diff options
Diffstat (limited to 'pkg')
26 files changed, 350 insertions, 66 deletions
diff --git a/pkg/abi/linux/socket.go b/pkg/abi/linux/socket.go index 4a14ef691..95337c168 100644 --- a/pkg/abi/linux/socket.go +++ b/pkg/abi/linux/socket.go @@ -134,6 +134,15 @@ const ( SHUT_RDWR = 2 ) +// Packet types from <linux/if_packet.h> +const ( + PACKET_HOST = 0 // To us + PACKET_BROADCAST = 1 // To all + PACKET_MULTICAST = 2 // To group + PACKET_OTHERHOST = 3 // To someone else + PACKET_OUTGOING = 4 // Outgoing of any type +) + // Socket options from socket.h. const ( SO_DEBUG = 1 diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go index 49a04e613..964ec8414 100644 --- a/pkg/sentry/socket/netstack/netstack.go +++ b/pkg/sentry/socket/netstack/netstack.go @@ -26,6 +26,7 @@ package netstack import ( "bytes" + "fmt" "io" "math" "reflect" @@ -2468,6 +2469,23 @@ func (s *socketOpsCommon) fillCmsgInq(cmsg *socket.ControlMessages) { cmsg.IP.Inq = int32(len(s.readView) + rcvBufUsed) } +func toLinuxPacketType(pktType tcpip.PacketType) uint8 { + switch pktType { + case tcpip.PacketHost: + return linux.PACKET_HOST + case tcpip.PacketOtherHost: + return linux.PACKET_OTHERHOST + case tcpip.PacketOutgoing: + return linux.PACKET_OUTGOING + case tcpip.PacketBroadcast: + return linux.PACKET_BROADCAST + case tcpip.PacketMulticast: + return linux.PACKET_MULTICAST + default: + panic(fmt.Sprintf("unknown packet type: %d", pktType)) + } +} + // nonBlockingRead issues a non-blocking read. // // TODO(b/78348848): Support timestamps for stream sockets. @@ -2526,6 +2544,7 @@ func (s *socketOpsCommon) nonBlockingRead(ctx context.Context, dst usermem.IOSeq switch v := addr.(type) { case *linux.SockAddrLink: v.Protocol = htons(uint16(s.linkPacketInfo.Protocol)) + v.PacketType = toLinuxPacketType(s.linkPacketInfo.PktType) } } diff --git a/pkg/tcpip/link/channel/channel.go b/pkg/tcpip/link/channel/channel.go index a2bb773d4..e12a5929b 100644 --- a/pkg/tcpip/link/channel/channel.go +++ b/pkg/tcpip/link/channel/channel.go @@ -302,3 +302,7 @@ func (e *Endpoint) RemoveNotify(handle *NotificationHandle) { func (*Endpoint) ARPHardwareType() header.ARPHardwareType { return header.ARPHardwareNone } + +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { +} diff --git a/pkg/tcpip/link/fdbased/endpoint.go b/pkg/tcpip/link/fdbased/endpoint.go index 6aa1badc7..c18bb91fb 100644 --- a/pkg/tcpip/link/fdbased/endpoint.go +++ b/pkg/tcpip/link/fdbased/endpoint.go @@ -386,26 +386,33 @@ const ( _VIRTIO_NET_HDR_GSO_TCPV6 = 4 ) -// WritePacket writes outbound packets to the file descriptor. If it is not -// currently writable, the packet is dropped. -func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error { +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { if e.hdrSize > 0 { // Add ethernet header if needed. eth := header.Ethernet(pkt.Header.Prepend(header.EthernetMinimumSize)) pkt.LinkHeader = buffer.View(eth) ethHdr := &header.EthernetFields{ - DstAddr: r.RemoteLinkAddress, + DstAddr: remote, Type: protocol, } // Preserve the src address if it's set in the route. - if r.LocalLinkAddress != "" { - ethHdr.SrcAddr = r.LocalLinkAddress + if local != "" { + ethHdr.SrcAddr = local } else { ethHdr.SrcAddr = e.addr } eth.Encode(ethHdr) } +} + +// WritePacket writes outbound packets to the file descriptor. If it is not +// currently writable, the packet is dropped. +func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error { + if e.hdrSize > 0 { + e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt) + } var builder iovec.Builder @@ -448,22 +455,8 @@ func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tc // Send a batch of packets through batchFD. mmsgHdrs := make([]rawfile.MMsgHdr, 0, len(batch)) for _, pkt := range batch { - var eth header.Ethernet if e.hdrSize > 0 { - // Add ethernet header if needed. - eth = make(header.Ethernet, header.EthernetMinimumSize) - ethHdr := &header.EthernetFields{ - DstAddr: pkt.EgressRoute.RemoteLinkAddress, - Type: pkt.NetworkProtocolNumber, - } - - // Preserve the src address if it's set in the route. - if pkt.EgressRoute.LocalLinkAddress != "" { - ethHdr.SrcAddr = pkt.EgressRoute.LocalLinkAddress - } else { - ethHdr.SrcAddr = e.addr - } - eth.Encode(ethHdr) + e.AddHeader(pkt.EgressRoute.LocalLinkAddress, pkt.EgressRoute.RemoteLinkAddress, pkt.NetworkProtocolNumber, pkt) } var vnetHdrBuf []byte @@ -493,7 +486,6 @@ func (e *endpoint) sendBatch(batchFD int, batch []*stack.PacketBuffer) (int, *tc var builder iovec.Builder builder.Add(vnetHdrBuf) - builder.Add(eth) builder.Add(pkt.Header.View()) for _, v := range pkt.Data.Views() { builder.Add(v) diff --git a/pkg/tcpip/link/fdbased/endpoint_test.go b/pkg/tcpip/link/fdbased/endpoint_test.go index 4bad930c7..7b995b85a 100644 --- a/pkg/tcpip/link/fdbased/endpoint_test.go +++ b/pkg/tcpip/link/fdbased/endpoint_test.go @@ -107,6 +107,10 @@ func (c *context) DeliverNetworkPacket(remote tcpip.LinkAddress, local tcpip.Lin c.ch <- packetInfo{remote, protocol, pkt} } +func (c *context) DeliverOutboundPacket(remote tcpip.LinkAddress, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("unimplemented") +} + func TestNoEthernetProperties(t *testing.T) { c := newContext(t, &Options{MTU: mtu}) defer c.cleanup() @@ -510,6 +514,10 @@ func (d *fakeNetworkDispatcher) DeliverNetworkPacket(remote, local tcpip.LinkAdd d.pkts = append(d.pkts, pkt) } +func (d *fakeNetworkDispatcher) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("unimplemented") +} + func TestDispatchPacketFormat(t *testing.T) { for _, test := range []struct { name string diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go index 3b17d8c28..781cdd317 100644 --- a/pkg/tcpip/link/loopback/loopback.go +++ b/pkg/tcpip/link/loopback/loopback.go @@ -118,3 +118,6 @@ func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { func (*endpoint) ARPHardwareType() header.ARPHardwareType { return header.ARPHardwareLoopback } + +func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { +} diff --git a/pkg/tcpip/link/muxed/injectable.go b/pkg/tcpip/link/muxed/injectable.go index c305d9e86..56a611825 100644 --- a/pkg/tcpip/link/muxed/injectable.go +++ b/pkg/tcpip/link/muxed/injectable.go @@ -135,6 +135,10 @@ func (*InjectableEndpoint) ARPHardwareType() header.ARPHardwareType { panic("unsupported operation") } +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (*InjectableEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { +} + // NewInjectableEndpoint creates a new multi-endpoint injectable endpoint. func NewInjectableEndpoint(routes map[tcpip.Address]stack.InjectableLinkEndpoint) *InjectableEndpoint { return &InjectableEndpoint{ diff --git a/pkg/tcpip/link/nested/nested.go b/pkg/tcpip/link/nested/nested.go index 328bd048e..d40de54df 100644 --- a/pkg/tcpip/link/nested/nested.go +++ b/pkg/tcpip/link/nested/nested.go @@ -61,6 +61,16 @@ func (e *Endpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protoco } } +// DeliverOutboundPacket implements stack.NetworkDispatcher.DeliverOutboundPacket. +func (e *Endpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.mu.RLock() + d := e.dispatcher + e.mu.RUnlock() + if d != nil { + d.DeliverOutboundPacket(remote, local, protocol, pkt) + } +} + // Attach implements stack.LinkEndpoint. func (e *Endpoint) Attach(dispatcher stack.NetworkDispatcher) { e.mu.Lock() @@ -135,3 +145,8 @@ func (e *Endpoint) GSOMaxSize() uint32 { func (e *Endpoint) ARPHardwareType() header.ARPHardwareType { return e.child.ARPHardwareType() } + +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.child.AddHeader(local, remote, protocol, pkt) +} diff --git a/pkg/tcpip/link/nested/nested_test.go b/pkg/tcpip/link/nested/nested_test.go index c1a219f02..7d9249c1c 100644 --- a/pkg/tcpip/link/nested/nested_test.go +++ b/pkg/tcpip/link/nested/nested_test.go @@ -55,6 +55,10 @@ func (d *counterDispatcher) DeliverNetworkPacket(tcpip.LinkAddress, tcpip.LinkAd d.count++ } +func (d *counterDispatcher) DeliverOutboundPacket(tcpip.LinkAddress, tcpip.LinkAddress, tcpip.NetworkProtocolNumber, *stack.PacketBuffer) { + panic("unimplemented") +} + func TestNestedLinkEndpoint(t *testing.T) { const emptyAddress = tcpip.LinkAddress("") diff --git a/pkg/tcpip/link/packetsocket/BUILD b/pkg/tcpip/link/packetsocket/BUILD new file mode 100644 index 000000000..6fff160ce --- /dev/null +++ b/pkg/tcpip/link/packetsocket/BUILD @@ -0,0 +1,14 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "packetsocket", + srcs = ["endpoint.go"], + visibility = ["//visibility:public"], + deps = [ + "//pkg/tcpip", + "//pkg/tcpip/link/nested", + "//pkg/tcpip/stack", + ], +) diff --git a/pkg/tcpip/link/packetsocket/endpoint.go b/pkg/tcpip/link/packetsocket/endpoint.go new file mode 100644 index 000000000..3922c2a04 --- /dev/null +++ b/pkg/tcpip/link/packetsocket/endpoint.go @@ -0,0 +1,50 @@ +// 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 packetsocket provides a link layer endpoint that provides the ability +// to loop outbound packets to any AF_PACKET sockets that may be interested in +// the outgoing packet. +package packetsocket + +import ( + "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/link/nested" + "gvisor.dev/gvisor/pkg/tcpip/stack" +) + +type endpoint struct { + nested.Endpoint +} + +// New creates a new packetsocket LinkEndpoint. +func New(lower stack.LinkEndpoint) stack.LinkEndpoint { + e := &endpoint{} + e.Endpoint.Init(lower, e) + return e +} + +// WritePacket implements stack.LinkEndpoint.WritePacket. +func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error { + e.Endpoint.DeliverOutboundPacket(r.RemoteLinkAddress, r.LocalLinkAddress, protocol, pkt) + return e.Endpoint.WritePacket(r, gso, protocol, pkt) +} + +// WritePackets implements stack.LinkEndpoint.WritePackets. +func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.PacketBufferList, proto tcpip.NetworkProtocolNumber) (int, *tcpip.Error) { + for pkt := pkts.Front(); pkt != nil; pkt = pkt.Next() { + e.Endpoint.DeliverOutboundPacket(pkt.EgressRoute.RemoteLinkAddress, pkt.EgressRoute.LocalLinkAddress, pkt.NetworkProtocolNumber, pkt) + } + + return e.Endpoint.WritePackets(r, gso, pkts, proto) +} diff --git a/pkg/tcpip/link/qdisc/fifo/endpoint.go b/pkg/tcpip/link/qdisc/fifo/endpoint.go index c84fe1bb9..467083239 100644 --- a/pkg/tcpip/link/qdisc/fifo/endpoint.go +++ b/pkg/tcpip/link/qdisc/fifo/endpoint.go @@ -107,6 +107,11 @@ func (e *endpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protoco e.dispatcher.DeliverNetworkPacket(remote, local, protocol, pkt) } +// DeliverOutboundPacket implements stack.NetworkDispatcher.DeliverOutboundPacket. +func (e *endpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.dispatcher.DeliverOutboundPacket(remote, local, protocol, pkt) +} + // Attach implements stack.LinkEndpoint.Attach. func (e *endpoint) Attach(dispatcher stack.NetworkDispatcher) { e.dispatcher = dispatcher @@ -194,6 +199,8 @@ func (e *endpoint) WritePackets(_ *stack.Route, _ *stack.GSO, pkts stack.PacketB // WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket. func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { + // TODO(gvisor.dev/issue/3267/): Queue these packets as well once + // WriteRawPacket takes PacketBuffer instead of VectorisedView. return e.lower.WriteRawPacket(vv) } @@ -213,3 +220,8 @@ func (e *endpoint) Wait() { func (e *endpoint) ARPHardwareType() header.ARPHardwareType { return e.lower.ARPHardwareType() } + +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.lower.AddHeader(local, remote, protocol, pkt) +} diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go index a36862c67..507c76b76 100644 --- a/pkg/tcpip/link/sharedmem/sharedmem.go +++ b/pkg/tcpip/link/sharedmem/sharedmem.go @@ -183,22 +183,29 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress { return e.addr } -// WritePacket writes outbound packets to the file descriptor. If it is not -// currently writable, the packet is dropped. -func (e *endpoint) WritePacket(r *stack.Route, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error { - // Add the ethernet header here. +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + // Add ethernet header if needed. eth := header.Ethernet(pkt.Header.Prepend(header.EthernetMinimumSize)) pkt.LinkHeader = buffer.View(eth) ethHdr := &header.EthernetFields{ - DstAddr: r.RemoteLinkAddress, + DstAddr: remote, Type: protocol, } - if r.LocalLinkAddress != "" { - ethHdr.SrcAddr = r.LocalLinkAddress + + // Preserve the src address if it's set in the route. + if local != "" { + ethHdr.SrcAddr = local } else { ethHdr.SrcAddr = e.addr } eth.Encode(ethHdr) +} + +// WritePacket writes outbound packets to the file descriptor. If it is not +// currently writable, the packet is dropped. +func (e *endpoint) WritePacket(r *stack.Route, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error { + e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt) v := pkt.Data.ToView() // Transmit the packet. diff --git a/pkg/tcpip/link/sharedmem/sharedmem_test.go b/pkg/tcpip/link/sharedmem/sharedmem_test.go index 28a2e88ba..8f3cd9449 100644 --- a/pkg/tcpip/link/sharedmem/sharedmem_test.go +++ b/pkg/tcpip/link/sharedmem/sharedmem_test.go @@ -143,6 +143,10 @@ func (c *testContext) DeliverNetworkPacket(remoteLinkAddr, localLinkAddr tcpip.L c.packetCh <- struct{}{} } +func (c *testContext) DeliverOutboundPacket(remoteLinkAddr, localLinkAddr tcpip.LinkAddress, proto tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("unimplemented") +} + func (c *testContext) cleanup() { c.ep.Close() closeFDs(&c.txCfg) diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go index d9cd4e83a..509076643 100644 --- a/pkg/tcpip/link/sniffer/sniffer.go +++ b/pkg/tcpip/link/sniffer/sniffer.go @@ -123,6 +123,11 @@ func (e *endpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protoco e.Endpoint.DeliverNetworkPacket(remote, local, protocol, pkt) } +// DeliverOutboundPacket implements stack.NetworkDispatcher.DeliverOutboundPacket. +func (e *endpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.Endpoint.DeliverOutboundPacket(remote, local, protocol, pkt) +} + func (e *endpoint) dumpPacket(prefix string, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { writer := e.writer if writer == nil && atomic.LoadUint32(&LogPackets) == 1 { diff --git a/pkg/tcpip/link/tun/device.go b/pkg/tcpip/link/tun/device.go index 47446efec..04ae58e59 100644 --- a/pkg/tcpip/link/tun/device.go +++ b/pkg/tcpip/link/tun/device.go @@ -272,21 +272,9 @@ func (d *Device) encodePkt(info *channel.PacketInfo) (buffer.View, bool) { if d.hasFlags(linux.IFF_TAP) { // Add ethernet header if not provided. if info.Pkt.LinkHeader == nil { - hdr := &header.EthernetFields{ - SrcAddr: info.Route.LocalLinkAddress, - DstAddr: info.Route.RemoteLinkAddress, - Type: info.Proto, - } - if hdr.SrcAddr == "" { - hdr.SrcAddr = d.endpoint.LinkAddress() - } - - eth := make(header.Ethernet, header.EthernetMinimumSize) - eth.Encode(hdr) - vv.AppendView(buffer.View(eth)) - } else { - vv.AppendView(info.Pkt.LinkHeader) + d.endpoint.AddHeader(info.Route.LocalLinkAddress, info.Route.RemoteLinkAddress, info.Proto, info.Pkt) } + vv.AppendView(info.Pkt.LinkHeader) } // Append upper headers. @@ -366,3 +354,30 @@ func (e *tunEndpoint) ARPHardwareType() header.ARPHardwareType { } return header.ARPHardwareNone } + +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *tunEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + if !e.isTap { + return + } + eth := header.Ethernet(pkt.Header.Prepend(header.EthernetMinimumSize)) + pkt.LinkHeader = buffer.View(eth) + hdr := &header.EthernetFields{ + SrcAddr: local, + DstAddr: remote, + Type: protocol, + } + if hdr.SrcAddr == "" { + hdr.SrcAddr = e.LinkAddress() + } + + eth.Encode(hdr) +} + +// MaxHeaderLength returns the maximum size of the link layer header. +func (e *tunEndpoint) MaxHeaderLength() uint16 { + if e.isTap { + return header.EthernetMinimumSize + } + return 0 +} diff --git a/pkg/tcpip/link/waitable/waitable.go b/pkg/tcpip/link/waitable/waitable.go index 24a8dc2eb..b152a0f26 100644 --- a/pkg/tcpip/link/waitable/waitable.go +++ b/pkg/tcpip/link/waitable/waitable.go @@ -60,6 +60,15 @@ func (e *Endpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protoco e.dispatchGate.Leave() } +// DeliverOutboundPacket implements stack.NetworkDispatcher.DeliverOutboundPacket. +func (e *Endpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + if !e.dispatchGate.Enter() { + return + } + e.dispatcher.DeliverOutboundPacket(remote, local, protocol, pkt) + e.dispatchGate.Leave() +} + // Attach implements stack.LinkEndpoint.Attach. It saves the dispatcher and // registers with the lower endpoint as its dispatcher so that "e" is called // for inbound packets. @@ -153,3 +162,8 @@ func (e *Endpoint) Wait() {} func (e *Endpoint) ARPHardwareType() header.ARPHardwareType { return e.lower.ARPHardwareType() } + +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *Endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + e.lower.AddHeader(local, remote, protocol, pkt) +} diff --git a/pkg/tcpip/link/waitable/waitable_test.go b/pkg/tcpip/link/waitable/waitable_test.go index ffb2354be..c448a888f 100644 --- a/pkg/tcpip/link/waitable/waitable_test.go +++ b/pkg/tcpip/link/waitable/waitable_test.go @@ -40,6 +40,10 @@ func (e *countedEndpoint) DeliverNetworkPacket(remote, local tcpip.LinkAddress, e.dispatchCount++ } +func (e *countedEndpoint) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("unimplemented") +} + func (e *countedEndpoint) Attach(dispatcher stack.NetworkDispatcher) { e.attachCount++ e.dispatcher = dispatcher @@ -90,6 +94,11 @@ func (*countedEndpoint) ARPHardwareType() header.ARPHardwareType { // Wait implements stack.LinkEndpoint.Wait. func (*countedEndpoint) Wait() {} +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *countedEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("unimplemented") +} + func TestWaitWrite(t *testing.T) { ep := &countedEndpoint{} wep := New(ep) diff --git a/pkg/tcpip/network/ip_test.go b/pkg/tcpip/network/ip_test.go index a5b780ca2..615bae648 100644 --- a/pkg/tcpip/network/ip_test.go +++ b/pkg/tcpip/network/ip_test.go @@ -185,6 +185,11 @@ func (*testObject) ARPHardwareType() header.ARPHardwareType { panic("not implemented") } +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (*testObject) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) { + panic("not implemented") +} + func buildIPv4Route(local, remote tcpip.Address) (stack.Route, *tcpip.Error) { s := stack.New(stack.Options{ NetworkProtocols: []stack.NetworkProtocol{ipv4.NewProtocol()}, diff --git a/pkg/tcpip/stack/forwarder_test.go b/pkg/tcpip/stack/forwarder_test.go index eefb4b07f..bca1d940b 100644 --- a/pkg/tcpip/stack/forwarder_test.go +++ b/pkg/tcpip/stack/forwarder_test.go @@ -307,6 +307,11 @@ func (*fwdTestLinkEndpoint) ARPHardwareType() header.ARPHardwareType { panic("not implemented") } +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *fwdTestLinkEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) { + panic("not implemented") +} + func fwdTestNetFactory(t *testing.T, proto *fwdTestNetworkProtocol) (ep1, ep2 *fwdTestLinkEndpoint) { // Create a stack with the network protocol and two NICs. s := New(Options{ diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 7b80534e6..fea0ce7e8 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -1200,15 +1200,13 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp // Are any packet sockets listening for this network protocol? packetEPs := n.mu.packetEPs[protocol] - // Check whether there are packet sockets listening for every protocol. - // If we received a packet with protocol EthernetProtocolAll, then the - // previous for loop will have handled it. - if protocol != header.EthernetProtocolAll { - packetEPs = append(packetEPs, n.mu.packetEPs[header.EthernetProtocolAll]...) - } + // Add any other packet sockets that maybe listening for all protocols. + packetEPs = append(packetEPs, n.mu.packetEPs[header.EthernetProtocolAll]...) n.mu.RUnlock() for _, ep := range packetEPs { - ep.HandlePacket(n.id, local, protocol, pkt.Clone()) + p := pkt.Clone() + p.PktType = tcpip.PacketHost + ep.HandlePacket(n.id, local, protocol, p) } if netProto.Number() == header.IPv4ProtocolNumber || netProto.Number() == header.IPv6ProtocolNumber { @@ -1311,6 +1309,24 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp } } +// DeliverOutboundPacket implements NetworkDispatcher.DeliverOutboundPacket. +func (n *NIC) DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) { + n.mu.RLock() + // We do not deliver to protocol specific packet endpoints as on Linux + // only ETH_P_ALL endpoints get outbound packets. + // Add any other packet sockets that maybe listening for all protocols. + packetEPs := n.mu.packetEPs[header.EthernetProtocolAll] + n.mu.RUnlock() + for _, ep := range packetEPs { + p := pkt.Clone() + 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) + 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. // TODO(b/151227689): Avoid copying the packet when forwarding. We can do this diff --git a/pkg/tcpip/stack/nic_test.go b/pkg/tcpip/stack/nic_test.go index 3bc9fd831..c477e31d8 100644 --- a/pkg/tcpip/stack/nic_test.go +++ b/pkg/tcpip/stack/nic_test.go @@ -89,6 +89,11 @@ func (*testLinkEndpoint) ARPHardwareType() header.ARPHardwareType { panic("not implemented") } +// AddHeader implements stack.LinkEndpoint.AddHeader. +func (e *testLinkEndpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) { + panic("not implemented") +} + var _ NetworkEndpoint = (*testIPv6Endpoint)(nil) // An IPv6 NetworkEndpoint that throws away outgoing packets. diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go index e3556d5d2..5d6865e35 100644 --- a/pkg/tcpip/stack/packet_buffer.go +++ b/pkg/tcpip/stack/packet_buffer.go @@ -79,6 +79,10 @@ type PacketBuffer struct { // NatDone indicates if the packet has been manipulated as per NAT // iptables rule. NatDone bool + + // PktType indicates the SockAddrLink.PacketType of the packet as defined in + // https://www.man7.org/linux/man-pages/man7/packet.7.html. + PktType tcpip.PacketType } // Clone makes a copy of pk. It clones the Data field, which creates a new diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index f260eeb7f..cd4b7a449 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -330,8 +330,7 @@ type NetworkProtocol interface { } // NetworkDispatcher contains the methods used by the network stack to deliver -// packets to the appropriate network endpoint after it has been handled by -// the data link layer. +// inbound/outbound packets to the appropriate network/packet(if any) endpoints. type NetworkDispatcher interface { // DeliverNetworkPacket finds the appropriate network protocol endpoint // and hands the packet over for further processing. @@ -342,6 +341,16 @@ type NetworkDispatcher interface { // // DeliverNetworkPacket takes ownership of pkt. DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) + + // DeliverOutboundPacket is called by link layer when a packet is being + // sent out. + // + // pkt.LinkHeader may or may not be set before calling + // DeliverOutboundPacket. Some packets do not have link headers (e.g. + // packets sent via loopback), and won't have the field set. + // + // DeliverOutboundPacket takes ownership of pkt. + DeliverOutboundPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) } // LinkEndpointCapabilities is the type associated with the capabilities @@ -443,6 +452,9 @@ type LinkEndpoint interface { // See: // https://github.com/torvalds/linux/blob/aa0c9086b40c17a7ad94425b3b70dd1fdd7497bf/include/uapi/linux/if_arp.h#L30 ARPHardwareType() header.ARPHardwareType + + // AddHeader adds a link layer header to pkt if required. + AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) } // InjectableLinkEndpoint is a LinkEndpoint where inbound packets are diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index 48ad56d4d..ff14a3b3c 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -316,6 +316,28 @@ const ( ShutdownWrite ) +// PacketType is used to indicate the destination of the packet. +type PacketType uint8 + +const ( + // PacketHost indicates a packet addressed to the local host. + PacketHost PacketType = iota + + // PacketOtherHost indicates an outgoing packet addressed to + // another host caught by a NIC in promiscuous mode. + PacketOtherHost + + // PacketOutgoing for a packet originating from the local host + // that is looped back to a packet socket. + PacketOutgoing + + // PacketBroadcast indicates a link layer broadcast packet. + PacketBroadcast + + // PacketMulticast indicates a link layer multicast packet. + PacketMulticast +) + // FullAddress represents a full transport node address, as required by the // Connect() and Bind() methods. // @@ -555,6 +577,9 @@ type Endpoint interface { type LinkPacketInfo struct { // Protocol is the NetworkProtocolNumber for the packet. Protocol NetworkProtocolNumber + + // PktType is used to indicate the destination of the packet. + PktType PacketType } // PacketEndpoint are additional methods that are only implemented by Packet diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go index 7b2083a09..8f167391f 100644 --- a/pkg/tcpip/transport/packet/endpoint.go +++ b/pkg/tcpip/transport/packet/endpoint.go @@ -441,6 +441,7 @@ func (ep *endpoint) HandlePacket(nicID tcpip.NICID, localAddr tcpip.LinkAddress, Addr: tcpip.Address(hdr.SourceAddress()), } packet.packetInfo.Protocol = netProto + packet.packetInfo.PktType = pkt.PktType } else { // Guess the would-be ethernet header. packet.senderAddr = tcpip.FullAddress{ @@ -448,30 +449,53 @@ func (ep *endpoint) HandlePacket(nicID tcpip.NICID, localAddr tcpip.LinkAddress, Addr: tcpip.Address(localAddr), } packet.packetInfo.Protocol = netProto + packet.packetInfo.PktType = pkt.PktType } if ep.cooked { // Cooked packets can simply be queued. - packet.data = pkt.Data + switch pkt.PktType { + case tcpip.PacketHost: + packet.data = pkt.Data + case tcpip.PacketOutgoing: + // Strip Link Header from the Header. + pkt.Header = buffer.NewPrependableFromView(pkt.Header.View()[len(pkt.LinkHeader):]) + combinedVV := pkt.Header.View().ToVectorisedView() + combinedVV.Append(pkt.Data) + packet.data = combinedVV + default: + panic(fmt.Sprintf("unexpected PktType in pkt: %+v", pkt)) + } + } else { // Raw packets need their ethernet headers prepended before // queueing. var linkHeader buffer.View - if len(pkt.LinkHeader) == 0 { - // We weren't provided with an actual ethernet header, - // so fake one. - ethFields := header.EthernetFields{ - SrcAddr: tcpip.LinkAddress([]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}), - DstAddr: localAddr, - Type: netProto, + var combinedVV buffer.VectorisedView + if pkt.PktType != tcpip.PacketOutgoing { + if len(pkt.LinkHeader) == 0 { + // We weren't provided with an actual ethernet header, + // so fake one. + ethFields := header.EthernetFields{ + SrcAddr: tcpip.LinkAddress([]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}), + DstAddr: localAddr, + Type: netProto, + } + fakeHeader := make(header.Ethernet, header.EthernetMinimumSize) + fakeHeader.Encode(ðFields) + linkHeader = buffer.View(fakeHeader) + } else { + linkHeader = append(buffer.View(nil), pkt.LinkHeader...) } - fakeHeader := make(header.Ethernet, header.EthernetMinimumSize) - fakeHeader.Encode(ðFields) - linkHeader = buffer.View(fakeHeader) - } else { - linkHeader = append(buffer.View(nil), pkt.LinkHeader...) + combinedVV = linkHeader.ToVectorisedView() + } + if pkt.PktType == tcpip.PacketOutgoing { + // For outgoing packets the Link, Network and Transport + // headers are in the pkt.Header fields normally unless + // a Raw socket is in use in which case pkt.Header could + // be nil. + combinedVV.AppendView(pkt.Header.View()) } - combinedVV := linkHeader.ToVectorisedView() combinedVV.Append(pkt.Data) packet.data = combinedVV } |