packet: gre over ip link type

src/decode.h

@@ -1077,6 +1077,7 @@ void DecodeGlobalConfig(void);
  * Libpcap on at least OpenBSD returns 101 as datalink type for RAW pcaps though. */
 #define LINKTYPE_RAW2        101
 #define LINKTYPE_IPV4        228
+#define LINKTYPE_GRE_OVER_IP 778
 #define PPP_OVER_GRE         11
 #define VLAN_OVER_GRE        13
 

src/source-af-packet.c

@@ -2729,6 +2729,7 @@ TmEcode DecodeAFP(ThreadVars *tv, Packet *p, void *data, PacketQueue *pq, Packet
             DecodePPP(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p), pq);
             break;
         case LINKTYPE_RAW:
+        case LINKTYPE_GRE_OVER_IP:
             DecodeRaw(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p), pq);
             break;
         case LINKTYPE_NULL:

src/source-pcap-file-helper.c

@@ -212,6 +212,7 @@ TmEcode ValidateLinkType(int datalink, Decoder *decoder)
         case LINKTYPE_IPV4:
         case LINKTYPE_RAW:
         case LINKTYPE_RAW2:
+        case LINKTYPE_GRE_OVER_IP:
             *decoder = DecodeRaw;
             break;
         case LINKTYPE_NULL:

src/source-pcap.c

@@ -563,6 +563,7 @@ TmEcode DecodePcap(ThreadVars *tv, Packet *p, void *data, PacketQueue *pq, Packe
             DecodePPP(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p), pq);
             break;
         case LINKTYPE_RAW:
+        case LINKTYPE_GRE_OVER_IP:
             DecodeRaw(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p), pq);
             break;
         case LINKTYPE_NULL: