/*
  * $Id$
  *

  * Copyright (C) 2001-2003 FhG Fokus

  *
  * This file is part of ser, a free SIP server.
  *
  * ser 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
  *
  * For a license to use the ser software under conditions
  * other than those described here, or to purchase support for this
  * software, please contact iptel.org by e-mail at the following addresses:
  *   info@iptel.org
  *
  * ser 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
  *

  * History:
  * -------
  * 2003-03-29 Created by janakj

  * 2003-07-08 added wrapper to calculate_hooks, needed by b2bua (dcm)

  */
 
 
 #include <string.h>

 #include "../../mem/shm_mem.h"

 #include "../../dprint.h"
 #include "../../parser/contact/parse_contact.h"
 #include "../../parser/parse_to.h"
 #include "../../parser/parse_from.h"

 #include "../../parser/parse_uri.h"

 #include "../../trim.h"
 #include "../../ut.h"

 #include "../../config.h"

 #include "dlg.h"

 #include "t_reply.h"
 #include "../../parser/parser_f.h"

 /* next added to allow automatical tag generation */
 #include "callid.h"
 #include "uac.h"

 
 #define NORMAL_ORDER 0  /* Create route set in normal order - UAS */
 #define REVERSE_ORDER 1 /* Create route set in reverse order - UAC */
 

 #define ROUTE_PREFIX "Route: "
 #define ROUTE_PREFIX_LEN (sizeof(ROUTE_PREFIX) - 1)
 
 #define ROUTE_SEPARATOR "," CRLF "       "
 #define ROUTE_SEPARATOR_LEN (sizeof(ROUTE_SEPARATOR) - 1)
 

 /*** Temporary hack ! */
 /*
  * This function skips name part
  * uri parsed by parse_contact must be used
  * (the uri must not contain any leading or
  *  trailing part and if angle bracket were
  *  used, right angle bracket must be the
  *  last character in the string)
  *
  * _s will be modified so it should be a tmp
  * copy
  */
 void get_raw_uri(str* _s)
 {
         char* aq;
         
         if (_s->s[_s->len - 1] == '>') {
                 aq = find_not_quoted(_s, '<');
                 _s->len -= aq - _s->s + 2;
                 _s->s = aq + 1;
         }
 }
 
 

 /*

  * Make a copy of a str structure using shm_malloc

  */
 static inline int str_duplicate(str* _d, str* _s)
 {

 	_d->s = shm_malloc(_s->len);

 	if (!_d->s) {
 		LOG(L_ERR, "str_duplicate(): No memory left\n");
 		return -1;
 	}
 	
 	memcpy(_d->s, _s->s, _s->len);
 	_d->len = _s->len;
 	return 0;
 }
 
 

 /*
  * Calculate dialog hooks
  */
 static inline int calculate_hooks(dlg_t* _d)
 {
 	str* uri;
 	struct sip_uri puri;
 	param_hooks_t hooks;
 	param_t* params;
 
 	if (_d->route_set) {
 		uri = &_d->route_set->nameaddr.uri;
 		if (parse_uri(uri->s, uri->len, &puri) < 0) {
 			LOG(L_ERR, "calculate_hooks(): Error while parsing URI\n");
 			return -1;
 		}
 
 		if (parse_params(&puri.params, CLASS_URI, &hooks, &params) < 0) {
 			LOG(L_ERR, "calculate_hooks(): Error while parsing parameters\n");
 			return -2;
 		}
 		free_params(params);
 		
 		if (hooks.uri.lr) {
 			if (_d->rem_target.s) _d->hooks.request_uri = &_d->rem_target;
 			else _d->hooks.request_uri = &_d->rem_uri;
 			_d->hooks.next_hop = &_d->route_set->nameaddr.uri;
 			_d->hooks.first_route = _d->route_set;
 		} else {
 			_d->hooks.request_uri = &_d->route_set->nameaddr.uri;
 			_d->hooks.next_hop = _d->hooks.request_uri;
 			_d->hooks.first_route = _d->route_set->next;

 			if (_d->rem_target.len > 0) 
 				_d->hooks.last_route = &_d->rem_target;
 			else 
 				_d->hooks.last_route = NULL; /* ? */

 		}
 	} else {
 		if (_d->rem_target.s) _d->hooks.request_uri = &_d->rem_target;
 		else _d->hooks.request_uri = &_d->rem_uri;

 		
 		if (_d->dst_uri.s) _d->hooks.next_hop = &_d->dst_uri;
 		else _d->hooks.next_hop = _d->hooks.request_uri;

 
 		/*
 		 * the routes in the hooks need to be reset because if the route_set was dropped somewhere else
 		 * then these will remain set without the actual routes existing any more
 		 */
 		_d->hooks.first_route = 0;
 		_d->hooks.last_route = 0; 

 	}
 

 	if ((_d->hooks.request_uri) && (_d->hooks.request_uri->s) && (_d->hooks.request_uri->len)) {
 		_d->hooks.ru.s = _d->hooks.request_uri->s;
 		_d->hooks.ru.len = _d->hooks.request_uri->len;
 		_d->hooks.request_uri = &_d->hooks.ru;
 		get_raw_uri(_d->hooks.request_uri);
 	}
 	if ((_d->hooks.next_hop) && (_d->hooks.next_hop->s) && (_d->hooks.next_hop->len)) {
 		_d->hooks.nh.s = _d->hooks.next_hop->s;
 		_d->hooks.nh.len = _d->hooks.next_hop->len;
 		_d->hooks.next_hop = &_d->hooks.nh;
 		get_raw_uri(_d->hooks.next_hop);
 	}
 

 	return 0;
 }
 

 /*
  * wrapper to calculate_hooks
  * added by dcm
  */
 int w_calculate_hooks(dlg_t* _d)
 {
 	return calculate_hooks(_d);
 }

 /*
  * Create a new dialog
  */
 int new_dlg_uac(str* _cid, str* _ltag, unsigned int _lseq, str* _luri, str* _ruri, dlg_t** _d)
 {
 	dlg_t* res;

 	str generated_cid;
 	str generated_ltag;
 
 	if (!_cid) { /* if not given, compute new one */
 		generate_callid(&generated_cid);
 		_cid = &generated_cid;
 	}
 	if (_cid && (!_ltag)) { /* if not given, compute new one */
 		generate_fromtag(&generated_ltag, _cid);
 		_ltag = &generated_ltag;
 	}
 	if (_lseq == 0) _lseq = DEFAULT_CSEQ;

 
 	if (!_cid || !_ltag || !_luri || !_ruri || !_d) {
 		LOG(L_ERR, "new_dlg_uac(): Invalid parameter value\n");
 		return -1;
 	}
 

 	res = (dlg_t*)shm_malloc(sizeof(dlg_t));

 	if (res == 0) {
 		LOG(L_ERR, "new_dlg_uac(): No memory left\n");
 		return -2;
 	}

 
 	     /* Clear everything */	

 	memset(res, 0, sizeof(dlg_t));
 	
 	     /* Make a copy of Call-ID */
 	if (str_duplicate(&res->id.call_id, _cid) < 0) return -3;
 	     /* Make a copy of local tag (usually From tag) */
 	if (str_duplicate(&res->id.loc_tag, _ltag) < 0) return -4;
 	     /* Make a copy of local URI (usually From) */
 	if (str_duplicate(&res->loc_uri, _luri) < 0) return -5;
 	     /* Make a copy of remote URI (usually To) */
 	if (str_duplicate(&res->rem_uri, _ruri) < 0) return -6;
 	     /* Make a copy of local sequence (usually CSeq) */
 	res->loc_seq.value = _lseq;
 	     /* And mark it as set */
 	res->loc_seq.is_set = 1;
 
 	*_d = res;

 
 	if (calculate_hooks(*_d) < 0) {
 		LOG(L_ERR, "new_dlg_uac(): Error while calculating hooks\n");

 		/* FIXME: free everything here */

 		shm_free(res);
 		return -2;
 	}

 	return 0;
 }
 
 
 /*
  * Parse Contact header field body and extract URI
  * Does not parse headers !!
  */
 static inline int get_contact_uri(struct sip_msg* _m, str* _uri)
 {
 	contact_t* c;
 
 	_uri->len = 0;

 	_uri->s = 0;

 	if (!_m->contact) return 1;

 
 	if (parse_contact(_m->contact) < 0) {
 		LOG(L_ERR, "get_contact_uri(): Error while parsing Contact body\n");
 		return -2;
 	}
 
 	c = ((contact_body_t*)_m->contact->parsed)->contacts;
 
 	if (!c) {
 		LOG(L_ERR, "get_contact_uri(): Empty body or * contact\n");
 		return -3;
 	}
 
 	_uri->s = c->uri.s;
 	_uri->len = c->uri.len;
 	return 0;
 }
 
 
 /*
  * Extract tag from To header field of a response
  * Doesn't parse message headers !!
  */
 static inline int get_to_tag(struct sip_msg* _m, str* _tag)
 {
 	if (!_m->to) {
 		LOG(L_ERR, "get_to_tag(): To header field missing\n");
 		return -1;
 	}
 
 	if (get_to(_m)->tag_value.len) {
 		_tag->s = get_to(_m)->tag_value.s;
 		_tag->len = get_to(_m)->tag_value.len;
 	} else {
 		_tag->len = 0;
 	}
 
 	return 0;
 }
 
 
 /*
  * Extract tag from From header field of a request
  */
 static inline int get_from_tag(struct sip_msg* _m, str* _tag)
 {
 	if (parse_from_header(_m) == -1) {
 		LOG(L_ERR, "get_from_tag(): Error while parsing From header\n");
 		return -1;
 	}
 
 	if (get_from(_m)->tag_value.len) {
 		_tag->s = get_from(_m)->tag_value.s;
 		_tag->len = get_from(_m)->tag_value.len;
 	} else {
 		_tag->len = 0;
 	}
 
 	return 0;
 }
 
 
 /*
  * Extract Call-ID value
  * Doesn't parse headers !!
  */
 static inline int get_callid(struct sip_msg* _m, str* _cid)
 {
 	if (_m->callid == 0) {
 		LOG(L_ERR, "get_callid(): Call-ID not found\n");
 		return -1;
 	}
 
 	_cid->s = _m->callid->body.s;
 	_cid->len = _m->callid->body.len;
 	trim(_cid);
 	return 0;
 }
 

 static rr_t *revert_route(rr_t *r)
 {
 	rr_t *a, *b;
 
 	a = NULL;
 
 	while (r) {
 		b = r->next;
 		r->next = a;
 		a = r;
 		r = b;
 	}
 
 	return a;
 }

 
 /*
  * Create a copy of route set either in normal or reverse order
  */
 static inline int get_route_set(struct sip_msg* _m, rr_t** _rs, unsigned char _order)
 {
 	struct hdr_field* ptr;
 	rr_t* last, *p, *t;
 	
 	last = 0;
 
 	ptr = _m->record_route;
 	while(ptr) {

 		if (ptr->type == HDR_RECORDROUTE_T) {

 			if (parse_rr(ptr) < 0) {
 				LOG(L_ERR, "get_route_set(): Error while parsing Record-Route body\n");
 				goto error;
 			}
 
 			p = (rr_t*)ptr->parsed;

 			if (shm_duplicate_rr(&t, p) < 0) {
 				LOG(L_ERR, "get_route_set(): Error while duplicating rr_t\n");
 				goto error;

 			}

 			if (!*_rs) *_rs = t;
 			if (last) last->next = t;
 			last = t;
 			while (last->next) last = last->next; /* !!! there may be more routes in one hdr field !!! */
 

 		}
 		ptr = ptr->next;
 	}

 	if ((*_rs) && (_order != NORMAL_ORDER)) {
 		/* better to revert the route outside of cycle above */
 		*_rs = revert_route(*_rs);
 	}

 	
 	return 0;
 
  error:

 	shm_free_rr(_rs);

 	return -1;
 }
 

 /*
  * Extract method from CSeq header field
  */
 static inline int get_cseq_method(struct sip_msg* _m, str* _method)
 {
 	if (!_m->cseq && ((parse_headers(_m, HDR_CSEQ_F, 0) == -1) || !_m->cseq)) {
 		LOG(L_ERR, "get_cseq_method(): Error while parsing CSeq\n");
 		return -1;
 	}
 
 	_method->s = get_cseq(_m)->method.s;
 	_method->len = get_cseq(_m)->method.len;
 	return 0;
 }
 
 
 static inline int refresh_dialog_resp(struct sip_msg* _m, 
 		target_refresh_t is_target_refresh)
 {
 	str method;
 	
 	switch (is_target_refresh) {
 		case IS_NOT_TARGET_REFRESH: 
 			return 0;
 		case IS_TARGET_REFRESH: 
 			return 1;
 		case TARGET_REFRESH_UNKNOWN: 
 			if (get_cseq_method(_m, &method) < 0) return 0; /* error */
 			if ((method.len == 6) && !memcmp("INVITE", method.s, 6)) 
 				return 1;
 			else return 0;
 	}
 	return 0;
 }
 		
 static inline int refresh_dialog_req(struct sip_msg* _m, target_refresh_t is_target_refresh)
 {
 	switch (is_target_refresh) {
 		case IS_NOT_TARGET_REFRESH: 
 			return 0;
 		case IS_TARGET_REFRESH: 
 			return 1;
 		case TARGET_REFRESH_UNKNOWN: 
 			return (_m->first_line.u.request.method_value == METHOD_INVITE);
 			break;
 	}
 	return 0;
 }

 
 /*

  * Extract all necessary information from a response and put it

  * in a dialog structure
  */
 static inline int response2dlg(struct sip_msg* _m, dlg_t* _d)
 {
 	str contact, rtag;
 
 	     /* Parse the whole message, we will need all Record-Route headers */

 	if (parse_headers(_m, HDR_EOH_F, 0) == -1) {

 		LOG(L_ERR, "response2dlg(): Error while parsing headers\n");

 		return -1;
 	}
 	
 	if (get_contact_uri(_m, &contact) < 0) return -2;

 	if (_d->rem_target.s) {
 		shm_free(_d->rem_target.s);
 		_d->rem_target.s = 0; 
 		_d->rem_target.len = 0;
 	}

 	if (_d->dst_uri.s) {
 		shm_free(_d->dst_uri.s);
 		_d->dst_uri.s = 0; 
 		_d->dst_uri.len = 0;
 	}

 	if (contact.len && str_duplicate(&_d->rem_target, &contact) < 0) return -3;
 	
 	if (get_to_tag(_m, &rtag) < 0) goto err1;
 	if (rtag.len && str_duplicate(&_d->id.rem_tag, &rtag) < 0) goto err1;
 	
 	if (get_route_set(_m, &_d->route_set, REVERSE_ORDER) < 0) goto err2;
 
 	return 0;
  err2:

 	if (_d->id.rem_tag.s) shm_free(_d->id.rem_tag.s);

 	_d->id.rem_tag.s = 0;
 	_d->id.rem_tag.len = 0;
 
  err1:

 	if (_d->rem_target.s) shm_free(_d->rem_target.s);

 	_d->rem_target.s = 0;
 	_d->rem_target.len = 0;
 	return -4;
 }
 
 
 /*
  * Handle dialog in DLG_NEW state, we will be processing the
  * first response
  */
 static inline int dlg_new_resp_uac(dlg_t* _d, struct sip_msg* _m)
 {
 	int code;
 	     /*
 	      * Dialog is in DLG_NEW state, we will copy remote
 	      * target URI, remote tag if present, and route-set 
 	      * if present. And we will transit into DLG_CONFIRMED 
 	      * if the response was 2xx and to DLG_DESTROYED if the 
 	      * request was a negative final response.
 	      */
 
 	code = _m->first_line.u.reply.statuscode;
 
 	if (code < 200) {
 		     /* A provisional response, do nothing, we could
 		      * update remote tag and route set but we will do that
 		      * for a positive final response anyway and I don't want
 		      * bet on presence of these fields in provisional responses
 		      *
 		      * Send a request to jan@iptel.org if you need to update
 		      * the structures here
 		      */
 	} else if ((code >= 200) && (code < 299)) {
 		     /* A final response, update the structures and transit
 		      * into DLG_CONFIRMED
 		      */
 		if (response2dlg(_m, _d) < 0) return -1;
 		_d->state = DLG_CONFIRMED;

 
 		if (calculate_hooks(_d) < 0) {
 			LOG(L_ERR, "dlg_new_resp_uac(): Error while calculating hooks\n");
 			return -2;
 		}

 	} else {
 		     /* 
 		      * A negative final response, mark the dialog as destroyed

 		      * Again, I do not update the structures here because it

 		      * makes no sense to me, a dialog shouldn't be used after
 		      * it is destroyed
 		      */
 		_d->state = DLG_DESTROYED;
 		     /* Signalize the termination with positive return value */
 		return 1;
 	}
 
 	return 0;
 }
 
 
 /*
  * Handle dialog in DLG_EARLY state, we will be processing either
  * next provisional response or a final response
  */
 static inline int dlg_early_resp_uac(dlg_t* _d, struct sip_msg* _m)
 {
 	int code;
 	code = _m->first_line.u.reply.statuscode;	
 
 	if (code < 200) {
 		     /* We are in early state already, do nothing
 		      */
 	} else if ((code >= 200) && (code <= 299)) {

 		/* Warning - we can handle here response for non-initial request (for
 		 * example UPDATE within early INVITE/BYE dialog) and move into
 		 * confirmed state may be error! But this depends on dialog type... */
 		

 		     /* Same as in dlg_new_resp_uac */
 		     /* A final response, update the structures and transit
 		      * into DLG_CONFIRMED
 		      */
 		if (response2dlg(_m, _d) < 0) return -1;
 		_d->state = DLG_CONFIRMED;

 
 		if (calculate_hooks(_d) < 0) {
 			LOG(L_ERR, "dlg_early_resp_uac(): Error while calculating hooks\n");
 			return -2;
 		}

 	} else {
 		     /* Else terminate the dialog */
 		_d->state = DLG_DESTROYED;
 		     /* Signalize the termination with positive return value */
 		return 1;
 	}
 
 	return 0;
 }
 
 
 /*
  * Handle dialog in DLG_CONFIRMED state, we will be processing
  * a response to a request sent within a dialog
  */

 static inline int dlg_confirmed_resp_uac(dlg_t* _d, struct sip_msg* _m, 
 		target_refresh_t is_target_refresh)

 {
 	int code;

 	str contact;

 
 	code = _m->first_line.u.reply.statuscode;	
 
 	     /* Dialog has been already confirmed, that means we received
 	      * a response to a request sent within the dialog. We will
 	      * update remote target URI if and only if the message sent was
 	      * a target refresher. 
 	      */
 
 	     /* IF we receive a 481 response, terminate the dialog because
 	      * the remote peer indicated that it didn't have the dialog
 	      * state anymore, signal this termination with a positive return
 	      * value
 	      */
 	if (code == 481) {
 		_d->state = DLG_DESTROYED;
 		return 1;
 	}
 
 	     /* Do nothing if not 2xx */
 	if ((code < 200) || (code >= 300)) return 0;
 	

 	if (refresh_dialog_resp(_m, is_target_refresh)) {

 		     /* Get contact if any and update remote target */

 		if (parse_headers(_m, HDR_CONTACT_F, 0) == -1) {

 			LOG(L_ERR, "dlg_confirmed_resp_uac(): Error while parsing headers\n");
 			return -2;
 		}
 
 		     /* Try to extract contact URI */
 		if (get_contact_uri(_m, &contact) < 0) return -3;
 		     /* If there is a contact URI */
 		if (contact.len) {

 			     /* Free old remote target and destination uri if any */

 			if (_d->rem_target.s) shm_free(_d->rem_target.s);

 			if (_d->dst_uri.s) {
 				shm_free(_d->dst_uri.s);
 				_d->dst_uri.s = 0;
 				_d->dst_uri.len = 0;
 			}
 				

 			     /* Duplicate new remote target */
 			if (str_duplicate(&_d->rem_target, &contact) < 0) return -4;
 		}

 
 		calculate_hooks(_d);

 	}
 
 	return 0;
 }
 
 
 /*
  * A response arrived, update dialog
  */

 int dlg_response_uac(dlg_t* _d, struct sip_msg* _m, 
 		target_refresh_t is_target_refresh)

 {
 	if (!_d || !_m) {
 		LOG(L_ERR, "dlg_response_uac(): Invalid parameter value\n");
 		return -1;
 	}
 
 	     /* The main dispatcher */
 	switch(_d->state) {
 	case DLG_NEW:       
 		return dlg_new_resp_uac(_d, _m);
 
 	case DLG_EARLY:     
 		return dlg_early_resp_uac(_d, _m);
 
 	case DLG_CONFIRMED: 

 		return dlg_confirmed_resp_uac(_d, _m, is_target_refresh);

 
 	case DLG_DESTROYED:

 		LOG(L_DBG, "dlg_response_uac(): Cannot handle destroyed dialog\n");

 		return -2;
 	}
 
 	LOG(L_ERR, "dlg_response_uac(): Error in switch statement\n");
 	return -3;
 }
 
 
 /*
  * Get CSeq number
  * Does not parse headers !!
  */
 static inline int get_cseq_value(struct sip_msg* _m, unsigned int* _cs)
 {
 	str num;
 
 	if (_m->cseq == 0) {
 		LOG(L_ERR, "get_cseq_value(): CSeq header not found\n");
 		return -1;
 	}
 
 	num.s = get_cseq(_m)->number.s;
 	num.len = get_cseq(_m)->number.len;
 
 	trim_leading(&num);
 	if (str2int(&num, _cs) < 0) {
 		LOG(L_ERR, "get_cseq_value(): Error while converting cseq number\n");
 		return -2;
 	}
 	return 0;
 }
 
 
 /*
  * Copy To or From URI without tag parameter
  */
 static inline int get_dlg_uri(struct hdr_field* _h, str* _s)
 {

 	struct to_param* ptr, *prev;

 	struct to_body* body;
 	char* tag = 0; /* Makes gcc happy */
 	int tag_len = 0, len;
 
 	if (!_h) {
 		LOG(L_ERR, "get_dlg_uri(): Header field not found\n");
 		return -1;
 	}
 
 	     /* From was already parsed when extracting tag
 	      * and To is parsed by default
 	      */
 	
 	body = (struct to_body*)_h->parsed;
 
 	ptr = body->param_lst;

 	prev = 0;

 	while(ptr) {
 		if (ptr->type == TAG_PARAM) break;

 		prev = ptr;

 		ptr = ptr->next;
 	}
 
 	if (ptr) {

 		     /* Tag param found */
 		if (prev) {
 			tag = prev->value.s + prev->value.len;
 		} else {
 			tag = body->body.s + body->body.len;
 		}
 		

 		if (ptr->next) {

 			tag_len = ptr->value.s + ptr->value.len - tag;

 		} else {

 			tag_len = _h->body.s + _h->body.len - tag;

 		}
 	}
 

 	_s->s = shm_malloc(_h->body.len - tag_len);

 	if (!_s->s) {
 		LOG(L_ERR, "get_dlg_uri(): No memory left\n");
 		return -1;
 	}
 
 	if (tag_len) {

 		len = tag - _h->body.s;
 		memcpy(_s->s, _h->body.s, len);
 		memcpy(_s->s + len, tag + tag_len, _h->body.len - len - tag_len);
 		_s->len = _h->body.len - tag_len;

 	} else {

 		memcpy(_s->s, _h->body.s, _h->body.len);
 		_s->len = _h->body.len;

 	}
 
 	return 0;
 }
 
 
 /*
  * Extract all information from a request 
  * and update a dialog structure
  */
 static inline int request2dlg(struct sip_msg* _m, dlg_t* _d)
 {
 	str contact, rtag, callid;
 

 	if (parse_headers(_m, HDR_EOH_F, 0) == -1) {

 		LOG(L_ERR, "request2dlg(): Error while parsing headers");
 		return -1;
 	}
 
 	if (get_contact_uri(_m, &contact) < 0) return -2;

 	if (contact.len) {
 		if (_d->rem_target.s) shm_free(_d->rem_target.s);
 		if (_d->dst_uri.s) {
 			shm_free(_d->dst_uri.s);
 			_d->dst_uri.s = 0;
 			_d->dst_uri.len = 0;
 		}
 		if (str_duplicate(&_d->rem_target, &contact) < 0) return -3;
 	}

 	
 	if (get_from_tag(_m, &rtag) < 0) goto err1;
 	if (rtag.len && str_duplicate(&_d->id.rem_tag, &rtag) < 0) goto err1;
 
 	if (get_callid(_m, &callid) < 0) goto err2;
 	if (callid.len && str_duplicate(&_d->id.call_id, &callid) < 0) goto err2;
 
 	if (get_cseq_value(_m, &_d->rem_seq.value) < 0) goto err3;
 	_d->rem_seq.is_set = 1;
 
 	if (get_dlg_uri(_m->from, &_d->rem_uri) < 0) goto err3;
 	if (get_dlg_uri(_m->to, &_d->loc_uri) < 0) goto err4;
 
 	if (get_route_set(_m, &_d->route_set, NORMAL_ORDER) < 0) goto err5;	
 
 	return 0;
  err5:

 	if (_d->loc_uri.s) shm_free(_d->loc_uri.s);

 	_d->loc_uri.s = 0;
 	_d->loc_uri.len = 0;
  err4:

 	if (_d->rem_uri.s) shm_free(_d->rem_uri.s);

 	_d->rem_uri.s = 0;
 	_d->rem_uri.len = 0;
  err3:

 	if (_d->id.call_id.s) shm_free(_d->id.call_id.s);

 	_d->id.call_id.s = 0;
 	_d->id.call_id.len = 0;
  err2:

 	if (_d->id.rem_tag.s) shm_free(_d->id.rem_tag.s);

 	_d->id.rem_tag.s = 0;
 	_d->id.rem_tag.len = 0;
  err1:

 	if (_d->rem_target.s) shm_free(_d->rem_target.s);

 	_d->rem_target.s = 0;
 	_d->rem_target.len = 0;
 	return -4;
 }
 
 
 /*
  * Establishing a new dialog, UAS side
  */

 int new_dlg_uas(struct sip_msg* _req, int _code, /*str* _tag,*/ dlg_t** _d)

 {
 	dlg_t* res;

 	str tag;

 	if (!_req || /*!_tag ||*/ !_d) {

 		LOG(L_ERR, "new_dlg_uas(): Invalid parameter value\n");
 		return -1;
 	}
 

 	if (_code > 299) {
 		DBG("new_dlg_uas(): Status code >= 300, no dialog created\n");

 	}
 

 	res = (dlg_t*)shm_malloc(sizeof(dlg_t));

 	if (res == 0) {
 		LOG(L_ERR, "new_dlg_uac(): No memory left\n");
 		return -3;
 	}
 	     /* Clear everything */
 	memset(res, 0, sizeof(dlg_t));	
 
 	if (request2dlg(_req, res) < 0) {
 		LOG(L_ERR, "new_dlg_uas(): Error while converting request to dialog\n");

 		free_dlg(res);

 		return -4;
 	}
 

 	if (_code > 100) {
 		tag.s = tm_tags;
 		tag.len = TOTAG_VALUE_LEN;
 		calc_crc_suffix(_req, tm_tag_suffix);
 		if (str_duplicate(&res->id.loc_tag, &tag) < 0) {
 			free_dlg(res);
 			return -5;
 		}

 	}

 	*_d = res;

 	if (_code < 100)
 		(*_d)->state = DLG_NEW;
 	else if (_code < 200)
 		(*_d)->state = DLG_EARLY;
 	else
 		(*_d)->state = DLG_CONFIRMED;
 

 	if (calculate_hooks(*_d) < 0) {
 		LOG(L_ERR, "new_dlg_uas(): Error while calculating hooks\n");

 		free_dlg(res);

 		return -6;
 	}
 

 	return 0;
 }
 

 /*
  * UAS side - update dialog state and to tag
  */
 int update_dlg_uas(dlg_t *_d, int _code, str* _tag)
 {
 	if (_d->state == DLG_CONFIRMED) {
 		LOG(L_ERR, "update_dlg_uas(): Dialog is already confirmed\n");
 		return -1;
 	} else if (_d->state == DLG_DESTROYED) {
 		LOG(L_ERR, "update_dlg_uas(): Dialog is already destroyed\n");
 		return -2;
 	}
 
 	if (_tag && _tag->s) {
 		if (_d->id.loc_tag.s) {
 			if ((_tag->len == _d->id.loc_tag.len)
 			&& (!memcmp(_tag->s, _d->id.loc_tag.s, _tag->len))) {
 				LOG(L_DBG, "update_dlg_uas(): Local tag is already set\n");
 			} else {
 				LOG(L_ERR, "update_dlg_uas(): ERROR: trying to rewrite local tag\n");
 				return -3;
 			}
 		} else {
 			if (str_duplicate(&_d->id.loc_tag, _tag) < 0) {
 				LOG(L_ERR, "update_dlg_uas(): Not enough memory\n");
 				return -4;
 			}
 		}
 	}
 
 	if ((100 < _code) && (_code < 200))
 		_d->state = DLG_EARLY;
 	else if (_code < 300)
 		_d->state = DLG_CONFIRMED;
 	else
 		_d->state = DLG_DESTROYED;
 
 	return 0;
 }
 

 /*
  * UAS side - update a dialog from a request
  */

 int dlg_request_uas(dlg_t* _d, struct sip_msg* _m, target_refresh_t is_target_refresh)

 {
 	str contact;
 	int cseq;
 
 	if (!_d || !_m) {
 		LOG(L_ERR, "dlg_request_uas(): Invalid parameter value\n");
 		return -1;
 	}
 
 	     /* We must check if the request is not out of order or retransmission
 	      * first, if so then we will not update anything
 	      */

 	if (parse_headers(_m, HDR_CSEQ_F, 0) == -1) {

 		LOG(L_ERR, "dlg_request_uas(): Error while parsing headers\n");
 		return -2;
 	}

 	if (get_cseq_value(_m, (unsigned int*)&cseq) < 0) return -3;

 	if (_d->rem_seq.is_set && (cseq <= _d->rem_seq.value)) return 0;
 
 	     /* Neither out of order nor retransmission -> update */
 	_d->rem_seq.value = cseq;
 	_d->rem_seq.is_set = 1;
 	
 	     /* We will als update remote target URI if the message 
 	      * is target refresher
 	      */

 	if (refresh_dialog_req(_m, is_target_refresh)) { /* target refresher */

 		if (parse_headers(_m, HDR_CONTACT_F, 0) == -1) {

 			LOG(L_ERR, "dlg_request_uas(): Error while parsing headers\n");
 			return -4;
 		}
 		
 		if (get_contact_uri(_m, &contact) < 0) return -5;
 		if (contact.len) {

 			if (_d->rem_target.s) shm_free(_d->rem_target.s);

 			if (_d->dst_uri.s) {
 				shm_free(_d->dst_uri.s);
 				_d->dst_uri.s = 0;
 				_d->dst_uri.len = 0;
 			}

 			if (str_duplicate(&_d->rem_target, &contact) < 0) return -6;
 		}

 
 		calculate_hooks(_d);
 		

 	}
 
 	return 0;
 }
 
 

 /*
  * Calculate length of the route set
  */
 int calculate_routeset_length(dlg_t* _d)
 {
 	int len;
 	rr_t* ptr;
 
 	len = 0;
 	ptr = _d->hooks.first_route;
 
 	if (ptr) {
 		len = ROUTE_PREFIX_LEN;
 		len += CRLF_LEN;
 	}
 
 	while(ptr) {
 		len += ptr->len;
 		ptr = ptr->next;
 		if (ptr) len += ROUTE_SEPARATOR_LEN;
 	} 
 
 	if (_d->hooks.last_route) {
 		len += ROUTE_SEPARATOR_LEN + 2; /* < > */
 		len += _d->hooks.last_route->len;
 	}
 
 	return len;
 }
 
 
 /*
  *
  * Print the route set
  */
 char* print_routeset(char* buf, dlg_t* _d)
 {
 	rr_t* ptr;
 
 	ptr = _d->hooks.first_route;
 

 	if (ptr || _d->hooks.last_route) {

 		memcpy(buf, ROUTE_PREFIX, ROUTE_PREFIX_LEN);
 		buf += ROUTE_PREFIX_LEN;
 	}
 
 	while(ptr) {
 		memcpy(buf, ptr->nameaddr.name.s, ptr->len);
 		buf += ptr->len;
 
 		ptr = ptr->next;
 		if (ptr) {
 			memcpy(buf, ROUTE_SEPARATOR, ROUTE_SEPARATOR_LEN);
 			buf += ROUTE_SEPARATOR_LEN;
 		}
 	} 
 
 	if (_d->hooks.last_route) {

 		if (_d->hooks.first_route) {
 			memcpy(buf, ROUTE_SEPARATOR, ROUTE_SEPARATOR_LEN);
 			buf += ROUTE_SEPARATOR_LEN;
 		}
 		memcpy(buf, "<", 1);
 		buf++;

 		memcpy(buf, _d->hooks.last_route->s, _d->hooks.last_route->len);
 		buf += _d->hooks.last_route->len;
 		*buf = '>';
 		buf++;
 	}
 

 	if (_d->hooks.first_route || _d->hooks.last_route) {

 		memcpy(buf, CRLF, CRLF_LEN);
 		buf += CRLF_LEN;
 	}
 
 	return buf;
 }
 
 

 /*
  * Destroy a dialog state
  */
 void free_dlg(dlg_t* _d)
 {
         if (!_d) return;
 

 	if (_d->id.call_id.s) shm_free(_d->id.call_id.s);
 	if (_d->id.rem_tag.s) shm_free(_d->id.rem_tag.s);
 	if (_d->id.loc_tag.s) shm_free(_d->id.loc_tag.s);

 	if (_d->loc_uri.s) shm_free(_d->loc_uri.s);
 	if (_d->rem_uri.s) shm_free(_d->rem_uri.s);
 	if (_d->rem_target.s) shm_free(_d->rem_target.s);

 	if (_d->dst_uri.s) shm_free(_d->dst_uri.s);

 
 	     /* Free all routes in the route set */

 	shm_free_rr(&_d->route_set);

 	shm_free(_d);

 }
 
 
 /*
  * Print a dialog structure, just for debugging
  */

 void print_dlg(FILE* out, dlg_t* _d)

 {

 	fprintf(out, "====dlg_t===\n");
 	fprintf(out, "id.call_id    : '%.*s'\n", _d->id.call_id.len, _d->id.call_id.s);
 	fprintf(out, "id.rem_tag    : '%.*s'\n", _d->id.rem_tag.len, _d->id.rem_tag.s);
 	fprintf(out, "id.loc_tag    : '%.*s'\n", _d->id.loc_tag.len, _d->id.loc_tag.s);
 	fprintf(out, "loc_seq.value : %d\n", _d->loc_seq.value);
 	fprintf(out, "loc_seq.is_set: %s\n", _d->loc_seq.is_set ? "YES" : "NO");
 	fprintf(out, "rem_seq.value : %d\n", _d->rem_seq.value);
 	fprintf(out, "rem_seq.is_set: %s\n", _d->rem_seq.is_set ? "YES" : "NO");
 	fprintf(out, "loc_uri       : '%.*s'\n", _d->loc_uri.len, _d->loc_uri.s);
 	fprintf(out, "rem_uri       : '%.*s'\n", _d->rem_uri.len, _d->rem_uri.s);
 	fprintf(out, "rem_target    : '%.*s'\n", _d->rem_target.len, _d->rem_target.s);

 	fprintf(out, "dst_uri       : '%.*s'\n", _d->dst_uri.len, _d->dst_uri.s);

 	fprintf(out, "secure:       : %d\n", _d->secure);
 	fprintf(out, "state         : ");

 	switch(_d->state) {

 	case DLG_NEW:       fprintf(out, "DLG_NEW\n");       break;
 	case DLG_EARLY:     fprintf(out, "DLG_EARLY\n");     break;
 	case DLG_CONFIRMED: fprintf(out, "DLG_CONFIRMED\n"); break;
 	case DLG_DESTROYED: fprintf(out, "DLG_DESTROYED\n"); break;
 	}
 	print_rr(out, _d->route_set);
 	if (_d->hooks.request_uri) 
 		fprintf(out, "hooks.request_uri: '%.*s'\n", _d->hooks.request_uri->len, _d->hooks.request_uri->s);
 	if (_d->hooks.next_hop) 
 		fprintf(out, "hooks.next_hop   : '%.*s'\n", _d->hooks.next_hop->len, _d->hooks.next_hop->s);
 	if (_d->hooks.first_route) 
 		fprintf(out, "hooks.first_route: '%.*s'\n", _d->hooks.first_route->len, _d->hooks.first_route->nameaddr.name.s);
 	if (_d->hooks.last_route)
 		fprintf(out, "hooks.last_route : '%.*s'\n", _d->hooks.last_route->len, _d->hooks.last_route->s);

 	fprintf(out, "====dlg_t====\n");

 }

 
 /*
  * set dialog's request uri and destination uri (optional)
  */
 int set_dlg_target(dlg_t* _d, str* _ruri, str* _duri) {
 
 	if (!_d || !_ruri) {
 		LOG(L_ERR, "set_dlg_target(): Invalid parameter value\n");
 		return -1;
 	}
 
 	if (_d->rem_target.s) shm_free(_d->rem_target.s);
 	if (_d->dst_uri.s) {
 		shm_free(_d->dst_uri.s);
 		_d->dst_uri.s = 0;
 		_d->dst_uri.len = 0;
 	}
 
 	if (str_duplicate(&_d->rem_target, _ruri)) return -1;
 	if (_duri && _duri->len) {
 		if (str_duplicate(&_d->dst_uri, _duri)) return -1;
 	}
 
 	if (calculate_hooks(_d)) {
 		LOG(L_ERR, "set_dlg_target(): Error while calculating hooks\n");
 		return -1;
 	}
 
 	return 0;
 }