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