cr_func.c

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/*
 * $Id: cr_func.c 5497 2009-01-22 13:43:17Z henningw $
 *
 * Copyright (C) 2007-2008 1&1 Internet AG
 *
 * 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
 */

/**
 * \file cr_func.c
 * \brief Routing and balancing functions.
 * \ingroup carrierroute
 * - Module; \ref carrierroute
 */

#include <ctype.h>
#include <assert.h>
#include <stdlib.h>
#include "cr_func.h"
#include "cr_db.h"
#include "../../sr_module.h"
#include "../../action.h"
#include "../../parser/parse_uri.h"
#include "../../parser/parse_from.h"
#include "../../ut.h"
#include "../../parser/digest/digest.h"
#include "../../parser/hf.h"
#include "../../mem/mem.h"
#include "../../qvalue.h"
#include "../../dset.h"
#include "cr_map.h"
#include "cr_rule.h"
#include "cr_domain.h"
#include "cr_carrier.h"
#include "carrierroute.h"


enum hash_algorithm {
   alg_crc32 = 1, /*!< hashing algorithm is CRC32 */
   alg_prime, /*!< hashing algorithm is (right 18 digits of hash_source % prime_number) % max_targets + 1 */
   alg_error
};


static const str SIP_URI  = { .s="sip:",  .len=4 };
static const str SIPS_URI = { .s="sips:", .len=5 };
static const str AT_SIGN  = { .s="@",     .len=1 };


/**
 * Get the id that belongs to a string name from gparam_t structure.
 *
 * Get the id that belongs to a string name from gparam_t structure, use the
 * search_id function for the lookup.
 * @param _msg SIP message
 * @param gp id as integer, pseudo-variable or AVP name of carrier
 * @param map lookup function
 * @param size size of the list
 * @return id on success, -1 otherwise
 */
static inline int cr_gp2id(struct sip_msg *_msg, gparam_t *gp, struct name_map_t *map, int size) {
   int id;
   struct usr_avp *avp;
   int_str avp_val;
   str tmp;

   switch (gp->type) {
   case GPARAM_TYPE_INT:
      return gp->v.ival;
      break;
   case GPARAM_TYPE_PVE:
      /* does this PV hold an AVP? */
      if (gp->v.pve->spec.type==PVT_AVP) {
         avp = search_first_avp(gp->v.pve->spec.pvp.pvn.u.isname.type,
                  gp->v.pve->spec.pvp.pvn.u.isname.name, &avp_val, 0);
         if (!avp) {
            LM_ERR("cannot find AVP '%.*s'\n", gp->v.pve->spec.pvp.pvn.u.isname.name.s.len,
                  gp->v.pve->spec.pvp.pvn.u.isname.name.s.s);
            return -1;
         }
         if ((avp->flags&AVP_VAL_STR)==0) {
            return avp_val.n;
         } else {
            id = map_name2id(map, size, &avp_val.s);
            if (id < 0) {
               LM_ERR("could not find id '%.*s' from AVP\n",
                     gp->v.pve->spec.pvp.pvn.u.isname.name.s.len,
                     gp->v.pve->spec.pvp.pvn.u.isname.name.s.s);
               return -1;
            }
            return id;
         }
      } else {
         /* retrieve name from parameter */
         if (fixup_get_svalue(_msg, gp, &tmp)<0) {
            LM_ERR("cannot print the name from PV\n");
            return -1;
         }
         id = map_name2id(map, size, &tmp);
         if (id < 0) {
            LM_ERR("could not find id '%.*s' from PV\n", tmp.len, tmp.s);
            return -1;
         }
         return id;
      }
   default:
      LM_ERR("invalid parameter type\n");
      return -1;
   }
}


/**
 * Try to match the reply code rc to the reply code with wildcards.
 *
 * @param rcw reply code specifier with wildcards
 * @param rc the current reply code
 *
 * @return 0 on match, -1 otherwise
 */
static inline int reply_code_matcher(const str *rcw, const str *rc) {
   int i;
   
   if (rcw->len==0) return 0;
   
   if (rcw->len != rc->len) return -1;
   
   for (i=0; i<rc->len; i++) {
      if (rcw->s[i]!='.' && rcw->s[i]!=rc->s[i]) return -1;
   }
   
   return 0;
}


/**
 * writes the next_domain avp using the rule list of failure_tree
 *
 * @param frr_head the head of the failure route rule list
 * @param host last tried host
 * @param reply_code the last reply code
 * @param flags flags for the failure route rule
 * @param dstavp the name of the AVP where to store the next domain
 *
 * @return 0 on success, -1 on failure
 */
static int set_next_domain_on_rule(struct failure_route_rule *frr_head,
      const str *host, const str *reply_code, const flag_t flags,
      const gparam_t *dstavp) {
   struct failure_route_rule * rr;
   int_str avp_val;
   
   assert(frr_head != NULL);
   
   LM_DBG("searching for matching routing rules");
   for (rr = frr_head; rr != NULL; rr = rr->next) {
      /*
      LM_DBG("rr.flags=%d rr.mask=%d flags=%d\n", rr->flags, rr->mask, flags);
      LM_DBG("rr.host.len=%d host.len=%d\n", rr->host.len, host->len);
      LM_DBG("rr.host.s='%.*s' host.s='%.*s'\n", rr->host.len, rr->host.s, host->len, host->s);
      LM_DBG("rr.reply_code.len=%d reply_code.len=%d\n", rr->reply_code.len, reply_code->len);
      LM_DBG("rr.reply_code.s='%.*s' reply_code.s='%.*s'\n", rr->reply_code.len, rr->reply_code.s, reply_code->len, reply_code->s);
      */
      if (((rr->mask & flags) == rr->flags) &&
            ((rr->host.len == 0) || (str_strcmp(host, &rr->host)==0)) &&
            (reply_code_matcher(&(rr->reply_code), reply_code)==0)) {
         avp_val.n = rr->next_domain;
         if (add_avp(dstavp->v.pve->spec.pvp.pvn.u.isname.type,
               dstavp->v.pve->spec.pvp.pvn.u.isname.name, avp_val)<0) {
            LM_ERR("set AVP failed\n");
            return -1;
         }
         
         LM_INFO("next_domain is %d\n", rr->next_domain);
         return 0;
      }
   }
   
   LM_INFO("no matching rule for (flags=%d, host='%.*s', reply_code='%.*s') found\n", flags, host->len, host->s, reply_code->len, reply_code->s);
   return -1;
}


/**
 * traverses the failure routing tree until a matching rule is found.
 * The longest match is taken, so it is possible to define
 * failure route rules for a single number
 *
 * @param failure_node the current routing tree node
 * @param uri the uri to be rewritten at the current position
 * @param host last tried host
 * @param reply_code the last reply code
 * @param flags flags for the failure route rule
 * @param dstavp the name of the AVP where to store the next domain
 *
 * @return 0 on success, -1 on failure, 1 on no more matching child node and no rule list
 */
static int set_next_domain_recursor(struct dtrie_node_t *failure_node,
      const str *uri, const str *host, const str *reply_code, const flag_t flags,
      const gparam_t *dstavp) {
   str re_uri = *uri;
   void **ret;
   
   /* Skip over non-digits.  */
   while (re_uri.len > 0 && (!isdigit(*re_uri.s) && cr_match_mode == 10)) {
      ++re_uri.s;
      --re_uri.len;
   }
   ret = dtrie_longest_match(failure_node, re_uri.s, re_uri.len, NULL, cr_match_mode);

   if (ret == NULL) {
      LM_INFO("URI or prefix tree nodes empty, empty rule list\n");
      return 1;
   }
   else return set_next_domain_on_rule(*ret, host, reply_code, flags, dstavp);
}


/**
 * searches for a rule int rt with hash_index prob - 1
 * If the rule with the desired hash index is deactivated,
 * the next working rule is used.
 *
 * @param rf the route_flags node to search for rule
 * @param prob the hash index
 *
 * @return pointer to route rule on success, NULL on failure
 */
static struct route_rule * get_rule_by_hash(const struct route_flags * rf,
      const int prob) {
   struct route_rule * act_hash = NULL;

   if (prob > rf->rule_num) {
      LM_WARN("too large desired hash, taking highest\n");
      act_hash = rf->rules[rf->rule_num - 1];
   }
   act_hash = rf->rules[prob - 1];

   if (!act_hash->status) {
      if (act_hash->backup && act_hash->backup->rr) {
         act_hash = act_hash->backup->rr;
      } else {
         act_hash = NULL;
      }
   }
   LM_INFO("desired hash was %i, return %i\n", prob, act_hash ? act_hash->hash_index : -1);
   return act_hash;
}


/**
 * does the work for rewrite_on_rule, writes the new URI into dest
 *
 * @param rs the route rule used for rewriting
 * @param dest the returned new destination URI
 * @param msg the sip message
 * @param user the localpart of the uri to be rewritten
 * @param descavp the name of the AVP where the description is stored
 *
 * @return 0 on success, -1 on failure
 *
 * @see rewrite_on_rule()
 */
static int actually_rewrite(const struct route_rule *rs, str *dest,
      const struct sip_msg *msg, const str * user, gparam_t *descavp) {
   size_t len;
   char *p;
   int_str avp_val;
   int strip = 0;

   strip = (rs->strip > user->len ? user->len : rs->strip);
   strip = (strip < 0 ? 0 : strip);

   len = rs->local_prefix.len + user->len + rs->local_suffix.len +
         AT_SIGN.len + rs->host.len - strip;
   if (msg->parsed_uri.type == SIPS_URI_T) {
      len += SIPS_URI.len;
   } else {
      len += SIP_URI.len;
   }
   dest->len = 0;
   dest->s = (char *)pkg_malloc(len + 1);
   if (dest->s == NULL) {
      PKG_MEM_ERROR;
      return -1;
   }
   dest->len = len;
   p = dest->s;
   if (msg->parsed_uri.type == SIPS_URI_T) {
      memcpy(p, SIPS_URI.s, SIPS_URI.len);
      p += SIPS_URI.len;
   } else {
      memcpy(p, SIP_URI.s, SIP_URI.len);
      p += SIP_URI.len;
   }
   if (user->len) {
      memcpy(p, rs->local_prefix.s, rs->local_prefix.len);
      p += rs->local_prefix.len;
      memcpy(p, user->s + strip, user->len - strip);
      p += user->len - strip;
      memcpy(p, rs->local_suffix.s, rs->local_suffix.len);
      p += rs->local_suffix.len;
      memcpy(p, AT_SIGN.s, AT_SIGN.len);
      p += AT_SIGN.len;
   }
   /* this could be an error, or a blacklisted destination */
   if (rs->host.len == 0) {
      *p = '\0';
      pkg_free(dest->s);
      return -1;
   }
   memcpy(p, rs->host.s, rs->host.len);
   p += rs->host.len;
   *p = '\0';

   if (descavp) {
      avp_val.s = rs->comment;
      if (add_avp(AVP_VAL_STR | descavp->v.pve->spec.pvp.pvn.u.isname.type,
               descavp->v.pve->spec.pvp.pvn.u.isname.name, avp_val)<0) {
         LM_ERR("set AVP failed\n");
         pkg_free(dest->s);
         return -1;
      }
   }

   return 0;
}


/**
 * writes the uri dest using the flags and rule list of rf_head
 *
 * @param rf_head the head of the route flags list
 * @param flags user defined flags
 * @param dest the returned new destination URI
 * @param msg the sip message
 * @param user the localpart of the uri to be rewritten
 * @param hash_source the SIP header used for hashing
 * @param alg the algorithm used for hashing
 * @param dstavp the name of the destination AVP where the used host name is stored
 *
 * @return 0 on success, -1 on failure, 1 on empty rule list
 */
static int rewrite_on_rule(struct route_flags *rf_head, flag_t flags, str * dest,
      struct sip_msg * msg, const str * user, const enum hash_source hash_source,
      const enum hash_algorithm alg, gparam_t *dstavp) {
   struct route_flags * rf;
   struct route_rule * rr;
   int prob;

   assert(rf_head != NULL);

   LM_DBG("searching for matching routing rules");
   for (rf = rf_head; rf != NULL; rf = rf->next) {
      /* LM_DBG("actual flags %i, searched flags %i, mask %i and match %i", rf->flags, flags, rf->mask, flags&rf->mask); */
      if ((flags&rf->mask) == rf->flags) break;
   }

   if (rf==NULL) {
      LM_INFO("did not find a match for flags %d\n", flags);
      return -1;
   }

   if (rf->rule_list == NULL) {
      LM_INFO("empty rule list\n");
      return 1;
   }

   switch (alg) {
      case alg_prime:
         if ((prob = prime_hash_func(msg, hash_source, rf->max_targets)) < 0) {
            LM_ERR("could not hash message with prime algorithm");
            return -1;
         }
         if ((rr = get_rule_by_hash(rf, prob)) == NULL) {
            LM_CRIT("no route found\n");
            return -1;
         }
         break;
      case alg_crc32:
         if(rf->dice_max == 0) {
            LM_ERR("invalid dice_max value\n");
            return -1;
         }
         if ((prob = hash_func(msg, hash_source, rf->dice_max)) < 0) {
            LM_ERR("could not hash message with CRC32");
            return -1;
         }
         /* This auto-magically takes the last rule if anything is broken.
          * Sometimes the hash result is zero. If the first rule is off
          * (has a probablility of zero) then it has also a dice_to of
          * zero and the message could not be routed at all if we use
          * '<' here. Thus the '<=' is necessary.
          */
         for (rr = rf->rule_list;
                 rr->next != NULL && rr->dice_to <= prob;
              rr = rr->next) {}
         if (!rr->status) {
            if (!rr->backup) {
               LM_ERR("all routes are off\n");
               return -1;
            } else {
               if (!rr->backup->rr) {
                  LM_ERR("all routes are off\n");
                  return -1;
               }
               rr = rr->backup->rr;
            }
         }
         break;
      default: 
         LM_ERR("invalid hash algorithm\n");
         return -1;
   }
   return actually_rewrite(rr, dest, msg, user, dstavp);
}


/**
 * traverses the routing tree until a matching rule is found
 * The longest match is taken, so it is possible to define
 * route rules for a single number
 *
 * @param node the current routing tree node
 * @param pm the user to be used for prefix matching
 * @param flags user defined flags
 * @param dest the returned new destination URI
 * @param msg the sip message
 * @param user the localpart of the uri to be rewritten
 * @param hash_source the SIP header used for hashing
 * @param alg the algorithm used for hashing
 * @param dstavp the name of the destination AVP where the used host name is stored
 *
 * @return 0 on success, -1 on failure, 1 on no more matching child node and no rule list
 */
static int rewrite_uri_recursor(struct dtrie_node_t * node,
      const str * pm, flag_t flags, str * dest, struct sip_msg * msg, const str * user,
      const enum hash_source hash_source, const enum hash_algorithm alg,
      gparam_t *dstavp) {
   str re_pm = *pm;
   void **ret;
   
   /* Skip over non-digits.  */
   while (re_pm.len > 0 && (!isdigit(*re_pm.s) && cr_match_mode == 10)) {
      ++re_pm.s;
      --re_pm.len;
   }
   ret = dtrie_longest_match(node, re_pm.s, re_pm.len, NULL, cr_match_mode);

   if (ret == NULL) {
      LM_INFO("URI or prefix tree nodes empty, empty rule list\n");
      return 1;
   }
   else return rewrite_on_rule(*ret, flags, dest, msg, user, hash_source, alg, dstavp);
}


/**
 * rewrites the request URI of msg after determining the
 * new destination URI
 *
 * @param _msg the current SIP message
 * @param _carrier the requested carrier
 * @param _domain the requested routing domain
 * @param _prefix_matching the user to be used for prefix matching
 * @param _rewrite_user the localpart of the URI to be rewritten
 * @param _hsrc the SIP header used for hashing
 * @param _halg the hash algorithm used for hashing
 * @param _dstavp the name of the destination AVP where the used host name is stored
 *
 * @return 1 on success, -1 on failure
 */
int cr_do_route(struct sip_msg * _msg, gparam_t *_carrier,
      gparam_t *_domain, gparam_t *_prefix_matching,
      gparam_t *_rewrite_user, enum hash_source _hsrc,
      enum hash_algorithm _halg, gparam_t *_dstavp) {

   int carrier_id, domain_id, ret = -1;
   str rewrite_user, prefix_matching, dest;
   flag_t flags;
   struct route_data_t * rd;
   struct carrier_data_t * carrier_data;
   struct domain_data_t * domain_data;
   struct action act;

   if (fixup_get_svalue(_msg, _rewrite_user, &rewrite_user)<0) {
      LM_ERR("cannot print the rewrite_user\n");
      return -1;
   }

   if (fixup_get_svalue(_msg, _prefix_matching, &prefix_matching)<0) {
      LM_ERR("cannot print the prefix_matching\n");
      return -1;
   }

   flags = _msg->flags;

   do {
      rd = get_data();
   } while (rd == NULL);

   carrier_id = cr_gp2id(_msg, _carrier, rd->carrier_map, rd->carrier_num);
   if (carrier_id < 0) {
      LM_ERR("invalid carrier id %d\n", carrier_id);
      release_data(rd);
      return -1;
   }

   domain_id = cr_gp2id(_msg, _domain, rd->domain_map, rd->domain_num);
   if (domain_id < 0) {
      LM_ERR("invalid domain id %d\n", domain_id);
      release_data(rd);
      return -1;
   }
   
   carrier_data=NULL;
   if (carrier_id < 0) {
      if (fallback_default) {
         LM_NOTICE("invalid tree id %i specified, using default tree\n", carrier_id);
         carrier_data = get_carrier_data(rd, rd->default_carrier_id);
      }
   } else if (carrier_id == 0) {
      carrier_data = get_carrier_data(rd, rd->default_carrier_id);
   } else {
      carrier_data = get_carrier_data(rd, carrier_id);
      if (carrier_data == NULL) {
         if (fallback_default) {
            LM_NOTICE("invalid tree id %i specified, using default tree\n", carrier_id);
            carrier_data = get_carrier_data(rd, rd->default_carrier_id);
         }
      }
   }
   if (carrier_data == NULL) {
      LM_ERR("cannot get carrier data\n");
      goto unlock_and_out;
   }

   domain_data = get_domain_data(carrier_data, domain_id);
   if (domain_data == NULL) {
      LM_ERR("desired routing domain doesn't exist, prefix %.*s, carrier %d, domain %d\n",
         prefix_matching.len, prefix_matching.s, carrier_id, domain_id);
      goto unlock_and_out;
   }

   if (rewrite_uri_recursor(domain_data->tree, &prefix_matching, flags, &dest, _msg, &rewrite_user, _hsrc, _halg, _dstavp) != 0) {
      /* this is not necessarily an error, rewrite_recursor does already some error logging */
      LM_INFO("rewrite_uri_recursor doesn't complete, uri %.*s, carrier %d, domain %d\n", prefix_matching.len,
         prefix_matching.s, carrier_id, domain_id);
      goto unlock_and_out;
   }

   LM_INFO("uri %.*s was rewritten to %.*s, carrier %d, domain %d\n", rewrite_user.len, rewrite_user.s, dest.len, dest.s, carrier_id, domain_id);

   act.type = SET_URI_T;
   act.elem[0].type= STRING_ST;
   act.elem[0].u.string = dest.s;
   act.next = NULL;

   ret = do_action(&act, _msg);
   if (ret < 0) {
      LM_ERR("Error in do_action()\n");
   }
   pkg_free(dest.s);

unlock_and_out:
   release_data(rd);
   return ret;
}


/**
 * Loads user carrier from subscriber table and stores it in an AVP.
 *
 * @param _msg the current SIP message
 * @param _user the user to determine the carrier data
 * @param _domain the domain to determine the domain data
 * @param _dstavp the name of the AVP where to store the carrier id
 *
 * @return 1 on success, -1 on failure
 */
int cr_load_user_carrier(struct sip_msg * _msg, gparam_t *_user, gparam_t *_domain, gparam_t *_dstavp) {
   str user, domain;
   int_str avp_val;
   
   if (fixup_get_svalue(_msg, _user, &user)<0) {
      LM_ERR("cannot print the user\n");
      return -1;
   }

   if (fixup_get_svalue(_msg, _domain, &domain)<0) {
      LM_ERR("cannot print the domain\n");
      return -1;
   }
   
   /* get carrier id */
   if ((avp_val.n = load_user_carrier(&user, &domain)) < 0) {
      LM_ERR("error in load user carrier");
      return -1;
   } else {
      /* set avp */
      if (add_avp(_dstavp->v.pve->spec.pvp.pvn.u.isname.type,
               _dstavp->v.pve->spec.pvp.pvn.u.isname.name, avp_val)<0) {
         LM_ERR("add AVP failed\n");
         return -1;
      }
   }
   return 1;
}


/**
 * rewrites the request URI of msg after determining the
 * new destination URI with the crc32 hash algorithm.
 *
 * @param _msg the current SIP message
 * @param _carrier the requested carrier
 * @param _domain the requested routing domain
 * @param _prefix_matching the user to be used for prefix matching
 * @param _rewrite_user the localpart of the URI to be rewritten
 * @param _hsrc the SIP header used for hashing
 * @param _dstavp the name of the destination AVP where the used host name is stored
 *
 * @return 1 on success, -1 on failure
 */
int cr_route(struct sip_msg * _msg, gparam_t *_carrier,
      gparam_t *_domain, gparam_t *_prefix_matching,
      gparam_t *_rewrite_user, enum hash_source _hsrc,
      gparam_t *_dstavp)
{
   return cr_do_route(_msg, _carrier, _domain, _prefix_matching,
      _rewrite_user, _hsrc, alg_crc32, _dstavp);
}


/**
 * rewrites the request URI of msg after determining the
 * new destination URI with the prime hash algorithm.
 *
 * @param _msg the current SIP message
 * @param _carrier the requested carrier
 * @param _domain the requested routing domain
 * @param _prefix_matching the user to be used for prefix matching
 * @param _rewrite_user the localpart of the URI to be rewritten
 * @param _hsrc the SIP header used for hashing
 * @param _dstavp the name of the destination AVP where the used host name is stored
 *
 * @return 1 on success, -1 on failure
 */
int cr_prime_route(struct sip_msg * _msg, gparam_t *_carrier,
      gparam_t *_domain, gparam_t *_prefix_matching,
      gparam_t *_rewrite_user, enum hash_source _hsrc,
      gparam_t *_dstavp)
{
   return cr_do_route(_msg, _carrier, _domain, _prefix_matching,
      _rewrite_user, _hsrc, alg_prime, _dstavp);
}


/**
 * Loads next domain from failure routing table and stores it in an AVP.
 *
 * @param _msg the current SIP message
 * @param _carrier the requested carrier
 * @param _domain the requested routing domain
 * @param _prefix_matching the user to be used for prefix matching
 * @param _host the host name to be used for rule matching
 * @param _reply_code the reply code to be used for rule matching
 * @param _dstavp the name of the destination AVP
 *
 * @return 1 on success, -1 on failure
 */
int cr_load_next_domain(struct sip_msg * _msg, gparam_t *_carrier,
      gparam_t *_domain, gparam_t *_prefix_matching,
      gparam_t *_host, gparam_t *_reply_code, gparam_t *_dstavp) {

   int carrier_id, domain_id, ret = -1;
   str prefix_matching, host, reply_code;
   flag_t flags;
   struct route_data_t * rd;
   struct carrier_data_t * carrier_data;
   struct domain_data_t * domain_data;

   if (fixup_get_svalue(_msg, _prefix_matching, &prefix_matching)<0) {
      LM_ERR("cannot print the prefix_matching\n");
      return -1;
   }
   if (fixup_get_svalue(_msg, _host, &host)<0) {
      LM_ERR("cannot print the host\n");
      return -1;
   }
   if (fixup_get_svalue(_msg, _reply_code, &reply_code)<0) {
      LM_ERR("cannot print the reply_code\n");
      return -1;
   }

   flags = _msg->flags;

   do {
      rd = get_data();
   } while (rd == NULL);
   
   carrier_id = cr_gp2id(_msg, _carrier, rd->carrier_map, rd->carrier_num);
   if (carrier_id < 0) {
      LM_ERR("invalid carrier id %d\n", carrier_id);
      release_data(rd);
      return -1;
   }

   domain_id = cr_gp2id(_msg, _domain, rd->domain_map, rd->domain_num);
   if (domain_id < 0) {
      LM_ERR("invalid domain id %d\n", domain_id);
      release_data(rd);
      return -1;
   }

   carrier_data=NULL;
   if (carrier_id < 0) {
      if (fallback_default) {
         LM_NOTICE("invalid tree id %i specified, using default tree\n", carrier_id);
         carrier_data = get_carrier_data(rd, rd->default_carrier_id);
      }
   } else if (carrier_id == 0) {
      carrier_data = get_carrier_data(rd, rd->default_carrier_id);
   } else {
      carrier_data = get_carrier_data(rd, carrier_id);
      if (carrier_data == NULL) {
         if (fallback_default) {
            LM_NOTICE("invalid tree id %i specified, using default tree\n", carrier_id);
            carrier_data = get_carrier_data(rd, rd->default_carrier_id);
         }
      }
   }
   if (carrier_data == NULL) {
      LM_ERR("cannot get carrier data\n");
      goto unlock_and_out;
   }

   domain_data = get_domain_data(carrier_data, domain_id);
   if (domain_data == NULL) {
      LM_ERR("desired routing domain doesn't exist, prefix %.*s, carrier %d, domain %d\n",
         prefix_matching.len, prefix_matching.s, carrier_id, domain_id);
      goto unlock_and_out;
   }

   if (set_next_domain_recursor(domain_data->failure_tree, &prefix_matching, &host, &reply_code, flags, _dstavp) != 0) {
      LM_INFO("set_next_domain_recursor doesn't complete, prefix '%.*s', carrier %d, domain %d\n", prefix_matching.len,
         prefix_matching.s, carrier_id, domain_id);
      goto unlock_and_out;
   }
   
   ret = 1;
   
unlock_and_out:
   release_data(rd);
   return ret;
}