dlg_req_within.c

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/*
 * $Id: dlg_req_within.c 5529 2009-01-28 21:51:20Z miconda $
 *
 * Copyright (C) 2007 Voice System SRL
 *
 * 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:
 * --------
 * 2007-07-10  initial version (ancuta)
 * 2008-04-04  added direction reporting in dlg callbacks (bogdan)
*/

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

#include "../../dprint.h"
#include "../../ut.h"
#include "../../db/db.h"
#include "../../dprint.h"
#include "../../config.h"
#include "../../socket_info.h"
#include "../tm/dlg.h"
#include "../tm/tm_load.h"
#include "../../mi/tree.h"
#include "dlg_timer.h"
#include "dlg_hash.h"
#include "dlg_req_within.h"
#include "dlg_db_handler.h"


#define MAX_FWD_HDR        "Max-Forwards: " MAX_FWD CRLF
#define MAX_FWD_HDR_LEN    (sizeof(MAX_FWD_HDR) - 1)

extern str dlg_extra_hdrs;



int free_tm_dlg(dlg_t *td)
{
   if(td)
   {
      if(td->route_set)
         free_rr(&td->route_set);
      pkg_free(td);
   }
   return 0;
}



dlg_t * build_dlg_t(struct dlg_cell * cell, int dir){

   dlg_t* td = NULL;
   str cseq;
   unsigned int loc_seq;

   td = (dlg_t*)pkg_malloc(sizeof(dlg_t));
   if(!td){
   
      LM_ERR("out of pkg memory\n");
      return NULL;
   }
   memset(td, 0, sizeof(dlg_t));

   /*local sequence number*/
   cseq = (dir == DLG_CALLER_LEG) ? cell->cseq[DLG_CALLEE_LEG]:
                              cell->cseq[DLG_CALLER_LEG];
   if(str2int(&cseq, &loc_seq) != 0){
      LM_ERR("invalid cseq\n");
      goto error;
   }
   /*we don not increase here the cseq as this will be done by TM*/
   td->loc_seq.value = loc_seq;
   td->loc_seq.is_set = 1;

   /*route set*/
   if( cell->route_set[dir].s && cell->route_set[dir].len){
      
      if( parse_rr_body(cell->route_set[dir].s, cell->route_set[dir].len, 
                  &td->route_set) !=0){
         LM_ERR("failed to parse route set\n");
         goto error;
      }
   } 

   /*remote target--- Request URI*/
   if(cell->contact[dir].s==0 || cell->contact[dir].len==0){

      LM_ERR("no contact available\n");
      goto error;
   }
   td->rem_target = cell->contact[dir];

   td->rem_uri =   (dir == DLG_CALLER_LEG)?  cell->from_uri: cell->to_uri;
   td->loc_uri =  (dir == DLG_CALLER_LEG)?   cell->to_uri: cell->from_uri;
   td->id.call_id = cell->callid;
   td->id.rem_tag = cell->tag[dir];
   td->id.loc_tag = (dir == DLG_CALLER_LEG) ?   cell->tag[DLG_CALLEE_LEG]:
                                    cell->tag[DLG_CALLER_LEG];
   
   td->state= DLG_CONFIRMED;
   td->send_sock = cell->bind_addr[dir];

   return td;

error:
   free_tm_dlg(td);
   return NULL;
}



/*callback function to handle responses to the BYE request */
void bye_reply_cb(struct cell* t, int type, struct tmcb_params* ps){

   struct dlg_cell* dlg;
   int event, old_state, new_state, unref, ret;

   if(ps->param == NULL || *ps->param == NULL){
      LM_ERR("invalid parameter\n");
      return;
   }

   if(ps->code < 200){
      LM_DBG("receiving a provisional reply\n");
      return;
   }

   LM_DBG("receiving a final reply %d\n",ps->code);

   dlg = (struct dlg_cell *)(*(ps->param));
   event = DLG_EVENT_REQBYE;
   next_state_dlg(dlg, event, &old_state, &new_state, &unref);


   if(new_state == DLG_STATE_DELETED && old_state != DLG_STATE_DELETED){

      LM_DBG("removing dialog with h_entry %u and h_id %u\n", 
         dlg->h_entry, dlg->h_id);

      /* 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("inconsitent 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 {
         unref++;
      }
      /* dialog terminated (BYE) */
      run_dlg_callbacks( DLGCB_TERMINATED, dlg, ps->req, DLG_DIR_NONE, 0);

      LM_DBG("first final reply\n");
      /* derefering the dialog */
      unref_dlg(dlg, unref+1);

      if_update_stat( dlg_enable_stats, active_dlgs, -1);
   }

   if(new_state == DLG_STATE_DELETED && old_state == DLG_STATE_DELETED ) {
      /* trash the dialog from DB and memory */
      LM_DBG("second final reply\n");
      /* delete the dialog from DB */
      if (dlg_db_mode)
         remove_dialog_from_db(dlg);
      /* force delete from mem */
      unref_dlg(dlg, 1);
   }

}



static inline int build_extra_hdr(struct dlg_cell * cell, str *extra_hdrs,
      str *str_hdr)
{
   char *p;

   str_hdr->len = MAX_FWD_HDR_LEN + dlg_extra_hdrs.len;
   if(extra_hdrs && extra_hdrs->len>0)
      str_hdr->len += extra_hdrs->len;

   str_hdr->s = (char*)pkg_malloc( str_hdr->len * sizeof(char) );
   if(!str_hdr->s){
      LM_ERR("out of pkg memory\n");
      goto error;
   }

   memcpy(str_hdr->s , MAX_FWD_HDR, MAX_FWD_HDR_LEN );
   p = str_hdr->s + MAX_FWD_HDR_LEN;
   if (dlg_extra_hdrs.len) {
      memcpy( p, dlg_extra_hdrs.s, dlg_extra_hdrs.len);
      p += dlg_extra_hdrs.len;
   }
   if (extra_hdrs && extra_hdrs->len>0)
      memcpy( p, extra_hdrs->s, extra_hdrs->len);

   return 0;

error: 
   return -1;
}



/* cell- pointer to a struct dlg_cell
 * dir- direction: the request will be sent to:
 *       DLG_CALLER_LEG (0): caller
 *       DLG_CALLEE_LEG (1): callee
 */
static inline int send_bye(struct dlg_cell * cell, int dir, str *hdrs)
{
   /*verify direction*/
   dlg_t* dialog_info;
   str met = {"BYE", 3};
   int result;

   if ((dialog_info = build_dlg_t(cell, dir)) == 0){
      LM_ERR("failed to create dlg_t\n");
      goto err;
   }

   LM_DBG("sending BYE to %s\n", (dir==DLG_CALLER_LEG)?"caller":"callee");

   ref_dlg(cell, 1);

   result = d_tmb.t_request_within
      (&met,         /* method*/
      hdrs,         /* extra headers*/
      NULL,          /* body*/
      dialog_info,   /* dialog structure*/
      bye_reply_cb,  /* callback function*/
      (void*)cell);  /* callback parameter*/

   if(result < 0){
      LM_ERR("failed to send the BYE request\n");
      goto err1;
   }

   free_tm_dlg(dialog_info);

   LM_DBG("BYE sent to %s\n", (dir==0)?"caller":"callee");
   return 0;

err1:
   unref_dlg(cell, 1);
err:
   if(dialog_info)
      free_tm_dlg(dialog_info);
   return -1;
}



/*parameters from MI: h_entry, h_id of the requested dialog*/
struct mi_root * mi_terminate_dlg(struct mi_root *cmd_tree, void *param ){

   struct mi_node* node;
   unsigned int h_entry, h_id;
   struct dlg_cell * dlg = NULL;
   str mi_extra_hdrs = {NULL,0};
   int status, msg_len;
   char *msg;


   if( d_table ==NULL)
      goto end;

   node = cmd_tree->node.kids;
   h_entry = h_id = 0;

   if (node==NULL || node->next==NULL)
      return init_mi_tree( 400, MI_MISSING_PARM_S, MI_MISSING_PARM_LEN);

   if (!node->value.s|| !node->value.len|| strno2int(&node->value,&h_entry)<0)
      goto error;

   node = node->next;
   if ( !node->value.s || !node->value.len || strno2int(&node->value,&h_id)<0)
      goto error;

   if (node->next) {
      node = node->next;
      if (node->value.len && node->value.s)
         mi_extra_hdrs = node->value;
   }

   LM_DBG("h_entry %u h_id %u\n", h_entry, h_id);

   dlg = lookup_dlg(h_entry, h_id);

   // lookup_dlg has incremented the reference count

   if(dlg){
      if(dlg_bye_all(dlg,(mi_extra_hdrs.len>0)?&mi_extra_hdrs:NULL)<0) {
         status = 500;
         msg = MI_DLG_OPERATION_ERR;
         msg_len = MI_DLG_OPERATION_ERR_LEN;
      } else {
         status = 200;
         msg = MI_OK_S;
         msg_len = MI_OK_LEN;
      }

      unref_dlg(dlg, 1);

      return init_mi_tree(status, msg, msg_len);
   }

end:
   return init_mi_tree(404, MI_DIALOG_NOT_FOUND, MI_DIALOG_NOT_FOUND_LEN);
   
error:
   return init_mi_tree( 400, MI_BAD_PARM_S, MI_BAD_PARM_LEN);

}

int dlg_bye(struct dlg_cell *dlg, str *hdrs, int side)
{
   str all_hdrs = { 0, 0 };
   int ret;

   if(side==DLG_CALLER_LEG)
   {
      if(dlg->dflags&DLG_FLAG_CALLERBYE)
         return -1;
      dlg->dflags |= DLG_FLAG_CALLERBYE;
   } else {
      if(dlg->dflags&DLG_FLAG_CALLEEBYE)
         return -1;
      dlg->dflags |= DLG_FLAG_CALLEEBYE;
   }
   if ((build_extra_hdr(dlg, hdrs, &all_hdrs)) != 0)
   {
      LM_ERR("failed to build dlg headers\n");
      return -1;
   }
   ret = send_bye(dlg, side, &all_hdrs);
   pkg_free(all_hdrs.s);
   return ret;
}

int dlg_bye_all(struct dlg_cell *dlg, str *hdrs)
{
   str all_hdrs = { 0, 0 };
   int ret;

   if ((build_extra_hdr(dlg, hdrs, &all_hdrs)) != 0)
   {
      LM_ERR("failed to build dlg headers\n");
      return -1;
   }

   ret = send_bye(dlg, DLG_CALLER_LEG, &all_hdrs);
   ret |= send_bye(dlg, DLG_CALLEE_LEG, &all_hdrs);
   
   pkg_free(all_hdrs.s);
   return ret;

}