You are right Sai, the flags need to be set before the checksum is computed.
I acked you patch. Alin. > -----Mesaj original----- > De la: Sairam Venugopal [mailto:vsai...@vmware.com] > Trimis: Friday, February 26, 2016 12:56 AM > Către: Sorin Vinturis <svintu...@cloudbasesolutions.com>; > dev@openvswitch.org > Cc: Alin Serdean <aserd...@cloudbasesolutions.com> > Subiect: Re: [ovs-dev] [PATCH] datapath-windows: Support for IPv6 in TCP > segmentation. > > Hi Sorin/Alin, > > I tested out the patch and it seems to break existing checksum calculation. I > will send out a patch with changes that I did on top of Sorin¹s. I tested it > out > and could send TCP packets using IPv4 and IPv6. > > I believe this patch is in regards to the issue I reported earlier - > https://github.com/openvswitch/ovs-issues/issues/105 > > Thanks, > Sairam > > On 2/18/16, 3:08 AM, "Sorin Vinturis" <svintu...@cloudbasesolutions.com> > wrote: > > >When a packet which needs segmentation is received, the header for each > >segment is being calculated, i.e. IP length, checksum, TCP seq, TCP > >checksum. > > > >The problem with the current code is that it wrongly assumes that the > >Ethernet frame payload is always an IPv4 packet. > > > >This patch checks the EtherType field of the Ethernet frame to see > >which protocol is encapsulated in its payload, IPv4 or IPv6, and > >calculates accordingly the segment's header. > > > >Signed-off-by: Sorin Vinturis <svintu...@cloudbasesolutions.com> > >--- > > datapath-windows/ovsext/BufferMgmt.c | 91 > >++++++++++++++++++++++++------------ > > 1 file changed, 62 insertions(+), 29 deletions(-) > > > >diff --git a/datapath-windows/ovsext/BufferMgmt.c > >b/datapath-windows/ovsext/BufferMgmt.c > >index 3189e9b..085a551 100644 > >--- a/datapath-windows/ovsext/BufferMgmt.c > >+++ b/datapath-windows/ovsext/BufferMgmt.c > >@@ -1122,11 +1122,10 @@ static NDIS_STATUS > >FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 > seqNumber, > > BOOLEAN lastPacket, UINT16 packetCounter) { > >- EthHdr *dstEth; > >- IPHdr *dstIP; > >- TCPHdr *dstTCP; > >- PMDL mdl; > >- PUINT8 bufferStart; > >+ EthHdr *dstEth = NULL; > >+ TCPHdr *dstTCP = NULL; > >+ PMDL mdl = NULL; > >+ PUINT8 bufferStart = NULL; > > > > mdl = NET_BUFFER_FIRST_MDL(nb); > > > >@@ -1135,21 +1134,64 @@ FixSegmentHeader(PNET_BUFFER nb, UINT16 > >segmentSize, UINT32 seqNumber, > > return NDIS_STATUS_RESOURCES; > > } > > dstEth = (EthHdr *)(bufferStart + > NET_BUFFER_CURRENT_MDL_OFFSET(nb)); > >- ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >- >= sizeof(EthHdr) + sizeof(IPHdr) + sizeof(TCPHdr)); > >- dstIP = (IPHdr *)((PCHAR)dstEth + sizeof *dstEth); > >- dstTCP = (TCPHdr *)((PCHAR)dstIP + dstIP->ihl * 4); > >- ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >- >= sizeof(EthHdr) + dstIP->ihl * 4 + TCP_HDR_LEN(dstTCP)); > >- > >- /* Fix IP length and checksum */ > >- ASSERT(dstIP->protocol == IPPROTO_TCP); > >- dstIP->tot_len = htons(segmentSize + dstIP->ihl * 4 + > >TCP_HDR_LEN(dstTCP)); > >- dstIP->id += packetCounter; > >- dstIP->check = 0; > >- dstIP->check = IPChecksum((UINT8 *)dstIP, dstIP->ihl * 4, 0); > >- > >- /* Fix TCP checksum */ > >+ > >+ switch (dstEth->Type) { > >+ case ETH_TYPE_IPV4_NBO: > >+ { > >+ IPHdr *dstIP = NULL; > >+ > >+ ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >+ >= sizeof(EthHdr) + sizeof(IPHdr) + sizeof(TCPHdr)); > >+ dstIP = (IPHdr *)((PCHAR)dstEth + sizeof(*dstEth)); > >+ dstTCP = (TCPHdr *)((PCHAR)dstIP + dstIP->ihl * 4); > >+ ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >+ >= sizeof(EthHdr) + dstIP->ihl * 4 + > >TCP_HDR_LEN(dstTCP)); > >+ > >+ /* Fix IP length and checksum */ > >+ ASSERT(dstIP->protocol == IPPROTO_TCP); > >+ dstIP->tot_len = htons(segmentSize + dstIP->ihl * 4 + > >TCP_HDR_LEN(dstTCP)); > >+ dstIP->id += packetCounter; > >+ dstIP->check = IPChecksum((UINT8 *)dstIP, dstIP->ihl * 4, 0); > >+ > >+ /* Fix TCP checksum */ > >+ UINT16 csumLength = segmentSize + TCP_HDR_LEN(dstTCP); > >+ dstTCP->check = IPPseudoChecksum(&dstIP->saddr, > >+ &dstIP->daddr, > >+ IPPROTO_TCP, > >+ csumLength); > >+ dstTCP->check = CalculateChecksumNB(nb, > >+ csumLength, > >+ sizeof(*dstEth) + > >+ dstIP->ihl > >* 4); > >+ break; > >+ } > >+ case ETH_TYPE_IPV6_NBO: > >+ { > >+ IPv6Hdr *dstIP = NULL; > >+ > >+ ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >+ >= sizeof(EthHdr) + sizeof(IPv6Hdr) + sizeof(TCPHdr)); > >+ dstIP = (IPv6Hdr *)((PCHAR)dstEth + sizeof(*dstEth)); > >+ dstTCP = (TCPHdr *)((PCHAR)dstIP + sizeof(IPv6Hdr)); > >+ ASSERT((INT)MmGetMdlByteCount(mdl) - > >NET_BUFFER_CURRENT_MDL_OFFSET(nb) > >+ >= sizeof(EthHdr) + sizeof(IPv6Hdr) + > >+ TCP_HDR_LEN(dstTCP)); > >+ > >+ /* Fix IP length */ > >+ ASSERT(dstIP->nexthdr == IPPROTO_TCP); > >+ dstIP->payload_len = htons(segmentSize + sizeof(IPv6Hdr) + > >TCP_HDR_LEN(dstTCP)); > >+ > >+ /* Fix TCP checksum */ > >+ UINT16 csumLength = segmentSize + TCP_HDR_LEN(dstTCP); > >+ dstTCP->check = IPv6PseudoChecksum((UINT32*)&dstIP->saddr, > >+ (UINT32*)&dstIP->daddr, > >+ IPPROTO_TCP, > >+ csumLength); > >+ dstTCP->check = CalculateChecksumNB(nb, > >+ csumLength, > >+ sizeof(*dstEth) + > >sizeof(IPv6Hdr)); > >+ break; > >+ } > >+ } > >+ > > dstTCP->seq = htonl(seqNumber); > > > > /* > >@@ -1164,15 +1206,6 @@ FixSegmentHeader(PNET_BUFFER nb, UINT16 > >segmentSize, UINT32 seqNumber, > > dstTCP->psh = lastPacket; > > } > > > >- UINT16 csumLength = segmentSize + TCP_HDR_LEN(dstTCP); > >- dstTCP->check = IPPseudoChecksum(&dstIP->saddr, > >- &dstIP->daddr, > >- IPPROTO_TCP, > >- csumLength); > >- dstTCP->check = CalculateChecksumNB(nb, > >- csumLength, > >- sizeof *dstEth + dstIP->ihl * 4); > >- > > return STATUS_SUCCESS; > > } > > > >-- > >1.9.0.msysgit.0 > >_______________________________________________ > >dev mailing list > >dev@openvswitch.org > >https://urldefense.proofpoint.com/v2/url?u=http- > 3A__openvswitch.org_mai > >lma > >n_listinfo_dev&d=BQIGaQ&c=Sqcl0Ez6M0X8aeM67LKIiDJAXVeAw- > YihVMNtXt-uEs&r > >=Dc > >ruz40PROJ40ROzSpxyQSLw6fcrOWpJgEcEmNR3JEQ&m=E9U6eKBsuYHgHjK7 > -hEEVbGHhT1 > >gD6 - > FaMMkV95KXMw&s=NXpotbyxWn81PBmzYgR9N9Q8itBskCUcrItdbSB0MUs > &e= _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
