From Gavin Heer:

 Here's a patch that decodes MMS(Manufacturing Messaging
Specification) when transported over COTP/TPKT/TCP.  Previously, MMS would only be decoded if the OSI Presentation Layers were present. Now MMS/COTP/TPKT/TCP is dissected.
With a change to use more functions from packet-ber

svn path=/trunk/; revision=21608

2 files changed, 52 insertions, 2 deletions

diff --git a/asn1/mms/mms.asn b/asn1/mms/mms.asn
index bc11a5f8ae..d7d9a7b895 100644
--- a/asn1/mms/mms.asn
+++ b/asn1/mms/mms.asn
@@ -21,7 +21,7 @@ IMPORTS
 	AP-title,
 	AP-invocation-identifier,
 	AE-qualifier,
-        AE-invocation-identifier
+    AE-invocation-identifier
 FROM ISO-8650-ACSE-1;
 
 
diff --git a/asn1/mms/packet-mms-template.c b/asn1/mms/packet-mms-template.c
index b3567c3e1b..776d7b8a8e 100644
--- a/asn1/mms/packet-mms-template.c
+++ b/asn1/mms/packet-mms-template.c
@@ -110,9 +110,59 @@ void proto_register_mms(void) {
 }
 
 
+static gboolean
+dissect_mms_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree)
+{	
+	/* must check that this really is an mms packet */
+	int offset = 0;
+	guint32 length = 0 ;
+	guint32 oct;
+	gint idx = 0 ;
+
+	gint8 tmp_class;
+	gboolean tmp_pc;
+	gint32 tmp_tag;
+	
+		/* first, check do we have at least 2 bytes (pdu) */
+	if (!tvb_bytes_exist(tvb, 0, 2))
+		return FALSE;	/* no */
+	
+	/* can we recognize MMS PDU ? Return FALSE if  not */
+	/*   get MMS PDU type */
+	offset = get_ber_identifier(tvb, offset, &tmp_class, &tmp_pc, &tmp_tag);
+	
+	/* check MMS type */
+	
+	/* Class should be constructed */ 
+	if (tmp_class!=BER_CLASS_CON)
+		return FALSE;
+	
+	/* see if the tag is a valid MMS PDU */
+	match_strval_idx(tmp_tag, mms_MMSpdu_vals, &idx);
+	if  (idx == -1) { 
+	 	return FALSE;  /* no, it isn't an MMS PDU */
+	}
+	
+	/* check MMS length  */
+	oct = tvb_get_guint8(tvb, offset)& 0x7F;
+	if (oct==0)
+		/* MMS requires length after tag so not MMS if indefinite length*/
+		return FALSE;
+						
+	offset = get_ber_length(NULL, tvb, offset, &length, NULL);
+	/* do we have enough bytes? */
+	if (!tvb_bytes_exist(tvb, offset, length))
+		return FALSE; 
+		
+	dissect_mms(tvb, pinfo, parent_tree);
+	return TRUE;	
+}
+
 /*--- proto_reg_handoff_mms --- */
 void proto_reg_handoff_mms(void) {
 	register_ber_oid_dissector("1.0.9506.2.3", dissect_mms, proto_mms,"MMS");
 	register_ber_oid_dissector("1.0.9506.2.1", dissect_mms, proto_mms,"mms-abstract-syntax-version1(1)");
-
+	heur_dissector_add("cotp", dissect_mms_heur, proto_mms);
+	heur_dissector_add("cotp_is", dissect_mms_heur, proto_mms);
 }
+