{ &hf_mgcp_param_connectionid,      {"ConnectionIdentifier (I)", "mgcp.param.connectionid", FT_STRING,        BASE_DEC, NULL, 0x0, "Connection Identifier", HFILL }},    { &hf_mgcp_param_secondconnectionid,      { "SecondConnectionID (I2)", "mgcp.param.secondconnectionid", FT_STRING,        BASE_DEC, NULL, 0x0, "Second Connection Identifier", HFILL }},    { &hf_mgcp_param_notifiedentity,      { "NotifiedEntity (N)", "mgcp.param.notifiedentity", FT_STRING, BASE_DEC,	NULL, 0x0, "Notified Entity", HFILL }},    { &hf_mgcp_param_requestid,      { "RequestIdentifier (X)", "mgcp.param.requestid", FT_STRING, BASE_DEC,	NULL, 0x0, "Request Identifier", HFILL }},    { &hf_mgcp_param_localconnoptions,      { "LocalConnectionOptions (L)", "mgcp.param.localconnectionoptions", 	FT_STRING, BASE_DEC, NULL, 0x0, "Local Connection Options", HFILL }},    { &hf_mgcp_param_connectionmode,      { "ConnectionMode (M)", "mgcp.param.connectionmode", FT_STRING, BASE_DEC,	NULL, 0x0, "Connection Mode", HFILL }},    { &hf_mgcp_param_reqevents,      { "RequestedEvents (R)", "mgcp.param.reqevents", FT_STRING, BASE_DEC,	NULL, 0x0, "Requested Events", HFILL }},    { &hf_mgcp_param_signalreq,      { "SignalRequests (S)", "mgcp.param.signalreq", FT_STRING, BASE_DEC,	NULL, 0x0, "Signal Request", HFILL }},    { &hf_mgcp_param_restartmethod,       { "RestartMethod (RM)", "mgcp.param.restartmethod", FT_STRING, BASE_DEC,	NULL, 0x0, "Restart Method", HFILL }},    { &hf_mgcp_param_restartdelay,      { "RestartDelay (RD)", "mgcp.param.restartdelay", FT_STRING, BASE_DEC,	NULL, 0x0, "Restart Delay", HFILL }},    { &hf_mgcp_param_digitmap,       { "DigitMap (D)", "mgcp.param.digitmap", FT_STRING, BASE_DEC, NULL, 0x0,	"Digit Map", HFILL }},    { &hf_mgcp_param_observedevent,       { "ObservedEvents (O)", "mgcp.param.observedevents", FT_STRING, 	BASE_DEC, NULL, 0x0, "Observed Events", HFILL }},    { &hf_mgcp_param_connectionparam,      { "ConnectionParameters (P)", "mgcp.param.connectionparam", FT_STRING, 	BASE_DEC, NULL, 0x0, "Connection Parameters", HFILL }},    { &hf_mgcp_param_reasoncode,      { "ReasonCode (E)", "mgcp.param.reasoncode", FT_STRING, BASE_DEC,	NULL, 0x0, "Reason Code", HFILL }},    { &hf_mgcp_param_eventstates,      { "EventStates (ES)", "mgcp.param.eventstates", FT_STRING, BASE_DEC,	NULL, 0x0, "Event States", HFILL }},    { &hf_mgcp_param_specificendpoint,      { "SpecificEndpointID (Z)", "mgcp.param.specificendpointid", FT_STRING,	BASE_DEC, NULL, 0x0, "Specific Endpoint ID", HFILL }},    { &hf_mgcp_param_secondendpointid,      { "SecondEndpointID (Z2)", "mgcp.param.secondendpointid", FT_STRING,	BASE_DEC, NULL, 0x0, "Second Endpoing ID", HFILL }},    { &hf_mgcp_param_reqinfo,      { "RequestedInfo (F)", "mgcp.param.reqinfo", FT_STRING, BASE_DEC, 	NULL, 0x0,"Requested Info", HFILL }},    { &hf_mgcp_param_quarantinehandling,       { "QuarantineHandling (Q)", "mgcp.param.quarantinehandling", FT_STRING,	BASE_DEC, NULL, 0x0, "Quarantine Handling", HFILL }},    { &hf_mgcp_param_detectedevents,      { "DetectedEvents (T)", "mgcp.param.detectedevents", FT_STRING, BASE_DEC,	NULL, 0x0, "Detected Events", HFILL }},    { &hf_mgcp_param_capabilities,      { "Capabilities (A)", "mgcp.param.capabilities", FT_STRING, BASE_DEC,	NULL, 0x0, "Capabilities", HFILL }},    { &hf_mgcp_param_extention,      { "Extention Parameter (X-*)", "mgcp.param.extention", FT_STRING, 	BASE_DEC, NULL, 0x0, "Extension Parameter", HFILL }},    { &hf_mgcp_param_invalid,      { "Invalid Parameter", "mgcp.param.invalid", FT_STRING, 	BASE_DEC, NULL, 0x0, "Invalid Parameter", HFILL }},    { &hf_mgcp_messagecount,       { "MGCP Message Count", "mgcp.messagecount", FT_UINT32, 	BASE_DEC, NULL, 0x0, "Number of MGCP message in a packet", HFILL }},    /* Add more fields here */  };  static gint *ett[] = {    &ett_mgcp,    &ett_mgcp_param,  };  module_t *mgcp_module;   proto_mgcp = proto_register_protocol("Media Gateway Control Protocol",				       "MGCP", "mgcp");  proto_register_field_array(proto_mgcp, hf, array_length(hf));  proto_register_subtree_array(ett, array_length(ett));  /* Register our configuration options for , particularly our ports */  mgcp_module = prefs_register_protocol(proto_mgcp, proto_reg_handoff_mgcp);  prefs_register_uint_preference(mgcp_module, "tcp.gateway_port", 				 "MGCP Gateway TCP Port",				 "Set the UDP port for gateway messages "				 "(if other than the default of 2427)",				 10, &global_mgcp_gateway_tcp_port);  prefs_register_uint_preference(mgcp_module, "udp.gateway_port", 				 "MGCP Gateway UDP Port",				 "Set the TCP port for gateway messages "				 "(if other than the default of 2427)",				 10, &global_mgcp_gateway_udp_port);  prefs_register_uint_preference(mgcp_module, "tcp.callagent_port", 				 "MGCP Callagent TCP Port",				 "Set the TCP port for callagent messages "				 "(if other than the default of 2727)",				 10, &global_mgcp_callagent_tcp_port);  prefs_register_uint_preference(mgcp_module, "udp.callagent_port", 				 "MGCP Callagent UDP Port",				 "Set the UDP port for callagent messages "				 "(if other than the default of 2727)",				 10, &global_mgcp_callagent_udp_port);  prefs_register_bool_preference(mgcp_module, "display_raw_text",                                  "Display raw text for MGCP message",                                  "Specifies that the raw text of the "                                 "MGCP message should be displayed "				 "instead of (or in addition to) the "				 "dissection tree",                                 &global_mgcp_raw_text);  prefs_register_bool_preference(mgcp_module, "display_dissect_tree",                                  "Display tree dissection for MGCP message",                                  "Specifies that the dissection tree of the "                                 "MGCP message should be displayed "				 "instead of (or in addition to) the "				 "raw text",                                 &global_mgcp_dissect_tree);  prefs_register_bool_preference(mgcp_module, "display_mgcp_message_count",                                  "Display the number of MGCP messages",                                  "Display the number of MGCP messages "                                 "found in a packet in the protocol column.",                                 &global_mgcp_message_count);}/* The registration hand-off routine */voidproto_reg_handoff_mgcp(void){  static int mgcp_prefs_initialized = FALSE;  static dissector_handle_t mgcp_handle;  /*   * Get a handle for the SDP dissector.   */  sdp_handle = find_dissector("sdp");  if (!mgcp_prefs_initialized) {    mgcp_handle = create_dissector_handle(dissect_mgcp, proto_mgcp);    mgcp_prefs_initialized = TRUE;  }  else {    dissector_delete("tcp.port", gateway_tcp_port, mgcp_handle);    dissector_delete("udp.port", gateway_udp_port, mgcp_handle);    dissector_delete("tcp.port", callagent_tcp_port, mgcp_handle);    dissector_delete("udp.port", callagent_udp_port, mgcp_handle);  }  /* Set our port number for future use */  gateway_tcp_port = global_mgcp_gateway_tcp_port;  gateway_udp_port = global_mgcp_gateway_udp_port;  callagent_tcp_port = global_mgcp_callagent_tcp_port;  callagent_udp_port = global_mgcp_callagent_udp_port;  dissector_add("tcp.port", global_mgcp_gateway_tcp_port, mgcp_handle);  dissector_add("udp.port", global_mgcp_gateway_udp_port, mgcp_handle);  dissector_add("tcp.port", global_mgcp_callagent_tcp_port, mgcp_handle);  dissector_add("udp.port", global_mgcp_callagent_udp_port, mgcp_handle);}/*  * is_mgcp_verb - A function for determining whether there is a  *                MGCP verb at offset in tvb * * Parameter: * tvb - The tvbuff in which we are looking for an MGCP verb * offset - The offset in tvb at which we are looking for a MGCP verb * maxlength - The maximum distance from offset we may look for the  *             characters that make up a MGCP verb.   * * Return: TRUE if there is an MGCP verb at offset in tvb, otherwise FALSE */static gboolean is_mgcp_verb(tvbuff_t *tvb, gint offset, gint maxlength){  int returnvalue = FALSE;  guint8 word[5];  if(( maxlength >= 4) && tvb_get_nstringz0(tvb,offset,4,word)){    if (strncasecmp(word, "EPCF", 4) == 0 ||	strncasecmp(word, "CRCX", 4) == 0 ||	strncasecmp(word, "MDCX", 4) == 0 ||	strncasecmp(word, "DLCX", 4) == 0 ||	strncasecmp(word, "RQNT", 4) == 0 ||	strncasecmp(word, "NTFY", 4) == 0 ||	strncasecmp(word, "AUEP", 4) == 0 ||	strncasecmp(word, "AUCX", 4) == 0 ||	strncasecmp(word, "RSIP", 4) == 0 ||	(word[0] == 'X' && is_rfc2234_alpha(word[1]) && is_rfc2234_alpha(word[2]) &&	 is_rfc2234_alpha(word[3]))	){      returnvalue = TRUE;    }  }  if( returnvalue && maxlength >= 5 &&       (word[0] = tvb_get_guint8(tvb,4)) != ' ' && word[0] != '\t'){    returnvalue = FALSE;  }  return returnvalue;}/* * is_mgcp_rspcode - A function for determining whether something which  *                   looks roughly like a MGCP response code is at  *                   offset in tvb * * Parameters: * tvb - The tvbuff in which we are looking for an MGCP response code * offset - The offset in tvb at which we are looking for a MGCP response code * maxlength - The maximum distance from offset we may look for the  *             characters that make up a MGCP response code.   * * Return: TRUE if there is an MGCP response code at offset in tvb,  *         otherwise FALSE */static gboolean is_mgcp_rspcode(tvbuff_t *tvb, gint offset, gint maxlength){  int returnvalue = FALSE;  guint8 word[4];  if(maxlength >= 3){      tvb_get_nstringz0(tvb,offset,3,word);    if( isdigit(word[0]) &&	isdigit(word[1]) &&	isdigit(word[2])){       returnvalue = TRUE;    }  }  if( returnvalue && maxlength >= 4 &&       (word[0] = tvb_get_guint8(tvb,3)) != ' ' && word[0] != '\t'){    returnvalue = FALSE;  }  return returnvalue;}/* * is_rfc2234_alpha - Indicates whether the character c is an alphabetical  *                    character.  This function is used instead of  *                    isalpha because isalpha may deviate from the rfc2234 *                    definition of ALPHA in some locales. *  * Parameter: * c - The character being checked for being an alphabetical character. * * Return: TRUE if c is an upper or lower case alphabetical character, *         FALSE otherwise. */static gboolean is_rfc2234_alpha(guint8 c){  int returnvalue = FALSE;  if(( c <= 'Z' && c >= 'A' ) || (c <= 'z' && c >= 'a')){    returnvalue = TRUE;  }  return returnvalue;}  /* * tvb_parse_param - Parse the MGCP param into a type and a value. * * Parameters: * tvb - The tvbuff containing the MGCP param we are to parse. * offset - The offset in tvb at which we will begin looking for a  *          MGCP parameter to parse. * len - The maximum distance from offset in tvb that we can look for *       an MGCP parameter to parse. * hf - The place to write a pointer to the integer representing the  *      header field associated with the MGCP parameter parsed. * * Returns: The offset in tvb where the value of the MGCP parameter  *          begins. */static gint tvb_parse_param(tvbuff_t* tvb, gint offset, gint len, int** hf){  gint returnvalue, tvb_current_offset,counter;  guint8 tempchar;  tvb_current_offset = offset;  returnvalue = -1;  *hf = NULL;  if(len > 0){    tempchar = tvb_get_guint8(tvb,tvb_current_offset);    switch(tempchar){    case 'K':      *hf = &hf_mgcp_param_rspack;      break;    case 'B':      *hf = &hf_mgcp_param_bearerinfo;      break;    case 'C':      *hf = &hf_mgcp_param_callid;      break;    case 'I':      tvb_current_offset++;      if(len > (tvb_current_offset - offset) && 	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){ 	*hf = &hf_mgcp_param_connectionid;	tvb_current_offset--;      }      else if ( tempchar == '2'){	*hf = &hf_mgcp_param_secondconnectionid;      }      break;    case 'N':      *hf = &hf_mgcp_param_notifiedentity;      break;    case 'X':      tvb_current_offset++;      if(len > (tvb_current_offset - offset) && 	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){	*hf = &hf_mgcp_param_requestid;      }      else if(len > (tvb_current_offset - offset) && (	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == '-' || 	 tempchar == '+')){	tvb_current_offset++;	for(counter = 1;(counter <= 6) && (len > (counter + tvb_current_offset						  - offset))	      && ( is_rfc2234_alpha(tempchar = 				    tvb_get_guint8(tvb,						   tvb_current_offset+counter))		   || isdigit(tempchar));counter++);	if(tempchar == ':'){	  tvb_current_offset += counter;	  *hf = &hf_mgcp_param_extention;	}      }       tvb_current_offset--;      break;    case 'L':      *hf = &hf_mgcp_param_localconnoptions;      break;    case 'M':      *hf = &hf_mgcp_param_connectionmode;      break;    case 'R':      tvb_current_offset++;      if(len > (tvb_current_offset - offset) && 	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){ 	*hf = &hf_mgcp_param_reqevents;	tvb_current_offset--;      }      else if ( tempchar == 'M'){	*hf = &hf_mgcp_param_restartmethod;      }      else if ( tempchar == 'D'){	*hf = &hf_mgcp_param_restartdelay;      }      break;    case 'S':      *hf = &hf_mgcp_param_signalreq;      break;    case 'D':      *hf = &hf_mgcp_param_digitmap;      break;    case 'O':      *hf = &hf_mgcp_param_observedevent;      break;    case 'P':      *hf = &hf_mgcp_param_connectionparam;      break;    case 'E':      tvb_current_offset++;      if(len > (tvb_current_offset - offset) && 	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){ 	*hf = &hf_mgcp_param_reasoncode;	tvb_current_offset--;      }      else if ( tempchar == 'S'){	*hf = &hf_mgcp_param_eventstates;      }      break;    case 'Z':      tvb_current_offset++;      if(len > (tvb_current_offset - offset) && 	 (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){ 	*hf = &hf_mgcp_param_specificendpoint;	tvb_current_offset--;      }      else if ( tempchar == '2'){	*hf = &hf_mgcp_param_secondendpointid;      }      break;    case 'F':      *hf = &hf_mgcp_param_reqinfo;      break;    case 'Q':      *hf = &hf_mgcp_param_quarantinehandling;      break;    case 'T':      *hf = &hf_mgcp_param_detectedevents;      break;    case 'A':      *hf = &hf_mgcp_param_capabilities;      break;    default:      *hf = &hf_mgcp_param_invalid;      break;    }        tvb_current_offset++;    if(*hf != NULL && len > (tvb_current_offset - offset) &&        (tempchar = tvb_get_guint8(tvb,tvb_current_offset)) == ':'){      tvb_current_offset++;      tvb_current_offset = tvb_skip_wsp(tvb,tvb_current_offset,					(len - tvb_current_offset + offset));      returnvalue = tvb_current_offset;    }    else {      *hf = &hf_mgcp_param_invalid;    }  }