doubango/tinySIP/src/dialogs/tsip_dialog_layer.c
c732d49e
 #if HAVE_CRT
 #define _CRTDBG_MAP_ALLOC 
 #include <stdlib.h> 
 #include <crtdbg.h>
 #endif //HAVE_CRT
 /*
 * Copyright (C) 2017, University of the Basque Country (UPV/EHU)
 * Contact for licensing options: <licensing-mcpttclient(at)mcopenplatform(dot)com>
 *
 * The original file was part of Open Source Doubango Framework
 * Copyright (C) 2010-2011 Mamadou Diop.
 * Copyright (C) 2012 Doubango Telecom <http://doubango.org>
 *
 * This file is part of Open Source Doubango Framework.
 *
 * DOUBANGO 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 3 of the License, or
 * (at your option) any later version.
 *
 * DOUBANGO 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 DOUBANGO.
 *
 */
 
 
 /**@file tsip_dialog_layer.c
  * @brief SIP dialog layer.
  *
  * @author Mamadou Diop <diopmamadou(at)doubango[dot]org>
  *
 
  */
 #include "tinysip/dialogs/tsip_dialog_layer.h"
 
 #include "tinysip/dialogs/tsip_dialog_invite.h"
 #include "tinysip/dialogs/tsip_dialog_message.h"
 #include "tinysip/dialogs/tsip_dialog_info.h"
 #include "tinysip/dialogs/tsip_dialog_options.h"
 #include "tinysip/dialogs/tsip_dialog_publish.h"
 #include "tinysip/dialogs/tsip_dialog_register.h"
 #include "tinysip/dialogs/tsip_dialog_subscribe.h"
 
 #include "tinysip/transactions/tsip_transac_layer.h"
 #include "tinysip/transports/tsip_transport_layer.h"
 
 #include "tsk_debug.h"
 
 extern tsip_ssession_handle_t *tsip_ssession_create_2(const tsip_stack_t* stack, const struct tsip_message_s* message);
 
 /*== Predicate function to find dialog by type */
 static int pred_find_dialog_by_type(const tsk_list_item_t *item, const void *type)
 {
 	if(item && item->data){
 		tsip_dialog_t *dialog = item->data;
 		return (dialog->type - *((tsip_dialog_type_t*)type));
 	}
 	return -1;
 }
 
 /*== Predicate function to find dialog by not type */
 static int pred_find_dialog_by_not_type(const tsk_list_item_t *item, const void *type)
 {
 	if(item && item->data){
 		tsip_dialog_t *dialog = item->data;
 		if(dialog->type != *((tsip_dialog_type_t*)type)){
 			return 0;
 		}
 	}
 	return -1;
 }
 
 /*== Predicate function to find dialog by callid */
 static int pred_find_dialog_by_callid(const tsk_list_item_t *item, const void *callid)
 {
 	if(item && item->data && callid){
 		return tsk_strcmp(((tsip_dialog_t*)item->data)->callid, ((const char*)callid));
 	}
 	return -1;
 }
 
 tsip_dialog_layer_t* tsip_dialog_layer_create(tsip_stack_t* stack)
 {
 	return tsk_object_new(tsip_dialog_layer_def_t, stack);
 }
 
 // it's up to the caller to release the returned object
 tsip_dialog_t* tsip_dialog_layer_find_by_ss(tsip_dialog_layer_t *self, const tsip_ssession_handle_t *ss)
 {
 	return tsip_dialog_layer_find_by_ssid(self, tsip_ssession_get_id(ss));
 }
 
 // it's up to the caller to release the returned object
 tsip_dialog_t* tsip_dialog_layer_find_by_ssid(tsip_dialog_layer_t *self, tsip_ssession_id_t ssid)
 {
 	tsip_dialog_t *ret = 0;
 	tsip_dialog_t *dialog;
 	tsk_list_item_t *item;
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 	TSK_DEBUG_INFO("tsip_dialog_layer_find_by_ssid");
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 	tsk_safeobj_lock(self);
 
 	tsk_list_foreach(item, self->dialogs){
 		dialog = item->data;
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 		if(tsip_ssession_get_id(dialog->ss) == ssid){
 			ret = dialog;
 			break;
 		}
 	}
 
 	tsk_safeobj_unlock(self);
 
 	return tsk_object_ref(ret);
 }
 
 // it's up to the caller to release the returned object
 tsip_dialog_t* tsip_dialog_layer_find_by_callid(tsip_dialog_layer_t *self, const char* callid)
 {
 	if(!self || !callid){
 		TSK_DEBUG_ERROR("Invalid parameter");
 		return tsk_null;
 	}
 	else{
 		tsip_dialog_t *dialog = tsk_null;
 		tsk_list_item_t *item;
 		//--tsk_safeobj_lock(self);
 		tsk_list_foreach(item, self->dialogs){
 			if(tsk_striequals(TSIP_DIALOG(item->data)->callid, callid)){
 				dialog = tsk_object_ref(item->data);
 				break;
 			}
 		}
 		//--tsk_safeobj_unlock(self);
 		return dialog;
 	}
 }
 
 tsk_bool_t tsip_dialog_layer_have_dialog_with_callid(const tsip_dialog_layer_t *self, const char* callid)
 {
 	tsk_bool_t found = tsk_false;
 	if(self){
 		tsk_safeobj_lock(self);
 		if(tsk_list_find_item_by_pred(self->dialogs, pred_find_dialog_by_callid, callid) != tsk_null){
 			found = tsk_true;
 		}
 		tsk_safeobj_unlock(self);
 	}
 	return found;
 }
 
 // it's up to the caller to release the returned object
 tsip_dialog_t* tsip_dialog_layer_find(const tsip_dialog_layer_t *self, const char* callid, const char* to_tag, const char* from_tag, tsip_request_type_t type, tsk_bool_t *cid_matched)
 {
 	tsip_dialog_t *ret = tsk_null;
 	tsip_dialog_t *dialog;
 	tsk_list_item_t *item;
 
 	*cid_matched = tsk_false;
 	
 	tsk_safeobj_lock(self);
 
 	tsk_list_foreach(item, self->dialogs){
 		dialog = item->data;
 		if(tsk_strequals(dialog->callid, callid)){
 			tsk_bool_t is_cancel = (type == tsip_CANCEL); // Incoming CANCEL
 			tsk_bool_t is_register = (type == tsip_REGISTER); // Incoming REGISTER
 			tsk_bool_t is_notify = (type == tsip_NOTIFY); // Incoming NOTIFY
 			*cid_matched = tsk_true;
 			/* CANCEL Request will have the same local tag than the INVITE request
 				the remote tag could be null if the CANCEL request is received immediately after a 100 Trying
 			*/
 			if((is_cancel || tsk_strequals(dialog->tag_local, from_tag)) && (!dialog->tag_remote || tsk_strequals(dialog->tag_remote, to_tag))){
 				ret = tsk_object_ref(dialog);
 				break;
 			}
 			/* REGISTER is dialogless which means that each reREGISTER or unREGISTER will have empty to tag  */
 			if(is_register /* Do not check tags */){
 				ret = tsk_object_ref(dialog);
 				break;
 			}
 			/*	NOTIFY could arrive before the 200 SUBSCRIBE => This is why we don't try to match both tags
 			 
 				RFC 3265 - 3.1.4.4. Confirmation of Subscription Creation
 				Due to the potential for both out-of-order messages and forking, the
 				subscriber MUST be prepared to receive NOTIFY messages before the
 				SUBSCRIBE transaction has completed.
 			 */
 			if(is_notify /* Do not check tags */){
 				ret = tsk_object_ref(dialog);
 				break;
 			}
 		}
 	}
 
 	tsk_safeobj_unlock(self);
 
 	return ret;
 }
 
 tsk_size_t tsip_dialog_layer_count_active_calls(tsip_dialog_layer_t *self)
 {
 	tsk_size_t count = 0;
 
 	tsip_dialog_t *dialog;
 	tsk_list_item_t *item;
 
 	tsk_safeobj_lock(self);
 
 	tsk_list_foreach(item, self->dialogs) {
 		if ((dialog = item->data) && dialog->type == tsip_dialog_INVITE && dialog->state != tsip_initial && dialog->state != tsip_terminated) {
 			++count;
 		}
 	}
 
 	tsk_safeobj_unlock(self);
 
 	return count;
 }
 
 /** Hangup all dialogs starting by non-REGISTER  */
 int tsip_dialog_layer_shutdownAll(tsip_dialog_layer_t *self)
 {
 	if(self){
 		tsk_bool_t wait = tsk_false;
 		tsk_list_item_t *item;
 		tsip_dialog_t *dialog;
 		tsip_dialog_type_t regtype = tsip_dialog_REGISTER;
 
 		if(!self->shutdown.inprogress){
 			self->shutdown.inprogress = tsk_true;
 			if (!self->shutdown.condwait) {
 				self->shutdown.condwait = tsk_condwait_create();
 			}
 		}
 		
 		tsk_safeobj_lock(self);
 		if(tsk_list_count(self->dialogs, pred_find_dialog_by_not_type, &regtype)){
 			/* There are non-register dialogs ==> phase-1 */
 			goto phase1;
 		}
 		else if(tsk_list_count(self->dialogs, pred_find_dialog_by_type, &regtype)){
 			/* There are one or more register dialogs ==> phase-2 */
 			goto phase2;
 		}
 		else{
 			tsk_safeobj_unlock(self);
 			goto done;
 		}
 
 phase1:
 		/* Phase 1 - shutdown all except register and silent_hangup */
 		TSK_DEBUG_INFO("== Shutting down - Phase-1 started ==");
 phase1_loop:
 		tsk_list_foreach(item, self->dialogs){
 			dialog = item->data;
 			if(dialog->type != tsip_dialog_REGISTER && !dialog->ss->silent_hangup){
 				item = tsk_object_ref(item);
 				if(!tsip_dialog_shutdown(dialog, tsk_null)){
 					wait = tsk_true;
 				}
 
 				// if "tsip_dialog_shutdown()" remove the dialog, then
 				// "self->dialogs" will be unsafe
 				if(!(item = tsk_object_unref(item))){
 					goto phase1_loop;
 				}
 			}
 		}
 		tsk_safeobj_unlock(self);
 		
 		/* wait until phase-1 is completed */
 		if(wait){
 			tsk_condwait_timedwait(self->shutdown.condwait, TSIP_DIALOG_SHUTDOWN_TIMEOUT);
 		}
 		
 		/* lock and goto phase2 */
 		tsk_safeobj_lock(self);
 		wait = tsk_false;
 		goto phase2;
 
 phase2:
 		/* Phase 2 - unregister */
 		TSK_DEBUG_INFO("== Shutting down - Phase-2 started ==");
 		self->shutdown.phase2 = tsk_true;
 phase2_loop:
 		tsk_list_foreach(item, self->dialogs){
 			dialog = item->data;
 			if(dialog->type == tsip_dialog_REGISTER){
 				item = tsk_object_ref(item);
 				if(!tsip_dialog_shutdown(dialog, tsk_null)){
 					wait = tsk_true;
 				}
 				// if "tsip_dialog_shutdown()" remove the dialog, then
 				// "self->dialogs" will be unsafe 
 				if(!(item = tsk_object_unref(item))){
 					goto phase2_loop;
 				}
 			}
 		}
 		tsk_safeobj_unlock(self);
 
 		/* wait until phase-2 is completed */
 		if(wait){
 			tsk_condwait_timedwait(self->shutdown.condwait, TSIP_DIALOG_SHUTDOWN_TIMEOUT);
 		}
 
 
 		/* Phase 3 - silenthangup (dialogs will be terminated immediately) */
 		TSK_DEBUG_INFO("== Shutting down - Phase-3 ==");
 phase3_loop:
 		tsk_list_foreach(item, self->dialogs){
 			dialog = item->data;
 			if(dialog->ss->silent_hangup){
 				item = tsk_object_ref(item);
 				tsip_dialog_shutdown(dialog, tsk_null);
 
 				// if "tsip_dialog_shutdown()" remove the dialog, then
 				// "self->dialogs" will became unsafe while looping
 				if(!(item = tsk_object_unref(item))){
 					goto phase3_loop;
 				}
 			}
 		}
 
 done:
 		TSK_DEBUG_INFO("== Shutting down - Terminated ==");
 		return 0;
 	}
 	return -1;
 }
 
 static void* TSK_STDCALL _tsip_dialog_signal_transport_error_async(void* dialog)
 {
     tsip_dialog_signal_transport_error(TSIP_DIALOG(dialog));
     return tsk_null;
 }
 
 int tsip_dialog_layer_signal_stack_disconnected(tsip_dialog_layer_t *self)
 {
 	tsk_list_item_t *item;
     // use copy  for lock-free code and faster code. also fix issue 172 (https://code.google.com/p/idoubs/issues/detail?id=172)
     tsip_dialogs_L_t *dialogs_copy;
     tsip_dialog_t *dialog;
 	if(!self){
 		TSK_DEBUG_ERROR("Invalid parameter");
 		return -1;
 	}
     
     if (!(dialogs_copy = tsk_list_create())) {
         TSK_DEBUG_ERROR("Failed to create list");
 		return -1;
     }
 
 	tsk_safeobj_lock(self);
     tsk_list_pushback_list(dialogs_copy, self->dialogs);
     tsk_safeobj_unlock(self);
     
     tsk_list_foreach(item, dialogs_copy){
         if((dialog = TSIP_DIALOG(item->data))){
             tsip_dialog_signal_transport_error(dialog);
         }
     }
     TSK_OBJECT_SAFE_FREE(dialogs_copy);
 	return 0;
 }
 
 int tsip_dialog_layer_signal_peer_disconnected(tsip_dialog_layer_t *self, const struct tsip_transport_stream_peer_s* peer)
 {
 	tsip_dialog_t *dialog;
 	const tsk_list_item_t *item;
 
 	if(!self || !peer){
 		TSK_DEBUG_ERROR("Invalid parameter");
 		return -1;
 	}
     
     //!\ must not lock the entire layer
 
 	// tsk_safeobj_lock(self);
 
 	tsk_list_lock(peer->dialogs_cids);
 	tsk_list_foreach(item, peer->dialogs_cids){
 		if((dialog = tsip_dialog_layer_find_by_callid(self, TSK_STRING_STR(item->data)))){
 			tsip_dialog_signal_transport_error(dialog);
 			TSK_OBJECT_SAFE_FREE(dialog);
 		}
 		else{
 			// To avoid this WARN, you should call tsip_dialog_layer_have_dialog_with_callid() before adding a callid to a peer
 			TSK_DEBUG_WARN("Stream peer holds call-id='%s' but the dialog layer doesn't know it", TSK_STRING_STR(item->data));
 		}
 	}
 	tsk_list_unlock(peer->dialogs_cids);
 
 	// tsk_safeobj_unlock(self);
 
 	return 0;
 }
 
 int tsip_dialog_layer_remove_callid_from_stream_peers(tsip_dialog_layer_t *self, const char* callid)
 {
 	if(self){
 		return tsip_transport_layer_remove_callid_from_stream_peers(self->stack->layer_transport, callid);
 	}
 	TSK_DEBUG_ERROR("Invalid parameter");
 	return -1;
 }
 
 /* the caller of this function must unref() the returned object */
 tsip_dialog_t* tsip_dialog_layer_new(tsip_dialog_layer_t *self, tsip_dialog_type_t type, const tsip_ssession_t *ss)
 {
 	tsip_dialog_t* ret = tsk_null;
 	tsip_dialog_t* dialog;
 	if(!self){
 		TSK_DEBUG_ERROR("Invalid parameter");
 		goto bail;
 	}
 
 	switch(type){
 		case tsip_dialog_INVITE:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_invite_create(ss, tsk_null))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_MESSAGE:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_message_create(ss))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_INFO:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_info_create(ss))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_OPTIONS:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_options_create(ss))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_PUBLISH:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_publish_create(ss))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_REGISTER:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_register_create(ss, tsk_null))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 		case tsip_dialog_SUBSCRIBE:
 			{
 				if((dialog = (tsip_dialog_t*)tsip_dialog_subscribe_create(ss))){
 					ret = tsk_object_ref(dialog);
 					tsk_list_push_back_data(self->dialogs, (void**)&dialog);
 				}
 				break;
 			}
 
 		default:
 			{
 				TSK_DEBUG_ERROR("Dialog type not supported.");
 				break;
 			}
 	}
 
 bail:
 	return ret;
 }
 
 int tsip_dialog_layer_remove(tsip_dialog_layer_t *self, const tsip_dialog_t *dialog)
 {
 	if(dialog && self){
 		tsip_dialog_type_t regtype = tsip_dialog_REGISTER;
 		tsk_safeobj_lock(self);
 		
 		/* remove the dialog */
 		tsk_list_remove_item_by_data(self->dialogs, dialog);
 		
 		/* whether shutting down? */
 		if(self->shutdown.inprogress){
 			if(self->shutdown.phase2){ /* Phase 2 (all non-REGISTER and silent dialogs have been removed) */
 				if(tsk_list_count(self->dialogs, pred_find_dialog_by_type, &regtype) == 0){
 					/* alert only if there is not REGISTER dialog (ignore silents) */
 					TSK_DEBUG_INFO("== Shutting down - Phase-2 completed ==");
 					tsk_condwait_broadcast(self->shutdown.condwait);
 				}
 			}
 			else{ /* Phase 1 */
 				if(tsk_list_count(self->dialogs, pred_find_dialog_by_not_type, &regtype) == 0){
 					/* alert only if all dialogs except REGISTER have been removed */
 					TSK_DEBUG_INFO("== Shutting down - Phase-1 completed ==");
 					tsk_condwait_broadcast(self->shutdown.condwait);
 				}
 			}
 		}
 
 		tsk_safeobj_unlock(self);
 
 		return 0;
 	}
 
 	return -1;
 }
 
 // this function is only called if no transaction match
 // for responses, the transaction will always match
 int tsip_dialog_layer_handle_incoming_msg(const tsip_dialog_layer_t *self, tsip_message_t* message)
 {
 	int ret = -1;
 	tsk_bool_t cid_matched;
 	tsip_dialog_t* dialog;
 	tsip_transac_t* transac = tsk_null;
 	const tsip_transac_layer_t *layer_transac = self->stack->layer_transac;
 
 	if(!layer_transac){
 		goto bail;
 	}
 	
 	//tsk_safeobj_lock(self);
 	dialog = tsip_dialog_layer_find(self, message->Call_ID->value, 
 		TSIP_MESSAGE_IS_RESPONSE(message) ? message->To->tag : message->From->tag, 
 		TSIP_MESSAGE_IS_RESPONSE(message) ? message->From->tag : message->To->tag, 
 		TSIP_MESSAGE_IS_REQUEST(message) ? TSIP_MESSAGE_AS_REQUEST(message)->line.request.request_type : tsip_NONE, 
 		&cid_matched);
 	//tsk_safeobj_unlock(self);
 	
 	if(dialog){
 		if(TSIP_REQUEST_IS_CANCEL(message) || TSIP_REQUEST_IS_ACK(message)){
 			ret = dialog->callback(dialog, tsip_dialog_i_msg, message);
 			tsk_object_unref(dialog);
 			goto bail;
 		}
 		else{
 			static tsk_bool_t isCT = tsk_false;
 			tsip_transac_dst_t* dst = tsip_transac_dst_dialog_create(dialog);
 			transac = tsip_transac_layer_new(
 				layer_transac, 
 				isCT,
 				message, 
 				dst
 			);
 			TSK_OBJECT_SAFE_FREE(dst);
 			TSK_OBJECT_SAFE_FREE(dialog);
 		}
 	}
 	else{
 		/* MediaProxyMode : forward all non-INVITE messages */
 		if(self->stack->network.mode == tsip_stack_mode_webrtc2sip){
 			tsk_bool_t b2bua;
 			
 			if(TSIP_MESSAGE_IS_REQUEST(message)){
 				// requests received over TCP/TLS/UDP must contain "ws-src-ip" and "ws-src-port" parameters
 				if(!TNET_SOCKET_TYPE_IS_WS(message->src_net_type) && !TNET_SOCKET_TYPE_IS_WSS(message->src_net_type)){
 					const char* ws_src_ip = tsk_params_get_param_value(message->line.request.uri->params, "ws-src-ip");
 					const tnet_port_t ws_src_port = (tnet_port_t)tsk_params_get_param_value_as_int(message->line.request.uri->params, "ws-src-port");
 					if(!tsip_transport_layer_have_stream_peer_with_remote_ip(self->stack->layer_transport, ws_src_ip, ws_src_port)){
 						if(!TSIP_REQUEST_IS_ACK(message)){ // ACK do not expect response
 #if 0 // code commented because when using mjserver, rejecting the forked INVITE terminate all dialogs: have to check if it's conform to RFC 3261 or not
 							tsip_response_t* response = tsip_response_new(488, "WebSocket Peer not connected", message);
 							ret = tsip_transport_layer_send(self->stack->layer_transport, "no-branch", response);
 							TSK_OBJECT_SAFE_FREE(response);
 							return ret;
 #else
 							TSK_DEBUG_INFO("Request for peer at %s:%d cannot be delivered", ws_src_ip, ws_src_port);
 #endif
 						}
 						return 0;
 					}
 				}
 			}
 
 			// "rtcweb-breaker" parameter will be in the Contact header for outgoing request and in the request-uri for incoming requests
 			b2bua = TSIP_REQUEST_IS_INVITE(message) && message->Contact && message->Contact->uri &&
 					(tsk_striequals(tsk_params_get_param_value(message->Contact->uri->params, "rtcweb-breaker"), "yes")
 					|| tsk_striequals(tsk_params_get_param_value(message->line.request.uri->params, "rtcweb-breaker"), "yes"));
 			
 			if(!b2bua){
 				// forward the message
 				static tsk_bool_t isCT = tsk_true;
 				tsip_transac_dst_t* dst;
 				tsip_transac_t* transac;
 
 				TSIP_MESSAGE(message)->update = tsk_true; // update AoR and Via
 				if((dst = tsip_transac_dst_net_create(TSIP_STACK(self->stack)))){
 					if((transac = tsip_transac_layer_new(self->stack->layer_transac, isCT, message, dst))){
 						ret = tsip_transac_start(transac, message);
 						TSK_OBJECT_SAFE_FREE(transac);
 					}
 					TSK_OBJECT_SAFE_FREE(dst);
 				}
 				return ret;
 			}
 		}
 
 		if(TSIP_MESSAGE_IS_REQUEST(message)){
 			tsip_ssession_t* ss = tsk_null;
 			tsip_dialog_t* newdialog = tsk_null;
 			
 			switch(message->line.request.request_type){
 				case tsip_MESSAGE:
 					{	/* Server incoming MESSAGE */
 						if((ss = tsip_ssession_create_2(self->stack, message))){
 							newdialog = (tsip_dialog_t*)tsip_dialog_message_create(ss);
 						}
 						break;
 					}
 				case tsip_INFO:
 					{	/* Server incoming INFO */
 						if((ss = tsip_ssession_create_2(self->stack, message))){
 							newdialog = (tsip_dialog_t*)tsip_dialog_info_create(ss);
 						}
 						break;
 					}
 				case tsip_OPTIONS:
 					{	/* Server incoming OPTIONS */
 						if((ss = tsip_ssession_create_2(self->stack, message))){
 							newdialog = (tsip_dialog_t*)tsip_dialog_options_create(ss);
 						}
 						break;
 					}
 
 				case tsip_REGISTER:
 					{	/* incoming REGISTER */
 						if((ss = tsip_ssession_create_2(self->stack, message))){
 							newdialog = (tsip_dialog_t*)tsip_dialog_register_create(ss, message->Call_ID ? message->Call_ID->value : tsk_null);
 						}
 						break;
 					}
 
 				case tsip_INVITE:
 					{	/* incoming INVITE */
 						if((ss = tsip_ssession_create_2(self->stack, message))){
 							newdialog = (tsip_dialog_t*)tsip_dialog_invite_create(ss, message->Call_ID ? message->Call_ID->value : tsk_null);
 						}
 						break;
 					}
 
 				default:
 					{
 						break;
 					}
 			}//switch
 
 			// for new dialog, create a new transac and start it later
 			if(newdialog){
 				static const tsk_bool_t isCT = tsk_false;
 				tsip_transac_dst_t* dst = tsip_transac_dst_dialog_create(newdialog);
 				transac = tsip_transac_layer_new(
 					layer_transac, 
 					isCT,
 					message, 
 					dst
 				);
 				if(message->local_fd > 0 && TNET_SOCKET_TYPE_IS_STREAM(message->src_net_type)) {
 					tsip_dialog_set_connected_fd(newdialog, message->local_fd);
 				}
 				tsk_list_push_back_data(self->dialogs, (void**)&newdialog); /* add new dialog to the layer */
 				TSK_OBJECT_SAFE_FREE(dst);
 			}
 
 			/* The dialog will become the owner of the SIP session
 			* => when destoyed => SIP session will be destroyed, unless the user-end takes ownership() */
 			TSK_OBJECT_SAFE_FREE(ss);
 		}
 	}
 
 	if(transac){
 		ret = tsip_transac_start(transac, message);
 		tsk_object_unref(transac);
 	}
 	/* - No transaction match for the SIP request
 	   - ACK do not expect any response (http://code.google.com/p/imsdroid/issues/detail?id=420)
 	*/
 	else if(TSIP_MESSAGE_IS_REQUEST(message) && !TSIP_REQUEST_IS_ACK(message)){
 		const tsip_transport_layer_t *layer;
 		tsip_response_t* response = tsk_null;
 		if(!dialog && cid_matched){
 			dialog = tsip_dialog_layer_find_by_callid((tsip_dialog_layer_t *)self, message->Call_ID->value);
 		}
 
 		if((layer = self->stack->layer_transport)){	
 			if(cid_matched){ /* We are receiving our own message. */
 				response = tsip_response_new(482, "Loop Detected (Check your iFCs)", message);
 				if(response && !response->To->tag){/* Early dialog? */
 					response->To->tag = tsk_strdup("organization");
 				}
 			}
 			else{
 				switch(message->line.request.request_type){
 					case tsip_OPTIONS: // Hacked to work on Tiscali IMS networks
 					case tsip_INFO:
 						response = tsip_response_new(405, "Method Not Allowed", message);
 						break;
 					default:
 						response = tsip_response_new(481, "Dialog/Transaction Does Not Exist", message);
 						break;
 				}
 			}
 			if(response){
 				if(dialog && TSIP_DIALOG_GET_SS(dialog)){
 					tsk_strupdate(&response->sigcomp_id, TSIP_DIALOG_GET_SS(dialog)->sigcomp_id);
 				}
 				ret = tsip_transport_layer_send(layer, response->firstVia ? response->firstVia->branch : "no-branch", response);
 				TSK_OBJECT_SAFE_FREE(response);
 			}
 		}
 
 		TSK_OBJECT_SAFE_FREE(dialog);
 	}
 	
 bail:
 	return ret;
 }
 
 
 
 
 
 //========================================================
 //	Dialog layer object definition
 //
 static tsk_object_t* tsip_dialog_layer_ctor(tsk_object_t * self, va_list * app)
 {
 	tsip_dialog_layer_t *layer = self;
 	if(layer){
 		layer->stack = va_arg(*app, const tsip_stack_t *);
 		layer->dialogs = tsk_list_create();
 
 		tsk_safeobj_init(layer);
 	}
 	return self;
 }
 
 static tsk_object_t* tsip_dialog_layer_dtor(tsk_object_t * self)
 { 
 	tsip_dialog_layer_t *layer = self;
 	if(layer){
 		TSK_OBJECT_SAFE_FREE(layer->dialogs);
 
 		/* condwait */
 		if(layer->shutdown.condwait){
 			tsk_condwait_destroy(&layer->shutdown.condwait);
 		}
 
 		tsk_safeobj_deinit(layer);
 
 		TSK_DEBUG_INFO("*** Dialog Layer destroyed ***");
 	}
 	return self;
 }
 
 static int tsip_dialog_layer_cmp(const tsk_object_t *obj1, const tsk_object_t *obj2)
 {
 	return -1;
 }
 
 static const tsk_object_def_t tsip_dialog_layer_def_s = 
 {
 	sizeof(tsip_dialog_layer_t),
 	tsip_dialog_layer_ctor, 
 	tsip_dialog_layer_dtor,
 	tsip_dialog_layer_cmp, 
 };
 const tsk_object_def_t *tsip_dialog_layer_def_t = &tsip_dialog_layer_def_s;