diff options
Diffstat (limited to 'pkg/tcpip/transport/udp')
| -rw-r--r-- | pkg/tcpip/transport/udp/endpoint.go | 34 |
1 files changed, 21 insertions, 13 deletions
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index 956da0e0c..f26c7ca10 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -1255,20 +1255,29 @@ func (e *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask { } // verifyChecksum verifies the checksum unless RX checksum offload is enabled. -// On IPv4, UDP checksum is optional, and a zero value means the transmitter -// omitted the checksum generation (RFC768). -// On IPv6, UDP checksum is not optional (RFC2460 Section 8.1). func verifyChecksum(hdr header.UDP, pkt *stack.PacketBuffer) bool { - if !pkt.RXTransportChecksumValidated && - (hdr.Checksum() != 0 || pkt.NetworkProtocolNumber == header.IPv6ProtocolNumber) { - netHdr := pkt.Network() - xsum := header.PseudoHeaderChecksum(ProtocolNumber, netHdr.DestinationAddress(), netHdr.SourceAddress(), hdr.Length()) - for _, v := range pkt.Data().Views() { - xsum = header.Checksum(v, xsum) - } - return hdr.CalculateChecksum(xsum) == 0xffff + if pkt.RXTransportChecksumValidated { + return true + } + + // On IPv4, UDP checksum is optional, and a zero value means the transmitter + // omitted the checksum generation, as per RFC 768: + // + // An all zero transmitted checksum value means that the transmitter + // generated no checksum (for debugging or for higher level protocols that + // don't care). + // + // On IPv6, UDP checksum is not optional, as per RFC 2460 Section 8.1: + // + // Unlike IPv4, when UDP packets are originated by an IPv6 node, the UDP + // checksum is not optional. + if pkt.NetworkProtocolNumber == header.IPv4ProtocolNumber && hdr.Checksum() == 0 { + return true } - return true + + netHdr := pkt.Network() + payloadChecksum := pkt.Data().AsRange().Checksum() + return hdr.IsChecksumValid(netHdr.SourceAddress(), netHdr.DestinationAddress(), payloadChecksum) } // HandlePacket is called by the stack when new packets arrive to this transport @@ -1284,7 +1293,6 @@ func (e *endpoint) HandlePacket(id stack.TransportEndpointID, pkt *stack.PacketB } if !verifyChecksum(hdr, pkt) { - // Checksum Error. e.stack.Stats().UDP.ChecksumErrors.Increment() e.stats.ReceiveErrors.ChecksumErrors.Increment() return |