Example #1
1
func TestPacketConnReadWriteUnicastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}

	c, err := net.ListenPacket("udp6", "[::1]:0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()
	p := ipv6.NewPacketConn(c)
	defer p.Close()

	dst, err := net.ResolveUDPAddr("udp6", c.LocalAddr().String())
	if err != nil {
		t.Fatal(err)
	}

	cm := ipv6.ControlMessage{
		TrafficClass: iana.DiffServAF11 | iana.CongestionExperienced,
		Src:          net.IPv6loopback,
	}
	cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagLoopback)
	if ifi != nil {
		cm.IfIndex = ifi.Index
	}
	wb := []byte("HELLO-R-U-THERE")

	for i, toggle := range []bool{true, false, true} {
		if err := p.SetControlMessage(cf, toggle); err != nil {
			if nettest.ProtocolNotSupported(err) {
				t.Skipf("not supported on %s", runtime.GOOS)
			}
			t.Fatal(err)
		}
		cm.HopLimit = i + 1
		if err := p.SetWriteDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, err := p.WriteTo(wb, &cm, dst); err != nil {
			t.Fatal(err)
		} else if n != len(wb) {
			t.Fatalf("got %v; want %v", n, len(wb))
		}
		rb := make([]byte, 128)
		if err := p.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, _, _, err := p.ReadFrom(rb); err != nil {
			t.Fatal(err)
		} else if !bytes.Equal(rb[:n], wb) {
			t.Fatalf("got %v; want %v", rb[:n], wb)
		}
	}
}
func TestPacketConnMulticastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %q", runtime.GOOS)
	}

	for _, tt := range packetConnMulticastSocketOptionTests {
		if tt.net == "ip4" && os.Getuid() != 0 {
			t.Log("must be root")
			continue
		}
		c, err := net.ListenPacket(tt.net+tt.proto, tt.addr)
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()
		p := ipv4.NewPacketConn(c)
		defer p.Close()

		if tt.src == nil {
			testMulticastSocketOptions(t, p, ifi, tt.grp)
		} else {
			testSourceSpecificMulticastSocketOptions(t, p, ifi, tt.grp, tt.src)
		}
	}
}
func TestRawConnMulticastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range rawConnMulticastSocketOptionTests {
		c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()
		r, err := ipv4.NewRawConn(c)
		if err != nil {
			t.Fatal(err)
		}
		defer r.Close()

		if tt.src == nil {
			testMulticastSocketOptions(t, r, ifi, tt.grp)
		} else {
			testSourceSpecificMulticastSocketOptions(t, r, ifi, tt.grp, tt.src)
		}
	}
}
func TestConnUnicastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	ln, err := net.Listen("tcp4", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer ln.Close()

	done := make(chan bool)
	go acceptor(t, ln, done)

	c, err := net.Dial("tcp4", ln.Addr().String())
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	testUnicastSocketOptions(t, ipv4.NewConn(c))

	<-done
}
func TestRawConnUnicastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	if os.Getuid() != 0 {
		t.Skip("must be root")
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %q", runtime.GOOS)
	}

	c, err := net.ListenPacket("ip4:icmp", "127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	r, err := ipv4.NewRawConn(c)
	if err != nil {
		t.Fatal(err)
	}

	testUnicastSocketOptions(t, r)
}
func TestRawConnMulticastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	if os.Getuid() != 0 {
		t.Skip("must be root")
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %q", runtime.GOOS)
	}

	c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
	if err != nil {
		t.Fatalf("net.ListenPacket failed: %v", err)
	}
	defer c.Close()

	r, err := ipv4.NewRawConn(c)
	if err != nil {
		t.Fatalf("ipv4.NewRawConn failed: %v", err)
	}

	testMulticastSocketOptions(t, r, ifi, &net.IPAddr{IP: net.IPv4(224, 0, 0, 250)}) /// see RFC 4727
}
func TestPacketConnUnicastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	m, ok := nettest.SupportsRawIPSocket()
	for _, tt := range packetConnUnicastSocketOptionTests {
		if tt.net == "ip4" && !ok {
			t.Log(m)
			continue
		}
		c, err := net.ListenPacket(tt.net+tt.proto, tt.addr)
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		testUnicastSocketOptions(t, ipv4.NewPacketConn(c))
	}
}
func TestPacketConnMulticastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	m, ok := nettest.SupportsRawIPSocket()
	for _, tt := range packetConnMulticastSocketOptionTests {
		if tt.net == "ip6" && !ok {
			t.Log(m)
			continue
		}
		c, err := net.ListenPacket(tt.net+tt.proto, tt.addr)
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()
		p := ipv6.NewPacketConn(c)
		defer p.Close()

		if tt.src == nil {
			testMulticastSocketOptions(t, p, ifi, tt.grp)
		} else {
			testSourceSpecificMulticastSocketOptions(t, p, ifi, tt.grp, tt.src)
		}
	}
}
func TestRawConnUnicastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	c, err := net.ListenPacket("ip4:icmp", "127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	r, err := ipv4.NewRawConn(c)
	if err != nil {
		t.Fatal(err)
	}

	testUnicastSocketOptions(t, r)
}
Example #10
0
func TestPacketConnReadWriteUnicastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	c, err := net.ListenPacket("udp4", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	dst, err := net.ResolveUDPAddr("udp4", c.LocalAddr().String())
	if err != nil {
		t.Fatal(err)
	}
	p := ipv4.NewPacketConn(c)
	defer p.Close()
	cf := ipv4.FlagTTL | ipv4.FlagDst | ipv4.FlagInterface
	wb := []byte("HELLO-R-U-THERE")

	for i, toggle := range []bool{true, false, true} {
		if err := p.SetControlMessage(cf, toggle); err != nil {
			if nettest.ProtocolNotSupported(err) {
				t.Logf("not supported on %s", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		}
		p.SetTTL(i + 1)
		if err := p.SetWriteDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, err := p.WriteTo(wb, nil, dst); err != nil {
			t.Fatal(err)
		} else if n != len(wb) {
			t.Fatalf("got %v; want %v", n, len(wb))
		}
		rb := make([]byte, 128)
		if err := p.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, cm, _, err := p.ReadFrom(rb); err != nil {
			t.Fatal(err)
		} else if !bytes.Equal(rb[:n], wb) {
			t.Fatalf("got %v; want %v", rb[:n], wb)
		} else {
			t.Logf("rcvd cmsg: %v", cm)
		}
	}
}
Example #11
0
func BenchmarkReadWriteIPv4UDP(b *testing.B) {
	c, dst, err := benchmarkUDPListener()
	if err != nil {
		b.Fatal(err)
	}
	defer c.Close()

	p := ipv4.NewPacketConn(c)
	defer p.Close()
	cf := ipv4.FlagTTL | ipv4.FlagInterface
	if err := p.SetControlMessage(cf, true); err != nil {
		b.Fatal(err)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)

	wb, rb := []byte("HELLO-R-U-THERE"), make([]byte, 128)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		benchmarkReadWriteIPv4UDP(b, p, wb, rb, dst, ifi)
	}
}
Example #12
0
func TestConnUnicastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	ln, err := net.Listen("tcp4", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer ln.Close()

	errc := make(chan error, 1)
	go func() {
		c, err := ln.Accept()
		if err != nil {
			errc <- err
			return
		}
		errc <- c.Close()
	}()

	c, err := net.Dial("tcp4", ln.Addr().String())
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	testUnicastSocketOptions(t, ipv4.NewConn(c))

	if err := <-errc; err != nil {
		t.Errorf("server: %v", err)
	}
}
func TestPacketConnMulticastSocketOptions(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %q", runtime.GOOS)
	}

	for _, tt := range packetConnMulticastSocketOptionTests {
		if tt.net == "ip4" && os.Getuid() != 0 {
			t.Skip("must be root")
		}
		c, err := net.ListenPacket(tt.net+tt.proto, tt.addr)
		if err != nil {
			t.Fatalf("net.ListenPacket failed: %v", err)
		}
		defer c.Close()

		testMulticastSocketOptions(t, ipv4.NewPacketConn(c), ifi, tt.gaddr)
	}
}
Example #14
0
func BenchmarkReadWriteIPv6UDP(b *testing.B) {
	if !supportsIPv6 {
		b.Skip("ipv6 is not supported")
	}

	c, dst, err := benchmarkUDPListener()
	if err != nil {
		b.Fatal(err)
	}
	defer c.Close()

	p := ipv6.NewPacketConn(c)
	cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU
	if err := p.SetControlMessage(cf, true); err != nil {
		b.Fatal(err)
	}
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagLoopback)

	wb, rb := []byte("HELLO-R-U-THERE"), make([]byte, 128)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		benchmarkReadWriteIPv6UDP(b, p, wb, rb, dst, ifi)
	}
}
Example #15
0
func TestPacketConnConcurrentReadWriteUnicastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}

	c, err := net.ListenPacket("udp6", "[::1]:0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()
	p := ipv6.NewPacketConn(c)
	defer p.Close()

	dst, err := net.ResolveUDPAddr("udp6", c.LocalAddr().String())
	if err != nil {
		t.Fatal(err)
	}

	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagLoopback)
	cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU
	wb := []byte("HELLO-R-U-THERE")

	if err := p.SetControlMessage(cf, true); err != nil { // probe before test
		if nettest.ProtocolNotSupported(err) {
			t.Skipf("not supported on %q", runtime.GOOS)
		}
		t.Fatal(err)
	}

	var wg sync.WaitGroup
	reader := func() {
		defer wg.Done()
		rb := make([]byte, 128)
		if n, cm, _, err := p.ReadFrom(rb); err != nil {
			t.Error(err)
			return
		} else if !bytes.Equal(rb[:n], wb) {
			t.Errorf("got %v; want %v", rb[:n], wb)
			return
		} else {
			t.Logf("rcvd cmsg: %v", cm)
		}
	}
	writer := func(toggle bool) {
		defer wg.Done()
		cm := ipv6.ControlMessage{
			TrafficClass: iana.DiffServAF11 | iana.CongestionExperienced,
			Src:          net.IPv6loopback,
		}
		if ifi != nil {
			cm.IfIndex = ifi.Index
		}
		if err := p.SetControlMessage(cf, toggle); err != nil {
			t.Error(err)
			return
		}
		if n, err := p.WriteTo(wb, &cm, dst); err != nil {
			t.Error(err)
			return
		} else if n != len(wb) {
			t.Errorf("got %v; want %v", n, len(wb))
			return
		}
	}

	const N = 10
	wg.Add(N)
	for i := 0; i < N; i++ {
		go reader()
	}
	wg.Add(2 * N)
	for i := 0; i < 2*N; i++ {
		go writer(i%2 != 0)
	}
	wg.Add(N)
	for i := 0; i < N; i++ {
		go reader()
	}
	wg.Wait()
}
Example #16
0
func TestPacketConnReadWriteUnicastICMP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	dst, err := net.ResolveIPAddr("ip4", "127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	p := ipv4.NewPacketConn(c)
	defer p.Close()
	cf := ipv4.FlagDst | ipv4.FlagInterface
	if runtime.GOOS != "solaris" {
		// Solaris never allows to modify ICMP properties.
		cf |= ipv4.FlagTTL
	}

	for i, toggle := range []bool{true, false, true} {
		wb, err := (&icmp.Message{
			Type: ipv4.ICMPTypeEcho, Code: 0,
			Body: &icmp.Echo{
				ID: os.Getpid() & 0xffff, Seq: i + 1,
				Data: []byte("HELLO-R-U-THERE"),
			},
		}).Marshal(nil)
		if err != nil {
			t.Fatal(err)
		}
		if err := p.SetControlMessage(cf, toggle); err != nil {
			if nettest.ProtocolNotSupported(err) {
				t.Logf("not supported on %s", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		}
		p.SetTTL(i + 1)
		if err := p.SetWriteDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, err := p.WriteTo(wb, nil, dst); err != nil {
			t.Fatal(err)
		} else if n != len(wb) {
			t.Fatalf("got %v; want %v", n, len(wb))
		}
		rb := make([]byte, 128)
	loop:
		if err := p.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, _, _, err := p.ReadFrom(rb); err != nil {
			switch runtime.GOOS {
			case "darwin": // older darwin kernels have some limitation on receiving icmp packet through raw socket
				t.Logf("not supported on %s", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		} else {
			m, err := icmp.ParseMessage(iana.ProtocolICMP, rb[:n])
			if err != nil {
				t.Fatal(err)
			}
			if runtime.GOOS == "linux" && m.Type == ipv4.ICMPTypeEcho {
				// On Linux we must handle own sent packets.
				goto loop
			}
			if m.Type != ipv4.ICMPTypeEchoReply || m.Code != 0 {
				t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv4.ICMPTypeEchoReply, 0)
			}
		}
	}
}
Example #17
0
func TestRawConnReadWriteUnicastICMP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()

	dst, err := net.ResolveIPAddr("ip4", "127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	r, err := ipv4.NewRawConn(c)
	if err != nil {
		t.Fatal(err)
	}
	defer r.Close()
	cf := ipv4.FlagTTL | ipv4.FlagDst | ipv4.FlagInterface

	for i, toggle := range []bool{true, false, true} {
		wb, err := (&icmp.Message{
			Type: ipv4.ICMPTypeEcho, Code: 0,
			Body: &icmp.Echo{
				ID: os.Getpid() & 0xffff, Seq: i + 1,
				Data: []byte("HELLO-R-U-THERE"),
			},
		}).Marshal(nil)
		if err != nil {
			t.Fatal(err)
		}
		wh := &ipv4.Header{
			Version:  ipv4.Version,
			Len:      ipv4.HeaderLen,
			TOS:      i + 1,
			TotalLen: ipv4.HeaderLen + len(wb),
			TTL:      i + 1,
			Protocol: 1,
			Dst:      dst.IP,
		}
		if err := r.SetControlMessage(cf, toggle); err != nil {
			if nettest.ProtocolNotSupported(err) {
				t.Logf("not supported on %s", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		}
		if err := r.SetWriteDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if err := r.WriteTo(wh, wb, nil); err != nil {
			t.Fatal(err)
		}
		rb := make([]byte, ipv4.HeaderLen+128)
	loop:
		if err := r.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if _, b, _, err := r.ReadFrom(rb); err != nil {
			switch runtime.GOOS {
			case "darwin": // older darwin kernels have some limitation on receiving icmp packet through raw socket
				t.Logf("not supported on %s", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		} else {
			m, err := icmp.ParseMessage(iana.ProtocolICMP, b)
			if err != nil {
				t.Fatal(err)
			}
			if runtime.GOOS == "linux" && m.Type == ipv4.ICMPTypeEcho {
				// On Linux we must handle own sent packets.
				goto loop
			}
			if m.Type != ipv4.ICMPTypeEchoReply || m.Code != 0 {
				t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv4.ICMPTypeEchoReply, 0)
			}
		}
	}
}
Example #18
0
func TestPacketConnReadWriteUnicastICMP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %q", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}
	if os.Getuid() != 0 {
		t.Skip("must be root")
	}

	c, err := net.ListenPacket("ip6:ipv6-icmp", "::1")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()
	p := ipv6.NewPacketConn(c)
	defer p.Close()

	dst, err := net.ResolveIPAddr("ip6", "::1")
	if err != nil {
		t.Fatal(err)
	}

	pshicmp := icmp.IPv6PseudoHeader(c.LocalAddr().(*net.IPAddr).IP, dst.IP)
	cm := ipv6.ControlMessage{
		TrafficClass: iana.DiffServAF11 | iana.CongestionExperienced,
		Src:          net.IPv6loopback,
	}
	cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagLoopback)
	if ifi != nil {
		cm.IfIndex = ifi.Index
	}

	var f ipv6.ICMPFilter
	f.SetAll(true)
	f.Accept(ipv6.ICMPTypeEchoReply)
	if err := p.SetICMPFilter(&f); err != nil {
		t.Fatal(err)
	}

	var psh []byte
	for i, toggle := range []bool{true, false, true} {
		if toggle {
			psh = nil
			if err := p.SetChecksum(true, 2); err != nil {
				t.Fatal(err)
			}
		} else {
			psh = pshicmp
			// Some platforms never allow to disable the
			// kernel checksum processing.
			p.SetChecksum(false, -1)
		}
		wb, err := (&icmp.Message{
			Type: ipv6.ICMPTypeEchoRequest, Code: 0,
			Body: &icmp.Echo{
				ID: os.Getpid() & 0xffff, Seq: i + 1,
				Data: []byte("HELLO-R-U-THERE"),
			},
		}).Marshal(psh)
		if err != nil {
			t.Fatal(err)
		}
		if err := p.SetControlMessage(cf, toggle); err != nil {
			if nettest.ProtocolNotSupported(err) {
				t.Skipf("not supported on %q", runtime.GOOS)
			}
			t.Fatal(err)
		}
		cm.HopLimit = i + 1
		if err := p.SetWriteDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, err := p.WriteTo(wb, &cm, dst); err != nil {
			t.Fatal(err)
		} else if n != len(wb) {
			t.Fatalf("got %v; want %v", n, len(wb))
		}
		rb := make([]byte, 128)
		if err := p.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
			t.Fatal(err)
		}
		if n, cm, _, err := p.ReadFrom(rb); err != nil {
			switch runtime.GOOS {
			case "darwin": // older darwin kernels have some limitation on receiving icmp packet through raw socket
				t.Logf("not supported on %q", runtime.GOOS)
				continue
			}
			t.Fatal(err)
		} else {
			t.Logf("rcvd cmsg: %v", cm)
			if m, err := icmp.ParseMessage(iana.ProtocolIPv6ICMP, rb[:n]); err != nil {
				t.Fatal(err)
			} else if m.Type != ipv6.ICMPTypeEchoReply || m.Code != 0 {
				t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv6.ICMPTypeEchoReply, 0)
			}
		}
	}
}
Example #19
0
func TestPacketConnReadWriteMulticastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range packetConnReadWriteMulticastUDPTests {
		c, err := net.ListenPacket("udp4", tt.addr)
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		grp := *tt.grp
		grp.Port = c.LocalAddr().(*net.UDPAddr).Port
		p := ipv4.NewPacketConn(c)
		defer p.Close()
		if tt.src == nil {
			if err := p.JoinGroup(ifi, &grp); err != nil {
				t.Fatal(err)
			}
			defer p.LeaveGroup(ifi, &grp)
		} else {
			if err := p.JoinSourceSpecificGroup(ifi, &grp, tt.src); err != nil {
				switch runtime.GOOS {
				case "freebsd", "linux":
				default: // platforms that don't support IGMPv2/3 fail here
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			defer p.LeaveSourceSpecificGroup(ifi, &grp, tt.src)
		}
		if err := p.SetMulticastInterface(ifi); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastInterface(); err != nil {
			t.Fatal(err)
		}
		if err := p.SetMulticastLoopback(true); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastLoopback(); err != nil {
			t.Fatal(err)
		}
		cf := ipv4.FlagTTL | ipv4.FlagDst | ipv4.FlagInterface
		wb := []byte("HELLO-R-U-THERE")

		for i, toggle := range []bool{true, false, true} {
			if err := p.SetControlMessage(cf, toggle); err != nil {
				if nettest.ProtocolNotSupported(err) {
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			if err := p.SetDeadline(time.Now().Add(200 * time.Millisecond)); err != nil {
				t.Fatal(err)
			}
			p.SetMulticastTTL(i + 1)
			if n, err := p.WriteTo(wb, nil, &grp); err != nil {
				t.Fatal(err)
			} else if n != len(wb) {
				t.Fatalf("got %v; want %v", n, len(wb))
			}
			rb := make([]byte, 128)
			if n, _, _, err := p.ReadFrom(rb); err != nil {
				t.Fatal(err)
			} else if !bytes.Equal(rb[:n], wb) {
				t.Fatalf("got %v; want %v", rb[:n], wb)
			}
		}
	}
}
Example #20
0
func TestRawConnReadWriteMulticastICMP(t *testing.T) {
	if testing.Short() {
		t.Skip("to avoid external network")
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range rawConnReadWriteMulticastICMPTests {
		c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		r, err := ipv4.NewRawConn(c)
		if err != nil {
			t.Fatal(err)
		}
		defer r.Close()
		if tt.src == nil {
			if err := r.JoinGroup(ifi, tt.grp); err != nil {
				t.Fatal(err)
			}
			defer r.LeaveGroup(ifi, tt.grp)
		} else {
			if err := r.JoinSourceSpecificGroup(ifi, tt.grp, tt.src); err != nil {
				switch runtime.GOOS {
				case "freebsd", "linux":
				default: // platforms that don't support IGMPv2/3 fail here
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			defer r.LeaveSourceSpecificGroup(ifi, tt.grp, tt.src)
		}
		if err := r.SetMulticastInterface(ifi); err != nil {
			t.Fatal(err)
		}
		if _, err := r.MulticastInterface(); err != nil {
			t.Fatal(err)
		}
		if err := r.SetMulticastLoopback(true); err != nil {
			t.Fatal(err)
		}
		if _, err := r.MulticastLoopback(); err != nil {
			t.Fatal(err)
		}
		cf := ipv4.FlagTTL | ipv4.FlagDst | ipv4.FlagInterface

		for i, toggle := range []bool{true, false, true} {
			wb, err := (&icmp.Message{
				Type: ipv4.ICMPTypeEcho, Code: 0,
				Body: &icmp.Echo{
					ID: os.Getpid() & 0xffff, Seq: i + 1,
					Data: []byte("HELLO-R-U-THERE"),
				},
			}).Marshal(nil)
			if err != nil {
				t.Fatal(err)
			}
			wh := &ipv4.Header{
				Version:  ipv4.Version,
				Len:      ipv4.HeaderLen,
				TOS:      i + 1,
				TotalLen: ipv4.HeaderLen + len(wb),
				Protocol: 1,
				Dst:      tt.grp.IP,
			}
			if err := r.SetControlMessage(cf, toggle); err != nil {
				if nettest.ProtocolNotSupported(err) {
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			if err := r.SetDeadline(time.Now().Add(200 * time.Millisecond)); err != nil {
				t.Fatal(err)
			}
			r.SetMulticastTTL(i + 1)
			if err := r.WriteTo(wh, wb, nil); err != nil {
				t.Fatal(err)
			}
			rb := make([]byte, ipv4.HeaderLen+128)
			if rh, b, _, err := r.ReadFrom(rb); err != nil {
				t.Fatal(err)
			} else {
				m, err := icmp.ParseMessage(iana.ProtocolICMP, b)
				if err != nil {
					t.Fatal(err)
				}
				switch {
				case (rh.Dst.IsLoopback() || rh.Dst.IsLinkLocalUnicast() || rh.Dst.IsGlobalUnicast()) && m.Type == ipv4.ICMPTypeEchoReply && m.Code == 0: // net.inet.icmp.bmcastecho=1
				case rh.Dst.IsMulticast() && m.Type == ipv4.ICMPTypeEcho && m.Code == 0: // net.inet.icmp.bmcastecho=0
				default:
					t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv4.ICMPTypeEchoReply, 0)
				}
			}
		}
	}
}
Example #21
0
func TestPacketConnReadWriteMulticastICMP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "solaris", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range packetConnReadWriteMulticastICMPTests {
		c, err := net.ListenPacket("ip4:icmp", "0.0.0.0")
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		p := ipv4.NewPacketConn(c)
		defer p.Close()
		if tt.src == nil {
			if err := p.JoinGroup(ifi, tt.grp); err != nil {
				t.Fatal(err)
			}
			defer p.LeaveGroup(ifi, tt.grp)
		} else {
			if err := p.JoinSourceSpecificGroup(ifi, tt.grp, tt.src); err != nil {
				switch runtime.GOOS {
				case "freebsd", "linux":
				default: // platforms that don't support IGMPv2/3 fail here
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			defer p.LeaveSourceSpecificGroup(ifi, tt.grp, tt.src)
		}
		if err := p.SetMulticastInterface(ifi); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastInterface(); err != nil {
			t.Fatal(err)
		}
		if err := p.SetMulticastLoopback(true); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastLoopback(); err != nil {
			t.Fatal(err)
		}
		cf := ipv4.FlagDst | ipv4.FlagInterface
		if runtime.GOOS != "solaris" {
			// Solaris never allows to modify ICMP properties.
			cf |= ipv4.FlagTTL
		}

		for i, toggle := range []bool{true, false, true} {
			wb, err := (&icmp.Message{
				Type: ipv4.ICMPTypeEcho, Code: 0,
				Body: &icmp.Echo{
					ID: os.Getpid() & 0xffff, Seq: i + 1,
					Data: []byte("HELLO-R-U-THERE"),
				},
			}).Marshal(nil)
			if err != nil {
				t.Fatal(err)
			}
			if err := p.SetControlMessage(cf, toggle); err != nil {
				if nettest.ProtocolNotSupported(err) {
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			if err := p.SetDeadline(time.Now().Add(200 * time.Millisecond)); err != nil {
				t.Fatal(err)
			}
			p.SetMulticastTTL(i + 1)
			if n, err := p.WriteTo(wb, nil, tt.grp); err != nil {
				t.Fatal(err)
			} else if n != len(wb) {
				t.Fatalf("got %v; want %v", n, len(wb))
			}
			rb := make([]byte, 128)
			if n, _, _, err := p.ReadFrom(rb); err != nil {
				t.Fatal(err)
			} else {
				m, err := icmp.ParseMessage(iana.ProtocolICMP, rb[:n])
				if err != nil {
					t.Fatal(err)
				}
				switch {
				case m.Type == ipv4.ICMPTypeEchoReply && m.Code == 0: // net.inet.icmp.bmcastecho=1
				case m.Type == ipv4.ICMPTypeEcho && m.Code == 0: // net.inet.icmp.bmcastecho=0
				default:
					t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv4.ICMPTypeEchoReply, 0)
				}
			}
		}
	}
}
Example #22
0
func TestPacketConnConcurrentReadWriteUnicastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}

	c, err := net.ListenPacket("udp4", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer c.Close()
	p := ipv4.NewPacketConn(c)
	defer p.Close()

	dst, err := net.ResolveUDPAddr("udp4", c.LocalAddr().String())
	if err != nil {
		t.Fatal(err)
	}

	ifi := nettest.RoutedInterface("ip4", net.FlagUp|net.FlagLoopback)
	cf := ipv4.FlagTTL | ipv4.FlagSrc | ipv4.FlagDst | ipv4.FlagInterface
	wb := []byte("HELLO-R-U-THERE")

	if err := p.SetControlMessage(cf, true); err != nil { // probe before test
		if nettest.ProtocolNotSupported(err) {
			t.Skipf("not supported on %s", runtime.GOOS)
		}
		t.Fatal(err)
	}

	var wg sync.WaitGroup
	reader := func() {
		defer wg.Done()
		rb := make([]byte, 128)
		if n, cm, _, err := p.ReadFrom(rb); err != nil {
			t.Error(err)
			return
		} else if !bytes.Equal(rb[:n], wb) {
			t.Errorf("got %v; want %v", rb[:n], wb)
			return
		} else {
			s := cm.String()
			if strings.Contains(s, ",") {
				t.Errorf("should be space-separated values: %s", s)
			}
		}
	}
	writer := func(toggle bool) {
		defer wg.Done()
		cm := ipv4.ControlMessage{
			Src: net.IPv4(127, 0, 0, 1),
		}
		if ifi != nil {
			cm.IfIndex = ifi.Index
		}
		if err := p.SetControlMessage(cf, toggle); err != nil {
			t.Error(err)
			return
		}
		if n, err := p.WriteTo(wb, &cm, dst); err != nil {
			t.Error(err)
			return
		} else if n != len(wb) {
			t.Errorf("short write: %v", n)
			return
		}
	}

	const N = 10
	wg.Add(N)
	for i := 0; i < N; i++ {
		go reader()
	}
	wg.Add(2 * N)
	for i := 0; i < 2*N; i++ {
		go writer(i%2 != 0)
	}
	wg.Add(N)
	for i := 0; i < N; i++ {
		go reader()
	}
	wg.Wait()
}
Example #23
0
func TestPacketConnReadWriteMulticastICMP(t *testing.T) {
	switch runtime.GOOS {
	case "freebsd": // due to a bug on loopback marking
		// See http://www.freebsd.org/cgi/query-pr.cgi?pr=180065.
		t.Skipf("not supported on %s", runtime.GOOS)
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}
	if m, ok := nettest.SupportsRawIPSocket(); !ok {
		t.Skip(m)
	}
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range packetConnReadWriteMulticastICMPTests {
		c, err := net.ListenPacket("ip6:ipv6-icmp", "::")
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		pshicmp := icmp.IPv6PseudoHeader(c.LocalAddr().(*net.IPAddr).IP, tt.grp.IP)
		p := ipv6.NewPacketConn(c)
		defer p.Close()
		if tt.src == nil {
			if err := p.JoinGroup(ifi, tt.grp); err != nil {
				t.Fatal(err)
			}
			defer p.LeaveGroup(ifi, tt.grp)
		} else {
			if err := p.JoinSourceSpecificGroup(ifi, tt.grp, tt.src); err != nil {
				switch runtime.GOOS {
				case "freebsd", "linux":
				default: // platforms that don't support MLDv2 fail here
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			defer p.LeaveSourceSpecificGroup(ifi, tt.grp, tt.src)
		}
		if err := p.SetMulticastInterface(ifi); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastInterface(); err != nil {
			t.Fatal(err)
		}
		if err := p.SetMulticastLoopback(true); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastLoopback(); err != nil {
			t.Fatal(err)
		}

		cm := ipv6.ControlMessage{
			TrafficClass: iana.DiffServAF11 | iana.CongestionExperienced,
			Src:          net.IPv6loopback,
			IfIndex:      ifi.Index,
		}
		cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU

		var f ipv6.ICMPFilter
		f.SetAll(true)
		f.Accept(ipv6.ICMPTypeEchoReply)
		if err := p.SetICMPFilter(&f); err != nil {
			t.Fatal(err)
		}

		var psh []byte
		for i, toggle := range []bool{true, false, true} {
			if toggle {
				psh = nil
				if err := p.SetChecksum(true, 2); err != nil {
					// Solaris never allows to
					// modify ICMP properties.
					if runtime.GOOS != "solaris" {
						t.Fatal(err)
					}
				}
			} else {
				psh = pshicmp
				// Some platforms never allow to
				// disable the kernel checksum
				// processing.
				p.SetChecksum(false, -1)
			}
			wb, err := (&icmp.Message{
				Type: ipv6.ICMPTypeEchoRequest, Code: 0,
				Body: &icmp.Echo{
					ID: os.Getpid() & 0xffff, Seq: i + 1,
					Data: []byte("HELLO-R-U-THERE"),
				},
			}).Marshal(psh)
			if err != nil {
				t.Fatal(err)
			}
			if err := p.SetControlMessage(cf, toggle); err != nil {
				if nettest.ProtocolNotSupported(err) {
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			if err := p.SetDeadline(time.Now().Add(200 * time.Millisecond)); err != nil {
				t.Fatal(err)
			}
			cm.HopLimit = i + 1
			if n, err := p.WriteTo(wb, &cm, tt.grp); err != nil {
				t.Fatal(err)
			} else if n != len(wb) {
				t.Fatalf("got %v; want %v", n, len(wb))
			}
			rb := make([]byte, 128)
			if n, _, _, err := p.ReadFrom(rb); err != nil {
				switch runtime.GOOS {
				case "darwin": // older darwin kernels have some limitation on receiving icmp packet through raw socket
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			} else {
				if m, err := icmp.ParseMessage(iana.ProtocolIPv6ICMP, rb[:n]); err != nil {
					t.Fatal(err)
				} else if m.Type != ipv6.ICMPTypeEchoReply || m.Code != 0 {
					t.Fatalf("got type=%v, code=%v; want type=%v, code=%v", m.Type, m.Code, ipv6.ICMPTypeEchoReply, 0)
				}
			}
		}
	}
}
Example #24
0
func TestPacketConnReadWriteMulticastUDP(t *testing.T) {
	switch runtime.GOOS {
	case "freebsd": // due to a bug on loopback marking
		// See http://www.freebsd.org/cgi/query-pr.cgi?pr=180065.
		t.Skipf("not supported on %s", runtime.GOOS)
	case "nacl", "plan9", "windows":
		t.Skipf("not supported on %s", runtime.GOOS)
	}
	if !supportsIPv6 {
		t.Skip("ipv6 is not supported")
	}
	ifi := nettest.RoutedInterface("ip6", net.FlagUp|net.FlagMulticast|net.FlagLoopback)
	if ifi == nil {
		t.Skipf("not available on %s", runtime.GOOS)
	}

	for _, tt := range packetConnReadWriteMulticastUDPTests {
		c, err := net.ListenPacket("udp6", tt.addr)
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

		grp := *tt.grp
		grp.Port = c.LocalAddr().(*net.UDPAddr).Port
		p := ipv6.NewPacketConn(c)
		defer p.Close()
		if tt.src == nil {
			if err := p.JoinGroup(ifi, &grp); err != nil {
				t.Fatal(err)
			}
			defer p.LeaveGroup(ifi, &grp)
		} else {
			if err := p.JoinSourceSpecificGroup(ifi, &grp, tt.src); err != nil {
				switch runtime.GOOS {
				case "freebsd", "linux":
				default: // platforms that don't support MLDv2 fail here
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			defer p.LeaveSourceSpecificGroup(ifi, &grp, tt.src)
		}
		if err := p.SetMulticastInterface(ifi); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastInterface(); err != nil {
			t.Fatal(err)
		}
		if err := p.SetMulticastLoopback(true); err != nil {
			t.Fatal(err)
		}
		if _, err := p.MulticastLoopback(); err != nil {
			t.Fatal(err)
		}

		cm := ipv6.ControlMessage{
			TrafficClass: iana.DiffServAF11 | iana.CongestionExperienced,
			Src:          net.IPv6loopback,
			IfIndex:      ifi.Index,
		}
		cf := ipv6.FlagTrafficClass | ipv6.FlagHopLimit | ipv6.FlagSrc | ipv6.FlagDst | ipv6.FlagInterface | ipv6.FlagPathMTU
		wb := []byte("HELLO-R-U-THERE")

		for i, toggle := range []bool{true, false, true} {
			if err := p.SetControlMessage(cf, toggle); err != nil {
				if nettest.ProtocolNotSupported(err) {
					t.Logf("not supported on %s", runtime.GOOS)
					continue
				}
				t.Fatal(err)
			}
			if err := p.SetDeadline(time.Now().Add(200 * time.Millisecond)); err != nil {
				t.Fatal(err)
			}
			cm.HopLimit = i + 1
			if n, err := p.WriteTo(wb, &cm, &grp); err != nil {
				t.Fatal(err)
			} else if n != len(wb) {
				t.Fatal(err)
			}
			rb := make([]byte, 128)
			if n, _, _, err := p.ReadFrom(rb); err != nil {
				t.Fatal(err)
			} else if !bytes.Equal(rb[:n], wb) {
				t.Fatalf("got %v; want %v", rb[:n], wb)
			}
		}
	}
}