outbound.c 35.5 KB
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/*
 * This file is part of the Sofia-SIP package
 *
 * Copyright (C) 2005 Nokia Corporation.
 *
 * Contact: Pekka Pessi <pekka.pessi@nokia.com>
 *
 * 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 outbound.c
 * @brief Implementation of SIP NAT traversal and outbound
 *
 * @author Pekka Pessi <Pekka.Pessi@nokia.com>
 * @author Kai Vehmanen <Kai.Vehmanen@nokia.com>
 * @author Martti Mela <Martti Mela@nokia.com>
 *
 * @date Created: Wed May 10 12:11:54 EEST 2006 ppessi
 */

#include "config.h"

#define NTA_OUTGOING_MAGIC_T struct outbound

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#include "outbound.h"
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#include <sofia-sip/hostdomain.h>
#include <sofia-sip/sip.h>
#include <sofia-sip/sip_protos.h>
#include <sofia-sip/sip_util.h>
#include <sofia-sip/sip_status.h>
#include <sofia-sip/su_tagarg.h>
#include <sofia-sip/tport.h>
#include <sofia-sip/nta_tport.h>

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#include <sofia-sip/su_md5.h>
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#include <sofia-sip/su_uniqueid.h>
#include <sofia-sip/token64.h>

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

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#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>

struct outbound {
  su_home_t ob_home[1];
  outbound_owner_vtable
  const *ob_oo;			/**< Callbacks */
  outbound_owner_t *ob_owner;	/**< Backpointer */

  su_root_t *ob_root;		/**< Root for timers and stuff */
  nta_agent_t *ob_nta;		/**< SIP transactions */

  char ob_cookie[32];		/**< Our magic cookie */

  struct outbound_prefs {
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    unsigned interval;	/**< Default keepalive interval for datagram */
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    unsigned stream_interval;	/**< Default keepalive interval for streams */
    unsigned gruuize:1;		/**< Establish a GRUU */
    unsigned outbound:1;	/**< Try to use outbound */
    unsigned natify:1;		/**< Try to detect NAT */
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    signed okeepalive:2;	/**< Connection keepalive with OPTIONS */
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    unsigned validate:1;	/**< Validate registration with OPTIONS */
    /* How to detect NAT binding or connect to outbound: */
    unsigned use_connect:1;	/**< Use HTTP connect */
    unsigned use_rport:1;	/**< Use received/rport */
    unsigned use_socks:1;	/**< Detect and use SOCKS V5 */
    unsigned use_upnp:1;	/**< Detect and use UPnP */
    unsigned use_stun:1;	/**< Detect and try to use STUN */
    unsigned :0;
  } ob_prefs;

  struct outbound_info {
    /* See enum outbound_feature: */
    /* 0 do not support, 1 - perhaps supports, 2 - supports, 3 - requires */
    unsigned gruu:2, outbound:2, pref:2;
  } ob_info;

  /** Source of Contact header */
  unsigned ob_by_stack:1;
  /** Self-generated contacts */
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  unsigned ob_contacts:1;
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  /* The registration state machine. */
  /** Initial REGISTER containing ob_rcontact has been sent */
  unsigned ob_registering:1;
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  /** 2XX response to REGISTER containing ob_rcontact has been received */
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  unsigned ob_registered:1;
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  /** The registration has been validated:
   *  We have successfully sent OPTIONS to ourselves.
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   */
  unsigned ob_validated:1;
  /** The registration has been validated once.
   *   We have successfully sent OPTIONS to ourselves, so do not give
   *   up if OPTIONS probe fails.
   */
  unsigned ob_once_validated:1;
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  unsigned ob_validate_timed_out:1;
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  unsigned ob_proxy_override:1;	/**< Override stack default proxy */
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  unsigned :0;

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  url_string_t *ob_proxy;	/**< Outbound-specific proxy */
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  char const *ob_instance;	/**< Our instance ID */
  int32_t ob_reg_id;		/**< Flow-id */
  sip_contact_t *ob_rcontact;	/**< Our contact */
  sip_contact_t *ob_dcontact;	/**< Contact for dialogs */
  sip_contact_t *ob_previous;	/**< Stale contact */
  sip_contact_t *ob_gruu;	/**< Contact added to requests */
  sip_via_t *ob_via;		/**< Via header used to generate contacts */

  sip_contact_t *ob_obp;	/**< Contacts from outbound proxy */

  char *ob_nat_detected;	/**< Our public address */
  char *ob_nat_port;		/**< Our public port number */

  void *ob_stun;		/**< Stun context */
  void *ob_upnp;		/**< UPnP context  */

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  /** Keepalive information */
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  struct {
    char *sipstun;		/**< Stun server usable for keep-alives */
    unsigned interval;		/**< Interval. */
    su_timer_t *timer;		/**< Keep-alive timer */
    msg_t *msg;			/**< Keep-alive OPTIONS message */
    nta_outgoing_t *orq;	/**< Keep-alive OPTIONS transaction */
    auth_client_t *auc[1];	/**< Authenticator for OPTIONS */
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    /** Progress of registration validation */
    unsigned validating:1, validated:1,:0;
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  } ob_keepalive;
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};

static
int outbound_nat_detect(outbound_t *ob,
       			 sip_t const *request,
       			 sip_t const *response);

/** Return values for outbound_nat_detect(). */
enum {
  ob_nat_error = -1,		/* or anything below zero */
  ob_no_nat = 0,
  ob_nat_detected = 1,
  ob_nat_changed = 2
};

/* ---------------------------------------------------------------------- */

#define SIP_METHOD_UNKNOWN sip_method_unknown, NULL

/** Content-Type sent in OPTIONS probing connectivity */
char const * const outbound_content_type = "application/vnd.nokia-register-usage";

static
int outbound_check_for_nat(outbound_t *ob,
			   sip_t const *request,
			   sip_t const *response);

enum outbound_feature {
  outbound_feature_unsupported = 0,
  outbound_feature_unsure = 1,
  outbound_feature_supported = 2,
  outbound_feature_required = 3
};

static enum outbound_feature feature_level(sip_t const *sip,
					   char const *tag, int level);

static int outbound_contacts_from_via(outbound_t *ob,
				      sip_via_t const *via);

/* ---------------------------------------------------------------------- */

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/** Create a new outbound object */
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outbound_t *
outbound_new(outbound_owner_t *owner,
	     outbound_owner_vtable const *owner_methods,
	     su_root_t *root,
	     nta_agent_t *agent,
	     char const *instance)
{
  outbound_t *ob;

  if (!owner || !owner_methods || !root || !agent)
    return NULL;

  ob = su_home_clone((su_home_t *)owner, sizeof *ob);
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  if (ob) {
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    su_md5_t md5[1];
    uint8_t digest[SU_MD5_DIGEST_SIZE];
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    su_guid_t guid[1];

    ob->ob_owner = owner;
    ob->ob_oo = owner_methods;
    ob->ob_root = root;
    ob->ob_nta = agent;

    if (instance)
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      ob->ob_instance =
	su_sprintf(ob->ob_home, "+sip.instance=\"<%s>\"", instance);
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    ob->ob_reg_id = 0;

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    outbound_peer_info(ob, NULL);

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    /* Generate a random cookie (used as Call-ID) for us */
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    su_md5_init(md5);
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    su_guid_generate(guid);
    if (instance)
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      su_md5_update(md5, (void *)instance, strlen(instance));
    su_md5_update(md5, (void *)guid, sizeof guid);
    su_md5_digest(md5, digest);
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    token64_e(ob->ob_cookie, sizeof ob->ob_cookie, digest, sizeof digest);
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    if (instance && !ob->ob_instance)
      su_home_unref(ob->ob_home), ob = NULL;
  }

  return ob;
}

void outbound_unref(outbound_t *ob)
{
  if (ob->ob_keepalive.timer)
    su_timer_destroy(ob->ob_keepalive.timer), ob->ob_keepalive.timer = NULL;

  if (ob->ob_keepalive.orq)
    nta_outgoing_destroy(ob->ob_keepalive.orq), ob->ob_keepalive.orq = NULL;

  if (ob->ob_keepalive.msg)
    msg_destroy(ob->ob_keepalive.msg), ob->ob_keepalive.msg = NULL;

  su_home_unref(ob->ob_home);
}

#include <sofia-sip/bnf.h>

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/** Set various outbound and nat-traversal related options. */
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int outbound_set_options(outbound_t *ob,
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			 char const *_options,
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			 unsigned interval,
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			 unsigned stream_interval)
{
  struct outbound_prefs prefs[1] = {{ 0 }};
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  char *s, *options = su_strdup(NULL, _options);
  int invalid;
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  prefs->interval = interval;
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  prefs->stream_interval = stream_interval;
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#define MATCH(v) (len == sizeof(#v) - 1 && su_casenmatch(#v, s, len))
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  if (options) {
    for (s = options; s[0]; s++) if (s[0] == '-') s[0] = '_';
  }

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  prefs->gruuize = 1;
  prefs->outbound = 0;
  prefs->natify = 1;
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  prefs->okeepalive = -1;
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  prefs->validate = 1;
  prefs->use_rport = 1;

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  for (s = options; s && s[0]; ) {
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    size_t len = span_token(s);
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    int value = 1;

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    if (len > 3 && su_casenmatch(s, "no_", 3))
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      value = 0, s += 3, len -= 3;
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    else if (len > 4 && su_casenmatch(s, "not_", 4))
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      value = 0, s += 4, len -= 4;
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    if (len == 0)
      break;
    else if (MATCH(gruuize)) prefs->gruuize = value;
    else if (MATCH(outbound)) prefs->outbound = value;
    else if (MATCH(natify)) prefs->natify = value;
    else if (MATCH(validate)) prefs->validate = value;
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    else if (MATCH(options_keepalive)) prefs->okeepalive = value;
    else if (MATCH(use_connect)) prefs->use_connect = value;
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    else if (MATCH(use_rport)) prefs->use_rport = value;
    else if (MATCH(use_socks)) prefs->use_socks = value;
    else if (MATCH(use_upnp)) prefs->use_upnp = value;
    else if (MATCH(use_stun)) prefs->use_stun = value;
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    else
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      SU_DEBUG_1(("outbound(%p): unknown option \"%.*s\"\n",
		  (void *)ob->ob_owner, (int)len, s));
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    s += len;
    len = strspn(s, " \t\n\r,;");
    if (len == 0)
      break;
    s += len;
  }

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  invalid = s && s[0];
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  if (invalid)
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    SU_DEBUG_1(("outbound(%p): invalid options \"%s\"\n",
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		(void *)ob->ob_owner, options));
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  su_free(NULL, options);
  if (invalid)
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    return -1;

  if (prefs->natify &&
      !(prefs->outbound ||
	prefs->use_connect ||
	prefs->use_rport ||
	prefs->use_socks ||
	prefs->use_upnp ||
	prefs->use_stun)) {
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    SU_DEBUG_1(("outbound(%p): no nat traversal method given\n",
		(void *)ob->ob_owner));
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  }

  ob->ob_prefs = *prefs;
  ob->ob_reg_id = prefs->outbound ? 1 : 0;

  return 0;
}

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/** Override stack default proxy for outbound */
int outbound_set_proxy(outbound_t *ob,
		       url_string_t *proxy)
{
  url_string_t *new_proxy = NULL, *old_proxy = ob->ob_proxy;

  if (proxy)
    new_proxy = (url_string_t *)url_as_string(ob->ob_home, proxy->us_url);

  if (proxy == NULL || new_proxy != NULL) {
    ob->ob_proxy_override = 1;
    ob->ob_proxy = new_proxy;
    su_free(ob->ob_home, old_proxy);
    return 0;
  }

  return -1;
}

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/* ---------------------------------------------------------------------- */

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/** Obtain contacts for REGISTER */
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int outbound_get_contacts(outbound_t *ob,
			  sip_contact_t **return_current_contact,
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			  sip_contact_t **return_previous_contact)
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{
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  if (ob) {
    if (ob->ob_contacts)
      *return_current_contact = ob->ob_rcontact;
    *return_previous_contact = ob->ob_previous;
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  }
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  return 0;
}
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/** REGISTER request has been sent */
int outbound_start_registering(outbound_t *ob)
{
  if (ob)
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    ob->ob_registering = 1;
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  return 0;
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}

/** Process response to REGISTER request */
int outbound_register_response(outbound_t *ob,
			       int terminating,
			       sip_t const *request,
			       sip_t const *response)
{
  int status, reregister;

  if (!ob)
    return 0;

  if (terminating) {
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    ob->ob_registering = ob->ob_registered = 0;
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    return 0;			/* Cleanup is done separately */
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  }
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  if (!response || !request)
    return 0;

  assert(request->sip_request); assert(response->sip_status);
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  status = response->sip_status->st_status;

  if (status < 300) {
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    if (request->sip_contact && response->sip_contact) {
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      sip_contact_t *m;

      if (ob->ob_rcontact != NULL) {
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        msg_header_free(ob->ob_home, (msg_header_t *)ob->ob_rcontact);
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        ob->ob_rcontact = NULL;
      }

      /* Ignore the contacts that were unregistered, if any */
      for (m = request->sip_contact; m; m = m->m_next) {
        if (!m->m_expires || strtoul(m->m_expires, NULL, 10) != 0)
          break;
      }
      assert (!ob->ob_registering || m != NULL);

      if (m)
        ob->ob_rcontact = (sip_contact_t *)
	  msg_header_dup_one(ob->ob_home, (const msg_header_t *)m);

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      ob->ob_registered = ob->ob_registering;
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    } else
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      ob->ob_registered = 0;
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  }
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  reregister = outbound_check_for_nat(ob, request, response);
  if (reregister)
    return reregister;

  if (ob->ob_previous && status < 300) {
    msg_header_free(ob->ob_home, (void *)ob->ob_previous);
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    ob->ob_previous = NULL;
  }

  return 0;
}


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/** @internal Check if there is a NAT between us and registrar.
 *
 * @retval -1 upon an error
 * @retval #ob_register_ok (0) if the registration was OK
 * @retval #ob_reregister (1) if client needs to re-register
 * @retval #ob_reregister_now (2) if client needs to re-register immediately
 */
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static
int outbound_check_for_nat(outbound_t *ob,
			   sip_t const *request,
			   sip_t const *response)
{
  int binding_changed;
  sip_contact_t *m = ob->ob_rcontact;

  /* Update NAT information */
  binding_changed = outbound_nat_detect(ob, request, response);

  if (!ob->ob_nat_detected)
    return ob_no_nat;

  /* Contact was set by application, do not change it */
  if (!ob->ob_by_stack)
    return ob_no_nat;

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  /* Application does not want us to do any NAT traversal */
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  if (!ob->ob_prefs.natify)
    return ob_no_nat;

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  /* We have detected NAT. Now, what to do?
   * 1) do nothing - register as usual and let proxy take care of it?
   * 2) try to detect our public nat binding and use it
   * 2A) use public vias from nta generated by STUN or UPnP
   * 2B) use SIP Via header
   */

  /* Do we have to ask for reregistration */
  if (!m || binding_changed >= ob_nat_changed) {
    if (ob->ob_stun) {
      /* Use STUN? */
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      return ob_reregister;
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    }
    else if (ob->ob_upnp) {
      /* Use UPnP */
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      return ob_reregister;
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    }
    else {
      if (outbound_contacts_from_via(ob, response->sip_via) < 0)
        return -1;
    }

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    return ob_reregister_now;
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  }

  return 0;
}

/**@internal
 *
 * Detect NAT.
 *
 * Based on "received" and possible "rport" parameters in the top-most Via,
 * check and update our NAT status.
 *
 * @retval ob_nat_changed (2) change in public NAT binding detected
 * @retval ob_nat_detected (1) NAT binding detected
 * @retval ob_no_nat (0) no NAT binding detected
 * @retval -1 an error occurred
 */
static
int outbound_nat_detect(outbound_t *ob,
			sip_t const *request,
			sip_t const *response)
{
  sip_via_t const *v;
  int one = 1;
  char const *received, *rport;
  char *nat_detected, *nat_port;
  char *new_detected, *new_port;

  assert(request && request->sip_request);
  assert(response && response->sip_status);

  if (!ob || !response || !response->sip_via || !request->sip_via)
    return -1;

  v = response->sip_via;

  received = v->v_received;
  if (!received || !strcmp(received, request->sip_via->v_host))
    return 0;

  if (!host_is_ip_address(received)) {
    if (received[0])
      SU_DEBUG_3(("outbound(%p): Via with invalid received=%s\n",
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		  (void *)ob->ob_owner, received));
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    return 0;
  }

  rport = sip_via_port(v, &one); assert(rport);

  nat_detected = ob->ob_nat_detected;
  nat_port = ob->ob_nat_port;

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  if (nat_detected && host_cmp(received, nat_detected) == 0) {
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    if (nat_port && su_casematch(rport, nat_port))
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      return 1;
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    if (!v->v_rport || !v->v_rport[0])
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      return 1;
  }

  if (!nat_detected) {
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    SU_DEBUG_5(("outbound(%p): detected NAT: %s != %s\n",
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		(void *)ob->ob_owner, v->v_host, received));
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    if (ob->ob_oo && ob->ob_oo->oo_status)
      ob->ob_oo->oo_status(ob->ob_owner, ob, 101, "NAT detected", TAG_END());
  }
  else {
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    SU_DEBUG_5(("outbound(%p): NAT binding changed: "
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		"[%s]:%s != [%s]:%s\n",
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		(void *)ob->ob_owner, nat_detected, nat_port, received, rport));
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    if (ob->ob_oo && ob->ob_oo->oo_status)
      ob->ob_oo->oo_status(ob->ob_owner, ob, 102, "NAT binding changed", TAG_END());
  }

  /* Save our nat binding */
  new_detected = su_strdup(ob->ob_home, received);
  new_port = su_strdup(ob->ob_home, rport);

  if (!new_detected || !new_port) {
    su_free(ob->ob_home, new_detected);
    su_free(ob->ob_home, new_port);
    return -1;
  }

  ob->ob_nat_detected = new_detected;
  ob->ob_nat_port = new_port;

  su_free(ob->ob_home, nat_detected);
  su_free(ob->ob_home, nat_port);

  return 2;
}

/* ---------------------------------------------------------------------- */

/** Convert "gruu" parameter returned by registrar to Contact header. */
int outbound_gruuize(outbound_t *ob, sip_t const *sip)
{
  sip_contact_t *m = NULL;
  char *gruu;

  if (!ob)
    return 0;

  if (ob->ob_rcontact == NULL)
    return -1;

  if (!ob->ob_prefs.gruuize && ob->ob_instance) {
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    char const *my_instance, *my_reg_id = NULL;
    char const *instance, *reg_id;
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    m = ob->ob_rcontact;
    my_instance = msg_header_find_param(m->m_common, "+sip.instance=");
    if (my_instance)
      my_reg_id = msg_header_find_param(m->m_common, "reg-id=");

    for (m = sip->sip_contact; m; m = m->m_next) {
      if (my_instance) {
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	instance = msg_header_find_param(m->m_common, "+sip.instance=");
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	if (!instance || strcmp(instance, my_instance))
	  continue;
	if (my_reg_id) {
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	  reg_id = msg_header_find_param(m->m_common, "reg-id=");
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	  if (!reg_id || strcmp(reg_id, my_reg_id))
	    continue;
	}
      }

      if (url_cmp_all(ob->ob_rcontact->m_url, m->m_url) == 0)
	break;
    }
  }

  if (m == NULL) {
    if (ob->ob_gruu)
      msg_header_free(ob->ob_home, (void *)ob->ob_gruu), ob->ob_gruu = NULL;
    return 0;
  }

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  gruu = (char *)msg_header_find_param(m->m_common, "pub-gruu=");
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  if (gruu == NULL || gruu[0] == '\0')
    gruu = (char *)msg_header_find_param(m->m_common, "gruu=");
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  if (gruu == NULL || gruu[0] == '\0')
    return 0;

  gruu = msg_unquote_dup(NULL, gruu);
  m = gruu ? sip_contact_format(ob->ob_home, "<%s>", gruu) : NULL;
  su_free(NULL, gruu);

  if (!m)
    return -1;

  if (ob->ob_gruu)
    msg_header_free(ob->ob_home, (void *)ob->ob_gruu);
  ob->ob_gruu = m;

  return 0;
}

/* ---------------------------------------------------------------------- */

static int create_keepalive_message(outbound_t *ob,
				    sip_t const *register_request);

static int keepalive_options(outbound_t *ob);
static int keepalive_options_with_registration_probe(outbound_t *ob);

static int response_to_keepalive_options(outbound_t *ob,
					 nta_outgoing_t *orq,
					 sip_t const *sip);
664 665 666 667 668
static int process_response_to_keepalive_options(outbound_t *ob,
						 nta_outgoing_t *orq,
						 sip_t const *sip,
						 int status,
						 char const *phrase);
669 670 671 672 673

static void keepalive_timer(su_root_magic_t *root_magic,
			    su_timer_t *t,
			    su_timer_arg_t *ob_as_timer_arg);

674
/** Start OPTIONS keepalive or contact validation process */
675 676 677
void outbound_start_keepalive(outbound_t *ob,
			      nta_outgoing_t *register_transaction)
{
678
  unsigned interval = 0;
679
  int need_to_validate, udp;
680 681 682 683

  if (!ob)
    return;

684 685 686 687 688 689 690
  udp = ob->ob_via && ob->ob_via->v_protocol == sip_transport_udp;

  if (/* ob->ob_prefs.natify && */
      /* On UDP, use OPTIONS keepalive by default */
      (udp ? ob->ob_prefs.okeepalive != 0
       /* Otherwise, only if requested */
       : ob->ob_prefs.okeepalive > 0))
691
    interval = ob->ob_prefs.interval;
692

693 694
  need_to_validate = ob->ob_prefs.validate && !ob->ob_validated;

695
  if (!register_transaction ||
696 697 698 699 700 701
      !(need_to_validate || interval != 0) ||
      /*
       * Never validated, but OPTIONS timed out
       * => retry only if application retries REGISTER
       */
      ob->ob_validate_timed_out) {
702 703 704 705 706 707 708
    outbound_stop_keepalive(ob);
    return;
  }

  if (ob->ob_keepalive.timer)
    su_timer_destroy(ob->ob_keepalive.timer), ob->ob_keepalive.timer = NULL;

709
  if (interval) {
710 711 712 713 714 715 716
    su_duration_t max_defer;

    max_defer = su_root_get_max_defer(ob->ob_root);
    if ((su_duration_t)interval >= max_defer) {
      interval -= max_defer - 100;
    }

717 718
    ob->ob_keepalive.timer =
      su_timer_create(su_root_task(ob->ob_root), interval);
719

720 721
    su_timer_deferrable(ob->ob_keepalive.timer, 1);
  }
722 723 724

  ob->ob_keepalive.interval = interval;

725
  if (!ob->ob_validated && ob->ob_keepalive.sipstun
726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762
      && 0 /* Stun is disabled for now */) {
    nta_tport_keepalive(register_transaction);
  }
  else {
    if (register_transaction) {
      msg_t *msg = nta_outgoing_getrequest(register_transaction);
      sip_t const *register_request = sip_object(msg);
      create_keepalive_message(ob, register_request);
      msg_destroy(msg);
    }

    keepalive_options(ob);
  }
}

void outbound_stop_keepalive(outbound_t *ob)
{
  if (!ob)
    return;

  ob->ob_keepalive.interval = 0;

  if (ob->ob_keepalive.timer)
    su_timer_destroy(ob->ob_keepalive.timer), ob->ob_keepalive.timer = NULL;

  if (ob->ob_keepalive.orq)
    nta_outgoing_destroy(ob->ob_keepalive.orq), ob->ob_keepalive.orq = NULL;

  if (ob->ob_keepalive.msg)
    msg_destroy(ob->ob_keepalive.msg), ob->ob_keepalive.msg = NULL;
}

/** @internal Create a message template for keepalive. */
static int create_keepalive_message(outbound_t *ob, sip_t const *regsip)
{
  msg_t *msg = nta_msg_create(ob->ob_nta, MSG_FLG_COMPACT), *previous;
  sip_t *osip = sip_object(msg);
763
  sip_contact_t *m = ob->ob_rcontact;
764 765 766

  unsigned d = ob->ob_keepalive.interval;

767 768 769
  if (msg == NULL)
    return -1;

770 771
  assert(regsip); assert(regsip->sip_request);

772 773 774 775 776 777 778 779 780 781 782 783 784 785 786
  if (m && m->m_params) {
    sip_accept_contact_t *ac;
    size_t i;
    int features = 0;

    ac = sip_accept_contact_make(msg_home(msg), "*;require;explicit");

    for (i = 0; m->m_params[i]; i++) {
      char const *s = m->m_params[i];
      if (!sip_is_callerpref(s))
	continue;
      features++;
      s = su_strdup(msg_home(msg), s);
      msg_header_add_param(msg_home(msg), ac->cp_common, s);
    }
787

788 789 790 791
    if (features)
      msg_header_insert(msg, NULL, (void *)ac);
    else
      msg_header_free(msg_home(msg), (void *)ac);
792 793
  }

794 795
  if (0 >
      /* Duplicate essential headers from REGISTER request: */
796
      sip_add_tl(msg, osip,
797 798 799 800 801 802 803 804 805 806 807 808 809
		 SIPTAG_TO(regsip->sip_to),
		 SIPTAG_FROM(regsip->sip_from),
		 /* XXX - we should only use loose routing here */
		 /* XXX - if we used strict routing,
		    the route header/request_uri must be restored
		 */
		 SIPTAG_ROUTE(regsip->sip_route),
		 /* Add Max-Forwards 0 */
		 TAG_IF(d, SIPTAG_MAX_FORWARDS_STR("0")),
		 TAG_IF(d, SIPTAG_SUBJECT_STR("KEEPALIVE")),
		 SIPTAG_CALL_ID_STR(ob->ob_cookie),
		 SIPTAG_ACCEPT_STR(outbound_content_type),
		 TAG_END()) ||
810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833
      /* Create request-line, Call-ID, CSeq */
      nta_msg_request_complete(msg,
       			nta_default_leg(ob->ob_nta),
       			SIP_METHOD_OPTIONS,
       			(void *)regsip->sip_to->a_url) < 0 ||
      msg_serialize(msg, (void *)osip) < 0 ||
      msg_prepare(msg) < 0)
    return msg_destroy(msg), -1;

  previous = ob->ob_keepalive.msg;
  ob->ob_keepalive.msg = msg;
  msg_destroy(previous);

  return 0;
}

static int keepalive_options(outbound_t *ob)
{
  msg_t *req;
  sip_t *sip;

  if (ob->ob_keepalive.orq)
    return 0;

834 835
  if (ob->ob_prefs.validate && ob->ob_registered && !ob->ob_validated
      && !ob->ob_validate_timed_out)
836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856
    return keepalive_options_with_registration_probe(ob);

  req = msg_copy(ob->ob_keepalive.msg);
  if (!req)
    return -1;
  sip = sip_object(req); assert(sip); assert(sip->sip_request);

  if (nta_msg_request_complete(req, nta_default_leg(ob->ob_nta),
			       SIP_METHOD_UNKNOWN, NULL) < 0)
    return msg_destroy(req), -1;

  if (ob->ob_keepalive.auc[0])
    auc_authorization(ob->ob_keepalive.auc, req, (void *)sip,
		      "OPTIONS", sip->sip_request->rq_url, sip->sip_payload);

  ob->ob_keepalive.orq =
    nta_outgoing_mcreate(ob->ob_nta,
			 response_to_keepalive_options,
			 ob,
			 NULL,
			 req,
857 858
			 TAG_IF(ob->ob_proxy_override,
				NTATAG_DEFAULT_PROXY(ob->ob_proxy)),
859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882
			 TAG_END());

  if (!ob->ob_keepalive.orq)
    return msg_destroy(req), -1;

  return 0;
}

static int response_to_keepalive_options(outbound_t *ob,
					 nta_outgoing_t *orq,
					 sip_t const *sip)
{
  int status = 408;
  char const *phrase = sip_408_Request_timeout;

  if (sip && sip->sip_status) {
    status = sip->sip_status->st_status;
    phrase = sip->sip_status->st_phrase;
  }

  if (status == 100) {
    /* This probably means that we are in trouble. whattodo, whattodo */
  }

883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902
  if (status >= 200) {
    if (orq == ob->ob_keepalive.orq)
      ob->ob_keepalive.orq = NULL;
    process_response_to_keepalive_options(ob, orq, sip, status, phrase);
    nta_outgoing_destroy(orq);
  }

  return 0;
}

static int process_response_to_keepalive_options(outbound_t *ob,
						 nta_outgoing_t *orq,
						 sip_t const *sip,
						 int status,
						 char const *phrase)
{
  int binding_check;
  int challenged = 0, credentials = 0;
  msg_t *_reqmsg = nta_outgoing_getrequest(orq);
  sip_t *request = sip_object(_reqmsg); msg_destroy(_reqmsg);
903

904 905 906 907 908 909 910
  if (sip == NULL) {
    SU_DEBUG_3(("outbound(%p): keepalive %u %s\n", (void *)ob->ob_owner,
		status, phrase));
    ob->ob_oo->oo_keepalive_error(ob->ob_owner, ob, status, phrase, TAG_END());
    return 0;
  }

911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939
  if (status == 401 || status == 407) {
    if (sip->sip_www_authenticate)
      challenged += auc_challenge(ob->ob_keepalive.auc,
				  ob->ob_home,
				  sip->sip_www_authenticate,
				  sip_authorization_class) > 0;
    if (sip->sip_proxy_authenticate)
      challenged += auc_challenge(ob->ob_keepalive.auc,
				  ob->ob_home,
				  sip->sip_proxy_authenticate,
				  sip_proxy_authorization_class) > 0;
    if (ob->ob_oo->oo_credentials)
      credentials = ob->ob_oo->oo_credentials(ob->ob_owner,
					      ob->ob_keepalive.auc);
  }

  binding_check = outbound_nat_detect(ob, request, sip);

  if (binding_check > 1) {
    /* Bindings have changed */
    if (outbound_contacts_from_via(ob, sip->sip_via) == 0) {
      /* XXX - Destroy old keepalive template message */

      /* re-REGISTER */
      ob->ob_oo->oo_refresh(ob->ob_owner, ob);
      return 0;
    }
  }

940
  if (binding_check <= 1 && ob->ob_registered && ob->ob_keepalive.validating) {
941 942
    int failed = 0;
    unsigned loglevel = 3;
943 944 945 946 947 948 949 950

    if (challenged > 0 && credentials > 0) {
      keepalive_options_with_registration_probe(ob);
      return 0;
    }

    if (status < 300 && ob->ob_keepalive.validated) {
      loglevel = 5;
951
      if (ob->ob_validated)
952 953 954
	loglevel = 99;		/* only once */
      ob->ob_validated = ob->ob_once_validated = 1;
    }
955 956 957 958
    else if (status == 408) {
      loglevel = 3, failed = 1;
      ob->ob_validate_timed_out = !ob->ob_once_validated;
    }
959
    else if (status == 401 || status == 407 || status == 403)
960 961 962
      loglevel = 5, failed = 1;
    else
      loglevel = 3, failed = 1;
963

964
    if (loglevel <= SU_LOG->log_level) {
965 966 967
      sip_contact_t const *m = ob->ob_rcontact;

      if  (m)
968
	su_llog(SU_LOG, loglevel,
969 970 971 972 973
		"outbound(%p): %s <" URL_PRINT_FORMAT ">\n",
		(void *)ob->ob_owner,
		failed ? "FAILED to validate" : "validated",
		URL_PRINT_ARGS(m->m_url));
      else
974
	su_llog(SU_LOG, loglevel,
975 976 977 978
		"outbound(%p): %s registration\n",
		(void *)ob->ob_owner,
		failed ? "FAILED to validate" : "validated");

979
      if (failed)
980
	su_llog(SU_LOG, loglevel, "outbound(%p): FAILED with %u %s\n",
981
		(void *)ob->ob_owner, status, phrase);
982
    }
983

984
    if (failed)
985 986 987
      ob->ob_oo->oo_probe_error(ob->ob_owner, ob, status, phrase, TAG_END());
  }
  else if (status == 408) {
988
    SU_DEBUG_3(("outbound(%p): keepalive timeout\n", (void *)ob->ob_owner));
989
    outbound_stop_keepalive(ob);
990
    ob->ob_oo->oo_keepalive_error(ob->ob_owner, ob, status, phrase, TAG_END());
991 992 993
    return 0;
  }

994
  ob->ob_keepalive.validating = 0;
995

996 997
  if (ob->ob_keepalive.timer)
    su_timer_set(ob->ob_keepalive.timer, keepalive_timer, ob);
998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037

  return 0;
}

static void keepalive_timer(su_root_magic_t *root_magic,
			    su_timer_t *t,
			    su_timer_arg_t *ob_casted_as_timer_arg)
{
  outbound_t *ob = (outbound_t *)ob_casted_as_timer_arg;

  (void)root_magic;

  if (keepalive_options(ob) < 0)
    su_timer_set(t, keepalive_timer, ob_casted_as_timer_arg);	/* XXX */
}


/** @internal Send a keepalive OPTIONS that probes the registration */
static int keepalive_options_with_registration_probe(outbound_t *ob)
{
  msg_t *req;
  sip_t *sip;
  void *request_uri;

  if (ob->ob_keepalive.orq)
    return 0;

  req = msg_copy(ob->ob_keepalive.msg);
  if (!req)
    return -1;

  sip = sip_object(req); assert(sip);
  request_uri = sip->sip_to->a_url;

  if (nta_msg_request_complete(req, nta_default_leg(ob->ob_nta),
       			SIP_METHOD_OPTIONS, request_uri) < 0)
    return msg_destroy(req), -1;

  if (ob->ob_keepalive.auc[0])
    auc_authorization(ob->ob_keepalive.auc, req, (void *)sip,
1038
		      "OPTIONS", request_uri, sip->sip_payload);
1039 1040 1041 1042 1043 1044 1045

  ob->ob_keepalive.orq =
    nta_outgoing_mcreate(ob->ob_nta,
			 response_to_keepalive_options,
			 ob,
			 NULL,
			 req,
1046 1047
			 TAG_IF(ob->ob_proxy_override,
				NTATAG_DEFAULT_PROXY(ob->ob_proxy)),
1048 1049 1050 1051 1052 1053 1054 1055 1056
			 SIPTAG_SUBJECT_STR("REGISTRATION PROBE"),
			 /* NONE is used to remove
			    Max-Forwards: 0 found in ordinary keepalives */
			 SIPTAG_MAX_FORWARDS(SIP_NONE),
			 TAG_END());

  if (!ob->ob_keepalive.orq)
    return msg_destroy(req), -1;

1057 1058 1059
  ob->ob_keepalive.validating = 1;
  ob->ob_keepalive.validated = 0;

1060 1061 1062 1063 1064 1065
  return 0;
}

/** Check if request should be processed by outbound */
int outbound_targeted_request(sip_t const *sip)
{
1066
  return
1067 1068 1069 1070
    sip && sip->sip_request &&
    sip->sip_request->rq_method == sip_method_options &&
    sip->sip_accept &&
    sip->sip_accept->ac_type &&
1071
    su_casematch(sip->sip_accept->ac_type, outbound_content_type);
1072 1073 1074
}

/** Answer to the connectivity probe OPTIONS */
1075
int outbound_process_request(outbound_t *ob,
1076 1077 1078 1079 1080 1081 1082
			     nta_incoming_t *irq,
			     sip_t const *sip)
{
  /* XXX - We assume that Call-ID is not modified. */
  if (strcmp(sip->sip_call_id->i_id, ob->ob_cookie))
    return 0;

1083
  if (ob->ob_keepalive.validating) {
1084
    SU_DEBUG_5(("outbound(%p): registration check OPTIONS received\n",
1085
		(void *)ob->ob_owner));
1086 1087 1088
    ob->ob_keepalive.validated = 1;
  }

1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101
  nta_incoming_treply(irq, SIP_200_OK,
		      SIPTAG_CONTENT_TYPE_STR(outbound_content_type),
		      SIPTAG_PAYLOAD_STR(ob->ob_cookie),
		      TAG_END());
  return 200;
}


/* ---------------------------------------------------------------------- */

/**@internal
 * Create contacts for outbound.
 *
1102
 * There are two contacts:
1103 1104 1105 1106 1107 1108 1109
 * one suitable for registrations (ob_rcontact) and another that can be used
 * in dialogs (ob_dcontact).
 */
int outbound_contacts_from_via(outbound_t *ob, sip_via_t const *via)
{
  su_home_t *home = ob->ob_home;
  sip_contact_t *rcontact, *dcontact;
1110
  char reg_id_param[20] = "";
1111 1112 1113 1114 1115 1116 1117 1118 1119
  sip_contact_t *previous_previous, *previous_rcontact, *previous_dcontact;
  sip_via_t *v, v0[1], *previous_via;
  int contact_uri_changed;

  if (!via)
    return -1;

  v = v0; *v0 = *via; v0->v_next = NULL;

1120
  dcontact = ob->ob_oo->oo_contact(ob->ob_owner, home, 1,
1121
				   v, v->v_protocol, NULL);
1122 1123 1124 1125

  if (ob->ob_instance && ob->ob_reg_id != 0)
    snprintf(reg_id_param, sizeof reg_id_param, ";reg-id=%u", ob->ob_reg_id);

1126
  rcontact = ob->ob_oo->oo_contact(ob->ob_owner, home, 0,
1127
				   v, v->v_protocol,
1128
				   ob->ob_instance, reg_id_param, NULL);
1129

1130
  v = sip_via_dup(home, v);
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147

  if (!rcontact || !dcontact || !v) {
    msg_header_free(home, (void *)dcontact);
    if (rcontact != dcontact)
      msg_header_free(home, (void *)rcontact);
    msg_header_free(home, (void *)v);
    return -1;
  }

  contact_uri_changed = !ob->ob_rcontact ||
    url_cmp_all(ob->ob_rcontact->m_url, rcontact->m_url);

  if (contact_uri_changed) {
    previous_previous = ob->ob_previous;
    previous_dcontact = ob->ob_dcontact;
    previous_via = ob->ob_via;

1148
    if (ob->ob_registered
1149 1150 1151
        /* && (ob->ob_reg_id == 0 || ob->ob_info.outbound < outbound_feature_supported)
         * XXX - multiple connections not yet supported
	 */)
1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
      previous_rcontact = NULL, ob->ob_previous = ob->ob_rcontact;
    else
      previous_rcontact = ob->ob_rcontact, ob->ob_previous = NULL;

    if (ob->ob_previous)
      msg_header_replace_param(home, (void*)ob->ob_previous, "expires=0");
  }
  else {
    previous_previous = ob->ob_rcontact;
    previous_rcontact = NULL;
    previous_dcontact = ob->ob_dcontact;
    previous_via = ob->ob_via;
  }

  ob->ob_contacts = 1;

  ob->ob_rcontact = rcontact;
  ob->ob_dcontact = dcontact;
  ob->ob_via = v;

  if (contact_uri_changed) {
    ob->ob_registering = 0;
    ob->ob_registered = 0;
    ob->ob_validated = 0;
  }

  msg_header_free(home, (void *)previous_rcontact);
  msg_header_free(home, (void *)previous_previous);
  if (previous_dcontact != ob->ob_previous &&
      previous_dcontact != previous_rcontact &&
      previous_dcontact != previous_previous)
    msg_header_free(home, (void *)previous_dcontact);
  msg_header_free(home, (void *)previous_via);

  return 0;
}

/**Set new contact.
 *
 * @retval 0 when successful
 * @retval -1 error setting contact
 */
int outbound_set_contact(outbound_t *ob,
			 sip_contact_t const *application_contact,
1196
			 sip_via_t const *v,
1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
			 int terminating)
{
  su_home_t *home = ob->ob_home;
  sip_contact_t *rcontact = NULL, *dcontact = NULL, *previous = NULL;
  sip_contact_t *m1, *m2, *m3;
  int contact_uri_changed = 0;

  m1 = ob->ob_rcontact;
  m2 = ob->ob_dcontact;
  m3 = ob->ob_previous;

  if (terminating) {
1209 1210
    if (ob->ob_by_stack && application_contact == NULL)
      return 0;
1211

1212 1213 1214 1215
    if (ob->ob_contacts)
      previous = ob->ob_rcontact;
  }
  else if (application_contact) {
1216 1217
    rcontact = sip_contact_dup(home, application_contact);

1218
    if (!ob->ob_rcontact ||
1219 1220 1221 1222 1223
	url_cmp_all(ob->ob_rcontact->m_url, application_contact->m_url)) {
      contact_uri_changed = 1;
      previous = ob->ob_contacts ? ob->ob_rcontact : NULL;
    }
  }
1224 1225 1226
  else if (ob->ob_by_stack) {
    return 0;    /* Xyzzy - nothing happens */
  }
1227
  else if (v) {
1228
    char const *tport = !v->v_next ? v->v_protocol : NULL;
1229
    char reg_id_param[20];
1230

1231
    dcontact = ob->ob_oo->oo_contact(ob->ob_owner, home, 1,
1232
				     v, tport, NULL);
1233 1234 1235
    if (!dcontact)
      return -1;

1236 1237
    if (ob->ob_instance && ob->ob_reg_id != 0)
      snprintf(reg_id_param, sizeof reg_id_param, ";reg-id=%u", ob->ob_reg_id);
1238

1239
    rcontact = ob->ob_oo->oo_contact(ob->ob_owner, home, 0,
1240
				     v, v->v_protocol,
1241
				     ob->ob_instance, reg_id_param, NULL);
1242 1243
    if (!rcontact)
      return -1;
1244

1245
    if (!ob->ob_rcontact ||
1246 1247 1248 1249
	url_cmp_all(ob->ob_rcontact->m_url, rcontact->m_url)) {
      contact_uri_changed = 1;
      previous = ob->ob_contacts ? ob->ob_rcontact : NULL;
    }
1250
  }
1251

1252 1253 1254
  if (previous)
    msg_header_replace_param(home, (msg_common_t *)previous, "expires=0");

1255 1256
  ob->ob_by_stack = application_contact == NULL;

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  ob->ob_contacts = rcontact != NULL;

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  ob->ob_rcontact = rcontact;
  ob->ob_dcontact = dcontact;
  ob->ob_previous = previous;

  if (contact_uri_changed) {
    ob->ob_registering = 0;
    ob->ob_registered = 0;
    ob->ob_validated = 0;
    ob->ob_once_validated = 0;
  }

  if (m1 != previous)
    msg_header_free(home, (void *)m1);
  if (m2 != m1 && m2 != m3)
    msg_header_free(home, (void *)m2);
  msg_header_free(home, (void *)m3);

  return 0;
}

sip_contact_t const *outbound_dialog_contact(outbound_t const *ob)
{
  if (ob == NULL)
    return NULL;
  else if (ob->ob_gruu)
    return ob->ob_gruu;
  else
    return ob->ob_dcontact;
}

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sip_contact_t const *outbound_dialog_gruu(outbound_t const *ob)
{
  return ob ? ob->ob_gruu : NULL;
}

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/* ---------------------------------------------------------------------- */


static enum outbound_feature
feature_level(sip_t const *sip, char const *tag, int level)
{
  if (sip_has_feature(sip->sip_require, tag))
    return outbound_feature_required;
  else if (sip_has_feature(sip->sip_supported, tag))
    return outbound_feature_supported;
  else if (sip_has_feature(sip->sip_unsupported, tag))
    return outbound_feature_unsupported;
  else
Kai Samposalo's avatar
Kai Samposalo committed
1307
    return (enum outbound_feature)level;
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}


void outbound_peer_info(outbound_t *ob, sip_t const *sip)
{
  if (sip == NULL) {
    ob->ob_info.outbound = outbound_feature_unsure;
    ob->ob_info.gruu = outbound_feature_unsure;
    ob->ob_info.pref = outbound_feature_unsure;
    return;
  }

  ob->ob_info.outbound = feature_level(sip, "outbound", ob->ob_info.outbound);
  ob->ob_info.gruu = feature_level(sip, "gruu", ob->ob_info.gruu);
  ob->ob_info.pref = feature_level(sip, "pref", ob->ob_info.pref);
}