contrib/ldns/higher.c

   1 /*
   2  * higher.c
   3  *
   4  * Specify some higher level functions that would
   5  * be usefull to would be developers
   6  *
   7  * a Net::DNS like library for C
   8  *
   9  * (c) NLnet Labs, 2004-2006
  10  *
  11  * See the file LICENSE for the license
  12  */
  13
  14 #include <ldns/config.h>
  15
  16 #include <ldns/ldns.h>
  17
  18 #ifdef HAVE_SSL
  19 #include <openssl/ssl.h>
  20 #include <openssl/sha.h>
  21 #endif /* HAVE_SSL */
  22
  23 ldns_rr_list *
  24 ldns_get_rr_list_addr_by_name(ldns_resolver *res, ldns_rdf *name, ldns_rr_class c,
  25                 uint16_t flags)
  26 {
  27         ldns_pkt *pkt;
  28         ldns_rr_list *aaaa;
  29         ldns_rr_list *a;
  30         ldns_rr_list *result = NULL;
  31         ldns_rr_list *hostsfilenames;
  32         size_t i;
  33         uint8_t ip6;
  34
  35         a = NULL;
  36         aaaa = NULL;
  37         result = NULL;
  38
  39         if (!res) {
  40                 return NULL;
  41         }
  42         if (ldns_rdf_get_type(name) != LDNS_RDF_TYPE_DNAME) {
  43                 return NULL;
  44         }
  45
  46         ip6 = ldns_resolver_ip6(res); /* we use INET_ANY here, save
  47                                          what was there */
  48
  49         ldns_resolver_set_ip6(res, LDNS_RESOLV_INETANY);
  50
  51         hostsfilenames = ldns_get_rr_list_hosts_frm_file(NULL);
  52         for (i = 0; i < ldns_rr_list_rr_count(hostsfilenames); i++) {
  53                 if (ldns_rdf_compare(name,
  54                                         ldns_rr_owner(ldns_rr_list_rr(hostsfilenames,
  55                                                         i))) == 0) {
  56                         if (!result) {
  57                                 result = ldns_rr_list_new();
  58                         }
  59                         ldns_rr_list_push_rr(result,
  60                                         ldns_rr_clone(ldns_rr_list_rr(hostsfilenames, i)));
  61                 }
  62         }
  63         ldns_rr_list_deep_free(hostsfilenames);
  64
  65         if (result) {
  66                 return result;
  67         }
  68
  69         /* add the RD flags, because we want an answer */
  70         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_AAAA, c, flags | LDNS_RD);
  71         if (pkt) {
  72                 /* extract the data we need */
  73                 aaaa = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_AAAA,
  74                         LDNS_SECTION_ANSWER);
  75                 ldns_pkt_free(pkt);
  76         }
  77
  78         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_A, c, flags | LDNS_RD);
  79         if (pkt) {
  80                 /* extract the data we need */
  81                 a = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_A, LDNS_SECTION_ANSWER);
  82                 ldns_pkt_free(pkt);
  83         }
  84         ldns_resolver_set_ip6(res, ip6);
  85
  86         if (aaaa && a) {
  87                 result = ldns_rr_list_cat_clone(aaaa, a);
  88                 ldns_rr_list_deep_free(aaaa);
  89                 ldns_rr_list_deep_free(a);
  90                 return result;
  91         }
  92
  93         if (aaaa) {
  94                 result = ldns_rr_list_clone(aaaa);
  95         }
  96
  97         if (a) {
  98                 result = ldns_rr_list_clone(a);
  99         }
 100
 101         ldns_rr_list_deep_free(aaaa);
 102         ldns_rr_list_deep_free(a);
 103         return result;
 104 }
 105
 106 ldns_rr_list *
 107 ldns_get_rr_list_name_by_addr(ldns_resolver *res, ldns_rdf *addr, ldns_rr_class c,
 108                 uint16_t flags)
 109 {
 110         ldns_pkt *pkt;
 111         ldns_rr_list *names;
 112         ldns_rdf *name;
 113
 114         names = NULL;
 115
 116         if (!res || !addr) {
 117                 return NULL;
 118         }
 119
 120         if (ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_A &&
 121                         ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_AAAA) {
 122                 return NULL;
 123         }
 124
 125         name = ldns_rdf_address_reverse(addr);
 126
 127         /* add the RD flags, because we want an answer */
 128         pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_PTR, c, flags | LDNS_RD);
 129         ldns_rdf_deep_free(name);
 130         if (pkt) {
 131                 /* extract the data we need */
 132                 names = ldns_pkt_rr_list_by_type(pkt,
 133                                 LDNS_RR_TYPE_PTR, LDNS_SECTION_ANSWER);
 134         }
 135         return names;
 136 }
 137
 138 /* read a line, put it in a buffer, parse the buffer */
 139 ldns_rr_list *
 140 ldns_get_rr_list_hosts_frm_fp(FILE *fp)
 141 {
 142         return ldns_get_rr_list_hosts_frm_fp_l(fp, NULL);
 143 }
 144
 145 ldns_rr_list *
 146 ldns_get_rr_list_hosts_frm_fp_l(FILE *fp, int *line_nr)
 147 {
 148         ssize_t i, j;
 149         size_t cnt;
 150         char *line;
 151         char *word;
 152         char *addr;
 153         char *rr_str;
 154         ldns_buffer *linebuf;
 155         ldns_rr *rr;
 156         ldns_rr_list *list;
 157         ldns_rdf *tmp;
 158         bool ip6;
 159         ldns_status parse_result;
 160
 161         line = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 162         word = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 163         addr = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 164         rr_str = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1);
 165         ip6 = false;
 166         list = ldns_rr_list_new();
 167         rr = NULL;
 168         if(!line || !word || !addr || !rr_str || !list) {
 169                 LDNS_FREE(line);
 170                 LDNS_FREE(word);
 171                 LDNS_FREE(addr);
 172                 LDNS_FREE(rr_str);
 173                 ldns_rr_list_free(list);
 174                 return NULL;
 175         }
 176
 177         for(i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr);
 178                         i > 0; i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr)) {
 179                 /* # is comment */
 180                 if (line[0] == '#') {
 181                         continue;
 182                 }
 183                 /* put it in a buffer for further processing */
 184                 linebuf = LDNS_MALLOC(ldns_buffer);
 185                 if(!linebuf) {
 186                         LDNS_FREE(line);
 187                         LDNS_FREE(word);
 188                         LDNS_FREE(addr);
 189                         LDNS_FREE(rr_str);
 190                         ldns_rr_list_deep_free(list);
 191                         return NULL;
 192                 }
 193
 194                 ldns_buffer_new_frm_data(linebuf, line, (size_t) i);
 195                 for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN);
 196                                 j > 0;
 197                                 j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN), cnt++) {
 198                         if (cnt == 0) {
 199                                 /* the address */
 200                                 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA,
 201                                                                 word))) {
 202                                         /* ip6 */
 203                                         ldns_rdf_deep_free(tmp);
 204                                         ip6 = true;
 205                                 } else {
 206                                         if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A,
 207                                                                         word))) {
 208                                                 /* ip4 */
 209                                                 ldns_rdf_deep_free(tmp);
 210                                                 ip6 = false;
 211                                         } else {
 212                                                 /* kaput */
 213                                                 break;
 214                                         }
 215                                 }
 216                                 (void)strlcpy(addr, word, LDNS_MAX_LINELEN+1);
 217                         } else {
 218                                 /* la al la la */
 219                                 if (ip6) {
 220                                         snprintf(rr_str, LDNS_MAX_LINELEN,
 221                                                 "%s IN AAAA %s", word, addr);
 222                                 } else {
 223                                         snprintf(rr_str, LDNS_MAX_LINELEN,
 224                                                 "%s IN A %s", word, addr);
 225                                 }
 226                                 parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL);
 227                                 if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) {
 228                                         ldns_rr_list_push_rr(list, ldns_rr_clone(rr));
 229                                 }
 230                                 ldns_rr_free(rr);
 231                         }
 232                 }
 233                 ldns_buffer_free(linebuf);
 234         }
 235         LDNS_FREE(line);
 236         LDNS_FREE(word);
 237         LDNS_FREE(addr);
 238         LDNS_FREE(rr_str);
 239         return list;
 240 }
 241
 242 ldns_rr_list *
 243 ldns_get_rr_list_hosts_frm_file(char *filename)
 244 {
 245         ldns_rr_list *names;
 246         FILE *fp;
 247
 248         if (!filename) {
 249                 fp = fopen(LDNS_RESOLV_HOSTS, "r");
 250
 251         } else {
 252                 fp = fopen(filename, "r");
 253         }
 254         if (!fp) {
 255                 return NULL;
 256         }
 257
 258         names = ldns_get_rr_list_hosts_frm_fp(fp);
 259         fclose(fp);
 260         return names;
 261 }
 262
 263 uint16_t
 264 ldns_getaddrinfo(ldns_resolver *res, ldns_rdf *node, ldns_rr_class c,
 265                 ldns_rr_list **ret)
 266 {
 267         ldns_rdf_type t;
 268         uint16_t names_found;
 269         ldns_resolver *r;
 270         ldns_status s;
 271
 272         t = ldns_rdf_get_type(node);
 273         names_found = 0;
 274         r = res;
 275
 276         if (res == NULL) {
 277                 /* prepare a new resolver, using /etc/resolv.conf as a guide  */
 278                 s = ldns_resolver_new_frm_file(&r, NULL);
 279                 if (s != LDNS_STATUS_OK) {
 280                         return 0;
 281                 }
 282         }
 283
 284         if (t == LDNS_RDF_TYPE_DNAME) {
 285                 /* we're asked to query for a name */
 286                 *ret = ldns_get_rr_list_addr_by_name(r, node, c, 0);
 287                 names_found = ldns_rr_list_rr_count(*ret);
 288         }
 289
 290         if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) {
 291                 /* an address */
 292                 *ret = ldns_get_rr_list_name_by_addr(r, node, c, 0);
 293                 names_found = ldns_rr_list_rr_count(*ret);
 294         }
 295
 296         if (res == NULL) {
 297                 ldns_resolver_deep_free(r);
 298         }
 299
 300         return names_found;
 301 }
 302
 303 bool
 304 ldns_nsec_type_check(ldns_rr *nsec, ldns_rr_type t)
 305 {
 306         /* does the nsec cover the t given? */
 307         /* copied from host2str.c line 465: ldns_rdf2buffer_str_nsec */
 308         uint8_t window_block_nr;
 309         uint8_t bitmap_length;
 310         uint16_t type;
 311         uint16_t pos = 0;
 312         uint16_t bit_pos;
 313         ldns_rdf *nsec_type_list = ldns_rr_rdf(nsec, 1);
 314         uint8_t *data;
 315
 316         if (nsec_type_list == NULL) {
 317                 return false;
 318         }
 319         data  = ldns_rdf_data(nsec_type_list);
 320
 321         while(pos < ldns_rdf_size(nsec_type_list)) {
 322                 window_block_nr = data[pos];
 323                 bitmap_length = data[pos + 1];
 324                 pos += 2;
 325
 326                 for (bit_pos = 0; bit_pos < (bitmap_length) * 8; bit_pos++) {
 327                         if (ldns_get_bit(&data[pos], bit_pos)) {
 328                                 type = 256 * (uint16_t) window_block_nr + bit_pos;
 329
 330                                 if ((ldns_rr_type)type == t) {
 331                                         /* we have a winner */
 332                                         return true;
 333                                 }
 334                         }
 335                 }
 336                 pos += (uint16_t) bitmap_length;
 337         }
 338         return false;
 339 }
 340
 341 void
 342 ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...)
 343 {
 344         int16_t rdf;
 345         ldns_rdf *rd;
 346         va_list va_rdf;
 347         va_start(va_rdf, rdfnum);
 348
 349         for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int))
 350         {
 351                 rd = ldns_rr_rdf(r, rdf);
 352                 if (!rd) {
 353                         continue;
 354                 } else {
 355                         ldns_rdf_print(fp, rd);
 356                         fprintf(fp, " "); /* not sure if we want to do this */
 357                 }
 358         }
 359         va_end(va_rdf);
 360 }