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, "G.ROOT-SERVERS.NET.", "2001:500:12::d0d")) goto failed;
 153         if(!ah(dp, "H.ROOT-SERVERS.NET.", "2001:500:1::53")) goto failed;
 154         if(!ah(dp, "I.ROOT-SERVERS.NET.", "2001:7fe::53")) goto failed;
 155         if(!ah(dp, "J.ROOT-SERVERS.NET.", "2001:503:c27::2:30")) goto failed;
 156         if(!ah(dp, "K.ROOT-SERVERS.NET.", "2001:7fd::1")) goto failed;
 157         if(!ah(dp, "L.ROOT-SERVERS.NET.", "2001:500:9f::42")) goto failed;
 158         if(!ah(dp, "M.ROOT-SERVERS.NET.", "2001:dc3::35")) goto failed;
 159       }
 160         return dp;
 161 failed:
 162         delegpt_free_mlc(dp);
 163         return 0;
 164 }
 165
 166 /** insert new hint info into hint structure */
 167 static int
 168 hints_insert(struct iter_hints* hints, uint16_t c, struct delegpt* dp,
 169         int noprime)
 170 {
 171         struct iter_hints_stub* node = (struct iter_hints_stub*)malloc(
 172                 sizeof(struct iter_hints_stub));
 173         if(!node) {
 174                 delegpt_free_mlc(dp);
 175                 return 0;
 176         }
 177         node->dp = dp;
 178         node->noprime = (uint8_t)noprime;
 179         if(!name_tree_insert(&hints->tree, &node->node, dp->name, dp->namelen,
 180                 dp->namelabs, c)) {
 181                 char buf[257];
 182                 dname_str(dp->name, buf);
 183                 log_err("second hints for zone %s ignored.", buf);
 184                 delegpt_free_mlc(dp);
 185                 free(node);
 186         }
 187         return 1;
 188 }
 189
 190 /** set stub name */
 191 static struct delegpt*
 192 read_stubs_name(struct config_stub* s)
 193 {
 194         struct delegpt* dp;
 195         size_t dname_len;
 196         uint8_t* dname;
 197         if(!s->name) {
 198                 log_err("stub zone without a name");
 199                 return NULL;
 200         }
 201         dname = sldns_str2wire_dname(s->name, &dname_len);
 202         if(!dname) {
 203                 log_err("cannot parse stub zone name %s", s->name);
 204                 return NULL;
 205         }
 206         if(!(dp=delegpt_create_mlc(dname))) {
 207                 free(dname);
 208                 log_err("out of memory");
 209                 return NULL;
 210         }
 211         free(dname);
 212         return dp;
 213 }
 214
 215 /** set stub host names */
 216 static int
 217 read_stubs_host(struct config_stub* s, struct delegpt* dp)
 218 {
 219         struct config_strlist* p;
 220         size_t dname_len;
 221         uint8_t* dname;
 222         for(p = s->hosts; p; p = p->next) {
 223                 log_assert(p->str);
 224                 dname = sldns_str2wire_dname(p->str, &dname_len);
 225                 if(!dname) {
 226                         log_err("cannot parse stub %s nameserver name: '%s'",
 227                                 s->name, p->str);
 228                         return 0;
 229                 }
 230                 if(!delegpt_add_ns_mlc(dp, dname, 0)) {
 231                         free(dname);
 232                         log_err("out of memory");
 233                         return 0;
 234                 }
 235                 free(dname);
 236         }
 237         return 1;
 238 }
 239
 240 /** set stub server addresses */
 241 static int
 242 read_stubs_addr(struct config_stub* s, struct delegpt* dp)
 243 {
 244         struct config_strlist* p;
 245         struct sockaddr_storage addr;
 246         socklen_t addrlen;
 247         for(p = s->addrs; p; p = p->next) {
 248                 log_assert(p->str);
 249                 if(!extstrtoaddr(p->str, &addr, &addrlen)) {
 250                         log_err("cannot parse stub %s ip address: '%s'",
 251                                 s->name, p->str);
 252                         return 0;
 253                 }
 254                 if(!delegpt_add_addr_mlc(dp, &addr, addrlen, 0, 0)) {
 255                         log_err("out of memory");
 256                         return 0;
 257                 }
 258         }
 259         return 1;
 260 }
 261
 262 /** read stubs config */
 263 static int
 264 read_stubs(struct iter_hints* hints, struct config_file* cfg)
 265 {
 266         struct config_stub* s;
 267         struct delegpt* dp;
 268         for(s = cfg->stubs; s; s = s->next) {
 269                 if(!(dp=read_stubs_name(s)))
 270                         return 0;
 271                 if(!read_stubs_host(s, dp) || !read_stubs_addr(s, dp)) {
 272                         delegpt_free_mlc(dp);
 273                         return 0;
 274                 }
 275                 /* the flag is turned off for 'stub-first' so that the
 276                  * last resort will ask for parent-side NS record and thus
 277                  * fallback to the internet name servers on a failure */
 278                 dp->has_parent_side_NS = (uint8_t)!s->isfirst;
 279                 /* ssl_upstream */
 280                 dp->ssl_upstream = (uint8_t)s->ssl_upstream;
 281                 delegpt_log(VERB_QUERY, dp);
 282                 if(!hints_insert(hints, LDNS_RR_CLASS_IN, dp, !s->isprime))
 283                         return 0;
 284         }
 285         return 1;
 286 }
 287
 288 /** read root hints from file */
 289 static int
 290 read_root_hints(struct iter_hints* hints, char* fname)
 291 {
 292         struct sldns_file_parse_state pstate;
 293         struct delegpt* dp;
 294         uint8_t rr[LDNS_RR_BUF_SIZE];
 295         size_t rr_len, dname_len;
 296         int status;
 297         uint16_t c = LDNS_RR_CLASS_IN;
 298         FILE* f = fopen(fname, "r");
 299         if(!f) {
 300                 log_err("could not read root hints %s: %s",
 301                         fname, strerror(errno));
 302                 return 0;
 303         }
 304         dp = delegpt_create_mlc(NULL);
 305         if(!dp) {
 306                 log_err("out of memory reading root hints");
 307                 fclose(f);
 308                 return 0;
 309         }
 310         verbose(VERB_QUERY, "Reading root hints from %s", fname);
 311         memset(&pstate, 0, sizeof(pstate));
 312         pstate.lineno = 1;
 313         dp->has_parent_side_NS = 1;
 314         while(!feof(f)) {
 315                 rr_len = sizeof(rr);
 316                 dname_len = 0;
 317                 status = sldns_fp2wire_rr_buf(f, rr, &rr_len, &dname_len,
 318                         &pstate);
 319                 if(status != 0) {
 320                         log_err("reading root hints %s %d:%d: %s", fname,
 321                                 pstate.lineno, LDNS_WIREPARSE_OFFSET(status),
 322                                 sldns_get_errorstr_parse(status));
 323                         goto stop_read;
 324                 }
 325                 if(rr_len == 0)
 326                         continue; /* EMPTY line, TTL or ORIGIN */
 327                 if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 328                         == LDNS_RR_TYPE_NS) {
 329                         if(!delegpt_add_ns_mlc(dp, sldns_wirerr_get_rdata(rr,
 330                                 rr_len, dname_len), 0)) {
 331                                 log_err("out of memory reading root hints");
 332                                 goto stop_read;
 333                         }
 334                         c = sldns_wirerr_get_class(rr, rr_len, dname_len);
 335                         if(!dp->name) {
 336                                 if(!delegpt_set_name_mlc(dp, rr)) {
 337                                         log_err("out of memory.");
 338                                         goto stop_read;
 339                                 }
 340                         }
 341                 } else if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 342                         == LDNS_RR_TYPE_A && sldns_wirerr_get_rdatalen(rr,
 343                         rr_len, dname_len) == INET_SIZE) {
 344                         struct sockaddr_in sa;
 345                         socklen_t len = (socklen_t)sizeof(sa);
 346                         memset(&sa, 0, len);
 347                         sa.sin_family = AF_INET;
 348                         sa.sin_port = (in_port_t)htons(UNBOUND_DNS_PORT);
 349                         memmove(&sa.sin_addr,
 350                                 sldns_wirerr_get_rdata(rr, rr_len, dname_len),
 351                                 INET_SIZE);
 352                         if(!delegpt_add_target_mlc(dp, rr, dname_len,
 353                                         (struct sockaddr_storage*)&sa, len,
 354                                         0, 0)) {
 355                                 log_err("out of memory reading root hints");
 356                                 goto stop_read;
 357                         }
 358                 } else if(sldns_wirerr_get_type(rr, rr_len, dname_len)
 359                         == LDNS_RR_TYPE_AAAA && sldns_wirerr_get_rdatalen(rr,
 360                         rr_len, dname_len) == INET6_SIZE) {
 361                         struct sockaddr_in6 sa;
 362                         socklen_t len = (socklen_t)sizeof(sa);
 363                         memset(&sa, 0, len);
 364                         sa.sin6_family = AF_INET6;
 365                         sa.sin6_port = (in_port_t)htons(UNBOUND_DNS_PORT);
 366                         memmove(&sa.sin6_addr,
 367                                 sldns_wirerr_get_rdata(rr, rr_len, dname_len),
 368                                 INET6_SIZE);
 369                         if(!delegpt_add_target_mlc(dp, rr, dname_len,
 370                                         (struct sockaddr_storage*)&sa, len,
 371                                         0, 0)) {
 372                                 log_err("out of memory reading root hints");
 373                                 goto stop_read;
 374                         }
 375                 } else {
 376                         char buf[17];
 377                         sldns_wire2str_type_buf(sldns_wirerr_get_type(rr,
 378                                 rr_len, dname_len), buf, sizeof(buf));
 379                         log_warn("root hints %s:%d skipping type %s",
 380                                 fname, pstate.lineno, buf);
 381                 }
 382         }
 383         fclose(f);
 384         if(!dp->name) {
 385                 log_warn("root hints %s: no NS content", fname);
 386                 delegpt_free_mlc(dp);
 387                 return 1;
 388         }
 389         if(!hints_insert(hints, c, dp, 0)) {
 390                 return 0;
 391         }
 392         delegpt_log(VERB_QUERY, dp);
 393         return 1;
 394
 395 stop_read:
 396         delegpt_free_mlc(dp);
 397         fclose(f);
 398         return 0;
 399 }
 400
 401 /** read root hints list */
 402 static int
 403 read_root_hints_list(struct iter_hints* hints, struct config_file* cfg)
 404 {
 405         struct config_strlist* p;
 406         for(p = cfg->root_hints; p; p = p->next) {
 407                 log_assert(p->str);
 408                 if(p->str && p->str[0]) {
 409                         char* f = p->str;
 410                         if(cfg->chrootdir && cfg->chrootdir[0] &&
 411                                 strncmp(p->str, cfg->chrootdir,
 412                                 strlen(cfg->chrootdir)) == 0)
 413                                 f += strlen(cfg->chrootdir);
 414                         if(!read_root_hints(hints, f))
 415                                 return 0;
 416                 }
 417         }
 418         return 1;
 419 }
 420
 421 int
 422 hints_apply_cfg(struct iter_hints* hints, struct config_file* cfg)
 423 {
 424         hints_del_tree(hints);
 425         name_tree_init(&hints->tree);
 426
 427         /* read root hints */
 428         if(!read_root_hints_list(hints, cfg))
 429                 return 0;
 430
 431         /* read stub hints */
 432         if(!read_stubs(hints, cfg))
 433                 return 0;
 434
 435         /* use fallback compiletime root hints */
 436         if(!hints_lookup_root(hints, LDNS_RR_CLASS_IN)) {
 437                 struct delegpt* dp = compile_time_root_prime(cfg->do_ip4,
 438                         cfg->do_ip6);
 439                 verbose(VERB_ALGO, "no config, using builtin root hints.");
 440                 if(!dp)
 441                         return 0;
 442                 if(!hints_insert(hints, LDNS_RR_CLASS_IN, dp, 0))
 443                         return 0;
 444         }
 445
 446         name_tree_init_parents(&hints->tree);
 447         return 1;
 448 }
 449
 450 struct delegpt*
 451 hints_lookup_root(struct iter_hints* hints, uint16_t qclass)
 452 {
 453         uint8_t rootlab = 0;
 454         struct iter_hints_stub *stub;
 455         stub = (struct iter_hints_stub*)name_tree_find(&hints->tree,
 456                 &rootlab, 1, 1, qclass);
 457         if(!stub)
 458                 return NULL;
 459         return stub->dp;
 460 }
 461
 462 struct iter_hints_stub*
 463 hints_lookup_stub(struct iter_hints* hints, uint8_t* qname,
 464         uint16_t qclass, struct delegpt* cache_dp)
 465 {
 466         size_t len;
 467         int labs;
 468         struct iter_hints_stub *r;
 469
 470         /* first lookup the stub */
 471         labs = dname_count_size_labels(qname, &len);
 472         r = (struct iter_hints_stub*)name_tree_lookup(&hints->tree, qname,
 473                 len, labs, qclass);
 474         if(!r) return NULL;
 475
 476         /* If there is no cache (root prime situation) */
 477         if(cache_dp == NULL) {
 478                 if(r->dp->namelabs != 1)
 479                         return r; /* no cache dp, use any non-root stub */
 480                 return NULL;
 481         }
 482
 483         /*
 484          * If the stub is same as the delegation we got
 485          * And has noprime set, we need to 'prime' to use this stub instead.
 486          */
 487         if(r->noprime && query_dname_compare(cache_dp->name, r->dp->name)==0)
 488                 return r; /* use this stub instead of cached dp */
 489
 490         /*
 491          * If our cached delegation point is above the hint, we need to prime.
 492          */
 493         if(dname_strict_subdomain(r->dp->name, r->dp->namelabs,
 494                 cache_dp->name, cache_dp->namelabs))
 495                 return r; /* need to prime this stub */
 496         return NULL;
 497 }
 498
 499 int hints_next_root(struct iter_hints* hints, uint16_t* qclass)
 500 {
 501         return name_tree_next_root(&hints->tree, qclass);
 502 }
 503
 504 size_t
 505 hints_get_mem(struct iter_hints* hints)
 506 {
 507         size_t s;
 508         struct iter_hints_stub* p;
 509         if(!hints) return 0;
 510         s = sizeof(*hints);
 511         RBTREE_FOR(p, struct iter_hints_stub*, &hints->tree) {
 512                 s += sizeof(*p) + delegpt_get_mem(p->dp);
 513         }
 514         return s;
 515 }
 516
 517 int
 518 hints_add_stub(struct iter_hints* hints, uint16_t c, struct delegpt* dp,
 519         int noprime)
 520 {
 521         struct iter_hints_stub *z;
 522         if((z=(struct iter_hints_stub*)name_tree_find(&hints->tree,
 523                 dp->name, dp->namelen, dp->namelabs, c)) != NULL) {
 524                 (void)rbtree_delete(&hints->tree, &z->node);
 525                 hints_stub_free(z);
 526         }
 527         if(!hints_insert(hints, c, dp, noprime))
 528                 return 0;
 529         name_tree_init_parents(&hints->tree);
 530         return 1;
 531 }
 532
 533 void
 534 hints_delete_stub(struct iter_hints* hints, uint16_t c, uint8_t* nm)
 535 {
 536         struct iter_hints_stub *z;
 537         size_t len;
 538         int labs = dname_count_size_labels(nm, &len);
 539         if(!(z=(struct iter_hints_stub*)name_tree_find(&hints->tree,
 540                 nm, len, labs, c)))
 541                 return; /* nothing to do */
 542         (void)rbtree_delete(&hints->tree, &z->node);
 543         hints_stub_free(z);
 544         name_tree_init_parents(&hints->tree);
 545 }
 546