path: root/plugins/megaco/packet-megaco.c

/* packet-megaco.c
* Routines for megaco packet disassembly
* RFC 3015
*
* $Id$
*
* Christian Falckenberg, 2002/10/17
* Copyright (c) 2002 by Christian Falckenberg
*                       <christian.falckenberg@nortelnetworks.com>
*
* Christoph Wiest,		2003/06/28
* Modified 2003 by		Christoph Wiest
*						<ch.wiest@tesionmail.de>
* Modifyed 2004 by		Anders Broman
*						<anders.broman@ericsson.com>
* To handle TPKT headers if over TCP
* Modified 2005 by		Karl Knoebl
*						<karl.knoebl@siemens.com>
*	provide info to COL_INFO and some "prettification"
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@ethereal.com>
* Copyright 1999 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/


#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "moduleinfo.h"

#include <stdio.h>
#include <stdlib.h>
#include <gmodule.h>
#include <ctype.h>
#include <time.h>
#include <string.h>
#include <epan/packet.h>
#include <epan/addr_resolv.h>
#include <epan/prefs.h>
#include <epan/strutil.h>
#include <epan/sctpppids.h>
#include <epan/dissectors/packet-tpkt.h>

#ifndef ENABLE_STATIC
G_MODULE_EXPORT const gchar version[] = VERSION;
#endif

#define PORT_MEGACO_TXT 2944
#define PORT_MEGACO_BIN 2945


void proto_reg_handoff_megaco(void);

/* Define the megaco proto */
static int proto_megaco			= -1;

/* Define headers for megaco */
static int hf_megaco_version    	= -1;
static int hf_megaco_transaction   	= -1;
static int hf_megaco_transid    	= -1;
static int hf_megaco_Context		= -1;
static int hf_megaco_command_line	= -1;
static int hf_megaco_command		= -1;
static int hf_megaco_termid			= -1;



/* Define headers in subtree for megaco */
static int hf_megaco_modem_descriptor           = -1;
static int hf_megaco_multiplex_descriptor       = -1;
static int hf_megaco_media_descriptor			= -1;
static int hf_megaco_events_descriptor          = -1;
static int hf_megaco_signal_descriptor          = -1;
static int hf_megaco_audit_descriptor           = -1;
static int hf_megaco_servicechange_descriptor	= -1;
static int hf_megaco_digitmap_descriptor		= -1;
static int hf_megaco_statistics_descriptor		= -1;
static int hf_megaco_observedevents_descriptor	= -1;
static int hf_megaco_topology_descriptor		= -1;
static int hf_megaco_error_descriptor			= -1;
static int hf_megaco_TerminationState_descriptor= -1;
static int hf_megaco_Remote_descriptor 			= -1;
static int hf_megaco_Local_descriptor 			= -1;
static int hf_megaco_LocalControl_descriptor 	= -1;
static int hf_megaco_packages_descriptor		= -1;
static int hf_megaco_error_Frame				= -1;
static int hf_megaco_Service_State				= -1;
static int hf_megaco_Event_Buffer_Control		= -1;
static int hf_megaco_mode						= -1;
static int hf_megaco_reserve_group				= -1;
static int hf_megaco_reserve_value				= -1;
static int hf_megaco_streamid 					= -1;
static int hf_megaco_requestid 					= -1;
static int hf_megaco_pkgdname					= -1;
static int hf_megaco_mId						= -1;
static int hf_megaco_h245						= -1;

/* Define the trees for megaco */
static int ett_megaco 							= -1;
static int ett_megaco_command_line 				= -1;
static int ett_megaco_mediadescriptor			= -1;
static int ett_megaco_descriptors 				= -1;
static int ett_megaco_TerminationState			= -1;
static int ett_megaco_Localdescriptor			= -1;
static int ett_megaco_Remotedescriptor			= -1;
static int ett_megaco_LocalControldescriptor	= -1;
static int ett_megaco_auditdescriptor			= -1;
static int ett_megaco_eventsdescriptor			= -1;
static int ett_megaco_observedeventsdescriptor	= -1;
static int ett_megaco_observedevent				= -1;
static int ett_megaco_packagesdescriptor		= -1;
static int ett_megaco_requestedevent			= -1;
static int ett_megaco_signalsdescriptor			= -1;
static int ett_megaco_requestedsignal			= -1;
static int ett_megaco_h245 						= -1;

static dissector_handle_t megaco_text_handle;


/*
* Here are the global variables associated with
* the various user definable characteristics of the dissection
*
* MEGACO has two kinds of message formats: text and binary
*
* global_megaco_raw_text determines whether we are going to display
* the raw text of the megaco message, much like the HTTP dissector does.
*
* global_megaco_dissect_tree determines whether we are going to display
* a detailed tree that expresses a somewhat more semantically meaningful
* decode.
*/
static int global_megaco_txt_tcp_port = PORT_MEGACO_TXT;
static int global_megaco_txt_udp_port = PORT_MEGACO_TXT;
#if 0
static int global_megaco_bin_tcp_port = PORT_MEGACO_BIN;
static int global_megaco_bin_udp_port = PORT_MEGACO_BIN;
#endif
static gboolean global_megaco_raw_text = TRUE;
static gboolean global_megaco_dissect_tree = TRUE;

/*
* Variables to allow for proper deletion of dissector registration when
* the user changes port from the gui.
*/
static int txt_tcp_port = 0;
static int txt_udp_port = 0;
#if 0
static int bin_tcp_port = 0;
static int bin_udp_port = 0;
#endif

/* Some basic utility functions that are specific to this dissector */
static gint tvb_skip_wsp(tvbuff_t* tvb, gint offset);
static gint tvb_skip_wsp_return(tvbuff_t* tvb, gint offset);
/*
* The various functions that either dissect some
* subpart of MEGACO.  These aren't really proto dissectors but they
* are written in the same style.
*
*/
static void
dissect_megaco_descriptors(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, gint tvb_descriptors_start_offset, gint tvb_descriptors_end_offset);
static void
dissect_megaco_modemdescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_multiplexdescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_mediadescriptor(tvbuff_t *tvb, proto_tree *tree,packet_info *pinfo, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_eventsdescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_signaldescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_auditdescriptor(tvbuff_t *tvb, proto_tree *tree,packet_info *pinfo, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_servicechangedescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_digitmapdescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_statisticsdescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_observedeventsdescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_topologydescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_errordescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_RBRKT, gint tvb_previous_offset);
static void
dissect_megaco_TerminationStatedescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_next_offset, gint tvb_current_offset);
static void
dissect_megaco_Localdescriptor(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, gint tvb_next_offset, gint tvb_current_offset);
static void
dissect_megaco_Remotedescriptor(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, gint tvb_next_offset, gint tvb_current_offset);
static void
dissect_megaco_LocalControldescriptor(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo, gint tvb_next_offset, gint tvb_current_offset);
static void
dissect_megaco_Packagesdescriptor(tvbuff_t *tvb, proto_tree *tree, gint tvb_next_offset, gint tvb_current_offset);
static void
tvb_raw_text_add(tvbuff_t *tvb, proto_tree *tree);
static void
dissect_megaco_text(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);

static dissector_handle_t sdp_handle;
static dissector_handle_t h245_handle;
static proto_tree *top_tree;
/*
 * dissect_megaco_text over TCP, there will be a TPKT header there
 *
 */
static void dissect_megaco_text_tcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	int lv_tpkt_len;

	/* This code is copied from the Q.931 dissector, some parts skipped.
	 * Check whether this looks like a TPKT-encapsulated
	 * MEGACO packet.
	 *
	 * The minimum length of a MEGACO message is 6?:
	 * Re-assembly ?
	 */
	lv_tpkt_len = is_tpkt(tvb, 6);
	if (lv_tpkt_len == -1) {
		/*
		 * It's not a TPKT packet;
		 * Is in MEGACO ?
		 */
		dissect_megaco_text(tvb, pinfo, tree);
	}
	dissect_tpkt_encap(tvb, pinfo, tree, TRUE,
	    megaco_text_handle);
}
/*
 * dissect_megaco_text - The dissector for the MEGACO Protocol, using
 * text encoding.
 */
static void
dissect_megaco_text(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	gint		tvb_len, len;
	gint		tvb_offset,tvb_current_offset,tvb_previous_offset,tvb_next_offset,tokenlen;
	gint		tvb_command_start_offset, tvb_command_end_offset;
	gint		tvb_descriptors_start_offset, tvb_descriptors_end_offset;
	proto_tree  *megaco_tree, *megaco_tree_command_line, *ti, *sub_ti;
	proto_item* (*my_proto_tree_add_string)(proto_tree*, int, tvbuff_t*, gint, gint, const char*);

	guint8		word[7];
	guint8		transaction[30];
	guint8		TermID[30];
	guint8		tempchar;
	gint		tvb_RBRKT, tvb_LBRKT,  RBRKT_counter, LBRKT_counter;

	top_tree=tree;

	/* Initialize variables */
	tvb_len						= tvb_length(tvb);
	megaco_tree					= NULL;
	ti							= NULL;
	tvb_previous_offset			= 0;
	tvb_current_offset			= 0;
	tvb_offset					= 0;
	tvb_next_offset				= 0;
	tvb_command_start_offset	= 0;
	tvb_command_end_offset		= 0;
	tvb_RBRKT					= 0;
	tvb_LBRKT					= 0;
	RBRKT_counter				= 0;
	LBRKT_counter				= 0;

	/*
	 * Check to see whether we're really dealing with MEGACO by looking
	 * for the "MEGACO" string or a "!".This needs to be improved when supporting
	 * binary encodings. Bugfix add skipping of leading spaces.
	 */
	tvb_offset = tvb_skip_wsp(tvb, tvb_offset);
	/* Quick fix for MEGACO not following the RFC, hopfully not breaking any thing
	 * Turned out to be TPKT in case of TCP, added some code to handle that.
	 *
	 * tvb_offset = tvb_find_guint8(tvb, tvb_offset, 5, 'M');
	 */
	if(!tvb_get_nstringz0(tvb,tvb_offset,sizeof(word),word)) return;
	if (strncasecmp(word, "MEGACO", 6) != 0 && tvb_get_guint8(tvb, tvb_offset ) != '!'){
			return;
	}


	/* Display MEGACO in protocol column */
	if (check_col(pinfo->cinfo, COL_PROTOCOL))
		col_add_str(pinfo->cinfo, COL_PROTOCOL, "MEGACO");

	/* Build the info tree if we've been given a root */
	if (tree){
		/* Create megaco subtree */
		ti = proto_tree_add_item(tree,proto_megaco,tvb, 0, -1, FALSE);
		megaco_tree = proto_item_add_subtree(ti, ett_megaco);

	}
	if(global_megaco_dissect_tree)
		my_proto_tree_add_string = proto_tree_add_string;
	else
		my_proto_tree_add_string = proto_tree_add_string_hidden;

 	/*  Format of 'message' is = MegacopToken SLASH Version SEP mId SEP messageBody */
	/*  MegacopToken = "MEGACO" or "!"						*/
  	/*  According to H248.1-200205 Annex B Text encoding ( protocol version 2 )     */

	/* Find version */
	tvb_previous_offset = tvb_find_guint8(tvb, 0,
		tvb_len, '/');
	if (tvb_previous_offset == -1) {
		proto_tree_add_text(megaco_tree, tvb, 0, -1,
		    "Sorry, no \"/\" in the MEGACO header, I can't parse this packet");
		return;
	}
	tvb_previous_offset = tvb_previous_offset + 1;
	/* As version should follow /, just add 1, works till ver 9 */
	tvb_current_offset  = tvb_previous_offset + 1;


	tokenlen = tvb_current_offset - tvb_previous_offset;

	if (tree)
		my_proto_tree_add_string(megaco_tree, hf_megaco_version, tvb,
		tvb_previous_offset, tokenlen,
		tvb_format_text(tvb, tvb_previous_offset,
		tokenlen));
	/* Pos of version + 2 should take us past version + SEP					*/

	tvb_previous_offset = tvb_previous_offset + 2;
	/* in case of CRLF				*/
	if (tvb_get_guint8(tvb, tvb_current_offset ) == '\n')
		tvb_previous_offset++;
	if (tvb_get_guint8(tvb, tvb_current_offset ) == '\r')
		tvb_previous_offset++;

	/* mId should follow here,								
	 * mId = (( domainAddress / domainName ) [":" portNumber]) / mtpAddress / deviceName 	
	 * domainAddress = "[" (IPv4address / IPv6address) "]"	
	 * domainName = "<" (ALPHA / DIGIT) *63(ALPHA / DIGIT / "-" /".") ">"			
	 * mtpAddress = MTPToken LBRKT 4*8 (HEXDIG) RBRKT		
	 * MTPToken = ("MTP")									
	 * deviceName = pathNAME								
	 * pathNAME = ["*"] NAME *("/" / "*"/ ALPHA / DIGIT /"_" / "$" )["@" pathDomainName ]
	 */

	tokenlen = tvb_find_line_end( tvb, tvb_previous_offset, -1, &tvb_next_offset, FALSE);
	/* accept white spaces as SEParator too */
	if ( (tvb_current_offset=tvb_find_guint8(tvb, tvb_previous_offset, tokenlen, ' ')) != -1 ) {
		/* SEP after mID might be spaces only */
		tokenlen = tvb_current_offset-tvb_previous_offset;
		tvb_next_offset = tvb_skip_wsp(tvb, tvb_current_offset);
	}

   /* Att this point we should point to the "\n" ending the mId element
    * or to the next character after white space SEP 
	*/

	if (tree)
		my_proto_tree_add_string(megaco_tree, hf_megaco_mId, tvb,
		tvb_previous_offset, tokenlen,
		tvb_format_text(tvb, tvb_previous_offset,
		tokenlen));

	tvb_previous_offset = tvb_next_offset;

/* Next part is 										
 *	: messageBody = ( errorDescriptor / transactionList )					
 * 		errorDescriptor = ErrorToken EQUAL ErrorCode LBRKT [quotedString] RBRKT		
 * 			ErrorToken = ("Error" / "ER")						
 *
 *		transactionList = 1*( transactionRequest / transactionReply /			
 *					transactionPending / transactionResponseAck )		
 *
 *		transactionResponseAck = ResponseAckToken LBRKT 				 
 *			transactionAck*(COMMA transactionAck) RBRKT				
 *				ResponseAckToken = ("TransactionResponseAck"/ "K") 		
 *
 *		transactionPending = PendingToken EQUAL TransactionID LBRKT RBRKT		
 *			PendingToken = ("Pending" / "PN")					
 *
 *		transactionReply = ReplyToken EQUAL TransactionID LBRKT				
 *			[ ImmAckRequiredToken COMMA]( errorDescriptor / actionReplyList ) RBRKT 
 *			ReplyToken = ("Reply" / "P")						
 *
 *		transactionRequest = TransToken EQUAL TransactionID LBRKT			
 *			actionRequest *(COMMA actionRequest) RBRKT				
 *			TransToken = ("Transaction" / "T")					
 */

	tempchar = tvb_get_guint8(tvb, tvb_previous_offset );
	if ( (tempchar >= 'a')&& (tempchar <= 'z'))
		tempchar = tempchar - 0x20;

	switch ( tempchar ){
		/* errorDescriptor */
		case 'E':
			if (check_col(pinfo->cinfo, COL_INFO) )
			col_add_fstr(pinfo->cinfo, COL_INFO, "Error  ");
			tokenlen = tvb_len - tvb_previous_offset;
			if (tree) {
				my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
				tvb_previous_offset, tokenlen,
				"Error" );

				tvb_command_start_offset = tvb_previous_offset;
				dissect_megaco_errordescriptor(tvb, megaco_tree, tvb_len-1, tvb_command_start_offset);
			}
			return;
			break;
			/* transactionResponseAck 	
			 * transactionResponseAck = ResponseAckToken LBRKT transactionAck
             *                           *(COMMA transactionAck) RBRKT
			 * transactionAck = transactionID / (transactionID "-" transactionID)
			 */
		case 'K':
			tvb_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '{');
			tokenlen = tvb_offset - tvb_previous_offset;
			my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
				tvb_previous_offset, tokenlen,
				"TransactionResponseAck" );

			tvb_previous_offset = tvb_skip_wsp(tvb, tvb_offset+1);
			tvb_current_offset = tvb_find_guint8(tvb, tvb_offset+1, tvb_len, '}');
			tvb_current_offset = tvb_skip_wsp_return(tvb, tvb_current_offset)-1; /* cut last RBRKT */
			len = tvb_current_offset - tvb_previous_offset;

			if (check_col(pinfo->cinfo, COL_INFO) )
				col_add_fstr(pinfo->cinfo, COL_INFO, "%s TransactionResponseAck",
				tvb_format_text(tvb,tvb_previous_offset,len));
			if(tree)
				my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
				tvb_previous_offset, len,
				tvb_format_text(tvb,tvb_previous_offset,len));
				if(global_megaco_raw_text){
					tvb_raw_text_add(tvb, megaco_tree);
				}
			return;
			break;
		/* Pe and PN is transactionPending, P+"any char" is transactionReply */
		case 'P':
			tempchar = tvb_get_guint8(tvb, tvb_previous_offset + 1 );
			switch ( tempchar ){
				case 'e':
					tokenlen = 7;
					if (tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
					tvb_previous_offset, tokenlen,
					"Pending" );

					tvb_offset  = tvb_find_guint8(tvb, tvb_previous_offset, tvb_len, '=')+1;
					tvb_previous_offset = tvb_skip_wsp(tvb, tvb_offset);
					len = tvb_len - tvb_offset - 2;
					if (check_col(pinfo->cinfo, COL_INFO) )
					col_add_fstr(pinfo->cinfo, COL_INFO, "%s Pending",
					tvb_format_text(tvb,tvb_offset,len));

					if(tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
					tvb_previous_offset, tokenlen,
					tvb_format_text(tvb,tvb_offset,len));

				return;
				break;
				case 'N':
					tokenlen = 2;
					if (tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
					tvb_previous_offset, tokenlen,
					"Pending" );

					tvb_offset  = tvb_find_guint8(tvb, tvb_previous_offset, tvb_len, '=')+1;
					len = tvb_len - tvb_offset - 2;
					if (check_col(pinfo->cinfo, COL_INFO) )
					col_add_fstr(pinfo->cinfo, COL_INFO, "%s Pending",
					tvb_format_text(tvb,tvb_offset,len));

					if(tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
					tvb_previous_offset, tokenlen,
					tvb_format_text(tvb,tvb_offset,len));
					return;
					break;
				/* Reply */
   				default :
					tokenlen = 1;
					if (tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
					tvb_previous_offset, tokenlen,
					"Reply" );

					tvb_offset  = tvb_find_guint8(tvb, tvb_previous_offset, tvb_len, '=')+1;
					tvb_offset = tvb_skip_wsp(tvb, tvb_offset);
					tvb_current_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '{');
					tvb_current_offset  = tvb_skip_wsp_return(tvb, tvb_current_offset-1);
					len = tvb_current_offset - tvb_offset;

					if (check_col(pinfo->cinfo, COL_INFO) )
					col_add_fstr(pinfo->cinfo, COL_INFO, "%s Reply  ",
					tvb_format_text(tvb,tvb_offset,len));
					if(tree)
					my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
					tvb_offset, len,
					tvb_format_text(tvb,tvb_offset,len));
				break;
				}/* end switch */
			break; /* Case 'P' */
		/* transactionReply */
		case 'R':
			tokenlen = 5;
			if (tree)
			my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
			tvb_previous_offset, tokenlen,
			"Reply" );

			tvb_offset  = tvb_find_guint8(tvb, tvb_previous_offset, tvb_len, '=')+1;
			tvb_offset = tvb_skip_wsp(tvb, tvb_offset);
			tvb_current_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '{');
			tvb_current_offset  = tvb_skip_wsp_return(tvb, tvb_current_offset-1);
			len = tvb_current_offset - tvb_offset;

			if (check_col(pinfo->cinfo, COL_INFO) )
				col_add_fstr(pinfo->cinfo, COL_INFO, "%s Reply  ",
				tvb_format_text(tvb,tvb_offset,len));
			if(tree)
				my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
				tvb_offset, len,
				tvb_format_text(tvb,tvb_offset,len));
			break;
		/* TransactionRequest or TransactionResponseAck	*/

		case 'T':
			tokenlen = 1;
			if (tvb_get_guint8(tvb, tvb_previous_offset + 1 )!= 'r' )
			{
				/* TransactionRequest short notation */
			}
			else{					/* TransactionRequest or TransactionResponseAck	*/
				len = 22;			/* TransactionResponseAck is 22 characters      */
				tokenlen = 11;
				tvb_get_nstringz0(tvb,tvb_previous_offset,len+1,transaction);

 				if ( transaction[19] == 'A'){
					tvb_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '{')+1;
					tvb_offset = tvb_skip_wsp(tvb, tvb_offset);
					tvb_next_offset = tvb_find_guint8(tvb, tvb_offset, tvb_len, '}') - 1;
					tvb_next_offset = tvb_skip_wsp_return(tvb, tvb_next_offset);
					len = tvb_next_offset - tvb_offset;
					if (check_col(pinfo->cinfo, COL_INFO) )
						col_add_fstr(pinfo->cinfo, COL_INFO, "%s TransactionResponseAck",
						tvb_format_text(tvb,tvb_offset,len));
					if(tree)
						len = tvb_len - tvb_previous_offset;
						proto_tree_add_text(megaco_tree, tvb, tvb_previous_offset, -1,
							"%s",tvb_format_text(tvb, tvb_previous_offset, len));

						my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
										tvb_offset, (tvb_next_offset - tvb_offset),
										tvb_format_text(tvb,tvb_offset,(tvb_next_offset - tvb_offset)));
					if(global_megaco_raw_text){
						tvb_raw_text_add(tvb, megaco_tree);
						}
					return;
					break;
				}
			}/* else  */

			/* TransactionRequest 	*/
			if(tree)
			my_proto_tree_add_string(megaco_tree, hf_megaco_transaction, tvb,
				tvb_previous_offset, tokenlen,
				"Request" );
			tvb_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '=')+1;
			tvb_offset = tvb_skip_wsp(tvb, tvb_offset);
			tvb_current_offset  = tvb_find_guint8(tvb, tvb_offset, tvb_len, '{');
			tvb_current_offset  = tvb_skip_wsp_return(tvb, tvb_current_offset-1);
			len = tvb_current_offset - tvb_offset;
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_add_fstr(pinfo->cinfo, COL_INFO, "%s Request",
				tvb_format_text(tvb,tvb_offset,len));
			if(tree)
				my_proto_tree_add_string(megaco_tree, hf_megaco_transid, tvb,
				tvb_offset,len,
				tvb_format_text(tvb,tvb_offset,len));

			break;
		default :
			ti = proto_tree_add_item(tree,proto_megaco,tvb, 0, -1, FALSE);
			megaco_tree = proto_item_add_subtree(ti, ett_megaco);
			proto_tree_add_text(megaco_tree, tvb, 0, -1,
		    "Sorry, can't understand errorDescriptor / transactionList = %s, can't parse it pos %u",
                         tvb_format_text(tvb,tvb_previous_offset,2),tvb_previous_offset);
		return;
		break;
		} /* end switch */
/* 		Only these remains now									*/
/*		transactionReply = ReplyToken EQUAL TransactionID LBRKT					*/
/*			[ ImmAckRequiredToken COMMA]( errorDescriptor / actionReplyList ) RBRKT		*/
/*			ReplyToken = ("Reply" / "P")							*/

/*		transactionRequest = TransToken EQUAL TransactionID LBRKT				*/
/*			actionRequest *(COMMA actionRequest) RBRKT					*/
/*			TransToken = ("Transaction" / "T")						*/

/* Ready to here etxrab */
if(tree) {   /* Only do the rest if tree built */
		/* Find Context */
nextcontext:
		tvb_previous_offset = tvb_find_guint8(tvb, tvb_current_offset,
			tvb_len, '=')+1;
		tvb_previous_offset = tvb_skip_wsp(tvb, tvb_previous_offset);
		tvb_next_offset = tvb_find_guint8(tvb, tvb_previous_offset,
			tvb_len, '{');
		if (tvb_current_offset >= tvb_next_offset) {
			proto_tree_add_text(megaco_tree, tvb, 0, 0, "[ Parse error: Invalid offset ]");
			return;
		}
		tvb_current_offset = tvb_next_offset;


		tokenlen = tvb_current_offset - tvb_previous_offset;
		tempchar = tvb_get_guint8(tvb, tvb_previous_offset );

		if (tvb_get_guint8(tvb, tvb_current_offset-1 ) == ' '){
			tokenlen--;
		}

		switch ( tempchar ){
		case '$':
			my_proto_tree_add_string(megaco_tree, hf_megaco_Context, tvb,
				tvb_previous_offset, 1,
				"Choose one");
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_append_fstr(pinfo->cinfo, COL_INFO, " |=Choose one");
			break;
		case '*':
			my_proto_tree_add_string(megaco_tree, hf_megaco_Context, tvb,
				tvb_previous_offset, 1,
				"All");
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_append_fstr(pinfo->cinfo, COL_INFO, " |=All");
			break;
		case '-':
			proto_tree_add_text(megaco_tree, tvb, tvb_previous_offset, tokenlen, "Context: NULL" );
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_append_fstr(pinfo->cinfo, COL_INFO, " |=NULL");
			break;
		default:
			my_proto_tree_add_string(megaco_tree, hf_megaco_Context, tvb,
				tvb_previous_offset, tokenlen,
				tvb_format_text(tvb, tvb_previous_offset,
				tokenlen));
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_append_fstr(pinfo->cinfo, COL_INFO, " |=%s",tvb_format_text(tvb, tvb_previous_offset,tokenlen));
		}

		/* Find Commands */


		/* If transaction is ERROR the plugin will call the ERROR subroutine */
		if ( transaction[0] == 'E'){
			tvb_offset = tvb_find_guint8(tvb, 0, tvb_len, '/');
			tvb_command_start_offset = tvb_find_guint8(tvb, tvb_offset, tvb_len, 'E');
			dissect_megaco_errordescriptor(tvb, megaco_tree, tvb_len-1, tvb_command_start_offset);
			return;
		}

		else{

			/* If Transaction is is Request, Reply or Pending */

			tvb_command_start_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
			tvb_command_end_offset = tvb_command_start_offset;

			tvb_LBRKT = tvb_command_start_offset;
			tvb_RBRKT = tvb_command_start_offset;
		}


		/* The following loop find the individual contexts, commands and call the for every Descriptor a subroutine */

		do {
			tvb_command_end_offset = tvb_find_guint8(tvb, tvb_command_end_offset +1,
				tvb_len, ',');

			if ( tvb_command_end_offset == -1 ){
				tvb_command_end_offset = tvb_len;

			}

			/* checking how many left brackets are before the next comma */

			while ( tvb_find_guint8(tvb, tvb_LBRKT+1,tvb_len, '{') != -1
				&& (tvb_find_guint8(tvb, tvb_LBRKT+1,tvb_len, '{') < tvb_command_end_offset)){

				tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT+1,
					tvb_len, '{');

				LBRKT_counter++;
			}

			/* checking how many right brackets are before the next comma */

			while ( (tvb_find_guint8(tvb, tvb_RBRKT+1,tvb_len, '}') != -1 )
				&& (tvb_find_guint8(tvb, tvb_RBRKT+1,tvb_len, '}') < tvb_command_end_offset)
				&& LBRKT_counter != 0){

				tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
					tvb_len, '}');
				RBRKT_counter++;


			}

			/* If equal or more right brackets before the comma, one command is complete */

			if ( LBRKT_counter <= RBRKT_counter ){

				tvb_current_offset  = tvb_find_guint8(tvb, tvb_command_start_offset,
					tvb_len, '{');


				/* includes no descriptors */

				if ( LBRKT_counter == 0 ){

					tvb_current_offset = tvb_command_end_offset;

					/* the last command in a context */

					if ( tvb_find_guint8(tvb, tvb_command_start_offset, tvb_len, '}') < tvb_current_offset
						&& tvb_find_guint8(tvb, tvb_command_start_offset, tvb_len, '}') != -1){

						tvb_previous_offset  = tvb_find_guint8(tvb, tvb_command_start_offset,
							tvb_len, '}');


						tvb_previous_offset = tvb_skip_wsp_return(tvb, tvb_previous_offset -1);

						tokenlen =  tvb_previous_offset - tvb_command_start_offset;

					}

					/* not the last command in a context*/

					else{
						tvb_current_offset = tvb_skip_wsp_return(tvb, tvb_current_offset -1);

						tokenlen =  tvb_current_offset - tvb_command_start_offset;
					}
				}

				/* command includes descriptors */

				else{
					tvb_current_offset = tvb_skip_wsp_return(tvb, tvb_current_offset -1);

					tokenlen =  tvb_current_offset - tvb_command_start_offset;
				}

				/* if a next context is specified */

				if ( tvb_get_guint8(tvb, tvb_command_start_offset ) == 'C'){
					tvb_current_offset = tvb_command_start_offset;
					LBRKT_counter = 0;
					RBRKT_counter = 0;
					goto nextcontext;
				}

				/* creation of the megaco_tree_command_line additionally Command and Transaction ID will be printed in this line */

				sub_ti = proto_tree_add_item(megaco_tree,hf_megaco_command_line,tvb,tvb_command_start_offset,tokenlen, FALSE);
				megaco_tree_command_line = proto_item_add_subtree(sub_ti, ett_megaco_command_line);

				tvb_next_offset = tvb_command_start_offset + tokenlen;

				/* Additional value */

				if ( tvb_get_guint8(tvb, tvb_command_start_offset ) == 'O'){

					proto_tree_add_text(megaco_tree_command_line, tvb, tvb_command_start_offset, 2, "O- indicates an optional command" );
					tvb_command_start_offset = tvb_command_start_offset+2;

				}

				/* Additional value */

				if ( tvb_get_guint8(tvb, tvb_command_start_offset ) == 'W'){

					proto_tree_add_text(megaco_tree_command_line, tvb, tvb_command_start_offset, 2, "W- indicates a wildcarded response to a command" );
					tvb_command_start_offset = tvb_command_start_offset+2;

				}



				tvb_offset  = tvb_find_guint8(tvb, tvb_command_start_offset,
					tvb_len, '=');
				tvb_offset = tvb_skip_wsp_return(tvb, tvb_offset -1);
				tokenlen = tvb_offset - tvb_command_start_offset;

				tempchar = tvb_get_guint8(tvb, tvb_command_start_offset);
				if ( (tempchar >= 'a')&& (tempchar <= 'z'))
					tempchar = tempchar - 0x20;

				if ( tempchar != 'E' ){

					if ( tvb_get_guint8(tvb, 0 ) == '!'){

						switch ( tempchar ){

						case 'A':

							tempchar = tvb_get_guint8(tvb, tvb_command_start_offset+1);

							switch ( tempchar ){

							case 'V':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"AuditValue");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " AuditValue");
								break;

							case 'C':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"AuditCapability");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " AuditCapability");
								break;

							default:
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Add");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " Add");
								break;
							}
							break;

						case 'N':
							my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
								tvb_command_start_offset, tokenlen,
								"Notify");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " Notify");
							break;

						case 'M':

							tempchar = tvb_get_guint8(tvb, tvb_command_start_offset+1);

							switch ( tempchar ){
							case 'F':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Modify");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " Modify");
								break;

							case 'V':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Move");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " Move");
								break;
							}
							break;

						case 'P':
							/*
							PackagesToken	= ("Packages"	/ "PG")
							PendingToken	= ("Pending"	/ "PN")
							PriorityToken	= ("Priority"	/ "PR")
							ProfileToken	= ("Profile"	/ "PF")
							*/
							tempchar = tvb_get_guint8(tvb, tvb_command_start_offset+1);

							switch ( tempchar ){
							case 'G':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Packages");
								break;
							case 'N':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Pending");
								break;
							case 'R':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Priority");
								break;
							case 'F':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Profile");
								break;
							}
							break;

						case 'S':
							tempchar = tvb_get_guint8(tvb, tvb_command_start_offset+1);

							switch ( tempchar ){

							case 'C':
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"ServiceChange");
								break;

							default:
								my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
									tvb_command_start_offset, tokenlen,
									"Subtract");
								if (check_col(pinfo->cinfo, COL_INFO) )
									col_append_fstr(pinfo->cinfo, COL_INFO, " Subtract");
								break;
							}
							break;

						default:
							tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
							tvb_ensure_bytes_exist(tvb, tvb_previous_offset, tokenlen);
							proto_tree_add_string(megaco_tree, hf_megaco_error_Frame, tvb,
								tvb_previous_offset, tokenlen,
								"No Command detectable !");
							return;

							break;
						}
					}
					else{
						my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_command, tvb,
							tvb_command_start_offset, tokenlen,
							tvb_format_text(tvb, tvb_command_start_offset,
							tokenlen));
							if (check_col(pinfo->cinfo, COL_INFO) )
								col_append_fstr(pinfo->cinfo, COL_INFO, " %s",tvb_format_text(tvb, tvb_command_start_offset,tokenlen));
					}


					tvb_offset  = tvb_find_guint8(tvb, tvb_command_start_offset,
						tvb_len, '=');
					tvb_offset = tvb_skip_wsp(tvb, tvb_offset+1);
					tokenlen = tvb_next_offset - tvb_offset;

					tempchar = tvb_get_guint8(tvb, tvb_offset);

					switch ( tempchar ){

					case 'E':
						if ((tokenlen+1 > (int) sizeof(TermID)) || (tokenlen+1 <= 0)) {
							proto_tree_add_text(megaco_tree, tvb, 0, 0, "[ Parse error: Invalid TermID length (%d) ]", tokenlen+1);
							return;
						}
						tvb_get_nstringz0(tvb,tvb_offset,tokenlen+1,TermID);
						TermID[0] = 'e';
						my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_termid, tvb,
							tvb_offset, tokenlen,
							TermID);
						break;

					case '*':
						my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_termid, tvb,
							tvb_offset, tokenlen,
							"WildCard all");
							if (check_col(pinfo->cinfo, COL_INFO) )
								col_append_fstr(pinfo->cinfo, COL_INFO, "=*");
						break;

					case '$':
						my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_termid, tvb,
							tvb_offset, tokenlen,
							"WildCard any");
							if (check_col(pinfo->cinfo, COL_INFO) )
								col_append_fstr(pinfo->cinfo, COL_INFO, "=$");
						break;

					default:
						my_proto_tree_add_string(megaco_tree_command_line, hf_megaco_termid, tvb,
							tvb_offset, tokenlen,
							tvb_format_text(tvb, tvb_offset,
							tokenlen));
							if (check_col(pinfo->cinfo, COL_INFO) )
								col_append_fstr(pinfo->cinfo, COL_INFO, "=%s",tvb_format_text(tvb, tvb_offset,tokenlen));
						break;
					}

			}
			/* Dissect the Descriptors */


			if ( LBRKT_counter != 0 && tvb_current_offset != tvb_command_end_offset){

				tvb_descriptors_start_offset  = tvb_find_guint8(tvb, tvb_command_start_offset,
					tvb_len, '{');

				tvb_descriptors_end_offset = tvb_descriptors_start_offset;


				while ( LBRKT_counter > 0 ){

					tvb_descriptors_end_offset = tvb_find_guint8(tvb, tvb_descriptors_end_offset+1,
						tvb_len, '}');

					LBRKT_counter--;

				}

				tempchar = tvb_get_guint8(tvb, tvb_command_start_offset);

				if ( tempchar == 'E'){
					dissect_megaco_descriptors(tvb, megaco_tree_command_line, pinfo, tvb_command_start_offset-1,tvb_descriptors_end_offset);
				}
				else {
					dissect_megaco_descriptors(tvb, megaco_tree_command_line, pinfo, tvb_descriptors_start_offset,tvb_descriptors_end_offset);
				}
			}
			RBRKT_counter = 0;
			LBRKT_counter = 0;
			tvb_command_start_offset = tvb_skip_wsp(tvb, tvb_command_end_offset +1);
			tvb_LBRKT = tvb_command_start_offset;
			tvb_RBRKT = tvb_command_start_offset;

			}
		} while ( tvb_command_end_offset < tvb_len );
	}
	if(global_megaco_raw_text){
		tvb_raw_text_add(tvb, megaco_tree);
	}
}

static void
dissect_megaco_descriptors(tvbuff_t *tvb, proto_tree *megaco_tree_command_line, packet_info *pinfo, gint tvb_descriptors_start_offset, gint tvb_descriptors_end_offset)
{
	gint		tvb_len, len;
	gint		tvb_current_offset,tvb_previous_offset,tokenlen;
	gint		tvb_RBRKT, tvb_LBRKT,  RBRKT_counter, LBRKT_counter;
	guint8	  tempchar;
	tvb_len  	= tvb_length(tvb);


	len				= 0;
	tvb_RBRKT		= 0;
	tvb_LBRKT		= 0;
	RBRKT_counter	= 0;
	LBRKT_counter	= 0;


	tokenlen = tvb_descriptors_end_offset - tvb_descriptors_start_offset;


	tvb_LBRKT = tvb_skip_wsp(tvb, tvb_descriptors_start_offset +1);

	tvb_previous_offset = tvb_LBRKT;
	tvb_RBRKT = tvb_descriptors_start_offset;



	do {


		tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
			tvb_len, '}');
		tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT,
			tvb_len, '{');

		tvb_current_offset 	= tvb_find_guint8(tvb, tvb_previous_offset,
			tvb_len, ',');

		if (tvb_current_offset == -1 ){
			tvb_current_offset = tvb_descriptors_end_offset;

		}
		if (tvb_current_offset <= tvb_previous_offset) {
			proto_tree_add_text(megaco_tree_command_line, tvb, 0, 0, "[ Parse error: Invalid offset ]");
			return;
		}



		/* Descriptor includes no parameters */

		if ( tvb_LBRKT > tvb_current_offset || tvb_LBRKT == -1 ){

			if ( tvb_current_offset > tvb_RBRKT ){
				tvb_current_offset = tvb_RBRKT;
			}

			tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;
		}

		/* Descriptor includes Parameters */
		if ( (tvb_current_offset > tvb_LBRKT && tvb_LBRKT != -1)){

			while ( tvb_LBRKT != -1 && tvb_RBRKT > tvb_LBRKT ){


				tvb_LBRKT  = tvb_find_guint8(tvb, tvb_LBRKT+1,
					tvb_len, '{');
				if ( tvb_LBRKT < tvb_RBRKT && tvb_LBRKT != -1)
					tvb_RBRKT  = tvb_find_guint8(tvb, tvb_RBRKT+1,
					tvb_len, '}');


			}

		}


		tempchar = tvb_get_guint8(tvb, tvb_previous_offset );
		if ( (tempchar >= 'a')&& (tempchar <= 'z'))
			tempchar = tempchar - 0x20;

		switch ( tempchar ){

		case 'M':
			tempchar = tvb_get_guint8(tvb, tvb_previous_offset+1 );
			switch ( tempchar ){

			case 'o':
				dissect_megaco_modemdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'D':
				dissect_megaco_modemdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'u':
				dissect_megaco_multiplexdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'X':
				dissect_megaco_multiplexdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'e':
				dissect_megaco_mediadescriptor(tvb, megaco_tree_command_line, pinfo, tvb_RBRKT, tvb_previous_offset);
				break;
			case ',':
				break;

			default:
				dissect_megaco_mediadescriptor(tvb, megaco_tree_command_line, pinfo, tvb_RBRKT, tvb_previous_offset);
				break;
			}
			break;

		case 'S':
			tempchar = tvb_get_guint8(tvb, tvb_previous_offset+1 );
			switch ( tempchar ){
			case 'i':
				dissect_megaco_signaldescriptor(tvb, pinfo, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'G':
				dissect_megaco_signaldescriptor(tvb, pinfo, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'e':
				dissect_megaco_servicechangedescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'V':
				dissect_megaco_servicechangedescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'C':
				dissect_megaco_servicechangedescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 't':
				dissect_megaco_statisticsdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;

			case 'A':
				dissect_megaco_statisticsdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
				break;
			default:
				tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
				proto_tree_add_string(megaco_tree_command_line, hf_megaco_error_Frame, tvb,
					tvb_previous_offset, tokenlen,
					"No Descriptor detectable !");
				break;
			}
			break;

		case 'E':
			tempchar = tvb_get_guint8(tvb, tvb_previous_offset+1 );
			if ( tempchar == 'r' || tempchar == 'R'){

				if (  tvb_get_guint8(tvb, tvb_skip_wsp(tvb, tvb_RBRKT +1)) == ';'){
					tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1, tvb_len, '}');
					tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_RBRKT -1)-1;
				}
				dissect_megaco_errordescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			}
			else{
				dissect_megaco_eventsdescriptor(tvb, pinfo, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			}
			break;

		case 'A':
			dissect_megaco_auditdescriptor(tvb, megaco_tree_command_line, pinfo, tvb_RBRKT, tvb_previous_offset);
			break;

		case 'D':
			dissect_megaco_digitmapdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			break;

		case 'O':
			dissect_megaco_observedeventsdescriptor(tvb, pinfo, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			break;

		case 'T':
			dissect_megaco_topologydescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			break;

		case 'P':
			dissect_megaco_Packagesdescriptor(tvb, megaco_tree_command_line, tvb_RBRKT, tvb_previous_offset);
			break;

		default:
			tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
			proto_tree_add_string(megaco_tree_command_line, hf_megaco_error_Frame, tvb,
				tvb_previous_offset, tokenlen,
				"No Descriptor detectable !");
			break;

	}


	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	tvb_current_offset  	= tvb_find_guint8(tvb, tvb_RBRKT,
		tvb_len, ',');
	if (tvb_current_offset == -1 ){
		tvb_current_offset = tvb_descriptors_end_offset;
	}
	tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);
	tvb_LBRKT = tvb_previous_offset;
	tvb_RBRKT = tvb_previous_offset;


	} while ( tvb_current_offset < tvb_descriptors_end_offset );

}

static void
dissect_megaco_modemdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;



	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_modem_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}
static void
dissect_megaco_multiplexdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_multiplex_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}

/* mediaDescriptor = MediaToken LBRKT mediaParm *(COMMA mediaParm) RBRKT								
 *	MediaToken = ("Media" / "M")													
 *																	
 *		mediaParm = (streamParm / streamDescriptor /terminationStateDescriptor)							
 *																	
 *	; at-most one terminationStateDescriptor											
 *	; and either streamParm(s) or streamDescriptor(s) but not both									
 *			streamParm = ( localDescriptor / remoteDescriptor /localControlDescriptor )					
 *				localDescriptor = LocalToken LBRKT octetString RBRKT							
 *							LocalToken = ("Local" / "L")							
 *							octetString = *(nonEscapeChar)							
 *									nonEscapeChar = ( "\}" / %x01-7C / %x7E-FF )			
 *				remoteDescriptor = RemoteToken LBRKT octetString RBRKT							
 *							RemoteToken = ("Remote" / "R")							
 *				localControlDescriptor = LocalControlToken LBRKT localParm*(COMMA localParm) RBRKT			
 *							LocalControlToken = ("LocalControl" / "O")					
 *							localParm = ( streamMode / propertyParm / reservedValueMode			
 *			streamDescriptor = StreamToken EQUAL StreamID LBRKT streamParm*(COMMA streamParm) RBRKT				
 *							StreamToken = ("Stream" / "ST")							
 *			terminationStateDescriptor = TerminationStateToken LBRKTterminationStateParm 					
 *								*( COMMA terminationStateParm ) RBRKT					
 *							TerminationStateToken = ("TerminationState" / "TS")				
 *							terminationStateParm =(propertyParm / serviceStates / eventBufferControl )	
 */

static void
dissect_megaco_mediadescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,packet_info *pinfo,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;
	gint	tvb_next_offset, tvb_current_offset, tvb_offset, tvb_help_offset;
	guint8	tempchar;


	proto_tree  *megaco_mediadescriptor_tree, *megaco_mediadescriptor_ti;

	tokenlen			= 0;
	tvb_next_offset			= 0;
	tvb_current_offset		= 0;
	tvb_offset			= 0;
	tvb_help_offset			= 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;


	megaco_mediadescriptor_ti = proto_tree_add_text(megaco_tree_command_line,tvb,tvb_previous_offset,tokenlen,"Media Descriptor");
	megaco_mediadescriptor_tree = proto_item_add_subtree(megaco_mediadescriptor_ti, ett_megaco_mediadescriptor);

	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '=');
	tokenlen = tvb_current_offset  - tvb_previous_offset -1;
	proto_tree_add_text(megaco_mediadescriptor_tree, tvb,	tvb_previous_offset, tokenlen,
		"%s",	tvb_format_text(tvb, tvb_previous_offset,	tokenlen));

	tvb_next_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');
	/* If a StreamID is present */

	if ( tvb_find_guint8(tvb, tvb_next_offset+1, tvb_RBRKT, '{') > tvb_current_offset && tvb_current_offset > tvb_previous_offset ){
		tvb_next_offset = tvb_find_guint8(tvb, tvb_next_offset+1, tvb_RBRKT, '{');
		tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);

		tvb_offset = tvb_skip_wsp_return(tvb, tvb_next_offset-2);
		tokenlen =  tvb_offset - tvb_current_offset;

		proto_tree_add_string(megaco_mediadescriptor_tree, hf_megaco_streamid, tvb,
			tvb_current_offset, tokenlen,
			tvb_format_text(tvb, tvb_current_offset,
			tokenlen));
	}
	tvb_current_offset = tvb_next_offset ;



	while ( tvb_find_guint8(tvb, tvb_current_offset+1 , tvb_RBRKT, '{') != -1 && tvb_find_guint8(tvb, tvb_current_offset+1 , tvb_RBRKT, '{') < tvb_RBRKT && tvb_next_offset != -1){

		tvb_help_offset = tvb_next_offset;
		tvb_current_offset = tvb_find_guint8(tvb, tvb_current_offset+1 , tvb_RBRKT, '{');
		tvb_next_offset = tvb_find_guint8(tvb, tvb_current_offset+1 , tvb_RBRKT, '}');
		tvb_offset = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;

		if ( (tvb_next_offset - tvb_current_offset ) > 3 ){
			tvb_next_offset = tvb_skip_wsp_return(tvb, tvb_next_offset-1);
			tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
		}

		tempchar = tvb_get_guint8(tvb, tvb_offset);

		switch ( tempchar ){

		case 'R':
			/* Remote Descriptor in short message encoding */
			dissect_megaco_Remotedescriptor(tvb,megaco_mediadescriptor_tree, pinfo, tvb_next_offset, tvb_current_offset);
			break;

		case 'L':
			/* Local Descriptor in short message encoding */
			dissect_megaco_Localdescriptor(tvb,megaco_mediadescriptor_tree , pinfo, tvb_next_offset, tvb_current_offset);
			break;

		case 'O':
			/* Local Control Descriptor in short message encoding */
			dissect_megaco_LocalControldescriptor(tvb,megaco_mediadescriptor_tree, pinfo , tvb_next_offset, tvb_current_offset);
			break;

		case 'S':
			/* Termination State Descriptor in short message encoding */
			dissect_megaco_TerminationStatedescriptor(tvb,megaco_mediadescriptor_tree , tvb_next_offset, tvb_current_offset);
			break;

		case 'l':
			/* Local or Local Control Descriptor in long message encoding */
			if (tvb_get_guint8(tvb, tvb_offset-1) == 'a'){
				dissect_megaco_Localdescriptor(tvb,megaco_mediadescriptor_tree , pinfo, tvb_next_offset, tvb_current_offset);
			}
			else{
				dissect_megaco_LocalControldescriptor(tvb,megaco_mediadescriptor_tree, pinfo , tvb_next_offset, tvb_current_offset);
			}
			break;

		case 'e':
			/* Remote or Termination State Descriptor in long message encoding */

			if (tvb_get_guint8(tvb, tvb_offset-2) == 'a'){
				dissect_megaco_TerminationStatedescriptor(tvb,megaco_mediadescriptor_tree , tvb_next_offset, tvb_current_offset);
			}
			else {
				dissect_megaco_Remotedescriptor(tvb,megaco_mediadescriptor_tree , pinfo, tvb_next_offset, tvb_current_offset);
			}

			break;

		default:

			if ( tvb_find_guint8(tvb, tvb_help_offset, tvb_RBRKT, '{') > tvb_find_guint8(tvb, tvb_help_offset, tvb_RBRKT, '=')){

				tvb_help_offset = tvb_find_guint8(tvb, tvb_help_offset, tvb_RBRKT, '=');
				tvb_help_offset = tvb_skip_wsp(tvb, tvb_help_offset +1);

				tokenlen = tvb_offset - tvb_help_offset + 1;

				proto_tree_add_string(megaco_mediadescriptor_tree, hf_megaco_streamid, tvb,
					tvb_help_offset, tokenlen,
					tvb_format_text(tvb, tvb_help_offset,
					tokenlen));

			}
			else {
				tokenlen =  (tvb_RBRKT+1) - tvb_offset;
				proto_tree_add_string(megaco_mediadescriptor_tree, hf_megaco_error_Frame, tvb,
					tvb_offset, tokenlen,
					"No Descriptor detectable !");
			}
			break;

		}
	}
}

static void
dissect_megaco_h245(tvbuff_t *tvb, packet_info *pinfo, proto_tree *megaco_tree, gint offset, gint len, gchar *msg)
{
	proto_item *item;
	proto_tree *tree;
	guint8 buf[10240];

	item=proto_tree_add_string(megaco_tree, hf_megaco_h245, tvb,
		offset, len, msg );
	tree = proto_item_add_subtree(item, ett_megaco_h245);

	/* arbitrary maximum length */
	if(len<20480){
		int i;
		tvbuff_t *h245_tvb;

		/* first, skip to where the encoded pdu starts, this is
		   the first hex digit after the '=' char.
		*/
		while(1){
			if((*msg==0)||(*msg=='\n')){
				return;
			}
			if(*msg=='='){
				msg++;
				break;
			}
			msg++;
		}
		while(1){
			if((*msg==0)||(*msg=='\n')){
				return;
			}
			if( ((*msg>='0')&&(*msg<='9'))
			||  ((*msg>='a')&&(*msg<='f'))
			||  ((*msg>='A')&&(*msg<='F'))){
				break;
			}
			msg++;
		}
		i=0;
		while( ((*msg>='0')&&(*msg<='9'))
		     ||((*msg>='a')&&(*msg<='f'))
		     ||((*msg>='A')&&(*msg<='F'))  ){
			int val;
			if((*msg>='0')&&(*msg<='9')){
				val=(*msg)-'0';
			} else if((*msg>='a')&&(*msg<='f')){
				val=(*msg)-'a'+10;
			} else if((*msg>='A')&&(*msg<='F')){
				val=(*msg)-'A'+10;
			} else {
				return;
			}
			val<<=4;
			msg++;
			if((*msg>='0')&&(*msg<='9')){
				val|=(*msg)-'0';
			} else if((*msg>='a')&&(*msg<='f')){
				val|=(*msg)-'a'+10;
			} else if((*msg>='A')&&(*msg<='F')){
				val|=(*msg)-'A'+10;
			} else {
				return;
			}
			msg++;

			buf[i]=(guint8)val;
			i++;
		}
		if(i==0){
			return;
		}
		h245_tvb = tvb_new_real_data(buf,i,i);
		tvb_set_child_real_data_tvbuff(tvb,h245_tvb);
		add_new_data_source(pinfo, h245_tvb, "H.245 over MEGACO");
		/* should go through a handle, however,  the two h245 entry
		   points are different, one is over tpkt and the other is raw
		*/
		call_dissector(h245_handle, h245_tvb, pinfo, top_tree);
/*		dissect_h245_MultimediaSystemControlMessage(h245_tvb, pinfo, tree);*/
	}
}


static void
dissect_megaco_eventsdescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint tokenlen, tvb_current_offset, tvb_next_offset, tvb_help_offset;
	gint tvb_events_end_offset, tvb_events_start_offset, tvb_LBRKT;
	proto_tree  *megaco_eventsdescriptor_tree, *megaco_eventsdescriptor_ti;

	guint8 tempchar;
	gint requested_event_start_offset, requested_event_end_offset;
	proto_tree	*megaco_requestedevent_tree, *megaco_requestedevent_ti;

	tokenlen						= 0;
	tvb_current_offset				= 0;
	tvb_next_offset					= 0;
	tvb_help_offset					= 0;
	tvb_events_end_offset			= 0;
	tvb_events_start_offset			= 0;
	tvb_help_offset					= 0;
	requested_event_start_offset	= 0;
	requested_event_end_offset		= 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	megaco_eventsdescriptor_ti = proto_tree_add_item(megaco_tree_command_line,hf_megaco_events_descriptor,tvb,tvb_previous_offset,tokenlen, FALSE);
	megaco_eventsdescriptor_tree = proto_item_add_subtree(megaco_eventsdescriptor_ti, ett_megaco_eventsdescriptor);



	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '=');
	tvb_next_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');

	if ( tvb_current_offset < tvb_RBRKT && tvb_current_offset != -1 ){

		tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
		tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_next_offset-1);

		tokenlen =  tvb_help_offset - tvb_current_offset;

		proto_tree_add_string(megaco_eventsdescriptor_tree, hf_megaco_requestid, tvb,
			tvb_current_offset, tokenlen,
			tvb_format_text(tvb, tvb_current_offset,
			tokenlen));

		tvb_events_end_offset   = tvb_RBRKT;
		tvb_events_start_offset = tvb_previous_offset;

		tvb_RBRKT = tvb_next_offset+1;
		tvb_LBRKT = tvb_next_offset+1;
		tvb_previous_offset = tvb_skip_wsp(tvb, tvb_next_offset+1);


		do {

			tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
				tvb_events_end_offset, '}');
			tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT,
				tvb_events_end_offset, '{');

			tvb_current_offset 	= tvb_find_guint8(tvb, tvb_previous_offset,
				tvb_events_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_events_end_offset){
				tvb_current_offset = tvb_events_end_offset;
			}


			/* Descriptor includes no parameters */

			if ( tvb_LBRKT > tvb_current_offset || tvb_LBRKT == -1 ){

				tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;
			}

			/* Descriptor includes Parameters */

			if ( (tvb_current_offset > tvb_LBRKT && tvb_LBRKT != -1)){

				while ( tvb_LBRKT != -1 && tvb_RBRKT > tvb_LBRKT ){

					tvb_LBRKT  = tvb_find_guint8(tvb, tvb_LBRKT+1,
						tvb_events_end_offset, '{');
					if ( tvb_LBRKT < tvb_RBRKT && tvb_LBRKT != -1)
						tvb_RBRKT  = tvb_find_guint8(tvb, tvb_RBRKT+1,
						tvb_events_end_offset, '}');
				}

			}

			tvb_help_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_events_end_offset, '{');

			/* if there are eventparameter  */

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){

				requested_event_start_offset = tvb_help_offset;
				requested_event_end_offset	 = tvb_RBRKT;
				tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_help_offset-1);
				tokenlen = tvb_help_offset - tvb_previous_offset;
			}
			/* no parameters */
			else {
				tokenlen = tvb_RBRKT+1 - tvb_previous_offset;
			}

			megaco_requestedevent_ti = proto_tree_add_item(megaco_eventsdescriptor_tree,hf_megaco_pkgdname,tvb,tvb_previous_offset,tokenlen, FALSE);
			megaco_requestedevent_tree = proto_item_add_subtree(megaco_requestedevent_ti, ett_megaco_requestedevent);

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){

				tvb_help_offset = tvb_skip_wsp(tvb, requested_event_start_offset +1);
				tempchar = tvb_get_guint8(tvb, tvb_help_offset);

				requested_event_start_offset = tvb_skip_wsp(tvb, requested_event_start_offset +1);
				requested_event_end_offset = tvb_skip_wsp_return(tvb, requested_event_end_offset-1);

				if ( tempchar == 'D' ){
					dissect_megaco_digitmapdescriptor(tvb, megaco_requestedevent_tree, requested_event_end_offset, requested_event_start_offset);
				}
				else{
					gchar *msg;

					tokenlen = 	requested_event_end_offset - requested_event_start_offset;
					msg=tvb_format_text(tvb,requested_event_start_offset, tokenlen);
					if(!strncmp("h245", msg, 4)){
						dissect_megaco_h245(tvb, pinfo, megaco_requestedevent_tree, requested_event_start_offset, tokenlen, msg);
					} else {
						proto_tree_add_text(megaco_requestedevent_tree, tvb, requested_event_start_offset, tokenlen,
							"%s", msg);
					}
				}

			}

			tvb_current_offset  = tvb_find_guint8(tvb, tvb_RBRKT,
				tvb_events_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_events_end_offset ){
				tvb_current_offset = tvb_events_end_offset;
			}

			tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);

			tvb_LBRKT = tvb_previous_offset;
			tvb_RBRKT = tvb_previous_offset;

		} while ( tvb_current_offset < tvb_events_end_offset );
	}
}

static void
dissect_megaco_signaldescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint tokenlen, tvb_current_offset, tvb_next_offset, tvb_help_offset;
	gint tvb_signals_end_offset, tvb_signals_start_offset, tvb_LBRKT;
	proto_tree  *megaco_signalsdescriptor_tree, *megaco_signalsdescriptor_ti;

	gint requested_signal_start_offset, requested_signal_end_offset;
	proto_tree	*megaco_requestedsignal_tree, *megaco_requestedsignal_ti;

	tokenlen						= 0;
	tvb_current_offset				= 0;
	tvb_next_offset					= 0;
	tvb_help_offset					= 0;
	tvb_signals_end_offset			= 0;
	tvb_signals_start_offset		= 0;
	tvb_LBRKT						= 0;
	requested_signal_start_offset	= 0;
	requested_signal_end_offset		= 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	megaco_signalsdescriptor_ti = proto_tree_add_item(megaco_tree_command_line,hf_megaco_signal_descriptor,tvb,tvb_previous_offset,tokenlen, FALSE);
	megaco_signalsdescriptor_tree = proto_item_add_subtree(megaco_signalsdescriptor_ti, ett_megaco_signalsdescriptor);

	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');
	tvb_next_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);
	if (check_col(pinfo->cinfo, COL_INFO) )
		col_append_fstr(pinfo->cinfo, COL_INFO, " (Signal:%s)",tvb_format_text(tvb, tvb_current_offset,tokenlen-tvb_current_offset+tvb_previous_offset));

	tvb_signals_end_offset   = tvb_RBRKT;
	tvb_signals_start_offset = tvb_previous_offset;

	if ( tvb_current_offset < tvb_RBRKT && tvb_current_offset != -1 && tvb_next_offset != tvb_signals_end_offset){


		tvb_RBRKT = tvb_next_offset+1;
		tvb_LBRKT = tvb_next_offset+1;
		tvb_previous_offset = tvb_next_offset;


		do {

			tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
				tvb_signals_end_offset, '}');
			tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT,
				tvb_signals_end_offset, '{');

			tvb_current_offset 	= tvb_find_guint8(tvb, tvb_previous_offset,
				tvb_signals_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_signals_end_offset){
				tvb_current_offset = tvb_signals_end_offset;
			}


			/* Descriptor includes no parameters */

			if ( tvb_LBRKT > tvb_current_offset || tvb_LBRKT == -1 ){

				tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;
			}

			/* Descriptor includes Parameters */

			if ( (tvb_current_offset > tvb_LBRKT && tvb_LBRKT != -1)){

				while ( tvb_LBRKT != -1 && tvb_RBRKT > tvb_LBRKT ){

					tvb_LBRKT  = tvb_find_guint8(tvb, tvb_LBRKT+1,
						tvb_signals_end_offset, '{');
					if ( tvb_LBRKT < tvb_RBRKT && tvb_LBRKT != -1)
						tvb_RBRKT  = tvb_find_guint8(tvb, tvb_RBRKT+1,
						tvb_signals_end_offset, '}');
				}

			}

			tvb_help_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_signals_end_offset, '{');

			/* if there are signalparameter  */

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){

				requested_signal_start_offset = tvb_help_offset;
				requested_signal_end_offset	 = tvb_RBRKT;
				tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_help_offset-1);
				tokenlen = tvb_help_offset - tvb_previous_offset;
			}
			/* no parameters */
			else {
				tokenlen = tvb_RBRKT+1 - tvb_previous_offset;
			}


			megaco_requestedsignal_ti = proto_tree_add_item(megaco_signalsdescriptor_tree,hf_megaco_pkgdname,tvb,tvb_previous_offset,tokenlen, FALSE);
			megaco_requestedsignal_tree = proto_item_add_subtree(megaco_requestedsignal_ti, ett_megaco_requestedsignal);

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){
				gchar *msg;

				requested_signal_start_offset = tvb_skip_wsp(tvb, requested_signal_start_offset +1);
				requested_signal_end_offset = tvb_skip_wsp_return(tvb, requested_signal_end_offset-1);

				tokenlen = 	requested_signal_end_offset - requested_signal_start_offset;

				msg=tvb_format_text(tvb,requested_signal_start_offset, tokenlen+1);
				if(!strncmp("h245", msg, 4)){
					dissect_megaco_h245(tvb, pinfo, megaco_requestedsignal_tree, requested_signal_start_offset, tokenlen, msg);
				} else {
					proto_tree_add_text(megaco_requestedsignal_tree, tvb, requested_signal_start_offset, tokenlen,
						"%s", msg);
				}

			}

			tvb_current_offset  = tvb_find_guint8(tvb, tvb_RBRKT,
				tvb_signals_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_signals_end_offset || tvb_current_offset < tvb_previous_offset){
				tvb_current_offset = tvb_signals_end_offset;
			}

			tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);

			tvb_LBRKT = tvb_previous_offset;
			tvb_RBRKT = tvb_previous_offset;

		} while ( tvb_current_offset < tvb_signals_end_offset );
	}


}
static void
dissect_megaco_auditdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line, packet_info *pinfo,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;
	proto_tree  *megaco_auditdescriptor_tree, *megaco_auditdescriptor_ti;

	tokenlen = 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	megaco_auditdescriptor_ti = proto_tree_add_item(megaco_tree_command_line,hf_megaco_audit_descriptor,tvb,tvb_previous_offset,tokenlen, FALSE);
	megaco_auditdescriptor_tree = proto_item_add_subtree(megaco_auditdescriptor_ti, ett_megaco_auditdescriptor);


	tvb_previous_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');

	if ( tvb_skip_wsp(tvb, tvb_previous_offset +1) != tvb_RBRKT ){
		dissect_megaco_descriptors(tvb, megaco_auditdescriptor_tree, pinfo, tvb_previous_offset,tvb_RBRKT);
	}
}
static void
dissect_megaco_servicechangedescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_servicechange_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}
static void
dissect_megaco_digitmapdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;

	tokenlen =  tvb_RBRKT - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_digitmap_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}
static void
dissect_megaco_statisticsdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_statistics_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}
static void
dissect_megaco_observedeventsdescriptor(tvbuff_t *tvb, packet_info *pinfo, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint tokenlen, tvb_current_offset, tvb_next_offset, tvb_help_offset;
	gint tvb_observedevents_end_offset, tvb_observedevents_start_offset, tvb_LBRKT;
	proto_tree  *megaco_observedeventsdescriptor_tree, *megaco_observedeventsdescriptor_ti;

	guint8 tempchar;
	gint requested_event_start_offset, requested_event_end_offset, param_start_offset, param_end_offset;
	proto_tree	*megaco_observedevent_tree, *megaco_observedevent_ti;

	tokenlen						= 0;
	tvb_current_offset				= 0;
	tvb_next_offset					= 0;
	tvb_help_offset					= 0;
	tvb_observedevents_end_offset	= 0;
	tvb_observedevents_start_offset	= 0;
	tvb_LBRKT						= 0;
	requested_event_start_offset	= 0;
	requested_event_end_offset	= 0;



	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	megaco_observedeventsdescriptor_ti = proto_tree_add_item(megaco_tree_command_line,hf_megaco_observedevents_descriptor,tvb,tvb_previous_offset,tokenlen, FALSE);
	megaco_observedeventsdescriptor_tree = proto_item_add_subtree(megaco_observedeventsdescriptor_ti, ett_megaco_observedeventsdescriptor);



	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '=');
	tvb_next_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');

	if ( tvb_current_offset < tvb_RBRKT && tvb_current_offset != -1 ){

		tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
		tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_next_offset-1);

		tokenlen =  tvb_help_offset - tvb_current_offset;

		proto_tree_add_string(megaco_observedeventsdescriptor_tree, hf_megaco_requestid, tvb,
			tvb_current_offset, tokenlen,
			tvb_format_text(tvb, tvb_current_offset,
			tokenlen));

		tvb_observedevents_end_offset   = tvb_RBRKT;
		tvb_observedevents_start_offset = tvb_previous_offset;

		tvb_RBRKT = tvb_next_offset+1;
		tvb_LBRKT = tvb_next_offset+1;
		tvb_previous_offset = tvb_skip_wsp(tvb, tvb_next_offset+1);


		do {

			tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
				tvb_observedevents_end_offset, '}');
			tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT,
				tvb_observedevents_end_offset, '{');

			tvb_current_offset 	= tvb_find_guint8(tvb, tvb_previous_offset,
				tvb_observedevents_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_observedevents_end_offset){
				tvb_current_offset = tvb_observedevents_end_offset;
			}


			/* Descriptor includes no parameters */

			if ( tvb_LBRKT > tvb_current_offset || tvb_LBRKT == -1 ){

				tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;
			}

			/* Descriptor includes Parameters */

			if ( (tvb_current_offset > tvb_LBRKT && tvb_LBRKT != -1)){

				while ( tvb_LBRKT != -1 && tvb_RBRKT > tvb_LBRKT ){

					tvb_LBRKT  = tvb_find_guint8(tvb, tvb_LBRKT+1,
						tvb_observedevents_end_offset, '{');
					if ( tvb_LBRKT < tvb_RBRKT && tvb_LBRKT != -1){
						tvb_RBRKT  = tvb_find_guint8(tvb, tvb_RBRKT+1,
							tvb_observedevents_end_offset, '}');
					}
				}

			}

			tvb_help_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_observedevents_end_offset, '{');

			/* if there are eventparameter  */

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){

				requested_event_start_offset = tvb_help_offset;
				requested_event_end_offset	 = tvb_RBRKT;
				tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_help_offset-1);
				tokenlen = tvb_help_offset - tvb_previous_offset;
			}
			/* no parameters */
			else {
				tokenlen = tvb_RBRKT+1 - tvb_previous_offset;
			}

			megaco_observedevent_ti = proto_tree_add_item(megaco_observedeventsdescriptor_tree,hf_megaco_pkgdname,tvb,tvb_previous_offset,tokenlen, FALSE);
			megaco_observedevent_tree = proto_item_add_subtree(megaco_observedevent_ti, ett_megaco_observedevent);

			if ( tvb_help_offset < tvb_RBRKT && tvb_help_offset != -1 ){

				tvb_help_offset = tvb_skip_wsp(tvb, requested_event_start_offset +1);
				tempchar = tvb_get_guint8(tvb, tvb_help_offset);

				requested_event_start_offset = tvb_skip_wsp(tvb, requested_event_start_offset +1)-1;
				requested_event_end_offset = tvb_skip_wsp_return(tvb, requested_event_end_offset-1);

				tvb_help_offset = requested_event_start_offset;

				do {
					gchar *msg;

					param_start_offset = tvb_skip_wsp(tvb, tvb_help_offset+1);

					tvb_help_offset = tvb_find_guint8(tvb, tvb_help_offset+1,requested_event_end_offset, ',');

					if ( tvb_help_offset > requested_event_end_offset || tvb_help_offset == -1){
						tvb_help_offset = requested_event_end_offset;
					}

					param_end_offset = tvb_skip_wsp(tvb, tvb_help_offset-1);

					tokenlen = 	param_end_offset - param_start_offset+1;
					msg=tvb_format_text(tvb,param_start_offset, tokenlen);
					if(!strncmp("h245", msg, 4)){
						dissect_megaco_h245(tvb, pinfo, megaco_observedevent_tree, param_start_offset, tokenlen, msg);
					} else {
						proto_tree_add_text(megaco_observedevent_tree, tvb, param_start_offset, tokenlen,
							"%s", msg);
					}


				} while ( tvb_help_offset < requested_event_end_offset );
			}

			tvb_previous_offset = tvb_current_offset;
			tvb_current_offset  = tvb_find_guint8(tvb, tvb_RBRKT,
				tvb_observedevents_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_observedevents_end_offset ){
				tvb_current_offset = tvb_observedevents_end_offset;
			}
			if (tvb_current_offset <= tvb_previous_offset) {
				proto_tree_add_text(megaco_observedevent_tree, tvb, 0, 0, "[ Parse error: Invalid offset ]");
				return;
			}

			tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);

			tvb_LBRKT = tvb_previous_offset;
			tvb_RBRKT = tvb_previous_offset;

		} while ( tvb_current_offset < tvb_observedevents_end_offset );
	}
}
static void
dissect_megaco_topologydescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 	tokenlen;

	tokenlen = 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;
	proto_tree_add_string(megaco_tree_command_line, hf_megaco_topology_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

}
static void
dissect_megaco_Packagesdescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint tokenlen, tvb_current_offset, tvb_next_offset, tvb_help_offset;
	gint tvb_packages_end_offset, tvb_packages_start_offset, tvb_LBRKT;
	proto_tree  *megaco_packagesdescriptor_tree, *megaco_packagesdescriptor_ti;

	tokenlen					= 0;
	tvb_current_offset			= 0;
	tvb_next_offset				= 0;
	tvb_help_offset				= 0;
	tvb_packages_end_offset		= 0;
	tvb_packages_start_offset	= 0;
	tvb_LBRKT					= 0;

	tokenlen =  (tvb_RBRKT+1) - tvb_previous_offset;

	megaco_packagesdescriptor_ti = proto_tree_add_item(megaco_tree_command_line,hf_megaco_packages_descriptor,tvb,tvb_previous_offset,tokenlen, FALSE);
	megaco_packagesdescriptor_tree = proto_item_add_subtree(megaco_packagesdescriptor_ti, ett_megaco_packagesdescriptor);



	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '=');
	tvb_next_offset = tvb_find_guint8(tvb, tvb_previous_offset, tvb_RBRKT, '{');

	if ( tvb_current_offset < tvb_RBRKT && tvb_current_offset != -1 ){

		tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
		tvb_help_offset = tvb_skip_wsp_return(tvb, tvb_next_offset-1);

		tokenlen =  tvb_help_offset - tvb_current_offset;

		proto_tree_add_string(megaco_packagesdescriptor_tree, hf_megaco_requestid, tvb,
			tvb_current_offset, tokenlen,
			tvb_format_text(tvb, tvb_current_offset,
			tokenlen));

		tvb_packages_end_offset   = tvb_RBRKT;
		tvb_packages_start_offset = tvb_previous_offset;

		tvb_RBRKT = tvb_next_offset+1;
		tvb_LBRKT = tvb_next_offset+1;
		tvb_previous_offset = tvb_skip_wsp(tvb, tvb_next_offset+1);


		do {

			tvb_RBRKT = tvb_find_guint8(tvb, tvb_RBRKT+1,
				tvb_packages_end_offset, '}');
			tvb_LBRKT = tvb_find_guint8(tvb, tvb_LBRKT,
				tvb_packages_end_offset, '{');

			tvb_current_offset 	= tvb_find_guint8(tvb, tvb_previous_offset,
				tvb_packages_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_packages_end_offset){
				tvb_current_offset = tvb_packages_end_offset;
			}


			/* Descriptor includes no parameters */

			if ( tvb_LBRKT > tvb_current_offset || tvb_LBRKT == -1 ){

				tvb_RBRKT = tvb_skip_wsp_return(tvb, tvb_current_offset-1)-1;
			}

			/* Descriptor includes Parameters */

			if ( (tvb_current_offset > tvb_LBRKT && tvb_LBRKT != -1)){

				while ( tvb_LBRKT != -1 && tvb_RBRKT > tvb_LBRKT ){

					tvb_LBRKT  = tvb_find_guint8(tvb, tvb_LBRKT+1,
						tvb_packages_end_offset, '{');
					if ( tvb_LBRKT < tvb_RBRKT && tvb_LBRKT != -1)
						tvb_RBRKT  = tvb_find_guint8(tvb, tvb_RBRKT+1,
						tvb_packages_end_offset, '}');
				}

			}

			tokenlen = tvb_RBRKT+1 - tvb_previous_offset;

			proto_tree_add_text(megaco_packagesdescriptor_tree, tvb, tvb_previous_offset, tokenlen,
				"%s", tvb_format_text(tvb,tvb_previous_offset,
				tokenlen));


			tvb_current_offset  	= tvb_find_guint8(tvb, tvb_RBRKT,
				tvb_packages_end_offset, ',');

			if (tvb_current_offset == -1 || tvb_current_offset > tvb_packages_end_offset ){
				tvb_current_offset = tvb_packages_end_offset;
			}

			tvb_previous_offset = tvb_skip_wsp(tvb, tvb_current_offset+1);

			tvb_LBRKT = tvb_previous_offset;
			tvb_RBRKT = tvb_previous_offset;

		} while ( tvb_current_offset < tvb_packages_end_offset );
	}

}
/* The list of error code values is fetched from http://www.iana.org/assignments/megaco-h248 	*/
/* 2003-08-28											*/

static const value_string MEGACO_error_code_vals[] = {

	{400, "Syntax error in message"},
	{401, "Protocol Error"},
	{402, "Unauthorized"},
	{403, "Syntax error in transaction request"},
	{406, "Version Not Supported"},
	{410, "Incorrect identifier"},
	{411, "The transaction refers to an unknown ContextId"},
	{412, "No ContextIDs available"},
	{421, "Unknown action or illegal combination of actions"},
	{422, "Syntax Error in Action"},
	{430, "Unknown TerminationID"},
	{431, "No TerminationID matched a wildcard"},
	{432, "Out of TerminationIDs or No TerminationID available"},
	{433, "TerminationID is already in a Context"},
	{434, "Max number of Terminations in a Context exceeded"},
	{435, "Termination ID is not in specified Context"},
	{440, "Unsupported or unknown Package"},
	{441, "Missing Remote or Local Descriptor"},
	{442, "Syntax Error in Command"},
	{443, "Unsupported or Unknown Command"},
	{444, "Unsupported or Unknown Descriptor"},
	{445, "Unsupported or Unknown Property"},
	{446, "Unsupported or Unknown Parameter"},
	{447, "Descriptor not legal in this command"},
	{448, "Descriptor appears twice in a command"},
	{450, "No such property in this package"},
	{451, "No such event in this package"},
	{452, "No such signal in this package"},
	{453, "No such statistic in this package"},
	{454, "No such parameter value in this package"},
	{455, "Property illegal in this Descriptor"},
	{456, "Property appears twice in this Descriptor"},
	{457, "Missing parameter in signal or event"},
	{458, "Unexpected Event/Request ID"},
	{459, "Unsupported or Unknown Profile"},
	{471, "Implied Add for Multiplex failure"},

	{500, "Internal software Failure in MG"},
	{501, "Not Implemented"},
	{502, "Not ready."},
	{503, "Service Unavailable"},
	{504, "Command Received from unauthorized entity"},
	{505, "Transaction Request Received before a Service Change Reply has been received"},
	{506, "Number of Transaction Pendings Exceeded"},
	{510, "Insufficient resources"},
	{512, "Media Gateway unequipped to detect requested Event"},
	{513, "Media Gateway unequipped to generate requested Signals"},
	{514, "Media Gateway cannot send the specified announcement"},
	{515, "Unsupported Media Type"},
	{517, "Unsupported or invalid mode"},
	{518, "Event buffer full"},
	{519, "Out of space to store digit map"},
	{520, "Digit Map undefined in the MG"},
	{521, "Termination is ServiceChangeing"},
	{526, "Insufficient bandwidth"},
	{529, "Internal hardware failure in MG"},
	{530, "Temporary Network failure"},
	{531, "Permanent Network failure"},
	{532, "Audited Property, Statistic, Event or Signal does not exist"},
	{533, "Response exceeds maximum transport PDU size"},
	{534, "Illegal write or read only property"},
	{540, "Unexpected initial hook state"},
	{581, "Does Not Exist"},

	{600, "Illegal syntax within an announcement specification"},
	{601, "Variable type not supported"},
	{602, "Variable value out of range"},
	{603, "Category not supported"},
	{604, "Selector type not supported"},
	{605, "Selector value not supported"},
	{606, "Unknown segment ID"},
	{607, "Mismatch between play specification and provisioned data"},
	{608, "Provisioning error"},
	{609, "Invalid offset"},
	{610, "No free segment IDs"},
	{611, "Temporary segment not found"},
	{612, "Segment in use"},
	{613, "ISP port limit overrun"},
	{614, "No modems available"},
	{615, "Calling number unacceptable"},
	{616, "Called number unacceptable"},
	{  0, NULL }
};



static void
dissect_megaco_errordescriptor(tvbuff_t *tvb, proto_tree *megaco_tree_command_line,  gint tvb_RBRKT, gint tvb_previous_offset)
{

	gint 		tokenlen;
	gint		error_code;
	guint8	error[4];
	gint 		tvb_next_offset, tvb_current_offset,tvb_len;

	tvb_len			= tvb_length(tvb);
	tokenlen		= 0;
	tvb_next_offset		= 0;
	tvb_current_offset	= 0;
	tvb_len			= 0;


	tvb_current_offset = tvb_find_guint8(tvb, tvb_previous_offset , tvb_RBRKT, '=');
	tvb_current_offset = tvb_skip_wsp(tvb, tvb_current_offset +1);
	tvb_get_nstringz0(tvb,tvb_current_offset,4,error);
	error_code = atoi(error);
	proto_tree_add_string_hidden(megaco_tree_command_line, hf_megaco_error_descriptor, tvb,
					 		tvb_current_offset, 3,
							tvb_format_text(tvb, tvb_current_offset,
							3));

	tokenlen =  (tvb_RBRKT) - tvb_previous_offset+1;


	proto_tree_add_string(megaco_tree_command_line, hf_megaco_error_descriptor, tvb,
					 		tvb_previous_offset, tokenlen,
							tvb_format_text(tvb, tvb_previous_offset,
							tokenlen));

	proto_tree_add_text(megaco_tree_command_line, tvb, tvb_current_offset, 3,
	    "Error code: %s",
	    val_to_str(error_code, MEGACO_error_code_vals,
	      "Unknown (%u)"));

}
static void
dissect_megaco_TerminationStatedescriptor(tvbuff_t *tvb, proto_tree *megaco_mediadescriptor_tree,  gint tvb_next_offset, gint tvb_current_offset)
{
	gint tokenlen;
	gint tvb_offset, tvb_help_offset;
	guint8 tempchar;

	proto_tree  *megaco_TerminationState_tree, *megaco_TerminationState_ti;

	tokenlen		= 0;
	tvb_offset		= 0;
	tvb_help_offset = 0;

	tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_next_offset, '=');

	tokenlen = tvb_next_offset - tvb_current_offset;

	megaco_TerminationState_ti = proto_tree_add_item(megaco_mediadescriptor_tree,hf_megaco_TerminationState_descriptor,tvb,tvb_current_offset,tokenlen, FALSE);
	megaco_TerminationState_tree = proto_item_add_subtree(megaco_TerminationState_ti, ett_megaco_TerminationState);

	while ( tvb_offset < tvb_next_offset && tvb_offset != -1 ){

		tempchar = tvb_get_guint8(tvb, tvb_current_offset);
		tvb_help_offset = tvb_current_offset;

		tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);

		switch ( tempchar ){

		case 'S':
			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tempchar = tvb_get_guint8(tvb, tvb_current_offset);
			tokenlen = tvb_offset - tvb_current_offset;

			proto_tree_add_string(megaco_TerminationState_tree, hf_megaco_Service_State, tvb,
				tvb_current_offset, tokenlen,
				tvb_format_text(tvb, tvb_current_offset,
				tokenlen));

			break;

		case 'B':

			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tempchar = tvb_get_guint8(tvb, tvb_current_offset);
			tokenlen = tvb_offset - tvb_current_offset;

			proto_tree_add_string(megaco_TerminationState_tree, hf_megaco_Event_Buffer_Control, tvb,
				tvb_current_offset, tokenlen,
				tvb_format_text(tvb, tvb_current_offset,
				tokenlen));

			break;

		case 'E':
			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tempchar = tvb_get_guint8(tvb, tvb_current_offset);
			tokenlen = tvb_offset - tvb_current_offset;

			proto_tree_add_string(megaco_TerminationState_tree, hf_megaco_Event_Buffer_Control, tvb,
				tvb_current_offset, tokenlen,
				tvb_format_text(tvb, tvb_current_offset,
				tokenlen));

			break;

		default:
			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tempchar = tvb_get_guint8(tvb, tvb_help_offset);
			tokenlen = tvb_offset - tvb_help_offset;

			proto_tree_add_text(megaco_TerminationState_tree, tvb, tvb_help_offset, tokenlen,
				"%s", tvb_format_text(tvb,tvb_help_offset,
				tokenlen));
			break;
		}


		tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);
		tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_next_offset, '=');
	}
}

static void
dissect_megaco_Localdescriptor(tvbuff_t *tvb, proto_tree *megaco_mediadescriptor_tree,packet_info *pinfo, gint tvb_next_offset, gint tvb_current_offset)
{
	gint tokenlen;
	tvbuff_t *next_tvb;

	proto_tree  *megaco_localdescriptor_tree, *megaco_localdescriptor_ti;

	tokenlen = 0;

	tokenlen = tvb_next_offset - tvb_current_offset;



	megaco_localdescriptor_ti = proto_tree_add_item(megaco_mediadescriptor_tree,hf_megaco_Local_descriptor,tvb,tvb_current_offset,tokenlen, FALSE);
	megaco_localdescriptor_tree = proto_item_add_subtree(megaco_localdescriptor_ti, ett_megaco_Localdescriptor);

	tokenlen = tvb_next_offset - tvb_current_offset;
	if ( tokenlen > 3 ){
		next_tvb = tvb_new_subset(tvb, tvb_current_offset, tokenlen, tokenlen);
		call_dissector(sdp_handle, next_tvb, pinfo, megaco_localdescriptor_tree);
	}
}
static void
dissect_megaco_Remotedescriptor(tvbuff_t *tvb, proto_tree *megaco_mediadescriptor_tree,packet_info *pinfo, gint tvb_next_offset, gint tvb_current_offset)
{
	gint tokenlen;
	tvbuff_t *next_tvb;


	proto_tree  *megaco_Remotedescriptor_tree, *megaco_Remotedescriptor_ti;

	tokenlen = 0;

	tokenlen = tvb_next_offset - tvb_current_offset;

	megaco_Remotedescriptor_ti = proto_tree_add_item(megaco_mediadescriptor_tree,hf_megaco_Remote_descriptor,tvb,tvb_current_offset,tokenlen, FALSE);
	megaco_Remotedescriptor_tree = proto_item_add_subtree(megaco_Remotedescriptor_ti, ett_megaco_Remotedescriptor);

	if ( tokenlen > 3 ){
		next_tvb = tvb_new_subset(tvb, tvb_current_offset, tokenlen, tokenlen);
		call_dissector(sdp_handle, next_tvb, pinfo, megaco_Remotedescriptor_tree);
	}
}
static void
dissect_megaco_LocalControldescriptor(tvbuff_t *tvb, proto_tree *megaco_mediadescriptor_tree, packet_info *pinfo,  gint tvb_next_offset, gint tvb_current_offset)
{
	gint tokenlen;
	gint tvb_offset,tvb_help_offset;
	guint8 tempchar;


	proto_tree  *megaco_LocalControl_tree, *megaco_LocalControl_ti;

	tokenlen		= 0;
	tvb_offset		= 0;
	tvb_help_offset = 0;

	tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_next_offset, '=');

	tokenlen = tvb_next_offset - tvb_current_offset;

	megaco_LocalControl_ti = proto_tree_add_item(megaco_mediadescriptor_tree,hf_megaco_LocalControl_descriptor,tvb,tvb_current_offset,tokenlen, FALSE);
	megaco_LocalControl_tree = proto_item_add_subtree(megaco_LocalControl_ti, ett_megaco_LocalControldescriptor);

	while ( tvb_offset < tvb_next_offset && tvb_offset != -1 ){

		tempchar = tvb_get_guint8(tvb, tvb_current_offset);
		tvb_help_offset	= tvb_current_offset;
		tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);


		switch ( tempchar ){

		case 'M':
			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tokenlen = tvb_offset - tvb_current_offset;

			proto_tree_add_string(megaco_LocalControl_tree, hf_megaco_mode, tvb,
				tvb_current_offset, tokenlen,
				tvb_format_text(tvb, tvb_current_offset,
				tokenlen));
			if (check_col(pinfo->cinfo, COL_INFO) )
				col_append_fstr(pinfo->cinfo, COL_INFO, " (Mode:%s)",tvb_format_text(tvb, tvb_current_offset,tokenlen));
			tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);
			break;

		case 'R':
			if ( tvb_get_guint8(tvb, tvb_help_offset+1) == 'V' || tvb_get_guint8(tvb, tvb_help_offset+8)  == 'V'){

				tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
				if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
					tvb_offset = tvb_next_offset;
				}

				tokenlen = tvb_offset - tvb_current_offset;

				proto_tree_add_string(megaco_LocalControl_tree, hf_megaco_reserve_value, tvb,
					tvb_current_offset, tokenlen,
					tvb_format_text(tvb, tvb_current_offset,
					tokenlen));

				tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);
			}
			else {
				tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
				if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
					tvb_offset = tvb_next_offset;
				}

				tokenlen = tvb_offset - tvb_current_offset;

				proto_tree_add_string(megaco_LocalControl_tree, hf_megaco_reserve_group, tvb,
					tvb_current_offset, tokenlen,
					tvb_format_text(tvb, tvb_current_offset,
					tokenlen));
				tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);
			}
			break;

		default:
			tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_offset, ',');
			if ( tvb_offset == -1 || tvb_offset > tvb_next_offset ){
				tvb_offset = tvb_next_offset;
			}

			tokenlen = tvb_offset - tvb_help_offset;

			proto_tree_add_text(megaco_LocalControl_tree, tvb, tvb_help_offset, tokenlen,
				"%s", tvb_format_text(tvb,tvb_help_offset,
				tokenlen));
			tvb_current_offset = tvb_skip_wsp(tvb, tvb_offset +1);

			break;
		}
		tvb_offset = tvb_find_guint8(tvb, tvb_current_offset , tvb_next_offset, '=');
	}
}
/* Copied from MGCP dissector, prints whole message in raw text */

static void tvb_raw_text_add(tvbuff_t *tvb, proto_tree *tree){

  gint tvb_linebegin,tvb_lineend,tvb_len,linelen;

  tvb_linebegin = 0;
  tvb_len = tvb_length(tvb);

  proto_tree_add_text(tree, tvb, 0, -1,"-------------- (RAW text output) ---------------");

  do {
    linelen = tvb_find_line_end(tvb,tvb_linebegin,-1,&tvb_lineend,FALSE);
    proto_tree_add_text(tree, tvb, tvb_linebegin, linelen,
			"%s", tvb_format_text(tvb,tvb_linebegin,
					      linelen));
    tvb_linebegin = tvb_lineend;
  } while ( tvb_lineend < tvb_len );
}

/* Register all the bits needed with the filtering engine */

void
proto_register_megaco(void)
{
	static hf_register_info hf[] = {
		{ &hf_megaco_audit_descriptor,
		{ "Audit Descriptor", "megaco.audit", FT_STRING, BASE_DEC, NULL, 0x0,
		"Audit Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_command_line,
		{ "Command line", "megaco.command_line", FT_STRING, BASE_DEC, NULL, 0x0,
		"Commands of this message ", HFILL }},
		{ &hf_megaco_command,
		{ "Command", "megaco.command", FT_STRING, BASE_DEC, NULL, 0x0,
		"Command of this message ", HFILL }},
		{ &hf_megaco_Context,
		{ "Context", "megaco.context", FT_STRING, BASE_DEC, NULL, 0x0,
		"Context ID of this massage ", HFILL }},
		{ &hf_megaco_digitmap_descriptor,
		{ "DigitMap Descriptor", "megaco.digitmap", FT_STRING, BASE_DEC, NULL, 0x0,
		"DigitMap Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_error_descriptor,
		{ "ERROR Descriptor", "megaco.error", FT_STRING, BASE_DEC, NULL, 0x0,
		"Error Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_error_Frame,
		{ "ERROR frame", "megaco.error_frame", FT_STRING, BASE_DEC, NULL, 0x0,
		"Syntax error ", HFILL }},
		{ &hf_megaco_Event_Buffer_Control,
		{ "Event Buffer Control", "megaco.eventbuffercontrol", FT_STRING, BASE_DEC, NULL, 0x0,
		"Event Buffer Control in Termination State Descriptor", HFILL }},
		{ &hf_megaco_events_descriptor,
		{ "Events Descriptor", "megaco.events", FT_STRING, BASE_DEC, NULL, 0x0,
		"Events Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_Local_descriptor,
		{ "Local Descriptor", "megaco.localdescriptor", FT_STRING, BASE_DEC, NULL, 0x0,
		"Local Descriptor in Media Descriptor ", HFILL }},
		{ &hf_megaco_LocalControl_descriptor,
		{ "Local Control Descriptor", "megaco.localcontroldescriptor", FT_STRING, BASE_DEC, NULL, 0x0,
		"Local Control Descriptor in Media Descriptor ", HFILL }},
		{ &hf_megaco_media_descriptor,
		{ "Media Descriptor", "megaco.media", FT_STRING, BASE_DEC, NULL, 0x0,
		"Media Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_modem_descriptor,
		{ "Modem Descriptor", "megaco.modem", FT_STRING, BASE_DEC, NULL, 0x0,
		"Modem Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_mode,
		{ "Mode", "megaco.mode", FT_STRING, BASE_DEC, NULL, 0x0,
		"Mode  sendonly/receiveonly/inactive/loopback", HFILL }},
		{ &hf_megaco_multiplex_descriptor,
		{ "Multiplex Descriptor", "megaco.multiplex", FT_STRING, BASE_DEC, NULL, 0x0,
		"Multiplex Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_observedevents_descriptor,
		{ "Observed Events Descriptor", "megaco.observedevents", FT_STRING, BASE_DEC, NULL, 0x0,
		"Observed Events Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_packages_descriptor,
		{ "Packages Descriptor", "megaco.packagesdescriptor", FT_STRING, BASE_DEC, NULL, 0x0,
		"Packages Descriptor", HFILL }},
		{ &hf_megaco_pkgdname,
		{ "pkgdName", "megaco.pkgdname", FT_STRING, BASE_DEC, NULL, 0x0,
		"PackageName SLASH ItemID", HFILL }},
		{ &hf_megaco_Remote_descriptor,
		{ "Remote Descriptor", "megaco.remotedescriptor", FT_STRING, BASE_DEC, NULL, 0x0,
		"Remote Descriptor in Media Descriptor ", HFILL }},
		{ &hf_megaco_reserve_group,
		{ "Reserve Group", "megaco.reservegroup", FT_STRING, BASE_DEC, NULL, 0x0,
		"Reserve Group on or off", HFILL }},
		{ &hf_megaco_reserve_value,
		{ "Reserve Value", "megaco.reservevalue", FT_STRING, BASE_DEC, NULL, 0x0,
		"Reserve Value on or off", HFILL }},
		{ &hf_megaco_requestid,
		{ "RequestID", "megaco.requestid", FT_STRING, BASE_DEC, NULL, 0x0,
		"RequestID in Events or Observedevents Descriptor ", HFILL }},
		{ &hf_megaco_servicechange_descriptor,
		{ "Service Change Descriptor", "megaco.servicechange", FT_STRING, BASE_DEC, NULL, 0x0,
		"Service Change Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_Service_State,
		{ "Service State", "megaco.servicestates", FT_STRING, BASE_DEC, NULL, 0x0,
		"Service States in Termination State Descriptor", HFILL }},
		{ &hf_megaco_signal_descriptor,
		{ "Signal Descriptor", "megaco.signal", FT_STRING, BASE_DEC, NULL, 0x0,
		"Signal Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_statistics_descriptor,
		{ "Statistics Descriptor", "megaco.statistics", FT_STRING, BASE_DEC, NULL, 0x0,
		"Statistics Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_streamid,
		{ "StreamID", "megaco.streamid", FT_STRING, BASE_DEC, NULL, 0x0,
		"StreamID in the Media Descriptor ", HFILL }},
		{ &hf_megaco_termid,
		{ "Termination ID", "megaco.termid", FT_STRING, BASE_DEC, NULL, 0x0,
		"Termination ID of this Command ", HFILL }},
		{ &hf_megaco_TerminationState_descriptor,
		{ "Termination State Descriptor", "megaco.terminationstate", FT_STRING, BASE_DEC, NULL, 0x0,
		"Termination State Descriptor in Media Descriptor ", HFILL }},
		{ &hf_megaco_topology_descriptor,
		{ "Topology Descriptor", "megaco.topology", FT_STRING, BASE_DEC, NULL, 0x0,
		"Topology Descriptor of the megaco Command ", HFILL }},
		{ &hf_megaco_transaction,
		{ "Transaction", "megaco.transaction", FT_STRING, BASE_DEC, NULL, 0x0,
		"Message Originator", HFILL }},
		{ &hf_megaco_transid,
		{ "Transaction ID", "megaco.transid", FT_STRING, BASE_DEC, NULL, 0x0,
		"Transaction ID of this message", HFILL }},
		{ &hf_megaco_mId,
		{ "MediagatewayID", "megaco.mId", FT_STRING, BASE_DEC, NULL, 0x0,
		"Mediagateway ID", HFILL }},
		{ &hf_megaco_version,
		{ "Version", "megaco.version", FT_STRING, BASE_DEC, NULL, 0x0,
		"Version", HFILL }},
		{ &hf_megaco_h245,
		{ "h245", "megaco.h245", FT_STRING, BASE_DEC, NULL, 0x0,
		"Embedded H.245 message", HFILL }},

		/* Add more fields here */
	};
	static gint *ett[] = {
		&ett_megaco,
			&ett_megaco_command_line,
			&ett_megaco_descriptors,
			&ett_megaco_mediadescriptor,
			&ett_megaco_TerminationState,
			&ett_megaco_Remotedescriptor,
			&ett_megaco_Localdescriptor,
			&ett_megaco_LocalControldescriptor,
			&ett_megaco_auditdescriptor,
			&ett_megaco_eventsdescriptor,
			&ett_megaco_observedeventsdescriptor,
			&ett_megaco_observedevent,
			&ett_megaco_packagesdescriptor,
			&ett_megaco_requestedevent,
			&ett_megaco_signalsdescriptor,
			&ett_megaco_requestedsignal,
			&ett_megaco_h245,
	};
	module_t *megaco_module;

	proto_megaco = proto_register_protocol("MEGACO",
					   "MEGACO", "megaco");

	register_dissector("megaco", dissect_megaco_text, proto_megaco);

	proto_register_field_array(proto_megaco, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));

	/* Register our configuration options, particularly our ports */

	megaco_module = prefs_register_protocol(proto_megaco, proto_reg_handoff_megaco);

	prefs_register_uint_preference(megaco_module, "tcp.txt_port",
		"MEGACO Text TCP Port",
		"Set the TCP port for MEGACO text messages",
		10, &global_megaco_txt_tcp_port);

	prefs_register_uint_preference(megaco_module, "udp.txt_port",
		"MEGACO Text UDP Port",
		"Set the UDP port for MEGACO text messages",
		10, &global_megaco_txt_udp_port);

#if 0
	prefs_register_uint_preference(megaco_module, "tcp.bin_port",
		"MEGACO Binary TCP Port",
		"Set the TCP port for MEGACO binary messages",
		10, &global_megaco_bin_tcp_port);

	prefs_register_uint_preference(megaco_module, "udp.bin_port",
		"MEGACO Binary UDP Port",
		"Set the UDP port for MEGACO binary messages",
		10, &global_megaco_bin_udp_port);
#endif

	prefs_register_bool_preference(megaco_module, "display_raw_text",
		"Display raw text for MEGACO message",
		"Specifies that the raw text of the "
		"MEGACO message should be displayed "
		"instead of (or in addition to) the "
		"dissection tree",
		&global_megaco_raw_text);

	prefs_register_bool_preference(megaco_module, "display_dissect_tree",
		"Display tree dissection for MEGACO message",
		"Specifies that the dissection tree of the "
		"MEGACO message should be displayed "
		"instead of (or in addition to) the "
		"raw text",
		&global_megaco_dissect_tree);
}




/* The registration hand-off routine */
void
proto_reg_handoff_megaco(void)
{
	static int megaco_prefs_initialized = FALSE;
	static dissector_handle_t megaco_text_tcp_handle;

	sdp_handle = find_dissector("sdp");
	h245_handle = find_dissector("h245dg");

	if (!megaco_prefs_initialized) {
		megaco_text_handle = create_dissector_handle(dissect_megaco_text,
			proto_megaco);
		megaco_text_tcp_handle = create_dissector_handle(dissect_megaco_text_tcp,
			proto_megaco);

		megaco_prefs_initialized = TRUE;
	}
	else {
		dissector_delete("tcp.port", txt_tcp_port, megaco_text_tcp_handle);
		dissector_delete("udp.port", txt_udp_port, megaco_text_handle);
#if 0
		dissector_delete("tcp.port", bin_tcp_port, megaco_text_tcp_handle);
		dissector_delete("udp.port", bin_udp_port, megaco_bin_handle);
#endif
	}

	/* Set our port number for future use */

	txt_tcp_port = global_megaco_txt_tcp_port;
	txt_udp_port = global_megaco_txt_udp_port;

#if 0
	bin_tcp_port = global_megaco_bin_tcp_port;
	bin_udp_port = global_megaco_bin_udp_port;
#endif

	dissector_add("tcp.port", global_megaco_txt_tcp_port, megaco_text_tcp_handle);
	dissector_add("udp.port", global_megaco_txt_udp_port, megaco_text_handle);
#if 0
	dissector_add("tcp.port", global_megaco_bin_tcp_port, megaco_bin_handle);
	dissector_add("udp.port", global_megaco_bin_udp_port, megaco_bin_handle);
#endif
	/* XXX - text or binary?  Does that depend on the port number? */
	dissector_add("sctp.ppi", H248_PAYLOAD_PROTOCOL_ID,   megaco_text_handle);

}

/*
* tvb_skip_wsp - Returns the position in tvb of the first non-whitespace
*		 character following offset or offset + maxlength -1 whichever
*		 is smaller.
*
* Parameters:
* tvb - The tvbuff in which we are skipping whitespaces, tab and end_of_line characters.
* offset - The offset in tvb from which we begin trying to skip whitespace.
*
* Returns: The position in tvb of the first non-whitespace
*/
static gint tvb_skip_wsp(tvbuff_t* tvb, gint offset ){
	gint counter = offset;
	gint end,tvb_len;
	guint8 tempchar;
	tvb_len = tvb_length(tvb);
	end = tvb_len;

	for(counter = offset; counter < end &&
		((tempchar = tvb_get_guint8(tvb,counter)) == ' ' ||
		tempchar == '\t' || tempchar == '\n' || tempchar == '\r'); counter++);
	return (counter);
}
static gint tvb_skip_wsp_return(tvbuff_t* tvb, gint offset){
	gint counter = offset;
	gint end;
	guint8 tempchar;
	end = 0;

	for(counter = offset; counter > end &&
		((tempchar = tvb_get_guint8(tvb,counter)) == ' ' ||
		tempchar == '\t' || tempchar == '\n' || tempchar == '\r'); counter--);
	counter++;
	return (counter);
}


/* Start the functions we need for the plugin stuff */

#ifndef ENABLE_STATIC

G_MODULE_EXPORT void
plugin_register(void)
{
	/* register the new protocol, protocol fields, and subtrees */
	if (proto_megaco == -1) { /* execute protocol initialization only once */
		proto_register_megaco();
	}
}

G_MODULE_EXPORT void
plugin_reg_handoff(void){
	proto_reg_handoff_megaco();
}

#endif

/* End the functions we need for plugin stuff */