From 9d148627f82f4325b499e023c5cbf8afd5f988f6 Mon Sep 17 00:00:00 2001 From: Bruno Dal Bo Date: Wed, 18 Nov 2020 07:03:02 -0800 Subject: Introduce stack.WritePacketToRemote, remove LinkEndpoint.WriteRawPacket Redefine stack.WritePacket into stack.WritePacketToRemote which lets the NIC decide whether to append link headers. PiperOrigin-RevId: 343071742 --- pkg/tcpip/stack/forwarding_test.go | 14 --------- pkg/tcpip/stack/registration.go | 4 --- pkg/tcpip/stack/stack.go | 45 +++++----------------------- pkg/tcpip/stack/stack_test.go | 60 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 68 insertions(+), 55 deletions(-) (limited to 'pkg/tcpip/stack') diff --git a/pkg/tcpip/stack/forwarding_test.go b/pkg/tcpip/stack/forwarding_test.go index 6dc9e7859..cb7dec1ea 100644 --- a/pkg/tcpip/stack/forwarding_test.go +++ b/pkg/tcpip/stack/forwarding_test.go @@ -333,20 +333,6 @@ func (e *fwdTestLinkEndpoint) WritePackets(r *Route, gso *GSO, pkts PacketBuffer return n, nil } -// WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket. -func (e *fwdTestLinkEndpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { - p := fwdTestPacketInfo{ - Pkt: NewPacketBuffer(PacketBufferOptions{Data: vv}), - } - - select { - case e.C <- p: - default: - } - - return nil -} - // Wait implements stack.LinkEndpoint.Wait. func (*fwdTestLinkEndpoint) Wait() {} diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index 2cb13c6fa..43ca03ada 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -739,10 +739,6 @@ type LinkEndpoint interface { // endpoint. Capabilities() LinkEndpointCapabilities - // WriteRawPacket writes a packet directly to the link. The packet - // should already have an ethernet header. It takes ownership of vv. - WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error - // Attach attaches the data link layer endpoint to the network-layer // dispatcher of the stack. // diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index e0025e0a9..f4504e633 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -1810,49 +1810,20 @@ func (s *Stack) unregisterPacketEndpointLocked(nicID tcpip.NICID, netProto tcpip nic.unregisterPacketEndpoint(netProto, ep) } -// WritePacket writes data directly to the specified NIC. It adds an ethernet -// header based on the arguments. -func (s *Stack) WritePacket(nicID tcpip.NICID, dst tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, payload buffer.VectorisedView) *tcpip.Error { +// WritePacketToRemote writes a payload on the specified NIC using the provided +// network protocol and remote link address. +func (s *Stack) WritePacketToRemote(nicID tcpip.NICID, remote tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, payload buffer.VectorisedView) *tcpip.Error { s.mu.Lock() nic, ok := s.nics[nicID] s.mu.Unlock() if !ok { return tcpip.ErrUnknownDevice } - - // Add our own fake ethernet header. - ethFields := header.EthernetFields{ - SrcAddr: nic.LinkEndpoint.LinkAddress(), - DstAddr: dst, - Type: netProto, - } - fakeHeader := make(header.Ethernet, header.EthernetMinimumSize) - fakeHeader.Encode(ðFields) - vv := buffer.View(fakeHeader).ToVectorisedView() - vv.Append(payload) - - if err := nic.LinkEndpoint.WriteRawPacket(vv); err != nil { - return err - } - - return nil -} - -// WriteRawPacket writes data directly to the specified NIC without adding any -// headers. -func (s *Stack) WriteRawPacket(nicID tcpip.NICID, payload buffer.VectorisedView) *tcpip.Error { - s.mu.Lock() - nic, ok := s.nics[nicID] - s.mu.Unlock() - if !ok { - return tcpip.ErrUnknownDevice - } - - if err := nic.LinkEndpoint.WriteRawPacket(payload); err != nil { - return err - } - - return nil + pkt := NewPacketBuffer(PacketBufferOptions{ + ReserveHeaderBytes: int(nic.MaxHeaderLength()), + Data: payload, + }) + return nic.WritePacketToRemote(remote, nil, netProto, pkt) } // NetworkProtocolInstance returns the protocol instance in the stack for the diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index 61db3164b..0d94af139 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -4152,3 +4152,63 @@ func TestFindRouteWithForwarding(t *testing.T) { }) } } + +func TestWritePacketToRemote(t *testing.T) { + const nicID = 1 + const MTU = 1280 + e := channel.New(1, MTU, linkAddr1) + s := stack.New(stack.Options{}) + if err := s.CreateNIC(nicID, e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) + } + if err := s.EnableNIC(nicID); err != nil { + t.Fatalf("CreateNIC(%d) = %s", nicID, err) + } + tests := []struct { + name string + protocol tcpip.NetworkProtocolNumber + payload []byte + }{ + { + name: "SuccessIPv4", + protocol: header.IPv4ProtocolNumber, + payload: []byte{1, 2, 3, 4}, + }, + { + name: "SuccessIPv6", + protocol: header.IPv6ProtocolNumber, + payload: []byte{5, 6, 7, 8}, + }, + } + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + if err := s.WritePacketToRemote(nicID, linkAddr2, test.protocol, buffer.View(test.payload).ToVectorisedView()); err != nil { + t.Fatalf("s.WritePacketToRemote(_, _, _, _) = %s", err) + } + + pkt, ok := e.Read() + if got, want := ok, true; got != want { + t.Fatalf("e.Read() = %t, want %t", got, want) + } + if got, want := pkt.Proto, test.protocol; got != want { + t.Fatalf("pkt.Proto = %d, want %d", got, want) + } + if got, want := pkt.Route.RemoteLinkAddress, linkAddr2; got != want { + t.Fatalf("pkt.Route.RemoteAddress = %s, want %s", got, want) + } + if diff := cmp.Diff(pkt.Pkt.Data.ToView(), buffer.View(test.payload)); diff != "" { + t.Errorf("pkt.Pkt.Data mismatch (-want +got):\n%s", diff) + } + }) + } + + t.Run("InvalidNICID", func(t *testing.T) { + if got, want := s.WritePacketToRemote(234, linkAddr2, header.IPv4ProtocolNumber, buffer.View([]byte{1}).ToVectorisedView()), tcpip.ErrUnknownDevice; got != want { + t.Fatalf("s.WritePacketToRemote(_, _, _, _) = %s, want = %s", got, want) + } + pkt, ok := e.Read() + if got, want := ok, false; got != want { + t.Fatalf("e.Read() = %t, %v; want %t", got, pkt, want) + } + }) +} -- cgit v1.2.3