nta.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) 2005 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 nta.c
 * @brief Sofia SIP Transaction API implementation
 * 
 * This source file has been divided into sections as follows:
 * 1) agent
 * 2) tport handling
 * 3) dispatching messages received from network
 * 4) message creation and message utility functions
 * 5) stateless operation
 * 6) dialogs (legs)
 * 7) server transactions (incoming)
 * 8) client transactions (outgoing)
 * 9) resolving URLs for client transactions
 * 10) 100rel reliable responses (reliable)
 * 11) SigComp handling and public transport interface
 * 
 * @author Pekka Pessi <[e-mail]>
 * 
 * @date Created: Tue Jun 13 02:57:51 2000 ppessi
 */

#include "config.h"

#include <sofia-sip/string0.h>

/** @internal SU message argument structure type */
#define SU_MSG_ARG_T   union sm_arg_u
/** @internal SU timer argument pointer type */
#define SU_TIMER_ARG_T struct nta_agent_s

#include <sofia-sip/su_alloc.h>
#include <sofia-sip/su.h>
#include <sofia-sip/su_time.h>
#include <sofia-sip/su_wait.h>
#include <sofia-sip/su_tagarg.h>

#include <sofia-sip/base64.h>
#include <sofia-sip/su_uniqueid.h>

#include <sofia-sip/sip.h>
#include <sofia-sip/sip_header.h>
#include <sofia-sip/sip_util.h>
#include <sofia-sip/sip_status.h>

#include <sofia-sip/hostdomain.h>

#include <sofia-sip/msg_addr.h>
#include <sofia-sip/msg_parser.h>

#include "nta_internal.h"
#include "sofia-sip/nta_stateless.h"
#include "sofia-sip/url_tag.h"

#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>
#include <limits.h>
#include <errno.h>

/* From AM_INIT/AC_INIT in our "config.h" */
char const nta_version[] = PACKAGE_VERSION;

#if HAVE_FUNC
#elif HAVE_FUNCTION
#define __func__ __FUNCTION__
#else
static char const __func__[] = "nta";
#endif

#define NONE ((void *)-1)

/* Internal tags */

/* Delay sending of request */
#define NTATAG_DELAY_SENDING(x) ntatag_delay_sending, tag_bool_v((x))
#define NTATAG_DELAY_SENDING_REF(x) \
ntatag_delay_sending_ref, tag_bool_vr(&(x))

extern tag_typedef_t ntatag_delay_sending;
extern tag_typedef_t ntatag_delay_sending_ref;

/* Allow sending incomplete responses */
#define NTATAG_INCOMPLETE(x) ntatag_incomplete, tag_bool_v((x))
#define NTATAG_INCOMPLETE_REF(x) \
ntatag_incomplete_ref, tag_bool_vr(&(x))

extern tag_typedef_t ntatag_incomplete;
extern tag_typedef_t ntatag_incomplete_ref;

nta_compressor_vtable_t *nta_compressor_vtable = NULL;

/* Agent */
static int agent_tag_init(nta_agent_t *self);
static int agent_timer_init(nta_agent_t *agent);
static void agent_timer(su_root_magic_t *rm, su_timer_t *, nta_agent_t *);
static int agent_launch_terminator(nta_agent_t *agent);
static void agent_kill_terminator(nta_agent_t *agent);
static int agent_set_params(nta_agent_t *agent, tagi_t *tags);
static void agent_set_udp_params(nta_agent_t *self, usize_t udp_mtu);
static int agent_get_params(nta_agent_t *agent, tagi_t *tags);

/* Transport interface */
static sip_via_t const *agent_tport_via(tport_t *tport);
static int outgoing_insert_via(nta_outgoing_t *orq, sip_via_t const *);
static int nta_tpn_by_via(tp_name_t *tpn, sip_via_t const *v, int *using_rport);

static msg_t *nta_msg_create_for_transport(nta_agent_t *agent, int flags,
					   char const data[], usize_t dlen,
					   tport_t const *tport,
					   tp_client_t *via);

static int complete_response(msg_t *response, 
			     int status, char const *phrase, 
			     msg_t *request);

#define IF_SIGCOMP_TPTAG_COMPARTMENT(cc)     TAG_IF(cc, TPTAG_COMPARTMENT(cc)),
#define IF_SIGCOMP_TPTAG_COMPARTMENT_REF(cc) TPTAG_COMPARTMENT_REF(cc),

struct sigcomp_compartment;

struct sigcomp_compartment *
nta_compartment_ref(struct sigcomp_compartment *cc);

static
struct sigcomp_compartment *
agent_compression_compartment(nta_agent_t *sa, tport_t *tp, tp_name_t const *tpn,
			      int new_if_needed);

static
int agent_accept_compressed(nta_agent_t *sa, msg_t *msg,
			    struct sigcomp_compartment *cc);

static int agent_close_compressor(nta_agent_t *sa,
				  struct sigcomp_compartment *cc);

static int agent_zap_compressor(nta_agent_t *sa,
				struct sigcomp_compartment *cc);


static char const * stateful_branch(su_home_t *home, nta_agent_t *);
static char const * stateless_branch(nta_agent_t *, msg_t *, sip_t const *,
				    tp_name_t const *tp);

#define NTA_BRANCH_PRIME SU_U64_C(0xB9591D1C361C6521)
#define NTA_TAG_PRIME    SU_U64_C(0xB9591D1C361C6521)

#ifndef UINT32_MAX
#define UINT32_MAX (0xffffffffU)
#endif

HTABLE_PROTOS_WITH(leg_htable, lht, nta_leg_t, size_t, hash_value_t);
static nta_leg_t *leg_find(nta_agent_t const *sa,
			   char const *method_name,
			   url_t const *request_uri,
			   sip_call_id_t const *i,
			   char const *from_tag,
			   char const *to_tag);
static nta_leg_t *dst_find(nta_agent_t const *sa, url_t const *u0,
			   char const *method);
static void leg_recv(nta_leg_t *, msg_t *, sip_t *, tport_t *);
static void leg_free(nta_agent_t *sa, nta_leg_t *leg);

#define NTA_HASH(i, cs) ((i)->i_hash + 26839U * (uint32_t)(cs))

HTABLE_PROTOS_WITH(incoming_htable, iht, nta_incoming_t, size_t, hash_value_t);
static nta_incoming_t *incoming_create(nta_agent_t *agent,
				       msg_t *request,
				       sip_t *sip,
				       tport_t *tport,
				       char const *tag);
static int incoming_callback(nta_leg_t *leg, nta_incoming_t *irq, sip_t *sip);
static void incoming_free(nta_incoming_t *irq);
su_inline void incoming_cut_off(nta_incoming_t *irq);
su_inline void incoming_reclaim(nta_incoming_t *irq);
static void incoming_queue_init(incoming_queue_t *, 
				unsigned timeout);
static void incoming_queue_adjust(nta_agent_t *sa, 
				  incoming_queue_t *queue, 
				  unsigned timeout);

static nta_incoming_t *incoming_find(nta_agent_t const *agent,
				     sip_t const *sip,
				     sip_via_t const *v,
				     nta_incoming_t **merge,
				     nta_incoming_t **ack,
				     nta_incoming_t **cancel);
static int incoming_reply(nta_incoming_t *irq, msg_t *msg, sip_t *sip);
su_inline int incoming_recv(nta_incoming_t *irq, msg_t *msg, sip_t *sip,
				tport_t *tport);
su_inline int incoming_ack(nta_incoming_t *irq, msg_t *msg, sip_t *sip,
			       tport_t *tport);
su_inline int incoming_cancel(nta_incoming_t *irq, msg_t *msg, sip_t *sip,
				  tport_t *tport);
static void request_merge(nta_agent_t *,
			  msg_t *msg, sip_t *sip, tport_t *tport,
			  char const *to_tag);
su_inline int incoming_timestamp(nta_incoming_t *, msg_t *, sip_t *);
static void incoming_timer(nta_agent_t *);

static nta_reliable_t *reliable_mreply(nta_incoming_t *,
				       nta_prack_f *, nta_reliable_magic_t *,
				       msg_t *, sip_t *);
static int reliable_send(nta_incoming_t *, nta_reliable_t *, msg_t *, sip_t *);
static int reliable_final(nta_incoming_t *irq, msg_t *msg, sip_t *sip);
static msg_t *reliable_response(nta_incoming_t *irq);
static nta_reliable_t *reliable_find(nta_agent_t const *, sip_t const *);
static int reliable_recv(nta_reliable_t *rel, msg_t *, sip_t *, tport_t *);
static void reliable_flush(nta_incoming_t *irq);
static void reliable_timeout(nta_incoming_t *irq, int timeout);

HTABLE_PROTOS_WITH(outgoing_htable, oht, nta_outgoing_t, size_t, hash_value_t);
static nta_outgoing_t *outgoing_create(nta_agent_t *agent,
				       nta_response_f *callback,
				       nta_outgoing_magic_t *magic,
				       url_string_t const *route_url,
				       tp_name_t const *tpn,
				       msg_t *msg,
				       tag_type_t tag, tag_value_t value, ...);
static void outgoing_queue_init(outgoing_queue_t *, 
				unsigned timeout);
static void outgoing_queue_adjust(nta_agent_t *sa, 
				  outgoing_queue_t *queue, 
				  unsigned timeout);
static void outgoing_free(nta_outgoing_t *orq);
su_inline void outgoing_cut_off(nta_outgoing_t *orq);
su_inline void outgoing_reclaim(nta_outgoing_t *orq);
static nta_outgoing_t *outgoing_find(nta_agent_t const *sa,
				     msg_t const *msg,
				     sip_t const *sip,
				     sip_via_t const *v);
static int outgoing_recv(nta_outgoing_t *orq, int status, msg_t *, sip_t *);
static void outgoing_default_recv(nta_outgoing_t *, int, msg_t *, sip_t *);
static void outgoing_timer(nta_agent_t *);
static int outgoing_recv_reliable(nta_outgoing_t *orq, msg_t *msg, sip_t *sip);

/* Internal message passing */
union sm_arg_u {
  struct outgoing_recv_s {
    nta_outgoing_t *orq;
    msg_t          *msg;
    sip_t          *sip;
    int             status;
  } a_outgoing_recv[1];

  incoming_queue_t a_incoming_queue[1];
  outgoing_queue_t a_outgoing_queue[1];
};

/* Global module data */

/**@var char const NTA_DEBUG[];
 *
 * Environment variable determining the default debug log level.
 *
 * The NTA_DEBUG environment variable is used to determine the default
 * debug logging level. The normal level is 3.
 * 
 * @sa <sofia-sip/su_debug.h>, #su_log_global, #SOFIA_DEBUG
 */
#ifdef DOXYGEN
extern char const NTA_DEBUG[]; /* dummy declaration for Doxygen */
#endif

#ifndef SU_DEBUG
#define SU_DEBUG 3
#endif

/**Debug log for @b nta module. 
 * 
 * The nta_log is the log object used by @b nta module. The level of
 * nta_log is set using #NTA_DEBUG environment variable.
 */
su_log_t nta_log[] = { SU_LOG_INIT("nta", "NTA_DEBUG", SU_DEBUG) };

/* ====================================================================== */
/* 1) Agent */

/**
 * Create an NTA agent object.
 *
 * Create an NTA agent object.  The agent
 * object creates and binds a server socket with address specified in @e url.
 * If the @e host portion of the @e url is @c "*", the agent listens to all
 * addresses available on the host.
 *
 * When a message is received, the agent object parses it.  If the result is
 * a valid SIP message, the agent object passes the message to the
 * application by invoking the nta_message_f @e callback function.
 *
 * @note
 * The @e url can be either parsed url (of type url_t ()), or a valid
 * SIP URL as a string.
 *
 * @note
 * If @e url is @c NULL, the default @e url @c "sip:*" is used.
 * @par
 * If @e url is @c NONE (iow, (void*)-1), no server sockets are bound.
 * @par
 * If @p transport parameters are specified in @a url, agent uses only
 * specified transport type.
 *
 * @par
 * If an @p maddr parameter is specified in @e url, agent binds to the
 * specified address, but uses @e host part of @e url when it generates
 * @Contact and @Via headers. The @p maddr parameter is also included,
 * unless it equals to @c INADDR_ANY (@p 0.0.0.0 or @p [::]).
 *
 * @param root          pointer to a su_root_t used for synchronization
 * @param contact_url   URL that agent uses to bind the server sockets
 * @param callback      pointer to callback function
 * @param magic         pointer to user data
 * @param tag,value,... tagged arguments
 *
 * @TAGS
 * NTATAG_ALIASES(),
 * NTATAG_BAD_REQ_MASK(), NTATAG_BAD_RESP_MASK(), NTATAG_BLACKLIST(),
 * NTATAG_CANCEL_2543(), NTATAG_CANCEL_487(), NTATAG_CLIENT_RPORT(),
 * NTATAG_DEBUG_DROP_PROB(), NTATAG_DEFAULT_PROXY(),
 * NTATAG_EXTRA_100(), NTATAG_GRAYLIST(),
 * NTATAG_MAXSIZE(), NTATAG_MAX_FORWARDS(), NTATAG_MERGE_482(), NTATAG_MCLASS()
 * NTATAG_PASS_100(), NTATAG_PASS_408(), NTATAG_PRELOAD(), NTATAG_PROGRESS(), 
 * NTATAG_REL100(), 
 * NTATAG_SERVER_RPORT(),
 * NTATAG_SIPFLAGS(),
 * NTATAG_SIP_T1X64(), NTATAG_SIP_T1(), NTATAG_SIP_T2(), NTATAG_SIP_T4(),
 * NTATAG_STATELESS(),
 * NTATAG_TAG_3261(), NTATAG_TCP_RPORT(), NTATAG_TIMEOUT_408(),
 * NTATAG_TIMER_C(), NTATAG_MAX_PROCEEDING(),
 * NTATAG_UA(), NTATAG_UDP_MTU(), NTATAG_USER_VIA(),
 * NTATAG_USE_NAPTR(), NTATAG_USE_SRV() and NTATAG_USE_TIMESTAMP().
 *
 * @note The value from following tags are stored, but they currently do nothing:
 * NTATAG_SIGCOMP_ALGORITHM(), NTATAG_SIGCOMP_OPTIONS(), NTATAG_SMIME()
 *
 * @note It is possible to provide @c (url_string_t*)-1 as @a contact_url. 
 * In that case, no server sockets are bound.
 * 
 * @retval handle to the agent when successful,
 * @retval NULL upon an error.
 *
 * @sa NUTAG_
 */
nta_agent_t *nta_agent_create(su_root_t *root,
			      url_string_t const *contact_url,
			      nta_message_f *callback,
			      nta_agent_magic_t *magic,
			      tag_type_t tag, tag_value_t value, ...)
{
  nta_agent_t *agent;
  ta_list ta;

  if (root == NULL)
    return su_seterrno(EINVAL), NULL;

  ta_start(ta, tag, value);

  if ((agent = su_home_new(sizeof(*agent)))) {
    unsigned timer_c;

    agent->sa_root = root;
    agent->sa_callback = callback;
    agent->sa_magic = magic;
    agent->sa_flags = MSG_DO_CANONIC;

    agent->sa_maxsize         = 2 * 1024 * 1024; /* 2 MB */
    agent->sa_bad_req_mask    = 
      /*
       * Bit-wise not of these - what is left is suitable for UAs with 
       * 100rel, timer, events, publish 
       */
      (unsigned) ~(sip_mask_response | sip_mask_proxy | sip_mask_registrar | 
		   sip_mask_pref | sip_mask_privacy);
    agent->sa_bad_resp_mask   = 
      (unsigned) ~(sip_mask_request | sip_mask_proxy | sip_mask_registrar | 
		   sip_mask_pref | sip_mask_privacy);
    agent->sa_t1 	      = NTA_SIP_T1;
    agent->sa_t2 	      = NTA_SIP_T2;
    agent->sa_t4              = NTA_SIP_T4;
    agent->sa_t1x64 	      = 64 * NTA_SIP_T1;
    agent->sa_timer_c         = 185 * 1000;
    agent->sa_graylist        = 600;
    agent->sa_drop_prob       = 0;
    agent->sa_is_a_uas        = 0;
    agent->sa_progress        = 60 * 1000;
    agent->sa_user_via        = 0;
    agent->sa_extra_100       = 0;
    agent->sa_pass_100        = 0;
    agent->sa_timeout_408     = 1;
    agent->sa_pass_408        = 0;
    agent->sa_merge_482       = 0;
    agent->sa_cancel_2543     = 0;
    agent->sa_cancel_487      = 1;
    agent->sa_invite_100rel   = 0;
    agent->sa_timestamp       = 0;
    agent->sa_use_naptr       = 1;
    agent->sa_use_srv         = 1;
    agent->sa_auto_comp       = 0;
    agent->sa_server_rport    = 1;

    /* RFC 3261 section 8.1.1.6 */
    sip_max_forwards_init(agent->sa_max_forwards);

    if (getenv("SIPCOMPACT"))
      agent->sa_flags |= MSG_DO_COMPACT;