Merge remote-tracking branch 'origin/main' into benvin/nft-decodable

# Conflicts: # internal/nftables/compiler_test.go
Count limiter expansion after table-family filtering
2026-10-10 01:10:37 +11:00 · 2026-10-09 23:52:02 +11:00 · 2026-10-09 23:48:53 +11:00 · 2026-10-09 23:48:53 +11:00 · 2026-10-09 23:39:23 +11:00
3 changed files with 533 additions and 109 deletions
@@ -67,10 +67,107 @@ func (c *Compiler) Compile() (*FirewallState, error) {
 	}
 	c.compileMSSClamp(state)
 	limitLogs(state, c.cfg.Settings.LogLimit)
+	if err := familyGuards(state, c.cfg.Settings.AddressFamily); err != nil {
+		return nil, err
+	}

 	return state, nil
 }

+// familyGuards leaves each rule at most one meta nfproto guard, ahead of its first network-header
+// payload as nft emits it; nft list cannot decode repeated or conflicting guards. Rules are built per
+// family, so a conflict is a compiler bug and fails the compile. An ip/ip6 table is its own guard:
+// guards go and other-family rules are dropped.
+func familyGuards(state *FirewallState, family config.AddressFamily) error {
+	table := tableFamily(family)
+	for chain, rules := range state.Rules {
+		var out []ManagedRule
+		for _, r := range rules {
+			fam, ok := guardFamily(r.Exprs)
+			if !ok {
+				return fmt.Errorf("%s %s: conflicting address families", chain, r.Tag)
+			}
+			if table != 0 && fam != 0 && fam != table {
+				continue
+			}
+			r.Exprs = normalizeGuards(r.Exprs, fam, table != 0)
+			out = append(out, r)
+		}
+		state.Rules[chain] = out
+	}
+	return nil
+}
+
+// tableFamily is the NFPROTO an ip/ip6 table is restricted to, 0 for inet.
+func tableFamily(family config.AddressFamily) byte {
+	return map[config.AddressFamily]byte{config.FamilyIP: unix.NFPROTO_IPV4, config.FamilyIP6: unix.NFPROTO_IPV6}[family]
+}
+
+// guardFamily is the family exprs' nfproto guards require (0: none); ok is false when they conflict.
+func guardFamily(exprs []expr.Any) (fam byte, ok bool) {
+	for i := range exprs {
+		if p := nfprotoGuard(exprs, i); p != 0 {
+			if fam != 0 && p != fam {
+				return 0, false
+			}
+			fam = p
+		}
+	}
+	return fam, true
+}
+
+// famsAgree reports whether families (0: any) can all hold for one packet.
+func famsAgree(fams ...byte) bool {
+	var f byte
+	for _, p := range fams {
+		if p != 0 && f != 0 && p != f {
+			return false
+		}
+		if p != 0 {
+			f = p
+		}
+	}
+	return true
+}
+
+func normalizeGuards(in []expr.Any, fam byte, strip bool) []expr.Any {
+	at := -1
+	out := make([]expr.Any, 0, len(in))
+	for i := 0; i < len(in); i++ {
+		if nfprotoGuard(in, i) != 0 {
+			if at < 0 {
+				at = len(out)
+			}
+			i++
+			continue
+		}
+		out = append(out, in[i])
+	}
+	if fam == 0 || strip {
+		return out
+	}
+	if l3 := slices.IndexFunc(out, func(e expr.Any) bool {
+		p, ok := e.(*expr.Payload)
+		return ok && p.Base == expr.PayloadBaseNetworkHeader
+	}); l3 >= 0 && l3 < at {
+		at = l3
+	}
+	return slices.Insert(out, at, matchNFProto(fam)...)
+}
+
+// nfprotoGuard is the family a meta nfproto == match at in[i] guards for, else 0.
+func nfprotoGuard(in []expr.Any, i int) byte {
+	m, ok := in[i].(*expr.Meta)
+	if !ok || m.Key != expr.MetaKeyNFPROTO || i+1 >= len(in) {
+		return 0
+	}
+	c, ok := in[i+1].(*expr.Cmp)
+	if !ok || c.Op != expr.CmpOpEq || c.Register != m.Register || len(c.Data) != 1 {
+		return 0
+	}
+	return c.Data[0]
+}
+
 // limitLogs puts a limit in front of every log expression. A limit stops the
 // whole rule, so like shorewall's separate LOG rule, a log followed by an action
 // splits into a limited log-only rule and the same rule without the log. A
@@ -343,7 +440,7 @@ func (c *Compiler) compileConntrack(state *FirewallState) error {
 func (c *Compiler) compileConntrackPair(state *FirewallState, tag, chain string, ct config.ConntrackRule,
 	srcZone, srcAddr, dstZone, dstAddr string) error {
 	if _, ok := c.cfg.Zones[dstZone]; ok && chain == "raw_prerouting" &&
-		(dstAddr == "" || strings.HasPrefix(dstAddr, "!")) {
+		!narrows(dstAddr) {
 		return fmt.Errorf("conntrack DEST zone %q needs an address in prerouting", dstZone)
 	}
 	srcIfaces, dstIfaces := c.resolveZone(srcZone, srcAddr), []zoneMatch{{}}
@@ -365,6 +462,9 @@ func (c *Compiler) compileConntrackPair(state *FirewallState, tag, chain string,
 			}
 			for _, m := range matches {
 				exprs := m.exprs
+				if _, ok := guardFamily(exprs); !ok {
+					continue
+				}
 				switch ct.Action {
 				case config.ConntrackNoTrack:
 					exprs = append(exprs, &expr.Notrack{})
@@ -408,7 +508,7 @@ func (c *Compiler) compileRules(state *FirewallState) error {
 				return fmt.Errorf("rule[%d]: %w", i, err)
 			}
 			if len(matches)*c.specCount(rule.Source, rule.Dest, rule.OrigDest, fwZone, rule.Action) > 1 {
-				return fmt.Errorf("rule[%d]: ratelimit/connlimit cannot be combined with proto, port, zone or address lists (each expanded rule would get its own limiter)", i)
+				return fmt.Errorf("rule[%d]: ratelimit/connlimit cannot be combined with proto, port, zone or address lists, or with a negated address in an inet table (it expands to one rule per family); each expanded rule would get its own limiter", i)
 			}
 		}

@@ -586,19 +686,39 @@ func (c *Compiler) compileDNATAccept(state *FirewallState, tag, srcZone, srcAddr
 	return nil
 }

-// specCount is how many zone/address combinations compileOneRule expands src and dst into.
+// specCount is how many rules compileOneRule emits for src and dst once familyGuards has dropped
+// cross-family address combinations and those outside an ip/ip6 table's family.
 func (c *Compiler) specCount(srcSpec, dstSpec, origDest, fwZone string, action config.RuleAction) int {
+	table := tableFamily(c.cfg.Settings.AddressFamily)
+	count := func(addrs ...string) int {
+		n := 0
+		var walk func(i int, fams []byte)
+		walk = func(i int, fams []byte) {
+			if !famsAgree(fams...) {
+				return
+			}
+			if i == len(addrs) {
+				n++
+				return
+			}
+			for _, a := range splitAddrs(addrs[i]) {
+				walk(i+1, append(fams, addrFamily(a)))
+			}
+		}
+		walk(0, []byte{table})
+		return n
+	}
 	n := 0
 	if action == config.RuleDNAT || action == config.RuleRedirect {
 		for _, src := range c.dnatSourceSpecs(srcSpec, fwZone) {
-			n += len(splitAddrs(src.Addr))
+			n += count(src.Addr, origDest)
 		}
-		return n * len(splitAddrs(origDest))
+		return n
 	}
 	for _, p := range c.zonePairs(srcSpec, dstSpec, fwZone) {
-		n += len(splitAddrs(p[0].Addr)) * len(splitAddrs(p[1].Addr))
+		n += count(p[0].Addr, p[1].Addr, origDest)
 	}
-	return n * len(splitAddrs(origDest))
+	return n
 }

 // zonePairs is the src/dst zone expansion of a non-DNAT rule, with fw added beside all/any.
@@ -664,12 +784,33 @@ func isZoneExclusion(spec string) bool {
 	return ok && (base == "all" || base == "any")
 }

-// splitAddrs yields one alternative per listed address; a negated list stays one AND-ed match.
+// splitAddrs yields one alternative per listed address. A negated list ("everything except") becomes
+// one AND-ed match per family: the family's negations, or the bare family (a /0) when it has none.
 func splitAddrs(addr string) []string {
-	if addr == "" || strings.HasPrefix(addr, "!") {
-		return []string{addr}
+	if addr == "" {
+		return []string{""}
 	}
-	return strings.Split(addr, ",")
+	if !strings.HasPrefix(addr, "!") {
+		return strings.Split(addr, ",")
+	}
+	v4, v6 := splitFamily(strings.Split(addr[1:], ","))
+	out := []string{"0.0.0.0/0", "::/0"}
+	if len(v4) > 0 {
+		out[0] = "!" + strings.Join(v4, ",")
+	}
+	if len(v6) > 0 {
+		out[1] = "!" + strings.Join(v6, ",")
+	}
+	return out
+}
+
+// narrows reports whether a splitAddrs alternative restricts addresses within its family.
+func narrows(addr string) bool {
+	if addr == "" || strings.HasPrefix(addr, "!") {
+		return false
+	}
+	p, err := parsePrefix(addr)
+	return err != nil || p.Bits() > 0
 }

 func (c *Compiler) compileZonePair(state *FirewallState, tag, srcZone, srcAddr, dstZone, dstAddr, origDest, proto string,
@@ -690,7 +831,7 @@ func (c *Compiler) compileZonePair(state *FirewallState, tag, srcZone, srcAddr,
 				return err
 			}
 			if origDest != "" {
-				od, err := matchOrigDest(origDest)
+				od, err := matchDestCIDR(origDest)
 				if err != nil {
 					return fmt.Errorf("origdest: %w", err)
 				}
@@ -701,6 +842,9 @@ func (c *Compiler) compileZonePair(state *FirewallState, tag, srcZone, srcAddr,

 			for _, m := range matches {
 				exprs := m.exprs
+				if _, ok := guardFamily(exprs); !ok {
+					continue
+				}

 				if section != "" && section != config.SectionAll {
 					exprs = append(exprs, matchSection(section)...)
@@ -750,7 +894,7 @@ func (c *Compiler) compileDNATRule(state *FirewallState, tag, srcZone, srcAddr,
 	var odExprs []expr.Any
 	if origDest != "" {
 		var err error
-		if odExprs, err = matchOrigDest(origDest); err != nil {
+		if odExprs, err = matchDestCIDR(origDest); err != nil {
 			return fmt.Errorf("origdest: %w", err)
 		}
 	}
@@ -764,6 +908,10 @@ func (c *Compiler) compileDNATRule(state *FirewallState, tag, srcZone, srcAddr,
 	if ip == nil {
 		return fmt.Errorf("invalid DNAT address %q", dnatAddr)
 	}
+	natFam := byte(0)
+	if action != config.RuleRedirect {
+		natFam = addrFamily(dnatAddr)
+	}

 	for _, srcIface := range srcIfaces {
 		zm, err := zoneMatchExprs(srcIface, true)
@@ -781,6 +929,9 @@ func (c *Compiler) compileDNATRule(state *FirewallState, tag, srcZone, srcAddr,
 				exprs = append(exprs, src...)
 			}
 			exprs = append(exprs, odExprs...)
+			if f, ok := guardFamily(exprs); !ok || !famsAgree(f, natFam) {
+				continue
+			}

 			exprs = append(exprs, m.exprs...)

@@ -881,7 +1032,7 @@ func (c *Compiler) compilePolicies(state *FirewallState) error {

 				for _, si := range srcIfaces {
 					for _, di := range dstIfaces {
-						if sz == dz && intraZoneSkip(si, di) {
+						if sz == dz && intraZoneSkip(si, di) || chain != "input" && !famsAgree(matchFamily(si), matchFamily(di)) {
 							continue
 						}
 						exprs, err := zonePairExprs(si, di, chain)
@@ -978,25 +1129,27 @@ func (c *Compiler) compileSNAT(state *FirewallState) error {
 	for i, snat := range c.cfg.SNAT {
 		tag := fmt.Sprintf("snat:%d", i)

-		var exprs []expr.Any
-
 		destIface, _ := splitZoneSpec(snat.Dest)
-		exprs = append(exprs, matchIfaceName(false, destIface)...)
-
-		if snat.Source != "" {
-			srcExprs, err := matchSourceCIDR(snat.Source)
-			if err != nil {
-				return fmt.Errorf("snat[%d]: %w", i, err)
+		var heads [][]expr.Any
+		for _, src := range splitAddrs(snat.Source) {
+			head := matchIfaceName(false, destIface)
+			if src != "" {
+				srcExprs, err := matchSourceCIDR(src)
+				if err != nil {
+					return fmt.Errorf("snat[%d]: %w", i, err)
+				}
+				head = append(head, srcExprs...)
+			}
+			if snat.Action != config.SNATAddress || famsAgree(addrFamily(src), addrFamily(snat.Address)) {
+				heads = append(heads, head)
 			}
-			exprs = append(exprs, srcExprs...)
 		}

 		matches, err := l4Matches(snat.Proto, snat.DPort, snat.SPort)
 		if err != nil {
 			return fmt.Errorf("snat[%d]: %w", i, err)
 		}
-		head := exprs
-		exprs = nil
+		var exprs []expr.Any

 		if snat.Mark != "" {
 			exprs = append(exprs, matchMark(snat.Mark)...)
@@ -1042,12 +1195,14 @@ func (c *Compiler) compileSNAT(state *FirewallState) error {
 			}
 		}

-		for _, m := range matches {
-			state.Rules["postrouting"] = append(state.Rules["postrouting"], ManagedRule{
-				Chain: "postrouting",
-				Exprs: append(append(append([]expr.Any{}, head...), m.exprs...), exprs...),
-				Tag:   tag,
-			})
+		for _, head := range heads {
+			for _, m := range matches {
+				state.Rules["postrouting"] = append(state.Rules["postrouting"], ManagedRule{
+					Chain: "postrouting",
+					Exprs: slices.Concat(head, m.exprs, exprs),
+					Tag:   tag,
+				})
+			}
 		}
 	}

@@ -1342,7 +1497,7 @@ func (c *Compiler) resolveZone(zone, addr string) []zoneMatch {
 	if len(out) > 0 || hasHosts {
 		return out
 	}
-	if addr != "" && !strings.HasPrefix(addr, "!") {
+	if narrows(addr) {
 		return []zoneMatch{{}}
 	}
 	if !c.warned[zone] {
@@ -1736,6 +1891,7 @@ func matchTCPFlags(flags, mask byte) []expr.Any {
 func matchSmurfDrop(iface string) []expr.Any {
 	var exprs []expr.Any
 	exprs = append(exprs, matchIfaceName(true, iface)...)
+	exprs = append(exprs, matchNFProto(unix.NFPROTO_IPV4)...)
 	exprs = append(exprs,
 		&expr.Payload{DestRegister: 1, Base: expr.PayloadBaseNetworkHeader, Offset: 12, Len: 4},
 		&expr.Bitwise{
@@ -1896,32 +2052,35 @@ func parseSPortOrRange(s string) ([]expr.Any, error) {
 }

 func matchSourceCIDR(cidr string) ([]expr.Any, error) {
-	return matchAddrCIDR(cidr, true)
+	return matchGuardedCIDR(cidr, true)
 }

 func matchDestCIDR(cidr string) ([]expr.Any, error) {
-	return matchAddrCIDR(cidr, false)
+	return matchGuardedCIDR(cidr, false)
 }

-// matchOrigDest guards the daddr match with the address's nfproto so it is family-correct in the inet table.
-func matchOrigDest(addr string) ([]expr.Any, error) {
-	var proto byte
-	for i, a := range strings.Split(strings.TrimPrefix(addr, "!"), ",") {
-		a, _, _ = strings.Cut(a, "/")
-		p := byte(unix.NFPROTO_IPV6)
-		if ip := net.ParseIP(a); ip != nil && ip.To4() != nil {
-			p = unix.NFPROTO_IPV4
-		}
-		if i > 0 && p != proto {
-			return nil, fmt.Errorf("%q mixes IPv4 and IPv6 addresses", addr)
-		}
-		proto = p
+// matchGuardedCIDR guards a single-family splitAddrs alternative with its nfproto; a /0 is the guard alone.
+func matchGuardedCIDR(cidr string, isSrc bool) ([]expr.Any, error) {
+	if !narrows(cidr) && !strings.HasPrefix(cidr, "!") {
+		return matchNFProto(addrFamily(cidr)), nil
 	}
-	dst, err := matchDestCIDR(addr)
+	e, err := matchAddrCIDR(cidr, isSrc)
 	if err != nil {
 		return nil, err
 	}
-	return append(matchNFProto(proto), dst...), nil
+	return append(matchNFProto(addrFamily(cidr)), e...), nil
+}
+
+// addrFamily is the NFPROTO of a single-family splitAddrs alternative, 0 for none; unparsable is IPv6.
+func addrFamily(list string) byte {
+	if list == "" {
+		return 0
+	}
+	a, _, _ := strings.Cut(strings.TrimPrefix(list, "!"), ",")
+	if p, err := parsePrefix(a); err == nil && p.Addr().Is4() {
+		return unix.NFPROTO_IPV4
+	}
+	return unix.NFPROTO_IPV6
 }

 func matchNFProto(proto byte) []expr.Any {
@@ -210,7 +210,7 @@ func TestMatchSourceCIDR_IPv6(t *testing.T) {
 	}

 	for _, tt := range tests {
-		exprs, err := matchSourceCIDR(tt.input)
+		exprs, err := matchAddrCIDR(tt.input, true)
 		if tt.wantErr {
 			if err == nil {
 				t.Errorf("matchSourceCIDR(%q) should fail", tt.input)
@@ -241,7 +241,7 @@ func TestMatchDestCIDR_IPv6(t *testing.T) {
 	}

 	for _, tt := range tests {
-		exprs, err := matchDestCIDR(tt.input)
+		exprs, err := matchAddrCIDR(tt.input, false)
 		if tt.wantErr {
 			if err == nil {
 				t.Errorf("matchDestCIDR(%q) should fail", tt.input)
@@ -961,7 +961,7 @@ func TestCompile_RateLimit(t *testing.T) {
 }

 func TestNegatedAddress(t *testing.T) {
-	exprs, err := matchSourceCIDR("!192.168.1.0/24")
+	exprs, err := matchAddrCIDR("!192.168.1.0/24", true)
 	if err != nil {
 		t.Fatalf("matchSourceCIDR(!192.168.1.0/24) error: %v", err)
 	}
@@ -973,7 +973,7 @@ func TestNegatedAddress(t *testing.T) {
 		t.Errorf("negated address should use CmpOpNeq, got %v", cmp.Op)
 	}

-	exprs, err = matchDestCIDR("!10.0.0.1")
+	exprs, err = matchAddrCIDR("!10.0.0.1", false)
 	if err != nil {
 		t.Fatalf("matchDestCIDR(!10.0.0.1) error: %v", err)
 	}
@@ -1976,57 +1976,57 @@ func TestCompile_CommaZoneLists(t *testing.T) {
 		{
 			name: "address list after colon belongs to one zone",
 			rule: config.Rule{Action: config.RuleAccept, Source: "lan", Dest: "net:192.0.2.1,198.51.100.1"},
-			want: map[string][]string{"forward": {"iif=eth1 oif=eth0 daddr=192.0.2.1", "iif=eth1 oif=eth0 daddr=198.51.100.1"}},
+			want: map[string][]string{"forward": {"iif=eth1 oif=eth0 ip4 daddr=192.0.2.1", "iif=eth1 oif=eth0 ip4 daddr=198.51.100.1"}},
 		},
 		{
 			name: "zone:address inside a list",
 			rule: config.Rule{Action: config.RuleAccept, Source: "lan,svr:203.0.113.7", Dest: "fw"},
-			want: map[string][]string{"input": {"iif=eth1", "iif=eth2 saddr=203.0.113.7"}},
+			want: map[string][]string{"input": {"iif=eth1", "iif=eth2 ip4 saddr=203.0.113.7"}},
 		},
 		{
 			name: "dnat source list",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net,lan", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
 			want: map[string][]string{"prerouting": {"iif=eth0", "iif=eth1"},
-				"forward": {"iif=eth0 oif=eth2 daddr=192.0.2.10", "iif=eth1 oif=eth2 daddr=192.0.2.10"}},
+				"forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth1 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat source list skips the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net,svr", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
-			want: map[string][]string{"prerouting": {"iif=eth0"}, "forward": {"iif=eth0 oif=eth2 daddr=192.0.2.10"}},
+			want: map[string][]string{"prerouting": {"iif=eth0"}, "forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat lone source zone may equal the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "svr", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
-			want: map[string][]string{"prerouting": {"iif=eth2"}, "forward": {"iif=eth2 oif=eth2 daddr=192.0.2.10"}},
+			want: map[string][]string{"prerouting": {"iif=eth2"}, "forward": {"iif=eth2 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat exclusion source skips the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "all!fw,anycast", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
 			want: map[string][]string{"prerouting": {"iif=eth1", "iif=eth0"},
-				"forward": {"iif=eth1 oif=eth2 daddr=192.0.2.10", "iif=eth0 oif=eth2 daddr=192.0.2.10"}},
+				"forward": {"iif=eth1 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth0 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat intrazone exclusion source keeps the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "all+!fw,anycast,lan", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
 			want: map[string][]string{"prerouting": {"iif=eth0", "iif=eth2"},
-				"forward": {"iif=eth0 oif=eth2 daddr=192.0.2.10", "iif=eth2 oif=eth2 daddr=192.0.2.10"}},
+				"forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth2 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat all source expands per zone and skips fw and the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "all", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
 			want: map[string][]string{"prerouting": {"iif=eth3", "iif=eth1", "iif=eth0"},
-				"forward": {"iif=eth3 oif=eth2 daddr=192.0.2.10", "iif=eth1 oif=eth2 daddr=192.0.2.10", "iif=eth0 oif=eth2 daddr=192.0.2.10"}},
+				"forward": {"iif=eth3 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth1 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth0 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat any+ source keeps the target zone",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "any+", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
 			want: map[string][]string{"prerouting": {"iif=eth3", "iif=eth1", "iif=eth0", "iif=eth2"},
-				"forward": {"iif=eth3 oif=eth2 daddr=192.0.2.10", "iif=eth1 oif=eth2 daddr=192.0.2.10", "iif=eth0 oif=eth2 daddr=192.0.2.10", "iif=eth2 oif=eth2 daddr=192.0.2.10"}},
+				"forward": {"iif=eth3 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth1 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth0 oif=eth2 ip4 daddr=192.0.2.10", "iif=eth2 oif=eth2 ip4 daddr=192.0.2.10"}},
 		},
 		{
 			name: "dnat to fw accepts in input",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net", Dest: "fw:192.0.2.1", Proto: "tcp", DPort: config.PortSpec{"80"}},
-			want: map[string][]string{"prerouting": {"iif=eth0"}, "input": {"iif=eth0 daddr=192.0.2.1"}},
+			want: map[string][]string{"prerouting": {"iif=eth0"}, "input": {"iif=eth0 ip4 daddr=192.0.2.1"}},
 		},
 		{
 			name: "redirect accepts in input without daddr",
@@ -2036,13 +2036,13 @@ func TestCompile_CommaZoneLists(t *testing.T) {
 		{
 			name: "dnat source address list",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net:192.0.2.5,198.51.100.5", Dest: "svr:192.0.2.10", Proto: "tcp", DPort: config.PortSpec{"80"}},
-			want: map[string][]string{"prerouting": {"iif=eth0 saddr=192.0.2.5", "iif=eth0 saddr=198.51.100.5"},
-				"forward": {"iif=eth0 oif=eth2 saddr=192.0.2.5 daddr=192.0.2.10", "iif=eth0 oif=eth2 saddr=198.51.100.5 daddr=192.0.2.10"}},
+			want: map[string][]string{"prerouting": {"iif=eth0 ip4 saddr=192.0.2.5", "iif=eth0 ip4 saddr=198.51.100.5"},
+				"forward": {"iif=eth0 oif=eth2 ip4 saddr=192.0.2.5 daddr=192.0.2.10", "iif=eth0 oif=eth2 ip4 saddr=198.51.100.5 daddr=192.0.2.10"}},
 		},
 		{
-			name: "negated address list stays one AND-ed rule",
+			name: "negated address list is one AND-ed rule per family",
 			rule: config.Rule{Action: config.RuleAccept, Source: "net:!192.0.2.5,198.51.100.5", Dest: "fw"},
-			want: map[string][]string{"input": {"iif=eth0 !saddr=192.0.2.5 !saddr=198.51.100.5"}},
+			want: map[string][]string{"input": {"iif=eth0 ip4 !saddr=192.0.2.5 !saddr=198.51.100.5", "iif=eth0 ip6"}},
 		},
 		{
 			name: "zone named like all/any keyword is a plain zone",
@@ -2057,7 +2057,7 @@ func TestCompile_CommaZoneLists(t *testing.T) {
 		{
 			name: "interface-less zone kept when address narrows it",
 			rule: config.Rule{Action: config.RuleAccept, Source: "lan", Dest: "vpn:192.0.2.1"},
-			want: map[string][]string{"forward": {"iif=eth1 daddr=192.0.2.1"}},
+			want: map[string][]string{"forward": {"iif=eth1 ip4 daddr=192.0.2.1"}},
 		},
 		{
 			name: "fw source matches dest zone oif",
@@ -2067,25 +2067,25 @@ func TestCompile_CommaZoneLists(t *testing.T) {
 		{
 			name: "fw to all has no oif",
 			rule: config.Rule{Action: config.RuleAccept, Source: "fw", Dest: "all:192.0.2.1"},
-			want: map[string][]string{"output": {"daddr=192.0.2.1"}},
+			want: map[string][]string{"output": {"ip4 daddr=192.0.2.1"}},
 		},
 		{
 			name: "dnat origdest",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net", Dest: "svr:192.0.2.17", Proto: "tcp", DPort: config.PortSpec{"80"}, OrigDest: "203.0.113.5"},
 			want: map[string][]string{"prerouting": {"iif=eth0 ip4 daddr=203.0.113.5"},
-				"forward": {"iif=eth0 oif=eth2 daddr=192.0.2.17"}},
+				"forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.17"}},
 		},
 		{
 			name: "dnat origdest list",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net", Dest: "svr:192.0.2.17", Proto: "tcp", DPort: config.PortSpec{"80"}, OrigDest: "203.0.113.5,203.0.113.6"},
 			want: map[string][]string{"prerouting": {"iif=eth0 ip4 daddr=203.0.113.5", "iif=eth0 ip4 daddr=203.0.113.6"},
-				"forward": {"iif=eth0 oif=eth2 daddr=192.0.2.17"}},
+				"forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.17"}},
 		},
 		{
 			name: "dnat negated origdest list",
 			rule: config.Rule{Action: config.RuleDNAT, Source: "net", Dest: "svr:192.0.2.17", Proto: "tcp", DPort: config.PortSpec{"80"}, OrigDest: "!203.0.113.5,203.0.113.6"},
 			want: map[string][]string{"prerouting": {"iif=eth0 ip4 !daddr=203.0.113.5 !daddr=203.0.113.6"},
-				"forward": {"iif=eth0 oif=eth2 daddr=192.0.2.17"}},
+				"forward": {"iif=eth0 oif=eth2 ip4 daddr=192.0.2.17"}},
 		},
 		{
 			name: "accept origdest",
@@ -2495,7 +2495,7 @@ func TestCompile_RejectPerProto(t *testing.T) {
 }

 func TestNegatedAddressList(t *testing.T) {
-	exprs, err := matchDestCIDR("!192.0.2.1,198.51.100.1")
+	exprs, err := matchAddrCIDR("!192.0.2.1,198.51.100.1", false)
 	if err != nil {
 		t.Fatalf("matchDestCIDR error: %v", err)
 	}
@@ -2613,25 +2613,6 @@ func TestCompile_ColonRanges(t *testing.T) {
 	}
 }

-func TestMatchOrigDest_FamilyGuard(t *testing.T) {
-	for addr, want := range map[string]byte{
-		"203.0.113.5":               unix.NFPROTO_IPV4,
-		"!203.0.113.0/24,192.0.2.1": unix.NFPROTO_IPV4,
-		"2001:db8::5":               unix.NFPROTO_IPV6,
-	} {
-		e, err := matchOrigDest(addr)
-		if err != nil {
-			t.Fatalf("%s: %v", addr, err)
-		}
-		if m, ok := e[0].(*expr.Meta); !ok || m.Key != expr.MetaKeyNFPROTO || e[1].(*expr.Cmp).Data[0] != want {
-			t.Errorf("%s: missing nfproto %d guard: %v", addr, want, e[:2])
-		}
-	}
-	if _, err := matchOrigDest("!203.0.113.5,2001:db8::5"); err == nil {
-		t.Error("mixed IPv4/IPv6 origdest: want error")
-	}
-}
-
 func TestCompile_OrigDestForwardRejected(t *testing.T) {
 	cfg := &config.Config{
 		Settings:   config.Settings{TableName: "test", AddressFamily: config.FamilyINET},
@@ -2721,7 +2702,7 @@ func TestCompile_ConntrackZones(t *testing.T) {
 		{
 			name: "source and dest addresses",
 			ct:   config.ConntrackRule{Action: config.ConntrackDrop, Source: "net:192.0.2.1,198.51.100.1", Dest: "fw:203.0.113.1"},
-			want: map[string][]string{"raw_prerouting": {"iif=eth0 saddr=192.0.2.1 daddr=203.0.113.1", "iif=eth0 saddr=198.51.100.1 daddr=203.0.113.1"}},
+			want: map[string][]string{"raw_prerouting": {"iif=eth0 ip4 saddr=192.0.2.1 daddr=203.0.113.1", "iif=eth0 ip4 saddr=198.51.100.1 daddr=203.0.113.1"}},
 		},
 		{
 			name: "fw source goes to raw_output with dest oif",
@@ -2731,7 +2712,7 @@ func TestCompile_ConntrackZones(t *testing.T) {
 		{
 			name: "all matches no interface",
 			ct:   config.ConntrackRule{Action: config.ConntrackNoTrack, Source: "all", Dest: "fw:192.0.2.53"},
-			want: map[string][]string{"raw_prerouting": {"daddr=192.0.2.53"}},
+			want: map[string][]string{"raw_prerouting": {"ip4 daddr=192.0.2.53"}},
 		},
 		{
 			name: "interface-less zone fails closed",
@@ -2789,9 +2770,9 @@ func TestCompile_ConntrackZones(t *testing.T) {
 			want: map[string][]string{"raw_output": {"oif=eth1"}},
 		},
 		{
-			name: "negated addresses stay one AND-ed match",
+			name: "negated addresses are one AND-ed match per family",
 			ct:   config.ConntrackRule{Action: config.ConntrackDrop, Source: "net:!192.0.2.1,198.51.100.1"},
-			want: map[string][]string{"raw_prerouting": {"iif=eth0 !saddr=192.0.2.1 !saddr=198.51.100.1"}},
+			want: map[string][]string{"raw_prerouting": {"iif=eth0 ip4 !saddr=192.0.2.1 !saddr=198.51.100.1", "iif=eth0 ip6"}},
 		},
 		{
 			name: "sport",
@@ -2811,7 +2792,7 @@ func TestCompile_ConntrackZones(t *testing.T) {
 		{
 			name: "fw dest zone with address matches daddr",
 			ct:   config.ConntrackRule{Action: config.ConntrackNoTrack, Source: "net", Dest: "fw:192.0.2.1"},
-			want: map[string][]string{"raw_prerouting": {"iif=eth0 daddr=192.0.2.1"}},
+			want: map[string][]string{"raw_prerouting": {"iif=eth0 ip4 daddr=192.0.2.1"}},
 		},
 		{
 			name: "unknown zone fails closed",
@@ -2866,7 +2847,7 @@ func TestCompile_ConntrackZones(t *testing.T) {
 		{
 			name: "dest zone with address matches daddr",
 			ct:   config.ConntrackRule{Action: config.ConntrackNoTrack, Source: "net", Dest: "lan:203.0.113.10"},
-			want: map[string][]string{"raw_prerouting": {"iif=eth0 daddr=203.0.113.10"}},
+			want: map[string][]string{"raw_prerouting": {"iif=eth0 ip4 daddr=203.0.113.10"}},
 		},
 	}
 	for _, tt := range tests {
@@ -2965,7 +2946,7 @@ func TestCompile_ConntrackHelperZones(t *testing.T) {
 		{
 			name: "dest zone with address in prerouting",
 			ct:   config.ConntrackRule{Source: "net", Dest: "lan:203.0.113.10", Proto: "tcp", DPort: config.PortSpec{"21"}},
-			want: map[string][]string{"helper_prerouting": {"iif=eth0 daddr=203.0.113.10"}},
+			want: map[string][]string{"helper_prerouting": {"iif=eth0 ip4 daddr=203.0.113.10"}},
 		},
 		{
 			name:    "dest zone without address is rejected in prerouting",
@@ -3031,7 +3012,7 @@ func TestCompile_AllIncludesFirewallMatches(t *testing.T) {
 		{
 			name: "all address kept on added fw rules",
 			rule: config.Rule{Action: config.RuleAccept, Source: "all:192.0.2.5", Dest: "all"},
-			want: map[string][]string{"input": {"saddr=192.0.2.5"}, "output": {"saddr=192.0.2.5"}, "forward": {"saddr=192.0.2.5"}},
+			want: map[string][]string{"input": {"ip4 saddr=192.0.2.5"}, "output": {"ip4 saddr=192.0.2.5"}, "forward": {"ip4 saddr=192.0.2.5"}},
 		},
 		{
 			name: "dnat with all source skips fw",
@@ -3615,17 +3596,17 @@ func TestCompile_DestPlusOverridesIntraZone(t *testing.T) {
 func TestCompile_HostsIntraZone(t *testing.T) {
 	state := mustCompile(t, hostsCfg(nil))
 	want := []string{
-		"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=enp2s0 ip4 daddr=198.51.100.0/24",
-		"iif=enp2s0 ip4 saddr=198.51.100.0/24 oif=wlo1 ip4 daddr=192.0.2.0/24",
+		"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=enp2s0 daddr=198.51.100.0/24",
+		"iif=enp2s0 ip4 saddr=198.51.100.0/24 oif=wlo1 daddr=192.0.2.0/24",
 	}
 	if got := describeTagged(state, "forward", "intra:lan"); !reflect.DeepEqual(got, want) {
 		t.Errorf("lan intra = %q, want %q", got, want)
 	}
 	want = []string{
-		"iif=wlo1 ip4 !saddr=192.0.2.0/24 oif=enp2s0 ip4 !daddr=198.51.100.0/24",
-		"iif=wlo1 ip6 oif=enp2s0 ip6",
-		"iif=enp2s0 ip4 !saddr=198.51.100.0/24 oif=wlo1 ip4 !daddr=192.0.2.0/24",
-		"iif=enp2s0 ip6 oif=wlo1 ip6",
+		"iif=wlo1 ip4 !saddr=192.0.2.0/24 oif=enp2s0 !daddr=198.51.100.0/24",
+		"iif=wlo1 ip6 oif=enp2s0",
+		"iif=enp2s0 ip4 !saddr=198.51.100.0/24 oif=wlo1 !daddr=192.0.2.0/24",
+		"iif=enp2s0 ip6 oif=wlo1",
 	}
 	if got := describeTagged(state, "forward", "intra:net"); !reflect.DeepEqual(got, want) {
 		t.Errorf("net intra = %q, want %q", got, want)
@@ -3638,8 +3619,8 @@ func TestCompile_HostsIntraZone(t *testing.T) {
 		t.Errorf("explicit lan lan policy must replace implicit accept, got %q", got)
 	}
 	want = []string{
-		"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=enp2s0 ip4 daddr=198.51.100.0/24",
-		"iif=enp2s0 ip4 saddr=198.51.100.0/24 oif=wlo1 ip4 daddr=192.0.2.0/24",
+		"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=enp2s0 daddr=198.51.100.0/24",
+		"iif=enp2s0 ip4 saddr=198.51.100.0/24 oif=wlo1 daddr=192.0.2.0/24",
 	}
 	if got := describeTagged(state, "forward", "policy:0"); !reflect.DeepEqual(got, want) {
 		t.Errorf("lan lan policy = %q, want %q", got, want)
@@ -3658,7 +3639,7 @@ func TestCompile_HostsRouteBack(t *testing.T) {
 	if got := describeTagged(mustCompile(t, hostsCfg(sameIface(false))), "forward", "intra:lan"); len(got) != 0 {
 		t.Errorf("same-interface hosts without routeback = %q, want none", got)
 	}
-	want := []string{"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=wlo1 ip4 daddr=192.0.2.0/24"}
+	want := []string{"iif=wlo1 ip4 saddr=192.0.2.0/24 oif=wlo1 daddr=192.0.2.0/24"}
 	if got := describeTagged(mustCompile(t, hostsCfg(sameIface(true))), "forward", "intra:lan"); !reflect.DeepEqual(got, want) {
 		t.Errorf("routeback hosts intra = %q, want %q", got, want)
 	}
@@ -3672,6 +3653,51 @@ func TestCompile_HostsRouteBack(t *testing.T) {
 	}
 }

+func TestCompile_LimitNegatedAddrPerTableFamily(t *testing.T) {
+	for _, tt := range []struct {
+		name    string
+		family  config.AddressFamily
+		source  string
+		wantErr bool
+	}{
+		{"ip v4 negation", config.FamilyIP, "net:!192.0.2.1", false},
+		{"ip v6 negation", config.FamilyIP, "net:!2001:db8::1", false},
+		{"ip mixed negation", config.FamilyIP, "net:!192.0.2.1,2001:db8::1", false},
+		{"ip6 v6 negation", config.FamilyIP6, "net:!2001:db8::1", false},
+		{"ip6 v4 negation", config.FamilyIP6, "net:!192.0.2.1", false},
+		{"inet v4 negation", config.FamilyINET, "net:!192.0.2.1", true},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := &config.Config{
+				Settings:   config.Settings{TableName: "test", AddressFamily: tt.family},
+				Zones:      map[string]config.Zone{"fw": {Type: config.ZoneFirewall}, "net": {Type: config.ZoneIP}},
+				Interfaces: []config.Interface{{Zone: "net", Interface: "eth0"}},
+				Rules:      []config.Rule{{Action: config.RuleAccept, Source: tt.source, Dest: "fw", Proto: "tcp", DPort: config.PortSpec{"22"}, RateLimit: "10/sec"}},
+				PortGroups: make(map[string]config.PortGroup),
+			}
+			state, err := NewCompiler(cfg).Compile()
+			if tt.wantErr {
+				if err == nil || !strings.Contains(err.Error(), "negated address in an inet table") {
+					t.Fatalf("Compile() error = %v, want negated-address inet error", err)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("Compile() error: %v", err)
+			}
+			n := 0
+			for _, r := range state.Rules["input"] {
+				if r.Tag == "rule:0" {
+					n++
+				}
+			}
+			if n != 1 {
+				t.Errorf("got %d rule:0 rules, want 1", n)
+			}
+		})
+	}
+}
+
 func TestCompile_WildcardParentExcludesSubZoneHosts(t *testing.T) {
 	cfg := &config.Config{
 		Settings: config.Settings{TableName: "test", AddressFamily: config.FamilyINET},
@@ -0,0 +1,239 @@
+package nftables
+
+import (
+	"os"
+	"os/exec"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/google/nftables/expr"
+	"golang.org/x/sys/unix"
+
+	"git.unkin.net/unkin/tomswall/internal/config"
+)
+
+func guardCfg(af config.AddressFamily) *config.Config {
+	return hostsCfg(func(c *config.Config) {
+		c.Settings.AddressFamily = af
+		c.Hosts[0].Addresses = append(c.Hosts[0].Addresses, "2001:db8::/64")
+		c.Hosts[0].Exclusions = []string{"192.0.2.9", "2001:db8::9"}
+		c.Interfaces[0].Options.NoSmurfs = true
+		c.Rules = append(c.Rules,
+			config.Rule{Action: config.RuleDrop, Source: "net:203.0.113.7", Dest: "lan:192.0.2.5"},
+			config.Rule{Action: config.RuleDrop, Source: "net:2001:db8:1::7", Dest: "lan:2001:db8::5"},
+			config.Rule{Action: config.RuleDrop, Source: "vpn", Dest: "net:!192.0.2.1"},
+			config.Rule{Action: config.RuleDrop, Source: "vpn", Dest: "net:!192.0.2.1,2001:db8::1"},
+			config.Rule{Action: config.RuleDrop, Source: "vpn:203.0.113.7", Dest: "net:!2001:db8::5"},
+			config.Rule{Action: config.RuleDNAT, Source: "vpn", Dest: "lan:192.0.2.10", Proto: "tcp",
+				DPort: config.PortSpec{"80"}, OrigDest: "!203.0.113.5,2001:db8::5"},
+			config.Rule{Action: config.RuleDrop, Source: "vpn:192.0.2.77,2001:db8:7::7", Dest: "fw"})
+		c.Blrules = []config.BlruleRule{{Action: config.BlruleDrop, Source: "vpn:!192.0.2.1,2001:db8::1", Dest: "fw"}}
+		c.SNAT = []config.SNATRule{
+			{Action: config.SNATMasquerade, Dest: "wlo1", Source: "!192.0.2.0/24,2001:db8::/48"},
+			{Action: config.SNATAddress, Address: "203.0.113.1", Dest: "wlo1", Source: "!192.0.2.9,2001:db8::9"},
+			{Action: config.SNATAddress, Address: "203.0.113.1", Dest: "wlo1", Source: "2001:db8::/48"},
+		}
+		c.Tunnels = []config.Tunnel{{Type: "gre", Zone: "vpn", Gateways: []string{"203.0.113.50", "2001:db8:5::1"}}}
+		c.StaticNAT = []config.StaticNAT{
+			{External: "203.0.113.60", Interface: "wlo1", Internal: "192.0.2.60"},
+			{External: "2001:db8:6::1", Interface: "wlo1", Internal: "2001:db8::60"},
+		}
+	})
+}
+
+func TestCompile_FamilyGuardsDecodable(t *testing.T) {
+	addrLen := map[config.AddressFamily]uint32{config.FamilyIP: 4, config.FamilyIP6: 16}
+	for _, af := range []config.AddressFamily{config.FamilyINET, config.FamilyIP, config.FamilyIP6} {
+		t.Run(string(af), func(t *testing.T) {
+			for chain, rules := range mustCompile(t, guardCfg(af)).Rules {
+				for _, r := range rules {
+					guards, l3 := 0, false
+					for i, e := range r.Exprs {
+						if nfprotoGuard(r.Exprs, i) != 0 {
+							guards++
+							if l3 {
+								t.Errorf("%s %s: guard after a network payload: %s", chain, r.Tag, describeRule(r))
+							}
+						}
+						if p, ok := e.(*expr.Payload); ok && p.Base == expr.PayloadBaseNetworkHeader {
+							l3 = true
+							if n := addrLen[af]; n != 0 && (p.Len == 4 || p.Len == 16) && p.Len != n {
+								t.Errorf("%s %s: other-family address in %s table: %s", chain, r.Tag, af, describeRule(r))
+							}
+						}
+					}
+					if max := map[bool]int{true: 1, false: 0}[af == config.FamilyINET]; guards > max {
+						t.Errorf("%s %s: %d family guards in %s table: %s", chain, r.Tag, guards, af, describeRule(r))
+					}
+				}
+			}
+		})
+	}
+}
+
+func TestCompile_FamilyGuardsPerFamily(t *testing.T) {
+	state := mustCompile(t, guardCfg(config.FamilyINET))
+	for _, tt := range []struct {
+		chain, tag string
+		want       []string
+	}{
+		{"forward", "rule:3", []string{
+			"iif=tun0 oif=wlo1 ip4 !daddr=192.0.2.0/24 !daddr=192.0.2.1",
+			"iif=tun0 oif=wlo1 ip4 daddr=192.0.2.9 !daddr=192.0.2.1",
+			"iif=tun0 oif=enp2s0 ip4 !daddr=198.51.100.0/24 !daddr=192.0.2.1",
+			"iif=tun0 oif=wlo1 ip6 !daddr=2001:db8::/64",
+			"iif=tun0 oif=wlo1 ip6 daddr=2001:db8::9",
+			"iif=tun0 oif=enp2s0 ip6",
+		}},
+		{"forward", "rule:4", []string{
+			"iif=tun0 oif=wlo1 ip4 !daddr=192.0.2.0/24 !daddr=192.0.2.1",
+			"iif=tun0 oif=wlo1 ip4 daddr=192.0.2.9 !daddr=192.0.2.1",
+			"iif=tun0 oif=enp2s0 ip4 !daddr=198.51.100.0/24 !daddr=192.0.2.1",
+			"iif=tun0 oif=wlo1 ip6 !daddr=2001:db8::/64 !daddr=2001:db8::1",
+			"iif=tun0 oif=wlo1 ip6 daddr=2001:db8::9 !daddr=2001:db8::1",
+			"iif=tun0 oif=enp2s0 ip6 !daddr=2001:db8::1",
+		}},
+		{"forward", "rule:5", []string{
+			"iif=tun0 oif=wlo1 ip4 !daddr=192.0.2.0/24 saddr=203.0.113.7",
+			"iif=tun0 oif=wlo1 ip4 daddr=192.0.2.9 saddr=203.0.113.7",
+			"iif=tun0 oif=enp2s0 ip4 !daddr=198.51.100.0/24 saddr=203.0.113.7",
+		}},
+		{"prerouting", "rule:6", []string{"iif=tun0 ip4 !daddr=203.0.113.5"}},
+		{"forward", "rule:6:accept", []string{"iif=tun0 oif=wlo1 ip4 daddr=192.0.2.0/24 !daddr=192.0.2.9 daddr=192.0.2.10"}},
+		{"input", "rule:7", []string{"iif=tun0 ip4 saddr=192.0.2.77", "iif=tun0 ip6 saddr=2001:db8:7::7"}},
+		{"input", "blrule:0", []string{"iif=tun0 ip4 !saddr=192.0.2.1", "iif=tun0 ip6 !saddr=2001:db8::1"}},
+		{"postrouting", "snat:0", []string{"oif=wlo1 ip4 !saddr=192.0.2.0/24", "oif=wlo1 ip6 !saddr=2001:db8::/48"}},
+		{"postrouting", "snat:1", []string{"oif=wlo1 ip4 !saddr=192.0.2.9"}},
+		{"postrouting", "snat:2", nil},
+		{"input", "tunnel:0", []string{"ip4 saddr=203.0.113.50", "ip6 saddr=2001:db8:5::1"}},
+		{"prerouting", "staticnat:dnat:0", []string{"iif=wlo1 ip4 daddr=203.0.113.60"}},
+		{"postrouting", "staticnat:snat:1", []string{"oif=wlo1 ip6 saddr=2001:db8::60"}},
+	} {
+		if got := describeTagged(state, tt.chain, tt.tag); !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("%s %s = %q, want %q", tt.chain, tt.tag, got, tt.want)
+		}
+	}
+}
+
+// TestCompile_NegatedV4DropKeepsV6 checks a single-family table keeps its family's half of a
+// negated DROP: "everything except 192.0.2.1" still drops all IPv6.
+func TestCompile_NegatedV4DropKeepsV6(t *testing.T) {
+	for af, want := range map[config.AddressFamily][]string{
+		config.FamilyIP:  {"iif=tun0 oif=wlo1 !daddr=192.0.2.0/24 !daddr=192.0.2.1", "iif=tun0 oif=wlo1 daddr=192.0.2.9 !daddr=192.0.2.1", "iif=tun0 oif=enp2s0 !daddr=198.51.100.0/24 !daddr=192.0.2.1"},
+		config.FamilyIP6: {"iif=tun0 oif=wlo1 !daddr=2001:db8::/64", "iif=tun0 oif=wlo1 daddr=2001:db8::9", "iif=tun0 oif=enp2s0"},
+	} {
+		if got := describeTagged(mustCompile(t, guardCfg(af)), "forward", "rule:3"); !reflect.DeepEqual(got, want) {
+			t.Errorf("%s rule:3 = %q, want %q", af, got, want)
+		}
+	}
+}
+
+func TestSplitAddrs(t *testing.T) {
+	for in, want := range map[string][]string{
+		"":                                       {""},
+		"192.0.2.1,2001:db8::1":                  {"192.0.2.1", "2001:db8::1"},
+		"!192.0.2.1":                             {"!192.0.2.1", "::/0"},
+		"!2001:db8::1":                           {"0.0.0.0/0", "!2001:db8::1"},
+		"!192.0.2.1,2001:db8::1,198.51.100.0/24": {"!192.0.2.1,198.51.100.0/24", "!2001:db8::1"},
+	} {
+		if got := splitAddrs(in); !reflect.DeepEqual(got, want) {
+			t.Errorf("splitAddrs(%q) = %q, want %q", in, got, want)
+		}
+	}
+}
+
+func TestMatchGuardedCIDR(t *testing.T) {
+	for in, want := range map[string]string{
+		"192.0.2.1":                  "ip4 saddr=192.0.2.1",
+		"2001:db8::/48":              "ip6 saddr=2001:db8::/48",
+		"!192.0.2.1,198.51.100.0/24": "ip4 !saddr=192.0.2.1 !saddr=198.51.100.0/24",
+		"!2001:db8::1":               "ip6 !saddr=2001:db8::1",
+		"0.0.0.0/0":                  "ip4",
+		"::/0":                       "ip6",
+	} {
+		e, err := matchSourceCIDR(in)
+		if err != nil {
+			t.Fatalf("%s: %v", in, err)
+		}
+		if got := describeRule(ManagedRule{Exprs: e}); got != want {
+			t.Errorf("matchSourceCIDR(%q) = %q, want %q", in, got, want)
+		}
+	}
+	if e, _ := matchDestCIDR("!2001:db8::5"); describeRule(ManagedRule{Exprs: e}) != "ip6 !daddr=2001:db8::5" {
+		t.Errorf("matchDestCIDR(!2001:db8::5) = %q", describeRule(ManagedRule{Exprs: e}))
+	}
+	if _, err := matchSourceCIDR("!nonsense"); err == nil {
+		t.Error("invalid negated address: want error")
+	}
+}
+
+func TestFamilyGuards(t *testing.T) {
+	v4, _ := matchSourceCIDR("192.0.2.1")
+	v6, _ := matchDestCIDR("2001:db8::1")
+	both, _ := matchDestCIDR("198.51.100.1")
+	state := func(e ...[]expr.Any) *FirewallState {
+		var r []expr.Any
+		for _, x := range e {
+			r = append(r, x...)
+		}
+		return &FirewallState{Rules: map[string][]ManagedRule{"input": {{Exprs: r, Tag: "t"}}}}
+	}
+	s := state(v4, both)
+	if err := familyGuards(s, config.FamilyINET); err != nil || describeRule(s.Rules["input"][0]) != "ip4 saddr=192.0.2.1 daddr=198.51.100.1" {
+		t.Errorf("same-family guards not merged: %v %q", err, describeRule(s.Rules["input"][0]))
+	}
+	if err := familyGuards(state(v4, v6), config.FamilyINET); err == nil || !strings.Contains(err.Error(), "conflicting") {
+		t.Errorf("conflicting guards: want error, got %v", err)
+	}
+	s = state(v6)
+	if err := familyGuards(s, config.FamilyIP); err != nil || len(s.Rules["input"]) != 0 {
+		t.Errorf("ip table must drop IPv6 rules: %v %v", err, s.Rules["input"])
+	}
+	s = state(v6)
+	if err := familyGuards(s, config.FamilyIP6); err != nil || describeRule(s.Rules["input"][0]) != "daddr=2001:db8::1" {
+		t.Errorf("ip6 table must strip the guard: %v %q", err, describeRule(s.Rules["input"][0]))
+	}
+	if !famsAgree(0, unix.NFPROTO_IPV4, 0, unix.NFPROTO_IPV4) || famsAgree(unix.NFPROTO_IPV4, 0, unix.NFPROTO_IPV6) {
+		t.Error("famsAgree")
+	}
+}
+
+// TestNetnsNftListDecodes applies each family in a fresh user+net namespace and requires
+// nft(8) to list the ruleset and a second plan to be empty. Needs unshare and nft.
+func TestNetnsNftListDecodes(t *testing.T) {
+	if af := os.Getenv("TOMSWALL_NETNS_CHILD"); af != "" {
+		netnsChild(t, config.AddressFamily(af))
+		return
+	}
+	if os.Getenv("TOMSWALL_NETNS_TEST") == "" {
+		t.Skip("set TOMSWALL_NETNS_TEST=1 to run (needs unshare and nft)")
+	}
+	for _, af := range []config.AddressFamily{config.FamilyINET, config.FamilyIP, config.FamilyIP6} {
+		cmd := exec.Command("unshare", "-rn", os.Args[0], "-test.run=^TestNetnsNftListDecodes$", "-test.v")
+		cmd.Env = append(os.Environ(), "TOMSWALL_NETNS_CHILD="+string(af))
+		if out, err := cmd.CombinedOutput(); err != nil {
+			t.Errorf("%s: %v\n%s", af, err, out)
+		}
+	}
+}
+
+func netnsChild(t *testing.T, af config.AddressFamily) {
+	e, err := NewEngine(guardCfg(af))
+	if err != nil {
+		t.Fatal(err)
+	}
+	cs, err := e.Plan()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := e.Apply(cs); err != nil {
+		t.Fatal(err)
+	}
+	if out, err := exec.Command("nft", "list", "ruleset").CombinedOutput(); err != nil {
+		t.Fatalf("nft list ruleset: %v\n%s", err, out)
+	}
+	if cs, err = e.Plan(); err != nil || len(cs.Add)+len(cs.Remove) != 0 {
+		t.Fatalf("second plan not empty: %d add, %d remove, err %v", len(cs.Add), len(cs.Remove), err)
+	}
+}
Author	SHA1	Message	Date
unkin-agent	78dbb6ad18	Merge remote-tracking branch 'origin/main' into benvin/nft-decodable ci/woodpecker/pr/pre-commit Pipeline was successful Details ci/woodpecker/pr/build Pipeline was successful Details ci/woodpecker/pr/test Pipeline was successful Details # Conflicts: # internal/nftables/compiler_test.go	2026-10-10 01:10:37 +11:00
unkin-agent	9bfdf292ad	Count limiter expansion after table-family filtering ci/woodpecker/pr/build Pipeline was successful Details ci/woodpecker/pr/test Pipeline was successful Details ci/woodpecker/pr/pre-commit Pipeline was successful Details	2026-10-09 23:52:02 +11:00
unkin-agent	bc65312647	Cover per-family expansion across rules, NAT, tunnels and blrules ci/woodpecker/pr/build Pipeline was successful Details ci/woodpecker/pr/test Pipeline was successful Details ci/woodpecker/pr/pre-commit Pipeline was successful Details	2026-10-09 23:48:53 +11:00
unkin-agent	9a65973d7f	Expand address matches per family, fail compile on conflicting guards	2026-10-09 23:48:53 +11:00
unkin-agent	42a4dab6a3	Emit one family guard per rule, none in ip/ip6 tables ci/woodpecker/pr/build Pipeline was successful Details ci/woodpecker/pr/pre-commit Pipeline was successful Details ci/woodpecker/pr/test Pipeline was successful Details	2026-10-09 23:39:23 +11:00