1 /* 2 * daemon/acl_list.h - client access control storage for the server. 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 helps the server keep out queries from outside sources, that 40 * should not be answered. 41 */ 42 #include "config.h" 43 #include "daemon/acl_list.h" 44 #include "util/regional.h" 45 #include "util/log.h" 46 #include "util/config_file.h" 47 #include "util/net_help.h" 48 #include "services/localzone.h" 49 #include "sldns/str2wire.h" 50 51 struct acl_list* 52 acl_list_create(void) 53 { 54 struct acl_list* acl = (struct acl_list*)calloc(1, 55 sizeof(struct acl_list)); 56 if(!acl) 57 return NULL; 58 acl->region = regional_create(); 59 if(!acl->region) { 60 acl_list_delete(acl); 61 return NULL; 62 } 63 return acl; 64 } 65 66 void 67 acl_list_delete(struct acl_list* acl) 68 { 69 if(!acl) 70 return; 71 regional_destroy(acl->region); 72 free(acl); 73 } 74 75 /** insert new address into acl_list structure */ 76 static struct acl_addr* 77 acl_list_insert(struct acl_list* acl, struct sockaddr_storage* addr, 78 socklen_t addrlen, int net, enum acl_access control, 79 int complain_duplicates) 80 { 81 struct acl_addr* node = regional_alloc_zero(acl->region, 82 sizeof(struct acl_addr)); 83 if(!node) 84 return NULL; 85 node->control = control; 86 if(!addr_tree_insert(&acl->tree, &node->node, addr, addrlen, net)) { 87 if(complain_duplicates) 88 verbose(VERB_QUERY, "duplicate acl address ignored."); 89 } 90 return node; 91 } 92 93 /** apply acl_list string */ 94 static int 95 acl_list_str_cfg(struct acl_list* acl, const char* str, const char* s2, 96 int complain_duplicates) 97 { 98 struct sockaddr_storage addr; 99 int net; 100 socklen_t addrlen; 101 enum acl_access control; 102 if(strcmp(s2, "allow") == 0) 103 control = acl_allow; 104 else if(strcmp(s2, "deny") == 0) 105 control = acl_deny; 106 else if(strcmp(s2, "refuse") == 0) 107 control = acl_refuse; 108 else if(strcmp(s2, "deny_non_local") == 0) 109 control = acl_deny_non_local; 110 else if(strcmp(s2, "refuse_non_local") == 0) 111 control = acl_refuse_non_local; 112 else if(strcmp(s2, "allow_snoop") == 0) 113 control = acl_allow_snoop; 114 else if(strcmp(s2, "allow_setrd") == 0) 115 control = acl_allow_setrd; 116 else { 117 log_err("access control type %s unknown", str); 118 return 0; 119 } 120 if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) { 121 log_err("cannot parse access control: %s %s", str, s2); 122 return 0; 123 } 124 if(!acl_list_insert(acl, &addr, addrlen, net, control, 125 complain_duplicates)) { 126 log_err("out of memory"); 127 return 0; 128 } 129 return 1; 130 } 131 132 /** find or create node (NULL on parse or error) */ 133 static struct acl_addr* 134 acl_find_or_create(struct acl_list* acl, const char* str) 135 { 136 struct acl_addr* node; 137 struct sockaddr_storage addr; 138 int net; 139 socklen_t addrlen; 140 if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) { 141 log_err("cannot parse netblock: %s", str); 142 return NULL; 143 } 144 /* find or create node */ 145 if(!(node=(struct acl_addr*)addr_tree_find(&acl->tree, &addr, 146 addrlen, net))) { 147 /* create node, type 'allow' since otherwise tags are 148 * pointless, can override with specific access-control: cfg */ 149 if(!(node=(struct acl_addr*)acl_list_insert(acl, &addr, 150 addrlen, net, acl_allow, 1))) { 151 log_err("out of memory"); 152 return NULL; 153 } 154 } 155 return node; 156 } 157 158 /** apply acl_tag string */ 159 static int 160 acl_list_tags_cfg(struct acl_list* acl, const char* str, uint8_t* bitmap, 161 size_t bitmaplen) 162 { 163 struct acl_addr* node; 164 if(!(node=acl_find_or_create(acl, str))) 165 return 0; 166 node->taglen = bitmaplen; 167 node->taglist = regional_alloc_init(acl->region, bitmap, bitmaplen); 168 if(!node->taglist) { 169 log_err("out of memory"); 170 return 0; 171 } 172 return 1; 173 } 174 175 /** apply acl_view string */ 176 static int 177 acl_list_view_cfg(struct acl_list* acl, const char* str, const char* str2, 178 struct views* vs) 179 { 180 struct acl_addr* node; 181 if(!(node=acl_find_or_create(acl, str))) 182 return 0; 183 node->view = views_find_view(vs, str2, 0 /* get read lock*/); 184 if(!node->view) { 185 log_err("no view with name: %s", str2); 186 return 0; 187 } 188 lock_rw_unlock(&node->view->lock); 189 return 1; 190 } 191 192 /** apply acl_tag_action string */ 193 static int 194 acl_list_tag_action_cfg(struct acl_list* acl, struct config_file* cfg, 195 const char* str, const char* tag, const char* action) 196 { 197 struct acl_addr* node; 198 int tagid; 199 enum localzone_type t; 200 if(!(node=acl_find_or_create(acl, str))) 201 return 0; 202 /* allocate array if not yet */ 203 if(!node->tag_actions) { 204 node->tag_actions = (uint8_t*)regional_alloc_zero(acl->region, 205 sizeof(*node->tag_actions)*cfg->num_tags); 206 if(!node->tag_actions) { 207 log_err("out of memory"); 208 return 0; 209 } 210 node->tag_actions_size = (size_t)cfg->num_tags; 211 } 212 /* parse tag */ 213 if((tagid=find_tag_id(cfg, tag)) == -1) { 214 log_err("cannot parse tag (define-tag it): %s %s", str, tag); 215 return 0; 216 } 217 if((size_t)tagid >= node->tag_actions_size) { 218 log_err("tagid too large for array %s %s", str, tag); 219 return 0; 220 } 221 if(!local_zone_str2type(action, &t)) { 222 log_err("cannot parse access control action type: %s %s %s", 223 str, tag, action); 224 return 0; 225 } 226 node->tag_actions[tagid] = (uint8_t)t; 227 return 1; 228 } 229 230 /** check wire data parse */ 231 static int 232 check_data(const char* data, const struct config_strlist* head) 233 { 234 char buf[65536]; 235 uint8_t rr[LDNS_RR_BUF_SIZE]; 236 size_t len = sizeof(rr); 237 int res; 238 /* '.' is sufficient for validation, and it makes the call to 239 * sldns_wirerr_get_type() simpler below. */ 240 snprintf(buf, sizeof(buf), "%s %s", ".", data); 241 res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, NULL, 0, 242 NULL, 0); 243 244 /* Reject it if we would end up having CNAME and other data (including 245 * another CNAME) for the same tag. */ 246 if(res == 0 && head) { 247 const char* err_data = NULL; 248 249 if(sldns_wirerr_get_type(rr, len, 1) == LDNS_RR_TYPE_CNAME) { 250 /* adding CNAME while other data already exists. */ 251 err_data = data; 252 } else { 253 snprintf(buf, sizeof(buf), "%s %s", ".", head->str); 254 len = sizeof(rr); 255 res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, 256 NULL, 0, NULL, 0); 257 if(res != 0) { 258 /* This should be impossible here as head->str 259 * has been validated, but we check it just in 260 * case. */ 261 return 0; 262 } 263 if(sldns_wirerr_get_type(rr, len, 1) == 264 LDNS_RR_TYPE_CNAME) /* already have CNAME */ 265 err_data = head->str; 266 } 267 if(err_data) { 268 log_err("redirect tag data '%s' must not coexist with " 269 "other data.", err_data); 270 return 0; 271 } 272 } 273 if(res == 0) 274 return 1; 275 log_err("rr data [char %d] parse error %s", 276 (int)LDNS_WIREPARSE_OFFSET(res)-2, 277 sldns_get_errorstr_parse(res)); 278 return 0; 279 } 280 281 /** apply acl_tag_data string */ 282 static int 283 acl_list_tag_data_cfg(struct acl_list* acl, struct config_file* cfg, 284 const char* str, const char* tag, const char* data) 285 { 286 struct acl_addr* node; 287 int tagid; 288 char* dupdata; 289 if(!(node=acl_find_or_create(acl, str))) 290 return 0; 291 /* allocate array if not yet */ 292 if(!node->tag_datas) { 293 node->tag_datas = (struct config_strlist**)regional_alloc_zero( 294 acl->region, sizeof(*node->tag_datas)*cfg->num_tags); 295 if(!node->tag_datas) { 296 log_err("out of memory"); 297 return 0; 298 } 299 node->tag_datas_size = (size_t)cfg->num_tags; 300 } 301 /* parse tag */ 302 if((tagid=find_tag_id(cfg, tag)) == -1) { 303 log_err("cannot parse tag (define-tag it): %s %s", str, tag); 304 return 0; 305 } 306 if((size_t)tagid >= node->tag_datas_size) { 307 log_err("tagid too large for array %s %s", str, tag); 308 return 0; 309 } 310 311 /* check data? */ 312 if(!check_data(data, node->tag_datas[tagid])) { 313 log_err("cannot parse access-control-tag data: %s %s '%s'", 314 str, tag, data); 315 return 0; 316 } 317 318 dupdata = regional_strdup(acl->region, data); 319 if(!dupdata) { 320 log_err("out of memory"); 321 return 0; 322 } 323 if(!cfg_region_strlist_insert(acl->region, 324 &(node->tag_datas[tagid]), dupdata)) { 325 log_err("out of memory"); 326 return 0; 327 } 328 return 1; 329 } 330 331 /** read acl_list config */ 332 static int 333 read_acl_list(struct acl_list* acl, struct config_file* cfg) 334 { 335 struct config_str2list* p; 336 for(p = cfg->acls; p; p = p->next) { 337 log_assert(p->str && p->str2); 338 if(!acl_list_str_cfg(acl, p->str, p->str2, 1)) 339 return 0; 340 } 341 return 1; 342 } 343 344 /** read acl tags config */ 345 static int 346 read_acl_tags(struct acl_list* acl, struct config_file* cfg) 347 { 348 struct config_strbytelist* np, *p = cfg->acl_tags; 349 cfg->acl_tags = NULL; 350 while(p) { 351 log_assert(p->str && p->str2); 352 if(!acl_list_tags_cfg(acl, p->str, p->str2, p->str2len)) { 353 config_del_strbytelist(p); 354 return 0; 355 } 356 /* free the items as we go to free up memory */ 357 np = p->next; 358 free(p->str); 359 free(p->str2); 360 free(p); 361 p = np; 362 } 363 return 1; 364 } 365 366 /** read acl view config */ 367 static int 368 read_acl_view(struct acl_list* acl, struct config_file* cfg, struct views* v) 369 { 370 struct config_str2list* np, *p = cfg->acl_view; 371 cfg->acl_view = NULL; 372 while(p) { 373 log_assert(p->str && p->str2); 374 if(!acl_list_view_cfg(acl, p->str, p->str2, v)) { 375 return 0; 376 } 377 /* free the items as we go to free up memory */ 378 np = p->next; 379 free(p->str); 380 free(p->str2); 381 free(p); 382 p = np; 383 } 384 return 1; 385 } 386 387 /** read acl tag actions config */ 388 static int 389 read_acl_tag_actions(struct acl_list* acl, struct config_file* cfg) 390 { 391 struct config_str3list* p, *np; 392 p = cfg->acl_tag_actions; 393 cfg->acl_tag_actions = NULL; 394 while(p) { 395 log_assert(p->str && p->str2 && p->str3); 396 if(!acl_list_tag_action_cfg(acl, cfg, p->str, p->str2, 397 p->str3)) { 398 config_deltrplstrlist(p); 399 return 0; 400 } 401 /* free the items as we go to free up memory */ 402 np = p->next; 403 free(p->str); 404 free(p->str2); 405 free(p->str3); 406 free(p); 407 p = np; 408 } 409 return 1; 410 } 411 412 /** read acl tag datas config */ 413 static int 414 read_acl_tag_datas(struct acl_list* acl, struct config_file* cfg) 415 { 416 struct config_str3list* p, *np; 417 p = cfg->acl_tag_datas; 418 cfg->acl_tag_datas = NULL; 419 while(p) { 420 log_assert(p->str && p->str2 && p->str3); 421 if(!acl_list_tag_data_cfg(acl, cfg, p->str, p->str2, p->str3)) { 422 config_deltrplstrlist(p); 423 return 0; 424 } 425 /* free the items as we go to free up memory */ 426 np = p->next; 427 free(p->str); 428 free(p->str2); 429 free(p->str3); 430 free(p); 431 p = np; 432 } 433 return 1; 434 } 435 436 int 437 acl_list_apply_cfg(struct acl_list* acl, struct config_file* cfg, 438 struct views* v) 439 { 440 regional_free_all(acl->region); 441 addr_tree_init(&acl->tree); 442 if(!read_acl_list(acl, cfg)) 443 return 0; 444 if(!read_acl_view(acl, cfg, v)) 445 return 0; 446 if(!read_acl_tags(acl, cfg)) 447 return 0; 448 if(!read_acl_tag_actions(acl, cfg)) 449 return 0; 450 if(!read_acl_tag_datas(acl, cfg)) 451 return 0; 452 /* insert defaults, with '0' to ignore them if they are duplicates */ 453 if(!acl_list_str_cfg(acl, "0.0.0.0/0", "refuse", 0)) 454 return 0; 455 if(!acl_list_str_cfg(acl, "127.0.0.0/8", "allow", 0)) 456 return 0; 457 if(cfg->do_ip6) { 458 if(!acl_list_str_cfg(acl, "::0/0", "refuse", 0)) 459 return 0; 460 if(!acl_list_str_cfg(acl, "::1", "allow", 0)) 461 return 0; 462 if(!acl_list_str_cfg(acl, "::ffff:127.0.0.1", "allow", 0)) 463 return 0; 464 } 465 addr_tree_init_parents(&acl->tree); 466 return 1; 467 } 468 469 enum acl_access 470 acl_get_control(struct acl_addr* acl) 471 { 472 if(acl) return acl->control; 473 return acl_deny; 474 } 475 476 struct acl_addr* 477 acl_addr_lookup(struct acl_list* acl, struct sockaddr_storage* addr, 478 socklen_t addrlen) 479 { 480 return (struct acl_addr*)addr_tree_lookup(&acl->tree, 481 addr, addrlen); 482 } 483 484 size_t 485 acl_list_get_mem(struct acl_list* acl) 486 { 487 if(!acl) return 0; 488 return sizeof(*acl) + regional_get_mem(acl->region); 489 } 490 491 const char* acl_access_to_str(enum acl_access acl) 492 { 493 switch(acl) { 494 case acl_deny: return "deny"; 495 case acl_refuse: return "refuse"; 496 case acl_deny_non_local: return "deny_non_local"; 497 case acl_refuse_non_local: return "refuse_non_local"; 498 case acl_allow: return "allow"; 499 case acl_allow_snoop: return "allow_snoop"; 500 case acl_allow_setrd: return "allow_setrd"; 501 default: break; 502 } 503 return "unknown"; 504 } 505 506 void 507 log_acl_action(const char* action, struct sockaddr_storage* addr, 508 socklen_t addrlen, enum acl_access acl, struct acl_addr* acladdr) 509 { 510 char a[128], n[128]; 511 uint16_t port; 512 addr_to_str(addr, addrlen, a, sizeof(a)); 513 port = ntohs(((struct sockaddr_in*)addr)->sin_port); 514 if(acladdr) { 515 addr_to_str(&acladdr->node.addr, acladdr->node.addrlen, 516 n, sizeof(n)); 517 verbose(VERB_ALGO, "%s query from %s port %d because of " 518 "%s/%d %s", action, a, (int)port, n, acladdr->node.net, 519 acl_access_to_str(acl)); 520 } else { 521 verbose(VERB_ALGO, "%s query from %s port %d", action, a, 522 (int)port); 523 } 524 } 525