diff options
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 25 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 5 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack_test.go | 56 |
3 files changed, 68 insertions, 18 deletions
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index b2be18e47..862954ab2 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -44,8 +44,7 @@ type NIC struct { linkEP LinkEndpoint context NICContext - stats NICStats - attach sync.Once + stats NICStats mu struct { sync.RWMutex @@ -141,6 +140,8 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC nic.mu.packetEPs[netProto.Number()] = []PacketEndpoint{} } + nic.linkEP.Attach(nic) + return nic } @@ -200,14 +201,16 @@ func (n *NIC) disable() *tcpip.Error { } } - // TODO(b/147015577): Should n detach from its LinkEndpoint? - n.mu.enabled = false return nil } -// enable enables n. enable will attach the nic to its LinkEndpoint and -// join the IPv6 All-Nodes Multicast address (ff02::1). +// enable enables n. +// +// If the stack has IPv6 enabled, enable will join the IPv6 All-Nodes Multicast +// address (ff02::1), start DAD for permanent addresses, and start soliciting +// routers if the stack is not operating as a router. If the stack is also +// configured to auto-generate a link-local address, one will be generated. func (n *NIC) enable() *tcpip.Error { n.mu.RLock() enabled := n.mu.enabled @@ -225,8 +228,6 @@ func (n *NIC) enable() *tcpip.Error { n.mu.enabled = true - n.attachLinkEndpoint() - // Create an endpoint to receive broadcast packets on this interface. if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { if _, err := n.addAddressLocked(ipv4BroadcastAddr, NeverPrimaryEndpoint, permanent, static, false /* deprecated */); err != nil { @@ -321,14 +322,6 @@ func (n *NIC) becomeIPv6Host() { n.mu.ndp.startSolicitingRouters() } -// attachLinkEndpoint attaches the NIC to the endpoint, which will enable it -// to start delivering packets. -func (n *NIC) attachLinkEndpoint() { - n.attach.Do(func() { - n.linkEP.Attach(n) - }) -} - // setPromiscuousMode enables or disables promiscuous mode. func (n *NIC) setPromiscuousMode(enable bool) { n.mu.Lock() diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index fabc976a7..f0ed76fbe 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -881,6 +881,8 @@ type NICOptions struct { // CreateNICWithOptions creates a NIC with the provided id, LinkEndpoint, and // NICOptions. See the documentation on type NICOptions for details on how // NICs can be configured. +// +// LinkEndpoint.Attach will be called to bind ep with a NetworkDispatcher. func (s *Stack) CreateNICWithOptions(id tcpip.NICID, ep LinkEndpoint, opts NICOptions) *tcpip.Error { s.mu.Lock() defer s.mu.Unlock() @@ -900,7 +902,6 @@ func (s *Stack) CreateNICWithOptions(id tcpip.NICID, ep LinkEndpoint, opts NICOp } n := newNIC(s, id, opts.Name, ep, opts.Context) - s.nics[id] = n if !opts.Disabled { return n.enable() @@ -910,7 +911,7 @@ func (s *Stack) CreateNICWithOptions(id tcpip.NICID, ep LinkEndpoint, opts NICOp } // CreateNIC creates a NIC with the provided id and LinkEndpoint and calls -// `LinkEndpoint.Attach` to start delivering packets to it. +// LinkEndpoint.Attach to bind ep with a NetworkDispatcher. func (s *Stack) CreateNIC(id tcpip.NICID, ep LinkEndpoint) *tcpip.Error { return s.CreateNICWithOptions(id, ep, NICOptions{}) } diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index eb6f7d1fc..18016e7db 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -239,6 +239,23 @@ func fakeNetFactory() stack.NetworkProtocol { return &fakeNetworkProtocol{} } +// linkEPWithMockedAttach is a stack.LinkEndpoint that tests can use to verify +// that LinkEndpoint.Attach was called. +type linkEPWithMockedAttach struct { + stack.LinkEndpoint + attached bool +} + +// Attach implements stack.LinkEndpoint.Attach. +func (l *linkEPWithMockedAttach) Attach(d stack.NetworkDispatcher) { + l.LinkEndpoint.Attach(d) + l.attached = true +} + +func (l *linkEPWithMockedAttach) isAttached() bool { + return l.attached +} + func TestNetworkReceive(t *testing.T) { // Create a stack with the fake network protocol, one nic, and two // addresses attached to it: 1 & 2. @@ -510,6 +527,45 @@ func testNoRoute(t *testing.T, s *stack.Stack, nic tcpip.NICID, srcAddr, dstAddr } } +// TestAttachToLinkEndpointImmediately tests that a LinkEndpoint is attached to +// a NetworkDispatcher when the NIC is created. +func TestAttachToLinkEndpointImmediately(t *testing.T) { + const nicID = 1 + + tests := []struct { + name string + nicOpts stack.NICOptions + }{ + { + name: "Create enabled NIC", + nicOpts: stack.NICOptions{Disabled: false}, + }, + { + name: "Create disabled NIC", + nicOpts: stack.NICOptions{Disabled: true}, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + + e := linkEPWithMockedAttach{ + LinkEndpoint: loopback.New(), + } + + if err := s.CreateNICWithOptions(nicID, &e, test.nicOpts); err != nil { + t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, test.nicOpts, err) + } + if !e.isAttached() { + t.Fatalf("link endpoint not attached to a network disatcher") + } + }) + } +} + func TestDisableUnknownNIC(t *testing.T) { s := stack.New(stack.Options{ NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, |