contrib/ldns/zone.c

   1 /* zone.c
   2  *
   3  * Functions for ldns_zone structure
   4  * a Net::DNS like library for C
   5  *
   6  * (c) NLnet Labs, 2005-2006
   7  * See the file LICENSE for the license
   8  */
   9 #include <ldns/config.h>
  10
  11 #include <ldns/ldns.h>
  12
  13 #include <strings.h>
  14 #include <limits.h>
  15
  16 ldns_rr *
  17 ldns_zone_soa(const ldns_zone *z)
  18 {
  19         return z->_soa;
  20 }
  21
  22 size_t
  23 ldns_zone_rr_count(const ldns_zone *z)
  24 {
  25         return ldns_rr_list_rr_count(z->_rrs);
  26 }
  27
  28 void
  29 ldns_zone_set_soa(ldns_zone *z, ldns_rr *soa)
  30 {
  31         z->_soa = soa;
  32 }
  33
  34 ldns_rr_list *
  35 ldns_zone_rrs(const ldns_zone *z)
  36 {
  37         return z->_rrs;
  38 }
  39
  40 void
  41 ldns_zone_set_rrs(ldns_zone *z, ldns_rr_list *rrlist)
  42 {
  43         z->_rrs = rrlist;
  44 }
  45
  46 bool
  47 ldns_zone_push_rr_list(ldns_zone *z, ldns_rr_list *list)
  48 {
  49         return ldns_rr_list_cat(ldns_zone_rrs(z), list);
  50
  51 }
  52
  53 bool
  54 ldns_zone_push_rr(ldns_zone *z, ldns_rr *rr)
  55 {
  56         return ldns_rr_list_push_rr( ldns_zone_rrs(z), rr);
  57 }
  58
  59 /* return a clone of the given rr list, without the glue records
  60  * rr list should be the complete zone
  61  * if present, stripped records are added to the list *glue_records
  62  */
  63 ldns_rr_list *
  64 ldns_zone_strip_glue_rrs(const ldns_rdf *zone_name, const ldns_rr_list *rrs, ldns_rr_list *glue_rrs)
  65 {
  66         ldns_rr_list *new_list;
  67
  68         /* when do we find glue? It means we find an IP address
  69          * (AAAA/A) for a nameserver listed in the zone
  70          *
  71          * Alg used here:
  72          * first find all the zonecuts (NS records)
  73          * find all the AAAA or A records (can be done it the
  74          * above loop).
  75          *
  76          * Check if the aaaa/a list are subdomains under the
  77          * NS domains.
  78          * If yes -> glue, if no -> not glue
  79          */
  80
  81         ldns_rr_list *zone_cuts;
  82         ldns_rr_list *addr;
  83         ldns_rr *r, *ns, *a;
  84         ldns_rdf *dname_a, *ns_owner;
  85         uint16_t i,j;
  86
  87         new_list = NULL;
  88         zone_cuts = NULL;
  89         addr = NULL;
  90
  91         new_list = ldns_rr_list_new();
  92         if (!new_list) goto memory_error;
  93         zone_cuts = ldns_rr_list_new();
  94         if (!zone_cuts) goto memory_error;
  95         addr = ldns_rr_list_new();
  96         if (!addr) goto memory_error;
  97
  98         for(i = 0; i < ldns_rr_list_rr_count(rrs); i++) {
  99                 r = ldns_rr_list_rr(rrs, i);
 100                 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
 101                                 ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
 102                         /* possibly glue */
 103                         if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
 104                         continue;
 105                 }
 106                 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
 107                         /* multiple zones will end up here -
 108                          * for now; not a problem
 109                          */
 110                         /* don't add NS records for the current zone itself */
 111                         if (ldns_rdf_compare(ldns_rr_owner(r),
 112                                                 zone_name) != 0) {
 113                                 if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
 114                         }
 115                         continue;
 116                 }
 117         }
 118
 119         /* will sorting make it quicker ?? */
 120         for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
 121                 ns = ldns_rr_list_rr(zone_cuts, i);
 122                 ns_owner = ldns_rr_owner(ns);
 123                 for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
 124                         a = ldns_rr_list_rr(addr, j);
 125                         dname_a = ldns_rr_owner(a);
 126
 127                         if (ldns_dname_is_subdomain(dname_a, ns_owner)) {
 128                                 /* GLUE! */
 129                                 if (glue_rrs) {
 130                                         if (!ldns_rr_list_push_rr(glue_rrs, a)) goto memory_error;
 131                                 }
 132                                 break;
 133                         } else {
 134                                 if (!ldns_rr_list_push_rr(new_list, a)) goto memory_error;
 135                         }
 136                 }
 137         }
 138
 139         ldns_rr_list_free(addr);
 140         ldns_rr_list_free(zone_cuts);
 141
 142         return new_list;
 143
 144 memory_error:
 145         if (new_list) {
 146                 ldns_rr_list_free(new_list);
 147         }
 148         if (zone_cuts) {
 149                 ldns_rr_list_free(zone_cuts);
 150         }
 151         if (addr) {
 152                 ldns_rr_list_free(addr);
 153         }
 154         return NULL;
 155 }
 156
 157 /*
 158  * Get the list of glue records in a zone
 159  * XXX: there should be a way for this to return error, other than NULL,
 160  *      since NULL is a valid return
 161  */
 162 ldns_rr_list *
 163 ldns_zone_glue_rr_list(const ldns_zone *z)
 164 {
 165         /* when do we find glue? It means we find an IP address
 166          * (AAAA/A) for a nameserver listed in the zone
 167          *
 168          * Alg used here:
 169          * first find all the zonecuts (NS records)
 170          * find all the AAAA or A records (can be done it the
 171          * above loop).
 172          *
 173          * Check if the aaaa/a list are subdomains under the
 174          * NS domains.
 175          * If yes -> glue, if no -> not glue
 176          */
 177
 178         ldns_rr_list *zone_cuts;
 179         ldns_rr_list *addr;
 180         ldns_rr_list *glue;
 181         ldns_rr *r, *ns, *a;
 182         ldns_rdf *dname_a, *ns_owner;
 183         size_t i,j;
 184
 185         zone_cuts = NULL;
 186         addr = NULL;
 187         glue = NULL;
 188
 189         /* we cannot determine glue in a 'zone' without a SOA */
 190         if (!ldns_zone_soa(z)) {
 191                 return NULL;
 192         }
 193
 194         zone_cuts = ldns_rr_list_new();
 195         if (!zone_cuts) goto memory_error;
 196         addr = ldns_rr_list_new();
 197         if (!addr) goto memory_error;
 198         glue = ldns_rr_list_new();
 199         if (!glue) goto memory_error;
 200
 201         for(i = 0; i < ldns_zone_rr_count(z); i++) {
 202                 r = ldns_rr_list_rr(ldns_zone_rrs(z), i);
 203                 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_A ||
 204                                 ldns_rr_get_type(r) == LDNS_RR_TYPE_AAAA) {
 205                         /* possibly glue */
 206                         if (!ldns_rr_list_push_rr(addr, r)) goto memory_error;
 207                         continue;
 208                 }
 209                 if (ldns_rr_get_type(r) == LDNS_RR_TYPE_NS) {
 210                         /* multiple zones will end up here -
 211                          * for now; not a problem
 212                          */
 213                         /* don't add NS records for the current zone itself */
 214                         if (ldns_rdf_compare(ldns_rr_owner(r),
 215                                                 ldns_rr_owner(ldns_zone_soa(z))) != 0) {
 216                                 if (!ldns_rr_list_push_rr(zone_cuts, r)) goto memory_error;
 217                         }
 218                         continue;
 219                 }
 220         }
 221
 222         /* will sorting make it quicker ?? */
 223         for(i = 0; i < ldns_rr_list_rr_count(zone_cuts); i++) {
 224                 ns = ldns_rr_list_rr(zone_cuts, i);
 225                 ns_owner = ldns_rr_owner(ns);
 226
 227                 for(j = 0; j < ldns_rr_list_rr_count(addr); j++) {
 228                         a = ldns_rr_list_rr(addr, j);
 229                         dname_a = ldns_rr_owner(a);
 230
 231                         if (ldns_dname_is_subdomain(dname_a, ns_owner) ||
 232                                 ldns_dname_compare(dname_a, ns_owner) == 0) {
 233                                 /* GLUE! */
 234                                 if (!ldns_rr_list_push_rr(glue, a)) goto memory_error;
 235                         }
 236                 }
 237         }
 238
 239         ldns_rr_list_free(addr);
 240         ldns_rr_list_free(zone_cuts);
 241
 242         if (ldns_rr_list_rr_count(glue) == 0) {
 243                 ldns_rr_list_free(glue);
 244                 return NULL;
 245         } else {
 246                 return glue;
 247         }
 248
 249 memory_error:
 250         if (zone_cuts) {
 251                 LDNS_FREE(zone_cuts);
 252         }
 253         if (addr) {
 254                 ldns_rr_list_free(addr);
 255         }
 256         if (glue) {
 257                 ldns_rr_list_free(glue);
 258         }
 259         return NULL;
 260 }
 261
 262 ldns_zone *
 263 ldns_zone_new(void)
 264 {
 265         ldns_zone *z;
 266
 267         z = LDNS_MALLOC(ldns_zone);
 268         if (!z) {
 269                 return NULL;
 270         }
 271
 272         z->_rrs = ldns_rr_list_new();
 273         if (!z->_rrs) {
 274                 LDNS_FREE(z);
 275                 return NULL;
 276         }
 277         ldns_zone_set_soa(z, NULL);
 278         return z;
 279 }
 280
 281 /* we regocnize:
 282  * $TTL, $ORIGIN
 283  */
 284 ldns_status
 285 ldns_zone_new_frm_fp(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl, ldns_rr_class c)
 286 {
 287         return ldns_zone_new_frm_fp_l(z, fp, origin, ttl, c, NULL);
 288 }
 289
 290 /* XXX: class is never used */
 291 ldns_status
 292 ldns_zone_new_frm_fp_l(ldns_zone **z, FILE *fp, ldns_rdf *origin, uint32_t ttl,
 293         ldns_rr_class ATTR_UNUSED(c), int *line_nr)
 294 {
 295         ldns_zone *newzone;
 296         ldns_rr *rr;
 297         uint32_t my_ttl;
 298         ldns_rdf *my_origin;
 299         ldns_rdf *my_prev;
 300         bool soa_seen = false;  /* 2 soa are an error */
 301         ldns_status s;
 302         ldns_status ret;
 303
 304         /* most cases of error are memory problems */
 305         ret = LDNS_STATUS_MEM_ERR;
 306
 307         newzone = NULL;
 308         my_origin = NULL;
 309         my_prev = NULL;
 310
 311         my_ttl    = ttl;
 312
 313         if (origin) {
 314                 my_origin = ldns_rdf_clone(origin);
 315                 if (!my_origin) goto error;
 316                 /* also set the prev */
 317                 my_prev   = ldns_rdf_clone(origin);
 318                 if (!my_prev) goto error;
 319         }
 320
 321         newzone = ldns_zone_new();
 322         if (!newzone) goto error;
 323
 324         while(!feof(fp)) {
 325                 s = ldns_rr_new_frm_fp_l(&rr, fp, &my_ttl, &my_origin, &my_prev, line_nr);
 326                 switch (s) {
 327                 case LDNS_STATUS_OK:
 328                         if (ldns_rr_get_type(rr) == LDNS_RR_TYPE_SOA) {
 329                                 if (soa_seen) {
 330                                         /* second SOA
 331                                          * just skip, maybe we want to say
 332                                          * something??? */
 333                                         ldns_rr_free(rr);
 334                                         continue;
 335                                 }
 336                                 soa_seen = true;
 337                                 ldns_zone_set_soa(newzone, rr);
 338                                 /* set origin to soa if not specified */
 339                                 if (!my_origin) {
 340                                         my_origin = ldns_rdf_clone(ldns_rr_owner(rr));
 341                                 }
 342                                 continue;
 343                         }
 344
 345                         /* a normal RR - as sofar the DNS is normal */
 346                         if (!ldns_zone_push_rr(newzone, rr)) goto error;
 347
 348                 case LDNS_STATUS_SYNTAX_EMPTY:
 349                         /* empty line was seen */
 350                 case LDNS_STATUS_SYNTAX_TTL:
 351                         /* the function set the ttl */
 352                         break;
 353                 case LDNS_STATUS_SYNTAX_ORIGIN:
 354                         /* the function set the origin */
 355                         break;
 356                 case LDNS_STATUS_SYNTAX_INCLUDE:
 357                         ret = LDNS_STATUS_SYNTAX_INCLUDE_ERR_NOTIMPL;
 358                         break;
 359                 default:
 360                         ret = s;
 361                         goto error;
 362                 }
 363         }
 364
 365         if (my_origin) {
 366                 ldns_rdf_deep_free(my_origin);
 367         }
 368         if (my_prev) {
 369                 ldns_rdf_deep_free(my_prev);
 370         }
 371         if (z) {
 372                 *z = newzone;
 373         } else {
 374                 ldns_zone_free(newzone);
 375         }
 376
 377         return LDNS_STATUS_OK;
 378
 379 error:
 380         if (my_origin) {
 381                 ldns_rdf_deep_free(my_origin);
 382         }
 383         if (my_prev) {
 384                 ldns_rdf_deep_free(my_prev);
 385         }
 386         if (newzone) {
 387                 ldns_zone_free(newzone);
 388         }
 389         return ret;
 390 }
 391
 392 void
 393 ldns_zone_sort(ldns_zone *zone)
 394 {
 395         ldns_rr_list *zrr;
 396         assert(zone != NULL);
 397
 398         zrr = ldns_zone_rrs(zone);
 399         ldns_rr_list_sort(zrr);
 400 }
 401
 402 #if 0
 403 /**
 404  * ixfr function. Work on a ldns_zone and remove and add
 405  * the rrs from the rrlist
 406  * \param[in] z the zone to work on
 407  * \param[in] del rr_list to remove from the zone
 408  * \param[in] add rr_list to add to the zone
 409  * \return Tja, wat zouden we eens returnen TODO
 410  */
 411 void
 412 ldns_zone_ixfr_del_add(ldns_zone *z, ldns_rr_list *del, ldns_rr_list *add)
 413 {
 414
 415 }
 416 #endif
 417
 418 void
 419 ldns_zone_free(ldns_zone *zone)
 420 {
 421         ldns_rr_list_free(zone->_rrs);
 422         LDNS_FREE(zone);
 423 }
 424
 425 void
 426 ldns_zone_deep_free(ldns_zone *zone)
 427 {
 428         ldns_rr_free(zone->_soa);
 429         ldns_rr_list_deep_free(zone->_rrs);
 430         LDNS_FREE(zone);
 431 }