nua_dialog.c

Sofia SIP is an open-source SIP User-Agent library, compliant with the IETF RFC3261 specification.

/*
 * This file is part of the Sofia-SIP package
 *
 * Copyright (C) 2006 Nokia Corporation.
 *
 * Contact: Pekka Pessi <[e-mail]>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

/**@CFILE nua_dialog.c
 * @brief Dialog and dialog usage handling
 *
 * @author Pekka Pessi <[e-mail]>
 *
 * @date Created: Wed Mar  8 11:48:49 EET 2006 ppessi
 */

#include "config.h"

#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>

#include <assert.h>

#include <sofia-sip/string0.h>
#include <sofia-sip/su_uniqueid.h>

#include <sofia-sip/sip_protos.h>
#include <sofia-sip/sip_status.h>

#define NUA_OWNER_T su_home_t

#include "nua_dialog.h"

#define SU_LOG (nua_log)
#include <sofia-sip/su_debug.h>

#ifndef NONE
#define NONE ((void *)-1)
#endif

/* ======================================================================== */
/* Dialog handling */

static void nua_dialog_usage_remove_at(nua_owner_t*, nua_dialog_state_t*, 
				       nua_dialog_usage_t**,
				       nua_client_request_t *cr,
				       nua_server_request_t *sr);
static void nua_dialog_log_usage(nua_owner_t *, nua_dialog_state_t *);

/**@internal
 * UAS tag and route.
 *
 * Update dialog tags and route on the UAS side.
 *
 * @param own  dialog owner
 * @param ds   dialog state
 * @param sip  SIP message containing response used to update dialog
 * @param rtag if true, set remote tag within the leg
 */
void nua_dialog_uas_route(nua_owner_t *own, 
			  nua_dialog_state_t *ds,
			  sip_t const *sip, 
			  int rtag)
{
  int established = nua_dialog_is_established(ds);

  if (!established && sip->sip_from->a_tag)
    ds->ds_remote_tag = su_strdup(own, sip->sip_from->a_tag);

  if (ds->ds_leg == NULL)
    return;

  nta_leg_server_route(ds->ds_leg, sip->sip_record_route, sip->sip_contact);
  ds->ds_route = ds->ds_route || sip->sip_record_route || sip->sip_contact;

  if (rtag && !established && sip->sip_from->a_tag)
    nta_leg_rtag(ds->ds_leg, sip->sip_from->a_tag);
}

/**@internal
 * UAC tag and route.
 *
 * Update dialog tags and route on the UAC side.
 *
 * @param own  dialog owner
 * @param ds   dialog state
 * @param sip  SIP message containing response used to update dialog
 * @param rtag if true, set remote tag within the leg
 */
void nua_dialog_uac_route(nua_owner_t *own, 
			  nua_dialog_state_t *ds,
			  sip_t const *sip,
			  int rtag)
{
  int established = nua_dialog_is_established(ds);

  if (!established && sip->sip_to->a_tag)
    ds->ds_remote_tag = su_strdup(own, sip->sip_to->a_tag);

  if (ds->ds_leg == NULL)
    return;

  nta_leg_client_route(ds->ds_leg, sip->sip_record_route, sip->sip_contact);
  ds->ds_route = ds->ds_route || sip->sip_record_route || sip->sip_contact;

  if (rtag && !established && sip->sip_to->a_tag)
    nta_leg_rtag(ds->ds_leg, sip->sip_to->a_tag);
}

/**@internal Store information from remote endpoint. */
void nua_dialog_store_peer_info(nua_owner_t *own, 
				nua_dialog_state_t *ds,
				sip_t const *sip)
{
  nua_dialog_peer_info_t *nr = ds->ds_remote_ua;
  nua_dialog_usage_t *du;
  nua_dialog_peer_info_t old[1];

  *old = *nr;

  if (sip && sip->sip_status &&
      sip->sip_status->st_status >= 300 &&
      sip->sip_status->st_status <= 399)
    sip = NULL;			/* Redirected */

  if (sip == NULL) {
    nr->nr_allow = NULL, su_free(own, old->nr_allow);
    nr->nr_accept = NULL, su_free(own, old->nr_accept);
    nr->nr_require = NULL, su_free(own, old->nr_require);
    nr->nr_supported = NULL, su_free(own, old->nr_supported);
    nr->nr_user_agent = NULL, su_free(own, old->nr_user_agent);
    return;
  }

  if (sip->sip_allow) {
    nr->nr_allow = sip_allow_dup(own, sip->sip_allow);
    su_free(own, old->nr_allow);
  }

  if (sip->sip_accept) {
    nr->nr_accept = sip_accept_dup(own, sip->sip_accept);
    su_free(own, old->nr_accept);
  }

  if (sip->sip_require) {
    nr->nr_require = sip_require_dup(own, sip->sip_require);
    su_free(own, old->nr_require);
  }

  if (sip->sip_supported) {
    nr->nr_supported = sip_supported_dup(own, sip->sip_supported);
    su_free(own, old->nr_supported);
  }

  if (sip->sip_user_agent) {
    nr->nr_user_agent = sip_user_agent_dup(own, sip->sip_user_agent);
    su_free(own, old->nr_user_agent);
  }
  else if (sip->sip_server) {
    nr->nr_user_agent = sip_user_agent_dup(own, sip->sip_server);
    su_free(own, old->nr_user_agent);
  }

  for (du = ds->ds_usage; du; du = du->du_next) {
    if (du->du_class->usage_peer_info)
      du->du_class->usage_peer_info(du, ds, sip);
  }
}

/** Remove dialog information. */
int nua_dialog_zap(nua_owner_t *own,
		   nua_dialog_state_t *ds)
{
  /* zap peer info */
  nua_dialog_store_peer_info(own, ds, NULL); 
  /* Local Contact */
  msg_header_free(own, (msg_header_t *)ds->ds_ltarget), ds->ds_ltarget = NULL;
  /* Leg */
  nta_leg_destroy(ds->ds_leg), ds->ds_leg = NULL;
  /* Remote tag */
  su_free(own, (void *)ds->ds_remote_tag), ds->ds_remote_tag = NULL;
  /* Ready to set route/remote target */
  ds->ds_route = 0;

  return 0;
}

/** Remove dialog (if there is no other usages). */
int nua_dialog_remove(nua_owner_t *own,
		      nua_dialog_state_t *ds,
		      nua_dialog_usage_t *usage)
{
  if (ds->ds_usage == usage && (usage == NULL || usage->du_next == NULL)) {
    return nua_dialog_zap(own, ds);
  }
  return 0;
}

/** @internal Get dialog usage slot. */
nua_dialog_usage_t **
nua_dialog_usage_at(nua_dialog_state_t const *ds, 
		    nua_usage_class const *kind,
		    sip_event_t const *event)
{
  static nua_dialog_usage_t *none = NULL;

  if (ds) {
    nua_dialog_usage_t *du, * const * prev;
    sip_event_t const *o;

    for (prev = &ds->ds_usage; (du = *prev); prev = &du->du_next) {
      if (du->du_class != kind)
	continue;

      if (event == NONE)
	return (nua_dialog_usage_t **)prev;

      o = du->du_event;

      if (!event && !o)
	return (nua_dialog_usage_t **)prev;

      if (event != o) {
	if (event == NULL || o == NULL)
	  continue;
	if (strcmp(event->o_type, o->o_type))
	  continue;
	if (str0casecmp(event->o_id, o->o_id)) {
	  if (event->o_id || strcmp(event->o_type, "refer"))
	    continue;
	}
      }

      return (nua_dialog_usage_t **)prev;
    }
  }

  return &none;
}

/** @internal Get a dialog usage */
nua_dialog_usage_t *nua_dialog_usage_get(nua_dialog_state_t const *ds, 
					 nua_usage_class const *kind,
					 sip_event_t const *event)
{
  return *nua_dialog_usage_at(ds, kind, event);
}

/** @internal Get dialog usage name */
char const *nua_dialog_usage_name(nua_dialog_usage_t const *du)
{
  if (du == NULL)
    return "<NULL>";
  return du->du_class->usage_name(du);
} 

/** @internal Add dialog usage */
nua_dialog_usage_t *nua_dialog_usage_add(nua_owner_t *own, 
					 struct nua_dialog_state *ds, 
					 nua_usage_class const *uclass,
					 sip_event_t const *event)
{
  if (ds) {
    sip_event_t *o;
    nua_dialog_usage_t *du, **prev_du;

    prev_du = nua_dialog_usage_at(ds, uclass, event);
    du = *prev_du;
    if (du) {		/* Already exists */
      SU_DEBUG_5(("nua(%p): adding already existing %s usage%s%s\n",
		  (void *)own, nua_dialog_usage_name(du), 
		  event ? "  with event " : "", event ? event->o_type : ""));
      
      if (prev_du != &ds->ds_usage) {
	/* Move as a first usage in the list */
	*prev_du = du->du_next;
	du->du_next = ds->ds_usage;
	ds->ds_usage = du;
      }
      return du;
    }

    o = event ? sip_event_dup(own, event) : NULL;

    if (o != NULL || event == NULL)
      du = su_zalloc(own, sizeof *du + uclass->usage_size);

    if (du) {
      su_home_ref(own);
      du->du_dialog = ds; 
      du->du_class = uclass;
      du->du_event = o;

      if (uclass->usage_add(own, ds, du) < 0) {
	su_free(own, o);
	su_free(own, du);
	return NULL;
      }
	
      SU_DEBUG_5(("nua(%p): adding %s usage%s%s\n",
		  (void *)own, nua_dialog_usage_name(du), 
		  o ? " with event " : "", o ? o->o_type :""));

      du->du_next = ds->ds_usage, ds->ds_usage = du;

      return du;
    }

    su_free(own, o);