From: Wilson Peng <[email protected]> While testing OVS-windows flows for the DNAT action, the checksum In TCP header is set incorrectly when TCP offload is enabled by Default. As a result, the packet will be dropped on receiver linuxVM.
>>>sample flow default configuration on both Windows VM and Linux VM (src=40.0.1.2,dst=10.150.0.1) --dnat--> (src=40.0.1.2,dst==30.1.0.2) Without the fix for some TCP packet(40.0.1.2->30.1.0.2 with payload len 207) the TCP checksum will be pseduo header checksum and the value is 0x01d6. With the fix the checksum will be 0x47ee, it could be got the correct TCP checksum on the receiver Linux VM. Signed-off-by: Wilson Peng<[email protected]> Signed-off-by: Anand Kumar<[email protected]> --- datapath-windows/ovsext/Actions.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/datapath-windows/ovsext/Actions.c b/datapath-windows/ovsext/Actions.c index 4f43369..e130c2f 100644 --- a/datapath-windows/ovsext/Actions.c +++ b/datapath-windows/ovsext/Actions.c @@ -1550,9 +1550,21 @@ OvsUpdateAddressAndPort(OvsForwardingContext *ovsFwdCtx, if (tcpHdr) { portField = &tcpHdr->dest; checkField = &tcpHdr->check; + l4Offload = isTx ? (BOOLEAN)csumInfo.Transmit.TcpChecksum : + ((BOOLEAN)csumInfo.Receive.TcpChecksumSucceeded || + (BOOLEAN)csumInfo.Receive.TcpChecksumFailed); } else if (udpHdr) { portField = &udpHdr->dest; checkField = &udpHdr->check; + l4Offload = isTx ? (BOOLEAN)csumInfo.Transmit.UdpChecksum : + ((BOOLEAN)csumInfo.Receive.UdpChecksumSucceeded || + (BOOLEAN)csumInfo.Receive.UdpChecksumFailed); + } + + if (l4Offload) { + *checkField = IPPseudoChecksum(&ipHdr->saddr, &newAddr, + tcpHdr ? IPPROTO_TCP : IPPROTO_UDP, + ntohs(ipHdr->tot_len) - ipHdr->ihl * 4); } } -- 2.9.3.windows.1 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
