Expand comma zone lists in rule source and dest

internal/config/blrules.go

@@ -57,17 +57,19 @@ func (c *Config) validateBlrules() error {
 
 		if r.Source != "all" && r.Source != "any" && r.Source != "none" &&
 			!hasPrefix(r.Source, "all!") && !hasPrefix(r.Source, "any!") {
-			srcZone := zoneFromSpec(r.Source)
-			if _, ok := c.Zones[srcZone]; !ok {
-				return fmt.Errorf("blrules[%d]: source zone %q not defined", i, srcZone)
+			for _, zs := range SplitZoneList(r.Source) {
+				if _, ok := c.Zones[zs.Zone]; !ok {
+					return fmt.Errorf("blrules[%d]: source zone %q not defined", i, zs.Zone)
+				}
 			}
 		}
 
 		if r.Dest != "all" && r.Dest != "any" && r.Dest != "none" &&
 			!hasPrefix(r.Dest, "all!") && !hasPrefix(r.Dest, "any!") {
-			dstZone := zoneFromSpec(r.Dest)
-			if _, ok := c.Zones[dstZone]; !ok {
-				return fmt.Errorf("blrules[%d]: dest zone %q not defined", i, dstZone)
+			for _, zs := range SplitZoneList(r.Dest) {
+				if _, ok := c.Zones[zs.Zone]; !ok {
+					return fmt.Errorf("blrules[%d]: dest zone %q not defined", i, zs.Zone)
+				}
 			}
 		}
 	}

internal/config/config_test.go

@@ -3,6 +3,7 @@ package config
 import (
 	"os"
 	"path/filepath"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -854,6 +855,19 @@ func TestValidateRules(t *testing.T) {
 			},
 			wantErr: "source zone \"missing\" not defined",
 		},
+		{
+			name: "comma zone lists are valid",
+			rules: []Rule{
+				{Action: RuleAccept, Source: "fw,loc", Dest: "loc,net:192.0.2.1,198.51.100.1"},
+			},
+		},
+		{
+			name: "undefined zone in dest list",
+			rules: []Rule{
+				{Action: RuleAccept, Source: "loc", Dest: "net,missing"},
+			},
+			wantErr: "dest zone \"missing\" not defined",
+		},
 		{
 			name: "all keyword is valid source",
 			rules: []Rule{
@@ -1006,3 +1020,22 @@ func TestValidateSNAT(t *testing.T) {
 		})
 	}
 }
+
+func TestSplitZoneList(t *testing.T) {
+	tests := []struct {
+		in   string
+		want []ZoneSpec
+	}{
+		{"net", []ZoneSpec{{Zone: "net"}}},
+		{"fw,lan,svr", []ZoneSpec{{Zone: "fw"}, {Zone: "lan"}, {Zone: "svr"}}},
+		{"svr:192.0.2.17", []ZoneSpec{{Zone: "svr", Addr: "192.0.2.17"}}},
+		{"net:192.0.2.1,198.51.100.1", []ZoneSpec{{Zone: "net", Addr: "192.0.2.1,198.51.100.1"}}},
+		{"lan,svr:192.0.2.17", []ZoneSpec{{Zone: "lan"}, {Zone: "svr", Addr: "192.0.2.17"}}},
+		{"net:2001:db8::1", []ZoneSpec{{Zone: "net", Addr: "2001:db8::1"}}},
+	}
+	for _, tt := range tests {
+		if got := SplitZoneList(tt.in); !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("SplitZoneList(%q) = %+v, want %+v", tt.in, got, tt.want)
+		}
+	}
+}

internal/config/rules.go

@@ -1,6 +1,9 @@
 package config
 
-import "fmt"
+import (
+	"fmt"
+	"strings"
+)
 
 type RuleAction string
 
@@ -172,10 +175,9 @@ func (c *Config) validateRules() error {
 
 		if r.Source != "all" && r.Source != "any" && r.Source != "none" &&
 			!hasPrefix(r.Source, "all+") && !hasPrefix(r.Source, "all!") && !hasPrefix(r.Source, "any!") {
-			for _, srcPart := range splitZones(r.Source) {
-				srcZone := zoneFromSpec(srcPart)
-				if _, ok := c.Zones[srcZone]; !ok {
-					return fmt.Errorf("rule[%d]: source zone %q not defined", i, srcZone)
+			for _, zs := range SplitZoneList(r.Source) {
+				if _, ok := c.Zones[zs.Zone]; !ok {
+					return fmt.Errorf("rule[%d]: source zone %q not defined", i, zs.Zone)
 				}
 			}
 		}
@@ -183,10 +185,9 @@ func (c *Config) validateRules() error {
 		if r.Action != RuleDNAT && r.Action != RuleRedirect && r.Action != RuleNoNAT {
 			if r.Dest != "all" && r.Dest != "any" && r.Dest != "none" &&
 				!hasPrefix(r.Dest, "all+") && !hasPrefix(r.Dest, "all!") && !hasPrefix(r.Dest, "any!") {
-				for _, dstPart := range splitZones(r.Dest) {
-					dstZone := zoneFromSpec(dstPart)
-					if _, ok := c.Zones[dstZone]; !ok {
-						return fmt.Errorf("rule[%d]: dest zone %q not defined", i, dstZone)
+				for _, zs := range SplitZoneList(r.Dest) {
+					if _, ok := c.Zones[zs.Zone]; !ok {
+						return fmt.Errorf("rule[%d]: dest zone %q not defined", i, zs.Zone)
 					}
 				}
 			}
@@ -223,6 +224,25 @@ func (c *Config) validateRules() error {
 	return nil
 }
 
+// ZoneSpec is one zone of a SOURCE/DEST list; Addr is its comma-separated address list, if any.
+type ZoneSpec struct{ Zone, Addr string }
+
+// SplitZoneList parses "lan,svr:a,b": commas before the first colon separate zones,
+// commas after it separate addresses of the last zone (shorewall semantics).
+func SplitZoneList(spec string) []ZoneSpec {
+	zones, addr, _ := strings.Cut(spec, ":")
+	var out []ZoneSpec
+	for _, z := range strings.Split(zones, ",") {
+		if z = strings.TrimSpace(z); z != "" {
+			out = append(out, ZoneSpec{Zone: z})
+		}
+	}
+	if len(out) > 0 {
+		out[len(out)-1].Addr = addr
+	}
+	return out
+}
+
 // zoneFromSpec extracts the zone name from a zone spec like "net" or "net:192.168.1.0/24".
 func zoneFromSpec(spec string) string {
 	for i, c := range spec {

internal/nftables/compiler.go

@@ -3,6 +3,7 @@ package nftables
 import (
 	"encoding/binary"
 	"fmt"
+	"log/slog"
 	"net"
 	"strconv"
 	"strings"
@@ -285,11 +286,12 @@ func (c *Compiler) compileRules(state *FirewallState) error {
 }
 
 func (c *Compiler) applyRuleExtras(state *FirewallState, tag string, rule config.Rule) {
-	fwZone := c.cfg.FirewallZone()
-	srcZone, _ := splitZoneSpec(rule.Source)
-	dstZone, _ := splitZoneSpec(rule.Dest)
-	chain := c.selectChain(srcZone, dstZone, fwZone)
+	for chain := range state.Rules {
+		c.applyChainExtras(state, chain, tag, rule)
+	}
+}
 
+func (c *Compiler) applyChainExtras(state *FirewallState, chain, tag string, rule config.Rule) {
 	rules := state.Rules[chain]
 	for idx := len(rules) - 1; idx >= 0; idx-- {
 		if rules[idx].Tag != tag {
@@ -345,13 +347,47 @@ func (c *Compiler) compileOneRule(state *FirewallState, tag, srcSpec, dstSpec, p
 	dports, sports config.PortSpec, action config.RuleAction, logLevel string,
 	dnatDest string, fwZone string, section config.RuleSection) error {
 
-	srcZone, srcAddr := splitZoneSpec(srcSpec)
-	dstZone, dstAddr := splitZoneSpec(dstSpec)
-
-	if action == config.RuleDNAT || action == config.RuleRedirect {
-		return c.compileDNATRule(state, tag, srcSpec, dstSpec, proto, dports, sports, action, logLevel, fwZone)
+	for _, src := range zoneSpecs(srcSpec) {
+		for _, srcAddr := range splitAddrs(src.Addr) {
+			if action == config.RuleDNAT || action == config.RuleRedirect {
+				if err := c.compileDNATRule(state, tag, src.Zone, srcAddr, dstSpec, proto, dports, action, logLevel); err != nil {
+					return err
+				}
+				continue
+			}
+			for _, dst := range zoneSpecs(dstSpec) {
+				for _, dstAddr := range splitAddrs(dst.Addr) {
+					if err := c.compileZonePair(state, tag, src.Zone, srcAddr, dst.Zone, dstAddr, proto,
+						dports, sports, action, logLevel, fwZone, section); err != nil {
+						return err
+					}
+				}
+			}
+		}
 	}
+	return nil
+}
 
+// zoneSpecs expands a comma zone list; "all"/"any" forms keep their own comma (exclusion) syntax.
+func zoneSpecs(spec string) []config.ZoneSpec {
+	if strings.HasPrefix(spec, "all") || strings.HasPrefix(spec, "any") {
+		zone, addr := splitZoneSpec(spec)
+		return []config.ZoneSpec{{Zone: zone, Addr: addr}}
+	}
+	return config.SplitZoneList(spec)
+}
+
+// splitAddrs yields one alternative per listed address; a negated list stays one AND-ed match.
+func splitAddrs(addr string) []string {
+	if addr == "" || strings.HasPrefix(addr, "!") {
+		return []string{addr}
+	}
+	return strings.Split(addr, ",")
+}
+
+func (c *Compiler) compileZonePair(state *FirewallState, tag, srcZone, srcAddr, dstZone, dstAddr, proto string,
+	dports, sports config.PortSpec, action config.RuleAction, logLevel string,
+	fwZone string, section config.RuleSection) error {
 	srcIfaces := c.resolveZoneInterfaces(srcZone)
 	dstIfaces := c.resolveZoneInterfaces(dstZone)
 	chain := c.selectChain(srcZone, dstZone, fwZone)
@@ -390,10 +426,8 @@ func (c *Compiler) compileOneRule(state *FirewallState, tag, srcSpec, dstSpec, p
 	return nil
 }
 
-func (c *Compiler) compileDNATRule(state *FirewallState, tag, srcSpec, dstSpec, proto string,
-	dports, sports config.PortSpec, action config.RuleAction, logLevel, fwZone string) error {
-
-	srcZone, srcAddr := splitZoneSpec(srcSpec)
+func (c *Compiler) compileDNATRule(state *FirewallState, tag, srcZone, srcAddr, dstSpec, proto string,
+	dports config.PortSpec, action config.RuleAction, logLevel string) error {
 	chain := "prerouting"
 
 	parts := strings.SplitN(dstSpec, ":", 3)
@@ -874,10 +908,23 @@ func (c *Compiler) resolveZoneInterfaces(zone string) []string {
 		return []string{""}
 	}
 	ifaces := c.cfg.ZoneInterfaces(zone)
-	if len(ifaces) == 0 {
-		return []string{""}
+	if len(ifaces) > 0 {
+		return ifaces
 	}
-	return ifaces
+	if z, ok := c.cfg.Zones[zone]; ok && z.Type != config.ZoneFirewall && !c.zoneHasHosts(zone) {
+		slog.Warn("compiler: zone has no interfaces, skipping its rules", "zone", zone)
+		return nil
+	}
+	return []string{""}
+}
+
+func (c *Compiler) zoneHasHosts(zone string) bool {
+	for _, h := range c.cfg.Hosts {
+		if h.Zone == zone {
+			return true
+		}
+	}
+	return false
 }
 
 func (c *Compiler) expandZoneRef(ref string) []string {
@@ -1298,6 +1345,17 @@ func matchAddrCIDR(cidr string, isSrc bool) ([]expr.Any, error) {
 	if strings.HasPrefix(cidr, "!") {
 		negated = true
 		cidr = cidr[1:]
+		if strings.Contains(cidr, ",") {
+			var all []expr.Any
+			for _, a := range strings.Split(cidr, ",") {
+				e, err := matchAddrCIDR("!"+a, isSrc)
+				if err != nil {
+					return nil, err
+				}
+				all = append(all, e...)
+			}
+			return all, nil
+		}
 	}
 
 	cmpOp := expr.CmpOpEq

internal/nftables/compiler_test.go

@@ -1625,3 +1625,156 @@ func TestCompile_PortAndProtoLists(t *testing.T) {
 		})
 	}
 }
+
+// describeRule renders a rule's iif/oif/saddr/daddr matches, e.g. "iif=eth1 oif=eth2 daddr=192.0.2.1".
+func describeRule(r ManagedRule) string {
+	var parts []string
+	for i, e := range r.Exprs {
+		cmp, ok := func() (*expr.Cmp, bool) {
+			if i+1 >= len(r.Exprs) {
+				return nil, false
+			}
+			c, ok := r.Exprs[i+1].(*expr.Cmp)
+			return c, ok
+		}()
+		if !ok {
+			continue
+		}
+		switch m := e.(type) {
+		case *expr.Meta:
+			switch m.Key {
+			case expr.MetaKeyIIFNAME:
+				parts = append(parts, "iif="+strings.TrimRight(string(cmp.Data), "\x00"))
+			case expr.MetaKeyOIFNAME:
+				parts = append(parts, "oif="+strings.TrimRight(string(cmp.Data), "\x00"))
+			}
+		case *expr.Payload:
+			if m.Base == expr.PayloadBaseNetworkHeader && m.Len == 4 {
+				name := map[uint32]string{12: "saddr", 16: "daddr"}[m.Offset]
+				parts = append(parts, fmt.Sprintf("%s=%d.%d.%d.%d", name, cmp.Data[0], cmp.Data[1], cmp.Data[2], cmp.Data[3]))
+			}
+		}
+	}
+	return strings.Join(parts, " ")
+}
+
+func TestCompile_CommaZoneLists(t *testing.T) {
+	tests := []struct {
+		name string
+		rule config.Rule
+		want map[string][]string
+	}{
+		{
+			name: "fw in source list goes to output",
+			rule: config.Rule{Action: config.RuleAccept, Source: "fw,lan", Dest: "svr", Proto: "tcp", DPort: config.PortSpec{"22"}},
+			want: map[string][]string{"output": {""}, "forward": {"iif=eth1 oif=eth2"}},
+		},
+		{
+			name: "dest list with fw splits input and forward",
+			rule: config.Rule{Action: config.RuleAccept, Source: "lan", Dest: "fw,svr,net"},
+			want: map[string][]string{"input": {"iif=eth1"}, "forward": {"iif=eth1 oif=eth2", "iif=eth1 oif=eth0"}},
+		},
+		{
+			name: "zone without interfaces emits nothing",
+			rule: config.Rule{Action: config.RuleAccept, Source: "lan", Dest: "svr,dmz"},
+			want: map[string][]string{"forward": {"iif=eth1 oif=eth2"}},
+		},
+		{
+			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"}},
+		},
+		{
+			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"}},
+		},
+		{
+			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"}},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := &config.Config{
+				Settings: config.Settings{TableName: "test", AddressFamily: config.FamilyINET},
+				Zones: map[string]config.Zone{
+					"fw": {Type: config.ZoneFirewall}, "net": {Type: config.ZoneIP},
+					"lan": {Type: config.ZoneIP}, "svr": {Type: config.ZoneIP}, "dmz": {Type: config.ZoneIP},
+				},
+				Interfaces: []config.Interface{
+					{Zone: "net", Interface: "eth0"}, {Zone: "lan", Interface: "eth1"}, {Zone: "svr", Interface: "eth2"},
+				},
+				Rules:      []config.Rule{tt.rule},
+				PortGroups: make(map[string]config.PortGroup),
+			}
+			state, err := NewCompiler(cfg).Compile()
+			if err != nil {
+				t.Fatalf("Compile() error: %v", err)
+			}
+			got := map[string][]string{}
+			for chain, rules := range state.Rules {
+				for _, r := range rules {
+					if r.Tag == "rule:0" {
+						got[chain] = append(got[chain], describeRule(r))
+					}
+				}
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("rules = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestCompile_CommaZoneListExtras(t *testing.T) {
+	cfg := &config.Config{
+		Settings:   config.Settings{TableName: "test", AddressFamily: config.FamilyINET},
+		Zones:      map[string]config.Zone{"fw": {Type: config.ZoneFirewall}, "net": {Type: config.ZoneIP}, "lan": {Type: config.ZoneIP}},
+		Interfaces: []config.Interface{{Zone: "net", Interface: "eth0"}, {Zone: "lan", Interface: "eth1"}},
+		Rules:      []config.Rule{{Action: config.RuleAccept, Source: "net", Dest: "fw,lan", RateLimit: "10/sec:5"}},
+		PortGroups: make(map[string]config.PortGroup),
+	}
+	state, err := NewCompiler(cfg).Compile()
+	if err != nil {
+		t.Fatalf("Compile() error: %v", err)
+	}
+	for _, chain := range []string{"input", "forward"} {
+		found := false
+		for _, r := range state.Rules[chain] {
+			if r.Tag != "rule:0" {
+				continue
+			}
+			found = true
+			hasLimit := false
+			for _, e := range r.Exprs {
+				if _, ok := e.(*expr.Limit); ok {
+					hasLimit = true
+				}
+			}
+			if !hasLimit {
+				t.Errorf("%s rule missing Limit expression", chain)
+			}
+		}
+		if !found {
+			t.Errorf("rule:0 not found in %s chain", chain)
+		}
+	}
+}
+
+func TestNegatedAddressList(t *testing.T) {
+	exprs, err := matchDestCIDR("!192.0.2.1,198.51.100.1")
+	if err != nil {
+		t.Fatalf("matchDestCIDR error: %v", err)
+	}
+	if len(exprs) != 4 {
+		t.Fatalf("expected 4 exprs, got %d", len(exprs))
+	}
+	for _, i := range []int{1, 3} {
+		if exprs[i].(*expr.Cmp).Op != expr.CmpOpNeq {
+			t.Errorf("expr %d should be CmpOpNeq", i)
+		}
+	}
+}