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 */ 208