Address ranges in address match lists (IPv4 and IPv6)

ACLs, views' match lists, options with address match lists and blocking
client groups take ranges such as 10.0.10.101-10.0.10.199 or
2001:db8::100-2001:db8::1ff (negated, or with spaces around the dash, too).
Jarl stores the range as written and writes the fewest prefixes that cover
exactly that range to named.conf, with the range as a comment. New package
internal/iprange; namedconf gets an AMRange element (a range used to parse
as an ACL name), ExpandRanges and statement comments. Mistakes are refused
when entered, validation sees what ranges cover, and IPv6 ranges in the
IPv4-mapped space get a warning. The web UI shows what a range becomes
while typing (GET /catalog/ranges).

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

internal/catalog/catalog.go

@@ -493,6 +493,13 @@ func spaceElements(fields []string) []string {
 				f += " " + fields[i+1]
 				i++
 			}
+		case "-":
+			// A range with spaces around the dash: 10.0.0.1 - 10.0.0.9.
+			if len(out) > 0 && i+1 < len(fields) {
+				out[len(out)-1] += " - " + fields[i+1]
+				i++
+				continue
+			}
 		case "port", "tls":
 			if len(out) > 0 && i+1 < len(fields) {
 				out[len(out)-1] += " " + f + " " + fields[i+1]

internal/engine/clientgroups.go

@@ -5,6 +5,7 @@ import (
 	"net/netip"
 	"strings"
 
+	"jarl/internal/iprange"
 	"jarl/internal/model"
 )
 
@@ -52,10 +53,16 @@ func NormalizeMember(st *model.State, m string) (string, error) {
 	if p, err := netip.ParsePrefix(m); err == nil {
 		return p.Masked().String(), nil
 	}
+	if r, ok, err := iprange.Parse(m); ok {
+		if err != nil {
+			return "", errf(KindBadRequest, "%v", err)
+		}
+		return r.String(), nil
+	}
 	if a := st.ACLByName(m); a != nil {
 		return a.Name, nil
 	}
-	return "", errf(KindBadRequest, "%q is not an address, a prefix (10.10.0.0/24) or an ACL", m)
+	return "", errf(KindBadRequest, "%q is not an address, a prefix (10.10.0.0/24), a range (10.10.0.20-10.10.0.49) or an ACL", m)
 }
 
 func applyBlockStepPut(st *model.State, op model.Op, c *applyCtx) error {

internal/engine/ops.go

@@ -11,6 +11,7 @@ import (
 	"jarl/internal/auth"
 	"jarl/internal/catalog"
 	"jarl/internal/dnsname"
+	"jarl/internal/iprange"
 	"jarl/internal/model"
 	"jarl/internal/namedconf"
 	"jarl/internal/rr"
@@ -1144,9 +1145,44 @@ func NormalizeOption(st *model.State, scope string, scopeID int64, name, value s
 	if err != nil {
 		return "", "", errf(KindBadRequest, "option %s: %v", n, err)
 	}
+	namedconf.JoinRanges(parsed)
+	if err := checkOptionRanges(parsed, strings.Contains(stmt.Grammar, "<address_match_element>")); err != nil {
+		return "", "", errf(KindBadRequest, "option %s: %v", n, err)
+	}
 	return n, namedconf.Compact(parsed.Items[1:]), nil
 }
 
+// checkOptionRanges checks the address ranges in an option's blocks: they
+// must be valid, and only options with address match lists take them.
+func checkOptionRanges(st *namedconf.Stmt, aml bool) error {
+	for _, it := range st.Items {
+		if it.Block == nil {
+			continue
+		}
+		for _, s := range it.Block.Stmts {
+			items := s.Items
+			if len(items) == 2 && items[0].Bang {
+				items = items[1:]
+			}
+			if len(items) == 1 && items[0].Value != nil && !items[0].Value.Quoted {
+				if _, ok, err := iprange.Parse(items[0].Value.Text); ok {
+					if err != nil {
+						return err
+					}
+					if !aml {
+						return fmt.Errorf("%s: address ranges only work in address match lists (such as allow-query or an ACL), not here", items[0].Value.Text)
+					}
+					continue
+				}
+			}
+			if err := checkOptionRanges(s, aml); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 func applyOptionPut(st *model.State, op model.Op, c *applyCtx) error {
 	var in OptionInput
 	if err := decode(op.Data, &in); err != nil {

internal/engine/ranges_test.go

@@ -0,0 +1,113 @@
+package engine
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"jarl/internal/model"
+	"jarl/internal/validate"
+)
+
+func hasProblem(ps []validate.Problem, code string) bool {
+	for _, p := range ps {
+		if p.Code == code {
+			return true
+		}
+	}
+	return false
+}
+
+func describeProblems(e *Error) string {
+	var out []string
+	for _, p := range e.Problems {
+		out = append(out, p.Message)
+	}
+	return strings.Join(out, "; ")
+}
+
+func optionReq(name, value string) Request {
+	return NewRequest(OpOptionCreate, 0, OptionInput{Scope: model.Ptr(model.ScopeOptions), Name: &name, Value: &value})
+}
+
+func TestAddressRanges(t *testing.T) {
+	env := newEnv(t)
+	setupZone(env)
+	env.submit(env.admin,
+		NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("dhcp"), Elements: &[]string{"!10.0.10.150 - 10.0.10.160", "10.0.10.101-10.0.10.199", "2001:db8::100-2001:db8::1ff"}}),
+		optionReq("allow-query", "10.0.20.1 - 10.0.20.6; localhost"),
+	)
+	st := env.state()
+	if a := st.ACLByName("dhcp"); strings.Join(a.Elements, " ") != "!10.0.10.150-10.0.10.160 10.0.10.101-10.0.10.199 2001:db8::100-2001:db8::1ff" {
+		t.Errorf("stored elements = %q", a.Elements)
+	}
+	if o := st.FindOption(model.ScopeOptions, 0, "allow-query"); o == nil || o.Value != "{ 10.0.20.1-10.0.20.6; localhost; }" {
+		t.Errorf("stored option = %+v", o)
+	}
+	conf, _ := os.ReadFile(filepath.Join(env.dir, "etc/named.conf"))
+	c := string(conf)
+	for _, want := range []string{
+		"acl \"dhcp\" {\n\t// !10.0.10.150-10.0.10.160\n\t!10.0.10.150/31;\n\t!10.0.10.152/29;\n\t!10.0.10.160;\n\t// 10.0.10.101-10.0.10.199\n\t10.0.10.101;\n",
+		"\t10.0.10.192/29;\n\t// 2001:db8::100-2001:db8::1ff\n\t2001:db8::100/120;\n};\n",
+		"\tallow-query {\n\t\t// 10.0.20.1-10.0.20.6\n\t\t10.0.20.1;\n\t\t10.0.20.2/31;\n\t\t10.0.20.4/31;\n\t\t10.0.20.6;\n\t\tlocalhost;\n\t};\n",
+	} {
+		if !strings.Contains(c, want) {
+			t.Errorf("named.conf lacks %q:\n%s", want, c)
+		}
+	}
+	for _, l := range strings.Split(c, "\n") {
+		if code, _, _ := strings.Cut(l, "//"); strings.Contains(code, "-10.0.") || strings.Contains(code, "-2001:") {
+			t.Errorf("a range reached named.conf outside a comment: %q", l)
+		}
+	}
+
+	// Mistakes are caught when they're entered.
+	for _, tc := range []struct {
+		req  Request
+		want string
+	}{
+		{NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("bad"), Elements: &[]string{"10.0.10.199-10.0.10.101"}}), "start is after the end"},
+		{NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("bad"), Elements: &[]string{"10.0.10.101-199"}}), "not a full IP address"},
+		{optionReq("forwarders", "{ 192.0.2.1-192.0.2.9; }"), "only work in address match lists"},
+		{optionReq("allow-recursion", "{ 10.0.0.9-10.0.0.1; }"), "start is after the end"},
+		{NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("10.0.0.1-10.0.0.9"), Elements: &[]string{"10.0.0.1"}}), "looks like an address range"},
+	} {
+		if e := env.submitErr(env.admin, tc.req); !strings.Contains(e.Error(), tc.want) && !strings.Contains(describeProblems(e), tc.want) {
+			t.Errorf("%s: %v %s, want %q", tc.req.Op, e, describeProblems(e), tc.want)
+		}
+	}
+
+	// Validation sees what a range covers: everything is "any".
+	res := env.submit(env.admin, optionReq("allow-recursion", "0.0.0.0-255.255.255.255"))
+	if !hasProblem(res.Problems, "security_open_resolver") {
+		t.Errorf("no open resolver warning for 0.0.0.0-255.255.255.255: %+v", res.Problems)
+	}
+	// IPv6 ranges in the IPv4-mapped space get a warning.
+	res = env.submit(env.admin, NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("mapped"), Elements: &[]string{"::ffff:10.0.0.1-::ffff:10.0.0.9"}}))
+	if !hasProblem(res.Problems, "range_mapped4") {
+		t.Errorf("no range_mapped4 warning: %+v", res.Problems)
+	}
+}
+
+func TestClientGroupRanges(t *testing.T) {
+	env := newEnv(t)
+	setupZone(env)
+	_, srv := newListServer(t, "||ads.example^\n")
+	env.submit(env.admin,
+		NewRequest(OpACLCreate, 0, ACLInput{Name: model.Ptr("tablets"), Elements: &[]string{"10.0.0.50-10.0.0.51"}}),
+	)
+	env.submit(env.admin, blocklist("ads", srv.URL+"/a.txt"), clientGroup("kids", "off", "tablets", "10.0.0.20 - 10.0.0.23"))
+	if g := env.state().SortedClientGroups(); len(g) != 1 || strings.Join(g[0].Members, " ") != "tablets 10.0.0.20-10.0.0.23" {
+		t.Fatalf("groups = %+v", g)
+	}
+	b, err := os.ReadFile(filepath.Join(env.dir, "zones/_default/off.gate.jarl.invalid.rpz"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, want := range []string{"31.50.0.0.10.rpz-client-ip", "30.20.0.0.10.rpz-client-ip"} {
+		if !strings.Contains(string(b), want) {
+			t.Errorf("off gate lacks %s:\n%s", want, b)
+		}
+	}
+}

internal/iprange/iprange.go

@@ -0,0 +1,148 @@
+// Package iprange handles address ranges such as 10.0.10.101-10.0.10.199
+// or 2001:db8::100-2001:db8::1ff. BIND matches only addresses and
+// prefixes, so Jarl keeps a range as it was written and turns it into the
+// exact set of prefixes that covers it when it writes named.conf.
+package iprange
+
+import (
+	"fmt"
+	"math/big"
+	"net/netip"
+	"strings"
+)
+
+// Range is an inclusive range of addresses of one family.
+type Range struct {
+	Start, End netip.Addr
+}
+
+// String returns the range as Jarl writes it: START-END.
+func (r Range) String() string { return r.Start.String() + "-" + r.End.String() }
+
+// Parse parses START-END, both full addresses of the same family. ok is
+// false when s isn't meant as a range (no "-", or text before it that
+// isn't an address, such as the ACL name "branch-office"); err is set when
+// it is meant as one but is wrong.
+func Parse(s string) (r Range, ok bool, err error) {
+	left, right, found := strings.Cut(s, "-")
+	if !found {
+		return Range{}, false, nil
+	}
+	left, right = strings.TrimSpace(left), strings.TrimSpace(right)
+	if !looksLikeAddr(left) {
+		return Range{}, false, nil
+	}
+	start, err := netip.ParseAddr(left)
+	if err != nil {
+		return Range{}, true, fmt.Errorf("range %q: %q is not a full IP address", s, left)
+	}
+	end, err := netip.ParseAddr(right)
+	if err != nil {
+		if right == "" {
+			return Range{}, true, fmt.Errorf("range %q has no end address", s)
+		}
+		return Range{}, true, fmt.Errorf("range %q: %q is not a full IP address (write both ends in full, e.g. 10.0.10.101-10.0.10.199)", s, right)
+	}
+	if start.Zone() != "" || end.Zone() != "" {
+		return Range{}, true, fmt.Errorf("range %q: addresses with a zone (%%interface) can't be matched", s)
+	}
+	if start.Is4() != end.Is4() {
+		return Range{}, true, fmt.Errorf("range %q mixes IPv4 and IPv6", s)
+	}
+	if end.Less(start) {
+		return Range{}, true, fmt.Errorf("range %q: the start is after the end", s)
+	}
+	return Range{Start: start, End: end}, true, nil
+}
+
+// looksLikeAddr reports whether s could only be meant as an address: it
+// has a colon, or it is digits and dots with at least one dot.
+func looksLikeAddr(s string) bool {
+	if strings.Contains(s, ":") {
+		return true
+	}
+	if !strings.Contains(s, ".") {
+		return false
+	}
+	for i := 0; i < len(s); i++ {
+		if c := s[i]; !(c >= '0' && c <= '9' || c == '.') {
+			return false
+		}
+	}
+	return true
+}
+
+// Prefixes returns the fewest prefixes that together cover exactly the
+// range, in address order: 10.0.10.101-10.0.10.199 is 10.0.10.101/32,
+// 10.0.10.102/31, 10.0.10.104/29, 10.0.10.112/28, 10.0.10.128/26 and
+// 10.0.10.192/29. That is at most 62 prefixes for IPv4 and 254 for IPv6.
+func (r Range) Prefixes() []netip.Prefix {
+	var out []netip.Prefix
+	a := r.Start
+	for {
+		// The largest prefix that starts at a and ends at or before End.
+		p := netip.PrefixFrom(a, a.BitLen())
+		for bits := a.BitLen() - 1; bits >= 0; bits-- {
+			q := netip.PrefixFrom(a, bits)
+			if q.Masked().Addr() != a || r.End.Less(last(q)) {
+				break
+			}
+			p = q
+		}
+		out = append(out, p)
+		end := last(p)
+		if end == r.End {
+			return out
+		}
+		a = end.Next()
+	}
+}
+
+// last returns the last address of a prefix.
+func last(p netip.Prefix) netip.Addr {
+	b := p.Addr().AsSlice()
+	for i := p.Bits(); i < len(b)*8; i++ {
+		b[i/8] |= 0x80 >> (i % 8)
+	}
+	a, _ := netip.AddrFromSlice(b)
+	return a
+}
+
+// Size returns the number of addresses in the range.
+func (r Range) Size() *big.Int {
+	s := new(big.Int).SetBytes(r.Start.AsSlice())
+	e := new(big.Int).SetBytes(r.End.AsSlice())
+	return e.Sub(e, s).Add(e, big.NewInt(1))
+}
+
+// SizeText describes the size for people: "99 addresses", or a power of
+// two for very large IPv6 ranges ("about 2^80 addresses").
+func (r Range) SizeText() string {
+	n := r.Size()
+	if n.BitLen() <= 40 {
+		if n.Int64() == 1 {
+			return "1 address"
+		}
+		return n.String() + " addresses"
+	}
+	return fmt.Sprintf("about 2^%d addresses", n.BitLen()-1)
+}
+
+// Mapped4 is the IPv4-mapped IPv6 space; BIND can see IPv4 clients as
+// addresses in it.
+var Mapped4 = netip.MustParsePrefix("::ffff:0:0/96")
+
+// TouchesMapped4 reports whether an IPv6 range overlaps ::ffff:0:0/96.
+func (r Range) TouchesMapped4() bool {
+	if r.Start.Is4() {
+		return false
+	}
+	lo, hi := Mapped4.Addr(), last(Mapped4)
+	return !(r.End.Less(lo) || hi.Less(r.Start))
+}
+
+// FromPrefix returns the addresses of a prefix as a range.
+func FromPrefix(p netip.Prefix) Range {
+	p = p.Masked()
+	return Range{Start: p.Addr(), End: last(p)}
+}

internal/iprange/iprange_test.go

@@ -0,0 +1,123 @@
+package iprange
+
+import (
+	"math/rand"
+	"net/netip"
+	"strings"
+	"testing"
+)
+
+func TestParse(t *testing.T) {
+	for _, tc := range []struct {
+		in, want, err string
+		ok            bool
+	}{
+		{in: "10.0.10.101-10.0.10.199", want: "10.0.10.101-10.0.10.199", ok: true},
+		{in: "10.0.10.101 - 10.0.10.199", want: "10.0.10.101-10.0.10.199", ok: true},
+		{in: "2001:DB8::100-2001:db8::1ff", want: "2001:db8::100-2001:db8::1ff", ok: true},
+		{in: "10.0.0.5-10.0.0.5", want: "10.0.0.5-10.0.0.5", ok: true},
+		{in: "branch-office", ok: false},
+		{in: "10-net", ok: false},
+		{in: "10.0.0.0/24", ok: false},
+		{in: "10.0.10.101-199", ok: true, err: "not a full IP address"},
+		{in: "10.0.10.101-", ok: true, err: "no end address"},
+		{in: "2001:db8::100-1ff", ok: true, err: "not a full IP address"},
+		{in: "10.0.0.9-10.0.0.1", ok: true, err: "start is after the end"},
+		{in: "10.0.0.1-2001:db8::1", ok: true, err: "mixes IPv4 and IPv6"},
+		{in: "fe80::1%eth0-fe80::9%eth0", ok: true, err: "zone"},
+		{in: "10.0.300.1-10.0.300.9", ok: true, err: "not a full IP address"},
+		{in: "10.0.0.1-10.0.0.9-10.0.0.20", ok: true, err: "not a full IP address"},
+	} {
+		r, ok, err := Parse(tc.in)
+		if ok != tc.ok || (err == nil) != (tc.err == "") || err != nil && !strings.Contains(err.Error(), tc.err) {
+			t.Errorf("%s: ok=%v err=%v, want ok=%v err~%q", tc.in, ok, err, tc.ok, tc.err)
+			continue
+		}
+		if err == nil && ok && r.String() != tc.want {
+			t.Errorf("%s = %s, want %s", tc.in, r, tc.want)
+		}
+	}
+}
+
+func TestPrefixes(t *testing.T) {
+	for in, want := range map[string]string{
+		"10.0.10.101-10.0.10.199":                    "10.0.10.101/32 10.0.10.102/31 10.0.10.104/29 10.0.10.112/28 10.0.10.128/26 10.0.10.192/29",
+		"10.0.0.0-10.0.0.255":                        "10.0.0.0/24",
+		"10.0.0.5-10.0.0.5":                          "10.0.0.5/32",
+		"0.0.0.0-255.255.255.255":                    "0.0.0.0/0",
+		"255.255.255.254-255.255.255.255":            "255.255.255.254/31",
+		"2001:db8::100-2001:db8::1ff":                "2001:db8::100/120",
+		"::-ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff": "::/0",
+	} {
+		r, _, err := Parse(in)
+		if err != nil {
+			t.Fatal(err)
+		}
+		var got []string
+		for _, p := range r.Prefixes() {
+			got = append(got, p.String())
+		}
+		if strings.Join(got, " ") != want {
+			t.Errorf("%s = %s, want %s", in, strings.Join(got, " "), want)
+		}
+	}
+	// The worst cases stay small.
+	if n := len(must(t, "0.0.0.1-255.255.255.254").Prefixes()); n != 62 {
+		t.Errorf("worst IPv4 case = %d prefixes, want 62", n)
+	}
+	if n := len(must(t, "::1-ffff:ffff:ffff:ffff:ffff:ffff:ffff:fffe").Prefixes()); n != 254 {
+		t.Errorf("worst IPv6 case = %d prefixes, want 254", n)
+	}
+}
+
+// Every address of a random range is covered once, and nothing outside it.
+func TestPrefixesExact(t *testing.T) {
+	rnd := rand.New(rand.NewSource(1))
+	for i := 0; i < 300; i++ {
+		lo, hi := rnd.Intn(4096), rnd.Intn(4096)
+		if hi < lo {
+			lo, hi = hi, lo
+		}
+		base := []byte{10, 20, 0, 0}
+		addr := func(n int) netip.Addr {
+			return netip.AddrFrom4([4]byte{base[0], base[1], byte(n >> 8), byte(n)})
+		}
+		r := Range{Start: addr(lo), End: addr(hi)}
+		ps := r.Prefixes()
+		for n := max(lo-3, 0); n <= min(hi+3, 4095); n++ {
+			c := 0
+			for _, p := range ps {
+				if p.Contains(addr(n)) {
+					c++
+				}
+			}
+			if in := n >= lo && n <= hi; in && c != 1 || !in && c != 0 {
+				t.Fatalf("%s: %s covered %d times (%v)", r, addr(n), c, ps)
+			}
+		}
+		if got := r.Size().Int64(); got != int64(hi-lo+1) {
+			t.Fatalf("%s: size %d", r, got)
+		}
+	}
+}
+
+func TestSizeAndMapped(t *testing.T) {
+	if s := must(t, "10.0.10.101-10.0.10.199").SizeText(); s != "99 addresses" {
+		t.Errorf("size = %s", s)
+	}
+	if s := must(t, "2001:db8::-2001:db8:0:ffff:ffff:ffff:ffff:ffff").SizeText(); s != "about 2^80 addresses" {
+		t.Errorf("size = %s", s)
+	}
+	if !must(t, "::ffff:10.0.0.1-::ffff:10.0.0.9").TouchesMapped4() || must(t, "2001:db8::1-2001:db8::9").TouchesMapped4() || must(t, "10.0.0.1-10.0.0.9").TouchesMapped4() {
+		t.Error("TouchesMapped4")
+	}
+}
+
+func must(t *testing.T, s string) Range {
+	t.Helper()
+	r, ok, err := Parse(s)
+	if !ok || err != nil {
+		t.Fatalf("%s: %v %v", s, ok, err)
+	}
+	return r
+}

internal/model/blocking.go

@@ -7,6 +7,8 @@ import (
 	"sort"
 	"strings"
 	"time"
+
+	"jarl/internal/iprange"
 )
 
 // Blocklist is a list of domains to block, downloaded from URL and kept up
@@ -268,6 +270,8 @@ func (s *State) GroupPrefixes(g *ClientGroup) []netip.Prefix {
 				out = append(out, netip.PrefixFrom(a, a.BitLen()))
 			} else if p, err := netip.ParsePrefix(e); err == nil {
 				out = append(out, p.Masked())
+			} else if r, ok, err := iprange.Parse(e); ok && err == nil {
+				out = append(out, r.Prefixes()...)
 			} else if acl := s.ACLByName(e); acl != nil && !seen[acl.Name] {
 				seen[acl.Name] = true
 				add(acl.Elements)

internal/namedconf/acl.go

@@ -6,6 +6,8 @@ import (
 	"net/netip"
 	"strconv"
 	"strings"
+
+	"jarl/internal/iprange"
 )
 
 // AMKind is the kind of an address match list element.
@@ -17,6 +19,9 @@ const (
 	AMName                 // an ACL name (or built-in ACL)
 	AMNested               // { ... }
 	AMOther                // anything else (e.g. geoip), passed through
+	// AMRange is an address range, START-END: Jarl's own syntax, written
+	// to named.conf as the prefixes that cover it (ExpandRanges).
+	AMRange
 )
 
 // Builtin ACL names.
@@ -26,10 +31,11 @@ var BuiltinACLs = map[string]bool{"any": true, "none": true, "localhost": true,
 type AMElement struct {
 	Negated bool
 	Kind    AMKind
-	Prefix  netip.Prefix // AMPrefix
-	Name    string       // AMKey, AMName
-	Nested  []AMElement  // AMNested
-	Raw     string       // AMOther
+	Prefix  netip.Prefix  // AMPrefix
+	Name    string        // AMKey, AMName
+	Nested  []AMElement   // AMNested
+	Raw     string        // AMOther
+	Range   iprange.Range // AMRange
 }
 
 // String returns the element in canonical named.conf syntax, without the
@@ -55,6 +61,8 @@ func (e AMElement) String() string {
 		s = "{ " + strings.Join(parts, " ") + " }"
 	case AMOther:
 		s = e.Raw
+	case AMRange:
+		s = e.Range.String()
 	}
 	if e.Negated {
 		return "!" + s
@@ -137,6 +145,7 @@ func parseAMItems(items []Item) (AMElement, error) {
 	if len(items) == 0 {
 		return e, errors.New("empty address match element")
 	}
+	items = joinRange(items)
 	first := items[0]
 	if first.Block != nil {
 		if len(items) != 1 {
@@ -172,6 +181,16 @@ func parseAMItems(items []Item) (AMElement, error) {
 		}
 		return e, fmt.Errorf("unexpected text after %q", word)
 	}
+	if !first.Value.Quoted {
+		if r, ok, err := iprange.Parse(word); ok {
+			if err != nil {
+				return e, err
+			}
+			e.Kind = AMRange
+			e.Range = r
+			return e, nil
+		}
+	}
 	if !first.Value.Quoted || BuiltinACLs[lw] {
 		if p, ok, err := parsePrefix(word); ok {
 			if err != nil {
@@ -215,6 +234,9 @@ func CheckACLName(name string) error {
 			return fmt.Errorf("ACL name %q looks like an address", name)
 		}
 	}
+	if _, ok, _ := iprange.Parse(name); ok {
+		return fmt.Errorf("ACL name %q looks like an address range", name)
+	}
 	return nil
 }
 
@@ -318,18 +340,18 @@ func AMRefs(elems []AMElement) (acls, keys []string) {
 func Shadowed(elems []AMElement) []string {
 	var warns []string
 	for i, e := range elems {
-		if e.Kind != AMPrefix && e.Kind != AMName {
+		if e.Kind != AMPrefix && e.Kind != AMRange && e.Kind != AMName {
 			continue
 		}
+		er, eok := e.addrRange()
 		for j := 0; j < i; j++ {
 			prev := elems[j]
 			if prev.Kind == AMName && prev.Name == "any" {
 				warns = append(warns, fmt.Sprintf("element %q never matches: %q before it already matches every address", e.String(), prev.String()))
 				break
 			}
-			if prev.Kind == AMPrefix && e.Kind == AMPrefix &&
-				prev.Prefix.Addr().Is4() == e.Prefix.Addr().Is4() &&
-				prev.Prefix.Bits() <= e.Prefix.Bits() && prev.Prefix.Contains(e.Prefix.Addr()) {
+			if pr, ok := prev.addrRange(); ok && eok && pr.Start.Is4() == er.Start.Is4() &&
+				!er.Start.Less(pr.Start) && !pr.End.Less(er.End) {
 				warns = append(warns, fmt.Sprintf("element %q never matches: %q before it already covers it (first match wins; put the more specific element first)", e.String(), prev.String()))
 				break
 			}
@@ -338,6 +360,117 @@ func Shadowed(elems []AMElement) []string {
 	return warns
 }
 
+// addrRange returns the addresses a prefix or range element covers.
+func (e AMElement) addrRange() (iprange.Range, bool) {
+	switch e.Kind {
+	case AMRange:
+		return e.Range, true
+	case AMPrefix:
+		return iprange.FromPrefix(e.Prefix), true
+	}
+	return iprange.Range{}, false
+}
+
+// Expand returns the element as named.conf can take it: a range becomes
+// the prefixes that cover it (each negated when the range is), nested
+// lists are expanded too, and anything else is returned as it is.
+func (e AMElement) Expand() []AMElement {
+	switch e.Kind {
+	case AMRange:
+		var out []AMElement
+		for _, p := range e.Range.Prefixes() {
+			out = append(out, AMElement{Negated: e.Negated, Kind: AMPrefix, Prefix: p})
+		}
+		return out
+	case AMNested:
+		n := e
+		n.Nested = nil
+		for _, in := range e.Nested {
+			n.Nested = append(n.Nested, in.Expand()...)
+		}
+		return []AMElement{n}
+	}
+	return []AMElement{e}
+}
+
+// joinRange turns a range written with spaces around the dash
+// ("10.0.0.1 - 10.0.0.9", three words) into a single word.
+func joinRange(items []Item) []Item {
+	if len(items) != 3 || items[0].Value == nil || items[1].Value == nil || items[2].Value == nil ||
+		items[0].Value.Quoted || items[1].Value.Quoted || items[2].Value.Quoted || items[1].Value.Text != "-" {
+		return items
+	}
+	text := items[0].Value.Text + "-" + items[2].Value.Text
+	if _, ok, _ := iprange.Parse(text); !ok {
+		return items
+	}
+	return []Item{{Value: &Value{Text: text, Pos: items[0].Value.Pos}}}
+}
+
+// JoinRanges rewrites ranges written with spaces around the dash, in st's
+// blocks, as single words (the form Jarl stores).
+func JoinRanges(st *Stmt) {
+	for _, it := range st.Items {
+		if it.Block == nil {
+			continue
+		}
+		for _, s := range it.Block.Stmts {
+			if len(s.Items) == 4 && s.Items[0].Bang {
+				s.Items = append(s.Items[:1], joinRange(s.Items[1:])...)
+			} else {
+				s.Items = joinRange(s.Items)
+			}
+			JoinRanges(s)
+		}
+	}
+}
+
+// ExpandRanges replaces the address ranges in st's blocks (at any depth)
+// by the prefixes that cover them, with the range as a comment, so named
+// can read it. A range is a block statement that is a single word START-END,
+// optionally negated; nothing else in named.conf's grammar looks like one.
+func ExpandRanges(st *Stmt) {
+	for _, it := range st.Items {
+		if it.Block != nil {
+			expandBlock(it.Block)
+		}
+	}
+}
+
+func expandBlock(b *Block) {
+	var out []*Stmt
+	for _, s := range b.Stmts {
+		items, neg := s.Items, false
+		if len(items) == 2 && items[0].Bang {
+			items, neg = items[1:], true
+		}
+		if len(items) == 1 && items[0].Value != nil && !items[0].Value.Quoted {
+			if r, ok, err := iprange.Parse(items[0].Value.Text); ok && err == nil {
+				for i, p := range r.Prefixes() {
+					var ns Stmt
+					if neg {
+						ns.Items = append(ns.Items, Item{Bang: true})
+					}
+					text := p.String()
+					if p.IsSingleIP() {
+						text = p.Addr().String()
+					}
+					ns.Items = append(ns.Items, Item{Value: &Value{Text: text}})
+					ns.Pos = s.Pos
+					if i == 0 {
+						ns.Comment = AMElement{Negated: neg, Kind: AMRange, Range: r}.String()
+					}
+					out = append(out, &ns)
+				}
+				continue
+			}
+		}
+		ExpandRanges(s)
+		out = append(out, s)
+	}
+	b.Stmts = out
+}
+
 // ContainsAny reports whether elems contain a non-negated "any" before any
 // negated element would restrict it, which makes the list match everyone.
 // It is used for security lints (open resolvers, open transfers).

internal/namedconf/ast.go

@@ -30,6 +30,9 @@ type Item struct {
 type Stmt struct {
 	Items []Item
 	Pos   Pos
+	// Comment is written before the statement (only by Jarl: comments in
+	// parsed text are dropped). ExpandRanges notes the range there.
+	Comment string
 }
 
 // Keyword returns the statement's first word, lowercased, or "" if the

internal/namedconf/printer.go

@@ -77,6 +77,9 @@ func valueText(v *Value) string {
 
 func writeStmt(sb *strings.Builder, s *Stmt, indent int) {
 	tabs := strings.Repeat("\t", indent)
+	if s.Comment != "" {
+		sb.WriteString(tabs + "// " + s.Comment + "\n")
+	}
 	sb.WriteString(tabs)
 	inline := Compact(s.Items)
 	if !hasNestedBlocks(s.Items) && len(inline)+indent*8 <= maxInline+8 {
@@ -167,6 +170,9 @@ func writeItemsInline(sb *strings.Builder, items []Item) {
 			} else {
 				sb.WriteString("{ ")
 				for _, s := range it.Block.Stmts {
+					if s.Comment != "" {
+						sb.WriteString("/* " + s.Comment + " */ ")
+					}
 					writeItemsInline(sb, s.Items)
 					sb.WriteString("; ")
 				}

internal/namedconf/range_test.go

@@ -0,0 +1,90 @@
+package namedconf
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestRangeElements(t *testing.T) {
+	e, err := ParseAMElement("!10.0.10.150 - 10.0.10.160;")
+	if err != nil || e.Kind != AMRange || !e.Negated || e.String() != "!10.0.10.150-10.0.10.160" {
+		t.Fatalf("negated range = %+v, %v", e, err)
+	}
+	if e, err := ParseAMElement("2001:db8::100-2001:db8::1ff"); err != nil || e.Kind != AMRange {
+		t.Errorf("IPv6 range = %+v, %v", e, err)
+	}
+	// ACL names with dashes are still names.
+	if e, err := ParseAMElement("branch-office"); err != nil || e.Kind != AMName {
+		t.Errorf("name = %+v, %v", e, err)
+	}
+	for _, bad := range []string{"10.0.10.199-10.0.10.101", "10.0.10.101-199", "10.0.0.1-2001:db8::1"} {
+		if _, err := ParseAMElement(bad); err == nil {
+			t.Errorf("%s accepted", bad)
+		}
+	}
+	if err := CheckACLName("10.0.0.1-10.0.0.9"); err == nil {
+		t.Error("an ACL name that looks like a range was accepted")
+	}
+	var got []string
+	for _, x := range e.Expand() {
+		got = append(got, x.String())
+	}
+	if strings.Join(got, " ") != "!10.0.10.150/31 !10.0.10.152/29 !10.0.10.160" {
+		t.Errorf("expand = %v", got)
+	}
+}
+
+func TestExpandRanges(t *testing.T) {
+	st, err := ParseStatement(`acl "lan" { !10.0.10.150-10.0.10.160; 10.0.10.101-10.0.10.199; key xfer; branch-office; { 10.0.0.1-10.0.0.2; }; }`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	ExpandRanges(st)
+	want := `acl "lan" {
+	// !10.0.10.150-10.0.10.160
+	!10.0.10.150/31;
+	!10.0.10.152/29;
+	!10.0.10.160;
+	// 10.0.10.101-10.0.10.199
+	10.0.10.101;
+	10.0.10.102/31;
+	10.0.10.104/29;
+	10.0.10.112/28;
+	10.0.10.128/26;
+	10.0.10.192/29;
+	key xfer;
+	branch-office;
+	{ /* 10.0.0.1-10.0.0.2 */ 10.0.0.1; 10.0.0.2; };
+};
+`
+	if got := FormatStmt(st, 0); got != want {
+		t.Errorf("got:\n%s\nwant:\n%s", got, want)
+	}
+	// Short lists stay on one line, with the range as a /* */ comment;
+	// both forms parse again.
+	st, _ = ParseOptionValue("allow-query", "{ 2001:db8::100-2001:db8::1ff; localhost; }")
+	ExpandRanges(st)
+	got := FormatStmt(st, 0)
+	if got != "allow-query { /* 2001:db8::100-2001:db8::1ff */ 2001:db8::100/120; localhost; };\n" {
+		t.Errorf("inline = %q", got)
+	}
+	if _, err := ParseStatement(strings.TrimSuffix(strings.TrimSpace(got), ";")); err != nil {
+		t.Errorf("output doesn't parse: %v", err)
+	}
+}
+
+func TestShadowedRanges(t *testing.T) {
+	elems, _ := ParseAMListString("10.0.10.0/24; 10.0.10.101-10.0.10.199; 10.0.10.150-10.0.11.5; 10.0.11.1")
+	w := Shadowed(elems)
+	if len(w) != 2 || !strings.Contains(w[0], `"10.0.10.101-10.0.10.199" never matches`) || !strings.Contains(w[1], `"10.0.11.1" never matches: "10.0.10.150-10.0.11.5"`) {
+		t.Errorf("shadowed = %q", w)
+	}
+	elems, _ = ParseAMListString("10.0.10.101-10.0.10.199; 10.0.10.120")
+	if w := Shadowed(elems); len(w) != 1 || !strings.Contains(w[0], `"10.0.10.120" never matches`) {
+		t.Errorf("shadowed by a range = %q", w)
+	}
+	elems, _ = ParseAMListString("0.0.0.0-255.255.255.255")
+	if ContainsAny(elems) {
+		t.Error("ContainsAny should only see expanded elements") // callers expand first
+	}
+}

internal/render/render.go

@@ -229,7 +229,7 @@ func optionText(o *model.Option, indent int) string {
 		// named-checkconf reports the problem.
 		return prefix + strings.Repeat("\t", indent) + o.Text() + "\n"
 	}
-	return prefix + namedconf.FormatStmt(st, indent)
+	return prefix + formatStmt(st, indent)
 }
 
 func indentLines(s string, indent int) string {
@@ -313,7 +313,7 @@ func renderConfig(s *model.State, p Paths, x Extras, out *Output) (string, []Spa
 			if err != nil {
 				w.write("acl " + namedconf.QuoteString(a.Name) + " " + amlBlock(a.Elements) + ";\n")
 			} else {
-				w.write(namedconf.FormatStmt(st, 0))
+				w.write(formatStmt(st, 0))
 			}
 			w.end()
 		}
@@ -382,7 +382,7 @@ func writeAML(w *confWriter, name string, elems []string) {
 		w.write("\t" + name + " " + amlBlock(elems) + ";\n")
 		return
 	}
-	w.write(namedconf.FormatStmt(st, 1))
+	w.write(formatStmt(st, 1))
 }
 
 func yesNo(b bool) string {
@@ -507,3 +507,10 @@ func ZoneContentHash(s *model.State, z *model.Zone) string {
 	}
 	return hex.EncodeToString(h.Sum(nil))
 }
+
+// formatStmt lays out a statement for named.conf, with address ranges
+// (Jarl's own syntax) written as the prefixes that cover them.
+func formatStmt(st *namedconf.Stmt, indent int) string {
+	namedconf.ExpandRanges(st)
+	return namedconf.FormatStmt(st, indent)
+}

internal/render/stats.go

@@ -62,13 +62,13 @@ func (h *StatsHooks) statsStatement(user *model.Option) string {
 				}
 			}
 			b.Stmts = append(b.Stmts, h.statsInet())
-			return commentLines(user.Comment) + commentBlock("//", statsComment) + namedconf.FormatStmt(st, 0)
+			return commentLines(user.Comment) + commentBlock("//", statsComment) + formatStmt(st, 0)
 		}
 		// Unparsable: validation reports it; leave it alone.
 		return optionText(user, 0)
 	}
 	st := namedconf.NewStmt("statistics-channels", namedconf.NewBlock(h.statsInet()))
-	return commentBlock("//", statsComment) + namedconf.FormatStmt(st, 0)
+	return commentBlock("//", statsComment) + formatStmt(st, 0)
 }
 
 // loggingStatement returns the logging statement with Jarl's channel and
@@ -108,7 +108,7 @@ func (h *StatsHooks) loggingStatement(user *model.Option, rpz bool) string {
 	if user != nil {
 		prefix = commentLines(user.Comment)
 	}
-	return prefix + commentBlock("//", statsComment) + namedconf.FormatStmt(st, 0)
+	return prefix + commentBlock("//", statsComment) + formatStmt(st, 0)
 }
 
 func commentLines(c string) string {

internal/server/h_config.go

@@ -13,6 +13,7 @@ import (
 	"jarl/internal/catalog"
 	"jarl/internal/dnsname"
 	"jarl/internal/engine"
+	"jarl/internal/iprange"
 	"jarl/internal/model"
 	"jarl/internal/render"
 	"jarl/internal/rr"
@@ -554,6 +555,42 @@ func (s *Server) catalogRRTypes(w http.ResponseWriter, r *http.Request, p *auth.
 	return nil
 }
 
+// catalogRanges: GET /catalog/ranges?r=A-B,C-D shows the prefixes each
+// address range is written to named.conf as (the web UI shows them while
+// you type). Text that isn't a range is left out; a range with a mistake
+// comes back with its error.
+func (s *Server) catalogRanges(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
+	type rangeInfo struct {
+		Input    string   `json:"input"`
+		Range    string   `json:"range,omitempty"`
+		Prefixes []string `json:"prefixes,omitempty"`
+		Size     string   `json:"size,omitempty"`
+		Error    string   `json:"error,omitempty"`
+	}
+	out := []rangeInfo{}
+	for _, in := range strings.Split(r.URL.Query().Get("r"), ",") {
+		in = strings.TrimSpace(in)
+		if in == "" || len(out) >= 100 {
+			continue
+		}
+		rg, ok, err := iprange.Parse(strings.TrimSpace(strings.TrimPrefix(in, "!")))
+		switch {
+		case !ok:
+			continue
+		case err != nil:
+			out = append(out, rangeInfo{Input: in, Error: err.Error()})
+		default:
+			ri := rangeInfo{Input: in, Range: rg.String(), Size: rg.SizeText()}
+			for _, pf := range rg.Prefixes() {
+				ri.Prefixes = append(ri.Prefixes, pf.String())
+			}
+			out = append(out, ri)
+		}
+	}
+	writeJSON(w, http.StatusOK, out)
+	return nil
+}
+
 func (s *Server) catalogGrants(w http.ResponseWriter, r *http.Request, p *auth.Principal) error {
 	roles := map[string][]string{}
 	for name, gs := range auth.RoleTemplates {

internal/server/ranges_test.go

@@ -0,0 +1,31 @@
+package server
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+func TestCatalogRanges(t *testing.T) {
+	e := newAPIEnv(t)
+	b, status := e.req("GET", "/catalog/ranges?r=10.0.10.101-10.0.10.199,!2001:db8::100-2001:db8::1ff,branch-office,10.0.0.9-10.0.0.1", e.token, nil)
+	if status != 200 {
+		t.Fatalf("status %d: %s", status, b)
+	}
+	var out []struct {
+		Input, Range, Size, Error string
+		Prefixes                  []string
+	}
+	json.Unmarshal(b, &out)
+	if len(out) != 3 {
+		t.Fatalf("got %s", b)
+	}
+	if out[0].Range != "10.0.10.101-10.0.10.199" || len(out[0].Prefixes) != 6 || out[0].Size != "99 addresses" {
+		t.Errorf("IPv4 = %+v", out[0])
+	}
+	if out[1].Input != "!2001:db8::100-2001:db8::1ff" || len(out[1].Prefixes) != 1 || out[1].Prefixes[0] != "2001:db8::100/120" {
+		t.Errorf("IPv6 = %+v", out[1])
+	}
+	if out[2].Error == "" {
+		t.Errorf("reversed range = %+v", out[2])
+	}
+}

internal/server/routes.go

@@ -136,6 +136,7 @@ func (s *Server) routes() {
 	m.HandleFunc("GET "+p+"/catalog/options", s.authed(s.catalogOptions))
 	m.HandleFunc("GET "+p+"/catalog/rrtypes", s.authed(s.catalogRRTypes))
 	m.HandleFunc("GET "+p+"/catalog/grants", s.authed(s.catalogGrants))
+	m.HandleFunc("GET "+p+"/catalog/ranges", s.authed(s.catalogRanges))
 	m.HandleFunc("GET "+p+"/search", s.authed(s.search))
 	// Changesets
 	m.HandleFunc("POST "+p+"/apply", s.authed(s.applyBatch))

internal/validate/blocking.go

@@ -4,6 +4,7 @@ import (
 	"net/netip"
 	"strings"
 
+	"jarl/internal/iprange"
 	"jarl/internal/model"
 	"jarl/internal/namedconf"
 )
@@ -162,6 +163,9 @@ func (c *checker) checkMember(g *model.ClientGroup, m string, seen map[string]bo
 	if _, err := netip.ParsePrefix(m); err == nil {
 		return
 	}
+	if _, ok, err := iprange.Parse(m); ok && err == nil {
+		return
+	}
 	acl := c.s.ACLByName(m)
 	if acl == nil {
 		c.errf("client_group_member_invalid", "clientgroup", g.ID, "client group %s: %q is not an address, a prefix or an ACL", g.Name, m)

internal/validate/config.go

@@ -126,6 +126,7 @@ func (c *checker) checkACLs() {
 			c.warnf("acl_empty", "acl", a.ID, "%s is empty and matches nothing", label)
 		}
 		c.checkRefs(elems, label, "acl", a.ID)
+		c.checkRanges(elems, label, "acl", a.ID)
 		for _, w := range namedconf.Shadowed(elems) {
 			c.warnf("acl_shadowed", "acl", a.ID, "%s: %s", label, w)
 		}
@@ -179,6 +180,7 @@ func (c *checker) checkViews() {
 				c.errf("view_acl_invalid", "view", v.ID, "%s: %s element %q: %v", label, field, s, err)
 			})
 			c.checkRefs(elems, label+" "+field, "view", v.ID)
+			c.checkRanges(elems, label+" "+field, "view", v.ID)
 			for _, w := range namedconf.Shadowed(elems) {
 				c.warnf("acl_shadowed", "view", v.ID, "%s %s: %s", label, field, w)
 			}
@@ -237,11 +239,24 @@ func (c *checker) flatten(list []string, depth int) []namedconf.AMElement {
 				continue
 			}
 		}
-		out = append(out, e)
+		out = append(out, e.Expand()...)
 	}
 	return out
 }
 
+// checkRanges warns about IPv6 ranges in the IPv4-mapped space, which may
+// match IPv4 clients too.
+func (c *checker) checkRanges(elems []namedconf.AMElement, where, objType string, id int64) {
+	for _, e := range elems {
+		if e.Kind == namedconf.AMRange && e.Range.TouchesMapped4() {
+			c.warnf("range_mapped4", objType, id, "%s: range %s reaches into ::ffff:0:0/96, where named can see IPv4 clients as IPv6 addresses, so it may match IPv4 clients too; for IPv4 clients, write an IPv4 range", where, e.Range)
+		}
+		if e.Kind == namedconf.AMNested {
+			c.checkRanges(e.Nested, where, objType, id)
+		}
+	}
+}
+
 // optionScope maps an option to its catalog scope.
 func (c *checker) optionScope(o *model.Option) (string, string, bool) {
 	switch o.Scope {

internal/web/static/assets/aml.js

@@ -16,6 +16,8 @@ export async function amlContext() {
 }
 
 const ipRe = /^(\d{1,3}(\.\d{1,3}){0,3}|[0-9a-f:]*:[0-9a-f:.]*)(\/\d{1,3})?$/i;
+// rangeRe finds address ranges (START-END); the server checks them.
+const rangeRe = /!?\s*[0-9a-f]*[.:][0-9a-f:.]*\s*-\s*[0-9a-f]*[.:][0-9a-f:.]*/gi;
 
 // checkElement returns a problem with one element, or "".
 function checkElement(line, ctx, exclude) {
@@ -24,6 +26,7 @@ function checkElement(line, ctx, exclude) {
   if (e.startsWith("!")) e = e.slice(1).trim();
   const lower = e.toLowerCase();
   if (builtins.includes(lower) || ipRe.test(e) || e.startsWith("{") || lower.startsWith("geoip ")) return "";
+  if (e.replace(rangeRe, "").trim() === "") return ""; // a range: rangeHints explains it
   const key = e.match(/^key\s+"?([^"\s]+)"?$/i);
   if (key) return ctx.keys.some((k) => k.toLowerCase() === key[1].toLowerCase()) ? "" : "no TSIG key called " + key[1];
   if (/\s/.test(e)) return "";
@@ -32,6 +35,33 @@ function checkElement(line, ctx, exclude) {
   return ctx.acls.some((a) => a.name.toLowerCase() === name.toLowerCase()) ? "" : "no ACL called " + name + (ctx.acls.length ? "" : " (there are no ACLs yet)");
 }
 
+// rangeHints shows, below a field, what each address range in it
+// (10.0.10.101-10.0.10.199) becomes in named.conf, which only knows
+// prefixes, and what is wrong with a range that can't be used.
+export function rangeHints(field) {
+  const box = h("div", { class: "range-hints" });
+  let timer, last = "";
+  const update = async () => {
+    const found = (field.value.match(rangeRe) || []).map((r) => r.replace(/\s+/g, ""));
+    const key = found.join(",");
+    if (key === last) return;
+    last = key;
+    if (!found.length) { mount(box); return; }
+    try {
+      const info = await get("/catalog/ranges", { r: key });
+      if (key !== last) return;
+      mount(box, info.map((x) => x.error
+        ? h("div", { class: "msg warn small" }, x.error)
+        : h("details", { class: "range-hint small" },
+          h("summary", null, h("span", { class: "mono" }, x.input), " = " + x.size + ", written to named.conf as " + (x.prefixes.length === 1 ? "1 prefix" : x.prefixes.length + " prefixes")),
+          h("div", { class: "prefixes mono" }, x.prefixes.map((p) => h("span", null, p))))));
+    } catch { mount(box); }
+  };
+  field.addEventListener("input", () => { clearTimeout(timer); timer = setTimeout(update, 300); });
+  update();
+  return box;
+}
+
 // suggestions adds clickable names below a text field. mode "lines" adds
 // one element per line (and checks the names); "inline" inserts
 // "name; " at the cursor in named.conf syntax.
@@ -58,7 +88,7 @@ export function suggestions(field, ctx, { mode = "lines", exclude = "" } = {}) {
     acls.length ? [h("span", { class: "muted small" }, "ACLs:"), acls.map((a) => chip(a.name, a.name, a.detail))] : null,
     ctx.keys.length ? [h("span", { class: "muted small" }, "Keys:"), ctx.keys.map((k) => chip("key " + k, "key " + k, "TSIG key"))] : null,
     h("span", { class: "muted small" }, "Built-in:"), builtins.map((b) => chip(b, b, { any: "every address", none: "no address", localhost: "this server's own addresses", localnets: "networks this server is directly attached to" }[b])),
-    mode === "lines" ? h("span", { class: "muted small" }, "Prefix a line with ! to exclude it.") : null);
+    mode === "lines" ? h("span", { class: "muted small" }, "Prefix a line with ! to exclude it. Ranges: 10.0.10.101-10.0.10.199.") : null);
   if (mode === "lines") {
     const check = () => {
       const msgs = field.value.split("\n").map((l) => [l.trim(), checkElement(l, ctx, exclude)]).filter(([, m]) => m);
@@ -67,5 +97,5 @@ export function suggestions(field, ctx, { mode = "lines", exclude = "" } = {}) {
     field.addEventListener("input", check);
     check();
   }
-  return h("div", { class: "aml" }, row, problems);
+  return h("div", { class: "aml" }, row, problems, rangeHints(field));
 }

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

@@ -30,7 +30,7 @@ async function aclDialog(a) {
   const comment = input({ value: a ? a.comment : "" });
   await modal(a ? "Edit ACL " + a.name : "New ACL", h("div", null, h("div", { class: "form-grid" },
     field("Name", name, a ? "Renaming updates every reference automatically." : ""),
-    field("Elements", h("div", null, elems, suggestions(elems, ctx, { exclude: a ? a.name : "" })), "One per line: address, prefix (host bits must be zero), !negated, key NAME, another ACL's name, any/none/localhost/localnets."),
+    field("Elements", h("div", null, elems, suggestions(elems, ctx, { exclude: a ? a.name : "" })), "One per line: address, prefix (host bits must be zero), range (10.0.10.101-10.0.10.199), !negated, key NAME, another ACL's name, any/none/localhost/localnets."),
     field("Comment", comment)), err), [
     { label: "Cancel", value: null },
     { label: a ? "Save" : "Create ACL", kind: "primary", onclick: async () => {

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

@@ -3,6 +3,7 @@ import { h, mount, table, field, input, select, checkbox, toast, errorBox, badge
 import { get, change, describeResult, draftQuery, can, api } from "../api.js";
 import { rerender } from "../app.js";
 import { pendingBadge } from "./zones.js";
+import { rangeHints } from "../aml.js";
 
 // Well-known lists in Adblock format (they say which entries cover
 // subdomains). Sizes change; these are rough guides.
@@ -355,7 +356,7 @@ async function del(path, what) {
 function devicesPanel(groups, steps, views, autoViews, writable) {
   const live = steps.filter((s) => s.pending !== "delete");
   const name = input({ placeholder: "kids", class: "mono", style: { width: "9em" } });
-  const members = input({ placeholder: "10.10.0.50 10.10.0.51 or an ACL", class: "mono" });
+  const members = input({ placeholder: "10.10.0.50 10.10.0.20-10.10.0.29 or an ACL", class: "mono" });
   const step = stepSelect(steps, live.length ? live[0].name : "off", true);
   const vp = viewPicker(views, autoViews);
   const err = h("div");
@@ -368,7 +369,7 @@ function devicesPanel(groups, steps, views, autoViews, writable) {
     } catch (e) { mount(err, errorBox(e)); }
   } },
     h("div", { class: "f" }, h("label", null, "Group"), name),
-    h("div", { class: "f grow" }, h("label", null, "Devices"), members),
+    h("div", { class: "f grow" }, h("label", null, "Devices"), members, rangeHints(members)),
     h("div", { class: "f" }, h("label", null, "Step"), step),
     vp.el,
     h("div", { class: "f" }, h("label", null, " "), h("button", { class: "primary", type: "submit" }, "Add group")));
@@ -389,9 +390,10 @@ function devicesPanel(groups, steps, views, autoViews, writable) {
     ].filter(Boolean), groups, { empty: "No groups: every device is at normal.", rowClass: (g) => g.pending ? "pending-" + g.pending : "" }));
 }
 
-// splitMembers turns "a, b c" into a list.
+// splitMembers turns "a, b c" into a list; a range may have spaces
+// around its dash.
 function splitMembers(s) {
-  return s.split(/[\s,;]+/).map((x) => x.trim()).filter(Boolean);
+  return s.replace(/\s*-\s*/g, "-").split(/[\s,;]+/).map((x) => x.trim()).filter(Boolean);
 }
 
 // stepsLine shows the steps in order, with controls for the ones above
@@ -463,7 +465,7 @@ function editGroup(g, steps, views, autoViews) {
   const vp = viewPicker(views, autoViews, ownViews(g));
   editDialog("Edit client group " + g.name, "/blocking/groups/" + g.id, [
     ["Name", name],
-    ["Devices", members, "Addresses, networks (10.10.0.0/24) or ACLs, separated by spaces. A device can be in one group; a more specific address in another group wins."],
+    ["Devices", h("div", null, members, rangeHints(members)), "Addresses, networks (10.10.0.0/24), ranges (10.10.0.20-10.10.0.49) or ACLs, separated by spaces. A device can be in one group; a more specific address in another group wins."],
     ["Step", step],
     vp.picker ? ["Views", vp.picker, "None ticked: every view with blocking."] : null,
     ["Comment", comment],

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

@@ -25,7 +25,7 @@ function valueWidget(stmt, value, ctx) {
   if (kind === "address_match_list") {
     const inner = (value || "").replace(/^\s*\{\s*/, "").replace(/\s*\}\s*$/, "");
     const t = textarea(inner.split(";").map((s) => s.trim()).filter(Boolean).join("\n"), { class: "mono", rows: 4, placeholder: "192.168.1.0/24\n!192.168.1.66\nkey xfer-key\nlocalhost" });
-    return { el: h("div", null, t, ctx ? suggestions(t, ctx) : null), get: () => "{ " + lines(t.value).map((l) => l.replace(/;$/, "") + ";").join(" ") + " }", hint: "One element per line: address or prefix, !negated, key NAME, ACL name, any, none, localhost, localnets. First match wins." };
+    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, prefix or range (10.0.10.101-10.0.10.199), !negated, key NAME, ACL name, any, none, localhost, localnets. First match wins." };
   }
   if (kind === "raw") {
     const t = codeArea(value || "");

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

@@ -128,7 +128,7 @@ async function viewForm(v, viewless) {
   const adopt = checkbox("Move the " + viewless.length + " zone(s) that are not in a view into this view", true);
   const body = h("div", null, h("div", { class: "form-grid" },
     field("Name", name),
-    field("Match clients", h("div", null, mc, suggestions(mc, ctx)), "One element per line: addresses, prefixes, ACL names, key NAME, any/none/localhost/localnets; !negates. First match wins."),
+    field("Match clients", h("div", null, mc, suggestions(mc, ctx)), "One element per line: addresses, prefixes, ranges (10.0.10.101-10.0.10.199), ACL names, key NAME, any/none/localhost/localnets; !negates. First match wins."),
     field("Match destinations", h("div", null, md, suggestions(md, ctx)), "Server addresses this view answers on (optional)."),
     field("Recursive only", mro, "If yes, only recursive queries match this view."),
     field("Comment", comment),

internal/web/static/assets/style.css

@@ -426,6 +426,11 @@ td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
 button.chip { padding: 1px 8px; font-size: 12px; font-family: var(--mono); border-radius: 999px; background: var(--info-soft); border: 1px solid var(--border); color: var(--text); }
 button.chip:hover { background: var(--accent-soft); border-color: var(--accent); }
 .aml-problems .msg { margin: 4px 0 0; padding: 3px 8px; }
+.range-hints .msg { margin: 4px 0 0; padding: 3px 8px; }
+.range-hint { margin-top: 4px; color: var(--muted); }
+.range-hint summary { cursor: pointer; }
+.range-hint .prefixes { display: flex; flex-wrap: wrap; gap: 2px 12px; margin: 2px 0 0 14px; }
+.range-hint .prefixes span { white-space: nowrap; }
 
 /* Zone name and record previews. */
 .segmented button { border: none; border-right: 1px solid var(--border); border-radius: 0; background: transparent; padding: 4px 12px; color: var(--text); }