1 /* 2 * libunbound/context.c - validating context for unbound internal use 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 the validator context structure. 40 */ 41 #include "config.h" 42 #include "libunbound/context.h" 43 #include "util/module.h" 44 #include "util/config_file.h" 45 #include "util/net_help.h" 46 #include "services/modstack.h" 47 #include "services/localzone.h" 48 #include "services/cache/rrset.h" 49 #include "services/cache/infra.h" 50 #include "services/authzone.h" 51 #include "util/data/msgreply.h" 52 #include "util/storage/slabhash.h" 53 #include "sldns/sbuffer.h" 54 55 int 56 context_finalize(struct ub_ctx* ctx) 57 { 58 struct config_file* cfg = ctx->env->cfg; 59 verbosity = cfg->verbosity; 60 if(ctx->logfile_override) 61 log_file(ctx->log_out); 62 else log_init(cfg->logfile, cfg->use_syslog, NULL); 63 config_apply(cfg); 64 if(!modstack_setup(&ctx->mods, cfg->module_conf, ctx->env)) 65 return UB_INITFAIL; 66 log_edns_known_options(VERB_ALGO, ctx->env); 67 ctx->local_zones = local_zones_create(); 68 if(!ctx->local_zones) 69 return UB_NOMEM; 70 if(!local_zones_apply_cfg(ctx->local_zones, cfg)) 71 return UB_INITFAIL; 72 if(!auth_zones_apply_cfg(ctx->env->auth_zones, cfg, 1)) 73 return UB_INITFAIL; 74 if(!ctx->env->msg_cache || 75 cfg->msg_cache_size != slabhash_get_size(ctx->env->msg_cache) || 76 cfg->msg_cache_slabs != ctx->env->msg_cache->size) { 77 slabhash_delete(ctx->env->msg_cache); 78 ctx->env->msg_cache = slabhash_create(cfg->msg_cache_slabs, 79 HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size, 80 msgreply_sizefunc, query_info_compare, 81 query_entry_delete, reply_info_delete, NULL); 82 if(!ctx->env->msg_cache) 83 return UB_NOMEM; 84 } 85 ctx->env->rrset_cache = rrset_cache_adjust(ctx->env->rrset_cache, 86 ctx->env->cfg, ctx->env->alloc); 87 if(!ctx->env->rrset_cache) 88 return UB_NOMEM; 89 ctx->env->infra_cache = infra_adjust(ctx->env->infra_cache, cfg); 90 if(!ctx->env->infra_cache) 91 return UB_NOMEM; 92 ctx->finalized = 1; 93 return UB_NOERROR; 94 } 95 96 int context_query_cmp(const void* a, const void* b) 97 { 98 if( *(int*)a < *(int*)b ) 99 return -1; 100 if( *(int*)a > *(int*)b ) 101 return 1; 102 return 0; 103 } 104 105 void 106 context_query_delete(struct ctx_query* q) 107 { 108 if(!q) return; 109 ub_resolve_free(q->res); 110 free(q->msg); 111 free(q); 112 } 113 114 /** How many times to try to find an unused query-id-number for async */ 115 #define NUM_ID_TRIES 100000 116 /** find next useful id number of 0 on error */ 117 static int 118 find_id(struct ub_ctx* ctx, int* id) 119 { 120 size_t tries = 0; 121 ctx->next_querynum++; 122 while(rbtree_search(&ctx->queries, &ctx->next_querynum)) { 123 ctx->next_querynum++; /* numerical wraparound is fine */ 124 if(tries++ > NUM_ID_TRIES) 125 return 0; 126 } 127 *id = ctx->next_querynum; 128 return 1; 129 } 130 131 struct ctx_query* 132 context_new(struct ub_ctx* ctx, const char* name, int rrtype, int rrclass, 133 ub_callback_type cb, void* cbarg) 134 { 135 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q)); 136 if(!q) return NULL; 137 lock_basic_lock(&ctx->cfglock); 138 if(!find_id(ctx, &q->querynum)) { 139 lock_basic_unlock(&ctx->cfglock); 140 free(q); 141 return NULL; 142 } 143 lock_basic_unlock(&ctx->cfglock); 144 q->node.key = &q->querynum; 145 q->async = (cb != NULL); 146 q->cb = cb; 147 q->cb_arg = cbarg; 148 q->res = (struct ub_result*)calloc(1, sizeof(*q->res)); 149 if(!q->res) { 150 free(q); 151 return NULL; 152 } 153 q->res->qname = strdup(name); 154 if(!q->res->qname) { 155 free(q->res); 156 free(q); 157 return NULL; 158 } 159 q->res->qtype = rrtype; 160 q->res->qclass = rrclass; 161 162 /* add to query list */ 163 lock_basic_lock(&ctx->cfglock); 164 if(q->async) 165 ctx->num_async ++; 166 (void)rbtree_insert(&ctx->queries, &q->node); 167 lock_basic_unlock(&ctx->cfglock); 168 return q; 169 } 170 171 struct alloc_cache* 172 context_obtain_alloc(struct ub_ctx* ctx, int locking) 173 { 174 struct alloc_cache* a; 175 int tnum = 0; 176 if(locking) { 177 lock_basic_lock(&ctx->cfglock); 178 } 179 a = ctx->alloc_list; 180 if(a) 181 ctx->alloc_list = a->super; /* snip off list */ 182 else tnum = ctx->thr_next_num++; 183 if(locking) { 184 lock_basic_unlock(&ctx->cfglock); 185 } 186 if(a) { 187 a->super = &ctx->superalloc; 188 return a; 189 } 190 a = (struct alloc_cache*)calloc(1, sizeof(*a)); 191 if(!a) 192 return NULL; 193 alloc_init(a, &ctx->superalloc, tnum); 194 return a; 195 } 196 197 void 198 context_release_alloc(struct ub_ctx* ctx, struct alloc_cache* alloc, 199 int locking) 200 { 201 if(!ctx || !alloc) 202 return; 203 if(locking) { 204 lock_basic_lock(&ctx->cfglock); 205 } 206 alloc->super = ctx->alloc_list; 207 ctx->alloc_list = alloc; 208 if(locking) { 209 lock_basic_unlock(&ctx->cfglock); 210 } 211 } 212 213 uint8_t* 214 context_serialize_new_query(struct ctx_query* q, uint32_t* len) 215 { 216 /* format for new query is 217 * o uint32 cmd 218 * o uint32 id 219 * o uint32 type 220 * o uint32 class 221 * o rest queryname (string) 222 */ 223 uint8_t* p; 224 size_t slen = strlen(q->res->qname) + 1/*end of string*/; 225 *len = sizeof(uint32_t)*4 + slen; 226 p = (uint8_t*)malloc(*len); 227 if(!p) return NULL; 228 sldns_write_uint32(p, UB_LIBCMD_NEWQUERY); 229 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 230 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)q->res->qtype); 231 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->res->qclass); 232 memmove(p+4*sizeof(uint32_t), q->res->qname, slen); 233 return p; 234 } 235 236 struct ctx_query* 237 context_deserialize_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len) 238 { 239 struct ctx_query* q = (struct ctx_query*)calloc(1, sizeof(*q)); 240 if(!q) return NULL; 241 if(len < 4*sizeof(uint32_t)+1) { 242 free(q); 243 return NULL; 244 } 245 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY); 246 q->querynum = (int)sldns_read_uint32(p+sizeof(uint32_t)); 247 q->node.key = &q->querynum; 248 q->async = 1; 249 q->res = (struct ub_result*)calloc(1, sizeof(*q->res)); 250 if(!q->res) { 251 free(q); 252 return NULL; 253 } 254 q->res->qtype = (int)sldns_read_uint32(p+2*sizeof(uint32_t)); 255 q->res->qclass = (int)sldns_read_uint32(p+3*sizeof(uint32_t)); 256 q->res->qname = strdup((char*)(p+4*sizeof(uint32_t))); 257 if(!q->res->qname) { 258 free(q->res); 259 free(q); 260 return NULL; 261 } 262 263 /** add to query list */ 264 ctx->num_async++; 265 (void)rbtree_insert(&ctx->queries, &q->node); 266 return q; 267 } 268 269 struct ctx_query* 270 context_lookup_new_query(struct ub_ctx* ctx, uint8_t* p, uint32_t len) 271 { 272 struct ctx_query* q; 273 int querynum; 274 if(len < 4*sizeof(uint32_t)+1) { 275 return NULL; 276 } 277 log_assert( sldns_read_uint32(p) == UB_LIBCMD_NEWQUERY); 278 querynum = (int)sldns_read_uint32(p+sizeof(uint32_t)); 279 q = (struct ctx_query*)rbtree_search(&ctx->queries, &querynum); 280 if(!q) { 281 return NULL; 282 } 283 log_assert(q->async); 284 return q; 285 } 286 287 uint8_t* 288 context_serialize_answer(struct ctx_query* q, int err, sldns_buffer* pkt, 289 uint32_t* len) 290 { 291 /* answer format 292 * o uint32 cmd 293 * o uint32 id 294 * o uint32 error_code 295 * o uint32 msg_security 296 * o uint32 length of why_bogus string (+1 for eos); 0 absent. 297 * o why_bogus_string 298 * o the remainder is the answer msg from resolver lookup. 299 * remainder can be length 0. 300 */ 301 size_t pkt_len = pkt?sldns_buffer_remaining(pkt):0; 302 size_t wlen = (pkt&&q->res->why_bogus)?strlen(q->res->why_bogus)+1:0; 303 uint8_t* p; 304 *len = sizeof(uint32_t)*5 + pkt_len + wlen; 305 p = (uint8_t*)malloc(*len); 306 if(!p) return NULL; 307 sldns_write_uint32(p, UB_LIBCMD_ANSWER); 308 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 309 sldns_write_uint32(p+2*sizeof(uint32_t), (uint32_t)err); 310 sldns_write_uint32(p+3*sizeof(uint32_t), (uint32_t)q->msg_security); 311 sldns_write_uint32(p+4*sizeof(uint32_t), (uint32_t)wlen); 312 if(wlen > 0) 313 memmove(p+5*sizeof(uint32_t), q->res->why_bogus, wlen); 314 if(pkt_len > 0) 315 memmove(p+5*sizeof(uint32_t)+wlen, 316 sldns_buffer_begin(pkt), pkt_len); 317 return p; 318 } 319 320 struct ctx_query* 321 context_deserialize_answer(struct ub_ctx* ctx, 322 uint8_t* p, uint32_t len, int* err) 323 { 324 struct ctx_query* q = NULL ; 325 int id; 326 size_t wlen; 327 if(len < 5*sizeof(uint32_t)) return NULL; 328 log_assert( sldns_read_uint32(p) == UB_LIBCMD_ANSWER); 329 id = (int)sldns_read_uint32(p+sizeof(uint32_t)); 330 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id); 331 if(!q) return NULL; 332 *err = (int)sldns_read_uint32(p+2*sizeof(uint32_t)); 333 q->msg_security = sldns_read_uint32(p+3*sizeof(uint32_t)); 334 wlen = (size_t)sldns_read_uint32(p+4*sizeof(uint32_t)); 335 if(len > 5*sizeof(uint32_t) && wlen > 0) { 336 if(len >= 5*sizeof(uint32_t)+wlen) 337 q->res->why_bogus = (char*)memdup( 338 p+5*sizeof(uint32_t), wlen); 339 if(!q->res->why_bogus) { 340 /* pass malloc failure to the user callback */ 341 q->msg_len = 0; 342 *err = UB_NOMEM; 343 return q; 344 } 345 q->res->why_bogus[wlen-1] = 0; /* zero terminated for sure */ 346 } 347 if(len > 5*sizeof(uint32_t)+wlen) { 348 q->msg_len = len - 5*sizeof(uint32_t) - wlen; 349 q->msg = (uint8_t*)memdup(p+5*sizeof(uint32_t)+wlen, 350 q->msg_len); 351 if(!q->msg) { 352 /* pass malloc failure to the user callback */ 353 q->msg_len = 0; 354 *err = UB_NOMEM; 355 return q; 356 } 357 } 358 return q; 359 } 360 361 uint8_t* 362 context_serialize_cancel(struct ctx_query* q, uint32_t* len) 363 { 364 /* format of cancel: 365 * o uint32 cmd 366 * o uint32 async-id */ 367 uint8_t* p = (uint8_t*)reallocarray(NULL, sizeof(uint32_t), 2); 368 if(!p) return NULL; 369 *len = 2*sizeof(uint32_t); 370 sldns_write_uint32(p, UB_LIBCMD_CANCEL); 371 sldns_write_uint32(p+sizeof(uint32_t), (uint32_t)q->querynum); 372 return p; 373 } 374 375 struct ctx_query* context_deserialize_cancel(struct ub_ctx* ctx, 376 uint8_t* p, uint32_t len) 377 { 378 struct ctx_query* q; 379 int id; 380 if(len != 2*sizeof(uint32_t)) return NULL; 381 log_assert( sldns_read_uint32(p) == UB_LIBCMD_CANCEL); 382 id = (int)sldns_read_uint32(p+sizeof(uint32_t)); 383 q = (struct ctx_query*)rbtree_search(&ctx->queries, &id); 384 return q; 385 } 386 387 uint8_t* 388 context_serialize_quit(uint32_t* len) 389 { 390 uint8_t* p = (uint8_t*)malloc(sizeof(uint32_t)); 391 if(!p) 392 return NULL; 393 *len = sizeof(uint32_t); 394 sldns_write_uint32(p, UB_LIBCMD_QUIT); 395 return p; 396 } 397 398 enum ub_ctx_cmd context_serial_getcmd(uint8_t* p, uint32_t len) 399 { 400 uint32_t v; 401 if((size_t)len < sizeof(v)) 402 return UB_LIBCMD_QUIT; 403 v = sldns_read_uint32(p); 404 return v; 405 } 406