Rules read as a direction

A match's zones are written "lan → wan" (or "any but wan → any", and
"lan → firewall" / "firewall → wan" in the input and output chains)
instead of "in lan · out wan" and "in not wan"; exclusions read "from
any but X". The Rules and NAT pages and hc; flags and JSON unchanged.

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

CHANGELOG.md

@@ -76,6 +76,15 @@ All notable changes to Housecarl are documented here. The format follows
 - Import: sets with `flags timeout` become dynamic sets; a DNAT of
   several ports becomes one port forward per port.
 
+### Changed
+
+- **Rules read as a direction.** A match's zones are written `lan → wan`,
+  `any but wan → any`, or with the firewall itself as the other end
+  (`lan → firewall` in input, `firewall → wan` in output), instead of
+  `in lan · out wan` and `in not wan`; exclusions read `from any but X`.
+  On the Rules and NAT pages and in `hc`; the flags and JSON stay as
+  they were.
+
 ### Fixed
 
 - `hc stats top devices` listed each device twice (once for what it

cmd/hc/main_test.go

@@ -35,9 +35,23 @@ func TestLimitAndDescribe(t *testing.T) {
 	if _, err := parseLimit("fast"); err == nil {
 		t.Error("a bad limit accepted")
 	}
-	m := model.Match{InZones: []string{"wan"}, NotSources: true, Sources: []string{"trusted"}, Services: []string{"ssh", "tcp/8080"}}
-	if got := describe(m); got != "in wan  from not trusted  ssh,tcp/8080" {
-		t.Errorf("describe: %q", got)
+	for _, c := range []struct {
+		m     model.Match
+		chain string
+		want  string
+	}{
+		{model.Match{InZones: []string{"wan"}, NotSources: true, Sources: []string{"trusted"}, Services: []string{"ssh", "tcp/8080"}}, "input",
+			"wan → firewall  from any but trusted  ssh,tcp/8080"},
+		{model.Match{InZones: []string{"wan"}, NotIn: true, Destinations: []string{"trusted_ips"}}, "forward", "any but wan → any  to trusted_ips"},
+		{model.Match{InZones: []string{"lan"}, OutZones: []string{"wan"}}, "forward", "lan → wan"},
+		{model.Match{OutZones: []string{"wan"}}, "output", "firewall → wan"},
+		{model.Match{OutZones: []string{"wan"}, Sources: []string{"10.0.0.0/8"}}, "", "any → wan  from 10.0.0.0/8"},
+		{model.Match{Sources: []string{"trusted"}}, "input", "from trusted"},
+		{model.Match{}, "forward", "everything"},
+	} {
+		if got := describe(c.m, c.chain); got != c.want {
+			t.Errorf("describe(%+v, %s) = %q, want %q", c.m, c.chain, got, c.want)
+		}
 	}
 	if got := editList([]string{"a", "b", "c"}, []string{"d"}, []string{"b"}); len(got) != 3 || got[1] != "c" || got[2] != "d" {
 		t.Errorf("editList: %v", got)

cmd/hc/rules.go

@@ -64,22 +64,40 @@ func (m *matchFlags) patch(fl *pflag.FlagSet, p patch) {
 	set("family", "family", m.family)
 }
 
-// describe sums up a match: "in lan  from trusted  ssh, dns".
-func describe(m model.Match) string {
+// describe sums up a match in a chain ("" for NAT): "lan → firewall
+// from trusted  ssh,dns". Zones are a direction; the firewall itself is
+// the other end of the input and output chains.
+func describe(m model.Match, chain string) string {
 	var parts []string
-	side := func(word string, not bool, list []string) {
-		if len(list) == 0 {
-			return
-		}
+	list := func(not bool, xs []string) string {
+		s := strings.Join(xs, ",")
 		if not {
-			word += " not"
+			return "any but " + s
 		}
-		parts = append(parts, word+" "+strings.Join(list, ","))
+		return s
+	}
+	if len(m.InZones) > 0 || len(m.OutZones) > 0 {
+		in, out := "any", "any"
+		if len(m.InZones) > 0 {
+			in = list(m.NotIn, m.InZones)
+		}
+		if len(m.OutZones) > 0 {
+			out = list(m.NotOut, m.OutZones)
+		}
+		switch chain {
+		case model.ChainInput:
+			out = "firewall"
+		case model.ChainOutput:
+			in = "firewall"
+		}
+		parts = append(parts, in+" → "+out)
+	}
+	if len(m.Sources) > 0 {
+		parts = append(parts, "from "+list(m.NotSources, m.Sources))
+	}
+	if len(m.Destinations) > 0 {
+		parts = append(parts, "to "+list(m.NotDests, m.Destinations))
 	}
-	side("in", m.NotIn, m.InZones)
-	side("out", m.NotOut, m.OutZones)
-	side("from", m.NotSources, m.Sources)
-	side("to", m.NotDests, m.Destinations)
 	if len(m.Services) > 0 {
 		parts = append(parts, strings.Join(m.Services, ","))
 	}
@@ -281,7 +299,7 @@ func ruleCmd() *cobra.Command {
 			return output(rs, func(w io.Writer) {
 				fmt.Fprintln(w, "CHAIN\tID\tMATCH\tACTION\tHITS\tCOMMENT")
 				for _, r := range rs {
-					what := describe(r.Match)
+					what := describe(r.Match, r.Chain)
 					if r.Raw != "" {
 						what = "raw: " + r.Raw
 					}
@@ -304,7 +322,7 @@ func ruleCmd() *cobra.Command {
 	cmd.AddCommand(ls)
 	cmd.AddCommand(showCmd("rules", "rule", func(w io.Writer, r model.Rule) {
 		if r.Raw == "" {
-			fmt.Fprintf(w, "ID:\t%d\nChain:\t%s\nMatch:\t%s%s\nAction:\t%s\n", r.ID, r.Chain, describe(r.Match), ruleExtras(r), r.Action)
+			fmt.Fprintf(w, "ID:\t%d\nChain:\t%s\nMatch:\t%s%s\nAction:\t%s\n", r.ID, r.Chain, describe(r.Match, r.Chain), ruleExtras(r), r.Action)
 		} else {
 			fmt.Fprintf(w, "ID:\t%d\nChain:\t%s\n", r.ID, r.Chain)
 		}
@@ -700,7 +718,7 @@ func snatCmd() *cobra.Command {
 					if to == "" {
 						to = "masquerade"
 					}
-					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\n", x.ID, describe(x.Match), to, hits(cs, fmt.Sprintf("s%d", x.ID)), x.Comment)
+					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\n", x.ID, describe(x.Match, ""), to, hits(cs, fmt.Sprintf("s%d", x.ID)), x.Comment)
 				}
 			})
 		},
@@ -780,7 +798,7 @@ func redirectCmd() *cobra.Command {
 			return output(xs, func(w io.Writer) {
 				fmt.Fprintln(w, "ID\tMATCH\tTO PORT\tHITS\tCOMMENT")
 				for _, x := range xs {
-					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\n", x.ID, describe(x.Match), orDash(x.ToPort), hits(cs, fmt.Sprintf("d%d", x.ID)), x.Comment)
+					fmt.Fprintf(w, "%d\t%s\t%s\t%s\t%s\n", x.ID, describe(x.Match, ""), orDash(x.ToPort), hits(cs, fmt.Sprintf("d%d", x.ID)), x.Comment)
 				}
 			})
 		},

internal/web/static/assets/widgets.js

@@ -98,11 +98,16 @@ export function matchEditor(m, n, opts = {}) {
 // describe sums up a match: "in lan · from trusted · ssh, dns".
 export function describe(m) {
   const parts = [];
-  const side = (word, not, list) => { if (list && list.length) parts.push(word + (not ? " not " : " ") + list.join(", ")); };
-  side("in", m.not_in, m.in_zones);
-  side("out", m.not_out, m.out_zones);
-  side("from", m.not_sources, m.sources);
-  side("to", m.not_destinations, m.destinations);
+  const list = (not, xs) => (not ? "any but " : "") + xs.join(", ");
+  // Zones are a direction, "lan → wan"; the firewall itself is the other
+  // end of the input and output chains.
+  const ins = m.in_zones || [], outs = m.out_zones || [];
+  if (ins.length || outs.length) {
+    parts.push((m.chain === "output" ? "firewall" : ins.length ? list(m.not_in, ins) : "any") + " → " +
+      (m.chain === "input" ? "firewall" : outs.length ? list(m.not_out, outs) : "any"));
+  }
+  if (m.sources && m.sources.length) parts.push("from " + list(m.not_sources, m.sources));
+  if (m.destinations && m.destinations.length) parts.push("to " + list(m.not_destinations, m.destinations));
   if (m.services && m.services.length) parts.push(m.services.join(", "));
   if (m.family) parts.push(m.family + " only");
   return parts.length ? parts.join(" · ") : "everything";