Reverse zones made easy: suggested, filled, in the right view, PTRs kept in step

Missing reverse zones are suggested for the private views' A and AAAA records (/24 for private IPv4, /32 for a public address, /48 for IPv6) and created filled with PTR records (jarl zone suggest-reverse, the Zones page). zone create --fill and zone fill-ptr add the PTRs a reverse zone lacks; a reverse zone created without a view goes to the private view using its addresses. Per zone, auto_ptr keeps the PTR records of A and AAAA records in step on every change (database version 12). Zone commands take a network.

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

internal/dnsname/dnsname_test.go

@@ -217,3 +217,35 @@ func TestReverseZones(t *testing.T) {
 		t.Errorf("ReverseZone /22: %v", err)
 	}
 }
+
+func TestPrefixFromReverse(t *testing.T) {
+	for zone, want := range map[string]string{
+		"10.0.10.in-addr.arpa.":             "10.0.10.0/24",
+		"10.in-addr.arpa":                   "10.0.0.0/8",
+		"154.144.144.139.in-addr.arpa.":     "139.144.144.154/32",
+		"d.3.f.7.3.1.0.8.2.0.a.2.ip6.arpa.": "2a02:8013:7f3d::/48",
+		"b.a.b.a.b.a.b.a.b.a.d.f.ip6.arpa.": "fdab:abab:abab::/48",
+		"0-63.1.0.10.in-addr.arpa.":         "",
+		"example.com.":                      "",
+		"256.10.in-addr.arpa.":              "",
+	} {
+		p, ok := PrefixFromReverse(zone)
+		got := ""
+		if ok {
+			got = p.String()
+		}
+		if got != want {
+			t.Errorf("PrefixFromReverse(%q) = %q, want %q", zone, got, want)
+		}
+	}
+	// Round trip with ReverseZone.
+	for _, s := range []string{"192.168.1.0/24", "2a02:8013:7f3d::/48", "fd00::/8", "10.0.0.5/32"} {
+		z, err := ReverseZone(netip.MustParsePrefix(s))
+		if err != nil {
+			t.Fatal(err)
+		}
+		if p, ok := PrefixFromReverse(z); !ok || p.String() != s {
+			t.Errorf("%s -> %s -> %v", s, z, p)
+		}
+	}
+}