Check in gVisor.

PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 550 insertions, 0 deletions

diff --git a/pkg/tcpip/transport/tcp/dual_stack_test.go b/pkg/tcpip/transport/tcp/dual_stack_test.go
new file mode 100644
index 000000000..a89af4559
--- /dev/null
+++ b/pkg/tcpip/transport/tcp/dual_stack_test.go
@@ -0,0 +1,550 @@
+// Copyright 2016 The Netstack Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tcp_test
+
+import (
+	"testing"
+	"time"
+
+	"gvisor.googlesource.com/gvisor/pkg/tcpip"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/checker"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/header"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/network/ipv4"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/seqnum"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/transport/tcp"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/transport/tcp/testing/context"
+	"gvisor.googlesource.com/gvisor/pkg/waiter"
+)
+
+func TestV4MappedConnectOnV6Only(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(true)
+
+	// Start connection attempt, it must fail.
+	err := c.EP.Connect(tcpip.FullAddress{Addr: context.TestV4MappedAddr, Port: context.TestPort})
+	if err != tcpip.ErrNoRoute {
+		t.Fatalf("Unexpected return value from Connect: %v", err)
+	}
+}
+
+func testV4Connect(t *testing.T, c *context.Context) {
+	// Start connection attempt.
+	we, ch := waiter.NewChannelEntry(nil)
+	c.WQ.EventRegister(&we, waiter.EventOut)
+	defer c.WQ.EventUnregister(&we)
+
+	err := c.EP.Connect(tcpip.FullAddress{Addr: context.TestV4MappedAddr, Port: context.TestPort})
+	if err != tcpip.ErrConnectStarted {
+		t.Fatalf("Unexpected return value from Connect: %v", err)
+	}
+
+	// Receive SYN packet.
+	b := c.GetPacket()
+	checker.IPv4(t, b,
+		checker.TCP(
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagSyn),
+		),
+	)
+
+	tcp := header.TCP(header.IPv4(b).Payload())
+	c.IRS = seqnum.Value(tcp.SequenceNumber())
+
+	iss := seqnum.Value(789)
+	c.SendPacket(nil, &context.Headers{
+		SrcPort: tcp.DestinationPort(),
+		DstPort: tcp.SourcePort(),
+		Flags:   header.TCPFlagSyn | header.TCPFlagAck,
+		SeqNum:  iss,
+		AckNum:  c.IRS.Add(1),
+		RcvWnd:  30000,
+	})
+
+	// Receive ACK packet.
+	checker.IPv4(t, c.GetPacket(),
+		checker.TCP(
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagAck),
+			checker.SeqNum(uint32(c.IRS)+1),
+			checker.AckNum(uint32(iss)+1),
+		),
+	)
+
+	// Wait for connection to be established.
+	select {
+	case <-ch:
+		err = c.EP.GetSockOpt(tcpip.ErrorOption{})
+		if err != nil {
+			t.Fatalf("Unexpected error when connecting: %v", err)
+		}
+	case <-time.After(1 * time.Second):
+		t.Fatalf("Timed out waiting for connection")
+	}
+}
+
+func TestV4MappedConnect(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Test the connection request.
+	testV4Connect(t, c)
+}
+
+func TestV4ConnectWhenBoundToWildcard(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test the connection request.
+	testV4Connect(t, c)
+}
+
+func TestV4ConnectWhenBoundToV4MappedWildcard(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to v4 mapped wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.V4MappedWildcardAddr}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test the connection request.
+	testV4Connect(t, c)
+}
+
+func TestV4ConnectWhenBoundToV4Mapped(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to v4 mapped address.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.StackV4MappedAddr}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test the connection request.
+	testV4Connect(t, c)
+}
+
+func testV6Connect(t *testing.T, c *context.Context) {
+	// Start connection attempt to IPv6 address.
+	we, ch := waiter.NewChannelEntry(nil)
+	c.WQ.EventRegister(&we, waiter.EventOut)
+	defer c.WQ.EventUnregister(&we)
+
+	err := c.EP.Connect(tcpip.FullAddress{Addr: context.TestV6Addr, Port: context.TestPort})
+	if err != tcpip.ErrConnectStarted {
+		t.Fatalf("Unexpected return value from Connect: %v", err)
+	}
+
+	// Receive SYN packet.
+	b := c.GetV6Packet()
+	checker.IPv6(t, b,
+		checker.TCP(
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagSyn),
+		),
+	)
+
+	tcp := header.TCP(header.IPv6(b).Payload())
+	c.IRS = seqnum.Value(tcp.SequenceNumber())
+
+	iss := seqnum.Value(789)
+	c.SendV6Packet(nil, &context.Headers{
+		SrcPort: tcp.DestinationPort(),
+		DstPort: tcp.SourcePort(),
+		Flags:   header.TCPFlagSyn | header.TCPFlagAck,
+		SeqNum:  iss,
+		AckNum:  c.IRS.Add(1),
+		RcvWnd:  30000,
+	})
+
+	// Receive ACK packet.
+	checker.IPv6(t, c.GetV6Packet(),
+		checker.TCP(
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagAck),
+			checker.SeqNum(uint32(c.IRS)+1),
+			checker.AckNum(uint32(iss)+1),
+		),
+	)
+
+	// Wait for connection to be established.
+	select {
+	case <-ch:
+		err = c.EP.GetSockOpt(tcpip.ErrorOption{})
+		if err != nil {
+			t.Fatalf("Unexpected error when connecting: %v", err)
+		}
+	case <-time.After(1 * time.Second):
+		t.Fatalf("Timed out waiting for connection")
+	}
+}
+
+func TestV6Connect(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Test the connection request.
+	testV6Connect(t, c)
+}
+
+func TestV6ConnectV6Only(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(true)
+
+	// Test the connection request.
+	testV6Connect(t, c)
+}
+
+func TestV6ConnectWhenBoundToWildcard(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test the connection request.
+	testV6Connect(t, c)
+}
+
+func TestV6ConnectWhenBoundToLocalAddress(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to local address.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.StackV6Addr}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test the connection request.
+	testV6Connect(t, c)
+}
+
+func TestV4RefuseOnV6Only(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(true)
+
+	// Bind to wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Start listening.
+	if err := c.EP.Listen(10); err != nil {
+		t.Fatalf("Listen failed: %v", err)
+	}
+
+	// Send a SYN request.
+	irs := seqnum.Value(789)
+	c.SendPacket(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagSyn,
+		SeqNum:  irs,
+		RcvWnd:  30000,
+	})
+
+	// Receive the RST reply.
+	checker.IPv4(t, c.GetPacket(),
+		checker.TCP(
+			checker.SrcPort(context.StackPort),
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagRst|header.TCPFlagAck),
+			checker.AckNum(uint32(irs)+1),
+		),
+	)
+}
+
+func TestV6RefuseOnBoundToV4Mapped(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind and listen.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.V4MappedWildcardAddr, Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	if err := c.EP.Listen(10); err != nil {
+		t.Fatalf("Listen failed: %v", err)
+	}
+
+	// Send a SYN request.
+	irs := seqnum.Value(789)
+	c.SendV6Packet(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagSyn,
+		SeqNum:  irs,
+		RcvWnd:  30000,
+	})
+
+	// Receive the RST reply.
+	checker.IPv6(t, c.GetV6Packet(),
+		checker.TCP(
+			checker.SrcPort(context.StackPort),
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagRst|header.TCPFlagAck),
+			checker.AckNum(uint32(irs)+1),
+		),
+	)
+}
+
+func testV4Accept(t *testing.T, c *context.Context) {
+	// Start listening.
+	if err := c.EP.Listen(10); err != nil {
+		t.Fatalf("Listen failed: %v", err)
+	}
+
+	// Send a SYN request.
+	irs := seqnum.Value(789)
+	c.SendPacket(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagSyn,
+		SeqNum:  irs,
+		RcvWnd:  30000,
+	})
+
+	// Receive the SYN-ACK reply.
+	b := c.GetPacket()
+	tcp := header.TCP(header.IPv4(b).Payload())
+	iss := seqnum.Value(tcp.SequenceNumber())
+	checker.IPv4(t, b,
+		checker.TCP(
+			checker.SrcPort(context.StackPort),
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagAck|header.TCPFlagSyn),
+			checker.AckNum(uint32(irs)+1),
+		),
+	)
+
+	// Send ACK.
+	c.SendPacket(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagAck,
+		SeqNum:  irs + 1,
+		AckNum:  iss + 1,
+		RcvWnd:  30000,
+	})
+
+	// Try to accept the connection.
+	we, ch := waiter.NewChannelEntry(nil)
+	c.WQ.EventRegister(&we, waiter.EventIn)
+	defer c.WQ.EventUnregister(&we)
+
+	nep, _, err := c.EP.Accept()
+	if err == tcpip.ErrWouldBlock {
+		// Wait for connection to be established.
+		select {
+		case <-ch:
+			nep, _, err = c.EP.Accept()
+			if err != nil {
+				t.Fatalf("Accept failed: %v", err)
+			}
+
+		case <-time.After(1 * time.Second):
+			t.Fatalf("Timed out waiting for accept")
+		}
+	}
+
+	// Make sure we get the same error when calling the original ep and the
+	// new one. This validates that v4-mapped endpoints are still able to
+	// query the V6Only flag, whereas pure v4 endpoints are not.
+	var v tcpip.V6OnlyOption
+	expected := c.EP.GetSockOpt(&v)
+	if err := nep.GetSockOpt(&v); err != expected {
+		t.Fatalf("GetSockOpt returned unexpected value: got %v, want %v", err, expected)
+	}
+
+	// Check the peer address.
+	addr, err := nep.GetRemoteAddress()
+	if err != nil {
+		t.Fatalf("GetRemoteAddress failed failed: %v", err)
+	}
+
+	if addr.Addr != context.TestAddr {
+		t.Fatalf("Unexpected remote address: got %v, want %v", addr.Addr, context.TestAddr)
+	}
+}
+
+func TestV4AcceptOnV6(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test acceptance.
+	testV4Accept(t, c)
+}
+
+func TestV4AcceptOnBoundToV4MappedWildcard(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind to v4 mapped wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.V4MappedWildcardAddr, Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test acceptance.
+	testV4Accept(t, c)
+}
+
+func TestV4AcceptOnBoundToV4Mapped(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind and listen.
+	if err := c.EP.Bind(tcpip.FullAddress{Addr: context.StackV4MappedAddr, Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test acceptance.
+	testV4Accept(t, c)
+}
+
+func TestV6AcceptOnV6(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	c.CreateV6Endpoint(false)
+
+	// Bind and listen.
+	if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	if err := c.EP.Listen(10); err != nil {
+		t.Fatalf("Listen failed: %v", err)
+	}
+
+	// Send a SYN request.
+	irs := seqnum.Value(789)
+	c.SendV6Packet(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagSyn,
+		SeqNum:  irs,
+		RcvWnd:  30000,
+	})
+
+	// Receive the SYN-ACK reply.
+	b := c.GetV6Packet()
+	tcp := header.TCP(header.IPv6(b).Payload())
+	iss := seqnum.Value(tcp.SequenceNumber())
+	checker.IPv6(t, b,
+		checker.TCP(
+			checker.SrcPort(context.StackPort),
+			checker.DstPort(context.TestPort),
+			checker.TCPFlags(header.TCPFlagAck|header.TCPFlagSyn),
+			checker.AckNum(uint32(irs)+1),
+		),
+	)
+
+	// Send ACK.
+	c.SendV6Packet(nil, &context.Headers{
+		SrcPort: context.TestPort,
+		DstPort: context.StackPort,
+		Flags:   header.TCPFlagAck,
+		SeqNum:  irs + 1,
+		AckNum:  iss + 1,
+		RcvWnd:  30000,
+	})
+
+	// Try to accept the connection.
+	we, ch := waiter.NewChannelEntry(nil)
+	c.WQ.EventRegister(&we, waiter.EventIn)
+	defer c.WQ.EventUnregister(&we)
+
+	nep, _, err := c.EP.Accept()
+	if err == tcpip.ErrWouldBlock {
+		// Wait for connection to be established.
+		select {
+		case <-ch:
+			nep, _, err = c.EP.Accept()
+			if err != nil {
+				t.Fatalf("Accept failed: %v", err)
+			}
+
+		case <-time.After(1 * time.Second):
+			t.Fatalf("Timed out waiting for accept")
+		}
+	}
+
+	// Make sure we can still query the v6 only status of the new endpoint,
+	// that is, that it is in fact a v6 socket.
+	var v tcpip.V6OnlyOption
+	if err := nep.GetSockOpt(&v); err != nil {
+		t.Fatalf("GetSockOpt failed failed: %v", err)
+	}
+
+	// Check the peer address.
+	addr, err := nep.GetRemoteAddress()
+	if err != nil {
+		t.Fatalf("GetRemoteAddress failed failed: %v", err)
+	}
+
+	if addr.Addr != context.TestV6Addr {
+		t.Fatalf("Unexpected remote address: got %v, want %v", addr.Addr, context.TestV6Addr)
+	}
+}
+
+func TestV4AcceptOnV4(t *testing.T) {
+	c := context.New(t, defaultMTU)
+	defer c.Cleanup()
+
+	// Create TCP endpoint.
+	var err *tcpip.Error
+	c.EP, err = c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, &c.WQ)
+	if err != nil {
+		t.Fatalf("NewEndpoint failed: %v", err)
+	}
+
+	// Bind to wildcard.
+	if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}, nil); err != nil {
+		t.Fatalf("Bind failed: %v", err)
+	}
+
+	// Test acceptance.
+	testV4Accept(t, c)
+}