xds/rbac: use net.SplitHostPort in IP matchers to handle ip:port addresses

internal/xds/rbac/ip_matcher_test.go

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2026 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package rbac
+
+import (
+	"net"
+	"net/netip"
+	"testing"
+
+	v3corepb "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
+	"google.golang.org/grpc/peer"
+	"google.golang.org/protobuf/types/known/wrapperspb"
+)
+
+// TestRemoteIPMatcherWithTCPAddr verifies that remoteIPMatcher works correctly
+// when peer.Addr is a *net.TCPAddr, whose String() returns "ip:port" format.
+func (s) TestRemoteIPMatcherWithTCPAddr(t *testing.T) {
+	cidr := &v3corepb.CidrRange{
+		AddressPrefix: "10.0.0.0",
+		PrefixLen:     &wrapperspb.UInt32Value{Value: 8},
+	}
+	matcher, err := newRemoteIPMatcher(cidr)
+	if err != nil {
+		t.Fatalf("newRemoteIPMatcher() error: %v", err)
+	}
+
+	tests := []struct {
+		name      string
+		addr      net.Addr
+		wantMatch bool
+	}{
+		{
+			name:      "bare IP matching CIDR",
+			addr:      &addr{ipAddress: "10.0.0.5"},
+			wantMatch: true,
+		},
+		{
+			name:      "TCPAddr matching CIDR",
+			addr:      &net.TCPAddr{IP: netip.MustParseAddr("10.0.0.5").AsSlice(), Port: 8080},
+			wantMatch: true,
+		},
+		{
+			name:      "bare IP not matching CIDR",
+			addr:      &addr{ipAddress: "192.168.1.1"},
+			wantMatch: false,
+		},
+		{
+			name:      "TCPAddr not matching CIDR",
+			addr:      &net.TCPAddr{IP: netip.MustParseAddr("192.168.1.1").AsSlice(), Port: 443},
+			wantMatch: false,
+		},
+		{
+			name:      "IPv6 TCPAddr matching CIDR",
+			addr:      &net.TCPAddr{IP: netip.MustParseAddr("10.0.0.1").AsSlice(), Port: 0},
+			wantMatch: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			data := &rpcData{
+				peerInfo: &peer.Peer{Addr: tt.addr},
+			}
+			if got := matcher.match(data); got != tt.wantMatch {
+				t.Errorf("remoteIPMatcher.match() = %v, want %v (addr.String() = %q)", got, tt.wantMatch, tt.addr.String())
+			}
+		})
+	}
+}
+
+// TestLocalIPMatcherWithTCPAddr verifies that localIPMatcher works correctly
+// when localAddr is a *net.TCPAddr, whose String() returns "ip:port" format.
+func (s) TestLocalIPMatcherWithTCPAddr(t *testing.T) {
+	cidr := &v3corepb.CidrRange{
+		AddressPrefix: "172.16.0.0",
+		PrefixLen:     &wrapperspb.UInt32Value{Value: 12},
+	}
+	matcher, err := newLocalIPMatcher(cidr)
+	if err != nil {
+		t.Fatalf("newLocalIPMatcher() error: %v", err)
+	}
+
+	tests := []struct {
+		name      string
+		addr      net.Addr
+		wantMatch bool
+	}{
+		{
+			name:      "bare IP matching CIDR",
+			addr:      &addr{ipAddress: "172.16.5.1"},
+			wantMatch: true,
+		},
+		{
+			name:      "TCPAddr matching CIDR",
+			addr:      &net.TCPAddr{IP: netip.MustParseAddr("172.16.5.1").AsSlice(), Port: 9090},
+			wantMatch: true,
+		},
+		{
+			name:      "bare IP not matching CIDR",
+			addr:      &addr{ipAddress: "192.168.1.1"},
+			wantMatch: false,
+		},
+		{
+			name:      "TCPAddr not matching CIDR",
+			addr:      &net.TCPAddr{IP: netip.MustParseAddr("192.168.1.1").AsSlice(), Port: 443},
+			wantMatch: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			data := &rpcData{localAddr: tt.addr}
+			if got := matcher.match(data); got != tt.wantMatch {
+				t.Errorf("localIPMatcher.match() = %v, want %v (addr.String() = %q)", got, tt.wantMatch, tt.addr.String())
+			}
+		})
+	}
+}

internal/xds/rbac/matchers.go

@@ -19,6 +19,7 @@ package rbac
 import (
 	"errors"
 	"fmt"
+	"net"
 	"net/netip"
 	"regexp"
 
@@ -344,7 +345,12 @@ func newRemoteIPMatcher(cidrRange *v3corepb.CidrRange) (*remoteIPMatcher, error)
 }
 
 func (sim *remoteIPMatcher) match(data *rpcData) bool {
-	ip, _ := netip.ParseAddr(data.peerInfo.Addr.String())
+	addrStr := data.peerInfo.Addr.String()
+	host, _, err := net.SplitHostPort(addrStr)
+	if err != nil {
+		host = addrStr
+	}
+	ip, _ := netip.ParseAddr(host)
 	return sim.ipNet.Contains(ip)
 }
 
@@ -362,7 +368,12 @@ func newLocalIPMatcher(cidrRange *v3corepb.CidrRange) (*localIPMatcher, error) {
 }
 
 func (dim *localIPMatcher) match(data *rpcData) bool {
-	ip, _ := netip.ParseAddr(data.localAddr.String())
+	addrStr := data.localAddr.String()
+	host, _, err := net.SplitHostPort(addrStr)
+	if err != nil {
+		host = addrStr
+	}
+	ip, _ := netip.ParseAddr(host)
 	return dim.ipNet.Contains(ip)
 }