contrib/unbound/iterator/iter_hints.c

   1 /*
   2  * iterator/iter_hints.c - iterative resolver module stub and root hints.
   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 functions to assist the iterator module.
  40  * Keep track of stub and root hints, and read those from config.
  41  */
  42 #include "config.h"
  43 #include "iterator/iter_hints.h"
  44 #include "iterator/iter_delegpt.h"
  45 #include "util/log.h"
  46 #include "util/config_file.h"
  47 #include "util/net_help.h"
  48 #include "util/data/dname.h"
  49 #include "sldns/rrdef.h"
  50 #include "sldns/str2wire.h"
  51 #include "sldns/wire2str.h"
  52
  53 struct iter_hints*
  54 hints_create(void)
  55 {
  56         struct iter_hints* hints = (struct iter_hints*)calloc(1,
  57                 sizeof(struct iter_hints));
  58         if(!hints)
  59                 return NULL;
  60         return hints;
  61 }
  62
  63 static void hints_stub_free(struct iter_hints_stub* s)
  64 {
  65         if(!s) return;
  66         delegpt_free_mlc(s->dp);
  67         free(s);
  68 }
  69
  70 static void delhintnode(rbnode_t* n, void* ATTR_UNUSED(arg))
  71 {
  72         struct iter_hints_stub* node = (struct iter_hints_stub*)n;
  73         hints_stub_free(node);
  74 }
  75
  76 static void hints_del_tree(struct iter_hints* hints)
  77 {
  78         traverse_postorder(&hints->tree, &delhintnode, NULL);
  79 }
  80
  81 void
  82 hints_delete(struct iter_hints* hints)
  83 {
  84         if(!hints)
  85                 return;
  86         hints_del_tree(hints);
  87         free(hints);
  88 }
  89
  90 /** add hint to delegation hints */
  91 static int
  92 ah(struct delegpt* dp, const char* sv, const char* ip)
  93 {
  94         struct sockaddr_storage addr;
  95         socklen_t addrlen;
  96         size_t dname_len;
  97         uint8_t* dname = sldns_str2wire_dname(sv, &dname_len);
  98         if(!dname) {
  99                 log_err("could not parse %s", sv);
 100                 return 0;
 101         }
 102         if(!delegpt_add_ns_mlc(dp, dname, 0) ||
 103            !extstrtoaddr(ip, &addr, &addrlen) ||
 104            !delegpt_add_target_mlc(dp, dname, dname_len,
 105                 &addr, addrlen, 0, 0)) {
 106                 free(dname);
 107                 return 0;
 108         }
 109         free(dname);
 110         return 1;
 111 }
 112
 113 /** obtain compiletime provided root hints */
 114 static struct delegpt*
 115 compile_time_root_prime(int do_ip4, int do_ip6)
 116 {
 117         /* from:
 118          ;       This file is made available by InterNIC
 119          ;       under anonymous FTP as
 120          ;           file                /domain/named.cache
 121          ;           on server           FTP.INTERNIC.NET
 122          ;       -OR-                    RS.INTERNIC.NET
 123          ;
 124          ;       related version of root zone:   changes-on-20120103
 125          */
 126         struct delegpt* dp = delegpt_create_mlc((uint8_t*)"\000");
 127         if(!dp)
 128                 return NULL;
 129         dp->has_parent_side_NS = 1;
 130       if(do_ip4) {
 131         if(!ah(dp, "A.ROOT-SERVERS.NET.", "198.41.0.4"))        goto failed;
 132         if(!ah(dp, "B.ROOT-SERVERS.NET.", "192.228.79.201")) goto failed;
 133         if(!ah(dp, "C.ROOT-SERVERS.NET.", "192.33.4.12"))       goto failed;
 134         if(!ah(dp, "D.ROOT-SERVERS.NET.", "199.7.91.13"))       goto failed;
 135         if(!ah(dp, "E.ROOT-SERVERS.NET.", "192.203.230.10")) goto failed;
 136         if(!ah(dp, "F.ROOT-SERVERS.NET.", "192.5.5.241"))       goto failed;
 137         if(!ah(dp, "G.ROOT-SERVERS.NET.", "192.112.36.4"))      goto failed;
 138         if(!ah(dp, "H.ROOT-SERVERS.NET.", "198.97.190.53"))     goto failed;
 139         if(!ah(dp, "I.ROOT-SERVERS.NET.", "192.36.148.17"))     goto failed;
 140         if(!ah(dp, "J.ROOT-SERVERS.NET.", "192.58.128.30"))     goto failed;
 141         if(!ah(dp, "K.ROOT-SERVERS.NET.", "193.0.14.129"))      goto failed;
 142         if(!ah(dp, "L.ROOT-SERVERS.NET.", "199.7.83.42"))       goto failed;
 143         if(!ah(dp, "M.ROOT-SERVERS.NET.", "202.12.27.33"))      goto failed;
 144       }
 145       if(do_ip6) {
 146         if(!ah(dp, "A.ROOT-SERVERS.NET.", "2001:503:ba3e::2:30")) goto failed;
 147         if(!ah(dp, "B.ROOT-SERVERS.NET.", "2001:500:84::b")) goto failed;
 148         if(!ah(dp, "C.ROOT-SERVERS.NET.", "2001:500:2::c")) goto failed;
 149         if(!ah(dp, "D.ROOT-SERVERS.NET.", "2001:500:2d::d")) goto failed;
 150         if(!ah(dp, "E.ROOT-SERVERS.NET.", "2001:500:a8::e")) goto failed;
 151         if(!ah(dp, "F.ROOT-SERVERS.NET.", "2001:500:2f::f")) goto failed;
 152         if(!ah(dp, "H.ROOT-SERVERS.NET.", "2001:500:1::53")) goto failed;
 153         if(!ah(dp, "I.ROOT-SERVERS.NET.", "2001:7fe::53")) goto failed;
 154         if(!ah(dp, "J.ROOT-SERVERS.NET.", "2001:503:c27::2:30")) goto failed;
 155         if(!ah(dp, "K.ROOT-SERVERS.NET.", "2001:7fd::1")) goto failed;
 156         if(!ah(dp, "L.ROOT-SERVERS.NET.", "2001:500:9f::42")) goto failed;
 157         if(!ah(dp, "M.ROOT-SERVERS.NET.", "2001:dc3::35")) goto failed;
 158       }
 159         return dp;
 160 failed:
 161         delegpt_free_mlc(dp);
 162         return 0;
 163 }
 164
 165 /** insert new hint info into hint structure */
 166 static int
 167 hints_insert(struct iter_hints* hints, uint16_t c, struct delegpt* dp,
 168         int noprime)
 169 {
 170         struct iter_hints_stub* node = (struct iter_hints_stub*)malloc(
 171                 sizeof(struct iter_hints_stub));
 172         if(!node) {
 173                 delegpt_free_mlc(dp);
 174                 return 0;
 175         }
 176         node->dp = dp;
 177         node->noprime = (uint8_t)noprime;
 178         if(!name_tree_insert(&hints->tree, &node->node, dp->name, dp->namelen,
 179                 dp->namelabs, c)) {
 180                 char buf[257];
 181                 dname_str(dp->name, buf);
 182                 log_err("second hints for zone %s ignored.", buf);
 183                 delegpt_free_mlc(dp);
 184                 free(node);
 185         }
 186         return 1;
 187 }
 188
 189 /** set stub name */
 190 static struct delegpt*
 191 read_stubs_name(struct config_stub* s)
 192 {
 193         struct delegpt* dp;
 194         size_t dname_len;
 195         uint8_t* dname;
 196         if(!s->name) {
 197                 log_err("stub zone without a name");
 198                 return NULL;
 199         }
 200         dname = sldns_str2wire_dname(s->name, &dname_len);
 201         if(!dname) {
 202                 log_err("cannot parse stub zone name %s", s->name);
 203                 return NULL;
 204         }
 205         if(!(dp=delegpt_create_mlc(dname))) {
 206                 free(dname);
 207                 log_err("out of memory");
 208                 return NULL;
 209         }
 210         free(dname);
 211         return dp;
 212 }
 213
 214 /** set stub host names */
 215 static int
 216 read_stubs_host(struct config_stub* s, struct delegpt* dp)
 217 {
 218         struct config_strlist* p;
 219         size_t dname_len;
 220         uint8_t* dname;
 221         for(p = s->hosts; p; p = p->next) {
 222                 log_assert(p->str);
 223                 dname = sldns_str2wire_dname(p->str, &dname_len);
 224                 if(!dname) {
 225                         log_err("cannot parse stub %s nameserver name: '%s'",
 226                                 s->name, p->str);
 227                         return 0;
 228                 }
 229                 if(!delegpt_add_ns_mlc(dp, dname, 0)) {
 230                         free(dname);
 231                         log_err("out of memory");
 232                         return 0;
 233                 }
 234                 free(dname);
 235         }
 236         return 1;
 237 }
 238
 239 /** set stub server addresses */
 240 static int
 241 read_stubs_addr(struct config_stub* s, struct delegpt* dp)
 242 {
 243         struct config_strlist* p;
 244         struct sockaddr_storage addr;
 245         socklen_t addrlen;
 246         for(p = s->addrs; p; p = p->next) {
 247                 log_assert(p->str);
 248                 if(!extstrtoaddr(p->str, &addr, &addrlen)) {
 249                         log_err("cannot parse stub %s ip address: '%s'",
 250                                 s->name, p->str);
 251                         return 0;
 252                 }
 253                 if(!delegpt_add_addr_mlc(dp, &addr, addrlen, 0, 0)) {
 254                         log_err("out of memory");
 255                         return 0;
 256                 }
 257         }
 258         return 1;
 259 }
 260
 261 /** read stubs config */
 262 static int
 263 read_stubs(struct iter_hints* hints, struct config_file* cfg)
 264 {
 265         struct config_stub* s;
 266         struct delegpt* dp;
 267         for(s = cfg->stubs; s; s = s->next) {
 268                 if(!(dp=read_stubs_name(s)))
 269                         return 0;
 270                 if(!read_stubs_host(s, dp) || !read_stubs_addr(s, dp)) {
 271                         delegpt_free_mlc(dp);
 272                         return 0;
 273                 }
 274                 /* the flag is turned off for 'stub-first' so that the
 275                  * last resort will ask for parent-side NS record and thus
 276                  * fallback to the internet name servers on a failure */
 277                 dp->has_parent_side_NS = (uint8_t)!s->isfirst;
 278                 delegpt_log(VERB_QUERY, dp);
 279                 if(!hints_insert(hints, LDNS_RR_CLASS_IN, dp, !s->isprime))
 280                         return 0;
 281         }
 282         return 1;
 283 }
 284
 285 /** read root hints from file */
 286 static int
 287 read_root_hints(struct iter_hints* hints, char* fname)
 288 {
 289         struct sldns_file_parse_state pstate;
 290         struct delegpt* dp;
 291         uint8_t rr[LDNS_RR_BUF_SIZE];
 292         size_t rr_len, dname_len;
 293         int status;
 294         uint16_t c = LDNS_RR_CLASS_IN;
 295         FILE* f = fopen(fname, "r");
 296         if(!f) {
 297                 log_err("could not read root hints %s: %s",
 298                         fname, strerror(errno));
 299                 return 0;
 300         }
 301         dp = delegpt_create_mlc(NULL);
 302         if(!dp) {
 303                 log_err("out of memory reading root hints");
 304                 fclose(f);
 305                 return 0;
 306         }
 307         verbose(VERB_QUERY, "Reading root hints from %s", fname);
 308         memset(&pstate, 0, sizeof(pstate));
 309         pstate.lineno = 1;
 310         dp->has_parent_side_NS = 1;
 311         while(!feof(f)) {
 312                 rr_len = sizeof(rr);
 313                 dname_len = 0;
 314                 status = sldns_fp2wire_rr_buf(f, rr, &rr_len, &dname_len,
 315                         &pstate);
 316                 if(status != 0) {
 317                         log_err("reading root hints %s %d:%d: %s", fname,
 318                                 pstate.lineno, LDNS_WIREPARSE_OFFSET(status),
 319                                 sldns_get_errorstr_parse(status));
 320                         goto stop_read;
 321                 }
 322                 if(rr_len == 0)
 323                         continue; /* EMPTY line, TTL or ORIGIN */
 324                 if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 325                         == LDNS_RR_TYPE_NS) {
 326                         if(!delegpt_add_ns_mlc(dp, sldns_wirerr_get_rdata(rr,
 327                                 rr_len, dname_len), 0)) {
 328                                 log_err("out of memory reading root hints");
 329                                 goto stop_read;
 330                         }
 331                         c = sldns_wirerr_get_class(rr, rr_len, dname_len);
 332                         if(!dp->name) {
 333                                 if(!delegpt_set_name_mlc(dp, rr)) {
 334                                         log_err("out of memory.");
 335                                         goto stop_read;
 336                                 }
 337                         }
 338                 } else if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 339                         == LDNS_RR_TYPE_A && sldns_wirerr_get_rdatalen(rr,
 340                         rr_len, dname_len) == INET_SIZE) {
 341                         struct sockaddr_in sa;
 342                         socklen_t len = (socklen_t)sizeof(sa);
 343                         memset(&sa, 0, len);
 344                         sa.sin_family = AF_INET;
 345                         sa.sin_port = (in_port_t)htons(UNBOUND_DNS_PORT);
 346                         memmove(&sa.sin_addr,
 347                                 sldns_wirerr_get_rdata(rr, rr_len, dname_len),
 348                                 INET_SIZE);
 349                         if(!delegpt_add_target_mlc(dp, rr, dname_len,
 350                                         (struct sockaddr_storage*)&sa, len,
 351                                         0, 0)) {
 352                                 log_err("out of memory reading root hints");
 353                                 goto stop_read;
 354                         }
 355                 } else if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 356                         == LDNS_RR_TYPE_AAAA && sldns_wirerr_get_rdatalen(rr,
 357                         rr_len, dname_len) == INET6_SIZE) {
 358                         struct sockaddr_in6 sa;
 359                         socklen_t len = (socklen_t)sizeof(sa);
 360                         memset(&sa, 0, len);
 361                         sa.sin6_family = AF_INET6;
 362                         sa.sin6_port = (in_port_t)htons(UNBOUND_DNS_PORT);
 363                         memmove(&sa.sin6_addr,
 364                                 sldns_wirerr_get_rdata(rr, rr_len, dname_len),
 365                                 INET6_SIZE);
 366                         if(!delegpt_add_target_mlc(dp, rr, dname_len,
 367                                         (struct sockaddr_storage*)&sa, len,
 368                                         0, 0)) {
 369                                 log_err("out of memory reading root hints");
 370                                 goto stop_read;
 371                         }
 372                 } else {
 373                         char buf[17];
 374                         sldns_wire2str_type_buf(sldns_wirerr_get_type(rr,
 375                                 rr_len, dname_len), buf, sizeof(buf));
 376                         log_warn("root hints %s:%d skipping type %s",
 377                                 fname, pstate.lineno, buf);
 378                 }
 379         }
 380         fclose(f);
 381         if(!dp->name) {
 382                 log_warn("root hints %s: no NS content", fname);
 383                 delegpt_free_mlc(dp);
 384                 return 1;
 385         }
 386         if(!hints_insert(hints, c, dp, 0)) {
 387                 return 0;
 388         }
 389         delegpt_log(VERB_QUERY, dp);
 390         return 1;
 391
 392 stop_read:
 393         delegpt_free_mlc(dp);
 394         fclose(f);
 395         return 0;
 396 }
 397
 398 /** read root hints list */
 399 static int
 400 read_root_hints_list(struct iter_hints* hints, struct config_file* cfg)
 401 {
 402         struct config_strlist* p;
 403         for(p = cfg->root_hints; p; p = p->next) {
 404                 log_assert(p->str);
 405                 if(p->str && p->str[0]) {
 406                         char* f = p->str;
 407                         if(cfg->chrootdir && cfg->chrootdir[0] &&
 408                                 strncmp(p->str, cfg->chrootdir,
 409                                 strlen(cfg->chrootdir)) == 0)
 410                                 f += strlen(cfg->chrootdir);
 411                         if(!read_root_hints(hints, f))
 412                                 return 0;
 413                 }
 414         }
 415         return 1;
 416 }
 417
 418 int
 419 hints_apply_cfg(struct iter_hints* hints, struct config_file* cfg)
 420 {
 421         hints_del_tree(hints);
 422         name_tree_init(&hints->tree);
 423
 424         /* read root hints */
 425         if(!read_root_hints_list(hints, cfg))
 426                 return 0;
 427
 428         /* read stub hints */
 429         if(!read_stubs(hints, cfg))
 430                 return 0;
 431
 432         /* use fallback compiletime root hints */
 433         if(!hints_lookup_root(hints, LDNS_RR_CLASS_IN)) {
 434                 struct delegpt* dp = compile_time_root_prime(cfg->do_ip4,
 435                         cfg->do_ip6);
 436                 verbose(VERB_ALGO, "no config, using builtin root hints.");
 437                 if(!dp)
 438                         return 0;
 439                 if(!hints_insert(hints, LDNS_RR_CLASS_IN, dp, 0))
 440                         return 0;
 441         }
 442
 443         name_tree_init_parents(&hints->tree);
 444         return 1;
 445 }
 446
 447 struct delegpt*
 448 hints_lookup_root(struct iter_hints* hints, uint16_t qclass)
 449 {
 450         uint8_t rootlab = 0;
 451         struct iter_hints_stub *stub;
 452         stub = (struct iter_hints_stub*)name_tree_find(&hints->tree,
 453                 &rootlab, 1, 1, qclass);
 454         if(!stub)
 455                 return NULL;
 456         return stub->dp;
 457 }
 458
 459 struct iter_hints_stub*
 460 hints_lookup_stub(struct iter_hints* hints, uint8_t* qname,
 461         uint16_t qclass, struct delegpt* cache_dp)
 462 {
 463         size_t len;
 464         int labs;
 465         struct iter_hints_stub *r;
 466
 467         /* first lookup the stub */
 468         labs = dname_count_size_labels(qname, &len);
 469         r = (struct iter_hints_stub*)name_tree_lookup(&hints->tree, qname,
 470                 len, labs, qclass);
 471         if(!r) return NULL;
 472
 473         /* If there is no cache (root prime situation) */
 474         if(cache_dp == NULL) {
 475                 if(r->dp->namelabs != 1)
 476                         return r; /* no cache dp, use any non-root stub */
 477                 return NULL;
 478         }
 479
 480         /*
 481          * If the stub is same as the delegation we got
 482          * And has noprime set, we need to 'prime' to use this stub instead.
 483          */
 484         if(r->noprime && query_dname_compare(cache_dp->name, r->dp->name)==0)
 485                 return r; /* use this stub instead of cached dp */
 486
 487         /*
 488          * If our cached delegation point is above the hint, we need to prime.
 489          */
 490         if(dname_strict_subdomain(r->dp->name, r->dp->namelabs,
 491                 cache_dp->name, cache_dp->namelabs))
 492                 return r; /* need to prime this stub */
 493         return NULL;
 494 }
 495
 496 int hints_next_root(struct iter_hints* hints, uint16_t* qclass)
 497 {
 498         return name_tree_next_root(&hints->tree, qclass);
 499 }
 500
 501 size_t
 502 hints_get_mem(struct iter_hints* hints)
 503 {
 504         size_t s;
 505         struct iter_hints_stub* p;
 506         if(!hints) return 0;
 507         s = sizeof(*hints);
 508         RBTREE_FOR(p, struct iter_hints_stub*, &hints->tree) {
 509                 s += sizeof(*p) + delegpt_get_mem(p->dp);
 510         }
 511         return s;
 512 }
 513
 514 int
 515 hints_add_stub(struct iter_hints* hints, uint16_t c, struct delegpt* dp,
 516         int noprime)
 517 {
 518         struct iter_hints_stub *z;
 519         if((z=(struct iter_hints_stub*)name_tree_find(&hints->tree,
 520                 dp->name, dp->namelen, dp->namelabs, c)) != NULL) {
 521                 (void)rbtree_delete(&hints->tree, &z->node);
 522                 hints_stub_free(z);
 523         }
 524         if(!hints_insert(hints, c, dp, noprime))
 525                 return 0;
 526         name_tree_init_parents(&hints->tree);
 527         return 1;
 528 }
 529
 530 void
 531 hints_delete_stub(struct iter_hints* hints, uint16_t c, uint8_t* nm)
 532 {
 533         struct iter_hints_stub *z;
 534         size_t len;
 535         int labs = dname_count_size_labels(nm, &len);
 536         if(!(z=(struct iter_hints_stub*)name_tree_find(&hints->tree,
 537                 nm, len, labs, c)))
 538                 return; /* nothing to do */
 539         (void)rbtree_delete(&hints->tree, &z->node);
 540         hints_stub_free(z);
 541         name_tree_init_parents(&hints->tree);
 542 }
 543