cr_data.c

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/*
 * $Id: cr_data.c 5227 2008-11-19 13:16:15Z 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_data.c
 * \brief Contains the functions to manage routing data.
 * \ingroup carrierroute
 * - Module; \ref carrierroute
 */

#include <stdlib.h>
#include "../../mem/shm_mem.h"
#include "cr_data.h"
#include "carrierroute.h"
#include "cr_config.h"
#include "cr_db.h"
#include "cr_carrier.h"
#include "cr_domain.h"
#include "cr_rule.h"


/**
 * Pointer to the routing data.
 */
struct route_data_t ** global_data = NULL;


static int carrier_data_fixup(struct route_data_t * rd){
   int i;
   str tmp;
   tmp = default_tree;
   rd->default_carrier_id = -1;
   for(i=0; i<rd->carrier_num; i++){
      if(rd->carriers[i]){
         if(str_strcmp(rd->carriers[i]->name, &tmp) == 0){
            rd->default_carrier_id = rd->carriers[i]->id;
         }
      }
   }
   if(rd->default_carrier_id < 0){
      LM_ERR("default_carrier not found\n");
   }
   return 0;
}


/**
 * initialises the routing data, initialises the global data pointer
 *
 * @return 0 on success, -1 on failure
 */
int init_route_data(void) {
   if (global_data == NULL) {
      global_data = (struct route_data_t **)
                    shm_malloc(sizeof(struct route_data_t *));
      if (global_data == NULL) {
         SHM_MEM_ERROR;
         return -1;
      }
   }
   *global_data = NULL;
   return 0;
}


/**
 * Frees the routing data
 */
void destroy_route_data(void){
   struct route_data_t * rd = get_data();
   clear_route_data(rd);
   if(global_data){
      *global_data = NULL;
      shm_free(global_data);
      global_data = NULL;
   }
}


/**
 * Clears the complete routing data.
 *
 * @param data route data to be cleared
 */
void clear_route_data(struct route_data_t *data) {
   int i;

   if (data == NULL) {
      return;
   }
   if (data->carriers != NULL) {
      for (i = 0; i < data->carrier_num; ++i) {
         if (data->carriers[i] != NULL) {
            destroy_carrier_data(data->carriers[i]);
         }
      }
      shm_free(data->carriers);
   }
   if (data->carrier_map) {
      for (i = 0; i < data->carrier_num; ++i) {
         if (data->carrier_map[i].name.s) shm_free(data->carrier_map[i].name.s);
      }
      shm_free(data->carrier_map);
   }
   if (data->domain_map) {
      for (i = 0; i < data->domain_num; ++i) {
         if (data->domain_map[i].name.s) shm_free(data->domain_map[i].name.s);
      }
      shm_free(data->domain_map);
   }
   shm_free(data);
   return;
}


/**
 * adds a carrier_data struct for given carrier.
 *
 * @param rd route data to be searched
 * @param carrier_data the carrier data struct to be inserted
 *
 * @return 0 on success, -1 on failure
 */
int add_carrier_data(struct route_data_t * rd, struct carrier_data_t * carrier_data) {
   if (rd->first_empty_carrier >= rd->carrier_num) {
      LM_ERR("carrier array already full");
      return -1;
   }

   if (rd->carriers[rd->first_empty_carrier] != 0) {
      LM_ERR("invalid pointer in first empty carrier entry");
      return -1;
   }

   rd->carriers[rd->first_empty_carrier] = carrier_data;
   rd->first_empty_carrier++;
   return 0;
}


/**
 * Loads the routing data into the routing trees and sets the
 * global_data pointer to the new data. The old_data is removed
 * when it is not locked anymore.
 *
 * @return 0 on success, -1 on failure
 */
int reload_route_data(void) {
   struct route_data_t * old_data;
   struct route_data_t * new_data = NULL;
   int i;

   if ((new_data = shm_malloc(sizeof(struct route_data_t))) == NULL) {
      SHM_MEM_ERROR;
      return -1;
   }
   memset(new_data, 0, sizeof(struct route_data_t));

   switch (mode) {
   case CARRIERROUTE_MODE_DB:
      if (load_route_data_db(new_data) < 0) {
         LM_ERR("could not load routing data\n");
         goto errout;
      }
      break;
   case CARRIERROUTE_MODE_FILE:
      if (load_config(new_data) < 0) {
         LM_ERR("could not load routing data\n");
         goto errout;
      }
      break;
   default:
      LM_ERR("invalid mode");
      goto errout;
   }
   if (new_data == NULL) {
      LM_ERR("loading routing data failed (NULL pointer)");
      goto errout;
   }

   /* sort carriers by id for faster access */
   qsort(new_data->carriers, new_data->carrier_num, sizeof(new_data->carriers[0]), compare_carrier_data);

   /* sort domains by id for faster access */
   for (i=0; i<new_data->carrier_num; i++) {
      qsort(new_data->carriers[i]->domains, new_data->carriers[i]->domain_num, sizeof(new_data->carriers[i]->domains[0]), compare_domain_data);
   }

   if (rule_fixup(new_data) < 0) {
      LM_ERR("could not fixup rules\n");
      goto errout;
   }

   if (carrier_data_fixup(new_data) < 0){
      LM_ERR("could not fixup trees\n");
      goto errout;
   }

   new_data->proc_cnt = 0;

   if (*global_data == NULL) {
      *global_data = new_data;
   } else {
      old_data = *global_data;
      *global_data = new_data;
      i = 0;
      while (old_data->proc_cnt > 0) {
         LM_ERR("data is still locked after %i seconds\n", i);
         sleep_us(i*1000000);
         i++;
      }
      clear_route_data(old_data);
   }
   return 0;

 errout:
   clear_route_data(new_data);
   return -1;
}


/**
 * Increases lock counter and returns a pointer to the
 * current routing data
 *
 * @return pointer to the global routing data on success,
 * NULL on failure
*/
struct route_data_t * get_data(void) {
   struct route_data_t *ret;
   if (!global_data || !*global_data) {
      return NULL;
   }
   ret = *global_data;
   lock_get(&ret->lock);
   ++ret->proc_cnt;
   lock_release(&ret->lock);
   if (ret == *global_data) {
      return ret;
   } else {
      lock_get(&ret->lock);
      --ret->proc_cnt;
      lock_release(&ret->lock);
      return NULL;
   }
}


/**
 * decrements the lock counter of the routing data
 *
 * @param data data to be released
 */
void release_data(struct route_data_t *data) {
   lock_get(&data->lock);
   --data->proc_cnt;
   lock_release(&data->lock);
}


/**
 * Returns the carrier data for the given id by doing a binary search.
 * @note The carrier array must be sorted!
 *
 * @param rd route data to be searched
 * @param carrier_id the id of the desired carrier
 *
 * @return a pointer to the desired carrier data, NULL if not found.
 */
struct carrier_data_t *get_carrier_data(struct route_data_t * rd, int carrier_id) {
   struct carrier_data_t **ret;
   struct carrier_data_t key;
   struct carrier_data_t *pkey = &key;

   if (!rd) {
      LM_ERR("NULL pointer in parameter\n");
      return NULL;
   }
   key.id = carrier_id;
   ret = bsearch(&pkey, rd->carriers, rd->carrier_num, sizeof(rd->carriers[0]), compare_carrier_data);
   if (ret) return *ret;
   return NULL;
}


typedef int (*cmpfunc_t)(const void *v1, const void *v2);


/**
 * Implements a binary search algorithm using the function cmpfunc
 * for comparison.
 *
 * @param base pointer to the beginning of the array
 * @param len length of array
 * @param elemsize size of array elements
 * @param key pointer to the key we are looking for
 * @param cmpfunc function to be used for comparison
 * @param index  If index is not NULL it is set to:
 *     -1 if an error occured,
 *     the index of the first entry equal to v
 *     or the index of the first entry greater than v in the case v was not found.
 *   Be careful: The index returned can be greater than the length of the array!
 *
 * @return -1 on error, 0 if the value was not found, 1 if it was found.
 */
static int binary_search(void *base, unsigned int len, int elemsize, void *key, cmpfunc_t cmpfunc, int *index) {
   int left, right, mid;

   if (index) *index=-1;
   if (!base) {
      LM_ERR("NULL pointer in parameter\n");
      return -1;
   }
   if (len == 0) {
      if (index) *index=0;
      return 0;
   }

   left=0;
   right=len-1;
   if (cmpfunc(base+elemsize*left, key) > 0) {
      LM_DBG("not found (out of left bound)\n");
      if (index) *index=0; /* not found, must be inserted at the beginning of array */
      return 0;
   }
   if (cmpfunc(base+elemsize*right, key) < 0) {
      LM_DBG("not found (out of right bound)\n");
      if (index) *index=len; /* not found, must be inserted at the end of array */
      return 0;
   }

   while (left < right) {
      mid = left + ((right - left) / 2);
      if (cmpfunc(base+elemsize*mid, key) < 0) left = mid + 1;
      else right = mid;
   }

   /* left == right here! */
   if (index) *index=left;
   if (cmpfunc(base+elemsize*left, key) == 0) return 1;
   else return 0;
}


/**
 * Returns the domain data for the given id by doing a binary search.
 * If not found, a new domain data structure is added.
 *
 * @param rd route data to used for name - id mapping
 * @param carrier_data carrier data to be searched
 * @param domain_id the id of desired domain
 *
 * @return a pointer to the desired domain data, NULL on error.
 */
static struct domain_data_t * get_domain_data_or_add(struct route_data_t * rd, struct carrier_data_t * carrier_data, int domain_id) {
   struct domain_data_t key;
   struct domain_data_t *pkey = &key;
   struct domain_data_t *domain_data = NULL;
   str *domain_name;
   int i;
   int res;

   if ((!rd) || (!carrier_data)) {
      LM_ERR("NULL pointer in parameter\n");
      return NULL;
   }

   key.id = domain_id;
   res = binary_search(carrier_data->domains, carrier_data->first_empty_domain, sizeof(struct domain_data_t *), &pkey, compare_domain_data, &i);
   if (res<0) {
      LM_ERR("error while searching for domain_id %d\n", domain_id);
      return NULL;
   }
   else if (res>0) {
      /* found domain id */
      domain_data = carrier_data->domains[i];
   }
   else {
      /* did not find domain id - insert new entry! */
      if ((domain_name = map_id2name(rd->domain_map, rd->domain_num, domain_id)) == NULL) {
         LM_ERR("could not find domain name for id %d\n", domain_id);
         return NULL;
      }
      if ((domain_data = create_domain_data(domain_id, domain_name)) == NULL) {
         LM_ERR("could not create new domain data\n");
         return NULL;
      }

      /* keep the array sorted! */
      if (add_domain_data(carrier_data, domain_data, i) < 0) {
         LM_ERR("could not add domain data\n");
         destroy_domain_data(domain_data);
         return NULL;
      }
      LM_INFO("added domain %d '%.*s' to carrier %d '%.*s'", domain_id, domain_name->len, domain_name->s, carrier_data->id, carrier_data->name->len, carrier_data->name->s);
   }

   return domain_data;
}


/**
 * Adds the given route information to the routing domain identified by
 * domain. scan_prefix identifies the number for which the information
 * is and the rewrite_* parameters define what to do in case of a match.
 * prob gives the probability with which this rule applies if there are
 * more than one for a given prefix.
 *
 * @param rd the route data to which the route shall be added
 * @param carrier_id the carrier id of the route to be added
 * @param domain_id the routing domain id of the new route
 * @param scan_prefix the number prefix
 * @param flags user defined flags
 * @param mask mask for user defined flags
 * @param max_targets the number of targets
 * @param prob the weight of the rule
 * @param rewrite_hostpart the rewrite_host of the rule
 * @param strip the number of digits to be stripped off userpart before prepending prefix
 * @param rewrite_local_prefix the rewrite prefix
 * @param rewrite_local_suffix the rewrite suffix
 * @param status the status of the rule
 * @param hash_index the hash index of the rule
 * @param backup indicates if the route is backed up by another. only 
                 useful if status==0, if set, it is the hash value
                 of another rule
 * @param backed_up an -1-termintated array of hash indices of the route 
                    for which this route is backup
 * @param comment a comment for the route rule
 *
 * @return 0 on success, -1 on error in which case it LOGs a message.
 */
int add_route(struct route_data_t * rd, int carrier_id,
      int domain_id, const str * scan_prefix, flag_t flags, flag_t mask, int max_targets,
      double prob, const str * rewrite_hostpart, int strip,
      const str * rewrite_local_prefix, const str * rewrite_local_suffix,
      int status, int hash_index, int backup, int * backed_up, const str * comment) {
   struct carrier_data_t * carrier_data = NULL;
   struct domain_data_t * domain_data = NULL;
   LM_INFO("adding prefix %.*s, prob %f\n", scan_prefix->len, scan_prefix->s, prob);

   if ((carrier_data = get_carrier_data(rd, carrier_id)) == NULL) {
      LM_ERR("could not retrieve carrier data for carrier id %d\n", carrier_id);
      return -1;
   }

   if ((domain_data = get_domain_data_or_add(rd, carrier_data, domain_id)) == NULL) {
      LM_ERR("could not retrieve domain data\n");
      return -1;
   }

   LM_INFO("found carrier and domain, now adding route\n");
   return add_route_to_tree(domain_data->tree, scan_prefix, flags, mask, scan_prefix, max_targets, prob, rewrite_hostpart,
                            strip, rewrite_local_prefix, rewrite_local_suffix, status,
                            hash_index, backup, backed_up, comment);
}


/**
 * Adds the given failure route information to the failure routing domain identified by
 * domain. scan_prefix, host, reply_code and flags identifies the number for which
 * the information is and the next_domain parameter defines where to continue routing
 * in case of a match.
 *
 * @param rd the route data to which the route shall be added
 * @param carrier_id the carrier id of the route to be added
 * @param domain_id the routing domain id of the new route
 * @param scan_prefix the number prefix
 * @param host the hostname last tried
 * @param reply_code the reply code 
 * @param flags user defined flags
 * @param mask for user defined flags
 * @param next_domain_id continue routing with this domain id
 * @param comment a comment for the failure route rule
 *
 * @return 0 on success, -1 on error in which case it LOGs a message.
 */
int add_failure_route(struct route_data_t * rd, int carrier_id, int domain_id,
      const str * scan_prefix, const str * host, const str * reply_code,
      flag_t flags, flag_t mask, int next_domain_id, const str * comment) {
   struct carrier_data_t * carrier_data = NULL;
   struct domain_data_t * domain_data = NULL;
   LM_INFO("adding prefix %.*s, reply code %.*s\n", scan_prefix->len, scan_prefix->s, reply_code->len, reply_code->s);
      
   if (reply_code->len!=3) {
      LM_ERR("invalid reply_code '%.*s'!\n", reply_code->len, reply_code->s);
      return -1;
   }
   
   if ((carrier_data = get_carrier_data(rd, carrier_id)) == NULL) {
      LM_ERR("could not retrieve carrier data\n");
      return -1;
   }
   
   if ((domain_data = get_domain_data_or_add(rd, carrier_data, domain_id)) == NULL) {
      LM_ERR("could not retrieve domain data\n");
      return -1;
   }

   LM_INFO("found carrier and domain, now adding failure route\n");
   return add_failure_route_to_tree(domain_data->failure_tree, scan_prefix, scan_prefix, host, reply_code,
         flags, mask, next_domain_id, comment);
}


static int fixup_rule_backup(struct route_flags * rf, struct route_rule * rr){
   struct route_rule_p_list * rl;
   if(!rr->status && rr->backup){
      if((rr->backup->rr = find_rule_by_hash(rf, rr->backup->hash_index)) == NULL){
         LM_ERR("didn't find backup route\n");
         return -1;
      }
   }
   rl = rr->backed_up;
   while(rl){
      if((rl->rr = find_rule_by_hash(rf, rl->hash_index)) == NULL){
         LM_ERR("didn't find backed up route\n");
         return -1;
      }
      rl = rl->next;
   }
   return 0;
}


/**
 * Does the work for rule_fixup recursively.
 * First, it tries to set a pointer the rules with an existing hash index
 * at the marching array index. Afterward, remaining rules are populated
 * with incrementing hash indices.
 *
 * @param node the prefix tree node to be fixed up
 *
 * @return 0 on success, -1 on failure
 */
static int rule_fixup_recursor(struct dtrie_node_t *node) {
   struct route_rule * rr;
   struct route_flags * rf;
   int i, p_dice, ret = 0;

   for (rf=(struct route_flags *)(node->data); rf!=NULL; rf=rf->next) {
      p_dice = 0;
      if (rf->rule_list) {
         rr = rf->rule_list;
         rf->rule_num = 0;
         while (rr) {
            rf->rule_num++;
            rf->dice_max += rr->prob * DICE_MAX;
            rr = rr->next;
         }
         rr = rf->rule_list;
         while (rr) {
            rr->dice_to = (rr->prob * DICE_MAX) + p_dice;
            p_dice = rr->dice_to;
            rr = rr->next;
         }
         
         if (rf->rule_num != rf->max_targets) {
            LM_ERR("number of rules(%i) differs from max_targets(%i), maybe your config is wrong?\n", rf->rule_num, rf->max_targets);
            return -1;
         }
         if(rf->rules) {
            shm_free(rf->rules);
            rf->rules = NULL;
         }
         if ((rf->rules = shm_malloc(sizeof(struct route_rule *) * rf->rule_num)) == NULL) {
            SHM_MEM_ERROR;
            return -1;
         }
         memset(rf->rules, 0, sizeof(struct route_rule *) * rf->rule_num);
         for (rr = rf->rule_list; rr; rr = rr->next) {
            if (rr->hash_index) {
               if (rr->hash_index > rf->rule_num) {
                  LM_ERR("too large hash index %i, max is %i\n", rr->hash_index, rf->rule_num);
                  shm_free(rf->rules);
                  return -1;
               }
               if (rf->rules[rr->hash_index - 1]) {
                  LM_ERR("duplicate hash index %i\n", rr->hash_index);
                  shm_free(rf->rules);
                  return -1;
               }
               rf->rules[rr->hash_index - 1] = rr;
               LM_INFO("rule with host %.*s hash has hashindex %i.\n", rr->host.len, rr->host.s, rr->hash_index);
            }
         }
         
         rr = rf->rule_list;
         i=0;
         while (rr && i < rf->rule_num) {
            if (!rr->hash_index) {
               if (rf->rules[i]) {
                  i++;
               } else {
                  rf->rules[i] = rr;
                  rr->hash_index = i + 1;
                  LM_INFO("hashless rule with host %.*s hash, hash_index %i\n", rr->host.len, rr->host.s, i+1);
                  rr = rr->next;
               }
            } else {
               rr = rr->next;
            }
         }
         if (rr) {
            LM_ERR("Could not populate rules: rr: %p\n", rr);
            return -1;
         }
         for(i=0; i<rf->rule_num; i++){
            ret += fixup_rule_backup(rf, rf->rules[i]);
         }
      }
   }

   for (i=0; i<cr_match_mode; i++) {
      if (node->child[i]) {
         ret += rule_fixup_recursor(node->child[i]);
      }
   }

   return ret;
}


/**
 * Fixes the route rules by creating an array for accessing
 * route rules by hash index directly
 *
 * @param rd route data to be fixed
 *
 * @return 0 on success, -1 on failure
 */
int rule_fixup(struct route_data_t * rd) {
   int i,j;
   for (i=0; i<rd->carrier_num; i++) {
      for (j=0; j<rd->carriers[i]->domain_num; j++) {
         if (rd->carriers[i]->domains[j] && rd->carriers[i]->domains[j]->tree) {
            LM_INFO("fixing tree %.*s\n", rd->carriers[i]->domains[j]->name->len, rd->carriers[i]->domains[j]->name->s);
            if (rule_fixup_recursor(rd->carriers[i]->domains[j]->tree) < 0) {
               return -1;
            }
         } else {
            LM_NOTICE("empty tree at [%i][%i]\n", i, j);
         }
      }
   }
   return 0;
}