/*
 * Copyright (C) 2006 Voice System SRL
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * Kamailio 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
 *
 * Kamailio 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */


/*!
 * \file
 * \brief Functions related to dialog handling
 * \ingroup dialog
 * Module: \ref dialog
 */

#include <string.h>
#include <time.h>

#include "../../core/trim.h"
#include "../../core/pvar.h"
#include "../../core/timer.h"
#include "../../core/counters.h"
#include "../../core/action.h"
#include "../../core/script_cb.h"
#include "../../core/pt.h"
#include "../../core/kemi.h"
#include "../../core/fmsg.h"
#include "../../core/parser/parse_from.h"
#include "../../core/parser/parse_cseq.h"
#include "../../core/parser/contact/parse_contact.h"
#include "../../core/parser/parse_rr.h"
#include "../../modules/tm/tm_load.h"
#include "../rr/api.h"
#include "dlg_hash.h"
#include "dlg_timer.h"
#include "dlg_cb.h"
#include "dlg_cseq.h"
#include "dlg_handlers.h"
#include "dlg_req_within.h"
#include "dlg_db_handler.h"
#include "dlg_profile.h"
#include "dlg_var.h"
#include "dlg_dmq.h"

static str rr_param;		   /*!< record-route parameter for matching */
static pv_spec_t *timeout_avp; /*!< AVP for timeout setting */
static int default_timeout;	   /*!< default dialog timeout */
static int seq_match_mode;	   /*!< dlg_match mode */
static int
		keep_proxy_rr; /*!< keep the proxy's record-route in both route-sets */
static int shutdown_done = 0; /*!< 1 when destroy_dlg_handlers was called */
extern int detect_spirals;
extern int dlg_timeout_noreset;
extern int initial_cbs_inscript;
extern int dlg_send_bye;
extern int dlg_event_rt[DLG_EVENTRT_MAX];
extern int dlg_wait_ack;
extern int dlg_enable_dmq;
extern int dlg_filter_mode;
extern int dlg_ctxiuid_mode;
int spiral_detected = -1;

extern struct rr_binds d_rrb; /*!< binding to record-routing module */


extern pv_elem_t *ruri_param_model; /*!< pv-string to get r-uri */

extern str dlg_event_callback;

static unsigned int CURR_DLG_LIFETIME = 0;	  /*!< current dialog lifetime */
static unsigned int CURR_DLG_STATUS = 0;	  /*!< current dialog state */
static unsigned int CURR_DLG_ID = 0xffffffff; /*!< current dialog id */


/*! size of the dialog record-route parameter */
#define RR_DLG_PARAM_SIZE (2 * 2 * sizeof(int) + 3 + MAX_DLG_RR_PARAM_NAME)
/*! separator inside the record-route paramter */
#define DLG_SEPARATOR '.'

/*! flags for dlg_ctxiuid */
#define DLG_CTXIUID_MODE_CANCEL 1

int dlg_set_tm_callbacks(
		tm_cell_t *t, sip_msg_t *req, dlg_cell_t *dlg, int mode);
int dlg_set_tm_waitack(tm_cell_t *t, dlg_cell_t *dlg);

/*!
 * \brief Initialize the dialog handlers
 * \param rr_param_p added record-route parameter
 * \param timeout_avp_p AVP for timeout setting
 * \param default_timeout_p default timeout
 * \param seq_match_mode_p matching mode
 * \param keep_proxy_rr_p keep proxy's record-route mode
 */
void init_dlg_handlers(char *rr_param_p, pv_spec_t *timeout_avp_p,
		int default_timeout_p, int seq_match_mode_p, int keep_proxy_rr_p)
{
	rr_param.s = rr_param_p;
	rr_param.len = strlen(rr_param.s);

	timeout_avp = timeout_avp_p;
	default_timeout = default_timeout_p;
	seq_match_mode = seq_match_mode_p;
	keep_proxy_rr = keep_proxy_rr_p;
}


/*!
 * \brief Shutdown operation of the module
 */
void destroy_dlg_handlers(void)
{
	shutdown_done = 1;
}


/*!
 * \brief Add record-route parameter for dialog tracking
 * \param req SIP request
 * \param entry dialog hash entry
 * \param id dialog hash id
 * \return 0 on success, -1 on failure
 */
static inline int add_dlg_rr_param(
		struct sip_msg *req, unsigned int entry, unsigned int id)
{
	static char buf[RR_DLG_PARAM_SIZE];
	str s;
	int n;
	char *p;

	s.s = p = buf;

	*(p++) = ';';
	memcpy(p, rr_param.s, rr_param.len);
	p += rr_param.len;
	*(p++) = '=';

	n = RR_DLG_PARAM_SIZE - (p - buf);
	if(int2reverse_hex(&p, &n, entry) == -1)
		return -1;

	*(p++) = DLG_SEPARATOR;

	n = RR_DLG_PARAM_SIZE - (p - buf);
	if(int2reverse_hex(&p, &n, id) == -1)
		return -1;

	s.len = p - buf;

	if(d_rrb.add_rr_param(req, &s) < 0) {
		LM_ERR("failed to add rr param\n");
		return -1;
	}

	return 0;
}


/*!
 * \brief Parse SIP message and populate leg informations
 *
 * Parse SIP message and populate leg informations.
 * \param dlg the dialog to add cseq, contact & record_route
 * \param msg sip message
 * \param t transaction
 * \param leg type of the call leg
 * \param tag SIP To tag
 * \return 0 on success, -1 on failure
 * \note for a request: get record route in normal order, for a reply get
 * in reverse order, skipping the ones from the request and the proxies' own
 */
int populate_leg_info(struct dlg_cell *dlg, struct sip_msg *msg, struct cell *t,
		unsigned int leg, str *tag)
{
	unsigned int skip_recs, own_rr = 0;
	str cseq;
	str contact;
	str rr_set;

	if(parse_headers(msg, HDR_EOH_F, 0) < 0) {
		LM_ERR("failed to parse headers\n");
		goto error0;
	}

	dlg->bind_addr[leg] = msg->rcv.bind_address;

	/* extract the cseq number as string */
	if(leg == DLG_CALLER_LEG) {
		if((!msg->cseq && (parse_headers(msg, HDR_CSEQ_F, 0) < 0 || !msg->cseq))
				|| !msg->cseq->parsed) {
			LM_ERR("bad sip message or missing CSeq hdr\n");
			goto error0;
		}
		cseq = (get_cseq(msg))->number;
	} else {
		/* use the same as in request */
		cseq = dlg->cseq[DLG_CALLEE_LEG];
	}
	if((leg == DLG_CALLER_LEG) && (cseq.s == NULL || cseq.len <= 0)) {
		LM_DBG("empty CSeq number (leg: %d)\n", leg);
	}

	/* extract the contact address */
	if(!msg->contact
			&& (parse_headers(msg, HDR_CONTACT_F, 0) < 0 || !msg->contact)) {
		LM_ERR("bad sip message or missing Contact hdr\n");
		goto error0;
	}
	if(parse_contact(msg->contact) < 0
			|| ((contact_body_t *)msg->contact->parsed)->contacts == NULL
			|| ((contact_body_t *)msg->contact->parsed)->contacts->next
					   != NULL) {
		LM_ERR("bad Contact HDR\n");
		goto error0;
	}
	contact = ((contact_body_t *)msg->contact->parsed)->contacts->uri;
	if(contact.s == NULL || contact.len <= 0) {
		LM_DBG("empty contact uri (leg: %d)\n", leg);
	}

	/* extract the record-route addresses */
	if(leg == DLG_CALLER_LEG) {
		skip_recs = 0;
	} else {
		/* was the 200 OK received or local generated */
		own_rr = ((t->relayed_reply_branch >= 0) ? (
						  (t->uac[t->relayed_reply_branch].flags
								  & TM_UAC_FLAG_R2)
								  ? 2
								  : ((t->uac[t->relayed_reply_branch].flags
											 & TM_UAC_FLAG_RR)
												  ? 1
												  : 0))
												 : 0);
		skip_recs = dlg->from_rr_nb + ((keep_proxy_rr & 1) > 0 ? 0 : own_rr);
	}

	if(msg->record_route) {
		if(print_rr_body(msg->record_route, &rr_set, leg, &skip_recs) != 0) {
			LM_ERR("failed to print route records \n");
			goto error0;
		}
	} else {
		rr_set.s = 0;
		rr_set.len = 0;
	}

	if(leg == DLG_CALLER_LEG)
		dlg->from_rr_nb = skip_recs;

	LM_DBG("leg(%d) route_set [%.*s], contact [%.*s], cseq [%.*s]"
		   " and bind_addr [%.*s]\n",
			leg, rr_set.len, ZSW(rr_set.s), contact.len, ZSW(contact.s),
			cseq.len, ZSW(cseq.s), msg->rcv.bind_address->sock_str.len,
			ZSW(msg->rcv.bind_address->sock_str.s));

	if(dlg_set_leg_info(dlg, tag, &rr_set, &contact, &cseq, leg) != 0) {
		LM_ERR("dlg_set_leg_info failed (leg %d)\n", leg);
		if(rr_set.s)
			pkg_free(rr_set.s);
		goto error0;
	}

	if(rr_set.s)
		pkg_free(rr_set.s);

	if((keep_proxy_rr & 2) > 0 && leg == DLG_CALLEE_LEG && msg->record_route
			&& own_rr > 0) {
		/* skip_recs contains the number of RR's for the callee */
		skip_recs -= own_rr;
		/* Add local RR's to caller's routeset */
		if(print_rr_body(msg->record_route, &rr_set, DLG_CALLER_LEG, &skip_recs)
				!= 0) {
			LM_ERR("failed to print route records \n");
			goto error0;
		}
		LM_DBG("updating caller route_set %.*s\n", rr_set.len, rr_set.s);
		if(dlg_update_rr_set(dlg, DLG_CALLER_LEG, &rr_set) != 0) {
			LM_ERR("dlg_update_rr_set failed\n");
			if(rr_set.s)
				pkg_free(rr_set.s);
			goto error0;
		}
		if(rr_set.s)
			pkg_free(rr_set.s);
	}

	return 0;
error0:
	return -1;
}

/*!
 * \brief Clone dialog internal unique id to shared memory
 */
dlg_iuid_t *dlg_get_iuid_shm_clone(dlg_cell_t *dlg)
{
	dlg_iuid_t *iuid = NULL;

	if(dlg == NULL)
		return NULL;

	iuid = (dlg_iuid_t *)shm_malloc(sizeof(dlg_iuid_t));
	if(iuid == NULL) {
		LM_ERR("failed to clone dialog iuid\n");
		return NULL;
	}

	memset(iuid, 0, sizeof(dlg_iuid_t));
	iuid->h_entry = dlg->h_entry;
	iuid->h_id = dlg->h_id;

	return iuid;
}


/*!
 * \brief Free dialog internal unique id stored in shared memory
 */
void dlg_iuid_sfree(void *iuid)
{
	if(iuid) {
		LM_DBG("freeing dlg iuid [%u:%u] (%p)\n", ((dlg_iuid_t *)iuid)->h_entry,
				((dlg_iuid_t *)iuid)->h_id, iuid);
		shm_free(iuid);
	}
}


/*!
 * \brief Function that executes BYE reply callbacks
 * \param t transaction, unused
 * \param type type of the callback, should be TMCB_RESPONSE_FWDED
 * \param params saved dialog structure inside the callback
 */
static void dlg_terminated_confirmed(
		tm_cell_t *t, int type, struct tmcb_params *params)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	if(!params || !params->req || !params->param) {
		LM_ERR("invalid parameters!\n");
		return;
	}

	iuid = (dlg_iuid_t *)*params->param;
	if(iuid == NULL)
		return;

	dlg = dlg_get_by_iuid(iuid);

	if(dlg == NULL) {
		LM_ERR("failed to get dialog from params!\n");
		return;
	}
	/* dialog termination confirmed (BYE reply) */
	run_dlg_callbacks(DLGCB_TERMINATED_CONFIRMED, dlg, params->req, params->rpl,
			DLG_DIR_UPSTREAM, 0);
	dlg_release(dlg);
}

/*!
 * \brief Execute callback for the BYE request and register callback for the BYE reply
 * \param req request message
 * \param dlg corresponding dialog
 * \param dir message direction
 */
static void dlg_terminated(sip_msg_t *req, dlg_cell_t *dlg, unsigned int dir)
{
	dlg_iuid_t *iuid = NULL;

	if(!req) {
		LM_ERR("request is empty!");
		return;
	}

	if(!dlg) {
		LM_ERR("dialog is empty!");
		return;
	}

	/* dialog terminated (BYE) */
	run_dlg_callbacks(DLGCB_TERMINATED, dlg, req, NULL, dir, 0);

	iuid = dlg_get_iuid_shm_clone(dlg);
	if(iuid == NULL)
		return;

	/* register callback for the corresponding reply */
	if(d_tmb.register_tmcb(req, 0, TMCB_RESPONSE_OUT, dlg_terminated_confirmed,
			   (void *)iuid, dlg_iuid_sfree)
			<= 0) {
		LM_ERR("cannot register response callback for BYE request\n");
		return;
	}
}

/*!
 * \brief Function that is registered as TM callback and called on T destroy
 *
 * - happens when wait_ack==1
 *
 */
static void dlg_ontdestroy(struct cell *t, int type, struct tmcb_params *param)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	iuid = (dlg_iuid_t *)(*param->param);
	dlg = dlg_get_by_iuid(iuid);
	if(dlg == 0)
		return;
	/* 1 for callback and 1 for dlg lookup */
	dlg_unref(dlg, 2);
}

/*!
 * \brief Function that is registered as TM callback and called on replies
 *
 * Function that is registered as TM callback and called on replies. It
 * parses the reply and set the appropriate event. This is then used to
 * update the dialog state, run eventual dialog callbacks and save or
 * update the necessary informations about the dialog.
 * \see next_state_dlg
 * \param t transaction, unused
 * \param type type of the entered callback
 * \param param saved dialog structure in the callback
 */
static void dlg_onreply(struct cell *t, int type, struct tmcb_params *param)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;
	int new_state, old_state, unref, event;
	str tag;
	sip_msg_t *req = param->req;
	sip_msg_t *rpl = param->rpl;

	if(shutdown_done)
		return;
	iuid = (dlg_iuid_t *)(*param->param);
	dlg = dlg_get_by_iuid(iuid);
	if(dlg == 0)
		return;

	if(rpl != FAKED_REPLY) {
		if(parse_headers(rpl, HDR_EOH_F, 0) < 0) {
			LM_ERR("failed to parse the reply headers\n");
			goto done_early;
		}
	}

	unref = 0;
	if(type & (TMCB_RESPONSE_IN | TMCB_ON_FAILURE)) {
		/* Set the dialog context so it is available in onreply_route and failure_route*/
		set_current_dialog(req, dlg);
		dlg_set_ctx_iuid(dlg);
		goto done_early;
	}

	if(type == TMCB_RESPONSE_FWDED) {
		/* The state does not change, but the msg is mutable in this callback*/
		run_dlg_callbacks(
				DLGCB_RESPONSE_FWDED, dlg, req, rpl, DLG_DIR_UPSTREAM, 0);
		goto done_early;
	}

	if(type == TMCB_DESTROY)
		event = DLG_EVENT_TDEL;
	else if(param->code < 200)
		event = DLG_EVENT_RPL1xx;
	else if(param->code < 300)
		event = DLG_EVENT_RPL2xx;
	else
		event = DLG_EVENT_RPL3xx;

	next_state_dlg(dlg, event, &old_state, &new_state, &unref);
	if(new_state == DLG_STATE_DELETED && old_state != DLG_STATE_DELETED) {
		/* set end time */
		dlg->end_ts = (unsigned int)(time(0));
	}
	if(dlg_run_event_route(
			   dlg, (rpl == FAKED_REPLY) ? NULL : rpl, old_state, new_state)
			< 0) {
		/* dialog is gone */
		return;
	}

	if(new_state == DLG_STATE_EARLY) {
		run_dlg_callbacks(DLGCB_EARLY, dlg, req, rpl, DLG_DIR_UPSTREAM, 0);
		if(old_state != DLG_STATE_EARLY)
			if_update_stat(dlg_enable_stats, early_dlgs, 1);
		goto done;
	}

	if(new_state == DLG_STATE_CONFIRMED_NA
			&& old_state != DLG_STATE_CONFIRMED_NA
			&& old_state != DLG_STATE_CONFIRMED) {
		LM_DBG("dialog %p confirmed (ACK pending)\n", dlg);

		if(rpl != FAKED_REPLY) {
			/* get to tag*/
			if(!rpl->to
					&& ((parse_headers(rpl, HDR_TO_F, 0) < 0) || !rpl->to)) {
				LM_ERR("bad reply or missing TO hdr :-/\n");
				tag.s = 0;
				tag.len = 0;
			} else {
				tag = get_to(rpl)->tag_value;
				if(tag.s == 0 || tag.len == 0) {
					LM_ERR("missing TAG param in TO hdr :-/\n");
					tag.s = 0;
					tag.len = 0;
				}
			}

			/* save callee's tag, cseq, contact and record route*/
			if(populate_leg_info(dlg, rpl, t, DLG_CALLEE_LEG, &tag) != 0) {
				LM_ERR("could not add further info to the dialog\n");
			}
		} else {
			LM_ERR("Faked reply!\n");
		}

		/* set start time */
		dlg->start_ts = (unsigned int)(time(0));

		/* save the settings to the database,
		 * if realtime saving mode configured- save dialog now
		 * else: the next time the timer will fire the update*/
		dlg->dflags |= DLG_FLAG_NEW;
		if(dlg_db_mode == DB_MODE_REALTIME)
			update_dialog_dbinfo(dlg);

		if(0 != insert_dlg_timer(&dlg->tl, dlg->lifetime)) {
			LM_CRIT("Unable to insert dlg %p [%u:%u] on event %d [%d->%d] "
					"with clid '%.*s' and tags '%.*s' '%.*s'\n",
					dlg, dlg->h_entry, dlg->h_id, event, old_state, new_state,
					dlg->callid.len, dlg->callid.s,
					dlg->tag[DLG_CALLER_LEG].len, dlg->tag[DLG_CALLER_LEG].s,
					dlg->tag[DLG_CALLEE_LEG].len, dlg->tag[DLG_CALLEE_LEG].s);
		} else {
			/* dialog pointer inserted in timer list */
			dlg_ref(dlg, 1);
		}

		/* dialog confirmed (ACK pending) */
		run_dlg_callbacks(
				DLGCB_CONFIRMED_NA, dlg, req, rpl, DLG_DIR_UPSTREAM, 0);

		if(old_state == DLG_STATE_EARLY)
			if_update_stat(dlg_enable_stats, early_dlgs, -1);

		if(unref)
			dlg_unref(dlg, unref);
		if_update_stat(dlg_enable_stats, active_dlgs, 1);
		goto done;
	}

	if(new_state == DLG_STATE_DELETED
			&& (old_state == DLG_STATE_UNCONFIRMED
					|| old_state == DLG_STATE_EARLY)) {
		LM_DBG("dialog %p failed (negative reply)\n", dlg);
		/* dialog setup not completed (3456XX) */
		run_dlg_callbacks(DLGCB_FAILED, dlg, req, rpl, DLG_DIR_UPSTREAM, 0);
		if(dlg_wait_ack == 1)
			dlg_set_tm_waitack(t, dlg);
		/* do unref */
		if(unref)
			dlg_unref(dlg, unref);
		if(old_state == DLG_STATE_EARLY)
			if_update_stat(dlg_enable_stats, early_dlgs, -1);

		if_update_stat(dlg_enable_stats, failed_dlgs, 1);

		goto done;
	}

	if(unref)
		dlg_unref(dlg, unref);

done:
	if(dlg_enable_dmq && (dlg->iflags & DLG_IFLAG_DMQ_SYNC)
			&& new_state > old_state) {
		dlg_dmq_replicate_action(DLG_DMQ_STATE, dlg, 0, 0);
	}

done_early:
	/* unref due to dlg_get_by_iuid() */
	dlg_release(dlg);
	return;
}


/*!
 * \brief Helper function that run dialog callbacks on forwarded requests
 * \see dlg_seq_up_onreply
 * \see dlg_seq_down_onreply
 * \param t transaction, unused
 * \param type type of the callback, should be TMCB_RESPONSE_FWDED
 * \param param saved dialog structure inside the callback
 * \param direction direction of the request
 */
static void dlg_seq_onreply_helper(struct cell *t, int type,
		struct tmcb_params *param, const int direction)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	if(shutdown_done)
		return;
	iuid = (dlg_iuid_t *)(*param->param);
	dlg = dlg_get_by_iuid(iuid);
	if(dlg == 0)
		return;

	if(type == TMCB_RESPONSE_FWDED) {
		run_dlg_callbacks(DLGCB_RESPONSE_WITHIN, dlg, param->req, param->rpl,
				direction, 0);
	}
	dlg_release(dlg);

	return;
}


/*!
 * \brief Run dialog callbacks on forwarded requests in upstream direction
 * \see dlg_seq_onreply_helper
 * \param t transaction, unused
 * \param type type of the callback, should be TMCB_RESPONSE_FWDED
 * \param param saved dialog structure inside the callback
 */
static void dlg_seq_up_onreply(
		struct cell *t, int type, struct tmcb_params *param)
{
	dlg_seq_onreply_helper(t, type, param, DLG_DIR_UPSTREAM);
}


/*!
 * \brief Run dialog callbacks on forwarded requests in downstream direction
 * \see dlg_seq_onreply_helper
 * \param t transaction, unused
 * \param type type of the callback, should be TMCB_RESPONSE_FWDED
 * \param param saved dialog structure inside the callback
 */
static void dlg_seq_down_onreply(
		struct cell *t, int type, struct tmcb_params *param)
{
	dlg_seq_onreply_helper(t, type, param, DLG_DIR_DOWNSTREAM);
}


/*!
 * \brief Return the timeout for a dialog
 * \param req SIP message
 * \return value from timeout AVP if present or default timeout
 */
inline static int get_dlg_timeout(struct sip_msg *req)
{
	pv_value_t pv_val;

	if(timeout_avp) {
		if(pv_get_spec_value(req, timeout_avp, &pv_val) == 0) {
			if(pv_val.flags & PV_VAL_INT) {
				if(pv_val.ri > 0) {
					return pv_val.ri;
				} else {
					LM_DBG("invalid AVP value\n");
				}
			} else {
				LM_DBG("invalid AVP type\n");
			}
		}
		LM_DBG("unable to get valid AVP value, using default timeout\n");
	} else {
		LM_DBG("using default timeout\n");
	}
	return default_timeout;
}

/*!
 * \brief Helper function to get the necessary content from SIP message
 * \param req SIP request
 * \param callid found callid
 * \param ftag found from tag
 * \param ttag found to tag
 * \param with_ttag flag set if to tag must be found for success
 * \return 0 on success, -1 on failure
 */
static inline int pre_match_parse(
		struct sip_msg *req, str *callid, str *ftag, str *ttag, int with_ttag)
{
	if(parse_headers(req, HDR_CALLID_F | HDR_TO_F, 0) < 0 || !req->callid
			|| !req->to) {
		LM_ERR("bad request or missing CALLID/TO hdr :-/\n");
		return -1;
	}

	if(get_to(req)->tag_value.len == 0) {
		if(with_ttag == 1) {
			/* out of dialog request with preloaded Route headers; ignore. */
			return -1;
		} else {
			ttag->s = NULL;
			ttag->len = 0;
		}
	} else {
		*ttag = get_to(req)->tag_value;
	}

	if(parse_from_header(req) < 0 || get_from(req)->tag_value.len == 0) {
		LM_ERR("failed to get From header\n");
		return -1;
	}

	/* callid */
	*callid = req->callid->body;
	trim(callid);
	/* from tag */
	*ftag = get_from(req)->tag_value;
	return 0;
}

/*!
 * \brief Sync dialog from tm callback (another wrapper)
 * \param t transaction, unused
 * \param type type of the entered callback
 * \param param saved dialog structure in the callback
 */
static void dlg_on_send(struct cell *t, int type, struct tmcb_params *param)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	LM_DBG("dialog_on_send CB\n");
	iuid = (dlg_iuid_t *)(*param->param);
	if(iuid == NULL)
		return;

	dlg = dlg_get_by_iuid(iuid);
	if(dlg == NULL)
		return;

	/* sync over dmq */
	if(dlg_enable_dmq) {
		dlg_dmq_replicate_action(DLG_DMQ_UPDATE, dlg, 1, 0);
	}

	/* unref by 2: 1 set when adding in tm cb, 1 set by dlg_get_by_iuid() */
	dlg_unref(dlg, 1);
}


/*!
 * \brief Function that is registered as TM callback and called on requests
 * \see dlg_new_dialog
 * \param t transaction, used to created the dialog
 * \param type type of the entered callback
 * \param param saved dialog structure in the callback
 */
void dlg_onreq(struct cell *t, int type, struct tmcb_params *param)
{
	sip_msg_t *req = param->req;
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	if(req->first_line.u.request.method_value == METHOD_BYE) {
		_dlg_ctx.t = 1;
		return;
	}

	if(req->first_line.u.request.method_value != METHOD_INVITE)
		return;

	dlg = dlg_get_ctx_dialog();

	if(dlg != NULL) {
		if(!initial_cbs_inscript) {
			if(spiral_detected == 1)
				run_dlg_callbacks(
						DLGCB_SPIRALED, dlg, req, NULL, DLG_DIR_DOWNSTREAM, 0);
			else if(spiral_detected == 0)
				run_create_callbacks(dlg, req);
		}

		LM_DBG("dialog added to tm callbacks\n");
		dlg_set_tm_callbacks(t, req, dlg, spiral_detected);
		_dlg_ctx.t = 1;
		dlg_release(dlg);
	}

	if(dlg_enable_dmq) {
		iuid = dlg_get_iuid_shm_clone(dlg);
		if(iuid == NULL) {
			LM_ERR("failed to create dialog unique id clone\n");
		} else {
			/* register callback for when the request is sent */
			if(d_tmb.register_tmcb(req, t, TMCB_REQUEST_FWDED, dlg_on_send,
					   (void *)iuid, dlg_iuid_sfree)
					< 0) {
				LM_ERR("failed to register TMCB_REQUEST_FWDED\n");
				shm_free(iuid);
			}
		}
	}
}


/*!
 * \brief Unreference a new dialog, helper function for dlg_onreq
 * \see dlg_onreq
 * \param dialog unreferenced dialog
 */
#if 0
static void unref_new_dialog(void *iuid)
{
	struct tmcb_params p;

	memset(&p, 0, sizeof(struct tmcb_params));
	p.param = (void*)&iuid;
	dlg_onreply(0, TMCB_DESTROY, &p);
}
#endif


/*!
 * \brief Create a new dialog from a sip message
 *
 * Create a new dialog from a SIP message, register a callback
 * to keep track of the dialog with help of the tm module.
 * This function is either called from the request callback, or
 * from the dlg_manage function in the configuration script.
 * \see dlg_onreq
 * \see w_dlg_manage
 * \param req SIP message
 * \param t transaction
 * \param run_initial_cbs if set zero, initial callbacks are not executed
 * \return 0 on success, -1 on failure
 */
int dlg_new_dialog(sip_msg_t *req, struct cell *t, const int run_initial_cbs)
{
	dlg_cell_t *dlg;
	str s;
	str callid;
	str ftag;
	str ttag;
	str req_uri;
	unsigned int dir;

	dlg = dlg_get_ctx_dialog();
	if(dlg != NULL) {
		dlg_release(dlg);
		return -1;
	}

	if(req->first_line.u.request.method_value != METHOD_INVITE)
		return -1;

	if(parse_headers(req, HDR_EOH_F, 0) < 0) {
		LM_ERR("failed to parse the request headers\n");
		return -1;
	}

	if(pre_match_parse(req, &callid, &ftag, &ttag, 0) < 0) {
		LM_WARN("pre-matching failed\n");
		return -1;
	}

	if(ttag.s != 0 && ttag.len != 0)
		return -1;

	if(pv_printf_s(req, ruri_param_model, &req_uri) < 0) {
		LM_ERR("error - cannot print the r-uri format\n");
		return -1;
	}
	trim(&req_uri);

	dir = DLG_DIR_NONE;
	/* search dialog by SIP attributes
	 * - hash table slot is left locked  */
	dlg = dlg_search(&callid, &ftag, &ttag, &dir);
	if(dlg) {
		if(detect_spirals) {
			if(spiral_detected == 1) {
				dlg_hash_release(&callid);
				return 0;
			}

			if(dlg->state != DLG_STATE_DELETED) {
				LM_DBG("Callid '%.*s' found, must be a spiraled request\n",
						callid.len, callid.s);
				spiral_detected = 1;

				if(run_initial_cbs)
					run_dlg_callbacks(DLGCB_SPIRALED, dlg, req, NULL,
							DLG_DIR_DOWNSTREAM, 0);
				/* set ctx dlg id shortcuts */
				_dlg_ctx.iuid.h_entry = dlg->h_entry;
				_dlg_ctx.iuid.h_id = dlg->h_id;
				/* search_dlg() has incremented the ref count by 1 */
				dlg_release(dlg);
				dlg_hash_release(&callid);
				return 0;
			}
			dlg_release(dlg);
		}
	}
	spiral_detected = 0;

	dlg = build_new_dlg(&callid /*callid*/, &(get_from(req)->uri) /*from uri*/,
			&(get_to(req)->uri) /*to uri*/, &ftag /*from_tag*/,
			&req_uri /*r-uri*/);

	if(dlg == 0) {
		dlg_hash_release(&callid);
		LM_ERR("failed to create new dialog\n");
		return -1;
	}
	// Store link to Transaction
	dlg->t = t;

	/* save caller's tag, cseq, contact and record route*/
	if(populate_leg_info(
			   dlg, req, t, DLG_CALLER_LEG, &(get_from(req)->tag_value))
			!= 0) {
		dlg_hash_release(&callid);
		LM_ERR("could not add further info to the dialog\n");
		shm_free(dlg);
		return -1;
	}

	/* Populate initial varlist: */
	dlg->vars = get_local_varlist_pointer(req, 1);

	/* after dlg_search() slot was kept locked */
	link_dlg(dlg, 0, 1);
	/* unlock after dlg_search() */
	dlg_hash_release(&callid);

	dlg->lifetime = get_dlg_timeout(req);
	s.s = _dlg_ctx.to_route_name;
	s.len = strlen(s.s);
	dlg_set_toroute(dlg, &s);
	dlg->sflags |= _dlg_ctx.flags;
	dlg->iflags |= _dlg_ctx.iflags;

	if(dlg_send_bye != 0 || _dlg_ctx.to_bye != 0)
		dlg->iflags |= DLG_IFLAG_TIMEOUTBYE;

	if(run_initial_cbs)
		run_create_callbacks(dlg, req);

	/* first INVITE seen (dialog created, unconfirmed) */
	if(seq_match_mode != SEQ_MATCH_NO_ID
			&& add_dlg_rr_param(req, dlg->h_entry, dlg->h_id) < 0) {
		LM_ERR("failed to add RR param\n");
		goto error;
	}

	if_update_stat(dlg_enable_stats, processed_dlgs, 1);

	_dlg_ctx.cpid = my_pid();
	_dlg_ctx.iuid.h_entry = dlg->h_entry;
	_dlg_ctx.iuid.h_id = dlg->h_id;
	set_current_dialog(req, dlg);

	return 0;

error:
	if(!spiral_detected)
		dlg_unref(dlg, 1); // undo ref regarding linking
	return -1;
}


/*!
 * \brief add dlg structure to tm callbacks
 * \param t current transaction
 * \param req current sip request
 * \param dlg current dialog
 * \param smode if the sip request was spiraled
 * \return 0 on success, -1 on failure
 */
int dlg_set_tm_callbacks(
		tm_cell_t *t, sip_msg_t *req, dlg_cell_t *dlg, int smode)
{
	dlg_iuid_t *iuid = NULL;
	if(t == NULL)
		return -1;

	if(smode == 0) {
		iuid = dlg_get_iuid_shm_clone(dlg);
		if(iuid == NULL) {
			LM_ERR("failed to create dialog unique id clone\n");
			goto error;
		}
		if(d_tmb.register_tmcb(req, t,
				   TMCB_RESPONSE_IN | TMCB_RESPONSE_READY | TMCB_RESPONSE_FWDED
						   | TMCB_ON_FAILURE,
				   dlg_onreply, (void *)iuid, dlg_iuid_sfree)
				< 0) {
			LM_ERR("failed to register TMCB\n");
			goto error;
		}
	}

	dlg->dflags |= DLG_FLAG_TM;

	return 0;
error:
	dlg_iuid_sfree(iuid);
	return -1;
}

/*!
 * \brief add dlg structure to tm callbacks to wait for negative ACK
 * \param t current transaction
 * \param dlg current dialog
 * \return 0 on success, -1 on failure
 */
int dlg_set_tm_waitack(tm_cell_t *t, dlg_cell_t *dlg)
{
	dlg_iuid_t *iuid = NULL;
	if(t == NULL)
		return -1;

	LM_DBG("registering TMCB to wait for negative ACK\n");
	iuid = dlg_get_iuid_shm_clone(dlg);
	if(iuid == NULL) {
		LM_ERR("failed to create dialog unique id clone\n");
		goto error;
	}
	dlg_ref(dlg, 1);
	if(d_tmb.register_tmcb(NULL, t, TMCB_DESTROY, dlg_ontdestroy, (void *)iuid,
			   dlg_iuid_sfree)
			< 0) {
		LM_ERR("failed to register TMCB to wait for negative ACK\n");
		dlg_unref(dlg, 1);
		goto error;
	}

	return 0;
error:
	dlg_iuid_sfree(iuid);
	return -1;
}

/*!
 * \brief Parse the record-route parameter, to get dialog information back
 * \param p start of parameter string
 * \param end end of parameter string
 * \param h_entry found dialog hash entry
 * \param h_id found dialog hash id
 * \return 0 on success, -1 on failure
 */
static inline int parse_dlg_rr_param(
		char *p, char *end, int *h_entry, int *h_id)
{
	char *s;

	/* sanity checks */
	if(!p) {
		LM_ERR("NULL start of parameter string");
		return -1;
	}

	if(!end) {
		LM_ERR("NULL end of parameter string");
		return -1;
	}

	if(!h_entry) {
		LM_ERR("NULL h_entry");
		return -1;
	}

	if(!h_id) {
		LM_ERR("NULL h_id");
		return -1;
	}

	for(s = p; p < end && *p != DLG_SEPARATOR; p++)
		;

	if(*p != DLG_SEPARATOR) {
		LM_ERR("malformed rr param '%.*s'\n", (int)(long)(end - s), s);
		return -1;
	}

	if(reverse_hex2int(s, p - s, (unsigned int *)h_entry) < 0) {
		LM_ERR("invalid hash entry '%.*s'\n", (int)(long)(p - s), s);
		return -1;
	}

	if(reverse_hex2int(p + 1, end - (p + 1), (unsigned int *)h_id) < 0) {
		LM_ERR("invalid hash id '%.*s'\n", (int)(long)(end - (p + 1)), p + 1);
		return -1;
	}

	return 0;
}


/*!
 * \brief Update the saved Contact information in dialog from SIP message
 * \param dlg updated dialog
 * \param req SIP request
 * \param dir direction of request, must DLG_DIR_UPSTREAM or DLG_DIR_DOWNSTREAM
 * \return 0 on success, -1 on failure
 */
static inline int dlg_refresh_contacts(
		struct dlg_cell *dlg, struct sip_msg *req, unsigned int dir)
{
	str contact;

	if(req->first_line.type == SIP_REPLY)
		return 0;
	if(req->first_line.u.request.method_value != METHOD_INVITE)
		return 0;

	/* extract the contact address */
	if(!req->contact
			&& (parse_headers(req, HDR_CONTACT_F, 0) < 0 || !req->contact)) {
		LM_ERR("bad sip message or missing Contact hdr\n");
		return -1;
	}
	if(parse_contact(req->contact) < 0
			|| ((contact_body_t *)req->contact->parsed)->contacts == NULL
			|| ((contact_body_t *)req->contact->parsed)->contacts->next
					   != NULL) {
		LM_ERR("bad Contact HDR\n");
		return -1;
	}
	contact = ((contact_body_t *)req->contact->parsed)->contacts->uri;

	if(dir == DLG_DIR_UPSTREAM) {
		return dlg_update_contact(dlg, DLG_CALLEE_LEG, &contact);
	} else if(dir == DLG_DIR_DOWNSTREAM) {
		return dlg_update_contact(dlg, DLG_CALLER_LEG, &contact);
	} else {
		LM_CRIT("dir is not set!\n");
		return -1;
	}
}


/*!
 * \brief Update the saved CSEQ information in dialog from SIP message
 * \param dlg updated dialog
 * \param req SIP request
 * \param dir direction of request, must DLG_DIR_UPSTREAM or DLG_DIR_DOWNSTREAM
 * \return 0 on success, -1 on failure
 */
static inline int update_cseqs(
		struct dlg_cell *dlg, struct sip_msg *req, unsigned int dir)
{
	if((!req->cseq && parse_headers(req, HDR_CSEQ_F, 0) < 0) || !req->cseq
			|| !req->cseq->parsed) {
		LM_ERR("bad sip message or missing CSeq hdr :-/\n");
		return -1;
	}

	if(dir == DLG_DIR_UPSTREAM) {
		return dlg_update_cseq(dlg, DLG_CALLEE_LEG, &((get_cseq(req))->number));
	} else if(dir == DLG_DIR_DOWNSTREAM) {
		return dlg_update_cseq(dlg, DLG_CALLER_LEG, &((get_cseq(req))->number));
	} else {
		LM_CRIT("dir is not set!\n");
		return -1;
	}
}

/*!
 * \brief Unreference a dialog from tm callback (another wrapper)
 * \param t transaction, unused
 * \param type type of the entered callback
 * \param param saved dialog structure in the callback
 */
static void unref_dlg_from_cb(
		struct cell *t, int type, struct tmcb_params *param)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;

	iuid = (dlg_iuid_t *)(*param->param);
	if(iuid == NULL)
		return;

	dlg = dlg_get_by_iuid(iuid);
	if(dlg == NULL)
		return;
	/* unref by 2: 1 set when adding in tm cb, 1 sent by dlg_get_by_iuid() */
	dlg_unref(dlg, 2);
}

/*!
 *
 */
dlg_cell_t *dlg_lookup_msg_dialog(sip_msg_t *msg, unsigned int *dir)
{
	dlg_cell_t *dlg = NULL;
	str callid;
	str ftag;
	str ttag;
	unsigned int vdir;

	/* Retrieve the current dialog */
	dlg = dlg_get_ctx_dialog();
	if(dlg != NULL) {
		if(dir) {
			if(pre_match_parse(msg, &callid, &ftag, &ttag, 0) < 0) {
				dlg_release(dlg);
				return NULL;
			}
			if(dlg->tag[DLG_CALLER_LEG].len == ftag.len
					&& strncmp(dlg->tag[DLG_CALLER_LEG].s, ftag.s, ftag.len)
							   == 0
					&& strncmp(dlg->callid.s, callid.s, callid.len) == 0) {
				*dir = DLG_DIR_DOWNSTREAM;
			} else {
				if(ttag.len > 0 && dlg->tag[DLG_CALLER_LEG].len == ttag.len
						&& strncmp(dlg->tag[DLG_CALLER_LEG].s, ttag.s, ttag.len)
								   == 0
						&& strncmp(dlg->callid.s, callid.s, callid.len) == 0) {
					*dir = DLG_DIR_UPSTREAM;
				}
			}
		}
		return dlg;
	}

	if(pre_match_parse(msg, &callid, &ftag, &ttag, 0) < 0)
		return NULL;
	vdir = DLG_DIR_NONE;
	dlg = get_dlg(&callid, &ftag, &ttag, &vdir);
	if(dlg == NULL) {
		LM_DBG("dlg with callid '%.*s' not found\n", msg->callid->body.len,
				msg->callid->body.s);
		return NULL;
	}
	if((dlg_ctxiuid_mode & DLG_CTXIUID_MODE_CANCEL) && IS_SIP_REQUEST(msg)
			&& (msg->first_line.u.request.method_value == METHOD_CANCEL)) {
		dlg_set_ctx_iuid(dlg);
	}
	if(dir)
		*dir = vdir;
	return dlg;
}

/*!
 *
 */
dlg_cell_t *dlg_get_msg_dialog(sip_msg_t *msg)
{
	return dlg_lookup_msg_dialog(msg, NULL);
}

/*!
 * \brief Function that is registered as RR callback for dialog tracking
 *
 * Function that is registered as RR callback for dialog tracking. It
 * sets the appropriate events after the SIP method and run the state
 * machine to update the dialog state. It updates then the saved
 * dialogs and also the statistics.
 * \param req SIP request
 * \param route_params record-route parameter
 * \param param unused
 */
void dlg_onroute(struct sip_msg *req, str *route_params, void *param)
{
	dlg_cell_t *dlg = NULL;
	dlg_iuid_t *iuid = NULL;
	str val, callid, ftag, ttag;
	int h_entry = 0, h_id = 0, new_state = 0, old_state = 0;
	int unref = 0, event = 0, timeout = 0, reset = 0;
	unsigned int dir = 0;
	int ret = 0;

	dlg = dlg_get_ctx_dialog();
	if(dlg != NULL) {
		dlg_release(dlg);
		return;
	}

	/* skip initial requests - they may end up here because of the
	 * preloaded route */
	if((!req->to && parse_headers(req, HDR_TO_F, 0) < 0) || !req->to) {
		LM_ERR("bad request or missing TO hdr :-/\n");
		return;
	}
	if(get_to(req)->tag_value.len == 0)
		return;

	dlg = 0;
	dir = DLG_DIR_NONE;

	if(seq_match_mode != SEQ_MATCH_NO_ID) {
		if(d_rrb.get_route_param(req, &rr_param, &val) != 0) {
			LM_DBG("Route param '%.*s' not found\n", rr_param.len, rr_param.s);
			if(seq_match_mode == SEQ_MATCH_STRICT_ID)
				return;
		} else {
			LM_DBG("route param is '%.*s' (len=%d)\n", val.len, val.s, val.len);

			if(parse_dlg_rr_param(val.s, val.s + val.len, &h_entry, &h_id) < 0)
				return;

			dlg = dlg_lookup(h_entry, h_id);
			if(dlg == 0) {
				LM_WARN("unable to find dialog for %.*s "
						"with route param '%.*s' [%u:%u] "
						"and call-id '%.*s'\n",
						req->first_line.u.request.method.len,
						req->first_line.u.request.method.s, val.len, val.s,
						h_entry, h_id, req->callid->body.len,
						req->callid->body.s);
				if(seq_match_mode == SEQ_MATCH_STRICT_ID)
					return;
			} else {
				if(pre_match_parse(req, &callid, &ftag, &ttag, 1) < 0) {
					// lookup_dlg has incremented the ref count by 1
					dlg_release(dlg);
					return;
				}
				if(match_dialog(dlg, &callid, &ftag, &ttag, &dir) == 0) {
					LM_WARN("tight matching failed for %.*s with "
							"callid='%.*s'/%d, "
							"ftag='%.*s'/%d, ttag='%.*s'/%d and direction=%d\n",
							req->first_line.u.request.method.len,
							req->first_line.u.request.method.s, callid.len,
							callid.s, callid.len, ftag.len, ftag.s, ftag.len,
							ttag.len, ttag.s, ttag.len, dir);
					LM_WARN("dialog identification elements are "
							"callid='%.*s'/%d, "
							"caller tag='%.*s'/%d, callee tag='%.*s'/%d\n",
							dlg->callid.len, dlg->callid.s, dlg->callid.len,
							dlg->tag[DLG_CALLER_LEG].len,
							dlg->tag[DLG_CALLER_LEG].s,
							dlg->tag[DLG_CALLER_LEG].len,
							dlg->tag[DLG_CALLEE_LEG].len,
							dlg->tag[DLG_CALLEE_LEG].s,
							dlg->tag[DLG_CALLEE_LEG].len);
					// lookup_dlg has incremented the ref count by 1
					dlg_release(dlg);

					// Reset variables in order to do a lookup based on SIP-Elements.
					dlg = 0;
					dir = DLG_DIR_NONE;

					if(seq_match_mode == SEQ_MATCH_STRICT_ID)
						return;
				}
			}
		}
	}

	if(dlg == 0) {
		if(pre_match_parse(req, &callid, &ftag, &ttag, 1) < 0)
			return;
		/* TODO - try to use the RR dir detection to speed up here the
		 * search -bogdan */
		dlg = get_dlg(&callid, &ftag, &ttag, &dir);
		if(dlg == 0) {
			LM_DBG("Callid '%.*s' not found\n", req->callid->body.len,
					req->callid->body.s);
			return;
		}
	}

	/* set current dialog - re-use ref increment from dlg_get() above */
	set_current_dialog(req, dlg);
	h_entry = dlg->h_entry;
	h_id = dlg->h_id;
	_dlg_ctx.iuid.h_entry = h_entry;
	_dlg_ctx.iuid.h_id = h_id;

	if(dlg->iflags & DLG_IFLAG_CSEQ_DIFF) {
		if(dlg_cseq_refresh(req, dlg, dir) < 0) {
			LM_ERR("failed to refresh cseq update\n");
		}
	}

	if(req->first_line.u.request.method_value != METHOD_ACK) {
		iuid = dlg_get_iuid_shm_clone(dlg);
		if(iuid != NULL) {
			/* register callback for the replies of this request */
			if(d_tmb.register_tmcb(req, 0, TMCB_RESPONSE_IN | TMCB_ON_FAILURE,
					   dlg_onreply, (void *)iuid, dlg_iuid_sfree)
					< 0) {
				LM_ERR("failed to register TMCB (3)\n");
				shm_free(iuid);
			}
			iuid = NULL;
		}
	}

	/* run state machine */
	switch(req->first_line.u.request.method_value) {
		case METHOD_PRACK:
			event = DLG_EVENT_REQPRACK;
			break;
		case METHOD_ACK:
			event = DLG_EVENT_REQACK;
			break;
		case METHOD_BYE:
			event = DLG_EVENT_REQBYE;
			break;
		default:
			event = DLG_EVENT_REQ;
	}

	next_state_dlg(dlg, event, &old_state, &new_state, &unref);

	CURR_DLG_ID = req->id;
	CURR_DLG_LIFETIME = (unsigned int)(time(0)) - dlg->start_ts;
	CURR_DLG_STATUS = new_state;

	if(dlg_run_event_route(dlg, req, old_state, new_state) < 0) {
		/* dialog is gone */
		return;
	}

	/* delay deletion of dialog until transaction has died off in order
	 * to absorb in-air messages */
	if(new_state == DLG_STATE_DELETED && old_state != DLG_STATE_DELETED) {
		/* set end time */
		dlg->end_ts = (unsigned int)(time(0));
		iuid = dlg_get_iuid_shm_clone(dlg);
		if(iuid != NULL) {
			if(d_tmb.register_tmcb(req, NULL, TMCB_DESTROY, unref_dlg_from_cb,
					   (void *)iuid, dlg_iuid_sfree)
					< 0) {
				LM_ERR("failed to register deletion delay function\n");
				shm_free(iuid);
			} else {
				dlg_ref(dlg, 1);
			}
		}
	}

	if(new_state == DLG_STATE_CONFIRMED && old_state != DLG_STATE_CONFIRMED)
		dlg_ka_add(dlg);

	/* run actions for the transition */
	if(event == DLG_EVENT_REQBYE && new_state == DLG_STATE_DELETED
			&& old_state != DLG_STATE_DELETED) {
		LM_DBG("BYE successfully processed\n");
		/* remove from timer */
		ret = remove_dialog_timer(&dlg->tl);
		if(ret < 0) {
			LM_CRIT("unable to unlink the timer on dlg %p [%u:%u] "
					"with clid '%.*s' and tags '%.*s' '%.*s'\n",
					dlg, dlg->h_entry, dlg->h_id, dlg->callid.len,
					dlg->callid.s, dlg->tag[DLG_CALLER_LEG].len,
					dlg->tag[DLG_CALLER_LEG].s, dlg->tag[DLG_CALLEE_LEG].len,
					dlg->tag[DLG_CALLEE_LEG].s);
		} else if(ret > 0) {
			LM_WARN("inconsistent dlg timer data on dlg %p [%u:%u] "
					"with clid '%.*s' and tags '%.*s' '%.*s'\n",
					dlg, dlg->h_entry, dlg->h_id, dlg->callid.len,
					dlg->callid.s, dlg->tag[DLG_CALLER_LEG].len,
					dlg->tag[DLG_CALLER_LEG].s, dlg->tag[DLG_CALLEE_LEG].len,
					dlg->tag[DLG_CALLEE_LEG].s);
		} else {
			/* one extra unref due to removal from timer list */
			unref++;
		}
		/* dialog terminated (BYE) */
		dlg_terminated(req, dlg, dir);

		dlg_unref(dlg, unref);

		_dlg_ctx.cpid = my_pid();
		_dlg_ctx.expect_t = 1;
		dlg_set_ctx_iuid(dlg);

		if_update_stat(dlg_enable_stats, active_dlgs, -1);
		goto done;
	}

	if((event == DLG_EVENT_REQ || event == DLG_EVENT_REQACK
			   || event == DLG_EVENT_REQPRACK)
			&& (new_state == DLG_STATE_CONFIRMED
					|| new_state == DLG_STATE_EARLY)) {

		timeout = get_dlg_timeout(req);
		if(timeout != default_timeout) {
			dlg->lifetime = timeout;
		}
		reset = !(
				(dlg->iflags & DLG_IFLAG_TIMER_NORESET) || dlg_timeout_noreset);

		if((new_state != DLG_STATE_EARLY)
				&& (old_state != DLG_STATE_CONFIRMED || reset)) {
			if(update_dlg_timer(&dlg->tl, dlg->lifetime) == -1) {
				LM_ERR("failed to update dialog lifetime\n");
			} else {
				dlg->dflags |= DLG_FLAG_CHANGED;
			}
		}
		if(event != DLG_EVENT_REQACK) {
			if(dlg_refresh_contacts(dlg, req, dir) != 0) {
				LM_ERR("contacts update failed\n");
			} else {
				dlg->dflags |= DLG_FLAG_CHANGED;
			}
			if(update_cseqs(dlg, req, dir) != 0) {
				LM_ERR("cseqs update failed\n");
			} else {
				dlg->dflags |= DLG_FLAG_CHANGED;
			}
		}
		if(dlg_db_mode == DB_MODE_REALTIME
				&& (dlg->dflags & DLG_FLAG_CHANGED)) {
			update_dialog_dbinfo(dlg);
		}

		if(old_state == DLG_STATE_CONFIRMED_NA) {
			LM_DBG("confirming ACK successfully processed\n");

			/* confirming ACK request */
			run_dlg_callbacks(DLGCB_CONFIRMED, dlg, req, NULL, dir, 0);
		} else {
			LM_DBG("sequential request successfully processed\n");

			/* within dialog request */
			run_dlg_callbacks(DLGCB_REQ_WITHIN, dlg, req, NULL, dir, 0);
			if(add_dlg_rr_param(req, dlg->h_entry, dlg->h_id) < 0) {
				LM_ERR("failed to add RR param\n");
				goto done;
			}

			if((event != DLG_EVENT_REQACK)
					&& (dlg->cbs.types) & DLGCB_RESPONSE_WITHIN) {
				iuid = dlg_get_iuid_shm_clone(dlg);
				if(iuid != NULL) {
					/* register callback for the replies of this request */
					if(d_tmb.register_tmcb(req, 0, TMCB_RESPONSE_FWDED,
							   (dir == DLG_DIR_UPSTREAM) ? dlg_seq_down_onreply
														 : dlg_seq_up_onreply,
							   (void *)iuid, dlg_iuid_sfree)
							< 0) {
						LM_ERR("failed to register TMCB (2)\n");
						shm_free(iuid);
					}
				}
			}
		}
	}

	if(new_state == DLG_STATE_CONFIRMED
			&& old_state == DLG_STATE_CONFIRMED_NA) {
		dlg->dflags |= DLG_FLAG_CHANGED;
		if(dlg_db_mode == DB_MODE_REALTIME)
			update_dialog_dbinfo(dlg);
	}

done:
	if(dlg_enable_dmq && (dlg->iflags & DLG_IFLAG_DMQ_SYNC)
			&& new_state > old_state) {
		dlg_dmq_replicate_action(DLG_DMQ_STATE, dlg, 0, 0);
	}

	dlg_release(dlg);
	return;
}


/*!
 * \brief Timer function that removes expired dialogs, run timeout route
 * \param tl dialog timer list
 */
void dlg_ontimeout(struct dlg_tl *tl)
{
	dlg_cell_t *dlg;
	int new_state, old_state, unref;
	sip_msg_t *fmsg;
	void *timeout_cb = 0;
	sr_kemi_eng_t *keng = NULL;
	str evname;

	/* get the dialog tl payload */
	dlg = ((struct dlg_cell *)((char *)(tl)
							   - (unsigned long)(&((struct dlg_cell *)0)->tl)));

	if(dlg_filter_mode & DLG_FILTER_LOCALONLY) {
		if(dlg->bind_addr[0] == NULL) {
			LM_DBG("skipping dialog without bind address\n");
			return;
		}

		if(lookup_local_socket(&(dlg->bind_addr[0]->sock_str)) == NULL) {
			LM_DBG("skipping non local dialog\n");
			return;
		}
	}

	/* mark dialog as expired */
	dlg->dflags |= DLG_FLAG_EXPIRED;

	if(dlg->state == DLG_STATE_CONFIRMED_NA
			|| dlg->state == DLG_STATE_CONFIRMED) {
		if((dlg->toroute > 0 && dlg->toroute < main_rt.entries
				   && main_rt.rlist[dlg->toroute] != NULL)
				|| (dlg->toroute_name.len > 0 && dlg_event_callback.s != NULL
						&& dlg_event_callback.len > 0)) {
			fmsg = faked_msg_next();
			if(exec_pre_script_cb(fmsg, REQUEST_CB_TYPE) > 0) {
				dlg_ref(dlg, 1);
				dlg_set_ctx_iuid(dlg);
				LM_DBG("executing route %d on timeout\n", dlg->toroute);
				set_route_type(REQUEST_ROUTE);
				if(dlg->toroute > 0) {
					run_top_route(main_rt.rlist[dlg->toroute], fmsg, 0);
				} else {
					keng = sr_kemi_eng_get();
					if(keng != NULL) {
						evname.s = "dialog:timeout";
						evname.len = sizeof("dialog:timeout") - 1;
						if(sr_kemi_route(keng, fmsg, EVENT_ROUTE,
								   &dlg_event_callback, &evname)
								< 0) {
							LM_ERR("error running event route kemi callback\n");
						}
					}
				}
				dlg_reset_ctx_iuid();
				exec_post_script_cb(fmsg, REQUEST_CB_TYPE);
				dlg_unref(dlg, 1);
			}
		}

		if(dlg->iflags & DLG_IFLAG_TIMEOUTBYE) {
			/* set the dialog context so that it's available in
			 * tm:local-request event route */
			dlg_set_ctx_iuid(dlg);
			if(dlg_bye_all(dlg, NULL) < 0)
				dlg_unref(dlg, 1);
			dlg_reset_ctx_iuid();

			dlg_unref(dlg, 1);
			if_update_stat(dlg_enable_stats, expired_dlgs, 1);
			return;
		}
	}

	next_state_dlg(dlg, DLG_EVENT_REQBYE, &old_state, &new_state, &unref);
	/* used for computing duration for timed out acknowledged dialog */
	if(DLG_STATE_CONFIRMED == old_state) {
		timeout_cb = (void *)CONFIRMED_DIALOG_STATE;
	}

	if(dlg_run_event_route(dlg, NULL, old_state, new_state) < 0) {
		/* dialog is gone */
		return;
	}

	if(new_state == DLG_STATE_DELETED && old_state != DLG_STATE_DELETED) {
		LM_WARN("dlg timeout - callid: '%.*s' tags: '%.*s' '%.*s' ostate: %d\n",
				dlg->callid.len, dlg->callid.s, dlg->tag[DLG_CALLER_LEG].len,
				dlg->tag[DLG_CALLER_LEG].s, dlg->tag[DLG_CALLEE_LEG].len,
				dlg->tag[DLG_CALLEE_LEG].s, old_state);

		/* set end time */
		dlg->end_ts = (unsigned int)(time(0));

		/* dialog timeout */
		run_dlg_callbacks(
				DLGCB_EXPIRED, dlg, NULL, NULL, DLG_DIR_NONE, timeout_cb);

		dlg_unref(dlg, unref + 1);

		if_update_stat(dlg_enable_stats, expired_dlgs, 1);
		if_update_stat(dlg_enable_stats, active_dlgs, -1);
	} else {
		dlg_unref(dlg, 1);
	}

	if(dlg_enable_dmq && (dlg->iflags & DLG_IFLAG_DMQ_SYNC)
			&& new_state > old_state) {
		dlg_dmq_replicate_action(DLG_DMQ_STATE, dlg, 0, 0);
	}

	return;
}


/*!
 * \brief Function that returns the dialog lifetime as pseudo-variable
 * \param msg SIP message
 * \param param pseudo-variable parameter
 * \param res pseudo-variable result
 * \return 0 on success, -1 on failure
 */
int pv_get_dlg_lifetime(struct sip_msg *msg, pv_param_t *param, pv_value_t *res)
{
	int l = 0;
	char *ch = NULL;

	if(msg == NULL || res == NULL)
		return -1;

	if(CURR_DLG_ID != msg->id)
		return pv_get_null(msg, param, res);

	res->ri = CURR_DLG_LIFETIME;
	ch = int2str((unsigned long)res->ri, &l);

	res->rs.s = ch;
	res->rs.len = l;

	res->flags = PV_VAL_STR | PV_VAL_INT | PV_TYPE_INT;

	return 0;
}


/*!
 * \brief Function that returns the dialog state as pseudo-variable
 * \param msg SIP message
 * \param param pseudo-variable parameter
 * \param res pseudo-variable result
 * \return 0 on success, -1 on failure
 */
int pv_get_dlg_status(struct sip_msg *msg, pv_param_t *param, pv_value_t *res)
{
	int l = 0;
	char *ch = NULL;

	if(msg == NULL || res == NULL)
		return -1;

	if(CURR_DLG_ID != msg->id)
		return pv_get_null(msg, param, res);

	res->ri = CURR_DLG_STATUS;
	ch = int2str((unsigned long)res->ri, &l);

	res->rs.s = ch;
	res->rs.len = l;

	res->flags = PV_VAL_STR | PV_VAL_INT | PV_TYPE_INT;

	return 0;
}

/*!
 * \brief Execute event routes based on new state
 * - returns: -1 if dialog doesn't exist after event route execution
 *             0 if all ok
 */
int dlg_run_event_route(dlg_cell_t *dlg, sip_msg_t *msg, int ostate, int nstate)
{
	sip_msg_t *fmsg;
	int rt;
	int bkroute;
	sr_kemi_eng_t *keng = NULL;
	str evname = str_init("unknown");
	int h_entry = 0;
	int h_id = 0;
	dlg_cell_t *dlg0 = NULL;

	if(dlg == NULL)
		return -1;
	if(ostate == nstate)
		return 0;

	rt = -1;
	if(dlg_event_callback.s == NULL || dlg_event_callback.len <= 0) {
		if(nstate == DLG_STATE_CONFIRMED_NA) {
			rt = dlg_event_rt[DLG_EVENTRT_START];
		} else if(nstate == DLG_STATE_DELETED) {
			if(ostate == DLG_STATE_CONFIRMED
					|| ostate == DLG_STATE_CONFIRMED_NA) {
				rt = dlg_event_rt[DLG_EVENTRT_END];
			} else if(ostate == DLG_STATE_UNCONFIRMED
					  || ostate == DLG_STATE_EARLY) {
				rt = dlg_event_rt[DLG_EVENTRT_FAILED];
			}
		}
		if(rt == -1 || event_rt.rlist[rt] == NULL)
			return 0;
	} else {
		if(nstate == DLG_STATE_CONFIRMED_NA) {
			evname.s = "dialog:start";
			evname.len = sizeof("dialog:start") - 1;
		} else if(nstate == DLG_STATE_DELETED) {
			if(ostate == DLG_STATE_CONFIRMED
					|| ostate == DLG_STATE_CONFIRMED_NA) {
				evname.s = "dialog:end";
				evname.len = sizeof("dialog:end") - 1;
			} else if(ostate == DLG_STATE_UNCONFIRMED
					  || ostate == DLG_STATE_EARLY) {
				evname.s = "dialog:failed";
				evname.len = sizeof("dialog:failed") - 1;
			}
		}
		keng = sr_kemi_eng_get();
		if(keng == NULL) {
			LM_DBG("event callback (%s) set, but no cfg engine\n",
					dlg_event_callback.s);
			return 0;
		}
	}

	if(rt >= 0 || dlg_event_callback.len > 0) {
		if(msg == NULL)
			fmsg = faked_msg_next();
		else
			fmsg = msg;

		if(exec_pre_script_cb(fmsg, LOCAL_CB_TYPE) <= 0)
			return 0;

		dlg_ref(dlg, 1);
		h_entry = dlg->h_entry;
		h_id = dlg->h_id;
		dlg_set_ctx_iuid(dlg);
		LM_DBG("executing event_route %d on state %d\n", rt, nstate);
		bkroute = get_route_type();
		set_route_type(LOCAL_ROUTE);
		if(rt >= 0) {
			run_top_route(event_rt.rlist[rt], fmsg, 0);
		} else {
			if(keng != NULL) {
				if(sr_kemi_route(keng, fmsg, EVENT_ROUTE, &dlg_event_callback,
						   &evname)
						< 0) {
					LM_ERR("error running event route kemi callback (%d %d)\n",
							ostate, nstate);
				}
			}
		}
		dlg_reset_ctx_iuid();
		exec_post_script_cb(fmsg, LOCAL_CB_TYPE);
		set_route_type(bkroute);
		/* re-lookup the dialog, execution of the route could take long time */
		dlg0 = dlg_lookup(h_entry, h_id);
		if(dlg0 == 0) {
			LM_ALERT("after event route - dialog not found [%u:%u] (%d/%d) "
					 "(%p) (%.*s)\n",
					h_entry, h_id, ostate, nstate, dlg, evname.len, evname.s);
			if(nstate == DLG_STATE_DELETED) {
				if(ostate == DLG_STATE_UNCONFIRMED) {
					if_update_stat(dlg_enable_stats, failed_dlgs, 1);
				} else if(ostate == DLG_STATE_EARLY) {
					if_update_stat(dlg_enable_stats, early_dlgs, -1);
					if_update_stat(dlg_enable_stats, failed_dlgs, 1);
				} else if(ostate != DLG_STATE_DELETED) {
					if_update_stat(dlg_enable_stats, active_dlgs, -1);
				}
			}
			return -1;
		} else {
			dlg_release(dlg0);
			dlg_unref(dlg, 1);
		}
	}
	return 0;
}

/*!
 *
 */
int dlg_set_state(sip_msg_t *msg, int istate)
{
	str sc = STR_NULL;
	str sf = STR_NULL;
	str st = STR_NULL;
	dlg_cell_t *dlg = NULL;
	unsigned int dir = 0;
	int ostate = 0;

	if(msg->callid == NULL
			&& ((parse_headers(msg, HDR_CALLID_F, 0) == -1)
					|| (msg->callid == NULL))) {
		LM_ERR("cannot parse Call-Id header\n");
		return -1;
	}
	if(parse_from_header(msg) < 0) {
		LM_ERR("cannot parse From header\n");
		return -1;
	}
	if(parse_to_header(msg) < 0) {
		LM_ERR("cannot parse To header\n");
		return -1;
	}
	if(msg->first_line.type != SIP_REQUEST
			&& msg->first_line.type != SIP_REPLY) {
		LM_ERR("unknown message type\n");
		return -1;
	}
	sc = msg->callid->body;
	sf = get_from(msg)->tag_value;
	st = get_to(msg)->tag_value;

	dlg = get_dlg(&sc, &sf, &st, &dir);
	if(dlg == NULL) {
		LM_DBG("dialog not found\n");
		return -1;
	}
	ostate = dlg->state;
	dlg->state = istate;
	/* updates for terminated dialogs */
	if(ostate == DLG_STATE_CONFIRMED && istate == DLG_STATE_DELETED) {
		/* updating timestamps, flags, dialog stats */
		dlg->init_ts = (unsigned int)(time(0));
		dlg->end_ts = (unsigned int)(time(0));
	}
	dlg->dflags |= DLG_FLAG_CHANGED;
	dlg_release(dlg);

	return 0;
}

/*!
 *
 */
int dlg_update_state(sip_msg_t *msg)
{
	str sc = STR_NULL;
	str sf = STR_NULL;
	str st = STR_NULL;
	dlg_cell_t *dlg = NULL;
	unsigned int dir = 0;
	int old_state = 0;
	int new_state = 0;
	int event = 0;
	int unref = 0;

	if(msg->callid == NULL
			&& ((parse_headers(msg, HDR_CALLID_F, 0) == -1)
					|| (msg->callid == NULL))) {
		LM_ERR("cannot parse Call-Id header\n");
		return -1;
	}
	if(parse_from_header(msg) < 0) {
		LM_ERR("cannot parse From header\n");
		return -1;
	}
	if(parse_to_header(msg) < 0) {
		LM_ERR("cannot parse To header\n");
		return -1;
	}
	if(msg->first_line.type != SIP_REQUEST
			&& msg->first_line.type != SIP_REPLY) {
		LM_ERR("unknown message type\n");
		return -1;
	}
	sc = msg->callid->body;
	sf = get_from(msg)->tag_value;
	st = get_to(msg)->tag_value;

	if(msg->first_line.type == SIP_REQUEST) {
		switch(msg->first_line.u.request.method_value) {
			case METHOD_PRACK:
				event = DLG_EVENT_REQPRACK;
				break;
			case METHOD_ACK:
				event = DLG_EVENT_REQACK;
				break;
			case METHOD_BYE:
				event = DLG_EVENT_REQBYE;
				break;
			default:
				event = DLG_EVENT_REQ;
		}
	} else {
		if(msg->first_line.u.reply.statuscode < 200) {
			event = DLG_EVENT_RPL1xx;
		} else if(msg->first_line.u.reply.statuscode < 300) {
			event = DLG_EVENT_RPL2xx;
		} else {
			event = DLG_EVENT_RPL3xx;
		}
	}

	dlg = get_dlg(&sc, &sf, &st, &dir);
	if(dlg == NULL) {
		LM_DBG("dialog not found\n");
		return -1;
	}
	next_state_dlg(dlg, event, &old_state, &new_state, &unref);
	dlg->dflags |= DLG_FLAG_CHANGED;
	if(unref > 0) {
		dlg_unref(dlg, unref);
	}
	dlg_release(dlg);

	return 0;
}

/*!
 *
 */
int dlg_manage(sip_msg_t *msg)
{
	str tag;
	int backup_mode;
	dlg_cell_t *dlg = NULL;
	tm_cell_t *t = NULL;

	if((msg->to == NULL && parse_headers(msg, HDR_TO_F, 0) < 0)
			|| msg->to == NULL) {
		LM_ERR("bad TO header\n");
		return -1;
	}
	tag = get_to(msg)->tag_value;
	if(tag.s != 0 && tag.len != 0) {
		backup_mode = seq_match_mode;
		seq_match_mode = SEQ_MATCH_NO_ID;
		dlg_onroute(msg, NULL, NULL);
		seq_match_mode = backup_mode;
	} else {
		t = d_tmb.t_gett();
		if(t == T_UNDEFINED)
			t = NULL;
		if(dlg_new_dialog(msg, t, initial_cbs_inscript) != 0)
			return -1;
		dlg = dlg_get_ctx_dialog();
		if(dlg == NULL)
			return -1;
		if(t != NULL) {
			dlg_set_tm_callbacks(t, msg, dlg, spiral_detected);
			_dlg_ctx.t = 1;
			LM_DBG("dialog created on existing transaction\n");
		} else {
			LM_DBG("dialog created before transaction\n");
		}
		dlg_release(dlg);
	}
	return 1;
}
