diff options
Diffstat (limited to 'pkg/tcpip/stack/nic.go')
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 125 |
1 files changed, 78 insertions, 47 deletions
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 6cf54cc89..8828cc5fe 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -32,10 +32,11 @@ var _ NetworkInterface = (*NIC)(nil) // NIC represents a "network interface card" to which the networking stack is // attached. type NIC struct { + LinkEndpoint + stack *Stack id tcpip.NICID name string - linkEP LinkEndpoint context NICContext stats NICStats @@ -91,10 +92,11 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC // of IPv6 is supported on this endpoint's LinkEndpoint. nic := &NIC{ + LinkEndpoint: ep, + stack: stack, id: id, name: name, - linkEP: ep, context: ctx, stats: makeNICStats(), networkEndpoints: make(map[tcpip.NetworkProtocolNumber]NetworkEndpoint), @@ -130,7 +132,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC nic.networkEndpoints[netNum] = netProto.NewEndpoint(nic, stack, nud, nic) } - nic.linkEP.Attach(nic) + nic.LinkEndpoint.Attach(nic) return nic } @@ -220,7 +222,7 @@ func (n *NIC) remove() *tcpip.Error { } // Detach from link endpoint, so no packet comes in. - n.linkEP.Attach(nil) + n.LinkEndpoint.Attach(nil) return nil } @@ -240,7 +242,64 @@ func (n *NIC) isPromiscuousMode() bool { // IsLoopback implements NetworkInterface. func (n *NIC) IsLoopback() bool { - return n.linkEP.Capabilities()&CapabilityLoopback != 0 + return n.LinkEndpoint.Capabilities()&CapabilityLoopback != 0 +} + +// WritePacket implements NetworkLinkEndpoint. +func (n *NIC) WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error { + // As per relevant RFCs, we should queue packets while we wait for link + // resolution to complete. + // + // RFC 1122 section 2.3.2.2 (for IPv4): + // The link layer SHOULD save (rather than discard) at least + // one (the latest) packet of each set of packets destined to + // the same unresolved IP address, and transmit the saved + // packet when the address has been resolved. + // + // RFC 4861 section 5.2 (for IPv6): + // Once the IP address of the next-hop node is known, the sender + // examines the Neighbor Cache for link-layer information about that + // neighbor. If no entry exists, the sender creates one, sets its state + // to INCOMPLETE, initiates Address Resolution, and then queues the data + // packet pending completion of address resolution. + if ch, err := r.Resolve(nil); err != nil { + if err == tcpip.ErrWouldBlock { + r := r.Clone() + n.stack.linkResQueue.enqueue(ch, &r, protocol, pkt) + return nil + } + return err + } + + return n.writePacket(r, gso, protocol, pkt) +} + +func (n *NIC) writePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) *tcpip.Error { + // WritePacket takes ownership of pkt, calculate numBytes first. + numBytes := pkt.Size() + + if err := n.LinkEndpoint.WritePacket(r, gso, protocol, pkt); err != nil { + return err + } + + n.stats.Tx.Packets.Increment() + n.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) + return nil +} + +// WritePackets implements NetworkLinkEndpoint. +func (n *NIC) WritePackets(r *Route, gso *GSO, pkts PacketBufferList, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) { + // TODO(gvisor.dev/issue/4458): Queue packets whie link address resolution + // is being peformed like WritePacket. + writtenPackets, err := n.LinkEndpoint.WritePackets(r, gso, pkts, protocol) + n.stats.Tx.Packets.IncrementBy(uint64(writtenPackets)) + writtenBytes := 0 + for i, pb := 0, pkts.Front(); i < writtenPackets && pb != nil; i, pb = i+1, pb.Next() { + writtenBytes += pb.Size() + } + + n.stats.Tx.Bytes.IncrementBy(uint64(writtenBytes)) + return writtenPackets, err } // setSpoofing enables or disables address spoofing. @@ -525,7 +584,7 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp // If no local link layer address is provided, assume it was sent // directly to this NIC. if local == "" { - local = n.linkEP.LinkAddress() + local = n.LinkEndpoint.LinkAddress() } // Are any packet type sockets listening for this network protocol? @@ -605,7 +664,7 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp n := r.nic if addressEndpoint := n.getAddressOrCreateTempInner(protocol, dst, false, NeverPrimaryEndpoint); addressEndpoint != nil { if n.isValidForOutgoing(addressEndpoint) { - r.LocalLinkAddress = n.linkEP.LinkAddress() + r.LocalLinkAddress = n.LinkEndpoint.LinkAddress() r.RemoteLinkAddress = remote r.RemoteAddress = src // TODO(b/123449044): Update the source NIC as well. @@ -620,21 +679,21 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp // n doesn't have a destination endpoint. // Send the packet out of n. - // TODO(b/128629022): move this logic to route.WritePacket. // TODO(gvisor.dev/issue/1085): According to the RFC, we must decrease the TTL field for ipv4/ipv6. - if ch, err := r.Resolve(nil); err != nil { - if err == tcpip.ErrWouldBlock { - n.stack.forwarder.enqueue(ch, n, &r, protocol, pkt) - // forwarder will release route. - return - } + + // pkt may have set its header and may not have enough headroom for + // link-layer header for the other link to prepend. Here we create a new + // packet to forward. + fwdPkt := NewPacketBuffer(PacketBufferOptions{ + ReserveHeaderBytes: int(n.LinkEndpoint.MaxHeaderLength()), + Data: buffer.NewVectorisedView(pkt.Size(), pkt.Views()), + }) + + // TODO(b/143425874) Decrease the TTL field in forwarded packets. + if err := n.WritePacket(&r, nil, protocol, fwdPkt); err != nil { n.stack.stats.IP.InvalidDestinationAddressesReceived.Increment() - r.Release() - return } - // The link-address resolution finished immediately. - n.forwardPacket(&r, protocol, pkt) r.Release() return } @@ -658,34 +717,11 @@ func (n *NIC) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tc p.PktType = tcpip.PacketOutgoing // Add the link layer header as outgoing packets are intercepted // before the link layer header is created. - n.linkEP.AddHeader(local, remote, protocol, p) + n.LinkEndpoint.AddHeader(local, remote, protocol, p) ep.HandlePacket(n.id, local, protocol, p) } } -func (n *NIC) forwardPacket(r *Route, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) { - // TODO(b/143425874) Decrease the TTL field in forwarded packets. - - // pkt may have set its header and may not have enough headroom for link-layer - // header for the other link to prepend. Here we create a new packet to - // forward. - fwdPkt := NewPacketBuffer(PacketBufferOptions{ - ReserveHeaderBytes: int(n.linkEP.MaxHeaderLength()), - Data: buffer.NewVectorisedView(pkt.Size(), pkt.Views()), - }) - - // WritePacket takes ownership of fwdPkt, calculate numBytes first. - numBytes := fwdPkt.Size() - - if err := n.linkEP.WritePacket(r, nil /* gso */, protocol, fwdPkt); err != nil { - r.Stats().IP.OutgoingPacketErrors.Increment() - return - } - - n.stats.Tx.Packets.Increment() - n.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) -} - // DeliverTransportPacket delivers the packets to the appropriate transport // protocol endpoint. func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt *PacketBuffer) TransportPacketDisposition { @@ -796,11 +832,6 @@ func (n *NIC) Name() string { return n.name } -// LinkEndpoint implements NetworkInterface. -func (n *NIC) LinkEndpoint() LinkEndpoint { - return n.linkEP -} - // nudConfigs gets the NUD configurations for n. func (n *NIC) nudConfigs() (NUDConfigurations, *tcpip.Error) { if n.neigh == nil { |