diff options
Diffstat (limited to 'pkg/tcpip/stack/nic.go')
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 127 |
1 files changed, 73 insertions, 54 deletions
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 0707c3ce2..c813b0da5 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -16,7 +16,6 @@ package stack import ( "fmt" - "math/rand" "reflect" "sync/atomic" @@ -25,6 +24,21 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/header" ) +type neighborTable interface { + neighbors() ([]NeighborEntry, tcpip.Error) + addStaticEntry(tcpip.Address, tcpip.LinkAddress) + get(addr tcpip.Address, linkRes LinkAddressResolver, localAddr tcpip.Address, onResolve func(LinkResolutionResult)) (tcpip.LinkAddress, <-chan struct{}, tcpip.Error) + remove(tcpip.Address) tcpip.Error + removeAll() tcpip.Error + + handleProbe(tcpip.Address, tcpip.LinkAddress, LinkAddressResolver) + handleConfirmation(tcpip.Address, tcpip.LinkAddress, ReachabilityConfirmationFlags) + handleUpperLevelConfirmation(tcpip.Address) + + nudConfig() (NUDConfigurations, tcpip.Error) + setNUDConfig(NUDConfigurations) tcpip.Error +} + var _ NetworkInterface = (*NIC)(nil) // NIC represents a "network interface card" to which the networking stack is @@ -38,7 +52,6 @@ type NIC struct { context NICContext stats NICStats - neigh *neighborCache // The network endpoints themselves may be modified by calling the interface's // methods, but the map reference and entries must be constant. @@ -54,7 +67,7 @@ type NIC struct { // complete. linkResQueue packetsPendingLinkResolution - linkAddrCache *linkAddrCache + neighborTable neighborTable mu struct { sync.RWMutex @@ -143,26 +156,20 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver), } nic.linkResQueue.init(nic) - nic.linkAddrCache = newLinkAddrCache(nic, ageLimit, resolutionTimeout, resolutionAttempts) nic.mu.packetEPs = make(map[tcpip.NetworkProtocolNumber]*packetEndpointList) - // Check for Neighbor Unreachability Detection support. - var nud NUDHandler - if ep.Capabilities()&CapabilityResolutionRequired != 0 && stack.useNeighborCache { - rng := rand.New(rand.NewSource(stack.clock.NowNanoseconds())) - nic.neigh = &neighborCache{ - nic: nic, - state: NewNUDState(stack.nudConfigs, rng), - cache: make(map[tcpip.Address]*neighborEntry, neighborCacheSize), - } + resolutionRequired := ep.Capabilities()&CapabilityResolutionRequired != 0 - // An interface value that holds a nil pointer but non-nil type is not the - // same as the nil interface. Because of this, nud must only be assignd if - // nic.neigh is non-nil since a nil reference to a neighborCache is not - // valid. - // - // See https://golang.org/doc/faq#nil_error for more information. - nud = nic.neigh + if resolutionRequired { + if stack.useNeighborCache { + nic.neighborTable = &neighborCache{ + nic: nic, + state: NewNUDState(stack.nudConfigs, stack.randomGenerator), + cache: make(map[tcpip.Address]*neighborEntry, neighborCacheSize), + } + } else { + nic.neighborTable = newLinkAddrCache(nic, ageLimit, resolutionTimeout, resolutionAttempts) + } } // Register supported packet and network endpoint protocols. @@ -173,11 +180,13 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC netNum := netProto.Number() nic.mu.packetEPs[netNum] = new(packetEndpointList) - netEP := netProto.NewEndpoint(nic, nic.linkAddrCache, nud, nic) + netEP := netProto.NewEndpoint(nic, nic) nic.networkEndpoints[netNum] = netEP - if r, ok := netEP.(LinkAddressResolver); ok { - nic.linkAddrResolvers[r.LinkAddressProtocol()] = r + if resolutionRequired { + if r, ok := netEP.(LinkAddressResolver); ok { + nic.linkAddrResolvers[r.LinkAddressProtocol()] = r + } } } @@ -596,8 +605,8 @@ func (n *NIC) removeAddress(addr tcpip.Address) tcpip.Error { } func (n *NIC) confirmReachable(addr tcpip.Address) { - if n := n.neigh; n != nil { - n.handleUpperLevelConfirmation(addr) + if n.neighborTable != nil { + n.neighborTable.handleUpperLevelConfirmation(addr) } } @@ -617,49 +626,44 @@ func (n *NIC) getLinkAddress(addr, localAddr tcpip.Address, protocol tcpip.Netwo } func (n *NIC) getNeighborLinkAddress(addr, localAddr tcpip.Address, linkRes LinkAddressResolver, onResolve func(LinkResolutionResult)) (tcpip.LinkAddress, <-chan struct{}, tcpip.Error) { - if n.neigh != nil { - entry, ch, err := n.neigh.entry(addr, localAddr, linkRes, onResolve) - return entry.LinkAddr, ch, err + if n.neighborTable != nil { + return n.neighborTable.get(addr, linkRes, localAddr, onResolve) } - return n.linkAddrCache.get(addr, linkRes, localAddr, onResolve) + return "", nil, &tcpip.ErrNotSupported{} } func (n *NIC) neighbors() ([]NeighborEntry, tcpip.Error) { - if n.neigh == nil { - return nil, &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + return n.neighborTable.neighbors() } - return n.neigh.entries(), nil + return nil, &tcpip.ErrNotSupported{} } func (n *NIC) addStaticNeighbor(addr tcpip.Address, linkAddress tcpip.LinkAddress) tcpip.Error { - if n.neigh == nil { - return &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + n.neighborTable.addStaticEntry(addr, linkAddress) + return nil } - n.neigh.addStaticEntry(addr, linkAddress) - return nil + return &tcpip.ErrNotSupported{} } func (n *NIC) removeNeighbor(addr tcpip.Address) tcpip.Error { - if n.neigh == nil { - return &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + return n.neighborTable.remove(addr) } - if !n.neigh.removeEntry(addr) { - return &tcpip.ErrBadAddress{} - } - return nil + return &tcpip.ErrNotSupported{} } func (n *NIC) clearNeighbors() tcpip.Error { - if n.neigh == nil { - return &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + return n.neighborTable.removeAll() } - n.neigh.clear() - return nil + return &tcpip.ErrNotSupported{} } // joinGroup adds a new endpoint for the given multicast address, if none @@ -944,10 +948,11 @@ func (n *NIC) Name() string { // nudConfigs gets the NUD configurations for n. func (n *NIC) nudConfigs() (NUDConfigurations, tcpip.Error) { - if n.neigh == nil { - return NUDConfigurations{}, &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + return n.neighborTable.nudConfig() } - return n.neigh.config(), nil + + return NUDConfigurations{}, &tcpip.ErrNotSupported{} } // setNUDConfigs sets the NUD configurations for n. @@ -955,12 +960,12 @@ func (n *NIC) nudConfigs() (NUDConfigurations, tcpip.Error) { // Note, if c contains invalid NUD configuration values, it will be fixed to // use default values for the erroneous values. func (n *NIC) setNUDConfigs(c NUDConfigurations) tcpip.Error { - if n.neigh == nil { - return &tcpip.ErrNotSupported{} + if n.neighborTable != nil { + c.resetInvalidFields() + return n.neighborTable.setNUDConfig(c) } - c.resetInvalidFields() - n.neigh.setConfig(c) - return nil + + return &tcpip.ErrNotSupported{} } func (n *NIC) registerPacketEndpoint(netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) tcpip.Error { @@ -996,3 +1001,17 @@ func (n *NIC) isValidForOutgoing(ep AssignableAddressEndpoint) bool { n.mu.RUnlock() return n.Enabled() && ep.IsAssigned(spoofing) } + +// HandleNeighborProbe implements NetworkInterface. +func (n *NIC) HandleNeighborProbe(addr tcpip.Address, linkAddr tcpip.LinkAddress, linkRes LinkAddressResolver) { + if n.neighborTable != nil { + n.neighborTable.handleProbe(addr, linkAddr, linkRes) + } +} + +// HandleNeighborConfirmation implements NetworkInterface. +func (n *NIC) HandleNeighborConfirmation(addr tcpip.Address, linkAddr tcpip.LinkAddress, flags ReachabilityConfirmationFlags) { + if n.neighborTable != nil { + n.neighborTable.handleConfirmation(addr, linkAddr, flags) + } +} |