diff mbox

[ovs-dev,v2,4/5] datapath-windows: Updated OvsTcpSegmentNBL to handle IP fragments.

Message ID 20170112211346.612-5-kumaranand@vmware.com
State Changes Requested
Headers show

Commit Message

Anand Kumar Jan. 12, 2017, 9:13 p.m. UTC
With this patch, OvsTcpSegmentNBL not only supports tcp segments but also the
IP fragments.

To reflect the new changes, renamed function name from OvsTcpSegmentNBL
to OvsFragmentNBL and created a wrapper for OvsTcpSegmentNBL.
---
 datapath-windows/ovsext/BufferMgmt.c | 189 +++++++++++++++++++++++++----------
 datapath-windows/ovsext/BufferMgmt.h |  10 +-
 datapath-windows/ovsext/Geneve.c     |   2 +-
 datapath-windows/ovsext/Gre.c        |   2 +-
 datapath-windows/ovsext/Stt.c        |   2 +-
 datapath-windows/ovsext/User.c       |   2 +-
 datapath-windows/ovsext/Vxlan.c      |   2 +-
 7 files changed, 150 insertions(+), 59 deletions(-)
diff mbox

Patch

diff --git a/datapath-windows/ovsext/BufferMgmt.c b/datapath-windows/ovsext/BufferMgmt.c
index 6027c35..3f7c0cd 100644
--- a/datapath-windows/ovsext/BufferMgmt.c
+++ b/datapath-windows/ovsext/BufferMgmt.c
@@ -1083,6 +1083,31 @@  nblcopy_error:
     return NULL;
 }
 
+NDIS_STATUS
+GetIpHeaderInfo(PNET_BUFFER_LIST curNbl,
+                UINT32 *hdrSize)
+{
+    CHAR *ethBuf[sizeof(EthHdr)];
+    EthHdr *eth;
+    IPHdr *ipHdr;
+    PNET_BUFFER curNb;
+
+    curNb = NET_BUFFER_LIST_FIRST_NB(curNbl);
+    ASSERT(NET_BUFFER_NEXT_NB(curNb) == NULL);
+
+    eth = (EthHdr *)NdisGetDataBuffer(curNb, ETH_HEADER_LENGTH,
+                                      (PVOID)&ethBuf, 1, 0);
+    if (eth == NULL) {
+        return NDIS_STATUS_INVALID_PACKET;
+    }
+    ipHdr = (IPHdr *)((PCHAR)eth + ETH_HEADER_LENGTH);
+    if (ipHdr == NULL) {
+        return NDIS_STATUS_INVALID_PACKET;
+    }
+    *hdrSize = (UINT32)(ETH_HEADER_LENGTH + (ipHdr->ihl * 4));
+    return NDIS_STATUS_SUCCESS;
+}
+
 /*
  * --------------------------------------------------------------------------
  * GetSegmentHeaderInfo
@@ -1112,15 +1137,16 @@  GetSegmentHeaderInfo(PNET_BUFFER_LIST nbl,
 
 /*
  * --------------------------------------------------------------------------
- * FixSegmentHeader
+ * FixPacketHeader
  *
- *    Fix IP length, IP checksum, TCP sequence number and TCP checksum
- *    in the segment.
+ *    Fix IP length, Offset, IP checksum, TCP sequence number and TCP checksum
+ *    in the segment as applicable.
  * --------------------------------------------------------------------------
  */
 static NDIS_STATUS
-FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber,
-                 BOOLEAN lastPacket, UINT16 packetCounter)
+FixPacketHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber,
+                BOOLEAN lastPacket, UINT16 packetCounter, UINT16 offset,
+                BOOLEAN isFragment)
 {
     EthHdr *dstEth = NULL;
     TCPHdr *dstTCP = NULL;
@@ -1139,41 +1165,55 @@  FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber,
     case ETH_TYPE_IPV4_NBO:
     {
         IPHdr *dstIP = NULL;
-
-        ASSERT((INT)MmGetMdlByteCount(mdl) - NET_BUFFER_CURRENT_MDL_OFFSET(nb)
+        if (!isFragment) {
+            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)
+            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;
+            /* 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;
+            dstTCP->seq = htonl(seqNumber);
+
+            /*
+             * Set the TCP FIN and PSH bit only for the last packet
+             * More information can be found under:
+             * https://msdn.microsoft.com/en-us/library/windows/hardware/ff568840%28v=vs.85%29.aspx
+             */
+            if (dstTCP->fin) {
+                dstTCP->fin = lastPacket;
+            }
+            if (dstTCP->psh) {
+                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);
+        } else {
+            ASSERT((INT)MmGetMdlByteCount(mdl) - NET_BUFFER_CURRENT_MDL_OFFSET(nb)
+                >= sizeof(EthHdr) + sizeof(IPHdr));
+
+            dstIP = (IPHdr *)((PCHAR)dstEth + sizeof(*dstEth));
+            ASSERT((INT)MmGetMdlByteCount(mdl) - NET_BUFFER_CURRENT_MDL_OFFSET(nb)
+                >= sizeof(EthHdr) + dstIP->ihl * 4);
+            dstIP->tot_len = htons(segmentSize + dstIP->ihl * 4);
+            if (lastPacket) {
+                dstIP->frag_off = htons(offset & IP_OFFSET);
+            } else {
+                dstIP->frag_off = htons((offset & IP_OFFSET) | IP_MF);
+            }
+        }
         dstIP->check = 0;
         dstIP->check = IPChecksum((UINT8 *)dstIP, dstIP->ihl * 4, 0);
-        dstTCP->seq = htonl(seqNumber);
-
-        /*
-         * Set the TCP FIN and PSH bit only for the last packet
-         * More information can be found under:
-         * https://msdn.microsoft.com/en-us/library/windows/hardware/ff568840%28v=vs.85%29.aspx
-         */
-        if (dstTCP->fin) {
-            dstTCP->fin = lastPacket;
-        }
-        if (dstTCP->psh) {
-            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);
         break;
     }
     case ETH_TYPE_IPV6_NBO:
@@ -1217,9 +1257,27 @@  FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber,
     return STATUS_SUCCESS;
 }
 
+ /*
+  * --------------------------------------------------------------------------
+ * OvsTcpSegmentNBL --
+ *      Wrapper function to Fragment a given NBL based on MSS
+ * --------------------------------------------------------------------------
+ */
+PNET_BUFFER_LIST
+OvsTcpSegmentNBL(PVOID ovsContext,
+                 PNET_BUFFER_LIST nbl,
+                 POVS_PACKET_HDR_INFO hdrInfo,
+                 UINT32 mss,
+                 UINT32 headRoom,
+                 BOOLEAN isIpFragment)
+{
+    return OvsFragmentNBL(ovsContext, nbl, hdrInfo, mss, headRoom, isIpFragment);
+}
+
+
 /*
  * --------------------------------------------------------------------------
- * OvsTcpSegmentNBL --
+ * OvsFragmentNBL --
  *
  *    Segment TCP payload, and prepend each segment with ether/IP/TCP header.
  *    Leave headRoom for additional encap.
@@ -1234,24 +1292,25 @@  FixSegmentHeader(PNET_BUFFER nb, UINT16 segmentSize, UINT32 seqNumber,
  * --------------------------------------------------------------------------
  */
 PNET_BUFFER_LIST
-OvsTcpSegmentNBL(PVOID ovsContext,
-                 PNET_BUFFER_LIST nbl,
-                 POVS_PACKET_HDR_INFO hdrInfo,
-                 UINT32 mss,
-                 UINT32 headRoom)
+OvsFragmentNBL(PVOID ovsContext,
+               PNET_BUFFER_LIST nbl,
+               POVS_PACKET_HDR_INFO hdrInfo,
+               UINT32 mss,
+               UINT32 headRoom,
+               BOOLEAN isIpFragment)
 {
     POVS_SWITCH_CONTEXT context = (POVS_SWITCH_CONTEXT)ovsContext;
 #ifdef DBG
     POVS_NBL_POOL ovsPool = &context->ovsPool;
 #endif
     POVS_BUFFER_CONTEXT dstCtx, srcCtx;
-    UINT32 size, hdrSize, seqNumber;
+    UINT32 size, hdrSize, nblSize, seqNumber = 0;
     PNET_BUFFER_LIST newNbl;
     PNET_BUFFER nb, newNb;
     NDIS_STATUS status;
     UINT16 segmentSize;
     ULONG copiedSize;
-    UINT16 packetCounter = 0;
+    UINT16 offset = 0, packetCounter = 0;
 
     srcCtx = (POVS_BUFFER_CONTEXT)NET_BUFFER_LIST_CONTEXT_DATA_START(nbl);
     if (srcCtx == NULL || srcCtx->magic != OVS_CTX_MAGIC) {
@@ -1263,18 +1322,28 @@  OvsTcpSegmentNBL(PVOID ovsContext,
     nb = NET_BUFFER_LIST_FIRST_NB(nbl);
     ASSERT(NET_BUFFER_NEXT_NB(nb) == NULL);
 
-    /* Figure out the segment header size */
-    status = GetSegmentHeaderInfo(nbl, hdrInfo, &hdrSize, &seqNumber);
+    /* Figure out the header size */
+    if (isIpFragment) {
+        status = GetIpHeaderInfo(nbl, &hdrSize);
+    } else {
+        status = GetSegmentHeaderInfo(nbl, hdrInfo, &hdrSize, &seqNumber);
+    }
     if (status != NDIS_STATUS_SUCCESS) {
         OVS_LOG_INFO("Cannot parse NBL header");
         return NULL;
     }
-
+    /* Get the NBL size. */
+    if (isIpFragment) {
+        nblSize = mss - hdrSize;
+    } else {
+        nblSize = mss;
+    }
     size = NET_BUFFER_DATA_LENGTH(nb) - hdrSize;
 
     /* XXX add to ovsPool counters? */
-    newNbl = NdisAllocateFragmentNetBufferList(nbl, NULL,
-            NULL, hdrSize, mss, hdrSize + headRoom , 0, 0);
+    newNbl = NdisAllocateFragmentNetBufferList(nbl, NULL, NULL, hdrSize,
+                                               nblSize, hdrSize + headRoom ,
+                                               0, 0);
     if (newNbl == NULL) {
         return NULL;
     }
@@ -1282,7 +1351,7 @@  OvsTcpSegmentNBL(PVOID ovsContext,
     /* Now deal with TCP payload */
     for (newNb = NET_BUFFER_LIST_FIRST_NB(newNbl); newNb != NULL;
             newNb = NET_BUFFER_NEXT_NB(newNb)) {
-        segmentSize = (size > mss ? mss : size) & 0xffff;
+        segmentSize = (size > nblSize ? nblSize : size) & 0xffff;
         if (headRoom) {
             NdisAdvanceNetBufferDataStart(newNb, headRoom, FALSE, NULL);
         }
@@ -1294,17 +1363,22 @@  OvsTcpSegmentNBL(PVOID ovsContext,
             goto nblcopy_error;
         }
 
-        status = FixSegmentHeader(newNb, segmentSize, seqNumber,
-                                  NET_BUFFER_NEXT_NB(newNb) == NULL,
-                                  packetCounter);
+        status = FixPacketHeader(newNb, segmentSize, seqNumber,
+                                 NET_BUFFER_NEXT_NB(newNb) == NULL,
+                                 packetCounter, offset, isIpFragment);
+
         if (status != NDIS_STATUS_SUCCESS) {
             goto nblcopy_error;
         }
 
 
         /* Move on to the next segment */
+        if (isIpFragment) {
+            offset += (segmentSize) / 8;
+        } else {
+            seqNumber += segmentSize;
+        }
         size -= segmentSize;
-        seqNumber += segmentSize;
         packetCounter++;
     }
 
@@ -1318,6 +1392,15 @@  OvsTcpSegmentNBL(PVOID ovsContext,
         goto nbl_context_error;
     }
 
+    if (isIpFragment) {
+        /* Copy with Flag - NDIS_SWITCH_COPY_NBL_INFO_FLAGS_PRESERVE_DESTINATIONS. */
+        status = context->NdisSwitchHandlers.
+            CopyNetBufferListInfo(context->ovsPool.ndisContext, newNbl, nbl, 1);
+
+        if (status != NDIS_STATUS_SUCCESS) {
+            goto nbl_context_error;
+        }
+    }
     newNbl->ParentNetBufferList = nbl;
 
     /* Remember it's a fragment NBL so we can free it properly */
diff --git a/datapath-windows/ovsext/BufferMgmt.h b/datapath-windows/ovsext/BufferMgmt.h
index 11a05b2..110f4c4 100644
--- a/datapath-windows/ovsext/BufferMgmt.h
+++ b/datapath-windows/ovsext/BufferMgmt.h
@@ -115,7 +115,15 @@  PNET_BUFFER_LIST OvsTcpSegmentNBL(PVOID context,
                                   PNET_BUFFER_LIST nbl,
                                   POVS_PACKET_HDR_INFO hdrInfo,
                                   UINT32 MSS,
-                                  UINT32 headRoom);
+                                  UINT32 headRoom,
+                                  BOOLEAN isIpFragment);
+
+PNET_BUFFER_LIST OvsFragmentNBL(PVOID context,
+                                PNET_BUFFER_LIST nbl,
+                                POVS_PACKET_HDR_INFO hdrInfo,
+                                UINT32 MSS,
+                                UINT32 headRoom,
+                                BOOLEAN isIpFragment);
 
 PNET_BUFFER_LIST OvsAllocateNBLFromBuffer(PVOID context,
                                           PVOID buffer,
diff --git a/datapath-windows/ovsext/Geneve.c b/datapath-windows/ovsext/Geneve.c
index d38a656..2f0153f 100644
--- a/datapath-windows/ovsext/Geneve.c
+++ b/datapath-windows/ovsext/Geneve.c
@@ -118,7 +118,7 @@  NDIS_STATUS OvsEncapGeneve(POVS_VPORT_ENTRY vport,
         if (mss) {
             OVS_LOG_TRACE("l4Offset %d", layers->l4Offset);
             *newNbl = OvsTcpSegmentNBL(switchContext, curNbl, layers,
-                                       mss, headRoom);
+                                       mss, headRoom, FALSE);
             if (*newNbl == NULL) {
                 OVS_LOG_ERROR("Unable to segment NBL");
                 return NDIS_STATUS_FAILURE;
diff --git a/datapath-windows/ovsext/Gre.c b/datapath-windows/ovsext/Gre.c
index c5da064..f095742 100644
--- a/datapath-windows/ovsext/Gre.c
+++ b/datapath-windows/ovsext/Gre.c
@@ -158,7 +158,7 @@  OvsDoEncapGre(POVS_VPORT_ENTRY vport,
         if (mss) {
             OVS_LOG_TRACE("l4Offset %d", layers->l4Offset);
             *newNbl = OvsTcpSegmentNBL(switchContext, curNbl, layers,
-                                       mss, headRoom);
+                                       mss, headRoom, FALSE);
             if (*newNbl == NULL) {
                 OVS_LOG_ERROR("Unable to segment NBL");
                 return NDIS_STATUS_FAILURE;
diff --git a/datapath-windows/ovsext/Stt.c b/datapath-windows/ovsext/Stt.c
index 9da81dc..e7da6f4 100644
--- a/datapath-windows/ovsext/Stt.c
+++ b/datapath-windows/ovsext/Stt.c
@@ -185,7 +185,7 @@  OvsDoEncapStt(POVS_VPORT_ENTRY vport,
         if ((innerFrameLen > OVS_MAX_STT_PACKET_LENGTH) ||
             (layers->l4Offset > OVS_MAX_STT_L4_OFFSET_LENGTH)) {
             *newNbl = OvsTcpSegmentNBL(switchContext, curNbl, layers,
-                mss - headRoom, headRoom);
+                                       mss - headRoom, headRoom, FALSE);
             if (*newNbl == NULL) {
                 OVS_LOG_ERROR("Unable to segment NBL");
                 return NDIS_STATUS_FAILURE;
diff --git a/datapath-windows/ovsext/User.c b/datapath-windows/ovsext/User.c
index 290a87d..7cf88c8 100644
--- a/datapath-windows/ovsext/User.c
+++ b/datapath-windows/ovsext/User.c
@@ -784,7 +784,7 @@  OvsCreateAndAddPackets(PVOID userData,
         if (tsoInfo.LsoV1Transmit.MSS) {
             OVS_LOG_TRACE("l4Offset %d", hdrInfo->l4Offset);
             newNbl = OvsTcpSegmentNBL(switchContext, nbl, hdrInfo,
-                    tsoInfo.LsoV1Transmit.MSS , 0);
+                                      tsoInfo.LsoV1Transmit.MSS , 0, FALSE);
             if (newNbl == NULL) {
                 return NDIS_STATUS_FAILURE;
             }
diff --git a/datapath-windows/ovsext/Vxlan.c b/datapath-windows/ovsext/Vxlan.c
index 949e069..eaab8bb 100644
--- a/datapath-windows/ovsext/Vxlan.c
+++ b/datapath-windows/ovsext/Vxlan.c
@@ -205,7 +205,7 @@  OvsDoEncapVxlan(POVS_VPORT_ENTRY vport,
         if (mss) {
             OVS_LOG_TRACE("l4Offset %d", layers->l4Offset);
             *newNbl = OvsTcpSegmentNBL(switchContext, curNbl, layers,
-                                       mss, headRoom);
+                                       mss, headRoom, FALSE);
             if (*newNbl == NULL) {
                 OVS_LOG_ERROR("Unable to segment NBL");
                 return NDIS_STATUS_FAILURE;