receive.c

Go to the documentation of this file.

/* 
 *$Id: receive.c 5149 2008-10-31 11:12:46Z miconda $
 *
 * Copyright (C) 2001-2003 FhG Fokus
 *
 * This file is part of Kamailio, a free SIP server.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * History:
 * ---------
 * 2003-02-28 scratchpad compatibility abandoned (jiri)
 * 2003-01-29 transport-independent message zero-termination in
 *            receive_msg (jiri)
 * 2003-02-07 undoed jiri's zero term. changes (they break tcp) (andrei)
 * 2003-02-10 moved zero-term in the calling functions (udp_receive &
 *            tcp_read_req)
 * 2003-08-13 fixed exec_pre_cb returning 0 (backported from stable) (andrei)
 * 2004-02-06 added user preferences support - destroy_avps() (bogdan)
 * 2004-04-30 exec_pre_cb is called after basic sanity checks (at least one
 *            via present & parsed ok)  (andrei)
 * 2004-08-23 avp core changed - destroy_avp-> reset_avps (bogdan)
 * 2005-07-26 default onreply route added (andrei)
 * 2006-12-22 functions for script flags added (bogdan)
 */

/*! 
 * \file 
 * \brief Receive message and process routing for it
 */


#include <string.h>
#include <stdlib.h>
#include <sys/time.h>

#include "receive.h"
#include "globals.h"
#include "dprint.h"
#include "route.h"
#include "parser/msg_parser.h"
#include "forward.h"
#include "action.h"
#include "mem/mem.h"
#include "ip_addr.h"
#include "script_cb.h"
#include "dset.h"
#include "usr_avp.h"
#include "core_stats.h"


#include "tcp_server.h" /* for tcpconn_add_alias */


#ifdef DEBUG_DMALLOC
#include <mem/dmalloc.h>
#endif

static unsigned int msg_no=0;
/* address preset vars */
str default_global_address={0,0};
str default_global_port={0,0};
str default_via_address={0,0};
str default_via_port={0,0};

unsigned int get_next_msg_no(void)
{
   return ++msg_no;
}

/*!
 * \brief Receive a message and process routing for it
 *
 * Receive a message, execute pre script callbacks, run top route and execute
 * post script callbacks. Then the on_reply route is executed, and the message
 * eventual forwarded.
 * \warning buf must be 0 terminated (buf[len]=0) or some things might  break
 * (e.g.: modules/textops)
 * \param buf message
 * \param len message length
 * \param rcv_info receive informations
 * \return 0 on success, -1 on errors
 */
int receive_msg(char* buf, unsigned int len, struct receive_info* rcv_info) 
{
   struct sip_msg* msg;

   msg=pkg_malloc(sizeof(struct sip_msg));
   if (msg==0) {
      LM_ERR("no pkg mem left for sip_msg\n");
      goto error00;
   }
   msg_no++;
   /* number of vias parsed -- good for diagnostic info in replies */
   via_cnt=0;

   memset(msg,0, sizeof(struct sip_msg)); /* init everything to 0 */
   /* fill in msg */
   msg->buf=buf;
   msg->len=len;
   /* zero termination (termination of orig message bellow not that
      useful as most of the work is done with scratch-pad; -jiri  */
   /* buf[len]=0; */ /* WARNING: zero term removed! */
   msg->rcv=*rcv_info;
   msg->id=msg_no;
   msg->set_global_address=default_global_address;
   msg->set_global_port=default_global_port;
   
   if (parse_msg(buf,len, msg)!=0){
      LM_ERR("parse_msg failed\n");
      goto error02;
   }
   LM_DBG("After parse_msg...\n");


   /* ... clear branches from previous message */
   clear_branches();

   if (msg->first_line.type==SIP_REQUEST) {
      update_stat( rcv_reqs, 1);
      /* sanity checks */
      if ((msg->via1==0) || (msg->via1->error!=PARSE_OK)){
         /* no via, send back error ? */
         LM_ERR("no via found in request\n");
         update_stat( err_reqs, 1);
         goto error02;
      }
      /* check if necessary to add receive?->moved to forward_req */
      /* check for the alias stuff */
#ifdef USE_TCP
      if (msg->via1->alias && tcp_accept_aliases && 
            (((rcv_info->proto==PROTO_TCP) && !tcp_disable)
#ifdef USE_TLS
               || ((rcv_info->proto==PROTO_TLS) && !tls_disable)
#endif
            )
         ){
         if (tcpconn_add_alias(rcv_info->proto_reserved1, msg->via1->port,
                           rcv_info->proto)!=0){
            LM_ERR("tcp alias failed\n");
            /* continue */
         }
      }
#endif

      LM_DBG("preparing to run routing scripts...\n");
      /* set request route type --bogdan*/
      set_route_type( REQUEST_ROUTE );

      /* execute pre-script callbacks, if any;
       * if some of the callbacks said not to continue with
       * script processing, don't do so;
       * if we are here basic sanity checks are already done
       * (like presence of at least one via), so you can count
       * on via1 being parsed in a pre-script callback --andrei
       */
      if (exec_pre_req_cb(msg)==0 ) {
         update_stat( drp_reqs, 1);
         goto end; /* drop the message */
      }

      /* exec the routing script */
      run_top_route(rlist[DEFAULT_RT], msg);

      /* execute post request-script callbacks */
      exec_post_req_cb(msg);
   } else if (msg->first_line.type==SIP_REPLY) {
      update_stat( rcv_rpls, 1);
      /* sanity checks */
      if ((msg->via1==0) || (msg->via1->error!=PARSE_OK)){
         /* no via, send back error ? */
         LM_ERR("no via found in reply\n");
         update_stat( err_rpls, 1);
         goto error02;
      }

      /* set reply route type --bogdan*/
      set_route_type( ONREPLY_ROUTE );

      /* execute pre-script callbacks, if any ;
       * if some of the callbacks said not to continue with
       * script processing, don't do so ;
       * if we are here, basic sanity checks are already done
       * (like presence of at least one via), so you can count
       * on via1 being parsed in a pre-script callback --andrei
       */
      if (exec_pre_rpl_cb(msg)==0 ) {
         update_stat( drp_rpls, 1);
         goto end; /* drop the reply */
      }

      /* exec the onreply routing script */
      if ( onreply_rlist[DEFAULT_RT]!=0 &&
      (run_top_route(onreply_rlist[DEFAULT_RT],msg)&ACT_FL_DROP) ) {
         LM_DBG("dropping reply %d\n", msg->REPLY_STATUS);
         update_stat( drp_rpls, 1);
         goto end; /* drop the message */
      } else {
         /* send the msg */
         forward_reply(msg);
         /* TODO - TX reply stat */
      }

      /* execute post reply-script callbacks */
      exec_post_rpl_cb(msg);
   }

end:
   /* free possible loaded avps -bogdan */
   reset_avps();
   LM_DBG("cleaning up\n");
   free_sip_msg(msg);
   pkg_free(msg);
   return 0;
error02:
   free_sip_msg(msg);
   pkg_free(msg);
error00:
   return -1;
}

---