- Fix problems with parsing sctpprim headers

- Add dissection of nbap (as encap or inside sctp primitive)

svn path=/trunk/; revision=19664

epan/dissectors/packet-catapult-dct2000.c

@@ -192,10 +192,11 @@ static gboolean find_sctpprim_variant1_data_offset(tvbuff_t *tvb, int *data_offs
     int offset = *data_offset;
 
     /* Get the sctpprim command code. */
-    guint8 tag = tvb_get_guint8(tvb, offset++);
+    guint8 first_tag = tvb_get_guint8(tvb, offset++);
+    guint8 tag;
 
     /* Only accept interested in data requests or indications */
-    switch (tag)
+    switch (first_tag)
     {
         case 0x04:  /* data request */
         case 0x62:  /* data indication */
@@ -204,17 +205,24 @@ static gboolean find_sctpprim_variant1_data_offset(tvbuff_t *tvb, int *data_offs
             return FALSE;
     }
 
-    /* Length field. msb set indicates 2 bytes */
-    if (tvb_get_guint8(tvb, offset) & 0x80)
+    if (first_tag == 0x04)
     {
-        offset += 2;
+        /* Overall length field. msb set indicates 2 bytes */
+        if (tvb_get_guint8(tvb, offset) & 0x80)
+        {
+            offset += 2;
+        }
+        else
+        {
+            offset++;
+        }
     }
     else
     {
-        offset++;
+        offset += 3;
     }
 
-    /* Skip any other TLC fields before reach payload */
+    /* Skip any other fields before reach payload */
     while (tvb_length_remaining(tvb, offset) > 2)
     {
         /* Look at next tag */
@@ -228,10 +236,29 @@ static gboolean find_sctpprim_variant1_data_offset(tvbuff_t *tvb, int *data_offs
         }
         else
         {
-            /* Read length in next byte */
-            length = tvb_get_guint8(tvb, offset++);
-            /* Skip the following value */
-            offset += length;
+            if (first_tag == 0x62)
+            {
+                switch (tag)
+                {
+                    case 0x0a: /* dest port */
+                    case 0x1e: /* strseqnum */
+                    case 0x0d:
+                        offset += 2;
+                        continue;
+                    case 0x1d:
+                    case 0x09:
+                    case 0x0c:
+                        offset += 4;
+                        continue;
+                }
+            }
+            else
+            {
+                /* Read length in next byte */
+                length = tvb_get_guint8(tvb, offset++);
+                /* Skip the following value */
+                offset += length;
+            }
         }
     }
 
@@ -282,6 +309,9 @@ static gboolean find_sctpprim_variant3_data_offset(tvbuff_t *tvb, int *data_offs
             /* 2-byte length field */
             offset += 2;
 
+            /* Skip 2-byte length field */
+            offset += 2;
+
             /* Data is here!!! */
             *data_offset = offset;
             return TRUE;
@@ -372,6 +402,16 @@ dissector_handle_t look_for_dissector(char *protocol_name)
     {
         return find_dissector("rtp");
     }
+    else
+    if (strcmp(protocol_name, "sipt") == 0)
+    {
+        return find_dissector("sip");
+    }
+    else
+    if (strncmp(protocol_name, "nbap_sctp", strlen("nbap_sctp")) == 0)
+    {
+        return find_dissector("nbap");
+    }
 
     /* Try for an exact match */
     else
@@ -696,6 +736,9 @@ dissect_catapult_dct2000(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
         case DCT2000_ENCAP_MTP2:
             protocol_handle = find_dissector("mtp2");
             break;
+        case DCT2000_ENCAP_NBAP:
+            protocol_handle = find_dissector("nbap");
+            break;
         case DCT2000_ENCAP_UNHANDLED:
             /* Show context.port in src or dest column as appropriate */
             if (check_col(pinfo->cinfo, COL_DEF_SRC) && direction == 0)

wiretap/catapult_dct2000.c

@@ -949,8 +949,17 @@ gboolean parse_line(gint line_length, gint *seconds, gint *useconds,
         *encap = DCT2000_ENCAP_MTP2;
     }
     else
+    if ((strcmp(protocol_name, "nbap") == 0) ||
+        (strcmp(protocol_name, "nbap_r4") == 0) ||
+        (strncmp(protocol_name, "nbap_sscfuni", strlen("nbap_sscfuni")) == 0))
     {
-        /* Not a supported board port protocol/encap, but can show as raw data anyway */
+        /* The entire message in these cases is nbap, so use an encap value. */
+        *encap = DCT2000_ENCAP_NBAP;
+    }
+    else
+    {
+        /* Not a supported board port protocol/encap, but can show as raw data or
+           in some cases find protocol embedded inside primitive */
         *encap = DCT2000_ENCAP_UNHANDLED;
     }
 

wiretap/catapult_dct2000.h

@@ -27,3 +27,4 @@ int catapult_dct2000_dump_can_write_encap(int encap);
 #define DCT2000_ENCAP_UNHANDLED 0
 #define DCT2000_ENCAP_SSCOP     101
 #define DCT2000_ENCAP_MTP2      102
+#define DCT2000_ENCAP_NBAP      103