contrib/ldns/drill/chasetrace.c

   1 /*
   2  * chasetrace.c
   3  * Where all the hard work concerning chasing
   4  * and tracing is done
   5  * (c) 2005, 2006 NLnet Labs
   6  *
   7  * See the file LICENSE for the license
   8  *
   9  */
  10
  11 #include "drill.h"
  12 #include <ldns/ldns.h>
  13
  14 /**
  15  * trace down from the root to name
  16  */
  17
  18 /* same naive method as in drill0.9
  19  * We resolver _ALL_ the names, which is ofcourse not needed
  20  * We _do_ use the local resolver to do that, so it still is
  21  * fast, but it can be made to run much faster
  22  */
  23 ldns_pkt *
  24 do_trace(ldns_resolver *local_res, ldns_rdf *name, ldns_rr_type t,
  25                 ldns_rr_class c)
  26 {
  27         ldns_resolver *res;
  28         ldns_pkt *p;
  29         ldns_rr_list *new_nss_a;
  30         ldns_rr_list *new_nss_aaaa;
  31         ldns_rr_list *final_answer;
  32         ldns_rr_list *new_nss;
  33         ldns_rr_list *ns_addr;
  34         uint16_t loop_count;
  35         ldns_rdf *pop;
  36         ldns_status status;
  37         size_t i;
  38
  39         loop_count = 0;
  40         new_nss_a = NULL;
  41         new_nss_aaaa = NULL;
  42         new_nss = NULL;
  43         ns_addr = NULL;
  44         final_answer = NULL;
  45         p = ldns_pkt_new();
  46         res = ldns_resolver_new();
  47
  48         if (!p) {
  49                 if (res) {
  50                         ldns_resolver_free(res);
  51                 }
  52                 error("Memory allocation failed");
  53                 return NULL;
  54         }
  55         if (!res) {
  56                 ldns_pkt_free(p);
  57                 error("Memory allocation failed");
  58                 return NULL;
  59         }
  60
  61         /* transfer some properties of local_res to res,
  62          * because they were given on the commandline */
  63         ldns_resolver_set_ip6(res,
  64                         ldns_resolver_ip6(local_res));
  65         ldns_resolver_set_port(res,
  66                         ldns_resolver_port(local_res));
  67         ldns_resolver_set_debug(res,
  68                         ldns_resolver_debug(local_res));
  69         ldns_resolver_set_dnssec(res,
  70                         ldns_resolver_dnssec(local_res));
  71         ldns_resolver_set_fail(res,
  72                         ldns_resolver_fail(local_res));
  73         ldns_resolver_set_usevc(res,
  74                         ldns_resolver_usevc(local_res));
  75         ldns_resolver_set_random(res,
  76                         ldns_resolver_random(local_res));
  77         ldns_resolver_set_recursive(res, false);
  78
  79         /* setup the root nameserver in the new resolver */
  80         status = ldns_resolver_push_nameserver_rr_list(res, global_dns_root);
  81         if (status != LDNS_STATUS_OK) {
  82                 fprintf(stderr, "Error adding root servers to resolver: %s\n", ldns_get_errorstr_by_id(status));
  83                 ldns_rr_list_print(stdout, global_dns_root);
  84                 ldns_resolver_free(res);
  85                 ldns_pkt_free(p);
  86                 return NULL;
  87         }
  88
  89         /* this must be a real query to local_res */
  90         status = ldns_resolver_send(&p, res, ldns_dname_new_frm_str("."), LDNS_RR_TYPE_NS, c, 0);
  91         /* p can still be NULL */
  92
  93
  94         if (ldns_pkt_empty(p)) {
  95                 warning("No root server information received");
  96         }
  97
  98         if (status == LDNS_STATUS_OK) {
  99                 if (!ldns_pkt_empty(p)) {
 100                         drill_pkt_print(stdout, local_res, p);
 101                 }
 102         } else {
 103                 error("cannot use local resolver");
 104                 return NULL;
 105         }
 106
 107         status = ldns_resolver_send(&p, res, name, t, c, 0);
 108
 109         while(status == LDNS_STATUS_OK &&
 110               ldns_pkt_reply_type(p) == LDNS_PACKET_REFERRAL) {
 111
 112                 if (!p) {
 113                         /* some error occurred, bail out */
 114                         return NULL;
 115                 }
 116
 117                 new_nss_a = ldns_pkt_rr_list_by_type(p,
 118                                 LDNS_RR_TYPE_A, LDNS_SECTION_ADDITIONAL);
 119                 new_nss_aaaa = ldns_pkt_rr_list_by_type(p,
 120                                 LDNS_RR_TYPE_AAAA, LDNS_SECTION_ADDITIONAL);
 121                 new_nss = ldns_pkt_rr_list_by_type(p,
 122                                 LDNS_RR_TYPE_NS, LDNS_SECTION_AUTHORITY);
 123
 124                 if (verbosity != -1) {
 125                         ldns_rr_list_print(stdout, new_nss);
 126                 }
 127                 /* checks itself for verbosity */
 128                 drill_pkt_print_footer(stdout, local_res, p);
 129
 130                 /* remove the old nameserver from the resolver */
 131                 while(ldns_resolver_pop_nameserver(res)) { /* do it */ }
 132
 133                 /* also check for new_nss emptyness */
 134
 135                 if (!new_nss_aaaa && !new_nss_a) {
 136                         /*
 137                          * no nameserver found!!!
 138                          * try to resolve the names we do got
 139                          */
 140                         for(i = 0; i < ldns_rr_list_rr_count(new_nss); i++) {
 141                                 /* get the name of the nameserver */
 142                                 pop = ldns_rr_rdf(ldns_rr_list_rr(new_nss, i), 0);
 143                                 if (!pop) {
 144                                         break;
 145                                 }
 146
 147                                 ldns_rr_list_print(stdout, new_nss);
 148                                 ldns_rdf_print(stdout, pop);
 149                                 /* retrieve it's addresses */
 150                                 ns_addr = ldns_rr_list_cat_clone(ns_addr,
 151                                         ldns_get_rr_list_addr_by_name(local_res, pop, c, 0));
 152                         }
 153
 154                         if (ns_addr) {
 155                                 if (ldns_resolver_push_nameserver_rr_list(res, ns_addr) !=
 156                                                 LDNS_STATUS_OK) {
 157                                         error("Error adding new nameservers");
 158                                         ldns_pkt_free(p);
 159                                         return NULL;
 160                                 }
 161                                 ldns_rr_list_free(ns_addr);
 162                         } else {
 163                                 ldns_rr_list_print(stdout, ns_addr);
 164                                 error("Could not find the nameserver ip addr; abort");
 165                                 ldns_pkt_free(p);
 166                                 return NULL;
 167                         }
 168                 }
 169
 170                 /* add the new ones */
 171                 if (new_nss_aaaa) {
 172                         if (ldns_resolver_push_nameserver_rr_list(res, new_nss_aaaa) !=
 173                                         LDNS_STATUS_OK) {
 174                                 error("adding new nameservers");
 175                                 ldns_pkt_free(p);
 176                                 return NULL;
 177                         }
 178                 }
 179                 if (new_nss_a) {
 180                         if (ldns_resolver_push_nameserver_rr_list(res, new_nss_a) !=
 181                                         LDNS_STATUS_OK) {
 182                                 error("adding new nameservers");
 183                                 ldns_pkt_free(p);
 184                                 return NULL;
 185                         }
 186                 }
 187
 188                 if (loop_count++ > 20) {
 189                         /* unlikely that we are doing something usefull */
 190                         error("Looks like we are looping");
 191                         ldns_pkt_free(p);
 192                         return NULL;
 193                 }
 194
 195                 status = ldns_resolver_send(&p, res, name, t, c, 0);
 196                 new_nss_aaaa = NULL;
 197                 new_nss_a = NULL;
 198                 ns_addr = NULL;
 199         }
 200
 201         status = ldns_resolver_send(&p, res, name, t, c, 0);
 202
 203         if (!p) {
 204                 return NULL;
 205         }
 206
 207         new_nss = ldns_pkt_authority(p);
 208         final_answer = ldns_pkt_answer(p);
 209
 210         if (verbosity != -1) {
 211                 ldns_rr_list_print(stdout, final_answer);
 212                 ldns_rr_list_print(stdout, new_nss);
 213
 214         }
 215         drill_pkt_print_footer(stdout, local_res, p);
 216         ldns_pkt_free(p);
 217         return NULL;
 218 }
 219
 220
 221 /**
 222  * Chase the given rr to a known and trusted key
 223  *
 224  * Based on drill 0.9
 225  *
 226  * the last argument prev_key_list, if not null, and type == DS, then the ds
 227  * rr list we have must all be a ds for the keys in this list
 228  */
 229 #ifdef HAVE_SSL
 230 ldns_status
 231 do_chase(ldns_resolver *res,
 232             ldns_rdf *name,
 233             ldns_rr_type type,
 234             ldns_rr_class c,
 235             ldns_rr_list *trusted_keys,
 236             ldns_pkt *pkt_o,
 237             uint16_t qflags,
 238             ldns_rr_list * ATTR_UNUSED(prev_key_list),
 239             int verbosity)
 240 {
 241         ldns_rr_list *rrset = NULL;
 242         ldns_status result;
 243         ldns_rr *orig_rr = NULL;
 244
 245 /*
 246         ldns_rr_list *sigs;
 247         ldns_rr *cur_sig;
 248         uint16_t sig_i;
 249         ldns_rr_list *keys;
 250 */
 251         ldns_pkt *pkt;
 252         ldns_status tree_result;
 253         ldns_dnssec_data_chain *chain;
 254         ldns_dnssec_trust_tree *tree;
 255
 256         const ldns_rr_descriptor *descriptor;
 257         descriptor = ldns_rr_descript(type);
 258
 259         ldns_dname2canonical(name);
 260
 261         pkt = ldns_pkt_clone(pkt_o);
 262         if (!name) {
 263                 mesg("No name to chase");
 264                 ldns_pkt_free(pkt);
 265                 return LDNS_STATUS_EMPTY_LABEL;
 266         }
 267         if (verbosity != -1) {
 268                 printf(";; Chasing: ");
 269                         ldns_rdf_print(stdout, name);
 270                         if (descriptor && descriptor->_name) {
 271                                 printf(" %s\n", descriptor->_name);
 272                         } else {
 273                                 printf(" type %d\n", type);
 274                         }
 275         }
 276
 277         if (!trusted_keys || ldns_rr_list_rr_count(trusted_keys) < 1) {
 278                 warning("No trusted keys specified");
 279         }
 280
 281         if (pkt) {
 282                 rrset = ldns_pkt_rr_list_by_name_and_type(pkt,
 283                                 name,
 284                                 type,
 285                                 LDNS_SECTION_ANSWER
 286                                 );
 287                 if (!rrset) {
 288                         /* nothing in answer, try authority */
 289                         rrset = ldns_pkt_rr_list_by_name_and_type(pkt,
 290                                         name,
 291                                         type,
 292                                         LDNS_SECTION_AUTHORITY
 293                                         );
 294                 }
 295                 /* answer might be a cname, chase that first, then chase
 296                    cname target? (TODO) */
 297                 if (!rrset) {
 298                         rrset = ldns_pkt_rr_list_by_name_and_type(pkt,
 299                                         name,
 300                                         LDNS_RR_TYPE_CNAME,
 301                                         LDNS_SECTION_ANSWER
 302                                         );
 303                         if (!rrset) {
 304                                 /* nothing in answer, try authority */
 305                                 rrset = ldns_pkt_rr_list_by_name_and_type(pkt,
 306                                                 name,
 307                                                 LDNS_RR_TYPE_CNAME,
 308                                                 LDNS_SECTION_AUTHORITY
 309                                                 );
 310                         }
 311                 }
 312         } else {
 313                 /* no packet? */
 314                 if (verbosity >= 0) {
 315                         fprintf(stderr, "%s", ldns_get_errorstr_by_id(LDNS_STATUS_MEM_ERR));
 316                         fprintf(stderr, "\n");
 317                 }
 318                 return LDNS_STATUS_MEM_ERR;
 319         }
 320
 321         if (!rrset) {
 322                 /* not found in original packet, try again */
 323                 ldns_pkt_free(pkt);
 324                 pkt = NULL;
 325                 pkt = ldns_resolver_query(res, name, type, c, qflags);
 326
 327                 if (!pkt) {
 328                         if (verbosity >= 0) {
 329                                 fprintf(stderr, "%s", ldns_get_errorstr_by_id(LDNS_STATUS_NETWORK_ERR));
 330                                 fprintf(stderr, "\n");
 331                         }
 332                         return LDNS_STATUS_NETWORK_ERR;
 333                 }
 334                 if (verbosity >= 5) {
 335                         ldns_pkt_print(stdout, pkt);
 336                 }
 337
 338                 rrset = ldns_pkt_rr_list_by_name_and_type(pkt,
 339                                 name,
 340                                 type,
 341                                 LDNS_SECTION_ANSWER
 342                                 );
 343         }
 344
 345         orig_rr = ldns_rr_new();
 346
 347 /* if the answer had no answer section, we need to construct our own rr (for instance if
 348  * the rr qe asked for doesn't exist. This rr will be destroyed when the chain is freed */
 349         if (ldns_pkt_ancount(pkt) < 1) {
 350                 ldns_rr_set_type(orig_rr, type);
 351                 ldns_rr_set_owner(orig_rr, ldns_rdf_clone(name));
 352
 353                 chain = ldns_dnssec_build_data_chain(res, qflags, rrset, pkt, ldns_rr_clone(orig_rr));
 354         } else {
 355                 /* chase the first answer */
 356                 chain = ldns_dnssec_build_data_chain(res, qflags, rrset, pkt, NULL);
 357         }
 358
 359         if (verbosity >= 4) {
 360                 printf("\n\nDNSSEC Data Chain:\n");
 361                 ldns_dnssec_data_chain_print(stdout, chain);
 362         }
 363
 364         result = LDNS_STATUS_OK;
 365
 366         tree = ldns_dnssec_derive_trust_tree(chain, NULL);
 367
 368         if (verbosity >= 2) {
 369                 printf("\n\nDNSSEC Trust tree:\n");
 370                 ldns_dnssec_trust_tree_print(stdout, tree, 0, true);
 371         }
 372
 373         if (ldns_rr_list_rr_count(trusted_keys) > 0) {
 374                 tree_result = ldns_dnssec_trust_tree_contains_keys(tree, trusted_keys);
 375
 376                 if (tree_result == LDNS_STATUS_DNSSEC_EXISTENCE_DENIED) {
 377                         if (verbosity >= 1) {
 378                                 printf("Existence denied or verifiably insecure\n");
 379                         }
 380                         result = LDNS_STATUS_OK;
 381                 } else if (tree_result != LDNS_STATUS_OK) {
 382                         if (verbosity >= 1) {
 383                                 printf("No trusted keys found in tree: first error was: %s\n", ldns_get_errorstr_by_id(tree_result));
 384                         }
 385                         result = tree_result;
 386                 }
 387
 388         } else {
 389                 if (verbosity >= 0) {
 390                         printf("You have not provided any trusted keys.\n");
 391                 }
 392         }
 393
 394         ldns_rr_free(orig_rr);
 395         ldns_dnssec_trust_tree_free(tree);
 396         ldns_dnssec_data_chain_deep_free(chain);
 397
 398         ldns_rr_list_deep_free(rrset);
 399         ldns_pkt_free(pkt);
 400         /*      ldns_rr_free(orig_rr);*/
 401
 402         return result;
 403 }
 404 #endif /* HAVE_SSL */
 405