unbound/iterator/iter_donotq.c

   1 /*
   2  * iterator/iter_donotq.c - iterative resolver donotqueryaddresses storage.
   3  *
   4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
   5  *
   6  * This software is open source.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * Redistributions of source code must retain the above copyright notice,
  13  * this list of conditions and the following disclaimer.
  14  *
  15  * Redistributions in binary form must reproduce the above copyright notice,
  16  * this list of conditions and the following disclaimer in the documentation
  17  * and/or other materials provided with the distribution.
  18  *
  19  * Neither the name of the NLNET LABS nor the names of its contributors may
  20  * be used to endorse or promote products derived from this software without
  21  * specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  */
  35
  36 /**
  37  * \file
  38  *
  39  * This file contains functions to assist the iterator module.
  40  * The donotqueryaddresses are stored and looked up. These addresses
  41  * (like 127.0.0.1) must not be used to send queries to, and can be
  42  * discarded immediately from the server selection.
  43  */
  44 #include "config.h"
  45 #include "iterator/iter_donotq.h"
  46 #include "util/regional.h"
  47 #include "util/log.h"
  48 #include "util/config_file.h"
  49 #include "util/net_help.h"
  50
  51 struct iter_donotq*
  52 donotq_create(void)
  53 {
  54         struct iter_donotq* dq = (struct iter_donotq*)calloc(1,
  55                 sizeof(struct iter_donotq));
  56         if(!dq)
  57                 return NULL;
  58         dq->region = regional_create();
  59         if(!dq->region) {
  60                 donotq_delete(dq);
  61                 return NULL;
  62         }
  63         return dq;
  64 }
  65
  66 void
  67 donotq_delete(struct iter_donotq* dq)
  68 {
  69         if(!dq)
  70                 return;
  71         regional_destroy(dq->region);
  72         free(dq);
  73 }
  74
  75 /** insert new address into donotq structure */
  76 static int
  77 donotq_insert(struct iter_donotq* dq, struct sockaddr_storage* addr,
  78         socklen_t addrlen, int net)
  79 {
  80         struct addr_tree_node* node = (struct addr_tree_node*)regional_alloc(
  81                 dq->region, sizeof(*node));
  82         if(!node)
  83                 return 0;
  84         if(!addr_tree_insert(&dq->tree, node, addr, addrlen, net)) {
  85                 verbose(VERB_QUERY, "duplicate donotquery address ignored.");
  86         }
  87         return 1;
  88 }
  89
  90 /** apply donotq string */
  91 static int
  92 donotq_str_cfg(struct iter_donotq* dq, const char* str)
  93 {
  94         struct sockaddr_storage addr;
  95         int net;
  96         socklen_t addrlen;
  97         verbose(VERB_ALGO, "donotq: %s", str);
  98         if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
  99                 log_err("cannot parse donotquery netblock: %s", str);
 100                 return 0;
 101         }
 102         if(!donotq_insert(dq, &addr, addrlen, net)) {
 103                 log_err("out of memory");
 104                 return 0;
 105         }
 106         return 1;
 107 }
 108
 109 /** read donotq config */
 110 static int
 111 read_donotq(struct iter_donotq* dq, struct config_file* cfg)
 112 {
 113         struct config_strlist* p;
 114         for(p = cfg->donotqueryaddrs; p; p = p->next) {
 115                 log_assert(p->str);
 116                 if(!donotq_str_cfg(dq, p->str))
 117                         return 0;
 118         }
 119         return 1;
 120 }
 121
 122 int
 123 donotq_apply_cfg(struct iter_donotq* dq, struct config_file* cfg)
 124 {
 125         regional_free_all(dq->region);
 126         addr_tree_init(&dq->tree);
 127         if(!read_donotq(dq, cfg))
 128                 return 0;
 129         if(cfg->donotquery_localhost) {
 130                 if(!donotq_str_cfg(dq, "127.0.0.0/8"))
 131                         return 0;
 132                 if(cfg->do_ip6) {
 133                         if(!donotq_str_cfg(dq, "::1"))
 134                                 return 0;
 135                 }
 136         }
 137         addr_tree_init_parents(&dq->tree);
 138         return 1;
 139 }
 140
 141 int
 142 donotq_lookup(struct iter_donotq* donotq, struct sockaddr_storage* addr,
 143         socklen_t addrlen)
 144 {
 145         return addr_tree_lookup(&donotq->tree, addr, addrlen) != NULL;
 146 }
 147
 148 size_t
 149 donotq_get_mem(struct iter_donotq* donotq)
 150 {
 151         if(!donotq) return 0;
 152         return sizeof(*donotq) + regional_get_mem(donotq->region);
 153 }