sig: Add ipv6 and ipv4 to list of protocols

With this patch it is possible to do:
 alert ipv6 any any -> any any
or
 alert ip4 any any -> any any
to match on IPv4 or IPv6 packets.

src/detect-engine-iponly.c

@@ -1027,6 +1027,15 @@ void IPOnlyMatchPacket(ThreadVars *tv,
                 if (bitarray & 0x01) {
                     Signature *s = de_ctx->sig_array[u * 8 + i];
 
+                    if ((s->proto.flags & DETECT_PROTO_IPV4) && !PKT_IS_IPV4(p)) {
+                        SCLogDebug("ip version didn't match");
+                        continue;
+                    }
+                    if ((s->proto.flags & DETECT_PROTO_IPV6) && !PKT_IS_IPV6(p)) {
+                        SCLogDebug("ip version didn't match");
+                        continue;
+                    }
+
                     if (DetectProtoContainsProto(&s->proto, p->proto) == 0) {
                         SCLogDebug("proto didn't match");
                         continue;

src/detect-engine-proto.c

@@ -115,6 +115,16 @@ int DetectProtoParse(DetectProto *dp, char *str)
         proto = IPPROTO_SCTP;
         dp->proto[proto / 8] |= 1 << (proto % 8);
         SCLogDebug("SCTP protocol detected");
+    } else if (strcasecmp(str,"ipv4") == 0 ||
+               strcasecmp(str,"ip4") == 0 ) {
+        dp->flags |= DETECT_PROTO_IPV4;
+        memset(dp->proto, 0xff, sizeof(dp->proto));
+        SCLogDebug("IPv4 protocol detected");
+    } else if (strcasecmp(str,"ipv6") == 0 ||
+               strcasecmp(str,"ip6") == 0 ) {
+        dp->flags |= DETECT_PROTO_IPV6;
+        memset(dp->proto, 0xff, sizeof(dp->proto));
+        SCLogDebug("IPv6 protocol detected");
     } else if (strcasecmp(str,"ip") == 0 ||
                strcasecmp(str,"pkthdr") == 0) {
         /* Proto "ip" is treated as an "any" */

src/detect-engine-proto.h

@@ -24,12 +24,14 @@
 #ifndef __DETECT_PROTO_H__
 #define __DETECT_PROTO_H__
 
-#define DETECT_PROTO_ANY            0x01 /**< Indicate that given protocol
+#define DETECT_PROTO_ANY            (1 << 0) /**< Indicate that given protocol
                                               is considered as IP */
-#define DETECT_PROTO_ONLY_PKT       0x02 /**< Indicate that we only care
+#define DETECT_PROTO_ONLY_PKT       (1 << 1) /**< Indicate that we only care
                                               about packet payloads. */
-#define DETECT_PROTO_ONLY_STREAM    0x04 /**< Indicate that we only care
+#define DETECT_PROTO_ONLY_STREAM    (1 << 2) /**< Indicate that we only care
                                               about stream payloads. */
+#define DETECT_PROTO_IPV4           (1 << 3) /**< IPv4 only */
+#define DETECT_PROTO_IPV6           (1 << 4) /**< IPv6 only */
 
 typedef struct DetectProto_ {
     uint8_t proto[256/8]; /**< bit array for 256 protocol bits */

src/detect-ipproto.c

@@ -226,8 +226,12 @@ static int DetectIPProtoSetup(DetectEngineCtx *de_ctx, Signature *s, char *optst
         goto error;
     }
 
-    /* reset our "any" (or "ip") state */
-    if (s->proto.flags & DETECT_PROTO_ANY) {
+    /* Reset our "any" (or "ip") state: for ipv4, ipv6 and ip cases, the bitfield
+     * s->proto.proto have all bit set to 1 to be able to match any protocols. ipproto
+     * will refined the protocol list and thus it needs to reset the bitfield to zero
+     * before setting the value specified by the ip_proto keyword.
+     */
+    if (s->proto.flags & (DETECT_PROTO_ANY | DETECT_PROTO_IPV6 | DETECT_PROTO_IPV4)) {
         s->proto.flags &= ~DETECT_PROTO_ANY;
         memset(s->proto.proto, 0x00, sizeof(s->proto.proto));
     }

src/detect.c

@@ -1641,6 +1641,15 @@ int SigMatchSignatures(ThreadVars *th_v, DetectEngineCtx *de_ctx, DetectEngineTh
             }
         }
 
+        if ((s->proto.flags & DETECT_PROTO_IPV4) && !PKT_IS_IPV4(p)) {
+            SCLogDebug("ip version didn't match");
+            goto next;
+        }
+        if ((s->proto.flags & DETECT_PROTO_IPV6) && !PKT_IS_IPV6(p)) {
+            SCLogDebug("ip version didn't match");
+            goto next;
+        }
+
         if (DetectProtoContainsProto(&s->proto, IP_GET_IPPROTO(p)) == 0) {
             SCLogDebug("proto didn't match");
             goto next;