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 if (pkt) { 130 /* extract the data we need */ 131 names = ldns_pkt_rr_list_by_type(pkt, 132 LDNS_RR_TYPE_PTR, LDNS_SECTION_ANSWER); 133 } 134 return names; 135 } 136 137 /* read a line, put it in a buffer, parse the buffer */ 138 ldns_rr_list * 139 ldns_get_rr_list_hosts_frm_fp(FILE *fp) 140 { 141 return ldns_get_rr_list_hosts_frm_fp_l(fp, NULL); 142 } 143 144 ldns_rr_list * 145 ldns_get_rr_list_hosts_frm_fp_l(FILE *fp, int *line_nr) 146 { 147 ssize_t i, j; 148 size_t cnt; 149 char *line; 150 char *word; 151 char *addr; 152 char *rr_str; 153 ldns_buffer *linebuf; 154 ldns_rr *rr; 155 ldns_rr_list *list; 156 ldns_rdf *tmp; 157 bool ip6; 158 ldns_status parse_result; 159 160 line = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 161 word = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 162 addr = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 163 rr_str = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 164 ip6 = false; 165 list = ldns_rr_list_new(); 166 rr = NULL; 167 if(!line || !word || !addr || !rr_str || !list) { 168 LDNS_FREE(line); 169 LDNS_FREE(word); 170 LDNS_FREE(addr); 171 LDNS_FREE(rr_str); 172 ldns_rr_list_free(list); 173 return NULL; 174 } 175 176 for(i = ldns_fget_token_l(fp, line, "\n", 0, line_nr); 177 i > 0; i = ldns_fget_token_l(fp, line, "\n", 0, line_nr)) { 178 /* # is comment */ 179 if (line[0] == '#') { 180 continue; 181 } 182 /* put it in a buffer for further processing */ 183 linebuf = LDNS_MALLOC(ldns_buffer); 184 if(!linebuf) { 185 LDNS_FREE(line); 186 LDNS_FREE(word); 187 LDNS_FREE(addr); 188 LDNS_FREE(rr_str); 189 ldns_rr_list_deep_free(list); 190 return NULL; 191 } 192 193 ldns_buffer_new_frm_data(linebuf, line, (size_t) i); 194 for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0); 195 j > 0; 196 j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0), cnt++) { 197 if (cnt == 0) { 198 /* the address */ 199 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, 200 word))) { 201 /* ip6 */ 202 ldns_rdf_deep_free(tmp); 203 ip6 = true; 204 } else { 205 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, 206 word))) { 207 /* ip4 */ 208 ldns_rdf_deep_free(tmp); 209 ip6 = false; 210 } else { 211 /* kaput */ 212 break; 213 } 214 } 215 strlcpy(addr, word, LDNS_MAX_LINELEN+1); 216 } else { 217 /* la al la la */ 218 if (ip6) { 219 snprintf(rr_str, LDNS_MAX_LINELEN, 220 "%s IN AAAA %s", word, addr); 221 } else { 222 snprintf(rr_str, LDNS_MAX_LINELEN, 223 "%s IN A %s", word, addr); 224 } 225 parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL); 226 if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) { 227 ldns_rr_list_push_rr(list, ldns_rr_clone(rr)); 228 } 229 ldns_rr_free(rr); 230 } 231 } 232 ldns_buffer_free(linebuf); 233 } 234 LDNS_FREE(line); 235 LDNS_FREE(word); 236 LDNS_FREE(addr); 237 LDNS_FREE(rr_str); 238 return list; 239 } 240 241 ldns_rr_list * 242 ldns_get_rr_list_hosts_frm_file(char *filename) 243 { 244 ldns_rr_list *names; 245 FILE *fp; 246 247 if (!filename) { 248 fp = fopen(LDNS_RESOLV_HOSTS, "r"); 249 250 } else { 251 fp = fopen(filename, "r"); 252 } 253 if (!fp) { 254 return NULL; 255 } 256 257 names = ldns_get_rr_list_hosts_frm_fp(fp); 258 fclose(fp); 259 return names; 260 } 261 262 uint16_t 263 ldns_getaddrinfo(ldns_resolver *res, ldns_rdf *node, ldns_rr_class c, 264 ldns_rr_list **ret) 265 { 266 ldns_rdf_type t; 267 uint16_t names_found; 268 ldns_resolver *r; 269 ldns_status s; 270 271 t = ldns_rdf_get_type(node); 272 names_found = 0; 273 r = res; 274 275 if (res == NULL) { 276 /* prepare a new resolver, using /etc/resolv.conf as a guide */ 277 s = ldns_resolver_new_frm_file(&r, NULL); 278 if (s != LDNS_STATUS_OK) { 279 return 0; 280 } 281 } 282 283 if (t == LDNS_RDF_TYPE_DNAME) { 284 /* we're asked to query for a name */ 285 *ret = ldns_get_rr_list_addr_by_name(r, node, c, 0); 286 names_found = ldns_rr_list_rr_count(*ret); 287 } 288 289 if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) { 290 /* an address */ 291 *ret = ldns_get_rr_list_name_by_addr(r, node, c, 0); 292 names_found = ldns_rr_list_rr_count(*ret); 293 } 294 295 if (res == NULL) { 296 ldns_resolver_deep_free(r); 297 } 298 299 return names_found; 300 } 301 302 bool 303 ldns_nsec_type_check(ldns_rr *nsec, ldns_rr_type t) 304 { 305 /* does the nsec cover the t given? */ 306 /* copied from host2str.c line 465: ldns_rdf2buffer_str_nsec */ 307 uint8_t window_block_nr; 308 uint8_t bitmap_length; 309 uint16_t type; 310 uint16_t pos = 0; 311 uint16_t bit_pos; 312 ldns_rdf *nsec_type_list = ldns_rr_rdf(nsec, 1); 313 uint8_t *data = ldns_rdf_data(nsec_type_list); 314 315 while(pos < ldns_rdf_size(nsec_type_list)) { 316 window_block_nr = data[pos]; 317 bitmap_length = data[pos + 1]; 318 pos += 2; 319 320 for (bit_pos = 0; bit_pos < (bitmap_length) * 8; bit_pos++) { 321 if (ldns_get_bit(&data[pos], bit_pos)) { 322 type = 256 * (uint16_t) window_block_nr + bit_pos; 323 324 if ((ldns_rr_type)type == t) { 325 /* we have a winner */ 326 return true; 327 } 328 } 329 } 330 pos += (uint16_t) bitmap_length; 331 } 332 return false; 333 } 334 335 void 336 ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...) 337 { 338 int16_t rdf; 339 ldns_rdf *rd; 340 va_list va_rdf; 341 va_start(va_rdf, rdfnum); 342 343 for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int)) 344 { 345 rd = ldns_rr_rdf(r, rdf); 346 if (!rd) { 347 continue; 348 } else { 349 ldns_rdf_print(fp, rd); 350 fprintf(fp, " "); /* not sure if we want to do this */ 351 } 352 } 353 va_end(va_rdf); 354 } 355