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 size_t i; 114 115 i = 0; 116 names = NULL; 117 118 if (!res || !addr) { 119 return NULL; 120 } 121 122 if (ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_A && 123 ldns_rdf_get_type(addr) != LDNS_RDF_TYPE_AAAA) { 124 return NULL; 125 } 126 127 name = ldns_rdf_address_reverse(addr); 128 129 /* add the RD flags, because we want an answer */ 130 pkt = ldns_resolver_query(res, name, LDNS_RR_TYPE_PTR, c, flags | LDNS_RD); 131 if (pkt) { 132 /* extract the data we need */ 133 names = ldns_pkt_rr_list_by_type(pkt, 134 LDNS_RR_TYPE_PTR, LDNS_SECTION_ANSWER); 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; 169 170 for(i = ldns_fget_token_l(fp, line, "\n", 0, line_nr); 171 i > 0; i = ldns_fget_token_l(fp, line, "\n", 0, line_nr)) { 172 /* # is comment */ 173 if (line[0] == '#') { 174 continue; 175 } 176 /* put it in a buffer for further processing */ 177 linebuf = LDNS_MALLOC(ldns_buffer); 178 179 ldns_buffer_new_frm_data(linebuf, line, (size_t) i); 180 for(cnt = 0, j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0); 181 j > 0; 182 j = ldns_bget_token(linebuf, word, LDNS_PARSE_NO_NL, 0), cnt++) { 183 if (cnt == 0) { 184 /* the address */ 185 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, 186 word))) { 187 /* ip6 */ 188 ldns_rdf_deep_free(tmp); 189 ip6 = true; 190 } else { 191 if ((tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, 192 word))) { 193 /* ip4 */ 194 ldns_rdf_deep_free(tmp); 195 ip6 = false; 196 } else { 197 /* kaput */ 198 break; 199 } 200 } 201 strlcpy(addr, word, LDNS_MAX_LINELEN+1); 202 } else { 203 /* la al la la */ 204 if (ip6) { 205 snprintf(rr_str, LDNS_MAX_LINELEN, 206 "%s IN AAAA %s", word, addr); 207 } else { 208 snprintf(rr_str, LDNS_MAX_LINELEN, 209 "%s IN A %s", word, addr); 210 } 211 parse_result = ldns_rr_new_frm_str(&rr, rr_str, 0, NULL, NULL); 212 if (parse_result == LDNS_STATUS_OK && ldns_rr_owner(rr) && ldns_rr_rd_count(rr) > 0) { 213 ldns_rr_list_push_rr(list, ldns_rr_clone(rr)); 214 } 215 ldns_rr_free(rr); 216 } 217 } 218 ldns_buffer_free(linebuf); 219 } 220 LDNS_FREE(line); 221 LDNS_FREE(word); 222 LDNS_FREE(addr); 223 LDNS_FREE(rr_str); 224 return list; 225 } 226 227 ldns_rr_list * 228 ldns_get_rr_list_hosts_frm_file(char *filename) 229 { 230 ldns_rr_list *names; 231 FILE *fp; 232 233 if (!filename) { 234 fp = fopen(LDNS_RESOLV_HOSTS, "r"); 235 236 } else { 237 fp = fopen(filename, "r"); 238 } 239 if (!fp) { 240 return NULL; 241 } 242 243 names = ldns_get_rr_list_hosts_frm_fp(fp); 244 fclose(fp); 245 return names; 246 } 247 248 uint16_t 249 ldns_getaddrinfo(ldns_resolver *res, ldns_rdf *node, ldns_rr_class c, 250 ldns_rr_list **ret) 251 { 252 ldns_rdf_type t; 253 uint16_t names_found; 254 ldns_resolver *r; 255 ldns_status s; 256 257 t = ldns_rdf_get_type(node); 258 names_found = 0; 259 r = res; 260 261 if (res == NULL) { 262 /* prepare a new resolver, using /etc/resolv.conf as a guide */ 263 s = ldns_resolver_new_frm_file(&r, NULL); 264 if (s != LDNS_STATUS_OK) { 265 return 0; 266 } 267 } 268 269 if (t == LDNS_RDF_TYPE_DNAME) { 270 /* we're asked to query for a name */ 271 *ret = ldns_get_rr_list_addr_by_name(r, node, c, 0); 272 names_found = ldns_rr_list_rr_count(*ret); 273 } 274 275 if (t == LDNS_RDF_TYPE_A || t == LDNS_RDF_TYPE_AAAA) { 276 /* an address */ 277 *ret = ldns_get_rr_list_name_by_addr(r, node, c, 0); 278 names_found = ldns_rr_list_rr_count(*ret); 279 } 280 281 if (res == NULL) { 282 ldns_resolver_deep_free(r); 283 } 284 285 return names_found; 286 } 287 288 bool 289 ldns_nsec_type_check(ldns_rr *nsec, ldns_rr_type t) 290 { 291 /* does the nsec cover the t given? */ 292 /* copied from host2str.c line 465: ldns_rdf2buffer_str_nsec */ 293 uint8_t window_block_nr; 294 uint8_t bitmap_length; 295 uint16_t type; 296 uint16_t pos = 0; 297 uint16_t bit_pos; 298 ldns_rdf *nsec_type_list = ldns_rr_rdf(nsec, 1); 299 uint8_t *data = ldns_rdf_data(nsec_type_list); 300 301 while(pos < ldns_rdf_size(nsec_type_list)) { 302 window_block_nr = data[pos]; 303 bitmap_length = data[pos + 1]; 304 pos += 2; 305 306 for (bit_pos = 0; bit_pos < (bitmap_length) * 8; bit_pos++) { 307 if (ldns_get_bit(&data[pos], bit_pos)) { 308 type = 256 * (uint16_t) window_block_nr + bit_pos; 309 310 if ((ldns_rr_type)type == t) { 311 /* we have a winner */ 312 return true; 313 } 314 } 315 } 316 pos += (uint16_t) bitmap_length; 317 } 318 return false; 319 } 320 321 void 322 ldns_print_rr_rdf(FILE *fp, ldns_rr *r, int rdfnum, ...) 323 { 324 int16_t rdf; 325 ldns_rdf *rd; 326 va_list va_rdf; 327 va_start(va_rdf, rdfnum); 328 329 for (rdf = (int16_t)rdfnum; rdf != -1; rdf = (int16_t)va_arg(va_rdf, int)) 330 { 331 rd = ldns_rr_rdf(r, rdf); 332 if (!rd) { 333 continue; 334 } else { 335 ldns_rdf_print(fp, rd); 336 fprintf(fp, " "); /* not sure if we want to do this */ 337 } 338 } 339 va_end(va_rdf); 340 } 341