| File: | src/lib/libc/asr/gethostnamadr_async.c |
| Warning: | line 324, column 8 Although the value stored to 'r' is used in the enclosing expression, the value is never actually read from 'r' |
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| 1 | /* $OpenBSD: gethostnamadr_async.c,v 1.49 2023/11/22 13:19:31 florian Exp $ */ |
| 2 | /* |
| 3 | * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> |
| 4 | * |
| 5 | * Permission to use, copy, modify, and distribute this software for any |
| 6 | * purpose with or without fee is hereby granted, provided that the above |
| 7 | * copyright notice and this permission notice appear in all copies. |
| 8 | * |
| 9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 12 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 14 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 15 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 16 | */ |
| 17 | |
| 18 | #include <sys/types.h> |
| 19 | #include <sys/socket.h> |
| 20 | #include <netinet/in.h> |
| 21 | #include <arpa/inet.h> |
| 22 | #include <arpa/nameser.h> |
| 23 | #include <netdb.h> |
| 24 | |
| 25 | #include <asr.h> |
| 26 | #include <ctype.h> |
| 27 | #include <errno(*__errno()).h> |
| 28 | #include <resolv.h> /* for res_hnok */ |
| 29 | #include <stdlib.h> |
| 30 | #include <string.h> |
| 31 | #include <unistd.h> |
| 32 | #include <limits.h> |
| 33 | |
| 34 | #include "asr_private.h" |
| 35 | |
| 36 | #define MAXALIASES35 35 |
| 37 | #define MAXADDRS35 35 |
| 38 | |
| 39 | struct hostent_ext { |
| 40 | struct hostent h; |
| 41 | char *aliases[MAXALIASES35 + 1]; |
| 42 | char *addrs[MAXADDRS35 + 1]; |
| 43 | char *end; |
| 44 | char *pos; |
| 45 | }; |
| 46 | |
| 47 | struct netent_ext { |
| 48 | struct netent n; |
| 49 | char *aliases[MAXALIASES35 + 1]; |
| 50 | char *end; |
| 51 | char *pos; |
| 52 | }; |
| 53 | |
| 54 | static int gethostnamadr_async_run(struct asr_query *, struct asr_result *); |
| 55 | static struct hostent_ext *hostent_alloc(int); |
| 56 | static int hostent_set_cname(struct hostent_ext *, const char *, int); |
| 57 | static int hostent_add_alias(struct hostent_ext *, const char *, int); |
| 58 | static int hostent_add_addr(struct hostent_ext *, const void *, size_t); |
| 59 | static struct hostent_ext *hostent_from_addr(int, const char *, const char *); |
| 60 | static struct hostent_ext *hostent_file_match(FILE *, int, int, const char *, |
| 61 | int); |
| 62 | static struct hostent_ext *hostent_from_packet(int, int, char *, size_t); |
| 63 | static void netent_from_hostent(struct asr_result *ar); |
| 64 | |
| 65 | struct asr_query * |
| 66 | gethostbyname_async(const char *name, void *asr) |
| 67 | { |
| 68 | return gethostbyname2_async(name, AF_INET2, asr); |
| 69 | } |
| 70 | DEF_WEAK(gethostbyname_async)__asm__(".weak " "gethostbyname_async" " ; " "gethostbyname_async" " = " "_libc_gethostbyname_async"); |
| 71 | |
| 72 | struct asr_query * |
| 73 | gethostbyname2_async(const char *name, int af, void *asr) |
| 74 | { |
| 75 | struct asr_ctx *ac; |
| 76 | struct asr_query *as; |
| 77 | |
| 78 | /* the original segfaults */ |
| 79 | if (name == NULL((void *)0)) { |
| 80 | errno(*__errno()) = EINVAL22; |
| 81 | return (NULL((void *)0)); |
| 82 | } |
| 83 | |
| 84 | ac = _asr_use_resolver(asr); |
| 85 | if ((as = _asr_async_new(ac, ASR_GETHOSTBYNAME)) == NULL((void *)0)) |
| 86 | goto abort; /* errno set */ |
| 87 | as->as_run = gethostnamadr_async_run; |
| 88 | |
| 89 | as->as.hostnamadr.family = af; |
| 90 | if (af == AF_INET2) |
| 91 | as->as.hostnamadr.addrlen = INADDRSZ4; |
| 92 | else if (af == AF_INET624) |
| 93 | as->as.hostnamadr.addrlen = IN6ADDRSZ16; |
| 94 | as->as.hostnamadr.name = strdup(name); |
| 95 | if (as->as.hostnamadr.name == NULL((void *)0)) |
| 96 | goto abort; /* errno set */ |
| 97 | |
| 98 | _asr_ctx_unref(ac); |
| 99 | return (as); |
| 100 | |
| 101 | abort: |
| 102 | if (as) |
| 103 | _asr_async_free(as); |
| 104 | _asr_ctx_unref(ac); |
| 105 | return (NULL((void *)0)); |
| 106 | } |
| 107 | DEF_WEAK(gethostbyname2_async)__asm__(".weak " "gethostbyname2_async" " ; " "gethostbyname2_async" " = " "_libc_gethostbyname2_async"); |
| 108 | |
| 109 | struct asr_query * |
| 110 | gethostbyaddr_async(const void *addr, socklen_t len, int af, void *asr) |
| 111 | { |
| 112 | struct asr_ctx *ac; |
| 113 | struct asr_query *as; |
| 114 | |
| 115 | ac = _asr_use_resolver(asr); |
| 116 | as = _gethostbyaddr_async_ctx(addr, len, af, ac); |
| 117 | _asr_ctx_unref(ac); |
| 118 | |
| 119 | return (as); |
| 120 | } |
| 121 | DEF_WEAK(gethostbyaddr_async)__asm__(".weak " "gethostbyaddr_async" " ; " "gethostbyaddr_async" " = " "_libc_gethostbyaddr_async"); |
| 122 | |
| 123 | struct asr_query * |
| 124 | _gethostbyaddr_async_ctx(const void *addr, socklen_t len, int af, |
| 125 | struct asr_ctx *ac) |
| 126 | { |
| 127 | struct asr_query *as; |
| 128 | |
| 129 | if ((as = _asr_async_new(ac, ASR_GETHOSTBYADDR)) == NULL((void *)0)) |
| 130 | goto abort; /* errno set */ |
| 131 | as->as_run = gethostnamadr_async_run; |
| 132 | |
| 133 | as->as.hostnamadr.family = af; |
| 134 | as->as.hostnamadr.addrlen = len; |
| 135 | if (len > 0) |
| 136 | memmove(as->as.hostnamadr.addr, addr, (len > 16) ? 16 : len); |
| 137 | |
| 138 | return (as); |
| 139 | |
| 140 | abort: |
| 141 | if (as) |
| 142 | _asr_async_free(as); |
| 143 | return (NULL((void *)0)); |
| 144 | } |
| 145 | |
| 146 | static int |
| 147 | gethostnamadr_async_run(struct asr_query *as, struct asr_result *ar) |
| 148 | { |
| 149 | struct hostent_ext *h; |
| 150 | int r, type, saved_errno; |
| 151 | FILE *f; |
| 152 | char name[MAXDNAME1025], *data, addr[16], *c; |
| 153 | |
| 154 | next: |
| 155 | switch (as->as_state) { |
| 156 | |
| 157 | case ASR_STATE_INIT: |
| 158 | |
| 159 | if (as->as.hostnamadr.family != AF_INET2 && |
| 160 | as->as.hostnamadr.family != AF_INET624) { |
| 161 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 162 | ar->ar_errno = EAFNOSUPPORT47; |
| 163 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 164 | break; |
| 165 | } |
| 166 | |
| 167 | if ((as->as.hostnamadr.family == AF_INET2 && |
| 168 | as->as.hostnamadr.addrlen != INADDRSZ4) || |
| 169 | (as->as.hostnamadr.family == AF_INET624 && |
| 170 | as->as.hostnamadr.addrlen != IN6ADDRSZ16)) { |
| 171 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 172 | ar->ar_errno = EINVAL22; |
| 173 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 174 | break; |
| 175 | } |
| 176 | |
| 177 | if (as->as_type == ASR_GETHOSTBYNAME) { |
| 178 | |
| 179 | if (as->as.hostnamadr.name[0] == '\0') { |
| 180 | ar->ar_h_errno = NO_DATA4; |
| 181 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 182 | break; |
| 183 | } |
| 184 | |
| 185 | /* Name might be an IP address string */ |
| 186 | for (c = as->as.hostnamadr.name; *c; c++) |
| 187 | if (!isdigit((unsigned char)*c) && |
| 188 | *c != '.' && *c != ':') |
| 189 | break; |
| 190 | if (*c == 0 && |
| 191 | inet_pton(as->as.hostnamadr.family, |
| 192 | as->as.hostnamadr.name, addr) == 1) { |
| 193 | h = hostent_from_addr(as->as.hostnamadr.family, |
| 194 | as->as.hostnamadr.name, addr); |
| 195 | if (h == NULL((void *)0)) { |
| 196 | ar->ar_errno = errno(*__errno()); |
| 197 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 198 | } |
| 199 | else { |
| 200 | ar->ar_hostent = &h->h; |
| 201 | ar->ar_h_errno = NETDB_SUCCESS0; |
| 202 | } |
| 203 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 204 | break; |
| 205 | } |
| 206 | |
| 207 | if (!hnok_lenient(as->as.hostnamadr.name)) { |
| 208 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 209 | ar->ar_errno = EINVAL22; |
| 210 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 211 | break; |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * If hostname is "localhost" or falls within the |
| 216 | * ".localhost." domain, use local address. |
| 217 | * RFC 6761, 6.3: |
| 218 | * 3. Name resolution APIs and libraries SHOULD |
| 219 | * recognize localhost names as special and SHOULD |
| 220 | * always return the IP loopback address for address |
| 221 | * queries and negative responses for all other query |
| 222 | * types. Name resolution APIs SHOULD NOT send queries |
| 223 | * for localhost names to their configured caching DNS |
| 224 | * server(s). |
| 225 | */ |
| 226 | |
| 227 | if (_asr_is_localhost(as->as.hostnamadr.name)) { |
| 228 | inet_pton(as->as.hostnamadr.family, |
| 229 | as->as.hostnamadr.family == AF_INET2 ? |
| 230 | "127.0.0.1" : "::1", addr); |
| 231 | h = hostent_from_addr(as->as.hostnamadr.family, |
| 232 | as->as.hostnamadr.name, addr); |
| 233 | if (h == NULL((void *)0)) { |
| 234 | ar->ar_errno = errno(*__errno()); |
| 235 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 236 | } |
| 237 | else { |
| 238 | ar->ar_hostent = &h->h; |
| 239 | ar->ar_h_errno = NETDB_SUCCESS0; |
| 240 | } |
| 241 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 242 | break; |
| 243 | } |
| 244 | } |
| 245 | async_set_state(as, ASR_STATE_NEXT_DB)do { ; (as)->as_state = (ASR_STATE_NEXT_DB); } while (0); |
| 246 | break; |
| 247 | |
| 248 | case ASR_STATE_NEXT_DB: |
| 249 | |
| 250 | if (_asr_iter_db(as) == -1) { |
| 251 | async_set_state(as, ASR_STATE_NOT_FOUND)do { ; (as)->as_state = (ASR_STATE_NOT_FOUND); } while (0); |
| 252 | break; |
| 253 | } |
| 254 | |
| 255 | switch (AS_DB(as)((as)->as_ctx->ac_db[(as)->as_db_idx - 1])) { |
| 256 | |
| 257 | case ASR_DB_DNS'b': |
| 258 | |
| 259 | /* Create a subquery to do the DNS lookup */ |
| 260 | |
| 261 | if (as->as_type == ASR_GETHOSTBYNAME) { |
| 262 | type = (as->as.hostnamadr.family == AF_INET2) ? |
| 263 | T_A1 : T_AAAA28; |
| 264 | as->as_subq = _res_search_async_ctx( |
| 265 | as->as.hostnamadr.name, |
| 266 | C_IN1, type, as->as_ctx); |
| 267 | } else { |
| 268 | _asr_addr_as_fqdn(as->as.hostnamadr.addr, |
| 269 | as->as.hostnamadr.family, |
| 270 | name, sizeof(name)); |
| 271 | as->as_subq = _res_query_async_ctx( |
| 272 | name, C_IN1, T_PTR12, as->as_ctx); |
| 273 | } |
| 274 | |
| 275 | if (as->as_subq == NULL((void *)0)) { |
| 276 | ar->ar_errno = errno(*__errno()); |
| 277 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 278 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 279 | break; |
| 280 | } |
| 281 | |
| 282 | async_set_state(as, ASR_STATE_SUBQUERY)do { ; (as)->as_state = (ASR_STATE_SUBQUERY); } while (0); |
| 283 | break; |
| 284 | |
| 285 | case ASR_DB_FILE'f': |
| 286 | |
| 287 | /* Try to find a match in the host file */ |
| 288 | |
| 289 | if ((f = fopen(_PATH_HOSTS"/etc/hosts", "re")) == NULL((void *)0)) |
| 290 | break; |
| 291 | |
| 292 | if (as->as_type == ASR_GETHOSTBYNAME) |
| 293 | data = as->as.hostnamadr.name; |
| 294 | else |
| 295 | data = as->as.hostnamadr.addr; |
| 296 | |
| 297 | h = hostent_file_match(f, as->as_type, |
| 298 | as->as.hostnamadr.family, data, |
| 299 | as->as.hostnamadr.addrlen); |
| 300 | saved_errno = errno(*__errno()); |
| 301 | fclose(f); |
| 302 | errno(*__errno()) = saved_errno; |
| 303 | |
| 304 | if (h == NULL((void *)0)) { |
| 305 | if (errno(*__errno())) { |
| 306 | ar->ar_errno = errno(*__errno()); |
| 307 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 308 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 309 | } |
| 310 | /* otherwise not found */ |
| 311 | break; |
| 312 | } |
| 313 | ar->ar_hostent = &h->h; |
| 314 | ar->ar_h_errno = NETDB_SUCCESS0; |
| 315 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 316 | break; |
| 317 | } |
| 318 | break; |
| 319 | |
| 320 | case ASR_STATE_SUBQUERY: |
| 321 | |
| 322 | /* Run the DNS subquery. */ |
| 323 | |
| 324 | if ((r = asr_run(as->as_subq, ar)) == ASYNC_COND0) |
Although the value stored to 'r' is used in the enclosing expression, the value is never actually read from 'r' | |
| 325 | return (ASYNC_COND0); |
| 326 | |
| 327 | /* Done. */ |
| 328 | as->as_subq = NULL((void *)0); |
| 329 | |
| 330 | /* |
| 331 | * We either got no packet or a packet without an answer. |
| 332 | * Saveguard the h_errno and use the next DB. |
| 333 | */ |
| 334 | if (ar->ar_count == 0) { |
| 335 | free(ar->ar_data); |
| 336 | as->as.hostnamadr.subq_h_errno = ar->ar_h_errno; |
| 337 | async_set_state(as, ASR_STATE_NEXT_DB)do { ; (as)->as_state = (ASR_STATE_NEXT_DB); } while (0); |
| 338 | break; |
| 339 | } |
| 340 | |
| 341 | /* Read the hostent from the packet. */ |
| 342 | |
| 343 | h = hostent_from_packet(as->as_type, |
| 344 | as->as.hostnamadr.family, ar->ar_data, ar->ar_datalen); |
| 345 | free(ar->ar_data); |
| 346 | if (h == NULL((void *)0)) { |
| 347 | ar->ar_errno = errno(*__errno()); |
| 348 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 349 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 350 | break; |
| 351 | } |
| 352 | |
| 353 | if (as->as_type == ASR_GETHOSTBYADDR) { |
| 354 | if (hostent_add_addr(h, as->as.hostnamadr.addr, |
| 355 | as->as.hostnamadr.addrlen) == -1) { |
| 356 | free(h); |
| 357 | ar->ar_errno = errno(*__errno()); |
| 358 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 359 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 360 | break; |
| 361 | } |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * No valid hostname or address found in the dns packet. |
| 366 | * Ignore it. |
| 367 | */ |
| 368 | if ((as->as_type == ASR_GETHOSTBYNAME && |
| 369 | h->h.h_addr_list[0] == NULL((void *)0)) || |
| 370 | h->h.h_name == NULL((void *)0)) { |
| 371 | free(h); |
| 372 | async_set_state(as, ASR_STATE_NEXT_DB)do { ; (as)->as_state = (ASR_STATE_NEXT_DB); } while (0); |
| 373 | break; |
| 374 | } |
| 375 | |
| 376 | ar->ar_hostent = &h->h; |
| 377 | ar->ar_h_errno = NETDB_SUCCESS0; |
| 378 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 379 | break; |
| 380 | |
| 381 | case ASR_STATE_NOT_FOUND: |
| 382 | ar->ar_errno = 0; |
| 383 | if (as->as.hostnamadr.subq_h_errno) |
| 384 | ar->ar_h_errno = as->as.hostnamadr.subq_h_errno; |
| 385 | else |
| 386 | ar->ar_h_errno = HOST_NOT_FOUND1; |
| 387 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 388 | break; |
| 389 | |
| 390 | case ASR_STATE_HALT: |
| 391 | if (ar->ar_h_errno == NETDB_SUCCESS0 && |
| 392 | as->as_flags & ASYNC_GETNET0x00001000) |
| 393 | netent_from_hostent(ar); |
| 394 | if (ar->ar_h_errno) { |
| 395 | ar->ar_hostent = NULL((void *)0); |
| 396 | ar->ar_netent = NULL((void *)0); |
| 397 | } else |
| 398 | ar->ar_errno = 0; |
| 399 | return (ASYNC_DONE1); |
| 400 | |
| 401 | default: |
| 402 | ar->ar_errno = EOPNOTSUPP45; |
| 403 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 404 | ar->ar_gai_errno = EAI_SYSTEM-11; |
| 405 | async_set_state(as, ASR_STATE_HALT)do { ; (as)->as_state = (ASR_STATE_HALT); } while (0); |
| 406 | break; |
| 407 | } |
| 408 | goto next; |
| 409 | } |
| 410 | |
| 411 | /* |
| 412 | * Create a hostent from a numeric address string. |
| 413 | */ |
| 414 | static struct hostent_ext * |
| 415 | hostent_from_addr(int family, const char *name, const char *addr) |
| 416 | { |
| 417 | struct hostent_ext *h; |
| 418 | |
| 419 | if ((h = hostent_alloc(family)) == NULL((void *)0)) |
| 420 | return (NULL((void *)0)); |
| 421 | if (hostent_set_cname(h, name, 0) == -1) |
| 422 | goto fail; |
| 423 | if (hostent_add_addr(h, addr, h->h.h_length) == -1) |
| 424 | goto fail; |
| 425 | return (h); |
| 426 | fail: |
| 427 | free(h); |
| 428 | return (NULL((void *)0)); |
| 429 | } |
| 430 | |
| 431 | /* |
| 432 | * Lookup the first matching entry in the hostfile, either by address or by |
| 433 | * name depending on reqtype, and build a hostent from the line. |
| 434 | */ |
| 435 | static struct hostent_ext * |
| 436 | hostent_file_match(FILE *f, int reqtype, int family, const char *data, |
| 437 | int datalen) |
| 438 | { |
| 439 | char *tokens[MAXTOKEN10], addr[16], buf[BUFSIZ1024 + 1]; |
| 440 | struct hostent_ext *h; |
| 441 | int n, i; |
| 442 | |
| 443 | for (;;) { |
| 444 | n = _asr_parse_namedb_line(f, tokens, MAXTOKEN10, buf, sizeof(buf)); |
| 445 | if (n == -1) { |
| 446 | errno(*__errno()) = 0; /* ignore errors reading the file */ |
| 447 | return (NULL((void *)0)); |
| 448 | } |
| 449 | |
| 450 | /* there must be an address and at least one name */ |
| 451 | if (n < 2) |
| 452 | continue; |
| 453 | |
| 454 | if (reqtype == ASR_GETHOSTBYNAME) { |
| 455 | for (i = 1; i < n; i++) { |
| 456 | if (strcasecmp(data, tokens[i])) |
| 457 | continue; |
| 458 | if (inet_pton(family, tokens[0], addr) == 1) |
| 459 | goto found; |
| 460 | } |
| 461 | } else { |
| 462 | if (inet_pton(family, tokens[0], addr) == 1 && |
| 463 | memcmp(addr, data, datalen) == 0) |
| 464 | goto found; |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | found: |
| 469 | if ((h = hostent_alloc(family)) == NULL((void *)0)) |
| 470 | return (NULL((void *)0)); |
| 471 | if (hostent_set_cname(h, tokens[1], 0) == -1) |
| 472 | goto fail; |
| 473 | for (i = 2; i < n; i ++) |
| 474 | if (hostent_add_alias(h, tokens[i], 0) == -1) |
| 475 | goto fail; |
| 476 | if (hostent_add_addr(h, addr, h->h.h_length) == -1) |
| 477 | goto fail; |
| 478 | return (h); |
| 479 | fail: |
| 480 | free(h); |
| 481 | return (NULL((void *)0)); |
| 482 | } |
| 483 | |
| 484 | /* |
| 485 | * Fill the hostent from the given DNS packet. |
| 486 | */ |
| 487 | static struct hostent_ext * |
| 488 | hostent_from_packet(int reqtype, int family, char *pkt, size_t pktlen) |
| 489 | { |
| 490 | struct hostent_ext *h; |
| 491 | struct asr_unpack p; |
| 492 | struct asr_dns_header hdr; |
| 493 | struct asr_dns_query q; |
| 494 | struct asr_dns_rr rr; |
| 495 | char dname[MAXDNAME1025]; |
| 496 | |
| 497 | if ((h = hostent_alloc(family)) == NULL((void *)0)) |
| 498 | return (NULL((void *)0)); |
| 499 | |
| 500 | _asr_unpack_init(&p, pkt, pktlen); |
| 501 | _asr_unpack_header(&p, &hdr); |
| 502 | for (; hdr.qdcount; hdr.qdcount--) |
| 503 | _asr_unpack_query(&p, &q); |
| 504 | strlcpy(dname, q.q_dname, sizeof(dname)); |
| 505 | |
| 506 | for (; hdr.ancount; hdr.ancount--) { |
| 507 | _asr_unpack_rr(&p, &rr); |
| 508 | if (rr.rr_class != C_IN1) |
| 509 | continue; |
| 510 | switch (rr.rr_type) { |
| 511 | |
| 512 | case T_CNAME5: |
| 513 | if (reqtype == ASR_GETHOSTBYNAME) { |
| 514 | if (hostent_add_alias(h, rr.rr_dname, 1) == -1) |
| 515 | goto fail; |
| 516 | } else { |
| 517 | if (strcasecmp(rr.rr_dname, dname) == 0) |
| 518 | strlcpy(dname, rr.rr.cname.cname, |
| 519 | sizeof(dname)); |
| 520 | } |
| 521 | break; |
| 522 | |
| 523 | case T_PTR12: |
| 524 | if (reqtype != ASR_GETHOSTBYADDR) |
| 525 | break; |
| 526 | if (strcasecmp(rr.rr_dname, dname) != 0) |
| 527 | continue; |
| 528 | if (hostent_set_cname(h, rr.rr.ptr.ptrname, 1) == -1) |
| 529 | hostent_add_alias(h, rr.rr.ptr.ptrname, 1); |
| 530 | break; |
| 531 | |
| 532 | case T_A1: |
| 533 | if (reqtype != ASR_GETHOSTBYNAME) |
| 534 | break; |
| 535 | if (family != AF_INET2) |
| 536 | break; |
| 537 | if (hostent_set_cname(h, rr.rr_dname, 1) == -1) |
| 538 | ; |
| 539 | if (hostent_add_addr(h, &rr.rr.in_a.addr, 4) == -1) |
| 540 | goto fail; |
| 541 | break; |
| 542 | |
| 543 | case T_AAAA28: |
| 544 | if (reqtype != ASR_GETHOSTBYNAME) |
| 545 | break; |
| 546 | if (family != AF_INET624) |
| 547 | break; |
| 548 | if (hostent_set_cname(h, rr.rr_dname, 1) == -1) |
| 549 | ; |
| 550 | if (hostent_add_addr(h, &rr.rr.in_aaaa.addr6, 16) == -1) |
| 551 | goto fail; |
| 552 | break; |
| 553 | } |
| 554 | } |
| 555 | |
| 556 | return (h); |
| 557 | fail: |
| 558 | free(h); |
| 559 | return (NULL((void *)0)); |
| 560 | } |
| 561 | |
| 562 | static struct hostent_ext * |
| 563 | hostent_alloc(int family) |
| 564 | { |
| 565 | struct hostent_ext *h; |
| 566 | size_t alloc; |
| 567 | |
| 568 | alloc = sizeof(*h) + 1024; |
| 569 | if ((h = calloc(1, alloc)) == NULL((void *)0)) |
| 570 | return (NULL((void *)0)); |
| 571 | |
| 572 | h->h.h_addrtype = family; |
| 573 | h->h.h_length = (family == AF_INET2) ? 4 : 16; |
| 574 | h->h.h_aliases = h->aliases; |
| 575 | h->h.h_addr_list = h->addrs; |
| 576 | h->pos = (char *)(h) + sizeof(*h); |
| 577 | h->end = h->pos + 1024; |
| 578 | |
| 579 | return (h); |
| 580 | } |
| 581 | |
| 582 | static int |
| 583 | hostent_set_cname(struct hostent_ext *h, const char *name, int isdname) |
| 584 | { |
| 585 | char buf[MAXDNAME1025]; |
| 586 | size_t n; |
| 587 | |
| 588 | if (h->h.h_name) |
| 589 | return (-1); |
| 590 | |
| 591 | if (isdname) { |
| 592 | _asr_strdname(name, buf, sizeof buf); |
| 593 | buf[strlen(buf) - 1] = '\0'; |
| 594 | if (!res_hnok__res_hnok(buf)) |
| 595 | return (-1); |
| 596 | name = buf; |
| 597 | } |
| 598 | |
| 599 | n = strlen(name) + 1; |
| 600 | if (h->pos + n >= h->end) |
| 601 | return (-1); |
| 602 | |
| 603 | h->h.h_name = h->pos; |
| 604 | memmove(h->pos, name, n); |
| 605 | h->pos += n; |
| 606 | return (0); |
| 607 | } |
| 608 | |
| 609 | static int |
| 610 | hostent_add_alias(struct hostent_ext *h, const char *name, int isdname) |
| 611 | { |
| 612 | char buf[MAXDNAME1025]; |
| 613 | size_t i, n; |
| 614 | |
| 615 | for (i = 0; i < MAXALIASES35; i++) |
| 616 | if (h->aliases[i] == NULL((void *)0)) |
| 617 | break; |
| 618 | if (i == MAXALIASES35) |
| 619 | return (0); |
| 620 | |
| 621 | if (isdname) { |
| 622 | _asr_strdname(name, buf, sizeof buf); |
| 623 | buf[strlen(buf)-1] = '\0'; |
| 624 | if (!res_hnok__res_hnok(buf)) |
| 625 | return (-1); |
| 626 | name = buf; |
| 627 | } |
| 628 | |
| 629 | n = strlen(name) + 1; |
| 630 | if (h->pos + n >= h->end) |
| 631 | return (0); |
| 632 | |
| 633 | h->aliases[i] = h->pos; |
| 634 | memmove(h->pos, name, n); |
| 635 | h->pos += n; |
| 636 | return (0); |
| 637 | } |
| 638 | |
| 639 | static int |
| 640 | hostent_add_addr(struct hostent_ext *h, const void *addr, size_t size) |
| 641 | { |
| 642 | int i; |
| 643 | |
| 644 | for (i = 0; i < MAXADDRS35; i++) |
| 645 | if (h->addrs[i] == NULL((void *)0)) |
| 646 | break; |
| 647 | if (i == MAXADDRS35) |
| 648 | return (0); |
| 649 | |
| 650 | if (h->pos + size >= h->end) |
| 651 | return (0); |
| 652 | |
| 653 | h->addrs[i] = h->pos; |
| 654 | memmove(h->pos, addr, size); |
| 655 | h->pos += size; |
| 656 | return (0); |
| 657 | } |
| 658 | |
| 659 | static void |
| 660 | netent_from_hostent(struct asr_result *ar) |
| 661 | { |
| 662 | struct in_addr *addr; |
| 663 | struct netent_ext *n; |
| 664 | struct hostent_ext *h; |
| 665 | char **na, **ha; |
| 666 | size_t sz; |
| 667 | |
| 668 | /* Allocate and initialize the output. */ |
| 669 | if ((n = calloc(1, sizeof(*n) + 1024)) == NULL((void *)0)) { |
| 670 | ar->ar_h_errno = NETDB_INTERNAL-1; |
| 671 | ar->ar_errno = errno(*__errno()); |
| 672 | goto out; |
| 673 | } |
| 674 | n->pos = (char *)(n) + sizeof(*n); |
| 675 | n->end = n->pos + 1024; |
| 676 | n->n.n_name = n->pos; |
| 677 | n->n.n_aliases = n->aliases; |
| 678 | |
| 679 | /* Copy the fixed-size data. */ |
| 680 | h = (struct hostent_ext *)ar->ar_hostent; |
| 681 | addr = (struct in_addr *)h->h.h_addrh_addr_list[0]; |
| 682 | n->n.n_net = ntohl(addr->s_addr)(__uint32_t)(__builtin_constant_p(addr->s_addr) ? (__uint32_t )(((__uint32_t)(addr->s_addr) & 0xff) << 24 | (( __uint32_t)(addr->s_addr) & 0xff00) << 8 | ((__uint32_t )(addr->s_addr) & 0xff0000) >> 8 | ((__uint32_t) (addr->s_addr) & 0xff000000) >> 24) : __swap32md (addr->s_addr)); |
| 683 | n->n.n_addrtype = h->h.h_addrtype; |
| 684 | |
| 685 | /* Copy the network name. */ |
| 686 | sz = strlen(h->h.h_name) + 1; |
| 687 | memcpy(n->pos, h->h.h_name, sz); |
| 688 | n->pos += sz; |
| 689 | |
| 690 | /* |
| 691 | * Copy the aliases. |
| 692 | * No overflow check is needed because we are merely copying |
| 693 | * a part of the data from a structure of the same size. |
| 694 | */ |
| 695 | na = n->aliases; |
| 696 | for (ha = h->aliases; *ha != NULL((void *)0); ha++) { |
| 697 | sz = strlen(*ha) + 1; |
| 698 | memcpy(n->pos, *ha, sz); |
| 699 | *na++ = n->pos; |
| 700 | n->pos += sz; |
| 701 | } |
| 702 | *na = NULL((void *)0); |
| 703 | |
| 704 | /* Handle the return values. */ |
| 705 | ar->ar_netent = &n->n; |
| 706 | out: |
| 707 | free(ar->ar_hostent); |
| 708 | ar->ar_hostent = NULL((void *)0); |
| 709 | } |