diff options
Diffstat (limited to 'pkg/tcpip/transport/udp')
| -rw-r--r-- | pkg/tcpip/transport/udp/endpoint.go | 1 | ||||
| -rw-r--r-- | pkg/tcpip/transport/udp/protocol.go | 117 | ||||
| -rw-r--r-- | pkg/tcpip/transport/udp/udp_test.go | 4 |
3 files changed, 11 insertions, 111 deletions
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index 518f636f0..086d0bdbc 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -996,6 +996,7 @@ func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort u // Initialize the UDP header. udp := header.UDP(pkt.TransportHeader().Push(header.UDPMinimumSize)) + pkt.TransportProtocolNumber = ProtocolNumber length := uint16(pkt.Size()) udp.Encode(&header.UDPFields{ diff --git a/pkg/tcpip/transport/udp/protocol.go b/pkg/tcpip/transport/udp/protocol.go index 7d6b91a75..a1d0f49d9 100644 --- a/pkg/tcpip/transport/udp/protocol.go +++ b/pkg/tcpip/transport/udp/protocol.go @@ -80,126 +80,21 @@ func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) { return h.SourcePort(), h.DestinationPort(), nil } -// HandleUnknownDestinationPacket handles packets targeted at this protocol but -// that don't match any existing endpoint. -func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt *stack.PacketBuffer) bool { +// HandleUnknownDestinationPacket handles packets that are targeted at this +// protocol but don't match any existing endpoint. +func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt *stack.PacketBuffer) stack.UnknownDestinationPacketDisposition { hdr := header.UDP(pkt.TransportHeader().View()) if int(hdr.Length()) > pkt.Data.Size()+header.UDPMinimumSize { - // Malformed packet. r.Stack().Stats().UDP.MalformedPacketsReceived.Increment() - return true + return stack.UnknownDestinationPacketMalformed } if !verifyChecksum(r, hdr, pkt) { - // Checksum Error. r.Stack().Stats().UDP.ChecksumErrors.Increment() - return true + return stack.UnknownDestinationPacketMalformed } - // Only send ICMP error if the address is not a multicast/broadcast - // v4/v6 address or the source is not the unspecified address. - // - // See: point e) in https://tools.ietf.org/html/rfc4443#section-2.4 - if id.LocalAddress == header.IPv4Broadcast || header.IsV4MulticastAddress(id.LocalAddress) || header.IsV6MulticastAddress(id.LocalAddress) || id.RemoteAddress == header.IPv6Any || id.RemoteAddress == header.IPv4Any { - return true - } - - // As per RFC: 1122 Section 3.2.2.1 A host SHOULD generate Destination - // Unreachable messages with code: - // - // 2 (Protocol Unreachable), when the designated transport protocol - // is not supported; or - // - // 3 (Port Unreachable), when the designated transport protocol - // (e.g., UDP) is unable to demultiplex the datagram but has no - // protocol mechanism to inform the sender. - switch len(id.LocalAddress) { - case header.IPv4AddressSize: - if !r.Stack().AllowICMPMessage() { - r.Stack().Stats().ICMP.V4PacketsSent.RateLimited.Increment() - return true - } - // As per RFC 1812 Section 4.3.2.3 - // - // ICMP datagram SHOULD contain as much of the original - // datagram as possible without the length of the ICMP - // datagram exceeding 576 bytes - // - // NOTE: The above RFC referenced is different from the original - // recommendation in RFC 1122 where it mentioned that at least 8 - // bytes of the payload must be included. Today linux and other - // systems implement the] RFC1812 definition and not the original - // RFC 1122 requirement. - mtu := int(r.MTU()) - if mtu > header.IPv4MinimumProcessableDatagramSize { - mtu = header.IPv4MinimumProcessableDatagramSize - } - headerLen := int(r.MaxHeaderLength()) + header.ICMPv4MinimumSize - available := int(mtu) - headerLen - payloadLen := pkt.NetworkHeader().View().Size() + pkt.TransportHeader().View().Size() + pkt.Data.Size() - if payloadLen > available { - payloadLen = available - } - - // The buffers used by pkt may be used elsewhere in the system. - // For example, a raw or packet socket may use what UDP - // considers an unreachable destination. Thus we deep copy pkt - // to prevent multiple ownership and SR errors. - newHeader := append(buffer.View(nil), pkt.NetworkHeader().View()...) - newHeader = append(newHeader, pkt.TransportHeader().View()...) - payload := newHeader.ToVectorisedView() - payload.AppendView(pkt.Data.ToView()) - payload.CapLength(payloadLen) - - icmpPkt := stack.NewPacketBuffer(stack.PacketBufferOptions{ - ReserveHeaderBytes: headerLen, - Data: payload, - }) - icmpHdr := header.ICMPv4(icmpPkt.TransportHeader().Push(header.ICMPv4MinimumSize)) - icmpHdr.SetType(header.ICMPv4DstUnreachable) - icmpHdr.SetCode(header.ICMPv4PortUnreachable) - icmpHdr.SetChecksum(header.ICMPv4Checksum(icmpHdr, icmpPkt.Data)) - r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv4ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, icmpPkt) - - case header.IPv6AddressSize: - if !r.Stack().AllowICMPMessage() { - r.Stack().Stats().ICMP.V6PacketsSent.RateLimited.Increment() - return true - } - - // As per RFC 4443 section 2.4 - // - // (c) Every ICMPv6 error message (type < 128) MUST include - // as much of the IPv6 offending (invoking) packet (the - // packet that caused the error) as possible without making - // the error message packet exceed the minimum IPv6 MTU - // [IPv6]. - mtu := int(r.MTU()) - if mtu > header.IPv6MinimumMTU { - mtu = header.IPv6MinimumMTU - } - headerLen := int(r.MaxHeaderLength()) + header.ICMPv6DstUnreachableMinimumSize - available := int(mtu) - headerLen - network, transport := pkt.NetworkHeader().View(), pkt.TransportHeader().View() - payloadLen := len(network) + len(transport) + pkt.Data.Size() - if payloadLen > available { - payloadLen = available - } - payload := buffer.NewVectorisedView(len(network)+len(transport), []buffer.View{network, transport}) - payload.Append(pkt.Data) - payload.CapLength(payloadLen) - - icmpPkt := stack.NewPacketBuffer(stack.PacketBufferOptions{ - ReserveHeaderBytes: headerLen, - Data: payload, - }) - icmpHdr := header.ICMPv6(icmpPkt.TransportHeader().Push(header.ICMPv6DstUnreachableMinimumSize)) - icmpHdr.SetType(header.ICMPv6DstUnreachable) - icmpHdr.SetCode(header.ICMPv6PortUnreachable) - icmpHdr.SetChecksum(header.ICMPv6Checksum(icmpHdr, r.LocalAddress, r.RemoteAddress, icmpPkt.Data)) - r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, icmpPkt) - } - return true + return stack.UnknownDestinationPacketUnhandled } // SetOption implements stack.TransportProtocol.SetOption. diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go index d5881d183..64a5fc696 100644 --- a/pkg/tcpip/transport/udp/udp_test.go +++ b/pkg/tcpip/transport/udp/udp_test.go @@ -388,6 +388,10 @@ func (c *testContext) getPacketAndVerify(flow testFlow, checkers ...checker.Netw c.t.Fatalf("Bad network protocol: got %v, wanted %v", p.Proto, flow.netProto()) } + if got, want := p.Pkt.TransportProtocolNumber, header.UDPProtocolNumber; got != want { + c.t.Errorf("got p.Pkt.TransportProtocolNumber = %d, want = %d", got, want) + } + vv := buffer.NewVectorisedView(p.Pkt.Size(), p.Pkt.Views()) b := vv.ToView() |