1 /* 2 * higher.c 3 * 4 * Specify some higher level functions that would 5 * be useful 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, const ldns_rdf *name, 25 ldns_rr_class c, 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, const ldns_rdf *addr, 108 ldns_rr_class c, 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 ldns_pkt_free(pkt); 135 } 136 return names; 137 } 138 139 /* read a line, put it in a buffer, parse the buffer */ 140 ldns_rr_list * 141 ldns_get_rr_list_hosts_frm_fp(FILE *fp) 142 { 143 return ldns_get_rr_list_hosts_frm_fp_l(fp, NULL); 144 } 145 146 ldns_rr_list * 147 ldns_get_rr_list_hosts_frm_fp_l(FILE *fp, int *line_nr) 148 { 149 ssize_t i, j; 150 size_t cnt; 151 char *line; 152 char *word; 153 char *addr; 154 char *rr_str; 155 ldns_buffer *linebuf; 156 ldns_rr *rr; 157 ldns_rr_list *list; 158 ldns_rdf *tmp; 159 bool ip6; 160 ldns_status parse_result; 161 162 line = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 163 word = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 164 addr = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 165 rr_str = LDNS_XMALLOC(char, LDNS_MAX_LINELEN + 1); 166 ip6 = false; 167 list = ldns_rr_list_new(); 168 rr = NULL; 169 if(!line || !word || !addr || !rr_str || !list) { 170 LDNS_FREE(line); 171 LDNS_FREE(word); 172 LDNS_FREE(addr); 173 LDNS_FREE(rr_str); 174 ldns_rr_list_free(list); 175 return NULL; 176 } 177 178 for(i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr); 179 i > 0; i = ldns_fget_token_l(fp, line, "\n", LDNS_MAX_LINELEN, line_nr)) { 180 /* # is comment */ 181 if (line[0] == '#') { 182 continue; 183 } 184 /* put it in a buffer for further processing */ 185 linebuf = LDNS_MALLOC(ldns_buffer); 186 if(!linebuf) { 187 LDNS_FREE(line); 188 LDNS_FREE(word); 189 LDNS_FREE(addr); 190 LDNS_FREE(rr_str); 191 ldns_rr_list_deep_free(list); 192 return NULL; 193 } 194 195 ldns_buffer_new_frm_data(linebuf, line, (size_t) i); 196 for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN); 197 j > 0; 198 j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, LDNS_MAX_LINELEN), cnt++) { 199 if (cnt == 0) { 200 /* the address */ 201 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, 202 word))) { 203 /* ip6 */ 204 ldns_rdf_deep_free(tmp); 205 ip6 = true; 206 } else { 207 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, 208 word))) { 209 /* ip4 */ 210 ldns_rdf_deep_free(tmp); 211 ip6 = false; 212 } else { 213 /* kaput */ 214 break; 215 } 216 } 217 (void)strlcpy(addr, word, LDNS_MAX_LINELEN+1); 218 } else { 219 /* Stop parsing line when a comment begins. */ 220 if (word[0] == '#') 221 break; 222 /* la al la la */ 223 if (ip6) { 224 snprintf(rr_str, LDNS_MAX_LINELEN, 225 "%s IN AAAA %s", word, addr); 226 } else { 227 snprintf(rr_str, LDNS_MAX_LINELEN, 228 "%s IN A %s", word, addr); 229 } 230 parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL); 231 if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) { 232 ldns_rr_list_push_rr(list, ldns_rr_clone(rr)); 233 ldns_rr_free(rr); 234 } 235 } 236 } 237 ldns_buffer_free(linebuf); 238 } 239 LDNS_FREE(line); 240 LDNS_FREE(word); 241 LDNS_FREE(addr); 242 LDNS_FREE(rr_str); 243 return list; 244 } 245 246 ldns_rr_list * 247 ldns_get_rr_list_hosts_frm_file(char *filename) 248 { 249 ldns_rr_list *names; 250 FILE *fp; 251 252 if (!filename) { 253 fp = fopen(LDNS_RESOLV_HOSTS, "r"); 254 255 } else { 256 fp = fopen(filename, "r"); 257 } 258 if (!fp) { 259 return NULL; 260 } 261 262 names = ldns_get_rr_list_hosts_frm_fp(fp); 263 fclose(fp); 264 return names; 265 } 266 267 uint16_t 268 ldns_getaddrinfo(ldns_resolver *res, const ldns_rdf *node, 269 ldns_rr_class c, ldns_rr_list **ret) 270 { 271 ldns_rdf_type t; 272 uint16_t names_found; 273 ldns_resolver *r; 274 ldns_status s; 275 276 t = ldns_rdf_get_type(node); 277 names_found = 0; 278 r = res; 279 280 if (res == NULL) { 281 /* prepare a new resolver, using /etc/resolv.conf as a guide */ 282 s = ldns_resolver_new_frm_file(&r, NULL); 283 if (s != LDNS_STATUS_OK) { 284 return 0; 285 } 286 } 287 288 if (t == LDNS_RDF_TYPE_DNAME) { 289 /* we're asked to query for a name */ 290 *ret = ldns_get_rr_list_addr_by_name(r, node, c, 0); 291 names_found = ldns_rr_list_rr_count(*ret); 292 } 293 294 if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) { 295 /* an address */ 296 *ret = ldns_get_rr_list_name_by_addr(r, node, c, 0); 297 names_found = ldns_rr_list_rr_count(*ret); 298 } 299 300 if (res == NULL) { 301 ldns_resolver_deep_free(r); 302 } 303 304 return names_found; 305 } 306 307 bool 308 ldns_nsec_type_check(const ldns_rr *nsec, ldns_rr_type t) 309 { 310 switch (ldns_rr_get_type(nsec)) { 311 case LDNS_RR_TYPE_NSEC : if (ldns_rr_rd_count(nsec) < 2) { 312 return false; 313 } 314 return ldns_nsec_bitmap_covers_type( 315 ldns_rr_rdf(nsec, 1), t); 316 317 case LDNS_RR_TYPE_NSEC3 : if (ldns_rr_rd_count(nsec) < 6) { 318 return false; 319 } 320 return ldns_nsec_bitmap_covers_type( 321 ldns_rr_rdf(nsec, 5), t); 322 323 default : return false; 324 } 325 } 326 327 void 328 ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...) 329 { 330 int16_t rdf; 331 ldns_rdf *rd; 332 va_list va_rdf; 333 va_start(va_rdf, rdfnum); 334 335 for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int)) 336 { 337 rd = ldns_rr_rdf(r, rdf); 338 if (!rd) { 339 continue; 340 } else { 341 ldns_rdf_print(fp, rd); 342 fprintf(fp, " "); /* not sure if we want to do this */ 343 } 344 } 345 va_end(va_rdf); 346 } 347 348