contrib/unbound/edns-subnet/subnet-whitelist.c

   1 /*
   2  * edns-subnet/subnet-whitelist.c - Hosts we actively try to send subnet option
   3  * to.
   4  *
   5  * Copyright (c) 2013, NLnet Labs. All rights reserved.
   6  *
   7  * This software is open source.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * Redistributions of source code must retain the above copyright notice,
  14  * this list of conditions and the following disclaimer.
  15  *
  16  * Redistributions in binary form must reproduce the above copyright notice,
  17  * this list of conditions and the following disclaimer in the documentation
  18  * and/or other materials provided with the distribution.
  19  *
  20  * Neither the name of the NLNET LABS nor the names of its contributors may
  21  * be used to endorse or promote products derived from this software without
  22  * specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  26  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  27  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  28  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  30  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36 /**
  37  * \file
  38  *
  39  * Keep track of the white listed servers for subnet option. Based
  40  * on acl_list.c|h
  41  */
  42
  43 #include "config.h"
  44
  45 #ifdef CLIENT_SUBNET /* keeps splint happy */
  46 #include "edns-subnet/edns-subnet.h"
  47 #include "edns-subnet/subnet-whitelist.h"
  48 #include "util/regional.h"
  49 #include "util/log.h"
  50 #include "util/config_file.h"
  51 #include "util/net_help.h"
  52 #include "util/storage/dnstree.h"
  53 #include "sldns/str2wire.h"
  54 #include "util/data/dname.h"
  55
  56 struct ecs_whitelist*
  57 ecs_whitelist_create(void)
  58 {
  59         struct ecs_whitelist* whitelist =
  60                 (struct ecs_whitelist*)calloc(1,
  61                 sizeof(struct ecs_whitelist));
  62         if(!whitelist)
  63                 return NULL;
  64         whitelist->region = regional_create();
  65         if(!whitelist->region) {
  66                 ecs_whitelist_delete(whitelist);
  67                 return NULL;
  68         }
  69         return whitelist;
  70 }
  71
  72 void
  73 ecs_whitelist_delete(struct ecs_whitelist* whitelist)
  74 {
  75         if(!whitelist)
  76                 return;
  77         regional_destroy(whitelist->region);
  78         free(whitelist);
  79 }
  80
  81 /** insert new address into whitelist structure */
  82 static int
  83 upstream_insert(struct ecs_whitelist* whitelist,
  84         struct sockaddr_storage* addr, socklen_t addrlen, int net)
  85 {
  86         struct addr_tree_node* node = (struct addr_tree_node*)regional_alloc(
  87                 whitelist->region, sizeof(*node));
  88         if(!node)
  89                 return 0;
  90         if(!addr_tree_insert(&whitelist->upstream, node, addr, addrlen, net)) {
  91                 verbose(VERB_QUERY,
  92                         "duplicate send-client-subnet address ignored.");
  93         }
  94         return 1;
  95 }
  96
  97 /** apply edns-subnet string */
  98 static int
  99 upstream_str_cfg(struct ecs_whitelist* whitelist, const char* str)
 100 {
 101         struct sockaddr_storage addr;
 102         int net;
 103         socklen_t addrlen;
 104         verbose(VERB_ALGO, "send-client-subnet: %s", str);
 105         if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
 106                 log_err("cannot parse send-client-subnet netblock: %s", str);
 107                 return 0;
 108         }
 109         if(!upstream_insert(whitelist, &addr, addrlen, net)) {
 110                 log_err("out of memory");
 111                 return 0;
 112         }
 113         return 1;
 114 }
 115
 116 /** read client_subnet config */
 117 static int
 118 read_upstream(struct ecs_whitelist* whitelist, struct config_file* cfg)
 119 {
 120         struct config_strlist* p;
 121         for(p = cfg->client_subnet; p; p = p->next) {
 122                 log_assert(p->str);
 123                 if(!upstream_str_cfg(whitelist, p->str))
 124                         return 0;
 125         }
 126         return 1;
 127 }
 128
 129 /** read client_subnet_zone config */
 130 static int
 131 read_names(struct ecs_whitelist* whitelist, struct config_file* cfg)
 132 {
 133         /* parse names, report errors, insert into tree */
 134         struct config_strlist* p;
 135         struct name_tree_node* n;
 136         uint8_t* nm, *nmr;
 137         size_t nm_len;
 138         int nm_labs;
 139
 140         for(p = cfg->client_subnet_zone; p; p = p->next) {
 141                 log_assert(p->str);
 142                 nm = sldns_str2wire_dname(p->str, &nm_len);
 143                 if(!nm) {
 144                         log_err("cannot parse client-subnet-zone: %s", p->str);
 145                         return 0;
 146                 }
 147                 nm_labs = dname_count_size_labels(nm, &nm_len);
 148                 nmr = (uint8_t*)regional_alloc_init(whitelist->region, nm,
 149                         nm_len);
 150                 free(nm);
 151                 if(!nmr) {
 152                         log_err("out of memory");
 153                         return 0;
 154                 }
 155                 n = (struct name_tree_node*)regional_alloc(whitelist->region,
 156                         sizeof(*n));
 157                 if(!n) {
 158                         log_err("out of memory");
 159                         return 0;
 160                 }
 161                 if(!name_tree_insert(&whitelist->dname, n, nmr, nm_len, nm_labs,
 162                         LDNS_RR_CLASS_IN)) {
 163                         verbose(VERB_QUERY, "ignoring duplicate "
 164                                 "client-subnet-zone: %s", p->str);
 165                 }
 166         }
 167         return 1;
 168 }
 169
 170 int
 171 ecs_whitelist_apply_cfg(struct ecs_whitelist* whitelist,
 172         struct config_file* cfg)
 173 {
 174         regional_free_all(whitelist->region);
 175         addr_tree_init(&whitelist->upstream);
 176         name_tree_init(&whitelist->dname);
 177         if(!read_upstream(whitelist, cfg))
 178                 return 0;
 179         if(!read_names(whitelist, cfg))
 180                 return 0;
 181         addr_tree_init_parents(&whitelist->upstream);
 182         name_tree_init_parents(&whitelist->dname);
 183         return 1;
 184 }
 185
 186 int
 187 ecs_is_whitelisted(struct ecs_whitelist* whitelist,
 188         struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* qname,
 189         size_t qname_len, uint16_t qclass)
 190 {
 191         int labs;
 192         if(addr_tree_lookup(&whitelist->upstream, addr, addrlen))
 193                 return 1;
 194         /* Not in upstream whitelist, check dname whitelist. */
 195         labs = dname_count_labels(qname);
 196         return name_tree_lookup(&whitelist->dname, qname, qname_len, labs,
 197                 qclass) != NULL;
 198 }
 199
 200 size_t
 201 ecs_whitelist_get_mem(struct ecs_whitelist* whitelist)
 202 {
 203         if(!whitelist) return 0;
 204         return sizeof(*whitelist) + regional_get_mem(whitelist->region);
 205 }
 206
 207 #endif /* CLIENT_SUBNET */