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-rw-r--r--pkg/tcpip/stack/forwarder_test.go635
1 files changed, 635 insertions, 0 deletions
diff --git a/pkg/tcpip/stack/forwarder_test.go b/pkg/tcpip/stack/forwarder_test.go
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index 000000000..321b7524d
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+++ b/pkg/tcpip/stack/forwarder_test.go
@@ -0,0 +1,635 @@
+// Copyright 2020 The gVisor 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 stack
+
+import (
+ "encoding/binary"
+ "math"
+ "testing"
+ "time"
+
+ "gvisor.dev/gvisor/pkg/tcpip"
+ "gvisor.dev/gvisor/pkg/tcpip/buffer"
+)
+
+const (
+ fwdTestNetNumber tcpip.NetworkProtocolNumber = math.MaxUint32
+ fwdTestNetHeaderLen = 12
+ fwdTestNetDefaultPrefixLen = 8
+
+ // fwdTestNetDefaultMTU is the MTU, in bytes, used throughout the tests,
+ // except where another value is explicitly used. It is chosen to match
+ // the MTU of loopback interfaces on linux systems.
+ fwdTestNetDefaultMTU = 65536
+)
+
+// fwdTestNetworkEndpoint is a network-layer protocol endpoint.
+// Headers of this protocol are fwdTestNetHeaderLen bytes, but we currently only
+// use the first three: destination address, source address, and transport
+// protocol. They're all one byte fields to simplify parsing.
+type fwdTestNetworkEndpoint struct {
+ nicID tcpip.NICID
+ id NetworkEndpointID
+ prefixLen int
+ proto *fwdTestNetworkProtocol
+ dispatcher TransportDispatcher
+ ep LinkEndpoint
+}
+
+func (f *fwdTestNetworkEndpoint) MTU() uint32 {
+ return f.ep.MTU() - uint32(f.MaxHeaderLength())
+}
+
+func (f *fwdTestNetworkEndpoint) NICID() tcpip.NICID {
+ return f.nicID
+}
+
+func (f *fwdTestNetworkEndpoint) PrefixLen() int {
+ return f.prefixLen
+}
+
+func (*fwdTestNetworkEndpoint) DefaultTTL() uint8 {
+ return 123
+}
+
+func (f *fwdTestNetworkEndpoint) ID() *NetworkEndpointID {
+ return &f.id
+}
+
+func (f *fwdTestNetworkEndpoint) HandlePacket(r *Route, pkt tcpip.PacketBuffer) {
+ // Consume the network header.
+ b := pkt.Data.First()
+ pkt.Data.TrimFront(fwdTestNetHeaderLen)
+
+ // Dispatch the packet to the transport protocol.
+ f.dispatcher.DeliverTransportPacket(r, tcpip.TransportProtocolNumber(b[2]), pkt)
+}
+
+func (f *fwdTestNetworkEndpoint) MaxHeaderLength() uint16 {
+ return f.ep.MaxHeaderLength() + fwdTestNetHeaderLen
+}
+
+func (f *fwdTestNetworkEndpoint) PseudoHeaderChecksum(protocol tcpip.TransportProtocolNumber, dstAddr tcpip.Address) uint16 {
+ return 0
+}
+
+func (f *fwdTestNetworkEndpoint) Capabilities() LinkEndpointCapabilities {
+ return f.ep.Capabilities()
+}
+
+func (f *fwdTestNetworkEndpoint) WritePacket(r *Route, gso *GSO, params NetworkHeaderParams, pkt tcpip.PacketBuffer) *tcpip.Error {
+ // Add the protocol's header to the packet and send it to the link
+ // endpoint.
+ b := pkt.Header.Prepend(fwdTestNetHeaderLen)
+ b[0] = r.RemoteAddress[0]
+ b[1] = f.id.LocalAddress[0]
+ b[2] = byte(params.Protocol)
+
+ return f.ep.WritePacket(r, gso, fwdTestNetNumber, pkt)
+}
+
+// WritePackets implements LinkEndpoint.WritePackets.
+func (f *fwdTestNetworkEndpoint) WritePackets(r *Route, gso *GSO, pkts []tcpip.PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) {
+ panic("not implemented")
+}
+
+func (*fwdTestNetworkEndpoint) WriteHeaderIncludedPacket(r *Route, pkt tcpip.PacketBuffer) *tcpip.Error {
+ return tcpip.ErrNotSupported
+}
+
+func (*fwdTestNetworkEndpoint) Close() {}
+
+// fwdTestNetworkProtocol is a network-layer protocol that implements Address
+// resolution.
+type fwdTestNetworkProtocol struct {
+ addrCache *linkAddrCache
+ addrResolveDelay time.Duration
+ onLinkAddressResolved func(cache *linkAddrCache, addr tcpip.Address)
+ onResolveStaticAddress func(tcpip.Address) (tcpip.LinkAddress, bool)
+}
+
+func (f *fwdTestNetworkProtocol) Number() tcpip.NetworkProtocolNumber {
+ return fwdTestNetNumber
+}
+
+func (f *fwdTestNetworkProtocol) MinimumPacketSize() int {
+ return fwdTestNetHeaderLen
+}
+
+func (f *fwdTestNetworkProtocol) DefaultPrefixLen() int {
+ return fwdTestNetDefaultPrefixLen
+}
+
+func (*fwdTestNetworkProtocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) {
+ return tcpip.Address(v[1:2]), tcpip.Address(v[0:1])
+}
+
+func (f *fwdTestNetworkProtocol) NewEndpoint(nicID tcpip.NICID, addrWithPrefix tcpip.AddressWithPrefix, linkAddrCache LinkAddressCache, dispatcher TransportDispatcher, ep LinkEndpoint, _ *Stack) (NetworkEndpoint, *tcpip.Error) {
+ return &fwdTestNetworkEndpoint{
+ nicID: nicID,
+ id: NetworkEndpointID{LocalAddress: addrWithPrefix.Address},
+ prefixLen: addrWithPrefix.PrefixLen,
+ proto: f,
+ dispatcher: dispatcher,
+ ep: ep,
+ }, nil
+}
+
+func (f *fwdTestNetworkProtocol) SetOption(option interface{}) *tcpip.Error {
+ return tcpip.ErrUnknownProtocolOption
+}
+
+func (f *fwdTestNetworkProtocol) Option(option interface{}) *tcpip.Error {
+ return tcpip.ErrUnknownProtocolOption
+}
+
+func (f *fwdTestNetworkProtocol) Close() {}
+
+func (f *fwdTestNetworkProtocol) Wait() {}
+
+func (f *fwdTestNetworkProtocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP LinkEndpoint) *tcpip.Error {
+ if f.addrCache != nil && f.onLinkAddressResolved != nil {
+ time.AfterFunc(f.addrResolveDelay, func() {
+ f.onLinkAddressResolved(f.addrCache, addr)
+ })
+ }
+ return nil
+}
+
+func (f *fwdTestNetworkProtocol) ResolveStaticAddress(addr tcpip.Address) (tcpip.LinkAddress, bool) {
+ if f.onResolveStaticAddress != nil {
+ return f.onResolveStaticAddress(addr)
+ }
+ return "", false
+}
+
+func (f *fwdTestNetworkProtocol) LinkAddressProtocol() tcpip.NetworkProtocolNumber {
+ return fwdTestNetNumber
+}
+
+// fwdTestPacketInfo holds all the information about an outbound packet.
+type fwdTestPacketInfo struct {
+ RemoteLinkAddress tcpip.LinkAddress
+ LocalLinkAddress tcpip.LinkAddress
+ Pkt tcpip.PacketBuffer
+}
+
+type fwdTestLinkEndpoint struct {
+ dispatcher NetworkDispatcher
+ mtu uint32
+ linkAddr tcpip.LinkAddress
+
+ // C is where outbound packets are queued.
+ C chan fwdTestPacketInfo
+}
+
+// InjectInbound injects an inbound packet.
+func (e *fwdTestLinkEndpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) {
+ e.InjectLinkAddr(protocol, "", pkt)
+}
+
+// InjectLinkAddr injects an inbound packet with a remote link address.
+func (e *fwdTestLinkEndpoint) InjectLinkAddr(protocol tcpip.NetworkProtocolNumber, remote tcpip.LinkAddress, pkt tcpip.PacketBuffer) {
+ e.dispatcher.DeliverNetworkPacket(e, remote, "" /* local */, protocol, pkt)
+}
+
+// Attach saves the stack network-layer dispatcher for use later when packets
+// are injected.
+func (e *fwdTestLinkEndpoint) Attach(dispatcher NetworkDispatcher) {
+ e.dispatcher = dispatcher
+}
+
+// IsAttached implements stack.LinkEndpoint.IsAttached.
+func (e *fwdTestLinkEndpoint) IsAttached() bool {
+ return e.dispatcher != nil
+}
+
+// MTU implements stack.LinkEndpoint.MTU. It returns the value initialized
+// during construction.
+func (e *fwdTestLinkEndpoint) MTU() uint32 {
+ return e.mtu
+}
+
+// Capabilities implements stack.LinkEndpoint.Capabilities.
+func (e fwdTestLinkEndpoint) Capabilities() LinkEndpointCapabilities {
+ caps := LinkEndpointCapabilities(0)
+ return caps | CapabilityResolutionRequired
+}
+
+// GSOMaxSize returns the maximum GSO packet size.
+func (*fwdTestLinkEndpoint) GSOMaxSize() uint32 {
+ return 1 << 15
+}
+
+// MaxHeaderLength returns the maximum size of the link layer header. Given it
+// doesn't have a header, it just returns 0.
+func (*fwdTestLinkEndpoint) MaxHeaderLength() uint16 {
+ return 0
+}
+
+// LinkAddress returns the link address of this endpoint.
+func (e *fwdTestLinkEndpoint) LinkAddress() tcpip.LinkAddress {
+ return e.linkAddr
+}
+
+func (e fwdTestLinkEndpoint) WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) *tcpip.Error {
+ p := fwdTestPacketInfo{
+ RemoteLinkAddress: r.RemoteLinkAddress,
+ LocalLinkAddress: r.LocalLinkAddress,
+ Pkt: pkt,
+ }
+
+ select {
+ case e.C <- p:
+ default:
+ }
+
+ return nil
+}
+
+// WritePackets stores outbound packets into the channel.
+func (e *fwdTestLinkEndpoint) WritePackets(r *Route, gso *GSO, pkts []tcpip.PacketBuffer, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) {
+ n := 0
+ for _, pkt := range pkts {
+ e.WritePacket(r, gso, protocol, pkt)
+ n++
+ }
+
+ return n, nil
+}
+
+// WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket.
+func (e *fwdTestLinkEndpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error {
+ p := fwdTestPacketInfo{
+ Pkt: tcpip.PacketBuffer{Data: vv},
+ }
+
+ select {
+ case e.C <- p:
+ default:
+ }
+
+ return nil
+}
+
+// Wait implements stack.LinkEndpoint.Wait.
+func (*fwdTestLinkEndpoint) Wait() {}
+
+func fwdTestNetFactory(t *testing.T, proto *fwdTestNetworkProtocol) (ep1, ep2 *fwdTestLinkEndpoint) {
+ // Create a stack with the network protocol and two NICs.
+ s := New(Options{
+ NetworkProtocols: []NetworkProtocol{proto},
+ })
+
+ proto.addrCache = s.linkAddrCache
+
+ // Enable forwarding.
+ s.SetForwarding(true)
+
+ // NIC 1 has the link address "a", and added the network address 1.
+ ep1 = &fwdTestLinkEndpoint{
+ C: make(chan fwdTestPacketInfo, 300),
+ mtu: fwdTestNetDefaultMTU,
+ linkAddr: "a",
+ }
+ if err := s.CreateNIC(1, ep1); err != nil {
+ t.Fatal("CreateNIC #1 failed:", err)
+ }
+ if err := s.AddAddress(1, fwdTestNetNumber, "\x01"); err != nil {
+ t.Fatal("AddAddress #1 failed:", err)
+ }
+
+ // NIC 2 has the link address "b", and added the network address 2.
+ ep2 = &fwdTestLinkEndpoint{
+ C: make(chan fwdTestPacketInfo, 300),
+ mtu: fwdTestNetDefaultMTU,
+ linkAddr: "b",
+ }
+ if err := s.CreateNIC(2, ep2); err != nil {
+ t.Fatal("CreateNIC #2 failed:", err)
+ }
+ if err := s.AddAddress(2, fwdTestNetNumber, "\x02"); err != nil {
+ t.Fatal("AddAddress #2 failed:", err)
+ }
+
+ // Route all packets to NIC 2.
+ {
+ subnet, err := tcpip.NewSubnet("\x00", "\x00")
+ if err != nil {
+ t.Fatal(err)
+ }
+ s.SetRouteTable([]tcpip.Route{{Destination: subnet, NIC: 2}})
+ }
+
+ return ep1, ep2
+}
+
+func TestForwardingWithStaticResolver(t *testing.T) {
+ // Create a network protocol with a static resolver.
+ proto := &fwdTestNetworkProtocol{
+ onResolveStaticAddress:
+ // The network address 3 is resolved to the link address "c".
+ func(addr tcpip.Address) (tcpip.LinkAddress, bool) {
+ if addr == "\x03" {
+ return "c", true
+ }
+ return "", false
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ // Inject an inbound packet to address 3 on NIC 1, and see if it is
+ // forwarded to NIC 2.
+ buf := buffer.NewView(30)
+ buf[0] = 3
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ default:
+ t.Fatal("packet not forwarded")
+ }
+
+ // Test that the static address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+}
+
+func TestForwardingWithFakeResolver(t *testing.T) {
+ // Create a network protocol with a fake resolver.
+ proto := &fwdTestNetworkProtocol{
+ addrResolveDelay: 500 * time.Millisecond,
+ onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) {
+ // Any address will be resolved to the link address "c".
+ cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c")
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ // Inject an inbound packet to address 3 on NIC 1, and see if it is
+ // forwarded to NIC 2.
+ buf := buffer.NewView(30)
+ buf[0] = 3
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ case <-time.After(time.Second):
+ t.Fatal("packet not forwarded")
+ }
+
+ // Test that the address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+}
+
+func TestForwardingWithNoResolver(t *testing.T) {
+ // Create a network protocol without a resolver.
+ proto := &fwdTestNetworkProtocol{}
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ // inject an inbound packet to address 3 on NIC 1, and see if it is
+ // forwarded to NIC 2.
+ buf := buffer.NewView(30)
+ buf[0] = 3
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+
+ select {
+ case <-ep2.C:
+ t.Fatal("Packet should not be forwarded")
+ case <-time.After(time.Second):
+ }
+}
+
+func TestForwardingWithFakeResolverPartialTimeout(t *testing.T) {
+ // Create a network protocol with a fake resolver.
+ proto := &fwdTestNetworkProtocol{
+ addrResolveDelay: 500 * time.Millisecond,
+ onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) {
+ // Only packets to address 3 will be resolved to the
+ // link address "c".
+ if addr == "\x03" {
+ cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c")
+ }
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ // Inject an inbound packet to address 4 on NIC 1. This packet should
+ // not be forwarded.
+ buf := buffer.NewView(30)
+ buf[0] = 4
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+
+ // Inject an inbound packet to address 3 on NIC 1, and see if it is
+ // forwarded to NIC 2.
+ buf = buffer.NewView(30)
+ buf[0] = 3
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ case <-time.After(time.Second):
+ t.Fatal("packet not forwarded")
+ }
+
+ b := p.Pkt.Header.View()
+ if b[0] != 3 {
+ t.Fatalf("got b[0] = %d, want = 3", b[0])
+ }
+
+ // Test that the address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+}
+
+func TestForwardingWithFakeResolverTwoPackets(t *testing.T) {
+ // Create a network protocol with a fake resolver.
+ proto := &fwdTestNetworkProtocol{
+ addrResolveDelay: 500 * time.Millisecond,
+ onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) {
+ // Any packets will be resolved to the link address "c".
+ cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c")
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ // Inject two inbound packets to address 3 on NIC 1.
+ for i := 0; i < 2; i++ {
+ buf := buffer.NewView(30)
+ buf[0] = 3
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+ }
+
+ for i := 0; i < 2; i++ {
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ case <-time.After(time.Second):
+ t.Fatal("packet not forwarded")
+ }
+
+ b := p.Pkt.Header.View()
+ if b[0] != 3 {
+ t.Fatalf("got b[0] = %d, want = 3", b[0])
+ }
+
+ // Test that the address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+ }
+}
+
+func TestForwardingWithFakeResolverManyPackets(t *testing.T) {
+ // Create a network protocol with a fake resolver.
+ proto := &fwdTestNetworkProtocol{
+ addrResolveDelay: 500 * time.Millisecond,
+ onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) {
+ // Any packets will be resolved to the link address "c".
+ cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c")
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ for i := 0; i < maxPendingPacketsPerResolution+5; i++ {
+ // Inject inbound 'maxPendingPacketsPerResolution + 5' packets on NIC 1.
+ buf := buffer.NewView(30)
+ buf[0] = 3
+ // Set the packet sequence number.
+ binary.BigEndian.PutUint16(buf[fwdTestNetHeaderLen:], uint16(i))
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+ }
+
+ for i := 0; i < maxPendingPacketsPerResolution; i++ {
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ case <-time.After(time.Second):
+ t.Fatal("packet not forwarded")
+ }
+
+ b := p.Pkt.Header.View()
+ if b[0] != 3 {
+ t.Fatalf("got b[0] = %d, want = 3", b[0])
+ }
+ // The first 5 packets should not be forwarded so the the
+ // sequemnce number should start with 5.
+ want := uint16(i + 5)
+ if n := binary.BigEndian.Uint16(b[fwdTestNetHeaderLen:]); n != want {
+ t.Fatalf("got the packet #%d, want = #%d", n, want)
+ }
+
+ // Test that the address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+ }
+}
+
+func TestForwardingWithFakeResolverManyResolutions(t *testing.T) {
+ // Create a network protocol with a fake resolver.
+ proto := &fwdTestNetworkProtocol{
+ addrResolveDelay: 500 * time.Millisecond,
+ onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) {
+ // Any packets will be resolved to the link address "c".
+ cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c")
+ },
+ }
+
+ ep1, ep2 := fwdTestNetFactory(t, proto)
+
+ for i := 0; i < maxPendingResolutions+5; i++ {
+ // Inject inbound 'maxPendingResolutions + 5' packets on NIC 1.
+ // Each packet has a different destination address (3 to
+ // maxPendingResolutions + 7).
+ buf := buffer.NewView(30)
+ buf[0] = byte(3 + i)
+ ep1.InjectInbound(fwdTestNetNumber, tcpip.PacketBuffer{
+ Data: buf.ToVectorisedView(),
+ })
+ }
+
+ for i := 0; i < maxPendingResolutions; i++ {
+ var p fwdTestPacketInfo
+
+ select {
+ case p = <-ep2.C:
+ case <-time.After(time.Second):
+ t.Fatal("packet not forwarded")
+ }
+
+ // The first 5 packets (address 3 to 7) should not be forwarded
+ // because their address resolutions are interrupted.
+ b := p.Pkt.Header.View()
+ if b[0] < 8 {
+ t.Fatalf("got b[0] = %d, want b[0] >= 8", b[0])
+ }
+
+ // Test that the address resolution happened correctly.
+ if p.RemoteLinkAddress != "c" {
+ t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress)
+ }
+ if p.LocalLinkAddress != "b" {
+ t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress)
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-27 01:01:44 +0000