test(transport): add ipv6 coverage to integration tests

.github/workflows/go-test.yml

@@ -17,6 +17,6 @@ jobs:
   go-test:
     uses: ./.github/workflows/go-test-template.yml
     with:
-      go-versions: '["1.25.x", "1.26.x"]'
+      go-versions: '["1.24.x", "1.25.x"]'
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

go.mod

@@ -1,6 +1,6 @@
 module github.com/libp2p/go-libp2p
 
-go 1.25.7
+go 1.24.6
 
 retract v0.26.1 // Tag was applied incorrectly due to a bug in the release workflow.
 

p2p/test/transport/deadline_test.go

@@ -16,6 +16,7 @@ func TestReadWriteDeadlines(t *testing.T) {
 	sendBuf := make([]byte, 10<<20)
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			listener := tc.HostGenerator(t, TransportTestCaseOpts{})
 			defer listener.Close()
 			dialer := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})

p2p/test/transport/gating_test.go

@@ -68,6 +68,7 @@ func TestInterceptPeerDial(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -90,6 +91,7 @@ func TestInterceptAddrDial(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -115,6 +117,7 @@ func TestInterceptSecuredOutgoing(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -148,6 +151,7 @@ func TestInterceptUpgradedOutgoing(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -184,6 +188,7 @@ func TestInterceptAccept(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -232,6 +237,7 @@ func TestInterceptSecuredIncoming(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)
@@ -265,6 +271,7 @@ func TestInterceptUpgradedIncoming(t *testing.T) {
 	}
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			connGater := NewMockConnectionGater(ctrl)

p2p/test/transport/rcmgr_test.go

@@ -27,6 +27,7 @@ func TestResourceManagerIsUsed(t *testing.T) {
 		t.Run(tc.Name, func(t *testing.T) {
 			for _, testDialer := range []bool{true, false} {
 				t.Run(tc.Name+fmt.Sprintf(" test_dialer=%v", testDialer), func(t *testing.T) {
+					skipWebRTCIPv6OnWindows(t, tc.Name)
 
 					var reservedMemory, releasedMemory atomic.Int32
 					defer func() {

p2p/test/transport/transport_test.go

@@ -116,6 +116,29 @@ func selfSignedTLSConfig(t *testing.T) *tls.Config {
 	return tlsConfig
 }
 
+func skipIfNoIPv6(t *testing.T) {
+	t.Helper()
+	ln, err := net.Listen("tcp6", "[::1]:0")
+	if err != nil {
+		t.Skip("IPv6 loopback not available")
+	}
+	ln.Close()
+}
+
+// skipWebRTCIPv6OnWindows skips WebRTC IPv6 loopback integration scenarios on Windows only.
+//
+// The test listens on /ip6/::1/udp/.../webrtc-direct. Pion gathers ICE candidates on
+// link-local and global IPv6 interfaces; Windows rejects UDP sends from those addresses
+// to ::1 with wsasendto "The requested address is not valid in its context" (scope
+// mismatch), so packets never leave the stack and a loopback capture shows no IPv6 UDP.
+// Linux CI continues to run this transport case.
+func skipWebRTCIPv6OnWindows(t *testing.T, transportName string) {
+	t.Helper()
+	if transportName == "WebRTC - IP6" && runtime.GOOS == "windows" {
+		t.Skip(`WebRTC IPv6 over ::1 skipped on Windows: ICE uses non-loopback IPv6 locals; wsasendto to ::1 fails with "The requested address is not valid in its context" (scope mismatch). See PR discussion.`)
+	}
+}
+
 var transportsToTest = []TransportTestCase{
 	{
 		Name: "TCP / Noise / Yamux",
@@ -353,11 +376,108 @@ var transportsToTest = []TransportTestCase{
 			return h
 		},
 	},
+	{
+		Name: "TCP / Noise / Yamux - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			libp2pOpts = append(libp2pOpts, libp2p.Security(noise.ID, noise.New))
+			libp2pOpts = append(libp2pOpts, libp2p.Muxer(yamux.ID, yamux.DefaultTransport))
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/tcp/0"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
+	{
+		Name: "TCP / TLS / Yamux - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			libp2pOpts = append(libp2pOpts, libp2p.Security(libp2ptls.ID, libp2ptls.New))
+			libp2pOpts = append(libp2pOpts, libp2p.Muxer(yamux.ID, yamux.DefaultTransport))
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/tcp/0"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
+	{
+		Name: "WebSocket - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/tcp/0/ws"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
+	{
+		Name: "QUIC - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/udp/0/quic-v1"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
+	{
+		Name: "WebTransport - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/udp/0/quic-v1/webtransport"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
+	{
+		Name: "WebRTC - IP6",
+		HostGenerator: func(t *testing.T, opts TransportTestCaseOpts) host.Host {
+			skipIfNoIPv6(t)
+			libp2pOpts := transformOpts(opts)
+			libp2pOpts = append(libp2pOpts, libp2p.Transport(libp2pwebrtc.New))
+			if opts.NoListen {
+				libp2pOpts = append(libp2pOpts, libp2p.NoListenAddrs)
+			} else {
+				libp2pOpts = append(libp2pOpts, libp2p.ListenAddrStrings("/ip6/::1/udp/0/webrtc-direct"))
+			}
+			h, err := libp2p.New(libp2pOpts...)
+			require.NoError(t, err)
+			return h
+		},
+	},
 }
 
 func TestPing(t *testing.T) {
+
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -387,6 +507,7 @@ func TestBigPing(t *testing.T) {
 
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -515,6 +636,7 @@ func TestManyStreams(t *testing.T) {
 	const streamCount = 128
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{NoRcmgr: true})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true, NoRcmgr: true})
 			defer h1.Close()
@@ -739,6 +861,7 @@ func TestMoreStreamsThanOurLimits(t *testing.T) {
 func TestListenerStreamResets(t *testing.T) {
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -768,6 +891,7 @@ func TestListenerStreamResets(t *testing.T) {
 func TestDialerStreamResets(t *testing.T) {
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -799,6 +923,7 @@ func TestDialerStreamResets(t *testing.T) {
 func TestStreamReadDeadline(t *testing.T) {
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -853,6 +978,7 @@ func TestDiscoverPeerIDFromSecurityNegotiation(t *testing.T) {
 
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			h1 := tc.HostGenerator(t, TransportTestCaseOpts{})
 			h2 := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer h1.Close()
@@ -897,6 +1023,7 @@ func TestCloseConnWhenBlocked(t *testing.T) {
 			continue
 		}
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
 			mockRcmgr := mocknetwork.NewMockResourceManager(ctrl)
@@ -977,6 +1104,7 @@ func TestConnDroppedWhenBlocked(t *testing.T) {
 func TestConnClosedWhenRemoteCloses(t *testing.T) {
 	for _, tc := range transportsToTest {
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			server := tc.HostGenerator(t, TransportTestCaseOpts{})
 			client := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer server.Close()
@@ -1017,6 +1145,7 @@ func TestErrorCodes(t *testing.T) {
 			continue
 		}
 		t.Run(tc.Name, func(t *testing.T) {
+			skipWebRTCIPv6OnWindows(t, tc.Name)
 			server := tc.HostGenerator(t, TransportTestCaseOpts{})
 			client := tc.HostGenerator(t, TransportTestCaseOpts{NoListen: true})
 			defer server.Close()

test-plans/go.mod

@@ -1,6 +1,6 @@
 module github.com/libp2p/go-libp2p/test-plans/m/v2
 
-go 1.25.7
+go 1.24.6
 
 require (
 	github.com/go-redis/redis/v8 v8.11.5