377,6 +378,7 @@ var RoleTemplates = map[string][]model.Grant{
 		{Resource: ResViews, Access: Read},
 		{Resource: ResACLs, Access: Read},
 		{Resource: ResOptions, Access: Read},
+		{Resource: ResBlocking, Access: Read},
 	},
 	"operator": {{Resource: ResAll, Access: Write}},
 	"acme":     {{Resource: ResRecords, Access: Write, Names: []string{"_acme-challenge.*"}, Types: []string{"TXT"}}},

internal/blocking/blocking_test.go

@@ -0,0 +1,180 @@
+package blocking
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestParse(t *testing.T) {
+	src := "\uFEFF[Adblock Plus]\r\n" + `! Title: test list
+# a comment
+
+||ads.example^
+||Tracker.Example.^$important
+||cosmetic.example^$third-party
+@@||allowed.example^
+example.org##.banner
+|https://url.example/path
+0.0.0.0 hosts.example other.example  # two names
+127.0.0.1 localhost
+127.0.0.1 localhost.localdomain
+::1 ip6-localhost
+0.0.0.0 0.0.0.0
+plain.example
+*.wild.example
+single
+1.2.3.4
+bad_label!.example
+münchen.example
+www.ads.example
+` + strings.Repeat("a", 64) + ".example\n"
+	l, err := Parse(strings.NewReader(src), Limits{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := map[string]uint8{
+		"ads.example": Exact | Below, "tracker.example": Exact | Below,
+		"hosts.example": Exact, "other.example": Exact, "plain.example": Exact,
+		"wild.example": Exact | Below, "xn--mnchen-3ya.example": Exact, "www.ads.example": Exact,
+	}
+	if len(l.Domains) != len(want) {
+		t.Errorf("domains = %v", l.Domains)
+	}
+	for n, f := range want {
+		if l.Domains[n] != f {
+			t.Errorf("%s = %d, want %d", n, l.Domains[n], f)
+		}
+	}
+	// Skipped: $third-party, @@, ##, |url, localhost (x3), 0.0.0.0, single, 1.2.3.4, bad_label!, 64-char label.
+	if l.Skipped != 12 || l.Lines != 19 {
+		t.Errorf("lines %d, skipped %d", l.Lines, l.Skipped)
+	}
+
+	Compact(l)
+	if _, ok := l.Domains["www.ads.example"]; ok {
+		t.Error("www.ads.example is covered by ||ads.example^ and should be dropped")
+	}
+	var sb strings.Builder
+	n, hash, err := FeedZone(&sb, "test", 7, l)
+	if err != nil || n != 10 {
+		t.Fatalf("FeedZone: %d records, %v", n, err)
+	}
+	for _, line := range []string{"ads.example\tCNAME\t.\n", "*.ads.example\tCNAME\t.\n", "plain.example\tCNAME\t.\n", "@\tSOA\tlocalhost. hostmaster.localhost. 7 "} {
+		if !strings.Contains(sb.String(), line) {
+			t.Errorf("zone lacks %q:\n%s", line, sb.String())
+		}
+	}
+	if strings.Contains(sb.String(), "*.plain.example") || strings.Contains(sb.String(), "$ORIGIN") {
+		t.Errorf("zone:\n%s", sb.String())
+	}
+	// The hash ignores the serial.
+	var other strings.Builder
+	if _, h2, _ := FeedZone(&other, "test", 8, l); h2 != hash {
+		t.Error("hash depends on the serial")
+	}
+}
+
+func TestParseLimits(t *testing.T) {
+	_, err := Parse(strings.NewReader("a.example\nb.example\na.example\nc.example\n"), Limits{MaxEntries: 2})
+	if !errors.Is(err, ErrTooManyEntries) {
+		t.Errorf("err = %v", err)
+	}
+	if _, err := Parse(strings.NewReader("a.example\nb.example\na.example\n"), Limits{MaxEntries: 2}); err != nil {
+		t.Errorf("a repeated name counted against the limit: %v", err)
+	}
+	l, _ := Parse(strings.NewReader("long-name.example\nshort.example\n"), Limits{MaxNameLen: 15})
+	if len(l.Domains) != 1 || l.Skipped != 1 {
+		t.Errorf("max name length: %v", l.Domains)
+	}
+}
+
+func TestRuleEntries(t *testing.T) {
+	rules := []Rule{
+		{Name: "ads.example", Action: ActionBlock},                        // and everything below
+		{Name: "cdn.ads.example", Action: ActionAllow, Exact: true},       // just this name
+		{Name: "wide.example", Action: ActionBlock},                       // and below
+		{Name: "ok.wide.example", Action: ActionAllow},                    // and below
+		{Name: "deep.x.y.wide.example", Action: ActionAllow, Exact: true}, // two empty names in between
+		{Name: "solo.example", Action: ActionBlock, Exact: true},
+	}
+	e := RuleEntries(rules)
+	for name, want := range map[string]string{
+		"ads.example":                 ActionBlock,
+		"x.ads.example":               ActionBlock,
+		"cdn.ads.example":             ActionAllow,
+		"y.cdn.ads.example":           ActionBlock, // the wildcard above still applies
+		"ok.wide.example":             ActionAllow,
+		"a.ok.wide.example":           ActionAllow,
+		"y.wide.example":              ActionBlock, // exists only because of a deeper rule
+		"x.y.wide.example":            ActionBlock,
+		"z.x.y.wide.example":          ActionBlock,
+		"deep.x.y.wide.example":       ActionAllow,
+		"below.deep.x.y.wide.example": ActionBlock,
+		"solo.example":                ActionBlock,
+		"other.example":               "",
+		"sub.solo.example":            "",
+		"example":                     "",
+		"unrelated.org":               "",
+	} {
+		_, act, ok := MatchRules(e, name)
+		if !ok {
+			act = ""
+		}
+		if act != want {
+			t.Errorf("%s: %q, want %q", name, act, want)
+		}
+	}
+	z := RulesZoneFile("rules", rules)
+	if !strings.Contains(z, "cdn.ads.example\tCNAME\trpz-passthru.\n*.cdn.ads.example\tCNAME\t.\n") {
+		t.Errorf("rules zone:\n%s", z)
+	}
+	if strings.Index(z, "ads.example\t") > strings.Index(z, "*.ads.example\t") {
+		t.Errorf("a name should come before its wildcard:\n%s", z)
+	}
+}
+
+func TestMatchFeed(t *testing.T) {
+	l, _ := Parse(strings.NewReader("||tracker.example^\nexact.example\n||deep.a.example^\n"), Limits{})
+	Compact(l)
+	path := filepath.Join(t.TempDir(), "list.rpz")
+	f, _ := os.Create(path)
+	FeedZone(f, "t", 1, l)
+	f.Close()
+	for name, want := range map[string]string{
+		"tracker.example":     "tracker.example",
+		"a.b.tracker.example": "*.tracker.example",
+		"exact.example":       "exact.example",
+		"sub.exact.example":   "",
+		"x.deep.a.example":    "*.deep.a.example",
+		"a.example":           "",
+		"example":             "",
+	} {
+		owner, ok, err := MatchFeed(path, name)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !ok {
+			owner = ""
+		}
+		if owner != want {
+			t.Errorf("%s: %q, want %q", name, owner, want)
+		}
+	}
+}
+
+func TestNames(t *testing.T) {
+	if ListZone("hagezi") != "hagezi.blocklist.jarl.invalid" || ListName("hagezi.blocklist.jarl.invalid.") != "hagezi" || ListName(RulesZone) != "" || ListName("x.y.blocklist.jarl.invalid") != "" {
+		t.Error("zone names")
+	}
+	if n, err := NormalizeName("Ads.Example.COM."); err != nil || n != "ads.example.com" {
+		t.Errorf("NormalizeName = %q, %v", n, err)
+	}
+	for _, bad := range []string{"com", "1.2.3.4", "a b.example", "*.example.com", ""} {
+		if _, err := NormalizeName(bad); err == nil {
+			t.Errorf("%q accepted", bad)
+		}
+	}
+}

internal/blocking/parse.go

@@ -0,0 +1,198 @@
+// Package blocking turns blocklists and block/allow rules into BIND
+// response policy zones (RPZ), and answers which rule or list matches a
+// name.
+//
+// A policy zone holds one rule per owner name: "ads.example CNAME ."
+// answers NXDOMAIN for ads.example, "*.ads.example CNAME ." for every name
+// below it, and "CNAME rpz-passthru." answers normally (an exception).
+// named looks names up in a policy zone like in any zone, so wildcards
+// follow DNS rules: a wildcard doesn't apply below a name that exists in
+// the zone. The writers here add the rules that keep "the most specific
+// rule wins" true despite that (see RulesZone).
+package blocking
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"net/netip"
+	"strings"
+	"unicode/utf8"
+
+	"jarl/internal/dnsname"
+)
+
+// Flags say what a list entry covers.
+const (
+	Exact uint8 = 1 << iota // the name itself
+	Below                   // every name below it
+)
+
+// List is a parsed blocklist.
+type List struct {
+	// Domains maps names (lowercase, without the final dot) to flags.
+	Domains map[string]uint8
+	// Lines is the number of lines with an entry (not comments or blank
+	// lines); Skipped how many of them were not usable.
+	Lines, Skipped int
+}
+
+// Limits bound what Parse accepts.
+type Limits struct {
+	MaxEntries int // distinct domains (0: no limit)
+	MaxNameLen int // longest name in characters (0: 253)
+}
+
+// ErrTooManyEntries is returned when a list has more than MaxEntries
+// domains.
+var ErrTooManyEntries = errors.New("too many entries")
+
+// Parse reads a blocklist. Each line is one of:
+//
+//	||ads.example^          Adblock style: the name and everything below it
+//	*.ads.example           the name and everything below it
+//	0.0.0.0 ads.example     hosts file (any address; several names allowed)
+//	ads.example             just this name
+//
+// Comments (#, !), Adblock headers ([Adblock Plus]) and blank lines are
+// ignored. Lines that can't be used for DNS blocking (exceptions,
+// cosmetic and URL rules, addresses, single-label names, invalid names)
+// are counted as skipped.
+func Parse(r io.Reader, lim Limits) (*List, error) {
+	maxLen := lim.MaxNameLen
+	if maxLen <= 0 || maxLen > 253 {
+		maxLen = 253
+	}
+	l := &List{Domains: map[string]uint8{}}
+	full := false // a new name was refused because of MaxEntries
+	add := func(name string, flags uint8) bool {
+		name, ok := normalize(name, maxLen)
+		if !ok {
+			return false
+		}
+		if _, seen := l.Domains[name]; !seen && lim.MaxEntries > 0 && len(l.Domains) >= lim.MaxEntries {
+			full = true
+			return false
+		}
+		l.Domains[name] |= flags
+		return true
+	}
+	sc := bufio.NewScanner(r)
+	sc.Buffer(make([]byte, 64*1024), 1024*1024)
+	first := true
+	for sc.Scan() {
+		line := sc.Text()
+		if first {
+			line = strings.TrimPrefix(line, "\uFEFF")
+			first = false
+		}
+		line = strings.TrimSpace(line)
+		if line == "" || line[0] == '#' || line[0] == '!' || line[0] == '[' {
+			continue
+		}
+		l.Lines++
+		ok := false
+		switch {
+		case strings.HasPrefix(line, "||"):
+			ok = add(adblockDomain(line[2:]), Exact|Below)
+		case strings.ContainsAny(line, "|/$^@") || strings.Contains(line, "##"):
+			// Exceptions (@@), URL and cosmetic rules: not for DNS.
+		default:
+			if i := strings.Index(line, "#"); i >= 0 {
+				line = strings.TrimSpace(line[:i])
+			}
+			fields := strings.Fields(line)
+			switch {
+			case len(fields) == 1 && strings.HasPrefix(fields[0], "*."):
+				ok = add(fields[0][2:], Exact|Below)
+			case len(fields) == 1:
+				ok = add(fields[0], Exact)
+			case len(fields) > 1 && isAddr(fields[0]):
+				for _, f := range fields[1:] {
+					if add(f, Exact) {
+						ok = true
+					}
+				}
+			}
+		}
+		if full {
+			return l, fmt.Errorf("%w: the list has more than %d domains", ErrTooManyEntries, lim.MaxEntries)
+		}
+		if !ok {
+			l.Skipped++
+		}
+	}
+	if err := sc.Err(); err != nil {
+		return l, err
+	}
+	return l, nil
+}
+
+// adblockDomain returns the domain of an Adblock rule's body
+// ("ads.example^" or "ads.example^$important"), or "" when the rule
+// does more than block a domain (other modifiers, paths, wildcards).
+func adblockDomain(s string) string {
+	d, rest, _ := strings.Cut(s, "^")
+	if rest != "" && rest != "$important" {
+		return ""
+	}
+	if strings.ContainsAny(d, "*/:|$") {
+		return ""
+	}
+	return d
+}
+
+func isAddr(s string) bool {
+	_, err := netip.ParseAddr(s)
+	return err == nil
+}
+
+// localNames are hosts-file names that aren't blocklist entries.
+var localNames = map[string]bool{"localhost.localdomain": true, "ip6-localhost": true, "ip6-loopback": true}
+
+// normalize lowercases a name, removes the final dot, converts
+// international names to their ASCII form, and checks it is usable: at
+// least two labels of letters, digits, hyphens and underscores, and not an
+// address.
+func normalize(name string, maxLen int) (string, bool) {
+	name = strings.TrimSuffix(strings.ToLower(strings.TrimSpace(name)), ".")
+	if name == "" || localNames[name] || isAddr(name) {
+		return "", false
+	}
+	for i := 0; i < len(name); i++ {
+		if name[i] >= utf8.RuneSelf {
+			a, err := dnsname.ToASCII(name)
+			if err != nil {
+				return "", false
+			}
+			name = strings.TrimSuffix(strings.ToLower(a), ".")
+			break
+		}
+	}
+	if len(name) > maxLen || !strings.Contains(name, ".") {
+		return "", false
+	}
+	for _, label := range strings.Split(name, ".") {
+		if label == "" || len(label) > 63 {
+			return "", false
+		}
+		for i := 0; i < len(label); i++ {
+			c := label[i]
+			if !(c >= 'a' && c <= 'z' || c >= '0' && c <= '9' || c == '-' || c == '_') {
+				return "", false
+			}
+		}
+	}
+	return name, true
+}
+
+// NormalizeName checks and normalizes a domain the way list entries are
+// (for rules entered by hand). The name must have at least two labels.
+func NormalizeName(name string) (string, error) {
+	n, ok := normalize(name, 253-len(RulesZone)-2)
+	if !ok {
+		return "", fmt.Errorf("%q is not a domain name that can be blocked (it needs at least two labels of letters, digits, hyphens or underscores, like ads.example.com)", name)
+	}
+	return n, nil
+}

internal/blocking/zone.go

@@ -0,0 +1,313 @@
+package blocking
+
+import (
+	"bufio"
+	"crypto/sha256"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"strings"
+)
+
+// Policy zone names. They are under .invalid (RFC 6761), so they can
+// never clash with a real zone, and named only uses them internally.
+const (
+	// RulesZone holds the rules entered in Jarl (one copy per view).
+	RulesZone = "rules.jarl.invalid"
+	// listSuffix follows a list's name: hagezi.blocklist.jarl.invalid.
+	listSuffix = ".blocklist.jarl.invalid"
+)
+
+// ListZone returns the policy zone name of a blocklist.
+func ListZone(name string) string { return name + listSuffix }
+
+// ListName returns the blocklist name of a policy zone ("" for the rules
+// zone and zones that aren't Jarl's).
+func ListName(zone string) string {
+	zone = strings.TrimSuffix(strings.ToLower(zone), ".")
+	if n, ok := strings.CutSuffix(zone, listSuffix); ok && !strings.Contains(n, ".") {
+		return n
+	}
+	return ""
+}
+
+// Match says what blocking does with a name in one view.
+type Match struct {
+	View   string `json:"view,omitempty"`
+	Result string `json:"result"`          // blocked, allowed or none
+	Entry  string `json:"entry,omitempty"` // the matching entry: the name, or *.parent
+	RuleID int64  `json:"rule_id,omitempty"`
+	List   string `json:"list,omitempty"` // the blocklist, when a list matched
+}
+
+// Actions of rules.
+const (
+	ActionBlock = "block"
+	ActionAllow = "allow"
+)
+
+// cname is the CNAME target of each action: "." answers NXDOMAIN,
+// rpz-passthru. answers as if there were no rule.
+var cname = map[string]string{ActionBlock: ".", ActionAllow: "rpz-passthru."}
+
+// header starts a policy zone file. There is no $ORIGIN: names are
+// relative to the zone, so a list can be renamed without rewriting its
+// file. The short TTLs make a change reach clients' caches quickly.
+func header(title string, serial uint32) string {
+	return fmt.Sprintf("; %s\n; Generated by Jarl. DO NOT EDIT.\n$TTL 60\n@\tSOA\tlocalhost. hostmaster.localhost. %d 3600 600 86400 60\n\tNS\tlocalhost.\n", title, serial)
+}
+
+// Placeholder is the content of a list's zone file before the list has
+// been downloaded: a valid, empty policy zone.
+func Placeholder() string {
+	return header("Blocklist not downloaded yet.", 1)
+}
+
+// Rule is a block or allow rule entered by hand.
+type Rule struct {
+	Name   string // lowercase, without the final dot
+	Action string // ActionBlock or ActionAllow
+	Exact  bool   // only the name itself, not the names below it
+}
+
+// RuleEntries returns the policy zone owners for rules (relative names,
+// "*." for wildcards) and their actions, with the entries that make the
+// most specific rule win added: named won't apply a wildcard below a name
+// that exists in the zone, so every name below a wildcard that exists
+// (because a more specific rule mentions it) gets the wildcard's action
+// for itself and for the names below it, unless a rule says otherwise.
+// Callers make sure no two rules have the same name and scope.
+func RuleEntries(rules []Rule) map[string]string {
+	e := map[string]string{}
+	for _, r := range rules {
+		e[r.Name] = r.Action
+		if !r.Exact {
+			e["*."+r.Name] = r.Action
+		}
+	}
+	// Every name that exists in the zone: owners and their ancestors.
+	nodes := map[string]bool{}
+	for owner := range e {
+		n := strings.TrimPrefix(owner, "*.")
+		for {
+			nodes[n] = true
+			i := strings.IndexByte(n, '.')
+			if i < 0 {
+				break
+			}
+			n = n[i+1:]
+		}
+	}
+	ordered := make([]string, 0, len(nodes))
+	for n := range nodes {
+		ordered = append(ordered, n)
+	}
+	// Shallow names first, so a filled-in wildcard is inherited further
+	// down.
+	sort.Slice(ordered, func(i, j int) bool {
+		di, dj := strings.Count(ordered[i], "."), strings.Count(ordered[j], ".")
+		if di != dj {
+			return di < dj
+		}
+		return ordered[i] < ordered[j]
+	})
+	for _, n := range ordered {
+		inherited := ""
+		for a := n; ; {
+			i := strings.IndexByte(a, '.')
+			if i < 0 {
+				break
+			}
+			a = a[i+1:]
+			if act, ok := e["*."+a]; ok {
+				inherited = act
+				break
+			}
+		}
+		if inherited == "" {
+			continue
+		}
+		if _, ok := e[n]; !ok {
+			e[n] = inherited
+		}
+		if _, ok := e["*."+n]; !ok {
+			e["*."+n] = inherited
+		}
+	}
+	return e
+}
+
+// PausedZoneFile renders a rules zone that lets every name through, for
+// while blocking is paused: the rules zone comes first, and its match
+// stops named from looking at the lists.
+func PausedZoneFile(title string) string {
+	return header(title+" (blocking is paused)", 1) + "*\tCNAME\trpz-passthru.\n"
+}
+
+// RulesZoneFile renders the rules zone of a view.
+func RulesZoneFile(title string, rules []Rule) string {
+	e := RuleEntries(rules)
+	owners := make([]string, 0, len(e))
+	for o := range e {
+		owners = append(owners, o)
+	}
+	sort.Slice(owners, func(i, j int) bool { return ownerLess(owners[i], owners[j]) })
+	var sb strings.Builder
+	sb.WriteString(header(title, 1))
+	for _, o := range owners {
+		fmt.Fprintf(&sb, "%s\tCNAME\t%s\n", o, cname[e[o]])
+	}
+	return sb.String()
+}
+
+// ownerLess sorts names by their labels from the right (example,
+// ads.example, *.ads.example, cdn.ads.example), so related rules are next
+// to each other.
+func ownerLess(a, b string) bool {
+	ka, kb := reverseLabels(a), reverseLabels(b)
+	return ka < kb
+}
+
+func reverseLabels(n string) string {
+	labels := strings.Split(n, ".")
+	for i, j := 0, len(labels)-1; i < j; i, j = i+1, j-1 {
+		labels[i], labels[j] = labels[j], labels[i]
+	}
+	// A wildcard sorts right after the name it belongs to.
+	return strings.ReplaceAll(strings.Join(labels, "\x00"), "*", "\x01")
+}
+
+// MatchRules finds the rule entry named would apply to name (lowercase,
+// without the final dot) in a rules zone with entries e: the name itself,
+// or else the wildcard of its closest existing ancestor. ok is false when
+// no entry applies.
+func MatchRules(e map[string]string, name string) (owner, action string, ok bool) {
+	if act, found := e[name]; found {
+		return name, act, true
+	}
+	nodes := map[string]bool{}
+	for o := range e {
+		n := strings.TrimPrefix(o, "*.")
+		for {
+			nodes[n] = true
+			i := strings.IndexByte(n, '.')
+			if i < 0 {
+				break
+			}
+			n = n[i+1:]
+		}
+	}
+	if nodes[name] {
+		return "", "", false // the name exists without a rule of its own
+	}
+	for a := name; ; {
+		i := strings.IndexByte(a, '.')
+		if i < 0 {
+			return "", "", false
+		}
+		a = a[i+1:]
+		if nodes[a] {
+			if act, found := e["*."+a]; found {
+				return "*." + a, act, true
+			}
+			return "", "", false
+		}
+	}
+}
+
+// Compact drops entries another entry already covers (a name below a
+// name whose subdomains are blocked). That keeps the zone small, and it
+// matters for correctness: no name exists below a wildcard, so every
+// wildcard applies to all names below it.
+func Compact(l *List) {
+	for n := range l.Domains {
+		for a := n; ; {
+			i := strings.IndexByte(a, '.')
+			if i < 0 {
+				break
+			}
+			a = a[i+1:]
+			if l.Domains[a]&Below != 0 {
+				delete(l.Domains, n)
+				break
+			}
+		}
+	}
+}
+
+// FeedZone writes a list's policy zone to w and returns the number of
+// records and a hash of them (the serial isn't part of the hash, so it
+// tells whether the content changed). l must be compacted.
+func FeedZone(w io.Writer, title string, serial uint32, l *List) (records int, hash string, err error) {
+	names := make([]string, 0, len(l.Domains))
+	for n := range l.Domains {
+		names = append(names, n)
+	}
+	sort.Strings(names)
+	bw := bufio.NewWriterSize(w, 256*1024)
+	h := sha256.New()
+	if _, err := bw.WriteString(header(title, serial)); err != nil {
+		return 0, "", err
+	}
+	write := func(owner string) error {
+		line := owner + "\tCNAME\t.\n"
+		h.Write([]byte(line))
+		records++
+		_, err := bw.WriteString(line)
+		return err
+	}
+	for _, n := range names {
+		f := l.Domains[n]
+		if f&Exact != 0 {
+			if err := write(n); err != nil {
+				return 0, "", err
+			}
+		}
+		if f&Below != 0 {
+			if err := write("*." + n); err != nil {
+				return 0, "", err
+			}
+		}
+	}
+	if err := bw.Flush(); err != nil {
+		return 0, "", err
+	}
+	return records, hex.EncodeToString(h.Sum(nil)), nil
+}
+
+// MatchFeed reports which entry of a list's zone file blocks name: the
+// name itself, or a wildcard of one of its ancestors (the closest).
+// Lists are compacted, so no name exists below a wildcard and the
+// closest wildcard ancestor is the one named uses.
+func MatchFeed(path, name string) (owner string, ok bool, err error) {
+	want := map[string]int{name: 0}
+	depth := 1
+	for a := name; ; depth++ {
+		i := strings.IndexByte(a, '.')
+		if i < 0 {
+			break
+		}
+		a = a[i+1:]
+		want["*."+a] = depth
+	}
+	f, err := os.Open(path)
+	if err != nil {
+		return "", false, err
+	}
+	defer f.Close()
+	best := -1
+	sc := bufio.NewScanner(f)
+	for sc.Scan() {
+		line := sc.Text()
+		o, _, found := strings.Cut(line, "\t")
+		if !found {
+			continue
+		}
+		if d, hit := want[o]; hit && (best < 0 || d < best) {
+			best, owner = d, o
+		}
+	}
+	return owner, best >= 0, sc.Err()
+}

internal/config/config.go

@@ -37,6 +37,27 @@ type Config struct {
 	Stats      Stats    `yaml:"stats"`
 	ACME       ACME     `yaml:"acme"`
 	Porkbun    Porkbun  `yaml:"porkbun"`
+	Blocking   Blocking `yaml:"blocking"`
+}
+
+// Blocking configures blocklist downloads (docs/blocking.md). The lists
+// and rules themselves are configuration in the database.
+type Blocking struct {
+	// Refresh is how often each list is checked for changes; a list is
+	// only downloaded again when it changed.
+	Refresh       Duration `yaml:"refresh"`
+	MaxDownloadMB int      `yaml:"max_download_mb"`
+	MaxEntries    int      `yaml:"max_entries"`
+}
+
+func (b *Blocking) check() error {
+	if b.Refresh < Duration(time.Hour) {
+		return fmt.Errorf("refresh must be at least 1h (list hosts ask not to be polled more often)")
+	}
+	if b.MaxDownloadMB < 1 || b.MaxEntries < 1 {
+		return fmt.Errorf("max_download_mb and max_entries must be at least 1")
+	}
+	return nil
 }
 
 // Porkbun lets Jarl manage domains' name servers, glue records and DNSSEC
@@ -301,6 +322,7 @@ func Default() *Config {
 			TopN:              100,
 		},
 		ACME:     ACME{HTTPReq: HTTPReq{RequireHTTPS: true}},
+		Blocking: Blocking{Refresh: Duration(24 * time.Hour), MaxDownloadMB: 64, MaxEntries: 1_000_000},
 		Backup:   Backup{Dir: "/var/backups/jarl", Retention: Duration(30 * 24 * time.Hour), KeepAtLeast: 7, WarnAfter: Duration(2 * 24 * time.Hour)},
 	}
 }
@@ -369,6 +391,9 @@ func (c *Config) check() error {
 	if err := c.Porkbun.check(); err != nil {
 		return fmt.Errorf("porkbun: %w", err)
 	}
+	if err := c.Blocking.check(); err != nil {
+		return fmt.Errorf("blocking: %w", err)
+	}
 	switch c.Log.Format {
 	case "text", "json":
 	default:
@@ -600,4 +625,12 @@ porkbun:
   api_key: ""          # pk1_...
   secret_api_key: ""   # sk1_...
   domains: []          # only these domains (default: any Jarl zone the key reaches)
+
+# Downloading blocklists (docs/blocking.md). The lists and rules are set up
+# in the web UI or with 'jarl blocklist' and 'jarl block'; this only sets
+# how jarld downloads them.
+blocking:
+  refresh: 24h           # check each list for changes this often (at least 1h)
+  max_download_mb: 64    # refuse larger downloads
+  max_entries: 1000000   # refuse lists with more domains
 `

internal/engine/blocking_test.go

@@ -0,0 +1,283 @@
+package engine
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"jarl/internal/blocking"
+	"jarl/internal/model"
+)
+
+func blockRule(name, action string, exact bool, views ...string) Request {
+	in := BlockRuleInput{Name: &name, Action: &action, Exact: &exact}
+	if len(views) > 0 {
+		in.Views = &views
+	}
+	return NewRequest(OpBlockRuleCreate, 0, in)
+}
+
+func blocklist(name, url string, views ...string) Request {
+	in := BlocklistInput{Name: &name, URL: &url}
+	if len(views) > 0 {
+		in.Views = &views
+	}
+	return NewRequest(OpBlocklistCreate, 0, in)
+}
+
+// listServer serves a blocklist with an ETag, and counts the downloads
+// that sent content.
+type listServer struct {
+	body  atomic.Value
+	full  atomic.Int32
+	calls atomic.Int32
+}
+
+func newListServer(t *testing.T, body string) (*listServer, *httptest.Server) {
+	ls := &listServer{}
+	ls.body.Store(body)
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ls.calls.Add(1)
+		b := ls.body.Load().(string)
+		etag := `"` + string(rune('a'+len(b)%26)) + "x" + string(rune('a'+len(b)/26%26)) + `"`
+		if r.Header.Get("If-None-Match") == etag {
+			w.WriteHeader(http.StatusNotModified)
+			return
+		}
+		w.Header().Set("ETag", etag)
+		ls.full.Add(1)
+		w.Write([]byte(b))
+	}))
+	t.Cleanup(srv.Close)
+	return ls, srv
+}
+
+func TestBlockingRender(t *testing.T) {
+	env := newEnv(t)
+	setupZone(env)
+	env.submit(env.admin,
+		NewRequest(OpViewCreate, 0, ViewInput{Name: model.Ptr("internal"), MatchClients: &[]string{"10.0.0.0/8"}, AdoptZones: true}),
+		NewRequest(OpViewCreate, 0, ViewInput{Name: model.Ptr("external")}),
+	)
+	st := env.state()
+	ext := st.ViewByName("external")
+	env.submit(env.admin, NewRequest(OpOptionCreate, 0, OptionInput{Scope: model.Ptr(model.ScopeView), ScopeID: &ext.ID, Name: model.Ptr("recursion"), Value: model.Ptr("no")}))
+
+	_, srv := newListServer(t, "||ads.example^\n")
+	res := env.submit(env.admin,
+		blocklist("ads", srv.URL+"/list.txt"),
+		blockRule("tracker.example", "block", false),
+		blockRule("cdn.tracker.example", "allow", true),
+	)
+	if res.Ops[1].Summary != "block tracker.example (and below)" || res.Ops[2].Summary != "allow cdn.tracker.example" {
+		t.Errorf("summaries: %q, %q", res.Ops[1].Summary, res.Ops[2].Summary)
+	}
+	conf, _ := os.ReadFile(filepath.Join(env.dir, "etc/named.conf"))
+	c := string(conf)
+	// Automatic views: only internal offers recursion.
+	internal := c[strings.Index(c, `view "internal"`):strings.Index(c, `view "external"`)]
+	for _, want := range []string{
+		"response-policy {\n\t\tzone \"rules.jarl.invalid\" min-update-interval 0 log no;\n\t\tzone \"ads.blocklist.jarl.invalid\" min-update-interval 0 log no;\n\t} qname-wait-recurse no break-dnssec yes;",
+		`zone "rules.jarl.invalid" {`,
+		"allow-query { none; };",
+	} {
+		if !strings.Contains(internal, want) {
+			t.Errorf("view internal lacks %q:\n%s", want, internal)
+		}
+	}
+	if strings.Contains(c[strings.Index(c, `view "external"`):], "response-policy") {
+		t.Error("view external, without recursion, got blocking")
+	}
+	rules, err := os.ReadFile(filepath.Join(env.dir, "zones/internal/rules.jarl.invalid.rpz"))
+	if err != nil || !strings.Contains(string(rules), "cdn.tracker.example\tCNAME\trpz-passthru.\n*.cdn.tracker.example\tCNAME\t.\n") {
+		t.Errorf("rules zone: %v\n%s", err, rules)
+	}
+	// The list's file exists as an empty policy zone until downloaded.
+	b := env.state().BlocklistByName("ads")
+	listFile := filepath.Join(env.dir, "cache/blocklists/list-"+strconv.FormatInt(b.ID, 10)+".rpz")
+	if f, err := os.ReadFile(listFile); err != nil || !strings.Contains(string(f), "not downloaded yet") {
+		t.Errorf("placeholder: %v %s", err, f)
+	}
+
+	// A view a list or rule names can't be deleted.
+	res = env.submit(env.admin, NewRequest(OpBlocklistUpdate, b.ID, BlocklistInput{Views: &[]string{"external"}}))
+	if len(res.Problems) != 1 || res.Problems[0].Code != "blocking_no_recursion" {
+		t.Errorf("a list in a view without recursion: %+v", res.Problems)
+	}
+	if e := env.submitErr(env.admin, NewRequest(OpViewDelete, ext.ID, DeleteInput{Cascade: true})); e.Kind != KindConflict || !strings.Contains(e.Message, "blocklist ads") {
+		t.Errorf("deleting a used view: %+v", e)
+	}
+	st = env.state()
+	// A second rule for the same name and view is refused.
+	if e := env.submitErr(env.admin, blockRule("tracker.example", "allow", true)); e.Kind != KindValidation || !strings.Contains(e.Message, "two rules for tracker.example") {
+		t.Errorf("duplicate rule: %+v", e)
+	}
+	// So is a response-policy option where Jarl writes one.
+	in := st.ViewByName("internal")
+	if e := env.submitErr(env.admin, NewRequest(OpOptionCreate, 0, OptionInput{Scope: model.Ptr(model.ScopeView), ScopeID: &in.ID, Name: model.Ptr("response-policy"), Value: model.Ptr(`{ zone "x"; }`)})); e.Kind != KindValidation {
+		t.Errorf("response-policy option: %+v", e)
+	}
+	// Bad input.
+	for _, req := range []Request{blocklist("Bad Name", srv.URL), blocklist("ok", "ftp://x/list"), blockRule("com", "block", false), blockRule("a.example", "deny", false), blockRule("a.example", "block", false, "nope")} {
+		if e := env.submitErr(env.admin, req); e.Kind != KindBadRequest {
+			t.Errorf("%s: %+v", req.Data, e)
+		}
+	}
+}
+
+func TestBlocklistRefresh(t *testing.T) {
+	env := newEnv(t)
+	setupZone(env)
+	ls, srv := newListServer(t, "# test\n||ads.example^\n0.0.0.0 tracker.example\nnot a domain line\n")
+	env.submit(env.admin, blocklist("ads", srv.URL), blockRule("good.ads.example", "allow", false))
+	b := env.state().BlocklistByName("ads")
+	ctx := context.Background()
+
+	env.e.RefreshDue(ctx)
+	s, _ := env.st.BlocklistStatuses(ctx)
+	st := s[b.ID]
+	if st == nil || st.Error != "" || st.Entries != 2 || st.Records != 3 || st.Skipped != 1 || st.UpdatedAt == nil {
+		t.Fatalf("status after the first download: %+v", st)
+	}
+	file := env.e.cfg.Paths.BlocklistFile(b.ID)
+	if f, _ := os.ReadFile(file); !strings.Contains(string(f), "*.ads.example\tCNAME\t.\n") || !strings.Contains(string(f), "tracker.example\tCNAME\t.\n") {
+		t.Errorf("list zone:\n%s", f)
+	}
+	// Not due again: nothing is fetched.
+	env.e.RefreshDue(ctx)
+	if ls.calls.Load() != 1 {
+		t.Errorf("downloads after a second RefreshDue: %d", ls.calls.Load())
+	}
+	// A cleared cache leaves an empty placeholder: downloaded again at once.
+	os.Remove(file)
+	env.e.RefreshDue(ctx)
+	if ls.calls.Load() != 2 {
+		t.Errorf("downloads after the file was lost: %d", ls.calls.Load())
+	}
+	if f, _ := os.ReadFile(file); !strings.Contains(string(f), "*.ads.example\tCNAME\t.\n") {
+		t.Errorf("list zone after the file was lost:\n%s", f)
+	}
+	// Unchanged on the server: 304, no rewrite.
+	firstHash := st.SHA256
+	fullBefore := ls.full.Load()
+	env.e.RefreshBlocklist(ctx, b.ID, false)
+	if ls.full.Load() != fullBefore {
+		t.Errorf("a conditional download fetched the list again")
+	}
+	// Changed: rewritten.
+	ls.body.Store("||ads.example^\n||more.example^\n")
+	st, err := env.e.RefreshBlocklist(ctx, b.ID, false)
+	if err != nil || st.Entries != 2 || st.Records != 4 || st.SHA256 == firstHash {
+		t.Errorf("after a change: %+v, %v", st, err)
+	}
+	// A broken download keeps the previous version and reports why.
+	before, _ := os.ReadFile(file)
+	ls.body.Store("<html><body>Not found</body></html>\n")
+	st, err = env.e.RefreshBlocklist(ctx, b.ID, true)
+	if err == nil || !strings.Contains(st.Error, "no domains found") {
+		t.Errorf("garbage: %+v, %v", st, err)
+	}
+	if after, _ := os.ReadFile(file); string(after) != string(before) {
+		t.Error("a failed update changed the list's file")
+	}
+	// A failed attempt is retried after RetryAfter, not at every check.
+	calls := ls.calls.Load()
+	env.e.RefreshDue(ctx)
+	if ls.calls.Load() != calls {
+		t.Error("a failed list was tried again before RetryAfter")
+	}
+	// Too big.
+	env.e.Limits.MaxBytes = 10
+	ls.body.Store("||ads.example^\n||more.example^\n||third.example^\n")
+	if st, _ = env.e.RefreshBlocklist(ctx, b.ID, true); !strings.Contains(st.Error, "larger than") {
+		t.Errorf("size limit: %+v", st)
+	}
+	env.e.Limits = DefaultBlocklistLimits()
+	env.e.RefreshBlocklist(ctx, b.ID, true)
+
+	// What blocks what.
+	check := func(name string) blocking.Match {
+		m, err := env.e.CheckBlocking(env.state(), name)
+		if err != nil || len(m) != 1 {
+			t.Fatalf("check %s: %+v %v", name, m, err)
+		}
+		return m[0]
+	}
+	if m := check("x.ads.example"); m.Result != "blocked" || m.List != "ads" || m.Entry != "*.ads.example" {
+		t.Errorf("x.ads.example: %+v", m)
+	}
+	if m := check("a.good.ads.example"); m.Result != "allowed" || m.RuleID == 0 || m.Entry != "*.good.ads.example" {
+		t.Errorf("a.good.ads.example: %+v", m)
+	}
+	if m := check("fine.example"); m.Result != "none" {
+		t.Errorf("fine.example: %+v", m)
+	}
+
+	// Deleting the list removes its file and status.
+	env.submit(env.admin, NewRequest(OpBlocklistDelete, b.ID, nil))
+	env.e.RefreshDue(ctx)
+	if _, err := os.Stat(file); !os.IsNotExist(err) {
+		t.Errorf("the deleted list's file is still there: %v", err)
+	}
+	if s, _ := env.st.BlocklistStatuses(ctx); s[b.ID] != nil {
+		t.Error("the deleted list's status is still there")
+	}
+}
+
+func TestBlockingPause(t *testing.T) {
+	env := newEnv(t)
+	setupZone(env)
+	env.submit(env.admin, blocklist("ads", "https://example.org/list"))
+	rulesFile := filepath.Join(env.dir, "zones/_default/rules.jarl.invalid.rpz")
+	if _, err := os.Stat(rulesFile); !os.IsNotExist(err) {
+		t.Fatal("a rules zone without rules or a pause")
+	}
+	until := env.e.Now().Add(10 * time.Minute)
+	res := env.submit(env.admin, NewRequest(OpBlockingPause, 0, BlockingPauseInput{Until: &until}))
+	if !strings.HasPrefix(res.Ops[0].Summary, "pause blocking until ") {
+		t.Errorf("summary = %q", res.Ops[0].Summary)
+	}
+	f, err := os.ReadFile(rulesFile)
+	if err != nil || !strings.HasSuffix(string(f), "NS\tlocalhost.\n*\tCNAME\trpz-passthru.\n") {
+		t.Fatalf("paused rules zone: %v\n%s", err, f)
+	}
+	conf, _ := os.ReadFile(filepath.Join(env.dir, "etc/named.conf"))
+	if !strings.Contains(string(conf), "zone \"rules.jarl.invalid\" min-update-interval 0 log no;\n\t\tzone \"ads.") {
+		t.Errorf("the paused rules zone must come first:\n%s", conf)
+	}
+	// Not yet time: nothing happens.
+	if got := env.e.ResumeBlocking(context.Background()); !got.Equal(until) {
+		t.Errorf("ResumeBlocking before the end = %v", got)
+	}
+	// Time is up: resumed, and the rules zone is gone again.
+	env.submit(env.admin, blockRule("ads.example", "block", false))
+	env.e.Now = func() time.Time { return until.Add(time.Second) }
+	if got := env.e.ResumeBlocking(context.Background()); !got.IsZero() || env.state().Settings.BlockingPausedUntil != nil {
+		t.Fatalf("after the pause: %v, %v", got, env.state().Settings.BlockingPausedUntil)
+	}
+	if f, _ := os.ReadFile(rulesFile); !strings.Contains(string(f), "*.ads.example\tCNAME\t.\n") || strings.Contains(string(f), "passthru") {
+		t.Errorf("rules zone after the pause:\n%s", f)
+	}
+	// Reverting a pause resumes blocking.
+	until = env.e.Now().Add(time.Hour)
+	res = env.submit(env.admin, NewRequest(OpBlockingPause, 0, BlockingPauseInput{Until: &until}))
+	rev, err := env.e.Revert(context.Background(), res.ChangesetID, env.admin)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := env.e.Apply(context.Background(), rev.ID, env.admin, ApplyOptions{}); err != nil || env.state().Settings.BlockingPausedUntil != nil {
+		t.Errorf("revert of a pause: %v, %v", err, env.state().Settings.BlockingPausedUntil)
+	}
+	// At most a day.
+	long := env.e.Now().Add(48 * time.Hour)
+	if e := env.submitErr(env.admin, NewRequest(OpBlockingPause, 0, BlockingPauseInput{Until: &long})); e.Kind != KindBadRequest {
+		t.Errorf("a two-day pause: %+v", e)
+	}
+}

internal/engine/blocklists.go

@@ -0,0 +1,403 @@
+package engine
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"net/http"
+	"os"
+	"path/filepath"
+	"slices"
+	"strconv"
+	"strings"
+	"time"
+
+	"jarl/internal/blocking"
+	"jarl/internal/model"
+	"jarl/internal/render"
+	"jarl/internal/version"
+)
+
+// BlocklistLimits bound blocklist downloads (blocking in jarl.yaml).
+type BlocklistLimits struct {
+	Refresh    time.Duration // how often a list is checked for changes
+	RetryAfter time.Duration // after a failed attempt
+	MaxBytes   int64         // per download
+	MaxEntries int           // domains per list
+	Timeout    time.Duration // per download
+}
+
+// DefaultBlocklistLimits are the limits without configuration.
+func DefaultBlocklistLimits() BlocklistLimits {
+	return BlocklistLimits{Refresh: 24 * time.Hour, RetryAfter: time.Hour, MaxBytes: 64 << 20, MaxEntries: 1_000_000, Timeout: 2 * time.Minute}
+}
+
+// KickBlocklists asks the download loop to look for work now (a list was
+// added or changed).
+func (e *Engine) KickBlocklists() {
+	select {
+	case e.blKick <- struct{}{}:
+	default:
+	}
+}
+
+// BlocklistKicks delivers KickBlocklists' signals to the download loop.
+func (e *Engine) BlocklistKicks() <-chan struct{} { return e.blKick }
+
+// ensureBlocklistFiles creates missing blocklist zone files as empty
+// policy zones, so named can load its configuration before a list has
+// been downloaded. Existing files are never touched.
+func (e *Engine) ensureBlocklistFiles(paths []string) error {
+	var errs []error
+	for _, path := range paths {
+		if _, err := os.Stat(path); err == nil {
+			continue
+		}
+		if err := e.deploy.writeNew(path, []byte(blocking.Placeholder()), 0o640); err != nil && !errors.Is(err, fs.ErrExist) {
+			errs = append(errs, err)
+		}
+	}
+	return errors.Join(errs...)
+}
+
+// RefreshDue downloads the blocklists that are due: never tried, URL
+// changed, file missing or empty (the cache was cleared), last check older
+// than Refresh, or a failed attempt older than RetryAfter. Lists that are
+// disabled or apply to no view are skipped. It also removes the files and
+// status of deleted lists.
+func (e *Engine) RefreshDue(ctx context.Context) {
+	st, err := e.store.LoadState(ctx)
+	if err != nil {
+		e.log.Warn("blocklists: loading the configuration failed", "err", err)
+		return
+	}
+	statuses, err := e.store.BlocklistStatuses(ctx)
+	if err != nil {
+		e.log.Warn("blocklists: loading their status failed", "err", err)
+		return
+	}
+	out := render.Render(st, e.cfg.Paths, e.cfg.Extras)
+	if err := e.ensureBlocklistFiles(out.Blocklists); err != nil {
+		e.log.Warn("blocklists: creating empty zone files failed", "err", err)
+	}
+	e.cleanBlocklists(ctx, st, statuses)
+	now := e.Now()
+	for _, b := range st.SortedBlocklists() {
+		if b.Disabled || len(st.BlockingViews(b.ViewIDs)) == 0 {
+			continue
+		}
+		s := statuses[b.ID]
+		due := s == nil || s.URL != b.URL || s.CheckedAt == nil
+		if !due {
+			wait := e.Limits.Refresh
+			if s.Error != "" {
+				wait = e.Limits.RetryAfter
+			}
+			due = now.Sub(*s.CheckedAt) >= wait || s.Error == "" && isPlaceholder(e.cfg.Paths.BlocklistFile(b.ID))
+		}
+		if !due {
+			continue
+		}
+		if ctx.Err() != nil {
+			return
+		}
+		if _, err := e.RefreshBlocklist(ctx, b.ID, false); err != nil && ctx.Err() == nil {
+			e.log.Warn("blocklist update failed; named keeps using the previous version", "list", b.Name, "err", err)
+		}
+	}
+}
+
+// isPlaceholder reports whether a list's zone file is missing or still the
+// empty policy zone written before its download.
+func isPlaceholder(path string) bool {
+	f, err := os.Open(path)
+	if err != nil {
+		return true
+	}
+	defer f.Close()
+	head := make([]byte, len(blocking.Placeholder()))
+	n, _ := io.ReadFull(f, head)
+	return string(head[:n]) == blocking.Placeholder()
+}
+
+// cleanBlocklists removes the zone files and status of deleted lists.
+func (e *Engine) cleanBlocklists(ctx context.Context, st *model.State, statuses map[int64]*model.BlocklistStatus) {
+	for id := range statuses {
+		if st.Blocklists[id] == nil {
+			e.store.DeleteBlocklistStatus(ctx, id)
+		}
+	}
+	dir := e.cfg.Paths.BlocklistsDir()
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return
+	}
+	for _, ent := range entries {
+		n := ent.Name()
+		idText, ok := strings.CutPrefix(strings.TrimSuffix(n, ".rpz"), "list-")
+		id, err := strconv.ParseInt(idText, 10, 64)
+		if !ok || !strings.HasSuffix(n, ".rpz") || err != nil || st.Blocklists[id] != nil {
+			continue
+		}
+		if err := os.Remove(filepath.Join(dir, n)); err == nil {
+			e.log.Info("removed the zone file of a deleted blocklist", "file", n)
+		}
+	}
+}
+
+// errNotModified means the server said the list hasn't changed.
+var errNotModified = errors.New("not modified")
+
+// RefreshBlocklist downloads a list now and, when its content changed,
+// replaces its zone file and makes named reload it. force downloads even
+// when the server says nothing changed. A failure keeps the previous
+// version. It returns the new status.
+func (e *Engine) RefreshBlocklist(ctx context.Context, id int64, force bool) (*model.BlocklistStatus, error) {
+	e.blMu.Lock()
+	defer e.blMu.Unlock()
+	st, err := e.store.LoadState(ctx)
+	if err != nil {
+		return nil, err
+	}
+	b := st.Blocklists[id]
+	if b == nil {
+		return nil, errf(KindNotFound, "blocklist %d does not exist", id)
+	}
+	statuses, err := e.store.BlocklistStatuses(ctx)
+	if err != nil {
+		return nil, err
+	}
+	prev := statuses[id]
+	if prev == nil {
+		prev = &model.BlocklistStatus{ID: id}
+	}
+	file := e.cfg.Paths.BlocklistFile(id)
+	now := e.Now()
+	next := *prev
+	next.CheckedAt = &now
+	conditional := !force && prev.URL == b.URL && prev.SHA256 != "" && !isPlaceholder(file)
+	err = e.downloadBlocklist(ctx, st, b, &next, conditional, file)
+	next.URL, next.Error = b.URL, ""
+	if err != nil && !errors.Is(err, errNotModified) {
+		next.Error = err.Error()
+	}
+	if serr := e.store.SetBlocklistStatus(ctx, &next); serr != nil && err == nil {
+		err = serr
+	}
+	if errors.Is(err, errNotModified) {
+		err = nil
+	}
+	return &next, err
+}
+
+// downloadBlocklist fetches, parses, checks and installs a list, filling
+// in s. It returns errNotModified when there is nothing to do.
+func (e *Engine) downloadBlocklist(ctx context.Context, st *model.State, b *model.Blocklist, s *model.BlocklistStatus, conditional bool, file string) error {
+	ctx, cancel := context.WithTimeout(ctx, e.Limits.Timeout)
+	defer cancel()
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, b.URL, nil)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("User-Agent", "Jarl/"+version.Short()+" (blocklist download)")
+	if conditional {
+		if s.ETag != "" {
+			req.Header.Set("If-None-Match", s.ETag)
+		}
+		if s.LastModified != "" {
+			req.Header.Set("If-Modified-Since", s.LastModified)
+		}
+	}
+	client := e.HTTP
+	if client == nil {
+		client = http.DefaultClient
+	}
+	resp, err := client.Do(req)
+	if err != nil {
+		return fmt.Errorf("download failed: %w", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode == http.StatusNotModified && conditional {
+		return errNotModified
+	}
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("download failed: the server answered %s", resp.Status)
+	}
+	zone := blocking.ListZone(b.Name)
+	body := &limitedReader{r: resp.Body, left: e.Limits.MaxBytes}
+	l, err := blocking.Parse(body, blocking.Limits{MaxEntries: e.Limits.MaxEntries, MaxNameLen: 253 - len(zone) - 3})
+	if body.over {
+		return fmt.Errorf("the list is larger than %d MB (blocking.max_download_mb in jarl.yaml)", e.Limits.MaxBytes>>20)
+	}
+	if errors.Is(err, blocking.ErrTooManyEntries) {
+		return fmt.Errorf("%v (blocking.max_entries in jarl.yaml)", err)
+	}
+	if err != nil {
+		return fmt.Errorf("download failed: %w", err)
+	}
+	if len(l.Domains) == 0 {
+		return fmt.Errorf("no domains found in %d lines: is this a blocklist in hosts, domains or Adblock format?", l.Lines)
+	}
+	entries, skipped := len(l.Domains), l.Skipped
+	blocking.Compact(l)
+
+	dir := filepath.Dir(file)
+	if err := e.deploy.EnsureDir(dir, e.deploy.dirMode(dir)); err != nil {
+		return err
+	}
+	tmp, err := os.CreateTemp(dir, ".list-*.rpz")
+	if err != nil {
+		return err
+	}
+	tmpName := tmp.Name()
+	defer os.Remove(tmpName) // after a successful rename, there's nothing to remove
+	records, hash, err := blocking.FeedZone(tmp, fmt.Sprintf("Blocklist %s from %s, %s", b.Name, b.URL, e.Now().UTC().Format(time.RFC3339)), uint32(e.Now().Unix()), l)
+	if cerr := tmp.Close(); err == nil {
+		err = cerr
+	}
+	if err != nil {
+		return err
+	}
+	s.ETag, s.LastModified = resp.Header.Get("ETag"), resp.Header.Get("Last-Modified")
+	s.Entries, s.Skipped = entries, skipped
+	if hash == s.SHA256 && s.URL == b.URL && !isPlaceholder(file) {
+		return errNotModified // same content: named keeps what it has
+	}
+	if e.tools != nil && !e.cfg.SkipCheck {
+		res, err := e.tools.CheckZone(ctx, zone, tmpName)
+		if err != nil {
+			return fmt.Errorf("running named-checkzone failed: %w", err)
+		}
+		if !res.OK {
+			msg := "named-checkzone rejected the list's zone"
+			for _, m := range res.Messages {
+				if m.Error {
+					msg += ": " + m.Text
+					break
+				}
+			}
+			return errors.New(msg)
+		}
+	}
+	if err := e.deploy.finish(tmpName, file, 0o640); err != nil {
+		return err
+	}
+	now := e.Now()
+	s.UpdatedAt, s.Records, s.SHA256 = &now, records, hash
+	e.log.Info("blocklist updated", "list", b.Name, "domains", entries, "records", records, "skipped_lines", skipped)
+	return e.reloadBlocklist(ctx, st, b)
+}
+
+// reloadBlocklist makes named load a list's new file in every view that
+// uses it.
+func (e *Engine) reloadBlocklist(ctx context.Context, st *model.State, b *model.Blocklist) error {
+	if e.cfg.NoReload || e.tools == nil {
+		return nil
+	}
+	if adopted, err := e.Adopted(); err != nil || !adopted {
+		return nil // the file is ready for when named loads Jarl's configuration
+	}
+	for _, z := range render.PolicyZones(st, e.cfg.Paths) {
+		if z.ListID != b.ID {
+			continue
+		}
+		if err := e.tools.ReloadZone(ctx, z.Name, z.View); err != nil {
+			return fmt.Errorf("the list was downloaded, but named didn't reload it: %w", err)
+		}
+	}
+	return nil
+}
+
+// limitedReader reads at most left bytes and notes when there was more.
+type limitedReader struct {
+	r    io.Reader
+	left int64
+	over bool
+}
+
+func (l *limitedReader) Read(p []byte) (int, error) {
+	if l.left <= 0 {
+		var one [1]byte
+		if n, _ := l.r.Read(one[:]); n > 0 {
+			l.over = true
+		}
+		return 0, io.EOF
+	}
+	if int64(len(p)) > l.left {
+		p = p[:l.left]
+	}
+	n, err := l.r.Read(p)
+	l.left -= int64(n)
+	return n, err
+}
+
+// CheckBlocking reports, for every view with blocking, whether name is
+// blocked or allowed there, and by which rule or list. It looks names up
+// the way named does: rules first, then the lists in order.
+func (e *Engine) CheckBlocking(st *model.State, name string) ([]blocking.Match, error) {
+	n, err := blocking.NormalizeName(name)
+	if err != nil {
+		return nil, errf(KindBadRequest, "%v", err)
+	}
+	var out []blocking.Match
+	feeds := map[string]string{} // file -> matching entry ("" none)
+	var cur *blocking.Match
+	for _, z := range render.PolicyZones(st, e.cfg.Paths) {
+		if cur == nil || cur.View != z.View {
+			out = append(out, blocking.Match{View: z.View, Result: "none"})
+			cur = &out[len(out)-1]
+		}
+		if cur.Result != "none" {
+			continue // an earlier zone decided
+		}
+		if z.ListID == 0 {
+			owner, act, ok := blocking.MatchRules(blocking.RuleEntries(render.ViewRules(st, z.ViewID)), n)
+			if ok {
+				cur.Entry, cur.RuleID = owner, ruleFor(st, z.ViewID, owner)
+				cur.Result = map[string]string{blocking.ActionBlock: "blocked", blocking.ActionAllow: "allowed"}[act]
+			}
+			continue
+		}
+		entry, seen := feeds[z.File]
+		if !seen {
+			owner, ok, err := blocking.MatchFeed(z.File, n)
+			if err != nil && !errors.Is(err, fs.ErrNotExist) {
+				return nil, err
+			}
+			if ok {
+				entry = owner
+			}
+			feeds[z.File] = entry
+		}
+		if entry != "" {
+			cur.Result, cur.Entry, cur.List = "blocked", entry, st.Blocklists[z.ListID].Name
+		}
+	}
+	return out, nil
+}
+
+// ruleFor finds the rule behind a rules-zone entry: the rule for the
+// entry's name, or (for entries added so the most specific rule wins) the
+// closest rule above it that covers the names below it.
+func ruleFor(st *model.State, viewID int64, owner string) int64 {
+	name := strings.TrimPrefix(owner, "*.")
+	wild := name != owner
+	var best *model.BlockRule
+	for _, r := range st.SortedBlockRules() {
+		if !slices.Contains(st.BlockingViews(r.ViewIDs), viewID) {
+			continue
+		}
+		if r.Name == name && (!wild || !r.Exact) {
+			return r.ID
+		}
+		if !r.Exact && strings.HasSuffix(name, "."+r.Name) && (best == nil || len(r.Name) > len(best.Name)) {
+			best = r
+		}
+	}
+	if best != nil {
+		return best.ID
+	}
+	return 0
+}

internal/engine/blockops.go

@@ -0,0 +1,308 @@
+package engine
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/url"
+	"regexp"
+	"slices"
+	"strings"
+	"time"
+
+	"jarl/internal/auth"
+	"jarl/internal/blocking"
+	"jarl/internal/model"
+)
+
+// ---- blocking: blocklists and rules (docs/blocking.md)
+
+var blocklistNameRe = regexp.MustCompile(`^[a-z0-9]([a-z0-9-]{0,38}[a-z0-9])?$`)
+
+func blockingAction() auth.Action { return auth.Action{Resource: auth.ResBlocking, Write: true} }
+
+// viewIDs resolves the views of a blocklist or rule input: names or IDs,
+// in view order, without duplicates. nil, nil means "not given".
+func viewIDs(st *model.State, names *[]string, ids *[]int64) ([]int64, error) {
+	if names == nil && ids == nil {
+		return nil, nil
+	}
+	want := map[int64]bool{}
+	if names != nil {
+		for _, n := range *names {
+			v := st.ViewByName(strings.TrimSpace(n))
+			if v == nil {
+				return nil, errf(KindBadRequest, "view %q does not exist", n)
+			}
+			want[v.ID] = true
+		}
+	}
+	if ids != nil {
+		for _, id := range *ids {
+			if st.Views[id] == nil {
+				return nil, errf(KindBadRequest, "view %d does not exist", id)
+			}
+			want[id] = true
+		}
+	}
+	out := []int64{}
+	for _, v := range st.OrderedViews() {
+		if want[v.ID] {
+			out = append(out, v.ID)
+		}
+	}
+	return out, nil
+}
+
+// CheckBlocklistURL checks a blocklist URL: http or https, with a host.
+func CheckBlocklistURL(raw string) (string, error) {
+	raw = strings.TrimSpace(raw)
+	u, err := url.Parse(raw)
+	if err != nil || (u.Scheme != "http" && u.Scheme != "https") || u.Host == "" {
+		return "", fmt.Errorf("%q is not an http or https URL", raw)
+	}
+	return raw, nil
+}
+
+func applyBlocklistPut(st *model.State, op model.Op, c *applyCtx) error {
+	if err := c.require(blockingAction()); err != nil {
+		return err
+	}
+	var in BlocklistInput
+	if err := decode(op.Data, &in); err != nil {
+		return err
+	}
+	var b *model.Blocklist
+	if op.Kind == OpBlocklistCreate {
+		if op.ID == 0 || st.Blocklists[op.ID] != nil {
+			return errf(KindConflict, "blocklist ID %d is already in use", op.ID)
+		}
+		if in.Name == nil || in.URL == nil {
+			return errf(KindBadRequest, "a blocklist needs a name and a URL")
+		}
+		b = &model.Blocklist{ID: op.ID, ViewIDs: []int64{}}
+	} else {
+		b = st.Blocklists[op.ID]
+		if b == nil {
+			return errf(KindNotFound, "blocklist %d does not exist", op.ID)
+		}
+		if err := checkVersion(op, b.Version, "blocklist "+b.Name); err != nil {
+			return err
+		}
+	}
+	if in.Name != nil {
+		name := strings.ToLower(strings.TrimSpace(*in.Name))
+		if !blocklistNameRe.MatchString(name) {
+			return errf(KindBadRequest, "blocklist name %q: use 1 to 40 lowercase letters, digits and hyphens, like hagezi-pro", *in.Name)
+		}
+		if other := st.BlocklistByName(name); other != nil && other.ID != b.ID {
+			return errf(KindConflict, "blocklist %s already exists", name)
+		}
+		b.Name = name
+	}
+	if in.URL != nil {
+		u, err := CheckBlocklistURL(*in.URL)
+		if err != nil {
+			return errf(KindBadRequest, "%v", err)
+		}
+		b.URL = u
+	}
+	ids, err := viewIDs(st, in.Views, in.ViewIDs)
+	if err != nil {
+		return err
+	}
+	if ids != nil {
+		b.ViewIDs = ids
+	}
+	if in.Disabled != nil {
+		b.Disabled = *in.Disabled
+	}
+	if in.Comment != nil {
+		b.Comment = *in.Comment
+	}
+	b.Touch(c.user(), c.now)
+	st.Blocklists[b.ID] = b
+	return nil
+}
+
+func applyBlocklistDelete(st *model.State, op model.Op, c *applyCtx) error {
+	if err := c.require(blockingAction()); err != nil {
+		return err
+	}
+	b := st.Blocklists[op.ID]
+	if b == nil {
+		return errf(KindNotFound, "blocklist %d does not exist", op.ID)
+	}
+	if err := checkVersion(op, b.Version, "blocklist "+b.Name); err != nil {
+		return err
+	}
+	delete(st.Blocklists, b.ID)
+	return nil
+}
+
+func applyBlockRulePut(st *model.State, op model.Op, c *applyCtx) error {
+	if err := c.require(blockingAction()); err != nil {
+		return err
+	}
+	var in BlockRuleInput
+	if err := decode(op.Data, &in); err != nil {
+		return err
+	}
+	var r *model.BlockRule
+	if op.Kind == OpBlockRuleCreate {
+		if op.ID == 0 || st.BlockRules[op.ID] != nil {
+			return errf(KindConflict, "rule ID %d is already in use", op.ID)
+		}
+		if in.Name == nil {
+			return errf(KindBadRequest, "a rule needs a domain name")
+		}
+		r = &model.BlockRule{ID: op.ID, Action: model.BlockActionBlock, ViewIDs: []int64{}}
+	} else {
+		r = st.BlockRules[op.ID]
+		if r == nil {
+			return errf(KindNotFound, "rule %d does not exist", op.ID)
+		}
+		if err := checkVersion(op, r.Version, "rule "+r.Name); err != nil {
+			return err
+		}
+	}
+	if in.Name != nil {
+		n, err := blocking.NormalizeName(*in.Name)
+		if err != nil {
+			return errf(KindBadRequest, "%v", err)
+		}
+		r.Name = n
+	}
+	if in.Action != nil {
+		a := strings.ToLower(strings.TrimSpace(*in.Action))
+		if a != model.BlockActionBlock && a != model.BlockActionAllow {
+			return errf(KindBadRequest, "a rule's action is block or allow, not %q", *in.Action)
+		}
+		r.Action = a
+	}
+	if in.Exact != nil {
+		r.Exact = *in.Exact
+	}
+	ids, err := viewIDs(st, in.Views, in.ViewIDs)
+	if err != nil {
+		return err
+	}
+	if ids != nil {
+		r.ViewIDs = ids
+	}
+	if in.Comment != nil {
+		r.Comment = *in.Comment
+	}
+	r.Touch(c.user(), c.now)
+	st.BlockRules[r.ID] = r
+	return nil
+}
+
+func applyBlockRuleDelete(st *model.State, op model.Op, c *applyCtx) error {
+	if err := c.require(blockingAction()); err != nil {
+		return err
+	}
+	r := st.BlockRules[op.ID]
+	if r == nil {
+		return errf(KindNotFound, "rule %d does not exist", op.ID)
+	}
+	if err := checkVersion(op, r.Version, "rule "+r.Name); err != nil {
+		return err
+	}
+	delete(st.BlockRules, r.ID)
+	return nil
+}
+
+// blockingUsers lists the blocklists and rules that name a view.
+func blockingUsers(st *model.State, viewID int64) []string {
+	var out []string
+	for _, b := range st.SortedBlocklists() {
+		if slices.Contains(b.ViewIDs, viewID) {
+			out = append(out, "blocklist "+b.Name)
+		}
+	}
+	for _, r := range st.SortedBlockRules() {
+		if slices.Contains(r.ViewIDs, viewID) {
+			out = append(out, ruleLabel(r))
+		}
+	}
+	return out
+}
+
+// ruleLabel describes a rule: "block ads.example (and below)".
+func ruleLabel(r *model.BlockRule) string {
+	s := r.Action + " " + r.Name
+	if !r.Exact {
+		s += " (and below)"
+	}
+	return s
+}
+
+// ---- expansion
+
+func (x *expander) blocklistCreate(req Request) ([]model.Op, error) {
+	return x.simpleCreate(req, OpBlocklistCreate, func(data json.RawMessage) (string, error) {
+		var in BlocklistInput
+		if err := decode(data, &in); err != nil {
+			return "", err
+		}
+		if in.Name == nil || in.URL == nil {
+			return "", errf(KindBadRequest, "a blocklist needs a name and a URL")
+		}
+		return "add blocklist " + *in.Name + " (" + *in.URL + ")", nil
+	})
+}
+
+func (x *expander) blockRuleCreate(req Request) ([]model.Op, error) {
+	return x.simpleCreate(req, OpBlockRuleCreate, func(data json.RawMessage) (string, error) {
+		var in BlockRuleInput
+		if err := decode(data, &in); err != nil {
+			return "", err
+		}
+		if in.Name == nil {
+			return "", errf(KindBadRequest, "a rule needs a domain name")
+		}
+		r := &model.BlockRule{Name: strings.ToLower(strings.TrimSuffix(strings.TrimSpace(*in.Name), ".")), Action: model.BlockActionBlock}
+		if in.Action != nil {
+			r.Action = strings.ToLower(*in.Action)
+		}
+		if in.Exact != nil {
+			r.Exact = *in.Exact
+		}
+		return ruleLabel(r), nil
+	})
+}
+
+func applyBlockingPause(st *model.State, op model.Op, c *applyCtx) error {
+	if err := c.require(blockingAction()); err != nil {
+		return err
+	}
+	var in BlockingPauseInput
+	if err := decode(op.Data, &in); err != nil {
+		return err
+	}
+	if in.Until != nil && in.Until.Sub(c.now) > MaxBlockingPause+time.Minute {
+		return errf(KindBadRequest, "blocking can be paused for at most %s; disable lists to stop using them", MaxBlockingPause)
+	}
+	st.Settings.BlockingPausedUntil = in.Until
+	return nil
+}
+
+// ResumeBlocking ends a pause whose time is up, and returns when the
+// current pause ends (zero when blocking isn't paused).
+func (e *Engine) ResumeBlocking(ctx context.Context) time.Time {
+	st, err := e.store.LoadState(ctx)
+	if err != nil || st.Settings.BlockingPausedUntil == nil {
+		return time.Time{}
+	}
+	until := *st.Settings.BlockingPausedUntil
+	if e.Now().Before(until) {
+		return until
+	}
+	if _, err := e.Submit(ctx, []Request{NewRequest(OpBlockingPause, 0, BlockingPauseInput{})}, auth.System, "system", "resume blocking after the pause", ApplyOptions{}); err != nil {
+		e.log.Warn("resuming blocking after the pause failed; it will be tried again", "err", err)
+		return e.Now().Add(time.Minute)
+	}
+	e.log.Info("blocking resumed after the pause")
+	return time.Time{}
+}

internal/engine/deploy.go

@@ -183,6 +183,48 @@ func (d *Deployer) writeAtomic(path string, content []byte, mode fs.FileMode) er
 	return nil
 }
 
+// writeNew creates a file that doesn't exist yet (fs.ErrExist if it
+// does), with the deploy group.
+func (d *Deployer) writeNew(path string, content []byte, mode fs.FileMode) error {
+	dir := filepath.Dir(path)
+	if err := d.EnsureDir(dir, d.dirMode(dir)); err != nil {
+		return err
+	}
+	f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_EXCL, mode)
+	if err != nil {
+		return err
+	}
+	_, err = f.Write(content)
+	if gid, gerr := d.groupID(); err == nil && gerr == nil && gid >= 0 {
+		err = f.Chown(-1, gid)
+	}
+	if cerr := f.Close(); err == nil {
+		err = cerr
+	}
+	if err != nil {
+		os.Remove(path)
+	}
+	return err
+}
+
+// finish gives a temporary file written next to path its mode and the
+// deploy group, and moves it into place.
+func (d *Deployer) finish(tmp, path string, mode fs.FileMode) error {
+	if err := os.Chmod(tmp, mode); err != nil {
+		return err
+	}
+	gid, err := d.groupID()
+	if err != nil {
+		return err
+	}
+	if gid >= 0 {
+		if err := os.Chown(tmp, -1, gid); err != nil {
+			return fmt.Errorf("chgrp %s: %w", path, err)
+		}
+	}
+	return os.Rename(tmp, path)
+}
+
 // Install writes files and removes paths, returning a backup that undoes
 // the changes. On error the files already written are restored.
 func (d *Deployer) Install(files []*render.File, remove []string, dirs []string) (*Backup, error) {

internal/engine/diffops.go

@@ -17,6 +17,9 @@ func DiffOps(from, to *model.State) []model.Op {
 	add := func(kind string, id int64, base int, data any, summary string) {
 		ops = append(ops, newOp(kind, id, base, data, summary))
 	}
+	if !reflect.DeepEqual(from.Settings.BlockingPausedUntil, to.Settings.BlockingPausedUntil) {
+		add(OpBlockingPause, 0, 0, BlockingPauseInput{Until: to.Settings.BlockingPausedUntil}, map[bool]string{true: "pause blocking", false: "resume blocking"}[to.Settings.BlockingPausedUntil != nil])
+	}
 	if !reflect.DeepEqual(stripVersion(from.Settings), stripVersion(to.Settings)) {
 		s := to.Settings
 		add(OpSettingsUpdate, 0, 0, SettingsInput{DefaultTTL: &s.DefaultTTL, Nameservers: model.Ptr(append([]string{}, s.Nameservers...)), RName: &s.RName,
@@ -101,7 +104,35 @@ func DiffOps(from, to *model.State) []model.Op {
 			add(OpRecordUpdate, k, o.Version, in, fmt.Sprintf("restore %s %s %s", n.Name, n.Type, n.Data))
 		}
 	}
+	for _, k := range sortedKeys(to.Blocklists) {
+		n := to.Blocklists[k]
+		in := BlocklistInput{Name: &n.Name, URL: &n.URL, ViewIDs: model.Ptr(append([]int64{}, n.ViewIDs...)), Disabled: &n.Disabled, Comment: &n.Comment}
+		if o, ok := from.Blocklists[k]; !ok {
+			add(OpBlocklistCreate, k, 0, in, "add blocklist "+n.Name)
+		} else if !sameObject(o, n) {
+			add(OpBlocklistUpdate, k, o.Version, in, "restore blocklist "+n.Name)
+		}
+	}
+	for _, k := range sortedKeys(to.BlockRules) {
+		n := to.BlockRules[k]
+		in := BlockRuleInput{Name: &n.Name, Action: &n.Action, Exact: &n.Exact, ViewIDs: model.Ptr(append([]int64{}, n.ViewIDs...)), Comment: &n.Comment}
+		if o, ok := from.BlockRules[k]; !ok {
+			add(OpBlockRuleCreate, k, 0, in, "add rule: "+ruleLabel(n))
+		} else if !sameObject(o, n) {
+			add(OpBlockRuleUpdate, k, o.Version, in, "restore rule: "+ruleLabel(n))
+		}
+	}
 	// Deletions, most dependent objects first.
+	for _, k := range sortedKeys(from.BlockRules) {
+		if _, ok := to.BlockRules[k]; !ok {
+			add(OpBlockRuleDelete, k, from.BlockRules[k].Version, nil, "delete rule: "+ruleLabel(from.BlockRules[k]))
+		}
+	}
+	for _, k := range sortedKeys(from.Blocklists) {
+		if _, ok := to.Blocklists[k]; !ok {
+			add(OpBlocklistDelete, k, from.Blocklists[k].Version, nil, "delete blocklist "+from.Blocklists[k].Name)
+		}
+	}
 	for _, k := range sortedKeys(from.Records) {
 		if _, ok := to.Records[k]; !ok {
 			o := from.Records[k]
@@ -156,6 +187,7 @@ func DiffOps(from, to *model.State) []model.Op {
 
 func stripVersion(s model.Settings) model.Settings {
 	s.Version = 0
+	s.BlockingPausedUntil = nil // its own operation
 	return s
 }
 

internal/engine/engine.go

@@ -14,8 +14,10 @@ import (
 	"fmt"
 	"io/fs"
 	"log/slog"
+	"net/http"
 	"os"
 	"path/filepath"
+	"slices"
 	"sort"
 	"strings"
 	"sync"
@@ -23,6 +25,7 @@ import (
 
 	"jarl/internal/auth"
 	"jarl/internal/bind"
+	"jarl/internal/blocking"
 	"jarl/internal/dnsname"
 	"jarl/internal/model"
 	"jarl/internal/namedconf"
@@ -64,6 +67,12 @@ type Engine struct {
 	deploy *Deployer
 	mu     sync.Mutex // serializes applies
 	Now    func() time.Time
+
+	// Blocklist downloads (blocklists.go).
+	blMu   sync.Mutex    // serializes downloads
+	blKick chan struct{} // a list was added or changed
+	HTTP   *http.Client  // for downloads; nil: a default client
+	Limits BlocklistLimits
 }
 
 // New creates an engine.
@@ -78,6 +87,8 @@ func New(st *store.Store, tools *bind.Tools, cfg Config, log *slog.Logger) *Engi
 		store: st, tools: tools, cfg: cfg, log: log,
 		deploy: &Deployer{Group: cfg.FileGroup, NamedWritable: []string{cfg.Paths.ZoneDir, cfg.Paths.CacheDir}},
 		Now:    time.Now,
+		blKick: make(chan struct{}, 1),
+		Limits: DefaultBlocklistLimits(),
 	}
 }
 
@@ -383,6 +394,7 @@ type plan struct {
 	drift         []DriftEntry
 	configChanged bool
 	reloadZones   []*model.Zone
+	reloadPolicy  []render.PolicyZone // rules zones whose file changed
 	verify        map[int64]uint32
 	newZones      bool
 	backup        *Backup
@@ -446,7 +458,7 @@ func (e *Engine) makePlan(ctx context.Context, base, work *model.State, user str
 		}
 	}
 	for path, df := range deployed {
-		if pl.out.File(path) != nil || df.Kind != render.KindZone {
+		if pl.out.File(path) != nil || df.Kind != render.KindZone && df.Kind != render.KindPolicy {
 			continue
 		}
 		old, existed, _ := readFile(path)
@@ -484,6 +496,16 @@ func (e *Engine) makePlan(ctx context.Context, base, work *model.State, user str
 	if len(work.Zones) != len(base.Zones) {
 		pl.configChanged = true
 	}
+	// Rules zones whose content changed. New ones come with a change to
+	// named.conf, and reconfig loads them.
+	for _, z := range pl.out.Policy {
+		if z.ListID != 0 || !changedPaths[z.File] {
+			continue
+		}
+		if slices.Contains(baseOut.Policy, z) {
+			pl.reloadPolicy = append(pl.reloadPolicy, z)
+		}
+	}
 
 	if !e.cfg.SkipCheck {
 		if err := e.stagingCheck(ctx, pl); err != nil {
@@ -519,6 +541,16 @@ func (e *Engine) stagingCheck(ctx context.Context, pl *plan) error {
 			return err
 		}
 	}
+	// Blocklists as empty policy zones: their content is checked when
+	// they are downloaded.
+	for _, path := range sout.Blocklists {
+		if err := os.MkdirAll(filepath.Dir(path), 0o750); err != nil {
+			return err
+		}
+		if err := os.WriteFile(path, []byte(blocking.Placeholder()), 0o640); err != nil {
+			return err
+		}
+	}
 	main, err := e.stagingMain(dir, sp.MainConfig())
 	if err != nil {
 		return err
@@ -796,6 +828,12 @@ func (e *Engine) applyOps(ctx context.Context, cs *model.Changeset, reqs []Reque
 	res.ChangesetID = cs.ID
 	res.Applied = true
 	e.removeDerived(pl)
+	for _, op := range cs.Ops {
+		if strings.HasPrefix(op.Kind, "blocklist.") || op.Kind == OpBlockingPause {
+			e.KickBlocklists()
+			break
+		}
+	}
 	e.log.Info("changeset applied", "changeset", cs.ID, "user", p.Name(), "ops", len(cs.Ops), "files", len(res.Files), "description", cs.Description)
 	return res, nil
 }
@@ -829,6 +867,9 @@ func (e *Engine) deployAndReload(ctx context.Context, pl *plan, res *Result, rel
 		return &Error{Kind: KindBIND, Message: "writing configuration files failed (nothing was changed): " + err.Error()}
 	}
 	pl.backup = backup
+	if err := e.ensureBlocklistFiles(pl.out.Blocklists); err != nil {
+		e.log.Warn("creating a blocklist's empty zone file failed", "err", err)
+	}
 	pl.reloaded = reload
 	if !reload {
 		return nil
@@ -860,6 +901,11 @@ func (e *Engine) rollback(ctx context.Context, pl *plan) {
 			e.log.Error("rndc reload after restore failed", "zone", z.Name, "err", err)
 		}
 	}
+	for _, z := range pl.reloadPolicy {
+		if err := e.tools.ReloadZone(ctx, z.Name, z.View); err != nil {
+			e.log.Error("rndc reload after restore failed", "zone", z.Name, "err", err)
+		}
+	}
 }
 
 // namedView returns the view name to pass to rndc for a zone ("" without
@@ -885,6 +931,16 @@ func (e *Engine) reload(ctx context.Context, pl *plan) ([]string, error) {
 		}
 		done = append(done, "reload "+zoneDesc(pl.work, z))
 	}
+	for _, z := range pl.reloadPolicy {
+		label := "blocking rules"
+		if z.View != "" {
+			label += " [view " + z.View + "]"
+		}
+		if err := e.tools.ReloadZone(ctx, z.Name, z.View); err != nil {
+			return done, fmt.Errorf("reloading %s failed: %v", label, err)
+		}
+		done = append(done, "reload "+label)
+	}
 	// named reloads zones asynchronously and reports load errors only in
 	// its log, so wait until it serves the new serials.
 	deadline := time.Now().Add(e.cfg.ReloadTimeout)
@@ -1003,6 +1059,12 @@ func (e *Engine) Resync(ctx context.Context, p *auth.Principal, opts ApplyOption
 			pl.verify[z.ID] = z.SOA.Serial
 		}
 	}
+	pl.reloadPolicy = nil
+	for _, z := range pl.out.Policy {
+		if z.ListID == 0 {
+			pl.reloadPolicy = append(pl.reloadPolicy, z)
+		}
+	}
 	reload := !e.cfg.NoReload && !opts.NoReload
 	if adopted, aerr := e.Adopted(); reload && (aerr != nil || !adopted) {
 		reload = false

internal/engine/expand.go

@@ -222,6 +222,40 @@ func (x *expander) expand(req Request) ([]model.Op, error) {
 		return []model.Op{x.versioned(req, o.Version, summary)}, nil
 	case OpSettingsUpdate:
 		return []model.Op{newOpRaw(OpSettingsUpdate, 0, 0, req.Data, "update settings")}, nil
+	case OpBlocklistCreate:
+		return x.blocklistCreate(req)
+	case OpBlocklistUpdate, OpBlocklistDelete:
+		b := x.st.Blocklists[req.ID]
+		if b == nil {
+			return nil, errf(KindNotFound, "blocklist %d does not exist", req.ID)
+		}
+		verb := "change"
+		if req.Op == OpBlocklistDelete {
+			verb = "delete"
+		}
+		return []model.Op{x.versioned(req, b.Version, verb+" blocklist "+b.Name)}, nil
+	case OpBlockingPause:
+		var in BlockingPauseInput
+		if err := decode(req.Data, &in); err != nil {
+			return nil, err
+		}
+		summary := "resume blocking"
+		if in.Until != nil {
+			summary = "pause blocking until " + in.Until.Local().Format("2006-01-02 15:04")
+		}
+		return []model.Op{newOpRaw(OpBlockingPause, 0, 0, req.Data, summary)}, nil
+	case OpBlockRuleCreate:
+		return x.blockRuleCreate(req)
+	case OpBlockRuleUpdate, OpBlockRuleDelete:
+		r := x.st.BlockRules[req.ID]
+		if r == nil {
+			return nil, errf(KindNotFound, "rule %d does not exist", req.ID)
+		}
+		verb := "change rule: "
+		if req.Op == OpBlockRuleDelete {
+			verb = "delete rule: "
+		}
+		return []model.Op{x.versioned(req, r.Version, verb+ruleLabel(r))}, nil
 	}
 	return nil, errf(KindBadRequest, "unknown operation %q", req.Op)
 }

internal/engine/inputs.go

@@ -2,6 +2,7 @@ package engine
 
 import (
 	"encoding/json"
+	"time"
 
 	"jarl/internal/model"
 )
@@ -30,6 +31,14 @@ const (
 	OpOptionDelete   = "option.delete"
 	OpSettingsUpdate = "settings.update"
 
+	OpBlocklistCreate = "blocklist.create"
+	OpBlocklistUpdate = "blocklist.update"
+	OpBlocklistDelete = "blocklist.delete"
+	OpBlockRuleCreate = "blockrule.create"
+	OpBlockRuleUpdate = "blockrule.update"
+	OpBlockRuleDelete = "blockrule.delete"
+	OpBlockingPause   = "blocking.pause"
+
 	// Requests only: disabling and enabling records, by ID or by match
 	// (zone, name, type and optionally data), become record.update
 	// operations.
@@ -40,7 +49,8 @@ const (
 // OpKinds lists all operation kinds.
 var OpKinds = []string{OpZoneCreate, OpZoneUpdate, OpZoneDelete, OpRecordCreate, OpRecordUpdate, OpRecordDelete, OpRRSetReplace,
 	OpViewCreate, OpViewUpdate, OpViewDelete, OpViewReorder, OpACLCreate, OpACLUpdate, OpACLDelete,
-	OpTSIGCreate, OpTSIGUpdate, OpTSIGDelete, OpOptionCreate, OpOptionUpdate, OpOptionDelete, OpSettingsUpdate}
+	OpTSIGCreate, OpTSIGUpdate, OpTSIGDelete, OpOptionCreate, OpOptionUpdate, OpOptionDelete, OpSettingsUpdate,
+	OpBlocklistCreate, OpBlocklistUpdate, OpBlocklistDelete, OpBlockRuleCreate, OpBlockRuleUpdate, OpBlockRuleDelete, OpBlockingPause}
 
 // Request is an operation as submitted by a client. Requests are expanded
 // into one or more stored operations (for example an A record with "ptr"
@@ -213,3 +223,35 @@ type SettingsInput struct {
 type DeleteInput struct {
 	Cascade bool `json:"cascade,omitempty"`
 }
+
+// BlocklistInput creates or updates a blocklist. Views are given by name
+// (Views) or ID (ViewIDs); an empty list means every view that offers
+// recursion.
+type BlocklistInput struct {
+	Name     *string   `json:"name,omitempty"`
+	URL      *string   `json:"url,omitempty"`
+	Views    *[]string `json:"views,omitempty"`
+	ViewIDs  *[]int64  `json:"view_ids,omitempty"`
+	Disabled *bool     `json:"disabled,omitempty"`
+	Comment  *string   `json:"comment,omitempty"`
+}
+
+// BlockRuleInput creates or updates a block or allow rule. Views as for
+// BlocklistInput.
+type BlockRuleInput struct {
+	Name    *string   `json:"name,omitempty"`
+	Action  *string   `json:"action,omitempty"` // block (default) or allow
+	Exact   *bool     `json:"exact,omitempty"`  // only the name, not the names below it
+	Views   *[]string `json:"views,omitempty"`
+	ViewIDs *[]int64  `json:"view_ids,omitempty"`
+	Comment *string   `json:"comment,omitempty"`
+}
+
+// BlockingPauseInput pauses blocking until a time, or resumes it (null).
+type BlockingPauseInput struct {
+	Until *time.Time `json:"until"`
+}
+
+// MaxBlockingPause is the longest pause: blocking shouldn't stay off by
+// mistake (disable lists to stop using them).
+const MaxBlockingPause = 24 * time.Hour

internal/engine/ops.go

@@ -98,6 +98,16 @@ func applyOp(st *model.State, op model.Op, c *applyCtx) error {
 		err = applyOptionDelete(st, op, c)
 	case OpSettingsUpdate:
 		err = applySettings(st, op, c)
+	case OpBlocklistCreate, OpBlocklistUpdate:
+		err = applyBlocklistPut(st, op, c)
+	case OpBlocklistDelete:
+		err = applyBlocklistDelete(st, op, c)
+	case OpBlockRuleCreate, OpBlockRuleUpdate:
+		err = applyBlockRulePut(st, op, c)
+	case OpBlockRuleDelete:
+		err = applyBlockRuleDelete(st, op, c)
+	case OpBlockingPause:
+		err = applyBlockingPause(st, op, c)
 	default:
 		err = errf(KindBadRequest, "unknown operation %q", op.Kind)
 	}
@@ -831,6 +841,9 @@ func applyViewDelete(st *model.State, op model.Op, c *applyCtx) error {
 	if err := decode(op.Data, &in); err != nil {
 		return err
 	}
+	if users := blockingUsers(st, v.ID); len(users) > 0 {
+		return errf(KindConflict, "view %s is used by %s; change them to other views first", v.Name, strings.Join(users, ", "))
+	}
 	zones := st.ZonesInView(v.ID)
 	if len(zones) > 0 && !in.Cascade {
 		var names []string

internal/model/blocking.go

@@ -0,0 +1,136 @@
+package model
+
+import (
+	"slices"
+	"sort"
+	"strings"
+	"time"
+)
+
+// Blocklist is a list of domains to block, downloaded from URL and kept up
+// to date by jarld (docs/blocking.md).
+type Blocklist struct {
+	ID   int64  `json:"id"`
+	Name string `json:"name"` // a DNS label: it names the list's policy zone
+	URL  string `json:"url"`
+	// ViewIDs are the views the list applies to; empty means every view
+	// that offers recursion (see BlockingViews).
+	ViewIDs  []int64 `json:"view_ids"`
+	Disabled bool    `json:"disabled,omitempty"`
+	Comment  string  `json:"comment"`
+	Meta
+}
+
+// Block rule actions.
+const (
+	BlockActionBlock = "block"
+	BlockActionAllow = "allow"
+)
+
+// BlockRule blocks or allows a domain, and unless Exact the names below
+// it. Rules take precedence over blocklists.
+type BlockRule struct {
+	ID      int64   `json:"id"`
+	Name    string  `json:"name"`   // lowercase, without the final dot
+	Action  string  `json:"action"` // block or allow
+	Exact   bool    `json:"exact,omitempty"`
+	ViewIDs []int64 `json:"view_ids"` // as for Blocklist
+	Comment string  `json:"comment"`
+	Meta
+}
+
+// BlocklistStatus is what jarld knows about a list's downloads. It is not
+// configuration: it is kept outside changesets.
+type BlocklistStatus struct {
+	ID           int64      `json:"id"`
+	URL          string     `json:"url"` // the URL last tried
+	ETag         string     `json:"-"`
+	LastModified string     `json:"-"`
+	CheckedAt    *time.Time `json:"checked_at,omitempty"` // last attempt
+	UpdatedAt    *time.Time `json:"updated_at,omitempty"` // last time the content changed
+	Entries      int        `json:"entries"`              // domains
+	Records      int        `json:"records"`              // policy zone records
+	Skipped      int        `json:"skipped"`              // lines that weren't usable
+	SHA256       string     `json:"-"`
+	Error        string     `json:"error,omitempty"` // the last attempt failed
+}
+
+// BlocklistByName finds a blocklist by name.
+func (s *State) BlocklistByName(name string) *Blocklist {
+	for _, b := range s.Blocklists {
+		if strings.EqualFold(b.Name, name) {
+			return b
+		}
+	}
+	return nil
+}
+
+// SortedBlocklists returns the blocklists ordered by name.
+func (s *State) SortedBlocklists() []*Blocklist {
+	out := make([]*Blocklist, 0, len(s.Blocklists))
+	for _, b := range s.Blocklists {
+		out = append(out, b)
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].Name < out[j].Name })
+	return out
+}
+
+// SortedBlockRules returns the rules ordered by domain, parents first.
+func (s *State) SortedBlockRules() []*BlockRule {
+	out := make([]*BlockRule, 0, len(s.BlockRules))
+	for _, r := range s.BlockRules {
+		out = append(out, r)
+	}
+	sort.Slice(out, func(i, j int) bool {
+		a, b := out[i], out[j]
+		if a.Name != b.Name {
+			return CanonicalLess(a.Name+".", b.Name+".")
+		}
+		if a.Exact != b.Exact {
+			return !a.Exact
+		}
+		return a.ID < b.ID
+	})
+	return out
+}
+
+// RecursionOn reports whether a view (0: the server without views) offers
+// recursion: its recursion option, else the server's, else BIND's default
+// (yes).
+func (s *State) RecursionOn(viewID int64) bool {
+	o := s.FindOption(ScopeView, viewID, "recursion")
+	if viewID == 0 || o == nil {
+		if g := s.FindOption(ScopeOptions, 0, "recursion"); o == nil {
+			o = g
+		}
+	}
+	if o == nil {
+		return true
+	}
+	switch strings.ToLower(strings.Trim(strings.TrimSpace(o.Value), `";`)) {
+	case "no", "false", "0":
+		return false
+	}
+	return true
+}
+
+// BlockingViews returns the views a blocklist or rule with viewIDs applies
+// to, in view order: the given views, or when none are given every view
+// that offers recursion (blocking only affects recursive queries). Without
+// views it returns []int64{0}, the whole server, if it offers recursion.
+func (s *State) BlockingViews(viewIDs []int64) []int64 {
+	views := s.OrderedViews()
+	if len(views) == 0 {
+		if !s.RecursionOn(0) {
+			return nil
+		}
+		return []int64{0}
+	}
+	var out []int64
+	for _, v := range views {
+		if len(viewIDs) == 0 && s.RecursionOn(v.ID) || slices.Contains(viewIDs, v.ID) {
+			out = append(out, v.ID)
+		}
+	}
+	return out
+}

internal/model/model.go

@@ -208,6 +208,9 @@ type Settings struct {
 	Expire       uint32   `json:"expire"`
 	NegativeTTL  uint32   `json:"negative_ttl"`
 	SerialPolicy string   `json:"serial_policy"`
+	// BlockingPausedUntil, while set, lets every name through blocking
+	// (docs/blocking.md); jarld clears it when the time is up.
+	BlockingPausedUntil *time.Time `json:"blocking_paused_until,omitempty"`
 	Version             int        `json:"version"`
 }
 
@@ -232,6 +235,9 @@ type State struct {
 	Zones    map[int64]*Zone
 	Records  map[int64]*Record
 	Options  map[int64]*Option
+	// Blocking (docs/blocking.md).
+	Blocklists map[int64]*Blocklist
+	BlockRules map[int64]*BlockRule
 }
 
 // NewState returns an empty state with default settings.
@@ -244,6 +250,9 @@ func NewState() *State {
 		Zones:    map[int64]*Zone{},
 		Records:  map[int64]*Record{},
 		Options:  map[int64]*Option{},
+
+		Blocklists: map[int64]*Blocklist{},
+		BlockRules: map[int64]*BlockRule{},
 	}
 }
 
@@ -257,6 +266,9 @@ func (s *State) Clone() *State {
 		Zones:    make(map[int64]*Zone, len(s.Zones)),
 		Records:  make(map[int64]*Record, len(s.Records)),
 		Options:  make(map[int64]*Option, len(s.Options)),
+
+		Blocklists: make(map[int64]*Blocklist, len(s.Blocklists)),
+		BlockRules: make(map[int64]*BlockRule, len(s.BlockRules)),
 	}
 	c.Settings.Nameservers = append([]string(nil), s.Settings.Nameservers...)
 	for id, v := range s.Views {
@@ -294,6 +306,16 @@ func (s *State) Clone() *State {
 		n := *o
 		c.Options[id] = &n
 	}
+	for id, b := range s.Blocklists {
+		n := *b
+		n.ViewIDs = append([]int64(nil), b.ViewIDs...)
+		c.Blocklists[id] = &n
+	}
+	for id, r := range s.BlockRules {
+		n := *r
+		n.ViewIDs = append([]int64(nil), r.ViewIDs...)
+		c.BlockRules[id] = &n
+	}
 	return c
 }
 

internal/namedconf/printer.go

@@ -36,6 +36,24 @@ func Compact(items []Item) string {
 // CompactStmt returns the statement on a single line with its semicolon.
 func CompactStmt(s *Stmt) string { return Compact(s.Items) + ";" }
 
+// FormatValue returns an option's value laid out as named.conf writes it:
+// blocks over several lines, indented with tabs. Values without a block,
+// and values that don't parse, are returned as they are.
+func FormatValue(name, value string) string {
+	if !strings.Contains(value, "{") {
+		return value
+	}
+	st, err := ParseOptionValue(name, value)
+	if err != nil {
+		return value
+	}
+	out := strings.TrimSuffix(strings.TrimRight(FormatStmt(st, 0), "\n"), ";")
+	if rest, ok := strings.CutPrefix(out, st.Keyword()); ok {
+		return strings.TrimLeft(rest, " ")
+	}
+	return value
+}
+
 // QuoteString returns s as a named.conf quoted string.
 func QuoteString(s string) string {
 	var sb strings.Builder

internal/namedconf/printer_test.go

@@ -0,0 +1,18 @@
+package namedconf
+
+import "testing"
+
+func TestFormatValue(t *testing.T) {
+	for _, c := range []struct{ name, value, want string }{
+		{"logging", `{ channel c { file "/var/log/named/x.log" versions 3; print-time yes; }; category default { c; }; }`,
+			// A short inner block stays on one line, as in named.conf.
+			"{\n\tchannel c { file \"/var/log/named/x.log\" versions 3; print-time yes; };\n\tcategory default { c; };\n}"},
+		{"allow-query", `{ allowed_clients; }`, `{ allowed_clients; }`}, // short: unchanged
+		{"directory", `"/var/cache/bind"`, `"/var/cache/bind"`},
+		{"logging", `{ broken`, `{ broken`}, // unparsable: as it is
+	} {
+		if got := FormatValue(c.name, c.value); got != c.want {
+			t.Errorf("FormatValue(%s, %q) =\n%s\nwant\n%s", c.name, c.value, got, c.want)
+		}
+	}
+}

internal/render/blocking.go

@@ -0,0 +1,167 @@
+package render
+
+import (
+	"fmt"
+	"path/filepath"
+	"slices"
+	"strings"
+
+	"jarl/internal/blocking"
+	"jarl/internal/model"
+	"jarl/internal/namedconf"
+)
+
+// KindPolicy is the kind of a rendered rules policy zone file.
+const KindPolicy = "policy"
+
+// PolicyZone is a response policy zone in named's configuration
+// (docs/blocking.md).
+type PolicyZone struct {
+	Name   string // without the final dot
+	ViewID int64  // 0 without views
+	View   string // "" without views
+	File   string
+	ListID int64 // the blocklist; 0 for the rules zone
+}
+
+// BlocklistsDir holds the zone files of downloaded blocklists, one per
+// list, shared by the views that use it.
+func (p Paths) BlocklistsDir() string { return filepath.Join(p.CacheDir, "blocklists") }
+
+// BlocklistFile returns the zone file of a blocklist. It is named after
+// the list's ID, so renaming the list doesn't move it.
+func (p Paths) BlocklistFile(id int64) string {
+	return filepath.Join(p.BlocklistsDir(), fmt.Sprintf("list-%d.rpz", id))
+}
+
+// rulesFile returns a view's rules zone file.
+func (p Paths) rulesFile(view string) string {
+	return filepath.Join(p.ZoneDir, ViewDir(view), blocking.RulesZone+".rpz")
+}
+
+// PolicyZones returns the policy zones named loads, per view in view
+// order, each view's in the order named checks them: the rules zone first
+// (rules win over lists), then the enabled lists by name.
+func PolicyZones(s *model.State, p Paths) []PolicyZone {
+	var out []PolicyZone
+	rules, lists := s.SortedBlockRules(), s.SortedBlocklists()
+	scopes := []int64{0}
+	if len(s.Views) > 0 {
+		scopes = nil
+		for _, v := range s.OrderedViews() {
+			scopes = append(scopes, v.ID)
+		}
+	}
+	for _, vid := range scopes {
+		view := ""
+		if v := s.Views[vid]; v != nil {
+			view = v.Name
+		}
+		var zones []PolicyZone
+		hasRules := false
+		for _, r := range rules {
+			if slices.Contains(s.BlockingViews(r.ViewIDs), vid) {
+				hasRules = true
+				break
+			}
+		}
+		for _, b := range lists {
+			if !b.Disabled && slices.Contains(s.BlockingViews(b.ViewIDs), vid) {
+				zones = append(zones, PolicyZone{Name: blocking.ListZone(b.Name), ViewID: vid, View: view, File: p.BlocklistFile(b.ID), ListID: b.ID})
+			}
+		}
+		// While paused, every view with blocking gets a rules zone: it
+		// lets everything through.
+		if hasRules || s.Settings.BlockingPausedUntil != nil && len(zones) > 0 {
+			out = append(out, PolicyZone{Name: blocking.RulesZone, ViewID: vid, View: view, File: p.rulesFile(view)})
+		}
+		out = append(out, zones...)
+	}
+	return out
+}
+
+// ViewRules returns the rules that apply in a view (0 without views).
+func ViewRules(s *model.State, viewID int64) []blocking.Rule {
+	var out []blocking.Rule
+	for _, r := range s.SortedBlockRules() {
+		if slices.Contains(s.BlockingViews(r.ViewIDs), viewID) {
+			out = append(out, blocking.Rule{Name: r.Name, Action: r.Action, Exact: r.Exact})
+		}
+	}
+	return out
+}
+
+// writeResponsePolicy writes the response-policy statement for a view's
+// policy zones (or the server's, without views). Rewrites are logged to
+// Jarl's response log when statistics read it, and not at all otherwise
+// (they would go to named's default log).
+func writeResponsePolicy(w *confWriter, zones []PolicyZone, logRewrites bool) {
+	if len(zones) == 0 {
+		return
+	}
+	w.begin("blocking", 0, "blocking (rules and blocklists)")
+	w.write("\t// Blocking (docs/blocking.md): rules first, then blocklists.\n\tresponse-policy {\n")
+	for _, z := range zones {
+		// Apply a new version at once: Jarl reloads a list only when it
+		// changed (at most every blocking.refresh), so named's default
+		// delay for batching frequent updates only adds a wait.
+		opts := []string{"min-update-interval 0"}
+		if !logRewrites {
+			opts = append(opts, "log no")
+		}
+		w.write(fmt.Sprintf("\t\tzone %s%s;\n", namedconf.QuoteString(z.Name), prefixSpace(strings.Join(opts, " "))))
+	}
+	// Block without waiting for the real answer, and also for clients
+	// that ask for DNSSEC data.
+	w.write("\t} qname-wait-recurse no break-dnssec yes;\n")
+	w.end()
+}
+
+func prefixSpace(s string) string {
+	if s == "" {
+		return ""
+	}
+	return " " + s
+}
+
+// writePolicyZones writes the zone statements of policy zones and adds
+// their files to the output: rules zone files are rendered, blocklist
+// files only listed (jarld downloads them; see Output.Blocklists).
+func writePolicyZones(w *confWriter, s *model.State, zones []PolicyZone, out *Output, indent int) {
+	tabs := strings.Repeat("\t", indent)
+	for _, z := range zones {
+		w.write("\n")
+		label := "blocking: your rules"
+		if z.ListID != 0 {
+			label = "blocking: blocklist " + s.Blocklists[z.ListID].Name
+		}
+		w.begin("blocking", z.ListID, label)
+		w.write(fmt.Sprintf("%szone %s {\n%s\ttype primary;\n%s\tfile %s;\n%s\tallow-query { none; };\n%s\tallow-transfer { none; };\n%s\tnotify no;\n%s};\n",
+			tabs, namedconf.QuoteString(z.Name), tabs, tabs, namedconf.QuoteString(z.File), tabs, tabs, tabs, tabs))
+		w.end()
+		if z.ListID != 0 {
+			out.Blocklists = appendUnique(out.Blocklists, z.File)
+			continue
+		}
+		title := "Blocking rules"
+		if z.View != "" {
+			title += " for view " + z.View
+		}
+		content := blocking.RulesZoneFile(title, ViewRules(s, z.ViewID))
+		if s.Settings.BlockingPausedUntil != nil {
+			content = blocking.PausedZoneFile(title)
+		}
+		out.Files = append(out.Files, &File{Path: z.File, Content: []byte(content), Mode: 0o640, Kind: KindPolicy})
+	}
+}
+
+// scopeZones returns the policy zones of one view (0 without views).
+func scopeZones(all []PolicyZone, viewID int64) []PolicyZone {
+	var out []PolicyZone
+	for _, z := range all {
+		if z.ViewID == viewID {
+			out = append(out, z)
+		}
+	}
+	return out
+}

internal/render/render.go

@@ -69,6 +69,11 @@ type Output struct {
 	Spans map[string][]Span
 	// ZoneFiles maps zone IDs to the file named loads for the zone.
 	ZoneFiles map[int64]string
+	// Policy lists the response policy zones (docs/blocking.md).
+	Policy []PolicyZone
+	// Blocklists are the zone files of blocklists named loads. jarld
+	// downloads them; until then they must exist, as empty policy zones.
+	Blocklists []string
 }
 
 // File returns the rendered file at path, or nil.
@@ -264,6 +269,9 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 
 	st := x.Stats
 	logResponses := st != nil && st.LogFile != ""
+	pzs := PolicyZones(s, p)
+	out.Policy = pzs
+	logRewrites := logResponses && len(pzs) > 0
 	sawStats, sawLogging := false, false
 	if top := s.ScopedOptions(model.ScopeTopLevel, 0); len(top) > 0 {
 		w.write("\n")
@@ -274,7 +282,7 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 				w.write(st.statsStatement(o))
 				sawStats = true
 			case logResponses && o.Name == "logging" && !sawLogging:
-				w.write(st.loggingStatement(o))
+				w.write(st.loggingStatement(o, logRewrites))
 				sawLogging = true
 			default:
 				w.write(optionText(o, 0))
@@ -289,7 +297,7 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 			w.write(st.statsStatement(nil))
 		}
 		if logResponses && !sawLogging {
-			w.write(st.loggingStatement(nil))
+			w.write(st.loggingStatement(nil, logRewrites))
 		}
 		w.end()
 	}
@@ -322,10 +330,14 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 		w.write("\t// " + statsComment + "\n\tresponselog yes;\n")
 		w.end()
 	}
-	w.write("};\n")
-
 	views := s.OrderedViews()
 	if len(views) == 0 {
+		writeResponsePolicy(w, scopeZones(pzs, 0), logResponses)
+	}
+	w.write("};\n")
+
+	if len(views) == 0 {
+		writePolicyZones(w, s, scopeZones(pzs, 0), out, 0)
 		for _, z := range s.ZonesInView(0) {
 			w.write("\n")
 			renderZone(w, s, z, p, out, 0)
@@ -352,6 +364,8 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 			w.write(optionText(o, 1))
 			w.end()
 		}
+		writeResponsePolicy(w, scopeZones(pzs, v.ID), logResponses)
+		writePolicyZones(w, s, scopeZones(pzs, v.ID), out, 1)
 		for _, z := range s.ZonesInView(v.ID) {
 			w.write("\n")
 			renderZone(w, s, z, p, out, 1)

internal/render/stats.go

@@ -69,8 +69,9 @@ func (h *StatsHooks) statsStatement(user *model.Option) string {
 }
 
 // loggingStatement returns the logging statement with Jarl's channel and
-// the responses category, merged into the user's own if there is one.
-func (h *StatsHooks) loggingStatement(user *model.Option) string {
+// the responses category (and rpz, for blocking's rewrites), merged into
+// the user's own if there is one.
+func (h *StatsHooks) loggingStatement(user *model.Option, rpz bool) string {
 	var st *namedconf.Stmt
 	if user != nil {
 		var err error
@@ -84,15 +85,21 @@ func (h *StatsHooks) loggingStatement(user *model.Option) string {
 	b := st.FirstBlock()
 	// Channels must be defined before the categories that use them.
 	b.Stmts = append([]*namedconf.Stmt{h.logChannel()}, b.Stmts...)
+	categories := []string{"responses"}
+	if rpz {
+		categories = append(categories, "rpz")
+	}
+	for _, cat := range categories {
 		merged := false
 		for _, s := range b.Stmts {
-		if s.Keyword() == "category" && strings.EqualFold(s.Arg(0), "responses") && s.FirstBlock() != nil {
+			if s.Keyword() == "category" && strings.EqualFold(s.Arg(0), cat) && s.FirstBlock() != nil {
 				s.FirstBlock().Stmts = append(s.FirstBlock().Stmts, namedconf.NewStmt(StatsChannelName))
 				merged = true
 			}
 		}
 		if !merged {
-		b.Stmts = append(b.Stmts, namedconf.NewStmt("category", "responses", namedconf.NewBlock(namedconf.NewStmt(StatsChannelName))))
+			b.Stmts = append(b.Stmts, namedconf.NewStmt("category", cat, namedconf.NewBlock(namedconf.NewStmt(StatsChannelName))))
+		}
 	}
 	prefix := ""
 	if user != nil {

internal/server/blocking_test.go

@@ -0,0 +1,111 @@
+package server
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestBlockingAPI(t *testing.T) {
+	e := newAPIEnv(t)
+	lists := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/missing" {
+			http.NotFound(w, r)
+			return
+		}
+		w.Write([]byte("||ads.example^\n0.0.0.0 tracker.example\n"))
+	}))
+	defer lists.Close()
+
+	b := e.do("POST", "/blocking/lists", e.token, map[string]any{"name": "ads", "url": lists.URL + "/list.txt"}, 201)["object"].(map[string]any)
+	if b["name"] != "ads" || b["state"] != "waiting" {
+		t.Errorf("new list = %v", b)
+	}
+	got := e.do("POST", "/blocking/lists/ads/refresh", e.token, nil, 200)
+	st, _ := got["status"].(map[string]any)
+	if got["state"] != "ok" || st["entries"] != 2.0 || st["records"] != 3.0 {
+		t.Errorf("after refresh = %v", got)
+	}
+	e.do("POST", "/blocking/rules", e.token, map[string]any{"name": "Good.Ads.Example.", "action": "allow"}, 201)
+	r := e.do("POST", "/blocking/rules", e.token, map[string]any{"name": "more.example", "exact": true}, 201)["object"].(map[string]any)
+	if r["name"] != "more.example" || r["action"] != "block" || r["exact"] != true {
+		t.Errorf("new rule = %v", r)
+	}
+	for name, want := range map[string]string{"x.ads.example": "blocked", "a.good.ads.example": "allowed", "more.example": "blocked", "sub.more.example": "none"} {
+		m := e.list("/blocking/check?name="+name, e.token)
+		if len(m) != 1 || m[0]["result"] != want {
+			t.Errorf("check %s = %v, want %s", name, m, want)
+		}
+	}
+	if _, status := e.req("GET", "/blocking/check?name=com", e.token, nil); status != 400 {
+		t.Errorf("check of a TLD = %d", status)
+	}
+
+	// Staged changes show as pending.
+	cs := itoa(int64(e.do("POST", "/changesets", e.token, map[string]any{"description": "more"}, 201)["id"].(float64)))
+	e.do("POST", "/blocking/rules?changeset="+cs, e.token, map[string]any{"name": "staged.example"}, 202)
+	e.do("PATCH", "/blocking/lists/ads?changeset="+cs, e.token, map[string]any{"disabled": true}, 202)
+	pending := map[string]any{}
+	for _, x := range e.list("/blocking/rules?changeset="+cs, e.token) {
+		pending[x["name"].(string)] = x["pending"]
+	}
+	if pending["staged.example"] != "add" || pending["more.example"] != nil {
+		t.Errorf("pending rules = %v", pending)
+	}
+	if l := e.list("/blocking/lists?changeset="+cs, e.token); len(l) != 1 || l[0]["pending"] != "change" || l[0]["state"] != "disabled" {
+		t.Errorf("pending list = %v", l)
+	}
+	e.do("POST", "/changesets/"+cs+"/discard", e.token, nil, 204)
+
+	// Delete rules by name; a missing one is a 404 unless missing_ok.
+	e.do("DELETE", "/blocking/rules?name=more.example", e.token, nil, 200)
+	if _, status := e.req("DELETE", "/blocking/rules?name=more.example", e.token, nil); status != 404 {
+		t.Errorf("deleting a missing rule = %d", status)
+	}
+	e.do("DELETE", "/blocking/rules?name=more.example&missing_ok=1", e.token, nil, 200)
+
+	// Readers see blocking but can't change it.
+	e.do("POST", "/users", e.token, map[string]any{"username": "reader", "password": "reader-password-123", "grant_strings": []string{"blocking:read"}}, 201)
+	var readerID int64
+	for _, u := range e.list("/users", e.token) {
+		if u["username"] == "reader" {
+			readerID = int64(u["id"].(float64))
+		}
+	}
+	rt := e.do("POST", "/users/"+itoa(readerID)+"/tokens", e.token, map[string]any{"name": "t"}, 201)["token"].(string)
+	if l := e.list("/blocking/lists", rt); len(l) != 1 {
+		t.Errorf("reader's lists = %v", l)
+	}
+	for _, c := range []struct{ method, path string }{{"POST", "/blocking/rules"}, {"POST", "/blocking/lists/ads/refresh"}, {"DELETE", "/blocking/lists/ads"}} {
+		if _, status := e.req(c.method, c.path, rt, map[string]any{"name": "x.example"}); status != 403 {
+			t.Errorf("reader %s %s = %d", c.method, c.path, status)
+		}
+	}
+	// Pausing.
+	if _, status := e.req("POST", "/blocking/pause", e.token, map[string]any{"minutes": 0}); status != 400 {
+		t.Errorf("a 0-minute pause = %d", status)
+	}
+	e.do("POST", "/blocking/pause", e.token, map[string]any{"minutes": 30}, 201)
+	if st := e.do("GET", "/blocking/status", e.token, nil, 200); st["paused_until"] == nil {
+		t.Errorf("status while paused = %v", st)
+	}
+	if st := e.do("GET", "/status", e.token, nil, 200); st["blocking_paused_until"] == nil {
+		t.Errorf("dashboard while paused = %v", st["blocking_paused_until"])
+	}
+	e.do("POST", "/blocking/resume", e.token, nil, 201)
+	if st := e.do("GET", "/blocking/status", e.token, nil, 200); st["paused_until"] != nil {
+		t.Errorf("status after resuming = %v", st)
+	}
+
+	// A list that can't be downloaded shows on the dashboard.
+	e.do("POST", "/blocking/lists", e.token, map[string]any{"name": "gone", "url": lists.URL + "/missing"}, 201)
+	if l := e.do("POST", "/blocking/lists/gone/refresh", e.token, nil, 200); l["state"] != "error" {
+		t.Errorf("failed list = %v", l)
+	}
+	errs, _ := e.do("GET", "/status", e.token, nil, 200)["blocklist_errors"].([]any)
+	if len(errs) != 1 || errs[0].(map[string]any)["name"] != "gone" {
+		t.Errorf("status blocklist_errors = %v", errs)
+	}
+	e.do("DELETE", "/blocking/lists/gone", e.token, nil, 200)
+	e.do("DELETE", "/blocking/lists/ads", e.token, nil, 200)
+}

internal/server/clientnames_test.go

@@ -0,0 +1,38 @@
+package server
+
+import (
+	"net/netip"
+	"testing"
+
+	"jarl/internal/model"
+)
+
+func TestClientNames(t *testing.T) {
+	st := model.NewState()
+	add := func(id int64, name, typ, data string, disabled bool) {
+		st.Records[id] = &model.Record{ID: id, ZoneID: 1, Name: name, Type: typ, Data: data, Disabled: disabled}
+	}
+	add(1, "nas.adbraun.lol.", "A", "192.168.1.20", false)
+	add(2, "20.1.168.192.in-addr.arpa.", "PTR", "storage.adbraun.lol.", false) // PTR wins over A
+	add(3, "web.adbraun.lol.", "A", "192.168.1.30", false)                     // no PTR: the A record's name
+	add(4, "alias.adbraun.lol.", "A", "192.168.1.30", false)                   // first in name order wins
+	add(5, "old.adbraun.lol.", "A", "192.168.1.40", true)                      // disabled: ignored
+	add(6, "secret.adbraun.lol.", "A", "192.168.1.50", false)                  // not readable
+	add(7, "v6.adbraun.lol.", "AAAA", "2001:db8::7", false)
+	add(8, "printer.adbraun.lol.", "A", "192.168.1.60", false) // not asked for
+
+	want := map[netip.Addr]bool{}
+	for _, a := range []string{"192.168.1.20", "192.168.1.30", "192.168.1.40", "192.168.1.50", "2001:db8::7", "10.0.0.1"} {
+		want[netip.MustParseAddr(a)] = true
+	}
+	got := clientNames(st, want, func(r *model.Record) bool { return r.ID != 6 })
+	exp := map[string]string{"192.168.1.20": "storage.adbraun.lol", "192.168.1.30": "alias.adbraun.lol", "2001:db8::7": "v6.adbraun.lol"}
+	if len(got) != len(exp) {
+		t.Errorf("got %v", got)
+	}
+	for a, n := range exp {
+		if got[netip.MustParseAddr(a)] != n {
+			t.Errorf("%s = %q, want %q", a, got[netip.MustParseAddr(a)], n)
+		}
+	}
+}

internal/server/h_blocking.go

@@ -0,0 +1,403 @@
+package server
+
+import (
+	"context"
+	"net/http"
+	"slices"
+	"strconv"
+	"strings"
+	"time"
+
+	"jarl/internal/api"
+	"jarl/internal/auth"
+	"jarl/internal/blocking"
+	"jarl/internal/engine"
+	"jarl/internal/model"
+)
+
+// ---- blocking (docs/blocking.md)
+
+// bytesPerRecord is what named 9.20 needs per policy zone record and view,
+// measured with lists of a few hundred thousand entries.
+const bytesPerRecord = 630
+
+func viewNames(st *model.State, ids []int64) []string {
+	out := []string{}
+	for _, id := range ids {
+		if v := st.Views[id]; v != nil {
+			out = append(out, v.Name)
+		}
+	}
+	return out
+}
+
+func presentBlocklist(st *model.State, b *model.Blocklist, status *model.BlocklistStatus) api.Blocklist {
+	views := st.BlockingViews(b.ViewIDs)
+	out := api.Blocklist{Blocklist: *b, Views: viewNames(st, views), AutoViews: len(b.ViewIDs) == 0 && len(st.Views) > 0, Status: status}
+	switch {
+	case b.Disabled:
+		out.State = "disabled"
+	case len(views) == 0:
+		out.State = "idle"
+	case status != nil && status.Error != "":
+		out.State = "error"
+	case status == nil || status.UpdatedAt == nil:
+		out.State = "waiting"
+	default:
+		out.State = "ok"
+	}
+	if status != nil && !b.Disabled {
+		out.MemoryMB = int((int64(status.Records)*bytesPerRecord*int64(len(views)) + 1<<19) >> 20)
+	}
+	return out
+}
+
+func presentBlockRule(st *model.State, r *model.BlockRule) api.BlockRule {
+	return api.BlockRule{BlockRule: *r, Views: viewNames(st, st.BlockingViews(r.ViewIDs)), AutoViews: len(r.ViewIDs) == 0 && len(st.Views) > 0}
+}
+
+func requireBlocking(p *auth.Principal) error {
+	return require(p, auth.Action{Resource: auth.ResBlocking})
+}
+
+func (s *Server) listBlocklists(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := requireBlocking(p); err != nil {
+		return err
+	}
+	st, base, err := s.states(r)
+	if err != nil {
+		return err
+	}
+	statuses, err := s.store.BlocklistStatuses(r.Context())
+	if err != nil {
+		return err
+	}
+	out := []api.Blocklist{}
+	for _, b := range st.SortedBlocklists() {
+		o := presentBlocklist(st, b, statuses[b.ID])
+		o.Pending = pending(base, base != nil && base.Blocklists[b.ID] == nil, base != nil && base.Blocklists[b.ID] != nil && base.Blocklists[b.ID].Version != b.Version)
+		out = append(out, o)
+	}
+	if base != nil {
+		for _, b := range base.SortedBlocklists() {
+			if st.Blocklists[b.ID] == nil {
+				o := presentBlocklist(base, b, statuses[b.ID])
+				o.Pending = "delete"
+				out = append(out, o)
+			}
+		}
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
+// pending returns the pending marker of an object listed with a changeset.
+func pending(base *model.State, added, changed bool) string {
+	switch {
+	case base == nil:
+		return ""
+	case added:
+		return "add"
+	case changed:
+		return "change"
+	}
+	return ""
+}
+
+func (s *Server) blocklistByPath(r *http.Request, st *model.State) (*model.Blocklist, error) {
+	ref := r.PathValue("id")
+	var b *model.Blocklist
+	if id, err := strconv.ParseInt(ref, 10, 64); err == nil {
+		b = st.Blocklists[id]
+	} else {
+		b = st.BlocklistByName(ref)
+	}
+	if b == nil {
+		return nil, notFound("blocklist %s not found", ref)
+	}
+	return b, nil
+}
+
+func (s *Server) blocklistObject(ctx context.Context) func(*model.State, int64) any {
+	return func(st *model.State, id int64) any {
+		b := st.Blocklists[id]
+		if b == nil {
+			return nil
+		}
+		statuses, _ := s.store.BlocklistStatuses(ctx)
+		return presentBlocklist(st, b, statuses[id])
+	}
+}
+
+func (s *Server) getBlocklist(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := requireBlocking(p); err != nil {
+		return err
+	}
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	b, err := s.blocklistByPath(r, st)
+	if err != nil {
+		return err
+	}
+	writeJSON(w, http.StatusOK, s.blocklistObject(r.Context())(st, b.ID))
+	return nil
+}
+
+func (s *Server) createBlocklist(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	body, err := readBody(r)
+	if err != nil {
+		return err
+	}
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlocklistCreate, 0, body)}, s.blocklistObject(r.Context()))
+}
+
+func (s *Server) updateBlocklist(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	b, err := s.blocklistByPath(r, st)
+	if err != nil {
+		return err
+	}
+	body, err := readBody(r)
+	if err != nil {
+		return err
+	}
+	id := b.ID
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlocklistUpdate, id, body)}, func(st *model.State, _ int64) any { return s.blocklistObject(r.Context())(st, id) })
+}
+
+func (s *Server) deleteBlocklist(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	b, err := s.blocklistByPath(r, st)
+	if err != nil {
+		return err
+	}
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlocklistDelete, b.ID, nil)}, nil)
+}
+
+// refreshBlocklist: POST /blocking/lists/{id}/refresh[?force=1] downloads
+// the list now and waits for the result.
+func (s *Server) refreshBlocklist(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := require(p, auth.Action{Resource: auth.ResBlocking, Write: true}); err != nil {
+		return err
+	}
+	st, err := s.store.LoadState(r.Context())
+	if err != nil {
+		return err
+	}
+	b, err := s.blocklistByPath(r, st)
+	if err != nil {
+		return err
+	}
+	ctx, cancel := context.WithTimeout(r.Context(), 3*time.Minute)
+	defer cancel()
+	status, rerr := s.eng.RefreshBlocklist(ctx, b.ID, queryBool(r, "force"))
+	if status == nil {
+		return rerr
+	}
+	writeJSON(w, http.StatusOK, presentBlocklist(st, b, status))
+	return nil
+}
+
+func (s *Server) listBlockRules(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := requireBlocking(p); err != nil {
+		return err
+	}
+	st, base, err := s.states(r)
+	if err != nil {
+		return err
+	}
+	out := []api.BlockRule{}
+	for _, rule := range st.SortedBlockRules() {
+		o := presentBlockRule(st, rule)
+		o.Pending = pending(base, base != nil && base.BlockRules[rule.ID] == nil, base != nil && base.BlockRules[rule.ID] != nil && base.BlockRules[rule.ID].Version != rule.Version)
+		out = append(out, o)
+	}
+	if base != nil {
+		for _, rule := range base.SortedBlockRules() {
+			if st.BlockRules[rule.ID] == nil {
+				o := presentBlockRule(base, rule)
+				o.Pending = "delete"
+				out = append(out, o)
+			}
+		}
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
+func ruleObject(st *model.State, id int64) any {
+	if rule := st.BlockRules[id]; rule != nil {
+		return presentBlockRule(st, rule)
+	}
+	return nil
+}
+
+func (s *Server) ruleByPath(r *http.Request, st *model.State) (*model.BlockRule, error) {
+	id, _ := strconv.ParseInt(r.PathValue("id"), 10, 64)
+	rule := st.BlockRules[id]
+	if rule == nil {
+		return nil, notFound("rule %s not found", r.PathValue("id"))
+	}
+	return rule, nil
+}
+
+func (s *Server) createBlockRule(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	body, err := readBody(r)
+	if err != nil {
+		return err
+	}
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlockRuleCreate, 0, body)}, ruleObject)
+}
+
+func (s *Server) updateBlockRule(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	rule, err := s.ruleByPath(r, st)
+	if err != nil {
+		return err
+	}
+	body, err := readBody(r)
+	if err != nil {
+		return err
+	}
+	id := rule.ID
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlockRuleUpdate, id, body)}, func(st *model.State, _ int64) any { return ruleObject(st, id) })
+}
+
+func (s *Server) deleteBlockRule(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	rule, err := s.ruleByPath(r, st)
+	if err != nil {
+		return err
+	}
+	return s.mutate(w, r, p, "", []engine.Request{request(engine.OpBlockRuleDelete, rule.ID, nil)}, nil)
+}
+
+// deleteBlockRulesByName: DELETE /blocking/rules?name=NAME[&view=VIEW]
+// deletes the rules for a domain (in one view, or all).
+func (s *Server) deleteBlockRulesByName(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	q := r.URL.Query()
+	name := strings.TrimSuffix(strings.ToLower(strings.TrimSpace(q.Get("name"))), ".")
+	if name == "" {
+		return badRequest("give the domain of the rules to delete (name=)")
+	}
+	var viewID int64 = -1
+	if vn := q.Get("view"); vn != "" {
+		v := st.ViewByName(vn)
+		if v == nil {
+			return notFound("view %s not found", vn)
+		}
+		viewID = v.ID
+	}
+	var reqs []engine.Request
+	for _, rule := range st.SortedBlockRules() {
+		if rule.Name != name {
+			continue
+		}
+		if viewID >= 0 && !slices.Contains(st.BlockingViews(rule.ViewIDs), viewID) {
+			continue
+		}
+		reqs = append(reqs, request(engine.OpBlockRuleDelete, rule.ID, nil))
+	}
+	if len(reqs) == 0 {
+		if queryBool(r, "missing_ok") {
+			writeJSON(w, http.StatusOK, api.MutationResponse{})
+			return nil
+		}
+		return notFound("there is no rule for %s", name)
+	}
+	return s.mutate(w, r, p, "", reqs, nil)
+}
+
+// checkBlocking: GET /blocking/check?name=NAME says what blocking does
+// with a name in each view.
+func (s *Server) checkBlocking(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := requireBlocking(p); err != nil {
+		return err
+	}
+	st, err := s.store.LoadState(r.Context())
+	if err != nil {
+		return err
+	}
+	out, err := s.eng.CheckBlocking(st, r.URL.Query().Get("name"))
+	if err != nil {
+		return err
+	}
+	if out == nil {
+		out = []blocking.Match{}
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
+// blocklistErrors lists the enabled blocklists whose last update failed,
+// for the dashboard.
+func (s *Server) blocklistErrors(ctx context.Context) []api.BlocklistError {
+	st, err := s.store.LoadState(ctx)
+	if err != nil || len(st.Blocklists) == 0 {
+		return nil
+	}
+	statuses, err := s.store.BlocklistStatuses(ctx)
+	if err != nil {
+		return nil
+	}
+	var out []api.BlocklistError
+	for _, b := range st.SortedBlocklists() {
+		if s := statuses[b.ID]; s != nil && s.Error != "" && !b.Disabled {
+			out = append(out, api.BlocklistError{Name: b.Name, Error: s.Error, UpdatedAt: s.UpdatedAt})
+		}
+	}
+	return out
+}
+
+// blockingStatus: GET /blocking/status says whether blocking is paused.
+func (s *Server) blockingStatus(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	if err := requireBlocking(p); err != nil {
+		return err
+	}
+	st, err := s.store.LoadState(r.Context())
+	if err != nil {
+		return err
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"paused_until": st.Settings.BlockingPausedUntil})
+	return nil
+}
+
+// pauseBlocking: POST /blocking/pause {"minutes": 10} lets every name
+// through until then; POST /blocking/resume ends it.
+func (s *Server) pauseBlocking(resume bool) func(http.ResponseWriter, *http.Request, *auth.Principal) error {
+	return func(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+		var in engine.BlockingPauseInput
+		if !resume {
+			var body struct {
+				Minutes int `json:"minutes"`
+			}
+			if err := decodeJSON(r, &body); err != nil {
+				return err
+			}
+			if body.Minutes < 1 || time.Duration(body.Minutes)*time.Minute > engine.MaxBlockingPause {
+				return badRequest("pause for 1 to %d minutes", int(engine.MaxBlockingPause/time.Minute))
+			}
+			until := time.Now().Add(time.Duration(body.Minutes) * time.Minute).Truncate(time.Second)
+			in.Until = &until
+		}
+		return s.mutate(w, r, p, "", []engine.Request{engine.NewRequest(engine.OpBlockingPause, 0, in)}, nil)
+	}
+}

internal/server/h_changes.go

@@ -279,6 +279,12 @@ func (s *Server) status(w http.ResponseWriter, r *http.Request, p *auth.Principa
 		resp.Backup = s.backupStatus(r.Context(), now)
 		resp.TOTP = s.totpOverview(r.Context())
 	}
+	if p.Can(auth.Action{Resource: auth.ResBlocking}) {
+		resp.BlocklistErrors = s.blocklistErrors(r.Context())
+		if st, err := s.store.LoadState(r.Context()); err == nil {
+			resp.BlockingPausedUntil = st.Settings.BlockingPausedUntil
+		}
+	}
 	writeJSON(w, http.StatusOK, resp)
 	return nil
 }

internal/server/h_stats.go

@@ -2,10 +2,14 @@ package server
 
 import (
 	"net/http"
+	"net/netip"
+	"slices"
 	"strings"
 	"time"
 
 	"jarl/internal/auth"
+	"jarl/internal/dnsname"
+	"jarl/internal/model"
 	"jarl/internal/stats"
 )
 
@@ -53,6 +57,9 @@ func (s *Server) statsSummary(w http.ResponseWriter, r *http.Request, p *auth.Pr
 	if err != nil {
 		return err
 	}
+	if err := s.nameClients(r, p, sum.Tops[stats.KindClient]); err != nil {
+		return err
+	}
 	writeJSON(w, http.StatusOK, sum)
 	return nil
 }
@@ -75,6 +82,11 @@ func (s *Server) statsTop(w http.ResponseWriter, r *http.Request, p *auth.Princi
 	if err != nil {
 		return badRequest("%v", err)
 	}
+	if kind == stats.KindClient || kind == stats.KindRefused || kind == stats.KindBlockedClient {
+		if err := s.nameClients(r, p, es); err != nil {
+			return err
+		}
+	}
 	writeJSON(w, http.StatusOK, es)
 	return nil
 }
@@ -145,3 +157,86 @@ func (s *Server) statsBreakdown(w http.ResponseWriter, r *http.Request, p *auth.
 	writeJSON(w, http.StatusOK, es)
 	return nil
 }
+
+// nameClients gives client entries the host name Jarl's records have for
+// the address: the PTR record's target, or else the name of an A/AAAA
+// record with the address. It sends no DNS queries, and uses only records
+// the user may read. Anonymized clients (prefixes) get no name.
+func (s *Server) nameClients(r *http.Request, p *auth.Principal, es []stats.Entry) error {
+	if len(es) == 0 {
+		return nil
+	}
+	want := map[netip.Addr]bool{}
+	for _, e := range es {
+		if a, err := netip.ParseAddr(e.Key); err == nil {
+			want[a.Unmap()] = true
+		}
+	}
+	if len(want) == 0 {
+		return nil
+	}
+	st, err := s.state(r)
+	if err != nil {
+		return err
+	}
+	names := clientNames(st, want, func(rec *model.Record) bool { return canReadRecord(p, st, rec) })
+	for i, e := range es {
+		if a, err := netip.ParseAddr(e.Key); err == nil {
+			es[i].Name = names[a.Unmap()]
+		}
+	}
+	return nil
+}
+
+// clientNames finds names for the addresses in want (see nameClients).
+// Where several records match, the first in name order wins.
+func clientNames(st *model.State, want map[netip.Addr]bool, readable func(*model.Record) bool) map[netip.Addr]string {
+	ptr, host := map[netip.Addr]string{}, map[netip.Addr]string{}
+	var recs []*model.Record
+	for _, rec := range st.Records {
+		if !rec.Disabled && (rec.Type == "PTR" || rec.Type == "A" || rec.Type == "AAAA") {
+			recs = append(recs, rec)
+		}
+	}
+	slices.SortFunc(recs, func(a, b *model.Record) int {
+		if a.Name != b.Name {
+			if model.CanonicalLess(a.Name, b.Name) {
+				return -1
+			}
+			return 1
+		}
+		return strings.Compare(a.Data, b.Data)
+	})
+	for _, rec := range recs {
+		var a netip.Addr
+		var name string
+		if rec.Type == "PTR" {
+			var ok bool
+			if a, ok = dnsname.AddrFromReverse(rec.Name); !ok {
+				continue
+			}
+			name = rec.Data
+		} else {
+			var err error
+			if a, err = netip.ParseAddr(rec.Data); err != nil {
+				continue
+			}
+			name = rec.Name
+		}
+		a = a.Unmap()
+		m := host
+		if rec.Type == "PTR" {
+			m = ptr
+		}
+		if !want[a] || m[a] != "" || !readable(rec) {
+			continue
+		}
+		m[a] = dnsname.Display(name)
+	}
+	for a, n := range host {
+		if ptr[a] == "" {
+			ptr[a] = n
+		}
+	}
+	return ptr
+}

internal/server/present.go

@@ -9,6 +9,7 @@ import (
 	"jarl/internal/dnsname"
 	"jarl/internal/engine"
 	"jarl/internal/model"
+	"jarl/internal/namedconf"
 	"jarl/internal/render"
 	"jarl/internal/rr"
 	"jarl/internal/version"
@@ -100,6 +101,9 @@ func presentOption(st *model.State, o *model.Option) api.Option {
 	if c, ok := catalog.Default().Lookup(scope, o.Name); ok {
 		out.Description, out.Status = c.Description, c.Status
 	}
+	if f := namedconf.FormatValue(o.Name, o.Value); f != o.Value {
+		out.Formatted = f
+	}
 	return out
 }
 

internal/server/routes.go

@@ -56,6 +56,22 @@ func (s *Server) routes() {
 	m.HandleFunc("DELETE "+p+"/views/{id}", s.authed(s.deleteView))
 	m.HandleFunc("PUT "+p+"/views/{id}/color", s.authed(s.setViewColor))
 	// ACLs
+	// Blocking
+	m.HandleFunc("GET "+p+"/blocking/lists", s.authed(s.listBlocklists))
+	m.HandleFunc("POST "+p+"/blocking/lists", s.authed(s.createBlocklist))
+	m.HandleFunc("GET "+p+"/blocking/lists/{id}", s.authed(s.getBlocklist))
+	m.HandleFunc("PATCH "+p+"/blocking/lists/{id}", s.authed(s.updateBlocklist))
+	m.HandleFunc("DELETE "+p+"/blocking/lists/{id}", s.authed(s.deleteBlocklist))
+	m.HandleFunc("POST "+p+"/blocking/lists/{id}/refresh", s.authed(s.refreshBlocklist))
+	m.HandleFunc("GET "+p+"/blocking/rules", s.authed(s.listBlockRules))
+	m.HandleFunc("POST "+p+"/blocking/rules", s.authed(s.createBlockRule))
+	m.HandleFunc("DELETE "+p+"/blocking/rules", s.authed(s.deleteBlockRulesByName))
+	m.HandleFunc("PATCH "+p+"/blocking/rules/{id}", s.authed(s.updateBlockRule))
+	m.HandleFunc("DELETE "+p+"/blocking/rules/{id}", s.authed(s.deleteBlockRule))
+	m.HandleFunc("GET "+p+"/blocking/check", s.authed(s.checkBlocking))
+	m.HandleFunc("GET "+p+"/blocking/status", s.authed(s.blockingStatus))
+	m.HandleFunc("POST "+p+"/blocking/pause", s.authed(s.pauseBlocking(false)))
+	m.HandleFunc("POST "+p+"/blocking/resume", s.authed(s.pauseBlocking(true)))
 	m.HandleFunc("GET "+p+"/acls", s.authed(s.listACLs))
 	m.HandleFunc("POST "+p+"/acls", s.authed(s.createACL))
 	m.HandleFunc("GET "+p+"/acls/{id}", s.authed(s.getACL))

internal/server/stats_test.go

@@ -58,6 +58,17 @@ func TestStatsAPI(t *testing.T) {
 	if len(tops) != 2 || tops[0]["key"] != "www.example.com" {
 		t.Errorf("top names = %v", tops)
 	}
+	// Clients get the host name of Jarl's record for their address.
+	if c := e.list("/stats/top?kind=client&since=2h", e.token); len(c) != 1 || c[0]["name"] != nil {
+		t.Errorf("unnamed client = %v", c)
+	}
+	e.do("POST", "/zones", e.token, map[string]any{"name": "example.com", "records": []map[string]any{{"name": "ns1", "type": "A", "data": "192.0.2.1"}, {"name": "laptop", "type": "A", "data": "10.0.0.7"}}}, 201)
+	if c := e.list("/stats/top?kind=client&since=2h", e.token); len(c) != 1 || c[0]["name"] != "laptop.example.com" {
+		t.Errorf("named client = %v", c)
+	}
+	if sum := e.do("GET", "/stats/summary?since=2h", e.token, nil, 200); sum["tops"].(map[string]any)["client"].([]any)[0].(map[string]any)["name"] != "laptop.example.com" {
+		t.Errorf("summary clients = %v", sum["tops"])
+	}
 	if b := e.list("/stats/breakdown?group=zone&since=1h", e.token); len(b) != 2 || b[0]["key"] != "example.com" {
 		t.Errorf("zones = %v", b)
 	}

internal/stats/blocking_test.go

@@ -0,0 +1,114 @@
+package stats
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log/slog"
+	"net/netip"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestParseRewrite(t *testing.T) {
+	loc := time.UTC
+	// Real lines from named 9.20.24.
+	rw, ok := ParseRewrite(`09-Oct-2026 23:49:13.089 client @0x7bd607320000 127.0.0.1#56905 (x.ads.example): view internal: rpz QNAME NXDOMAIN rewrite x.ads.example/A/IN via x.ads.example.rules.jarl.invalid`, loc)
+	if !ok || rw.Client.String() != "127.0.0.1" || rw.Port != "56905" || rw.View != "internal" || rw.Name != "x.ads.example" || rw.Action != "NXDOMAIN" || policySource(rw.Via) != "rules" {
+		t.Errorf("rules rewrite: %+v (%s)", rw, policySource(rw.Via))
+	}
+	rw, ok = ParseRewrite(`09-Oct-2026 23:49:13.378 client @0x7bd607320000 10.0.0.9#57347 (Tracker.Example): rpz QNAME NXDOMAIN rewrite tracker.example/AAAA/IN via tracker.example.hagezi-pro.blocklist.jarl.invalid`, loc)
+	if !ok || rw.View != "" || rw.Name != "tracker.example" || policySource(rw.Via) != "hagezi-pro" {
+		t.Errorf("list rewrite: %+v (%s)", rw, policySource(rw.Via))
+	}
+	if policySource("ads.example.my-own-rpz.") != "ads.example.my-own-rpz" {
+		t.Error("a policy zone that isn't Jarl's")
+	}
+	if _, ok := ParseRewrite(`09-Oct-2026 23:49:13.378 client @0x7bd607320000 10.0.0.9#57347 (x): view internal: response: x IN A NOERROR 1 0 1 + (10.0.0.2)`, loc); ok {
+		t.Error("a response line parsed as a rewrite")
+	}
+}
+
+func TestCollectorBlocking(t *testing.T) {
+	ctx := context.Background()
+	loc := time.UTC
+	dir := t.TempDir()
+	logFile := filepath.Join(dir, "responses.log")
+	store, err := OpenStore(filepath.Join(dir, "stats.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+	named := newFakeNamed(t)
+	clk := &clock{time.Date(2026, 10, 5, 10, 0, 30, 0, loc)}
+	opts := Options{QueryLog: true, LogFile: logFile, StatisticsChannel: "unused", TopN: 5,
+		RetainMinute: 7 * 24 * time.Hour, RetainHour: 90 * 24 * time.Hour, RetainDay: 730 * 24 * time.Hour,
+		Exclude: []netip.Prefix{netip.MustParsePrefix("10.0.0.250/32")}, Location: loc}
+	c := NewCollector(store, opts, func() map[string][]string { return nil }, slog.New(slog.NewTextHandler(io.Discard, nil)))
+	c.poller.URL = named.srv.URL
+	c.now = clk.now
+	c.start(ctx)
+
+	at := time.Date(2026, 10, 5, 10, 0, 40, 0, loc).Format(logTimeLayout)
+	rewrite := func(client, port, name, action, via string) string {
+		return fmt.Sprintf("%s client @0x7f0000000000 %s#%s (%s): view internal: rpz QNAME %s rewrite %s/A/IN via %s\n", at, client, port, name, action, name, via)
+	}
+	response := func(client, port, name, rcode string) string {
+		return fmt.Sprintf("%s client @0x7f0000000000 %s#%s (%s): view internal: response: %s IN A %s 0 0 2 +E(0)K (10.0.0.2)\n", at, client, port, name, name, rcode)
+	}
+	f, _ := os.Create(logFile)
+	for _, l := range []string{
+		rewrite("10.0.0.5", "1001", "ads.example", "NXDOMAIN", "ads.example.hagezi.blocklist.jarl.invalid"),
+		response("10.0.0.5", "1001", "ads.example", "NXDOMAIN"),
+		rewrite("10.0.0.5", "1002", "x.ads.example", "NXDOMAIN", "x.ads.example.hagezi.blocklist.jarl.invalid"),
+		response("10.0.0.5", "1002", "x.ads.example", "NXDOMAIN"),
+		rewrite("10.0.0.6", "1003", "ads.example", "NXDOMAIN", "ads.example.rules.jarl.invalid"),
+		response("10.0.0.6", "1003", "ads.example", "NXDOMAIN"),
+		// An allow rule: answered normally, not blocked.
+		rewrite("10.0.0.6", "1004", "cdn.ads.example", "PASSTHRU", "cdn.ads.example.rules.jarl.invalid"),
+		response("10.0.0.6", "1004", "cdn.ads.example", "NOERROR"),
+		// A real NXDOMAIN.
+		response("10.0.0.6", "1005", "typo.example", "NXDOMAIN"),
+		// An excluded client.
+		rewrite("10.0.0.250", "1006", "ads.example", "NXDOMAIN", "ads.example.hagezi.blocklist.jarl.invalid"),
+		response("10.0.0.250", "1006", "ads.example", "NXDOMAIN"),
+	} {
+		f.WriteString(l)
+	}
+	f.Close()
+	c.readLog()
+	named.add(6, 4)
+	clk.t = time.Date(2026, 10, 5, 10, 1, 2, 0, loc)
+	c.flush(ctx, false)
+
+	m := time.Date(2026, 10, 5, 10, 0, 0, 0, loc).Unix()
+	got, _ := store.sums(ctx, ResMinute, m, m+60, "")
+	for k, v := range map[string]int64{"blocked": 3, "blocklist:hagezi": 2, "blocklist:rules": 1, "responses": 5} {
+		if got[k] != v {
+			t.Errorf("%s = %d, want %d (all: %v)", k, got[k], v, got)
+		}
+	}
+	if b, _ := store.TopsAt(ctx, ResHour, m, KindBlocked); len(b) != 2 || b[0] != (Entry{Key: "ads.example", Count: 2}) {
+		t.Errorf("blocked names = %v", b)
+	}
+	if bc, _ := store.TopsAt(ctx, ResHour, m, KindBlockedClient); len(bc) != 2 || bc[0] != (Entry{Key: "10.0.0.5", Count: 2}) {
+		t.Errorf("blocked clients = %v", bc)
+	}
+	if nx, _ := store.TopsAt(ctx, ResHour, m, KindNXDomain); len(nx) != 1 || nx[0].Key != "typo.example" {
+		t.Errorf("NXDOMAIN names should leave out blocked ones: %v", nx)
+	}
+	q := &Querier{Store: store, Opts: opts, Now: clk.now}
+	sum, err := q.Summary(ctx, time.Hour, 5)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// 6 queries, 4 NXDOMAIN of which 3 blocked.
+	if sum.Blocked != 3 || sum.BlockedRatio == nil || *sum.BlockedRatio != 0.5 || sum.NXDomainRatio == nil || *sum.NXDomainRatio != 1.0/6 {
+		t.Errorf("summary: blocked %d ratio %v nxdomain %v", sum.Blocked, sum.BlockedRatio, sum.NXDomainRatio)
+	}
+	if len(sum.Blocklists) != 2 || sum.Blocklists[0] != (Entry{Key: "hagezi", Count: 2}) || len(sum.Tops[KindBlocked]) != 2 {
+		t.Errorf("summary lists %v, tops %v", sum.Blocklists, sum.Tops[KindBlocked])
+	}
+}

internal/stats/collector.go

@@ -12,6 +12,8 @@ import (
 	"strings"
 	"sync"
 	"time"
+
+	"jarl/internal/blocking"
 )
 
 // Kinds of top lists.
@@ -21,10 +23,13 @@ const (
 	KindNXDomain = "nxdomain" // names answered with NXDOMAIN
 	KindServFail = "servfail" // names answered with SERVFAIL
 	KindRefused  = "refused"  // clients that were refused
+	KindBlocked  = "blocked"  // names blocked (docs/blocking.md)
+	// KindBlockedClient: clients with the most blocked queries.
+	KindBlockedClient = "blocked_client"
 )
 
 // Kinds lists the top-list kinds.
-var Kinds = []string{KindName, KindClient, KindNXDomain, KindServFail, KindRefused}
+var Kinds = []string{KindName, KindClient, KindNXDomain, KindServFail, KindRefused, KindBlocked, KindBlockedClient}
 
 // OtherZone is the zone key for names outside every local zone (answered
 // by recursion, or refused).
@@ -99,6 +104,9 @@ type Collector struct {
 	recentL  []int64 // response log lines per minute, last 10 minutes
 	linesMin int64
 	ensureAt time.Time
+	// rewritten holds queries named blocked (client#port|name) until their
+	// response line arrives.
+	rewritten map[string]bool
 }
 
 // maxKeys bounds the per-hour maps; rarely seen keys are dropped first.
@@ -296,8 +304,15 @@ func (c *Collector) HandleLine(line string) {
 func (c *Collector) handleLine(line string) {
 	ev, ok := ParseResponse(line, c.opts.Location)
 	if !ok {
+		if rw, ok := ParseRewrite(line, c.opts.Location); ok {
+			c.handleRewrite(rw)
+		}
 		return
 	}
+	blocked := c.rewritten[ev.Client.String()+"#"+ev.Port+"|"+ev.Name]
+	if blocked {
+		delete(c.rewritten, ev.Client.String()+"#"+ev.Port+"|"+ev.Name)
+	}
 	c.status.LinesRead++
 	c.linesMin++
 	t := ev.Time
@@ -324,12 +339,14 @@ func (c *Collector) handleLine(line string) {
 	tops := hours[hour]
 	tops[KindName][ev.Name]++
 	tops[KindClient][client]++
-	switch ev.RCode {
-	case "NXDOMAIN":
+	switch {
+	case blocked:
+		// Counted by handleRewrite; not a name that doesn't exist.
+	case ev.RCode == "NXDOMAIN":
 		tops[KindNXDomain][ev.Name]++
-	case "SERVFAIL":
+	case ev.RCode == "SERVFAIL":
 		tops[KindServFail][ev.Name]++
-	case "REFUSED":
+	case ev.RCode == "REFUSED":
 		tops[KindRefused][client]++
 	}
 	for _, m := range tops {
@@ -339,6 +356,49 @@ func (c *Collector) handleLine(line string) {
 	}
 }
 
+// handleRewrite counts a query that blocking answered: "blocked", and
+// "blocklist:NAME" for the list (or "rules") that matched.
+func (c *Collector) handleRewrite(rw Rewrite) {
+	if rw.Action == "PASSTHRU" {
+		return // an allow rule: answered normally
+	}
+	for _, p := range c.opts.Exclude {
+		if p.Contains(rw.Client) {
+			return
+		}
+	}
+	if c.rewritten == nil || len(c.rewritten) > 10_000 {
+		// Rewrites whose response line never came (named only logs
+		// responses while response logging is on) don't pile up.
+		c.rewritten = map[string]bool{}
+	}
+	c.rewritten[rw.Client.String()+"#"+rw.Port+"|"+rw.Name] = true
+	minute, hour := c.minuteOf(rw.Time), c.hourOf(rw.Time)
+	c.count(minute, "blocked", 1)
+	c.count(minute, "blocklist:"+policySource(rw.Via), 1)
+	hours := c.hours
+	if hour < c.liveHour {
+		hours = c.late
+	}
+	hours[hour] = c.hourMaps(hours, hour)
+	hours[hour][KindBlocked][rw.Name]++
+	hours[hour][KindBlockedClient][clientKey(rw.Client, c.opts.Anonymize)]++
+}
+
+// policySource names what a rewrite came from: a blocklist's name, "rules"
+// for the rules entered in Jarl, or the policy zone for others.
+func policySource(via string) string {
+	via = strings.TrimSuffix(via, ".")
+	if strings.HasSuffix(via, "."+blocking.RulesZone) {
+		return "rules"
+	}
+	if i := strings.LastIndex(via, ".blocklist.jarl.invalid"); i > 0 && i+len(".blocklist.jarl.invalid") == len(via) {
+		rest := via[:i]
+		return rest[strings.LastIndex(rest, ".")+1:]
+	}
+	return via
+}
+
 // shrink drops the rarest keys until the map is well under maxKeys.
 func shrink(m map[string]int64) {
 	for limit := int64(1); len(m) > maxKeys*8/10; limit++ {
@@ -528,7 +588,7 @@ func (c *Collector) updateWarnings() {
 func top(m map[string]int64, n int) []Entry {
 	out := make([]Entry, 0, len(m))
 	for k, v := range m {
-		out = append(out, Entry{k, v})
+		out = append(out, Entry{Key: k, Count: v})
 	}
 	slices.SortFunc(out, func(a, b Entry) int {
 		if a.Count != b.Count {

internal/stats/collector_test.go

@@ -118,7 +118,7 @@ func TestCollector(t *testing.T) {
 		}
 	}
 	names, _ := store.TopsAt(ctx, ResHour, m, KindName)
-	if len(names) != 3 || names[0] != (Entry{"nas.adbraun.lol", 2}) {
+	if len(names) != 3 || names[0] != (Entry{Key: "nas.adbraun.lol", Count: 2}) {
 		t.Errorf("hour names = %v", names)
 	}
 	if nx, _ := store.TopsAt(ctx, ResHour, m, KindNXDomain); len(nx) != 1 || nx[0].Key != "nope.adbraun.lol" {
@@ -133,7 +133,7 @@ func TestCollector(t *testing.T) {
 	clk.t = time.Date(2026, 10, 5, 11, 0, 2, 0, loc)
 	c.flush(ctx, false)
 	day := time.Date(2026, 10, 5, 0, 0, 0, 0, loc).Unix()
-	if d, _ := store.TopsAt(ctx, ResDay, day, KindName); len(d) == 0 || d[0] != (Entry{"nas.adbraun.lol", 3}) {
+	if d, _ := store.TopsAt(ctx, ResDay, day, KindName); len(d) == 0 || d[0] != (Entry{Key: "nas.adbraun.lol", Count: 3}) {
 		t.Errorf("day names after the hour = %v", d)
 	}
 	if v, _ := store.sums(ctx, ResDay, day, day+1, "queries"); v["queries"] != 7 {
@@ -149,14 +149,14 @@ func TestCollector(t *testing.T) {
 	c2.readLog()
 	clk.t = time.Date(2026, 10, 5, 11, 3, 2, 0, loc)
 	c2.flush(ctx, false)
-	if h, _ := store.TopsAt(ctx, ResHour, m, KindName); len(h) == 0 || h[0] != (Entry{"nas.adbraun.lol", 4}) {
+	if h, _ := store.TopsAt(ctx, ResHour, m, KindName); len(h) == 0 || h[0] != (Entry{Key: "nas.adbraun.lol", Count: 4}) {
 		t.Errorf("hour 10 after late line = %v", h)
 	}
-	if d, _ := store.TopsAt(ctx, ResDay, day, KindName); d[0] != (Entry{"nas.adbraun.lol", 4}) {
+	if d, _ := store.TopsAt(ctx, ResDay, day, KindName); d[0] != (Entry{Key: "nas.adbraun.lol", Count: 4}) {
 		t.Errorf("day after late line = %v", d)
 	}
 	h11 := time.Date(2026, 10, 5, 11, 0, 0, 0, loc).Unix()
-	if h, _ := store.TopsAt(ctx, ResHour, h11, KindName); len(h) != 1 || h[0] != (Entry{"printer.adbraun.lol", 2}) {
+	if h, _ := store.TopsAt(ctx, ResHour, h11, KindName); len(h) != 1 || h[0] != (Entry{Key: "printer.adbraun.lol", Count: 2}) {
 		t.Errorf("hour 11 continued after restart = %v", h)
 	}
 
@@ -198,7 +198,7 @@ func TestCollector(t *testing.T) {
 		t.Errorf("heatmap Monday 10h=%v 11h=%v Thu 3h=%v", hm.Avg[0][10], hm.Avg[0][11], hm.Avg[3][3])
 	}
 	b, _ := q.Breakdown(ctx, "zone", 24*time.Hour)
-	if len(b) != 2 || b[0] != (Entry{"adbraun.lol", 7}) || b[1] != (Entry{OtherZone, 1}) {
+	if len(b) != 2 || b[0] != (Entry{Key: "adbraun.lol", Count: 7}) || b[1] != (Entry{Key: OtherZone, Count: 1}) {
 		t.Errorf("zone breakdown = %v", b)
 	}
 

internal/stats/parse.go

@@ -11,18 +11,36 @@ import (
 type Event struct {
 	Time   time.Time
 	Client netip.Addr
+	Port   string // the client's port: with Client and Name, it ties an RPZ rewrite to its response
 	View   string // "" without views
 	Name   string // lowercase, without the final dot ("." for the root)
 	Type   string // e.g. A, AAAA, PTR
 	RCode  string // e.g. NOERROR, NXDOMAIN
 }
 
+// Rewrite is a response policy (RPZ) rewrite named logged: blocking.
+type Rewrite struct {
+	Time   time.Time
+	Client netip.Addr
+	Port   string
+	View   string
+	Name   string // the query name, normalized like Event.Name
+	Action string // NXDOMAIN, NODATA, PASSTHRU, DROP, ...
+	Via    string // the policy zone entry: OWNER.ZONE
+}
+
 // responseRe matches named's response log lines (BIND 9.20, print-time):
 //
 //	07-Oct-2026 19:46:22.195 client @0x7135... 10.10.0.37#51709 (nas.adbraun.lol): view internal: response: nas.adbraun.lol IN A NOERROR 1 0 1 +E(0)K (10.10.0.2)
 //
 // The "view NAME: " part is missing when no views are configured.
-var responseRe = regexp.MustCompile(`^(\d{2}-[A-Za-z]{3}-\d{4} \d{2}:\d{2}:\d{2}\.\d{3}) client @0x[0-9a-fA-F]+ (\S+)#\d+ \(.*?\): (?:view (.+?): )?response: (\S+) (\S+) (\S+) ([A-Z0-9]+) `)
+var responseRe = regexp.MustCompile(`^(\d{2}-[A-Za-z]{3}-\d{4} \d{2}:\d{2}:\d{2}\.\d{3}) client @0x[0-9a-fA-F]+ (\S+)#(\d+) \(.*?\): (?:view (.+?): )?response: (\S+) (\S+) (\S+) ([A-Z0-9]+) `)
+
+// rewriteRe matches named's RPZ rewrite lines (category rpz), logged just
+// before the response line of the same query:
+//
+//	09-Oct-2026 23:49:13.698 client @0x7135... 10.10.0.37#54468 (ads.example): view internal: rpz QNAME NXDOMAIN rewrite ads.example/A/IN via ads.example.hagezi.blocklist.jarl.invalid
+var rewriteRe = regexp.MustCompile(`^(\d{2}-[A-Za-z]{3}-\d{4} \d{2}:\d{2}:\d{2}\.\d{3}) client @0x[0-9a-fA-F]+ (\S+)#(\d+) \((.*?)\): (?:view (.+?): )?rpz \S+ (\S+) rewrite \S+ via (\S+)`)
 
 const logTimeLayout = "02-Jan-2006 15:04:05.000"
 
@@ -44,13 +62,31 @@ func ParseResponse(line string, loc *time.Location) (ev Event, ok bool) {
 	return Event{
 		Time:   t,
 		Client: client.Unmap(),
-		View:   m[3],
-		Name:   normalizeName(m[4]),
-		Type:   m[6],
-		RCode:  m[7],
+		Port:   m[3],
+		View:   m[4],
+		Name:   normalizeName(m[5]),
+		Type:   m[7],
+		RCode:  m[8],
 	}, true
 }
 
+// ParseRewrite parses an RPZ rewrite log line.
+func ParseRewrite(line string, loc *time.Location) (rw Rewrite, ok bool) {
+	m := rewriteRe.FindStringSubmatch(line)
+	if m == nil {
+		return rw, false
+	}
+	t, err := time.ParseInLocation(logTimeLayout, m[1], loc)
+	if err != nil {
+		return rw, false
+	}
+	client, err := netip.ParseAddr(m[2])
+	if err != nil {
+		return rw, false
+	}
+	return Rewrite{Time: t, Client: client.Unmap(), Port: m[3], Name: normalizeName(m[4]), View: m[5], Action: m[6], Via: strings.ToLower(m[7])}, true
+}
+
 func normalizeName(n string) string {
 	n = strings.ToLower(n)
 	if n == "." {

internal/stats/query.go

@@ -128,7 +128,7 @@ func sorted(m map[string]int64, prefix string) []Entry {
 	out := []Entry{}
 	for k, v := range m {
 		if strings.HasPrefix(k, prefix) && v != 0 {
-			out = append(out, Entry{strings.TrimPrefix(k, prefix), v})
+			out = append(out, Entry{Key: strings.TrimPrefix(k, prefix), Count: v})
 		}
 	}
 	slices.SortFunc(out, func(a, b Entry) int {
@@ -160,7 +160,12 @@ type Summary struct {
 	Answers       []Entry  `json:"answers"`   // authoritative, recursive
 	Transport     []Entry  `json:"transport"` // udp, tcp
 	CacheHitRatio *float64 `json:"cache_hit_ratio,omitempty"`
+	// NXDomainRatio leaves out answers blocking gave (which are
+	// NXDOMAIN too); Blocked counts those (docs/blocking.md).
 	NXDomainRatio *float64           `json:"nxdomain_ratio,omitempty"`
+	Blocked       int64              `json:"blocked"`
+	BlockedRatio  *float64           `json:"blocked_ratio,omitempty"`
+	Blocklists    []Entry            `json:"blocklists,omitempty"`
 	Tops          map[string][]Entry `json:"tops,omitempty"`
 }
 
@@ -181,9 +186,14 @@ func (q *Querier) Summary(ctx context.Context, since time.Duration, topLimit int
 		r := float64(h) / float64(h+m)
 		s.CacheHitRatio = &r
 	}
+	s.Blocked, s.Blocklists = all["blocked"], sorted(all, "blocklist:")
 	if s.Queries > 0 {
-		r := float64(all["rcode:NXDOMAIN"]) / float64(s.Queries)
+		r := float64(max(all["rcode:NXDOMAIN"]-s.Blocked, 0)) / float64(s.Queries)
 		s.NXDomainRatio = &r
+		if s.Blocked > 0 {
+			b := float64(s.Blocked) / float64(s.Queries)
+			s.BlockedRatio = &b
+		}
 	}
 	per, err := q.Store.series(ctx, res, from, to, "queries")
 	if err != nil {
@@ -209,7 +219,7 @@ func (q *Querier) Summary(ctx context.Context, since time.Duration, topLimit int
 	}
 	if topLimit > 0 {
 		s.Tops = map[string][]Entry{}
-		for _, k := range []string{KindName, KindClient, KindNXDomain} {
+		for _, k := range []string{KindName, KindClient, KindNXDomain, KindBlocked} {
 			es, err := q.Top(ctx, k, since, topLimit)
 			if err != nil {
 				return nil, err
@@ -246,7 +256,7 @@ func (q *Querier) Breakdown(ctx context.Context, group string, since time.Durati
 }
 
 // Groups are the counter groups Breakdown accepts.
-var Groups = []string{"qtype", "rcode", "view", "zone", "answer", "transport", "rtt", "dnssec", "cache", "ratelimit"}
+var Groups = []string{"qtype", "rcode", "view", "zone", "answer", "transport", "rtt", "dnssec", "cache", "ratelimit", "blocklist"}
 
 // Timeline is a set of series over time.
 type Timeline struct {

internal/stats/store.go

@@ -135,6 +135,9 @@ type topsWrite struct {
 type Entry struct {
 	Key   string `json:"key"`
 	Count int64  `json:"count"`
+	// Name is a client's host name, from Jarl's own records (set by the
+	// API for client lists).
+	Name string `json:"name,omitempty"`
 }
 
 // AddCounters adds values to the counters of a bucket.

internal/store/blocklists.go

@@ -0,0 +1,42 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+
+	"jarl/internal/model"
+)
+
+// BlocklistStatuses returns the download status of every blocklist that
+// has one.
+func (s *Store) BlocklistStatuses(ctx context.Context) (map[int64]*model.BlocklistStatus, error) {
+	rows, err := s.db.QueryContext(ctx, `SELECT id, url, etag, last_modified, checked_at, updated_at, entries, records, skipped, sha256, error FROM blocklist_status`)
+	if err != nil {
+		return nil, err
+	}
+	out := map[int64]*model.BlocklistStatus{}
+	for rows.Next() {
+		st := &model.BlocklistStatus{}
+		var checked, updated sql.NullString
+		if err := rows.Scan(&st.ID, &st.URL, &st.ETag, &st.LastModified, &checked, &updated, &st.Entries, &st.Records, &st.Skipped, &st.SHA256, &st.Error); err != nil {
+			rows.Close()
+			return nil, err
+		}
+		st.CheckedAt, st.UpdatedAt = parseTSPtr(checked), parseTSPtr(updated)
+		out[st.ID] = st
+	}
+	return out, closeRows(rows)
+}
+
+// SetBlocklistStatus stores a blocklist's download status.
+func (s *Store) SetBlocklistStatus(ctx context.Context, st *model.BlocklistStatus) error {
+	_, err := s.db.ExecContext(ctx, `INSERT OR REPLACE INTO blocklist_status (id, url, etag, last_modified, checked_at, updated_at, entries, records, skipped, sha256, error) VALUES (?,?,?,?,?,?,?,?,?,?,?)`,
+		st.ID, st.URL, st.ETag, st.LastModified, tsPtr(st.CheckedAt), tsPtr(st.UpdatedAt), st.Entries, st.Records, st.Skipped, st.SHA256, st.Error)
+	return err
+}
+
+// DeleteBlocklistStatus forgets a deleted blocklist's status.
+func (s *Store) DeleteBlocklistStatus(ctx context.Context, id int64) error {
+	_, err := s.db.ExecContext(ctx, `DELETE FROM blocklist_status WHERE id = ?`, id)
+	return err
+}

internal/store/state.go

@@ -149,6 +149,44 @@ func loadState(ctx context.Context, e execer) (*model.State, error) {
 	if err := closeRows(rows); err != nil {
 		return nil, err
 	}
+
+	rows, err = e.QueryContext(ctx, `SELECT id, name, url, view_ids, disabled, comment, version, created_at, updated_at, created_by, updated_by FROM blocklists`)
+	if err != nil {
+		return nil, err
+	}
+	for rows.Next() {
+		b := &model.Blocklist{}
+		var views, ca, ua string
+		if err := rows.Scan(&b.ID, &b.Name, &b.URL, &views, &b.Disabled, &b.Comment, &b.Version, &ca, &ua, &b.CreatedBy, &b.UpdatedBy); err != nil {
+			rows.Close()
+			return nil, err
+		}
+		json.Unmarshal([]byte(views), &b.ViewIDs)
+		b.CreatedAt, b.UpdatedAt = parseTS(ca), parseTS(ua)
+		st.Blocklists[b.ID] = b
+	}
+	if err := closeRows(rows); err != nil {
+		return nil, err
+	}
+
+	rows, err = e.QueryContext(ctx, `SELECT id, name, action, exact, view_ids, comment, version, created_at, updated_at, created_by, updated_by FROM block_rules`)
+	if err != nil {
+		return nil, err
+	}
+	for rows.Next() {
+		r := &model.BlockRule{}
+		var views, ca, ua string
+		if err := rows.Scan(&r.ID, &r.Name, &r.Action, &r.Exact, &views, &r.Comment, &r.Version, &ca, &ua, &r.CreatedBy, &r.UpdatedBy); err != nil {
+			rows.Close()
+			return nil, err
+		}
+		json.Unmarshal([]byte(views), &r.ViewIDs)
+		r.CreatedAt, r.UpdatedAt = parseTS(ca), parseTS(ua)
+		st.BlockRules[r.ID] = r
+	}
+	if err := closeRows(rows); err != nil {
+		return nil, err
+	}
 	return st, nil
 }
 
@@ -166,7 +204,7 @@ func (t *Tx) SaveState(old, new *model.State) error {
 // ReplaceState replaces the stored configuration with st (used by import
 // and tests).
 func (t *Tx) ReplaceState(st *model.State) error {
-	for _, tbl := range []string{"views", "acls", "tsig_keys", "zones", "records", "options"} {
+	for _, tbl := range []string{"views", "acls", "tsig_keys", "zones", "records", "options", "blocklists", "block_rules"} {
 		if _, err := t.tx.ExecContext(t.ctx, "DELETE FROM "+tbl); err != nil {
 			return err
 		}
@@ -226,11 +264,32 @@ func saveState(ctx context.Context, e execer, old, new *model.State) error {
 	}, func(id int64) error { return del(ctx, e, "records", id) }); err != nil {
 		return err
 	}
-	return diffMap(old.Options, new.Options, func(o *model.Option) error {
+	if err := diffMap(old.Options, new.Options, func(o *model.Option) error {
 		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO options (id, scope, scope_id, name, value, position, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?,?)`,
 			o.ID, o.Scope, o.ScopeID, o.Name, o.Value, o.Position, o.Comment, o.Version, ts(o.CreatedAt), ts(o.UpdatedAt), o.CreatedBy, o.UpdatedBy)
 		return err
-	}, func(id int64) error { return del(ctx, e, "options", id) })
+	}, func(id int64) error { return del(ctx, e, "options", id) }); err != nil {
+		return err
+	}
+	if err := diffMap(old.Blocklists, new.Blocklists, func(b *model.Blocklist) error {
+		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO blocklists (id, name, url, view_ids, disabled, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?)`,
+			b.ID, b.Name, b.URL, jsonText(nonNilIDs(b.ViewIDs)), b.Disabled, b.Comment, b.Version, ts(b.CreatedAt), ts(b.UpdatedAt), b.CreatedBy, b.UpdatedBy)
+		return err
+	}, func(id int64) error { return del(ctx, e, "blocklists", id) }); err != nil {
+		return err
+	}
+	return diffMap(old.BlockRules, new.BlockRules, func(r *model.BlockRule) error {
+		_, err := e.ExecContext(ctx, `INSERT OR REPLACE INTO block_rules (id, name, action, exact, view_ids, comment, version, created_at, updated_at, created_by, updated_by) VALUES (?,?,?,?,?,?,?,?,?,?,?)`,
+			r.ID, r.Name, r.Action, r.Exact, jsonText(nonNilIDs(r.ViewIDs)), r.Comment, r.Version, ts(r.CreatedAt), ts(r.UpdatedAt), r.CreatedBy, r.UpdatedBy)
+		return err
+	}, func(id int64) error { return del(ctx, e, "block_rules", id) })
+}
+
+func nonNilIDs(ids []int64) []int64 {
+	if ids == nil {
+		return []int64{}
+	}
+	return ids
 }
 
 func nonNil(s []string) []string {

internal/store/store.go

@@ -263,6 +263,43 @@ CREATE TABLE recovery_codes (
 	// 5: disabled records, kept but left out of the zone.
 	`
 ALTER TABLE records ADD COLUMN disabled INTEGER NOT NULL DEFAULT 0;
+`,
+	// 6: blocking (docs/blocking.md). blocklist_status holds what jarld
+	// learns downloading lists; it is not configuration.
+	`
+CREATE TABLE blocklists (
+	id INTEGER PRIMARY KEY,
+	name TEXT NOT NULL,
+	url TEXT NOT NULL,
+	view_ids TEXT NOT NULL DEFAULT '[]',
+	disabled INTEGER NOT NULL DEFAULT 0,
+	comment TEXT NOT NULL DEFAULT '',
+	version INTEGER NOT NULL, created_at TEXT NOT NULL, updated_at TEXT NOT NULL,
+	created_by TEXT NOT NULL DEFAULT '', updated_by TEXT NOT NULL DEFAULT ''
+);
+CREATE TABLE block_rules (
+	id INTEGER PRIMARY KEY,
+	name TEXT NOT NULL,
+	action TEXT NOT NULL,
+	exact INTEGER NOT NULL DEFAULT 0,
+	view_ids TEXT NOT NULL DEFAULT '[]',
+	comment TEXT NOT NULL DEFAULT '',
+	version INTEGER NOT NULL, created_at TEXT NOT NULL, updated_at TEXT NOT NULL,
+	created_by TEXT NOT NULL DEFAULT '', updated_by TEXT NOT NULL DEFAULT ''
+);
+CREATE TABLE blocklist_status (
+	id INTEGER PRIMARY KEY,
+	url TEXT NOT NULL DEFAULT '',
+	etag TEXT NOT NULL DEFAULT '',
+	last_modified TEXT NOT NULL DEFAULT '',
+	checked_at TEXT,
+	updated_at TEXT,
+	entries INTEGER NOT NULL DEFAULT 0,
+	records INTEGER NOT NULL DEFAULT 0,
+	skipped INTEGER NOT NULL DEFAULT 0,
+	sha256 TEXT NOT NULL DEFAULT '',
+	error TEXT NOT NULL DEFAULT ''
+);
 `,
 }
 

internal/validate/blocking.go

@@ -0,0 +1,93 @@
+package validate
+
+import (
+	"strings"
+
+	"jarl/internal/model"
+)
+
+// checkBlocking checks blocklists and block/allow rules (docs/blocking.md).
+func (c *checker) checkBlocking() {
+	viewNames := func(ids []int64) string {
+		var names []string
+		for _, id := range ids {
+			if v := c.s.Views[id]; v != nil {
+				names = append(names, v.Name)
+			}
+		}
+		return strings.Join(names, ", ")
+	}
+	used := map[int64]bool{} // views (0: the server) with blocking
+	// what describes where something applies, and warns when it can't
+	// have any effect.
+	effective := func(objType string, id int64, label string, ids []int64) []int64 {
+		for _, vid := range ids {
+			if c.s.Views[vid] == nil {
+				c.errf("blocking_view_missing", objType, id, "%s names view %d, which doesn't exist", label, vid)
+			}
+		}
+		views := c.s.BlockingViews(ids)
+		if len(views) == 0 {
+			c.warnf("blocking_no_view", objType, id, "%s has no effect: no view offers recursion, and blocking only changes answers to recursive queries", label)
+		}
+		var idle []int64
+		for _, vid := range views {
+			if !c.s.RecursionOn(vid) {
+				idle = append(idle, vid)
+			}
+		}
+		if len(idle) > 0 {
+			c.warnf("blocking_no_recursion", objType, id, "%s has no effect in view %s: it doesn't offer recursion, and blocking only changes answers to recursive queries", label, viewNames(idle))
+		}
+		for _, vid := range views {
+			used[vid] = true
+		}
+		return views
+	}
+	for _, b := range c.s.SortedBlocklists() {
+		if !b.Disabled {
+			effective("blocklist", b.ID, "blocklist "+b.Name, b.ViewIDs)
+		}
+	}
+	// One rule per name and view: two would compete for the same entries
+	// of the policy zone.
+	seen := map[string]*model.BlockRule{} // view|name -> first rule
+	for _, r := range c.s.SortedBlockRules() {
+		label := "the rule for " + r.Name
+		for _, vid := range effective("blockrule", r.ID, label, r.ViewIDs) {
+			key := c.blockingScope(vid) + "|" + r.Name
+			if first := seen[key]; first != nil && first.ID != r.ID {
+				where := ""
+				if v := c.s.Views[vid]; v != nil {
+					where = " in view " + v.Name
+				}
+				c.errf("blocking_rule_duplicate", "blockrule", r.ID, "there are two rules for %s%s (%s and %s); keep one", r.Name, where, first.Action, r.Action)
+				continue
+			}
+			seen[key] = r
+		}
+	}
+	// Jarl writes the response-policy statement where blocking is used;
+	// named allows one per view (or for the server).
+	for vid := range used {
+		if o := c.s.FindOption(model.ScopeView, vid, "response-policy"); vid != 0 && o != nil {
+			p := c.errf("blocking_response_policy", "option", o.ID, "view %s has a response-policy option, but Jarl's blocking writes that statement there; remove the option (or the blocking that applies to this view)", c.s.Views[vid].Name)
+			p.View = c.s.Views[vid].Name
+		}
+	}
+	if o := c.s.FindOption(model.ScopeOptions, 0, "response-policy"); o != nil && len(used) > 0 {
+		c.errf("blocking_response_policy", "option", o.ID, "the server has a response-policy option, which Jarl's blocking replaces wherever it is used; remove the option, or set up your policy zones with Jarl's blocking instead")
+	}
+	for _, z := range c.s.Zones {
+		if n := strings.TrimSuffix(z.Name, "."); n == "jarl.invalid" || strings.HasSuffix(n, ".jarl.invalid") {
+			c.zoneProblem(z, Error, "zone_name_reserved", "zone names under jarl.invalid are reserved for Jarl's blocking")
+		}
+	}
+}
+
+func (c *checker) blockingScope(viewID int64) string {
+	if v := c.s.Views[viewID]; v != nil {
+		return v.Name
+	}
+	return ""
+}

internal/validate/validate.go

@@ -137,6 +137,7 @@ func State(s *model.State, opts Options) []Problem {
 	c.checkOptions()
 	c.checkSecurity()
 	c.checkDNSSEC()
+	c.checkBlocking()
 	sortProblems(c.problems)
 	return c.problems
 }

internal/web/static/assets/app.js

@@ -1,7 +1,7 @@
 // Jarl web UI: router, layout and login.
-import { h, mount, toast, errorBox, plural, lastList } from "./ui.js";
+import { h, mount, toast, errorBox, plural, lastList, modal } from "./ui.js";
 import { wordmark, logo } from "./brand.js";
-import { api, get, state, loadDraft, onChange, setUnauthorizedHandler, setImmediate, setCodePrompt } from "./api.js";
+import { api, get, state, loadDraft, onChange, setUnauthorizedHandler, setImmediate, setCodePrompt, useDraft } from "./api.js";
 import * as totp from "./totp.js";
 import * as dashboard from "./pages/dashboard.js";
 import * as zones from "./pages/zones.js";
@@ -17,6 +17,7 @@ import * as users from "./pages/users.js";
 import * as account from "./pages/account.js";
 import * as search from "./pages/search.js";
 import * as stats from "./pages/stats.js";
+import * as blocking from "./pages/blocking.js";
 
 const routes = [
   { pattern: /^$/, page: dashboard, nav: "dashboard" },
@@ -34,12 +35,14 @@ const routes = [
   { pattern: /^account$/, page: account, nav: "account" },
   { pattern: /^search$/, page: search, nav: "" },
   { pattern: /^stats$/, page: stats, nav: "stats" },
+  { pattern: /^blocking$/, page: blocking, nav: "blocking" },
 ];
 
 const navItems = [
   ["dashboard", "#/", "Dashboard"],
   ["stats", "#/stats", "Statistics"],
   ["zones", "#/zones", "Zones"],
+  ["blocking", "#/blocking", "Blocking"],
   ["views", "#/views", "Views"],
   ["acls", "#/acls", "ACLs"],
   ["keys", "#/keys", "TSIG keys"],
@@ -204,7 +207,28 @@ function renderBar() {
   mount(barEl, n > 0 ? h("div", { class: "pending-bar" },
     h("strong", null, plural(n, "pending change")),
     h("span", { class: "muted" }, "Your edits are collected in changeset #" + d.id + " and are not live yet."),
-    h("a", { class: "button primary small", href: "#/changes" }, "Review & apply")) : null);
+    h("a", { class: "button small", href: "#/changes" }, "Review"),
+    h("button", { class: "primary small apply-now", title: "Apply the pending changes now, without reviewing them first", onclick: (ev) => applyDraft(ev.target, d) }, "Apply now")) : null);
+}
+
+// applyDraft applies the draft changeset from the banner and stays on the
+// page. If it is refused, a dialog says why and links to Changes.
+async function applyDraft(btn, d) {
+  btn.disabled = true;
+  btn.textContent = "Applying…";
+  try {
+    const r = await api("POST", "/changesets/" + d.id + "/apply", { body: {} });
+    const res = r.result || {};
+    toast("Applied changeset #" + d.id + (res.reloaded && res.reloaded.length ? " — named reloaded" : ""));
+    (r.warnings || []).forEach((w) => toast(w, "warn", 10000));
+    useDraft(null);
+    rerender();
+  } catch (e) {
+    btn.disabled = false;
+    btn.textContent = "Apply now";
+    const review = await modal("The changes were not applied", errorBox(e), [{ label: "Close", value: false }, { label: "Review changes", kind: "primary", value: true }], { wide: true });
+    if (review) location.hash = "#/changes";
+  }
 }
 
 async function logout() {

internal/web/static/assets/charts.js

@@ -324,9 +324,11 @@ export function barList(entries, { total, label = (k) => k, empty = "No data yet
     const share = sum ? (e.count / sum) * 100 : 0;
     const name = label(e.key);
     const link = href ? href(e.key) : null;
-    return h("li", { title: name + ": " + e.count.toLocaleString() + " (" + share.toFixed(1) + "%)" },
+    // Clients Jarl has a host name for: the name, then the address.
+    const shown = e.name ? [e.name, h("span", { class: "muted" }, " " + name)] : name;
+    return h("li", { title: (e.name ? e.name + " (" + name + ")" : name) + ": " + e.count.toLocaleString() + " (" + share.toFixed(1) + "%)" },
       h("div", { class: "bar-text" },
-        link ? h("a", { href: link, class: "bar-label" }, name) : h("span", { class: "bar-label" }, name),
+        link ? h("a", { href: link, class: "bar-label" }, shown) : h("span", { class: "bar-label" }, shown),
         h("span", { class: "bar-value" }, compact(e.count), h("span", { class: "muted" }, " · " + share.toFixed(share < 10 ? 1 : 0) + "%"))),
       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/blocking.js

@@ -0,0 +1,318 @@
+// Blocking: your block/allow rules and blocklists (docs/blocking.md).
+import { h, mount, table, field, input, select, checkbox, toast, errorBox, badge, confirmDialog, modal, relTime, time } from "../ui.js";
+import { get, change, describeResult, draftQuery, can, api } from "../api.js";
+import { rerender } from "../app.js";
+import { pendingBadge } from "./zones.js";
+
+// Well-known lists in Adblock format (they say which entries cover
+// subdomains). Sizes change; these are rough guides.
+const suggestions = [
+  ["hagezi-light", "https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/light.txt", "Hagezi Light: small, very few false positives"],
+  ["hagezi-multi", "https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/multi.txt", "Hagezi Multi Normal: ads, tracking, malware; a good default"],
+  ["hagezi-pro", "https://raw.githubusercontent.com/hagezi/dns-blocklists/main/adblock/pro.txt", "Hagezi Pro: more thorough, occasionally blocks something wanted"],
+  ["oisd-small", "https://small.oisd.nl/", "OISD Small: ads and tracking, very few false positives"],
+];
+
+const stateBadge = {
+  ok: ["in use", "ok"], waiting: ["downloading", "accent"], error: ["update failed", "err"],
+  disabled: ["disabled", ""], idle: ["no effect", "warn"],
+};
+
+let refreshTimer = null;
+
+export async function render(el, params, query) {
+  clearTimeout(refreshTimer);
+  const [lists, rules, views, status] = await Promise.all([get("/blocking/lists", draftQuery()), get("/blocking/rules", draftQuery()), get("/views"), get("/blocking/status")]);
+  const writable = can("blocking", true);
+  const recursive = lists.concat(rules).find((x) => x.auto_views);
+  const autoViews = recursive ? recursive.views : null;
+
+  const checkOut = h("div");
+  const checkName = input({ type: "search", placeholder: "ads.example.com", class: "mono", value: (query && query.get("check")) || "" });
+  const runCheck = async (ev) => {
+    if (ev) ev.preventDefault();
+    const name = checkName.value.trim();
+    if (!name) return;
+    try {
+      const res = await get("/blocking/check", { name });
+      mount(checkOut, checkResult(name, res, rules, writable));
+    } catch (e) { mount(checkOut, errorBox(e)); }
+  };
+
+  const paused = status.paused_until;
+  mount(el,
+    h("div", { class: "page-head" },
+      h("div", { class: "grow" }, h("h1", null, "Blocking"),
+        h("div", { class: "muted" }, "Answer \"doesn't exist\" for ads, trackers and malware, for the devices that use this server to resolve names. Your rules come first, then the blocklists.")),
+      writable && !paused && (lists.length || rules.length) ? pauseControls() : null),
+    paused ? h("div", { class: "msg warn" },
+      h("strong", null, "Blocking is paused until " + new Date(paused).toLocaleTimeString([], { hour: "2-digit", minute: "2-digit" }) + ": "),
+      "every name is answered normally. It resumes by itself. ",
+      writable ? h("button", { class: "small", onclick: () => pause(0) }, "Resume now") : null) : null,
+    h("div", { class: "panel" },
+      h("form", { class: "actions", onsubmit: runCheck },
+        h("label", { class: "muted" }, "Check a name"), checkName, h("button", { type: "submit" }, "Check")),
+      checkOut),
+    rulesPanel(rules, views, autoViews, writable),
+    listsPanel(lists, views, autoViews, writable));
+  if (checkName.value) runCheck();
+
+  // Lists are downloaded in the background, and a pause ends by itself:
+  // show it when it happens.
+  let wait = 0;
+  if (lists.some((l) => l.state === "waiting")) wait = 4000;
+  if (paused) wait = Math.max(1000, Math.min(wait || Infinity, new Date(paused) - Date.now() + 3000));
+  if (wait) refreshTimer = setTimeout(() => { if (location.hash.startsWith("#/blocking") && el.isConnected) rerender(); }, wait);
+}
+
+function pauseControls() {
+  const length = select([["5", "5 minutes"], ["15", "15 minutes"], ["60", "1 hour"], ["240", "4 hours"]], "15");
+  return h("div", { class: "actions" }, length, h("button", { title: "Answer every name normally for a while, to see whether blocking is what breaks something", onclick: () => pause(Number(length.value)) }, "Pause blocking"));
+}
+
+// pause pauses blocking for minutes, or resumes it (0). It applies at
+// once, also with a draft open: it's for trying something now.
+async function pause(minutes) {
+  try {
+    await api("POST", minutes ? "/blocking/pause" : "/blocking/resume", minutes ? { body: { minutes } } : {});
+    toast(minutes ? "Blocking paused" : "Blocking resumed");
+    rerender();
+  } catch (e) { toast(e.message, "err", 8000); }
+}
+
+// checkResult shows what blocking does with a name, and offers the way
+// to stop it: an allow rule (it beats every list, and a rule for a parent
+// domain), or, when your own block rule is for this very name, removing
+// that rule (a second rule for the same name isn't allowed).
+function checkResult(name, res, rules, writable) {
+  if (!res.length) return h("p", { class: "muted" }, "Blocking isn't used in any view yet: add a rule or a blocklist below.");
+  const n = name.trim().toLowerCase().replace(/\.$/, "");
+  const ruleById = new Map(rules.map((r) => [r.id, r]));
+  const blocked = res.filter((m) => m.result === "blocked");
+  const ownBlocks = [...new Set(blocked.map((m) => ruleById.get(m.rule_id)).filter((r) => r && r.name === n))];
+  const sameName = rules.filter((r) => r.name === n && !ownBlocks.includes(r));
+  let action = null;
+  if (writable && ownBlocks.length) {
+    action = h("p", null, h("button", { class: "small", onclick: () => removeRules(ownBlocks) }, "Remove your block rule for " + n),
+      h("span", { class: "muted small" }, ownBlocks.some((r) => !r.exact) ? " (it also covers the names below it)" : ""));
+  } else if (writable && blocked.length && !sameName.length) {
+    action = h("p", null, h("button", { class: "small", onclick: () => addRule(n, "allow", false, []) }, "Allow " + n),
+      h("span", { class: "muted small" }, " adds an allow rule for it and the names below it, which beats every list and any rule for a parent domain."));
+  } else if (writable && blocked.length) {
+    action = h("p", { class: "muted small" }, "There already is a rule for " + n + " (in other views): change it under Your rules.");
+  }
+  return h("div", null,
+    h("ul", { class: "plain" }, res.map((m) => {
+      const rule = ruleById.get(m.rule_id);
+      return h("li", null,
+        m.view ? h("span", { class: "muted" }, "view " + m.view + ": ") : null,
+        m.result === "blocked" ? badge("blocked", "err") : m.result === "allowed" ? badge("allowed", "ok") : badge("not blocked", ""),
+        " ",
+        m.list ? ["by blocklist ", h("strong", null, m.list), " (entry ", h("code", null, m.entry), ")"]
+          : m.result !== "none" ? ["by your rule to ", rule ? rule.action : "", " ", h("code", null, rule ? rule.name : m.entry.replace(/^\*\./, "")), rule && !rule.exact ? " and below" : ""] : null);
+    })),
+    action);
+}
+
+async function removeRules(list) {
+  try {
+    let r;
+    for (const rule of list) r = await change("DELETE", "/blocking/rules/" + rule.id);
+    toast(describeResult(r));
+    rerender();
+  } catch (e) { toast(e.message, "err", 8000); }
+}
+
+async function addRule(name, action, exact, views, comment) {
+  try {
+    const r = await change("POST", "/blocking/rules", { name, action, exact, views, comment: comment || "" });
+    toast(describeResult(r));
+    rerender();
+    return true;
+  } catch (e) { toast(e.message, "err", 8000); return false; }
+}
+
+// viewPicker is a compact choice of views: it shows the choice, and opens
+// a list of checkboxes (none ticked: every view that offers recursion).
+function viewPicker(views, autoViews, selected = []) {
+  if (!views.length) return { el: null, picker: null, value: () => [] };
+  const boxes = views.map((v) => checkbox(v.name, selected.includes(v.name)));
+  const value = () => views.filter((v, i) => boxes[i].input.checked).map((v) => v.name);
+  const summary = h("summary");
+  const show = () => {
+    const sel = value();
+    summary.textContent = sel.length ? sel.join(", ") : "automatic" + (autoViews && autoViews.length ? " (" + autoViews.join(", ") + ")" : "");
+  };
+  boxes.forEach((b) => b.input.addEventListener("change", show));
+  show();
+  const picker = h("details", { class: "view-picker" }, summary,
+    h("div", { class: "view-picker-list" }, h("div", { class: "muted small" }, "None ticked: every view that offers recursion"), boxes));
+  return { el: h("div", { class: "f" }, h("label", null, "Views"), picker), picker, value };
+}
+
+// The views a list or rule names itself ([] when automatic).
+const ownViews = (x) => (x.auto_views ? [] : x.views);
+
+// editDialog changes a list or rule: fields are [label, control, help]
+// rows, and data() the PATCH body.
+async function editDialog(title, path, rows, data) {
+  const err = h("div");
+  await modal(title, h("div", null, h("div", { class: "form-grid" }, rows.filter(Boolean).map(([l, c, help]) => field(l, c, help))), err), [
+    { label: "Cancel", value: null },
+    { label: "Save", kind: "primary", onclick: async () => {
+      try {
+        const r = await change("PATCH", path, data());
+        toast(describeResult(r));
+        rerender();
+        return true;
+      } catch (e) { mount(err, errorBox(e)); return false; }
+    } },
+  ], { sticky: true });
+}
+
+function editList(l, views, autoViews) {
+  const name = input({ value: l.name, class: "mono" });
+  const url = input({ value: l.url, class: "mono", style: { width: "100%" } });
+  const comment = input({ value: l.comment || "" });
+  const vp = viewPicker(views, autoViews, ownViews(l));
+  editDialog("Edit blocklist " + l.name, "/blocking/lists/" + l.id, [
+    ["Name", name], ["URL", url, "A new URL is downloaded right after saving."],
+    vp.picker ? ["Views", vp.picker, "None ticked: every view that offers recursion."] : null,
+    ["Comment", comment],
+  ], () => ({ name: name.value.trim(), url: url.value.trim(), views: vp.value(), comment: comment.value }));
+}
+
+function editRule(r, views, autoViews) {
+  const name = input({ value: r.name, class: "mono" });
+  const action = select([["block", "Block"], ["allow", "Allow"]], r.action);
+  const exact = checkbox("only this exact name", !!r.exact);
+  const comment = input({ value: r.comment || "" });
+  const vp = viewPicker(views, autoViews, ownViews(r));
+  editDialog("Edit the rule for " + r.name, "/blocking/rules/" + r.id, [
+    ["Action", action], ["Domain", name], ["", exact],
+    vp.picker ? ["Views", vp.picker, "None ticked: every view that offers recursion."] : null,
+    ["Comment", comment],
+  ], () => ({ name: name.value.trim(), action: action.value, exact: exact.input.checked, views: vp.value(), comment: comment.value }));
+}
+
+// An open view picker closes when you click elsewhere.
+document.addEventListener("click", (ev) => {
+  for (const d of document.querySelectorAll("details.view-picker[open]")) if (!d.contains(ev.target)) d.open = false;
+});
+
+function viewsCell(x) {
+  if (!x.views.length) return h("span", { class: "muted" }, "none");
+  return x.auto_views ? [x.views.join(", "), h("span", { class: "muted small" }, " (auto)")] : x.views.join(", ");
+}
+
+function rulesPanel(rules, views, autoViews, writable) {
+  const name = input({ placeholder: "ads.example.com", class: "mono" });
+  const action = select([["block", "Block"], ["allow", "Allow"]], "block");
+  const exact = checkbox("only this exact name", false);
+  const comment = input({ placeholder: "optional" });
+  const vp = viewPicker(views, autoViews);
+  const err = h("div");
+  const form = h("form", { class: "inline-form", onsubmit: async (ev) => {
+    ev.preventDefault();
+    try {
+      const r = await change("POST", "/blocking/rules", { name: name.value.trim(), action: action.value, exact: exact.input.checked, views: vp.value(), comment: comment.value });
+      toast(describeResult(r));
+      rerender();
+    } catch (e) { mount(err, errorBox(e)); }
+  } },
+    h("div", { class: "f" }, h("label", null, "Action"), action),
+    h("div", { class: "f grow" }, h("label", null, "Domain"), name),
+    h("div", { class: "f" }, h("label", null, " "), exact),
+    h("div", { class: "f" }, h("label", null, "Comment"), comment),
+    vp.el,
+    h("div", { class: "f" }, h("label", null, " "), h("button", { class: "primary", type: "submit" }, "Add rule")));
+  return h("div", { class: "panel" },
+    h("h2", null, "Your rules"),
+    h("p", { class: "muted small" }, "A rule covers the domain and every name below it, unless it's for the exact name only. Rules beat every blocklist, and the most specific rule wins: allowing cdn.example.com overrides blocking example.com for cdn.example.com and the names below it."),
+    writable ? [form, err] : null,
+    table([
+      { label: "Action", render: (r) => [r.action === "block" ? badge("block", "err") : badge("allow", "ok"), r.pending ? [" ", pendingBadge(r.pending)] : null] },
+      { label: "Domain", render: (r) => [h("span", { class: "mono" }, r.name), r.exact ? null : h("span", { class: "muted small" }, " and below")] },
+      views.length ? { label: "Views", render: viewsCell } : null,
+      { label: "Comment", render: (r) => h("span", { class: "muted" }, r.comment || "") },
+      writable ? { label: "", render: (r) => r.pending === "delete" ? "" : h("span", null,
+        h("button", { class: "small", onclick: () => editRule(r, views, autoViews) }, "Edit"), " ",
+        h("button", { class: "small danger", onclick: () => del("/blocking/rules/" + r.id, "the rule for " + r.name) }, "Delete")), tdClass: "actions-cell" } : null,
+    ].filter(Boolean), rules, { empty: "No rules yet.", rowClass: (r) => r.pending ? "pending-" + r.pending : "" }));
+}
+
+function listsPanel(lists, views, autoViews, writable) {
+  const name = input({ placeholder: "hagezi-multi", class: "mono", style: { width: "11em" } });
+  const url = input({ placeholder: "https://…", class: "mono" });
+  const vp = viewPicker(views, autoViews);
+  const err = h("div");
+  const form = h("form", { class: "inline-form", onsubmit: async (ev) => {
+    ev.preventDefault();
+    try {
+      const r = await change("POST", "/blocking/lists", { name: name.value.trim(), url: url.value.trim(), views: vp.value() });
+      toast(describeResult(r) + (r.applied ? " — jarld downloads it now" : ""));
+      rerender();
+    } catch (e) { mount(err, errorBox(e)); }
+  } },
+    h("div", { class: "f" }, h("label", null, "Name"), name),
+    h("div", { class: "f grow" }, h("label", null, "URL"), url),
+    vp.el,
+    h("div", { class: "f" }, h("label", null, " "), h("button", { class: "primary", type: "submit" }, "Add list")));
+  const used = new Set(lists.map((l) => l.url));
+  const picks = suggestions.filter(([, u]) => !used.has(u));
+  const totalMB = lists.reduce((a, l) => a + (l.memory_mb || 0), 0);
+  return h("div", { class: "panel" },
+    h("h2", null, "Blocklists"),
+    h("p", { class: "muted small" }, "jarld downloads each list, checks it for changes daily, and keeps using the previous version if an update fails. Hosts, plain domain and Adblock (||domain^) lists work; Adblock entries also cover the names below them."),
+    writable ? [form, err] : null,
+    writable && picks.length ? h("p", { class: "small" }, h("span", { class: "muted" }, "Well-known lists: "),
+      picks.map(([n, u, d], i) => [i ? " · " : "", h("a", { href: "#", title: d + "\n" + u, onclick: (ev) => { ev.preventDefault(); name.value = n; url.value = u; name.focus(); } }, n)])) : null,
+    table([
+      { label: "Name", render: (l) => [h("strong", { class: "mono" }, l.name), l.pending ? [" ", pendingBadge(l.pending)] : null] },
+      { label: "State", render: (l) => { const [t, k] = stateBadge[l.state] || [l.state, ""]; return [badge(t, k), l.status && l.status.error ? h("div", { class: "small err-text" }, l.status.error) : null]; } },
+      { label: "Domains", render: (l) => l.status && l.status.updated_at ? l.status.entries.toLocaleString() : "–", tdClass: "right" },
+      views.length ? { label: "Views", render: viewsCell } : null,
+      { label: "Updated", render: (l) => l.status && l.status.updated_at ? h("span", { title: "checked " + time(l.status.checked_at) }, relTime(l.status.updated_at)) : "–", tdClass: "small" },
+      { label: "Memory", render: (l) => l.memory_mb ? h("span", { title: "named's memory for this list, estimated (all its views)" }, "~" + l.memory_mb + " MB") : "–", tdClass: "small right" },
+      { label: "URL", render: (l) => h("a", { href: l.url, target: "_blank", rel: "noopener", class: "small mono", title: l.url }, shortURL(l.url)) },
+      writable ? { label: "", render: (l) => l.pending === "delete" ? "" : h("span", null,
+        h("button", { class: "small", onclick: () => editList(l, views, autoViews) }, "Edit"), " ",
+        h("button", { class: "small", disabled: l.state === "disabled" || !!l.pending, title: "Download it now (it is checked daily anyway)", onclick: () => refresh(l) }, "Refresh"), " ",
+        h("button", { class: "small", onclick: () => toggle(l) }, l.disabled ? "Enable" : "Disable"), " ",
+        h("button", { class: "small danger", onclick: () => del("/blocking/lists/" + l.id, "blocklist " + l.name) }, "Delete")), tdClass: "actions-cell" } : null,
+    ].filter(Boolean), lists, { empty: "No blocklists yet.", rowClass: (l) => l.pending ? "pending-" + l.pending : l.disabled ? "disabled" : "" }),
+    totalMB ? h("p", { class: "muted small" }, "named needs about " + totalMB + " MB of memory for these lists (an estimate). A list costs memory in every view it applies to, so pick views if some don't need it.") : null);
+}
+
+function shortURL(u) {
+  const s = u.replace(/^https?:\/\//, "");
+  return s.length > 48 ? s.slice(0, 22) + "…" + s.slice(-24) : s;
+}
+
+async function refresh(l) {
+  toast("Downloading " + l.name + "…", "ok", 2000);
+  try {
+    const r = await api("POST", "/blocking/lists/" + l.id + "/refresh");
+    if (r.status && r.status.error) toast(l.name + ": " + r.status.error, "err", 10000);
+    else toast(l.name + ": " + r.status.entries.toLocaleString() + " domains");
+    rerender();
+  } catch (e) { toast(e.message, "err", 8000); }
+}
+
+async function toggle(l) {
+  try {
+    const r = await change("PATCH", "/blocking/lists/" + l.id, { disabled: !l.disabled });
+    toast(describeResult(r));
+    rerender();
+  } catch (e) { toast(e.message, "err", 8000); }
+}
+
+async function del(path, what) {
+  if (!(await confirmDialog("Delete", "Delete " + what + "?", "Delete", "danger"))) return;
+  try {
+    const r = await change("DELETE", path);
+    toast(describeResult(r));
+    rerender();
+  } catch (e) { toast(e.message, "err", 8000); }
+}
+

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

@@ -1,4 +1,4 @@
-import { h, mount, time, relTime, problemsList, badge, plural } from "../ui.js";
+import { h, mount, time, fmtTime, relTime, problemsList, badge, plural } from "../ui.js";
 import { get, state } from "../api.js";
 
 export async function render(el) {
@@ -40,6 +40,16 @@ export async function render(el) {
       h("strong", null, "The last backup failed "), time(b.last_error_at), ": " + b.last_error,
       h("div", { class: "small" }, "See 'journalctl -u jarl-backup' on the server.")));
   }
+  if (st.blocking_paused_until) {
+    parts.push(h("div", { class: "msg info" },
+      h("strong", null, "Blocking is paused until " + fmtTime(st.blocking_paused_until) + "."), " It resumes by itself. ", h("a", { href: "#/blocking" }, "Blocking")));
+  }
+  for (const e of st.blocklist_errors || []) {
+    parts.push(h("div", { class: "msg warn" },
+      h("strong", null, "Blocklist " + e.name + " couldn't be updated: "), e.error + ". ",
+      e.updated_at ? ["named keeps using the version from ", time(e.updated_at), ". "] : "It isn't in use yet. ",
+      "jarld tries again within the hour. ", h("a", { href: "#/blocking" }, "Blocking")));
+  }
   const tf = st.totp;
   if (tf && tf.missing && tf.missing.length) {
     parts.push(h("div", { class: "msg warn" },

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

@@ -1,5 +1,5 @@
 import { h, mount, table, field, input, select, textarea, toast, errorBox, badge, confirmDialog, lines } from "../ui.js";
-import { get, change, describeResult } from "../api.js";
+import { get, change, describeResult, draftQuery } from "../api.js";
 import { rerender } from "../app.js";
 import { emailOf } from "./zones.js";
 import { amlContext, suggestions } from "../aml.js";
@@ -28,7 +28,7 @@ function valueWidget(stmt, value, ctx) {
     return { el: h("div", null, t, ctx ? suggestions(t, ctx) : null), get: () => "{ " + lines(t.value).map((l) => l.replace(/;$/, "") + ";").join(" ") + " }", hint: "One element per line: address or prefix, !negated, key NAME, ACL name, any, none, localhost, localnets. First match wins." };
   }
   if (kind === "raw") {
-    const t = textarea(value || "", { class: "mono", rows: 3 });
+    const t = codeArea(value || "");
     // Statements such as allow-transfer and listen-on take an address
     // match list after optional parameters: suggest names at the cursor.
     const takesList = stmt && /address_match_element/.test(stmt.grammar || "");
@@ -39,9 +39,42 @@ function valueWidget(stmt, value, ctx) {
   return { el: i, get: () => i.value.trim() };
 }
 
+// codeArea is a textarea for named.conf text: as tall as its content
+// (up to 30 lines), Tab indents, Enter keeps the line's indentation. After
+// Esc, Tab moves on to the next field again.
+function codeArea(value) {
+  const t = textarea(value, { class: "mono code", spellcheck: "false" });
+  const fit = () => { t.rows = Math.min(30, Math.max(3, t.value.split("\n").length + 1)); };
+  fit();
+  let tabMoves = false;
+  const insert = (text) => {
+    const { selectionStart: a, selectionEnd: b } = t;
+    t.setRangeText(text, a, b, "end");
+    fit();
+  };
+  t.addEventListener("input", fit);
+  t.addEventListener("focus", () => { tabMoves = false; });
+  t.addEventListener("keydown", (ev) => {
+    if (ev.key === "Escape") { tabMoves = true; return; }
+    if (ev.key === "Tab" && !tabMoves && !ev.shiftKey) {
+      ev.preventDefault();
+      insert("\t");
+    } else if (ev.key === "Enter" && !ev.shiftKey && !ev.ctrlKey && !ev.metaKey) {
+      const line = t.value.slice(0, t.selectionStart).split("\n").pop();
+      let indent = line.match(/^\t*/)[0];
+      if (line.trimEnd().endsWith("{")) indent += "\t";
+      ev.preventDefault();
+      insert("\n" + indent);
+    }
+  });
+  return t;
+}
+
 // optionsEditor renders the options of one scope.
 export async function optionsEditor(el, { scope, scope_id, catalogScope, title, intro }) {
-  const [opts, cat, ctx] = await Promise.all([get("/options", { scope, scope_id }), catalog(catalogScope), amlContext()]);
+  // With a draft open, show the options as they will be: a staged edit
+  // stays visible after Save.
+  const [opts, cat, ctx] = await Promise.all([get("/options", draftQuery({ scope, scope_id })), catalog(catalogScope), amlContext()]);
   const byName = Object.fromEntries(cat.map((s) => [s.name, s]));
   const err = h("div");
   const listEl = h("div");
@@ -49,7 +82,7 @@ export async function optionsEditor(el, { scope, scope_id, catalogScope, title,
   const draw = () => {
     mount(listEl, table([
       { label: "Option", render: (o) => h("span", null, h("strong", { class: "mono" }, o.name), o.status ? [" ", badge(o.status, "warn")] : null), tdClass: "nowrap" },
-      { label: "Value", render: (o) => editing === o.id ? editRow(o) : h("pre", { style: { padding: "2px 6px", whiteSpace: "pre-wrap" } }, o.value || "(no value)") },
+      { label: "Value", render: (o) => editing === o.id ? editRow(o) : h("pre", { class: "code", style: { padding: "2px 6px", whiteSpace: "pre-wrap" } }, o.formatted || o.value || "(no value)") },
       { label: "Description", render: (o) => h("span", { class: "muted small" }, o.description || ""), tdClass: "small" },
       { label: "", render: (o) => editing === o.id ? "" : h("span", null,
         h("button", { class: "small", onclick: () => { editing = o.id; draw(); } }, "Edit"), " ",
@@ -57,7 +90,7 @@ export async function optionsEditor(el, { scope, scope_id, catalogScope, title,
     ], opts, { empty: "No options set; BIND's defaults apply." }));
   };
   const editRow = (o) => {
-    const w = valueWidget(byName[o.name], o.value, ctx);
+    const w = valueWidget(byName[o.name], o.formatted || o.value, ctx);
     const e2 = h("div");
     return h("div", null, w.el, w.hint ? h("div", { class: "hint" }, w.hint) : null,
       h("div", { class: "actions", style: { marginTop: "6px" } },

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

@@ -56,13 +56,18 @@ export async function render(el, params, query) {
     tile("Per second", s.avg_qps < 10 ? s.avg_qps.toFixed(2) : Math.round(s.avg_qps).toLocaleString(), "on average"),
     s.peak ? tile("Busiest " + s.peak.per, compact(s.peak.queries), fmtTime(s.peak.time)) : null,
     s.nxdomain_ratio != null ? tile("NXDOMAIN", pct(s.nxdomain_ratio), "of queries named no existing name") : null,
-    s.cache_hit_ratio != null ? tile("Cache hits", pct(s.cache_hit_ratio), "of recursive queries answered from cache") : null));
+    s.cache_hit_ratio != null ? tile("Cache hits", pct(s.cache_hit_ratio), "of recursive queries answered from cache") : null,
+    s.blocked_ratio != null ? tile("Blocked", pct(s.blocked_ratio), compact(s.blocked) + " queries, by your rules and blocklists") : null));
 
   // Volume over time: one series, so no legend box; the title names it.
+  // With blocking, a second line shows how many of them were blocked.
   const q = timeline.series.find((x) => x.key === "queries") || { values: timeline.times.map(() => 0) };
   const qSeries = [{ label: "Queries", values: q.values, slot: 1 }];
-  parts.push(chartCard("Queries", "per " + stepName(timeline.step) + ", " + rangeLabel,
-    lineChart({ series: qSeries, times: timeline.times, step, area: true }), timeTable(qSeries, timeline.times, step), { wide: true }));
+  const bl = timeline.series.find((x) => x.key === "blocked");
+  if (bl && bl.values.some((v) => v > 0)) qSeries.push({ label: "Blocked", values: bl.values, slot: 2 });
+  parts.push(chartCard(qSeries.length > 1 ? "Queries and blocked queries" : "Queries", "per " + stepName(timeline.step) + ", " + rangeLabel,
+    lineChart({ series: qSeries, times: timeline.times, step, area: true }), timeTable(qSeries, timeline.times, step),
+    { wide: true, legend: qSeries.length > 1 ? legend(qSeries) : null }));
 
   // Failed answers: three fixed series, legend plus end labels.
   const fSeries = failures.map((f) => ({ ...f, values: (errors.series.find((x) => x.key === f.key) || { values: errors.times.map(() => 0) }).values }));
@@ -84,7 +89,9 @@ export async function render(el, params, query) {
       listCard("Busiest clients", "", barList(t.client)),
       listCard("Names that don't exist", "NXDOMAIN answers: typos, removed hosts, misconfigured clients, malware", barList(t.nxdomain, { empty: "None " + rangeLabel + "." })),
       listCard("Refused clients", "clients asking for something they may not have (often internet scanners)", barList(t.refused, { empty: "None " + rangeLabel + "." })),
-      t.servfail.length ? listCard("Names that failed to resolve", "SERVFAIL answers", barList(t.servfail)) : null));
+      t.servfail.length ? listCard("Names that failed to resolve", "SERVFAIL answers", barList(t.servfail)) : null,
+      t.blocked_client.length ? listCard("Clients with the most blocked queries", "often a smart TV, phone or app phoning home", barList(t.blocked_client)) : null,
+      t.blocked.length ? listCard("Most blocked names", "answered \"doesn't exist\" by blocking; click a name to see why, or to allow it", barList(t.blocked, { href: (k) => "#/blocking?check=" + encodeURIComponent(k) })) : null));
   } else {
     parts.push(h("div", { class: "msg info" }, "Top names and clients need the response log: set stats.query_log: true in /etc/jarl/jarl.yaml and restart jarl."));
   }
@@ -98,7 +105,8 @@ export async function render(el, params, query) {
     b.view.length > 1 || (b.view.length === 1 && b.view[0].key !== "_default") ? listCard("Views", "", barList(b.view, { label: viewLabel })) : null,
     b.zone.length ? listCard("Zones", "queries per local zone; other = names in no local zone (recursion)", barList(b.zone, { label: (k) => (k === "-" ? "other" : k), href: (k) => (k === "-" ? null : "#/search?q=" + encodeURIComponent(k)) })) : null,
     b.answer.length ? listCard("Answers", "authoritative (your zones) or recursive (from the cache or the internet)", barList(b.answer)) : null,
-    rtt.length ? listCard("Upstream response time", "how long other servers took to answer named's recursive queries", barList(rtt)) : null));
+    rtt.length ? listCard("Upstream response time", "how long other servers took to answer named's recursive queries", barList(rtt)) : null,
+    b.blocklist.length ? listCard("Blocked by", "which of your rules and blocklists blocked queries", barList(b.blocklist, { label: (k) => (k === "rules" ? "your rules" : k), href: () => "#/blocking" })) : null));
   el.classList.remove("refreshing");
   mount(el, parts);
   scheduleRefresh(el, params, query, gen);
@@ -107,14 +115,14 @@ export async function render(el, params, query) {
 async function loadAll(since, heatSince, queryLog) {
   const p = {
     summary: get("/stats/summary", { since, top: 0 }),
-    timeline: get("/stats/timeline", { since, key: "queries" }),
+    timeline: get("/stats/timeline", { since, key: "queries,blocked" }),
     errors: get("/stats/timeline", { since, key: failures.map((f) => f.key).join(",") }),
     heat: get("/stats/heatmap", { since: heatSince }),
   };
-  const groups = ["qtype", "rcode", "view", "zone", "answer", "rtt"];
+  const groups = ["qtype", "rcode", "view", "zone", "answer", "rtt", "blocklist"];
   groups.forEach((g) => { p["b_" + g] = get("/stats/breakdown", { group: g, since }); });
   if (queryLog) {
-    for (const k of ["name", "client", "nxdomain", "refused", "servfail"]) p["t_" + k] = get("/stats/top", { kind: k, since, limit: 15 });
+    for (const k of ["name", "client", "nxdomain", "refused", "servfail", "blocked", "blocked_client"]) p["t_" + k] = get("/stats/top", { kind: k, since, limit: 15 });
   }
   const keys = Object.keys(p);
   const vals = await Promise.all(Object.values(p));

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

@@ -453,11 +453,12 @@ async function recordsTab(el, zone, query) {
     const rows = current.filter((r) => (!q || r.name.includes(q) || r.data.toLowerCase().includes(q) || (r.comment || "").toLowerCase().includes(q)) && (!typeFilter.value || r.type === typeFilter.value) &&
       (!stateFilter.value || !!r.disabled === (stateFilter.value === "off")));
     mount(list, table([
-      { label: "Name", render: (r) => reverse && addressOf(r.name) ? [r.relative_name, " ", h("span", { class: "muted small" }, addressOf(r.name))] : r.relative_name, tdClass: "name" },
+      { label: "Name", render: (r) => [reverse && addressOf(r.name) ? [r.relative_name, " ", h("span", { class: "muted small" }, addressOf(r.name))] : r.relative_name,
+        r.disabled && r.pending !== "disable" ? [" ", badge("disabled", "off")] : null], tdClass: "name" },
       { label: "TTL", render: (r) => r.ttl !== undefined && r.ttl !== null ? String(r.ttl) : h("span", { class: "muted", title: "zone default" }, String(r.effective_ttl)), tdClass: "mono" },
       { label: "Type", render: (r) => h("strong", null, r.type) },
       { label: "Data", render: (r) => r.data, tdClass: "data" },
-      { label: "Comment", render: (r) => [r.disabled && r.pending !== "disable" ? [badge("disabled"), " "] : null, r.pending ? [pendingBadge(r.pending), " "] : null, h("span", { class: "muted" }, r.comment || "")] },
+      { label: "Comment", render: (r) => [r.pending ? [pendingBadge(r.pending), " "] : null, h("span", { class: "muted" }, r.comment || "")] },
       { label: "", render: (r) => r.pending === "delete" ? "" : h("span", null,
         h("button", { class: "small", title: "Edit", onclick: () => edit(r) }, "Edit"), " ",
         r.disabled

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

@@ -23,7 +23,7 @@ export async function render(el, params, query) {
     lastList.zones = hash;
     const rows = zones.filter((z) => (!q || z.name.includes(q)) && (!viewSel.value || z.view === viewSel.value) && (!typeSel.value || z.type === typeSel.value));
     mount(list, table([
-      { label: "Zone", render: (z) => [z.pending === "delete" ? h("span", null, z.display_name) : h("a", { href: "#/zones/" + z.id }, z.display_name), z.pending ? [" ", pendingBadge(z.pending)] : null], tdClass: "name" },
+      { label: "Zone", render: (z) => [z.pending === "delete" ? h("span", null, z.display_name) : h("a", { href: "#/zones/" + z.id }, z.display_name), dnssecLock(z), z.pending ? [" ", pendingBadge(z.pending)] : null], tdClass: "name" },
       views.length ? { label: "View", render: (z) => viewLink(viewsById.get(z.view_id), z.view, hash) } : null,
       { label: "Type", render: (z) => badge(z.type, z.type === "primary" ? "accent" : "") },
       { label: "Records", render: (z) => z.type === "primary" ? [String(z.record_count), z.disabled_count ? h("span", { class: "muted small", title: z.disabled_count + " disabled (left out of the zone)" }, " (" + z.disabled_count + " off)") : null] : "", class: "right", tdClass: "right" },
@@ -236,6 +236,24 @@ export function emailOf(rname) {
   return m[1].replace(/\\\./g, ".") + "@" + m[2];
 }
 
+// dnssecLock marks a signed zone with a padlock linking to its DNSSEC tab:
+// closed while signed, open while signing is being turned off (BIND's
+// insecure policy).
+function dnssecLock(z) {
+  if (!z.dnssec_policy) return null;
+  const off = z.dnssec_policy === "insecure";
+  const a = h("a", {
+    class: "dnssec-lock" + (off ? " off" : ""),
+    href: "#/zones/" + z.id + "/dnssec",
+    title: off ? "DNSSEC: signing is being turned off" : "DNSSEC: signed (policy " + z.dnssec_policy + ")",
+    "aria-label": off ? "DNSSEC being turned off" : "DNSSEC signed",
+  });
+  a.innerHTML = '<svg viewBox="0 0 16 16" width="13" height="13" aria-hidden="true"><path d="' +
+    (off ? "M5 7V5a3 3 0 0 1 5.8-1.1" : "M5 7V5a3 3 0 0 1 6 0v2") +
+    '" fill="none" stroke="currentColor" stroke-width="1.6" stroke-linecap="round"/><rect x="3" y="7" width="10" height="7.5" rx="1.5" fill="currentColor"/></svg>';
+  return a;
+}
+
 export function pendingBadge(kind) {
   return badge({ add: "pending: new", change: "pending: changed", delete: "pending: delete", disable: "pending: disable", enable: "pending: enable" }[kind] || kind, kind === "delete" ? "err" : "warn");
 }

internal/web/static/assets/style.css

@@ -4,6 +4,7 @@
   --panel: #ffffff;
   --text: #1d2330;
   --muted: #5f6b7d;
+  --hatch: rgba(95, 107, 125, 0.13);
   --border: #d9dee6;
   --accent: #2f5fb3;
   --accent-text: #ffffff;
@@ -34,6 +35,7 @@
     --panel: #1c2027;
     --text: #e3e7ee;
     --muted: #9aa5b5;
+    --hatch: rgba(154, 165, 181, 0.12);
     --border: #2f3540;
     --accent: #6d9be8;
     --accent-text: #0f1520;
@@ -58,7 +60,7 @@
   }
 }
 :root[data-theme="dark"] {
-  --bg: #14171c; --panel: #1c2027; --text: #e3e7ee; --muted: #9aa5b5; --border: #2f3540;
+  --bg: #14171c; --panel: #1c2027; --text: #e3e7ee; --muted: #9aa5b5; --border: #2f3540; --hatch: rgba(154, 165, 181, 0.12);
   --accent: #6d9be8; --accent-text: #0f1520; --accent-soft: #23314a; --ok: #59c287; --ok-soft: #173326;
   --warn: #e5b450; --warn-soft: #3a2f15; --err: #f08077; --err-soft: #3c1f1d; --info-soft: #232833;
   --code-bg: #242933; --add: #183a25; --add-text: #9fe3b5; --del: #43201e; --del-text: #f7b2ac; --hunk: #23314a;
@@ -114,6 +116,7 @@ main { padding: 16px; max-width: 1400px; margin: 0 auto; }
   padding: 8px 16px;
 }
 .pending-bar strong { color: var(--warn); }
+.pending-bar .apply-now { margin-left: auto; }
 /* The review/live switch in the header. */
 .mode-toggle { display: inline-flex; align-items: center; gap: 6px; padding: 3px 10px; border-radius: 999px; font-size: 12px; font-weight: 500; background: transparent; color: var(--muted); border: 1px solid var(--border); }
 .mode-toggle:hover { color: var(--text); border-color: var(--accent); }
@@ -141,6 +144,8 @@ th { font-size: 12px; color: var(--muted); font-weight: 600; text-transform: upp
 tr:hover td { background: var(--info-soft); }
 td.data { font-family: var(--mono); font-size: 13px; word-break: break-all; }
 td.name { font-family: var(--mono); font-size: 13px; white-space: nowrap; }
+a.dnssec-lock { display: inline-flex; vertical-align: -1px; margin-left: 6px; color: var(--ok); text-decoration: none; }
+a.dnssec-lock.off { color: var(--warn); }
 tr.same-name-next td { border-bottom-color: color-mix(in srgb, var(--border) 40%, transparent); }
 td.actions-cell { white-space: nowrap; text-align: right; width: 1%; }
 tr.editing td { background: var(--accent-soft); }
@@ -148,6 +153,9 @@ tr.pending-add td { background: var(--add); }
 tr.pending-change td, tr.pending-disable td, tr.pending-enable td { background: var(--warn-soft); }
 tr.pending-delete td { background: var(--del); text-decoration: line-through; color: var(--muted); }
 tr.disabled td:not(.actions-cell), tr.disabled td strong { color: var(--muted); }
+/* Disabled records: hatched, so they stand out from live and pending rows. */
+tr.disabled td { background-image: repeating-linear-gradient(135deg, transparent 0 7px, var(--hatch) 7px 9px); }
+.badge.off { background: var(--muted); color: var(--panel); }
 button.toggle { min-width: 5.2em; }
 .empty { color: var(--muted); padding: 18px; text-align: center; }
 
@@ -164,9 +172,10 @@ textarea { width: 100%; min-height: 80px; resize: vertical; }
 .form-grid > label { padding-top: 6px; color: var(--muted); }
 .form-grid .help { grid-column: 2; margin-top: -4px; color: var(--muted); font-size: 12px; }
 .form-grid input, .form-grid select { width: 100%; max-width: 560px; }
+.form-grid input[type=checkbox] { width: auto; }
 .inline-form { display: flex; gap: 6px; flex-wrap: wrap; align-items: flex-end; }
 .inline-form .f { display: flex; flex-direction: column; gap: 2px; }
-.inline-form .f label { font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.3px; }
+.inline-form .f label:not(.check) { font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.3px; }
 .inline-form .grow { flex: 1; min-width: 220px; }
 .inline-form .grow input { width: 100%; }
 .hint { color: var(--muted); font-size: 12px; margin-top: 4px; }
@@ -440,4 +449,11 @@ footer.site a:hover { color: var(--accent); text-decoration-color: currentColor;
 .query-log code { background: var(--code-bg); padding: 1px 6px; border-radius: 4px; overflow-wrap: anywhere; }
 .query-log li.pending code { opacity: 0.85; }
 .err-text { color: var(--err); }
+ul.plain { list-style: none; margin: 8px 0; padding: 0; }
+.code { tab-size: 4; }
+textarea.code { width: 100%; white-space: pre; overflow-wrap: normal; overflow-x: auto; }
+details.view-picker { position: relative; }
+details.view-picker summary { cursor: pointer; padding: 5px 8px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--panel); min-width: 12em; max-width: 24em; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+details.view-picker[open] .view-picker-list { position: absolute; z-index: 20; top: calc(100% + 4px); left: 0; min-width: 14em; max-height: 260px; overflow-y: auto; display: flex; flex-direction: column; gap: 4px; padding: 8px 10px; background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); }
+ul.plain li { padding: 3px 0; }
 .query-details { margin: 8px 0; }

scripts/e2e.sh

@@ -13,7 +13,7 @@ set -u
 ROOT=$(cd "$(dirname "$0")/.." && pwd)
 WORK=${WORK:-$(mktemp -d /tmp/jarl-e2e.XXXXXX)}
 E=$WORK
-DNS=${DNS_PORT:-25353}; CTL=${CTL_PORT:-25953}; HTTP=${HTTP_PORT:-28053}
+DNS=${DNS_PORT:-25353}; CTL=${CTL_PORT:-25953}; HTTP=${HTTP_PORT:-28053}; LISTS=${LISTS_PORT:-28054}
 if [ -n "${JARL_BIND_ROOT:-}" ]; then
 	B=$JARL_BIND_ROOT
 	export LD_LIBRARY_PATH=$(echo $B/usr/lib/*-linux-gnu | cut -d' ' -f1)
@@ -30,8 +30,9 @@ done
 mkdir -p $E/legacy $E/cache $E/data
 JARLD=$E/jarld J=$E/jarl
 (cd "$ROOT" && go build -o $JARLD ./cmd/jarld && go build -o $J ./cmd/jarl) || exit 1
-NAMED_PID= JARLD_PID=
+NAMED_PID= JARLD_PID= LISTS_PID=
 cleanup() {
+	[ -n "$LISTS_PID" ] && kill $LISTS_PID 2>/dev/null
 	if [ "${KEEP:-}" = 1 ]; then echo "left running in $WORK (named $NAMED_PID, jarld $JARLD_PID)"; return; fi
 	[ -n "$JARLD_PID" ] && kill $JARLD_PID 2>/dev/null
 	[ -n "$NAMED_PID" ] && kill $NAMED_PID 2>/dev/null
@@ -409,6 +410,68 @@ run "wipe the child" 0 $J zone dnssec wipe sub.adbraun.test --view external --ye
 run "delete the child" 0 $J zone delete sub.adbraun.test --view external --yes
 run "remove the delegation" 0 $J record delete adbraun.test sub NS --view external --yes
 
+# Blocking (docs/blocking.md). It only changes answers to recursive
+# queries, so these ask with recursion and look at which policy zone (if
+# any) the answer came from.
+rpz() {
+	$DIG +tries=1 +time=3 -p $DNS @127.0.0.1 "$1" A | awk '$4 == "SOA" && $1 ~ /jarl\.invalid\.$/ {print $1; f = 1} END {if (!f) print "none"}'
+}
+expect_rpz() { # DESC NAME WANT: named reloads in the background, so wait a little
+	local got
+	for i in $(seq 30); do got=$(rpz "$2"); [ "$got" = "$3" ] && break; sleep 0.2; done
+	if [ "$got" = "$3" ]; then ok "$1: $2 -> $3"; else bad "$1: $2 -> $got, want $3"; fi
+}
+mkdir -p $E/lists
+printf '# test list\n||tracker.adbraun.test^\n0.0.0.0 ads.adbraun.test\nnot a domain\n' > $E/lists/list.txt
+(cd $E/lists && exec python3 -m http.server --bind 127.0.0.1 $LISTS) > /dev/null 2>&1 &
+LISTS_PID=$!
+run "block add" 0 $J block add blocked.adbraun.test
+expect_rpz "a rule blocks the name" blocked.adbraun.test rules.jarl.invalid.
+expect_rpz "and the names below it" a.blocked.adbraun.test rules.jarl.invalid.
+expect_rpz "other names are answered" www.adbraun.test none
+run "named.conf has the policy" 0 grep -q 'response-policy' $E/etc-jarl/named.conf
+for i in $(seq 25); do curl -s -o /dev/null http://127.0.0.1:$LISTS/list.txt && break; sleep 0.2; done
+run "blocklist add" 0 $J blocklist add test http://127.0.0.1:$LISTS/list.txt
+run "blocklist refresh" 0 $J blocklist refresh test
+contains "test: 2 domains (1 lines skipped)"
+expect_rpz "an Adblock entry blocks the names below it" x.tracker.adbraun.test test.blocklist.jarl.invalid.
+expect_rpz "a hosts entry blocks the name" ads.adbraun.test test.blocklist.jarl.invalid.
+expect_rpz "but not the names below it" sub.ads.adbraun.test none
+run "blocklist list" 0 $J blocklist list
+contains "^test  *ok  *2 "
+run "block allow" 0 $J block allow ok.tracker.adbraun.test
+expect_rpz "an allow rule beats the list" deep.ok.tracker.adbraun.test none
+expect_rpz "the rest of the list still blocks" x.tracker.adbraun.test test.blocklist.jarl.invalid.
+run "block check" 0 $J block check deep.ok.tracker.adbraun.test
+contains "allowed by your rule"
+run "block pause" 0 $J block pause 5m
+expect_rpz "paused: a listed name is answered" x.tracker.adbraun.test none
+expect_rpz "paused: so is a blocked rule's name" blocked.adbraun.test none
+run "block list says it's paused" 0 $J block list
+contains "Blocking is paused until"
+run "block resume" 0 $J block resume
+expect_rpz "resumed: the list blocks again" x.tracker.adbraun.test test.blocklist.jarl.invalid.
+expect_rpz "resumed: the rule blocks again" blocked.adbraun.test rules.jarl.invalid.
+# The test server dates the file to the second, and the download above
+# remembers that date: change it a second later, as a real list would.
+sleep 1.1
+printf '||new.adbraun.test^\n' > $E/lists/list.txt
+run "blocklist refresh after the list changed" 0 $J blocklist refresh test
+expect_rpz "the new version applies" x.new.adbraun.test test.blocklist.jarl.invalid.
+expect_rpz "and replaces the old one" x.tracker.adbraun.test none
+printf '<html>gone</html>\n' > $E/lists/list.txt
+run "a broken download fails (exit 2)" 2 $J blocklist refresh test --force
+contains "no domains found"
+expect_rpz "and the previous version stays" x.new.adbraun.test test.blocklist.jarl.invalid.
+run "blocklist disable" 0 $J blocklist disable test
+expect_rpz "a disabled list doesn't block" x.new.adbraun.test none
+run "blocklist delete" 0 $J blocklist delete test --yes
+run "block delete" 0 $J block delete blocked.adbraun.test
+expect_rpz "a deleted rule doesn't block" blocked.adbraun.test none
+run "block delete (allow rule)" 0 $J block delete ok.tracker.adbraun.test
+run "no blocking left in named.conf" 1 grep -q 'response-policy' $E/etc-jarl/named.conf
+kill $LISTS_PID 2>/dev/null; LISTS_PID=
+
 run "status at the end" 0 $J status
 contains "Drift:.*none"