datapath-windows: Enable support for tracking ICMP code and type

Add support for tracking ICMP code and Type in the Hyper-V Conntrack
module. This code is similar to the userspace connection tracker.

Signed-off-by: Sairam Venugopal <vsairam@vmware.com>
Acked-by: Anand Kumar <kumaranand@vmware.com>
Signed-off-by: Gurucharan Shetty <guru@ovn.org>

1 files changed, 84 insertions, 0 deletions

diff --git a/datapath-windows/ovsext/Conntrack-icmp.c b/datapath-windows/ovsext/Conntrack-icmp.c
new file mode 100644
index 000000000..7db8e7d0e
--- /dev/null
+++ b/datapath-windows/ovsext/Conntrack-icmp.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2016 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.
+ */
+
+#include "NetProto.h"
+#include "Conntrack.h"
+#include <stddef.h>
+
+enum icmp_state {
+    ICMPS_FIRST,
+    ICMPS_REPLY,
+};
+
+struct conn_icmp {
+    struct OVS_CT_ENTRY up;
+    enum icmp_state state;
+};
+
+static const enum ct_timeout icmp_timeouts[] = {
+    [ICMPS_FIRST] = 60 * CT_INTERVAL_SEC,
+    [ICMPS_REPLY] = 30 * CT_INTERVAL_SEC,
+};
+
+static __inline struct conn_icmp *
+OvsCastConntrackEntryToIcmpEntry(OVS_CT_ENTRY* conn)
+{
+    return CONTAINER_OF(conn, struct conn_icmp, up);
+}
+
+enum CT_UPDATE_RES
+OvsConntrackUpdateIcmpEntry(OVS_CT_ENTRY* conn_,
+                            BOOLEAN reply,
+                            UINT64 now)
+{
+    struct conn_icmp *conn = OvsCastConntrackEntryToIcmpEntry(conn_);
+
+    if (reply && conn->state != ICMPS_REPLY) {
+        conn->state = ICMPS_REPLY;
+    }
+
+    OvsConntrackUpdateExpiration(&conn->up, now,
+                                 icmp_timeouts[conn->state]);
+
+    return CT_UPDATE_VALID;
+}
+
+BOOLEAN
+OvsConntrackValidateIcmpPacket(const ICMPHdr *icmp)
+{
+    return icmp->type == ICMP4_ECHO_REQUEST
+           || icmp->type == ICMP4_INFO_REQUEST
+           || icmp->type == ICMP4_TIMESTAMP_REQUEST;
+}
+
+OVS_CT_ENTRY *
+OvsConntrackCreateIcmpEntry(UINT64 now)
+{
+    struct conn_icmp *conn;
+
+    conn = OvsAllocateMemoryWithTag(sizeof(struct conn_icmp),
+                                    OVS_CT_POOL_TAG);
+    if (!conn) {
+        return NULL;
+    }
+
+    conn->state = ICMPS_FIRST;
+
+    OvsConntrackUpdateExpiration(&conn->up, now,
+                                 icmp_timeouts[conn->state]);
+
+    return &conn->up;
+}