/*
* --------------------------------------------------------------------------
* FixSegmentHeader
*
* Fix IP length, IP checksum, TCP sequence number and TCP checksum
* in the segment.
* --------------------------------------------------------------------------
*/
static NDIS_STATUS
FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber)
{
EthHdr *dstEth;
IPHdr *dstIP;
TCPHdr *dstTCP;
PMDL mdl;
PUINT8 bufferStart;
mdl = NET_BUFFER_FIRST_MDL(nb);
bufferStart = (PUINT8)MmGetSystemAddressForMdlSafe(mdl, LowPagePriority);
if (!bufferStart) {
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->check = 0;
dstIP->check = IPChecksum((UINT8 *)dstIP, dstIP->ihl * 4, 0);
/* Fix TCP checksum */
dstTCP->seq = htonl(seqNumber);
dstTCP->check =
IPPseudoChecksum((UINT32 *)&dstIP->saddr,
(UINT32 *)&dstIP->daddr,
IPPROTO_TCP, segmentSize + TCP_HDR_LEN(dstTCP));
dstTCP->check = CalculateChecksumNB(nb,
(UINT16)(NET_BUFFER_DATA_LENGTH(nb) - sizeof *dstEth - dstIP->ihl * 4),
sizeof *dstEth + dstIP->ihl * 4);
return STATUS_SUCCESS;
}
/*
*----------------------------------------------------------------------------
* OvsDoEncapVxlan
* Encapsulates the packet.
*----------------------------------------------------------------------------
*/
static __inline NDIS_STATUS
OvsDoEncapVxlan(PNET_BUFFER_LIST curNbl,
OvsIPv4TunnelKey *tunKey,
POVS_FWD_INFO fwdInfo,
POVS_PACKET_HDR_INFO layers,
POVS_SWITCH_CONTEXT switchContext,
PNET_BUFFER_LIST *newNbl)
{
NDIS_STATUS status;
PNET_BUFFER curNb;
PMDL curMdl;
PUINT8 bufferStart;
EthHdr *ethHdr;
IPHdr *ipHdr;
UDPHdr *udpHdr;
VXLANHdr *vxlanHdr;
UINT32 headRoom = OvsGetVxlanTunHdrSize();
UINT32 packetLength;
/*
* XXX: the assumption currently is that the NBL is owned by OVS, and
* headroom has already been allocated as part of allocating the NBL and
* MDL.
*/
curNb = NET_BUFFER_LIST_FIRST_NB(curNbl);
packetLength = NET_BUFFER_DATA_LENGTH(curNb);
if (layers->isTcp) {
NDIS_TCP_LARGE_SEND_OFFLOAD_NET_BUFFER_LIST_INFO tsoInfo;
tsoInfo.Value = NET_BUFFER_LIST_INFO(curNbl,
TcpLargeSendNetBufferListInfo);
OVS_LOG_TRACE("MSS %u packet len %u", tsoInfo.LsoV1Transmit.MSS, packetLength);
if (tsoInfo.LsoV1Transmit.MSS) {
OVS_LOG_TRACE("l4Offset %d", layers->l4Offset);
*newNbl = OvsTcpSegmentNBL(switchContext, curNbl, layers,
tsoInfo.LsoV1Transmit.MSS, headRoom);
if (*newNbl == NULL) {
OVS_LOG_ERROR("Unable to segment NBL");
return NDIS_STATUS_FAILURE;
}
}
}
/* If we didn't split the packet above, make a copy now */
if (*newNbl == NULL) {
*newNbl = OvsPartialCopyNBL(switchContext, curNbl, 0, headRoom,
FALSE /*NBL info*/);
if (*newNbl == NULL) {
OVS_LOG_ERROR("Unable to copy NBL");
return NDIS_STATUS_FAILURE;
}
}
curNbl = *newNbl;
for (curNb = NET_BUFFER_LIST_FIRST_NB(curNbl); curNb != NULL;
curNb = curNb->Next) {
status = NdisRetreatNetBufferDataStart(curNb, headRoom, 0, NULL);
if (status != NDIS_STATUS_SUCCESS) {
goto ret_error;
}
curMdl = NET_BUFFER_CURRENT_MDL(curNb);
bufferStart = (PUINT8)MmGetSystemAddressForMdlSafe(curMdl, LowPagePriority);
if (!bufferStart) {
status = NDIS_STATUS_RESOURCES;
goto ret_error;
}
bufferStart += NET_BUFFER_CURRENT_MDL_OFFSET(curNb);
if (NET_BUFFER_NEXT_NB(curNb)) {
OVS_LOG_TRACE("nb length %u next %u", NET_BUFFER_DATA_LENGTH(curNb),
NET_BUFFER_DATA_LENGTH(curNb->Next));
}
/* L2 header */
ethHdr = (EthHdr *)bufferStart;
NdisMoveMemory(ethHdr->Destination, fwdInfo->dstMacAddr,
sizeof ethHdr->Destination + sizeof ethHdr->Source);
ASSERT(((PCHAR)&fwdInfo->dstMacAddr + sizeof fwdInfo->dstMacAddr) ==
(PCHAR)&fwdInfo->srcMacAddr);
ethHdr->Type = htons(ETH_TYPE_IPV4);
// XXX: question: there are fields in the OvsIPv4TunnelKey for ttl and such,
// should we use those values instead? or will they end up being
// uninitialized;
/* IP header */
ipHdr = (IPHdr *)((PCHAR)ethHdr + sizeof *ethHdr);
ipHdr->ihl = sizeof *ipHdr / 4;
ipHdr->version = IPV4;
ipHdr->tos = 0;
ipHdr->tot_len = htons(NET_BUFFER_DATA_LENGTH(curNb) - sizeof *ethHdr);
ipHdr->id = 0;
ipHdr->frag_off = IP_DF_NBO;
ipHdr->ttl = tunKey->ttl ? tunKey->ttl : VXLAN_DEFAULT_TTL;
ipHdr->protocol = IPPROTO_UDP;
ASSERT(tunKey->dst == fwdInfo->dstIpAddr);
ASSERT(tunKey->src == fwdInfo->srcIpAddr || tunKey->src == 0);
ipHdr->saddr = fwdInfo->srcIpAddr;
ipHdr->daddr = fwdInfo->dstIpAddr;
ipHdr->check = 0;
ipHdr->check = IPChecksum((UINT8 *)ipHdr, sizeof *ipHdr, 0);
/* UDP header */
udpHdr = (UDPHdr *)((PCHAR)ipHdr + sizeof *ipHdr);
udpHdr->source = htons(tunKey->flow_hash | 32768);
udpHdr->dest = VXLAN_UDP_PORT_NBO;
udpHdr->len = htons(NET_BUFFER_DATA_LENGTH(curNb) - headRoom +
sizeof *udpHdr + sizeof *vxlanHdr);
udpHdr->check = 0;
/* VXLAN header */
vxlanHdr = (VXLANHdr *)((PCHAR)udpHdr + sizeof *udpHdr);
vxlanHdr->flags1 = 0;
vxlanHdr->locallyReplicate = 0;
vxlanHdr->flags2 = 0;
vxlanHdr->reserved1 = 0;
if (tunKey->flags | OVS_TNL_F_KEY) {
vxlanHdr->vxlanID = VXLAN_TUNNELID_TO_VNI(tunKey->tunnelId);
vxlanHdr->instanceID = 1;
}
vxlanHdr->reserved2 = 0;
}
return STATUS_SUCCESS;
ret_error:
OvsCompleteNBL(switchContext, *newNbl, TRUE);
*newNbl = NULL;
return status;
}
