datapath-windows: Added a new file to support Ipv4 fragments.

This patch adds functionalities to support IPv4 fragments, which will be
used by Conntrack module.

Added a new structure to hold the Ipv4 fragments and a hash table to
hold Ipv4 datagram entries. Also added a clean up thread that runs
every minute to delete the expired IPv4 datagram entries.

The individual fragments are ignored by the conntrack. Once all the
fragments are recieved, a new NBL is created out of the reassembled
fragments and conntrack executes actions on the new NBL.

Created new APIs OvsProcessIpv4Fragment() to process individual fragments,
OvsIpv4Reassemble() to reassemble Ipv4 fragments.

Signed-off-by: Anand Kumar <kumaranand@vmware.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Alin Gabriel Serdean <aserdean@cloudbasesolutions.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/datapath-windows/ovsext/IpFragment.h b/datapath-windows/ovsext/IpFragment.h
new file mode 100644
index 000000000..e650399e6
--- /dev/null
+++ b/datapath-windows/ovsext/IpFragment.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2017 VMware, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __IPFRAGMENT_H_
+#define __IPFRAGMENT_H_ 1
+#include "PacketIO.h"
+
+typedef struct _OVS_FRAGMENT_LIST {
+    CHAR *pbuff;
+    UINT16 len;
+    UINT16 offset;
+    struct _OVS_FRAGMENT_LIST *next;
+} OVS_FRAGMENT_LIST, *POVS_FRAGMENT_LIST;
+
+typedef struct _OVS_IPFRAG_KEY {
+    UINT8 protocol;
+    UINT8 pad_1[3];             /* Align the structure to address boundaries.*/
+    UINT16 id;
+    UINT16 pad_2;               /* Align the structure to address boundaries.*/
+    UINT32 sAddr;
+    UINT32 dAddr;
+    ovs_be64 tunnelId;
+} OVS_IPFRAG_KEY, *POVS_IPFRAG_KEY;
+
+typedef struct _OVS_IPFRAG_ENTRY {
+    NDIS_SPIN_LOCK lockObj;       /* To access the entry. */
+    UINT16 totalLen;
+    UINT16 recvdLen;
+    UINT16 mru;
+    UINT64 expiration;
+    OVS_IPFRAG_KEY fragKey;
+    POVS_FRAGMENT_LIST head;
+    POVS_FRAGMENT_LIST tail;
+    LIST_ENTRY link;
+} OVS_IPFRAG_ENTRY, *POVS_IPFRAG_ENTRY;
+
+typedef struct _OVS_IPFRAG_THREAD_CTX {
+    KEVENT event;
+    PVOID threadObject;
+    UINT32 exit;
+} OVS_IPFRAG_THREAD_CTX, *POVS_IPFRAG_THREAD_CTX;
+
+#define IP_FRAG_HASH_TABLE_SIZE ((UINT32)1 << 10)
+#define IP_FRAG_HASH_TABLE_MASK (IP_FRAG_HASH_TABLE_SIZE - 1)
+/*30s -Sufficient time to recieve all fragments.*/
+#define IPFRAG_ENTRY_TIMEOUT 300000000LL
+#define IPFRAG_CLEANUP_INTERVAL IPFRAG_ENTRY_TIMEOUT * 2 /*1m.*/
+PNET_BUFFER_LIST OvsIpv4FragmentNBL(PVOID ovsContext,
+                                    PNET_BUFFER_LIST nbl,
+                                    UINT16 mru);
+
+NDIS_STATUS OvsProcessIpv4Fragment(POVS_SWITCH_CONTEXT switchContext,
+                                   PNET_BUFFER_LIST *curNbl,
+                                   OvsCompletionList *completionList,
+                                   NDIS_SWITCH_PORT_ID sourcePort,
+                                   ovs_be64 tunnelId,
+                                   PNET_BUFFER_LIST *newNbl);
+NDIS_STATUS OvsInitIpFragment(POVS_SWITCH_CONTEXT context);
+VOID OvsCleanupIpFragment(VOID);
+#endif /* __IPFRAGMENT_H_ */