decode: return bool network layer

So that the caller can set the correct event type on error.

src/decode-vlan.c

@@ -87,8 +87,11 @@ int DecodeVLAN(ThreadVars *tv, DecodeThreadVars *dtv, Packet *p,
 
     p->vlan_id[p->vlan_idx++] = (uint16_t)GET_VLAN_ID(vlan_hdr);
 
-    DecodeNetworkLayer(tv, dtv, proto, p, pkt + VLAN_HEADER_LEN, len - VLAN_HEADER_LEN);
-
+    if (DecodeNetworkLayer(tv, dtv, proto, p,
+                pkt + VLAN_HEADER_LEN, len - VLAN_HEADER_LEN) == false) {
+        ENGINE_SET_INVALID_EVENT(p, VLAN_UNKNOWN_TYPE);
+        return TM_ECODE_FAILED;
+    }
     return TM_ECODE_OK;
 }
 

src/decode.h

@@ -1189,7 +1189,9 @@ static inline void DecodeLinkLayer(ThreadVars *tv, DecodeThreadVars *dtv,
     }
 }
 
-static inline void DecodeNetworkLayer(ThreadVars *tv, DecodeThreadVars *dtv,
+/** \brief decode network layer
+ *  \retval bool true if successful, false if unknown */
+static inline bool DecodeNetworkLayer(ThreadVars *tv, DecodeThreadVars *dtv,
         const uint16_t proto, Packet *p, const uint8_t *data, const uint32_t len)
 {
     switch (proto) {
@@ -1235,10 +1237,10 @@ static inline void DecodeNetworkLayer(ThreadVars *tv, DecodeThreadVars *dtv,
             }
             break;
         default:
-            SCLogDebug("unknown ether type: %" PRIx32 "", proto);
-            ENGINE_SET_INVALID_EVENT(p, VLAN_UNKNOWN_TYPE); // TODO
-            break;
+            SCLogDebug("unknown ether type: %" PRIx16 "", proto);
+            return false;
     }
+    return true;
 }
 
 #endif /* __DECODE_H__ */