| 1 | /************************************************* |
| 2 | * Exim - an Internet mail transport agent * |
| 3 | *************************************************/ |
| 4 | |
| 5 | /* Copyright (c) University of Cambridge 1995 - 2012 */ |
| 6 | /* See the file NOTICE for conditions of use and distribution. */ |
| 7 | |
| 8 | /* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or |
| 9 | directly via the DNS. When IPv6 is supported, getipnodebyname() and |
| 10 | getipnodebyaddr() may be used instead of gethostbyname() and gethostbyaddr(), |
| 11 | if the newer functions are available. This module also contains various other |
| 12 | functions concerned with hosts and addresses, and a random number function, |
| 13 | used for randomizing hosts with equal MXs but available for use in other parts |
| 14 | of Exim. */ |
| 15 | |
| 16 | |
| 17 | #include "exim.h" |
| 18 | |
| 19 | |
| 20 | /* Static variable for preserving the list of interface addresses in case it is |
| 21 | used more than once. */ |
| 22 | |
| 23 | static ip_address_item *local_interface_data = NULL; |
| 24 | |
| 25 | |
| 26 | #ifdef USE_INET_NTOA_FIX |
| 27 | /************************************************* |
| 28 | * Replacement for broken inet_ntoa() * |
| 29 | *************************************************/ |
| 30 | |
| 31 | /* On IRIX systems, gcc uses a different structure passing convention to the |
| 32 | native libraries. This causes inet_ntoa() to always yield 0.0.0.0 or |
| 33 | 255.255.255.255. To get round this, we provide a private version of the |
| 34 | function here. It is used only if USE_INET_NTOA_FIX is set, which should happen |
| 35 | only when gcc is in use on an IRIX system. Code send to me by J.T. Breitner, |
| 36 | with these comments: |
| 37 | |
| 38 | code by Stuart Levy |
| 39 | as seen in comp.sys.sgi.admin |
| 40 | |
| 41 | August 2005: Apparently this is also needed for AIX systems; USE_INET_NTOA_FIX |
| 42 | should now be set for them as well. |
| 43 | |
| 44 | Arguments: sa an in_addr structure |
| 45 | Returns: pointer to static text string |
| 46 | */ |
| 47 | |
| 48 | char * |
| 49 | inet_ntoa(struct in_addr sa) |
| 50 | { |
| 51 | static uschar addr[20]; |
| 52 | sprintf(addr, "%d.%d.%d.%d", |
| 53 | (US &sa.s_addr)[0], |
| 54 | (US &sa.s_addr)[1], |
| 55 | (US &sa.s_addr)[2], |
| 56 | (US &sa.s_addr)[3]); |
| 57 | return addr; |
| 58 | } |
| 59 | #endif |
| 60 | |
| 61 | |
| 62 | |
| 63 | /************************************************* |
| 64 | * Random number generator * |
| 65 | *************************************************/ |
| 66 | |
| 67 | /* This is a simple pseudo-random number generator. It does not have to be |
| 68 | very good for the uses to which it is put. When running the regression tests, |
| 69 | start with a fixed seed. |
| 70 | |
| 71 | If you need better, see vaguely_random_number() which is potentially stronger, |
| 72 | if a crypto library is available, but might end up just calling this instead. |
| 73 | |
| 74 | Arguments: |
| 75 | limit: one more than the largest number required |
| 76 | |
| 77 | Returns: a pseudo-random number in the range 0 to limit-1 |
| 78 | */ |
| 79 | |
| 80 | int |
| 81 | random_number(int limit) |
| 82 | { |
| 83 | if (limit < 1) |
| 84 | return 0; |
| 85 | if (random_seed == 0) |
| 86 | { |
| 87 | if (running_in_test_harness) random_seed = 42; else |
| 88 | { |
| 89 | int p = (int)getpid(); |
| 90 | random_seed = (int)time(NULL) ^ ((p << 16) | p); |
| 91 | } |
| 92 | } |
| 93 | random_seed = 1103515245 * random_seed + 12345; |
| 94 | return (unsigned int)(random_seed >> 16) % limit; |
| 95 | } |
| 96 | |
| 97 | |
| 98 | |
| 99 | /************************************************* |
| 100 | * Replace gethostbyname() when testing * |
| 101 | *************************************************/ |
| 102 | |
| 103 | /* This function is called instead of gethostbyname(), gethostbyname2(), or |
| 104 | getipnodebyname() when running in the test harness. It recognizes the name |
| 105 | "manyhome.test.ex" and generates a humungous number of IP addresses. It also |
| 106 | recognizes an unqualified "localhost" and forces it to the appropriate loopback |
| 107 | address. IP addresses are treated as literals. For other names, it uses the DNS |
| 108 | to find the host name. In the test harness, this means it will access only the |
| 109 | fake DNS resolver. |
| 110 | |
| 111 | Arguments: |
| 112 | name the host name or a textual IP address |
| 113 | af AF_INET or AF_INET6 |
| 114 | error_num where to put an error code: |
| 115 | HOST_NOT_FOUND/TRY_AGAIN/NO_RECOVERY/NO_DATA |
| 116 | |
| 117 | Returns: a hostent structure or NULL for an error |
| 118 | */ |
| 119 | |
| 120 | static struct hostent * |
| 121 | host_fake_gethostbyname(uschar *name, int af, int *error_num) |
| 122 | { |
| 123 | #if HAVE_IPV6 |
| 124 | int alen = (af == AF_INET)? sizeof(struct in_addr):sizeof(struct in6_addr); |
| 125 | #else |
| 126 | int alen = sizeof(struct in_addr); |
| 127 | #endif |
| 128 | |
| 129 | int ipa; |
| 130 | uschar *lname = name; |
| 131 | uschar *adds; |
| 132 | uschar **alist; |
| 133 | struct hostent *yield; |
| 134 | dns_answer dnsa; |
| 135 | dns_scan dnss; |
| 136 | dns_record *rr; |
| 137 | |
| 138 | DEBUG(D_host_lookup) |
| 139 | debug_printf("using host_fake_gethostbyname for %s (%s)\n", name, |
| 140 | (af == AF_INET)? "IPv4" : "IPv6"); |
| 141 | |
| 142 | /* Handle the name that needs a vast number of IP addresses */ |
| 143 | |
| 144 | if (Ustrcmp(name, "manyhome.test.ex") == 0 && af == AF_INET) |
| 145 | { |
| 146 | int i, j; |
| 147 | yield = store_get(sizeof(struct hostent)); |
| 148 | alist = store_get(2049 * sizeof(char *)); |
| 149 | adds = store_get(2048 * alen); |
| 150 | yield->h_name = CS name; |
| 151 | yield->h_aliases = NULL; |
| 152 | yield->h_addrtype = af; |
| 153 | yield->h_length = alen; |
| 154 | yield->h_addr_list = CSS alist; |
| 155 | for (i = 104; i <= 111; i++) |
| 156 | { |
| 157 | for (j = 0; j <= 255; j++) |
| 158 | { |
| 159 | *alist++ = adds; |
| 160 | *adds++ = 10; |
| 161 | *adds++ = 250; |
| 162 | *adds++ = i; |
| 163 | *adds++ = j; |
| 164 | } |
| 165 | } |
| 166 | *alist = NULL; |
| 167 | return yield; |
| 168 | } |
| 169 | |
| 170 | /* Handle unqualified "localhost" */ |
| 171 | |
| 172 | if (Ustrcmp(name, "localhost") == 0) |
| 173 | lname = (af == AF_INET)? US"127.0.0.1" : US"::1"; |
| 174 | |
| 175 | /* Handle a literal IP address */ |
| 176 | |
| 177 | ipa = string_is_ip_address(lname, NULL); |
| 178 | if (ipa != 0) |
| 179 | { |
| 180 | if ((ipa == 4 && af == AF_INET) || |
| 181 | (ipa == 6 && af == AF_INET6)) |
| 182 | { |
| 183 | int i, n; |
| 184 | int x[4]; |
| 185 | yield = store_get(sizeof(struct hostent)); |
| 186 | alist = store_get(2 * sizeof(char *)); |
| 187 | adds = store_get(alen); |
| 188 | yield->h_name = CS name; |
| 189 | yield->h_aliases = NULL; |
| 190 | yield->h_addrtype = af; |
| 191 | yield->h_length = alen; |
| 192 | yield->h_addr_list = CSS alist; |
| 193 | *alist++ = adds; |
| 194 | n = host_aton(lname, x); |
| 195 | for (i = 0; i < n; i++) |
| 196 | { |
| 197 | int y = x[i]; |
| 198 | *adds++ = (y >> 24) & 255; |
| 199 | *adds++ = (y >> 16) & 255; |
| 200 | *adds++ = (y >> 8) & 255; |
| 201 | *adds++ = y & 255; |
| 202 | } |
| 203 | *alist = NULL; |
| 204 | } |
| 205 | |
| 206 | /* Wrong kind of literal address */ |
| 207 | |
| 208 | else |
| 209 | { |
| 210 | *error_num = HOST_NOT_FOUND; |
| 211 | return NULL; |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | /* Handle a host name */ |
| 216 | |
| 217 | else |
| 218 | { |
| 219 | int type = (af == AF_INET)? T_A:T_AAAA; |
| 220 | int rc = dns_lookup(&dnsa, lname, type, NULL); |
| 221 | int count = 0; |
| 222 | |
| 223 | lookup_dnssec_authenticated = NULL; |
| 224 | |
| 225 | switch(rc) |
| 226 | { |
| 227 | case DNS_SUCCEED: break; |
| 228 | case DNS_NOMATCH: *error_num = HOST_NOT_FOUND; return NULL; |
| 229 | case DNS_NODATA: *error_num = NO_DATA; return NULL; |
| 230 | case DNS_AGAIN: *error_num = TRY_AGAIN; return NULL; |
| 231 | default: |
| 232 | case DNS_FAIL: *error_num = NO_RECOVERY; return NULL; |
| 233 | } |
| 234 | |
| 235 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 236 | rr != NULL; |
| 237 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 238 | { |
| 239 | if (rr->type == type) count++; |
| 240 | } |
| 241 | |
| 242 | yield = store_get(sizeof(struct hostent)); |
| 243 | alist = store_get((count + 1) * sizeof(char **)); |
| 244 | adds = store_get(count *alen); |
| 245 | |
| 246 | yield->h_name = CS name; |
| 247 | yield->h_aliases = NULL; |
| 248 | yield->h_addrtype = af; |
| 249 | yield->h_length = alen; |
| 250 | yield->h_addr_list = CSS alist; |
| 251 | |
| 252 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 253 | rr != NULL; |
| 254 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 255 | { |
| 256 | int i, n; |
| 257 | int x[4]; |
| 258 | dns_address *da; |
| 259 | if (rr->type != type) continue; |
| 260 | da = dns_address_from_rr(&dnsa, rr); |
| 261 | *alist++ = adds; |
| 262 | n = host_aton(da->address, x); |
| 263 | for (i = 0; i < n; i++) |
| 264 | { |
| 265 | int y = x[i]; |
| 266 | *adds++ = (y >> 24) & 255; |
| 267 | *adds++ = (y >> 16) & 255; |
| 268 | *adds++ = (y >> 8) & 255; |
| 269 | *adds++ = y & 255; |
| 270 | } |
| 271 | } |
| 272 | *alist = NULL; |
| 273 | } |
| 274 | |
| 275 | return yield; |
| 276 | } |
| 277 | |
| 278 | |
| 279 | |
| 280 | /************************************************* |
| 281 | * Build chain of host items from list * |
| 282 | *************************************************/ |
| 283 | |
| 284 | /* This function builds a chain of host items from a textual list of host |
| 285 | names. It does not do any lookups. If randomize is true, the chain is build in |
| 286 | a randomized order. There may be multiple groups of independently randomized |
| 287 | hosts; they are delimited by a host name consisting of just "+". |
| 288 | |
| 289 | Arguments: |
| 290 | anchor anchor for the chain |
| 291 | list text list |
| 292 | randomize TRUE for randomizing |
| 293 | |
| 294 | Returns: nothing |
| 295 | */ |
| 296 | |
| 297 | void |
| 298 | host_build_hostlist(host_item **anchor, uschar *list, BOOL randomize) |
| 299 | { |
| 300 | int sep = 0; |
| 301 | int fake_mx = MX_NONE; /* This value is actually -1 */ |
| 302 | uschar *name; |
| 303 | uschar buffer[1024]; |
| 304 | |
| 305 | if (list == NULL) return; |
| 306 | if (randomize) fake_mx--; /* Start at -2 for randomizing */ |
| 307 | |
| 308 | *anchor = NULL; |
| 309 | |
| 310 | while ((name = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) |
| 311 | { |
| 312 | host_item *h; |
| 313 | |
| 314 | if (name[0] == '+' && name[1] == 0) /* "+" delimits a randomized group */ |
| 315 | { /* ignore if not randomizing */ |
| 316 | if (randomize) fake_mx--; |
| 317 | continue; |
| 318 | } |
| 319 | |
| 320 | h = store_get(sizeof(host_item)); |
| 321 | h->name = string_copy(name); |
| 322 | h->address = NULL; |
| 323 | h->port = PORT_NONE; |
| 324 | h->mx = fake_mx; |
| 325 | h->sort_key = randomize? (-fake_mx)*1000 + random_number(1000) : 0; |
| 326 | h->status = hstatus_unknown; |
| 327 | h->why = hwhy_unknown; |
| 328 | h->last_try = 0; |
| 329 | |
| 330 | if (*anchor == NULL) |
| 331 | { |
| 332 | h->next = NULL; |
| 333 | *anchor = h; |
| 334 | } |
| 335 | else |
| 336 | { |
| 337 | host_item *hh = *anchor; |
| 338 | if (h->sort_key < hh->sort_key) |
| 339 | { |
| 340 | h->next = hh; |
| 341 | *anchor = h; |
| 342 | } |
| 343 | else |
| 344 | { |
| 345 | while (hh->next != NULL && h->sort_key >= (hh->next)->sort_key) |
| 346 | hh = hh->next; |
| 347 | h->next = hh->next; |
| 348 | hh->next = h; |
| 349 | } |
| 350 | } |
| 351 | } |
| 352 | } |
| 353 | |
| 354 | |
| 355 | |
| 356 | |
| 357 | |
| 358 | /************************************************* |
| 359 | * Extract port from address string * |
| 360 | *************************************************/ |
| 361 | |
| 362 | /* In the spool file, and in the -oMa and -oMi options, a host plus port is |
| 363 | given as an IP address followed by a dot and a port number. This function |
| 364 | decodes this. |
| 365 | |
| 366 | An alternative format for the -oMa and -oMi options is [ip address]:port which |
| 367 | is what Exim 4 uses for output, because it seems to becoming commonly used, |
| 368 | whereas the dot form confuses some programs/people. So we recognize that form |
| 369 | too. |
| 370 | |
| 371 | Argument: |
| 372 | address points to the string; if there is a port, the '.' in the string |
| 373 | is overwritten with zero to terminate the address; if the string |
| 374 | is in the [xxx]:ppp format, the address is shifted left and the |
| 375 | brackets are removed |
| 376 | |
| 377 | Returns: 0 if there is no port, else the port number. If there's a syntax |
| 378 | error, leave the incoming address alone, and return 0. |
| 379 | */ |
| 380 | |
| 381 | int |
| 382 | host_address_extract_port(uschar *address) |
| 383 | { |
| 384 | int port = 0; |
| 385 | uschar *endptr; |
| 386 | |
| 387 | /* Handle the "bracketed with colon on the end" format */ |
| 388 | |
| 389 | if (*address == '[') |
| 390 | { |
| 391 | uschar *rb = address + 1; |
| 392 | while (*rb != 0 && *rb != ']') rb++; |
| 393 | if (*rb++ == 0) return 0; /* Missing ]; leave invalid address */ |
| 394 | if (*rb == ':') |
| 395 | { |
| 396 | port = Ustrtol(rb + 1, &endptr, 10); |
| 397 | if (*endptr != 0) return 0; /* Invalid port; leave invalid address */ |
| 398 | } |
| 399 | else if (*rb != 0) return 0; /* Bad syntax; leave invalid address */ |
| 400 | memmove(address, address + 1, rb - address - 2); |
| 401 | rb[-2] = 0; |
| 402 | } |
| 403 | |
| 404 | /* Handle the "dot on the end" format */ |
| 405 | |
| 406 | else |
| 407 | { |
| 408 | int skip = -3; /* Skip 3 dots in IPv4 addresses */ |
| 409 | address--; |
| 410 | while (*(++address) != 0) |
| 411 | { |
| 412 | int ch = *address; |
| 413 | if (ch == ':') skip = 0; /* Skip 0 dots in IPv6 addresses */ |
| 414 | else if (ch == '.' && skip++ >= 0) break; |
| 415 | } |
| 416 | if (*address == 0) return 0; |
| 417 | port = Ustrtol(address + 1, &endptr, 10); |
| 418 | if (*endptr != 0) return 0; /* Invalid port; leave invalid address */ |
| 419 | *address = 0; |
| 420 | } |
| 421 | |
| 422 | return port; |
| 423 | } |
| 424 | |
| 425 | |
| 426 | /************************************************* |
| 427 | * Get port from a host item's name * |
| 428 | *************************************************/ |
| 429 | |
| 430 | /* This function is called when finding the IP address for a host that is in a |
| 431 | list of hosts explicitly configured, such as in the manualroute router, or in a |
| 432 | fallback hosts list. We see if there is a port specification at the end of the |
| 433 | host name, and if so, remove it. A minimum length of 3 is required for the |
| 434 | original name; nothing shorter is recognized as having a port. |
| 435 | |
| 436 | We test for a name ending with a sequence of digits; if preceded by colon we |
| 437 | have a port if the character before the colon is ] and the name starts with [ |
| 438 | or if there are no other colons in the name (i.e. it's not an IPv6 address). |
| 439 | |
| 440 | Arguments: pointer to the host item |
| 441 | Returns: a port number or PORT_NONE |
| 442 | */ |
| 443 | |
| 444 | int |
| 445 | host_item_get_port(host_item *h) |
| 446 | { |
| 447 | uschar *p; |
| 448 | int port, x; |
| 449 | int len = Ustrlen(h->name); |
| 450 | |
| 451 | if (len < 3 || (p = h->name + len - 1, !isdigit(*p))) return PORT_NONE; |
| 452 | |
| 453 | /* Extract potential port number */ |
| 454 | |
| 455 | port = *p-- - '0'; |
| 456 | x = 10; |
| 457 | |
| 458 | while (p > h->name + 1 && isdigit(*p)) |
| 459 | { |
| 460 | port += (*p-- - '0') * x; |
| 461 | x *= 10; |
| 462 | } |
| 463 | |
| 464 | /* The smallest value of p at this point is h->name + 1. */ |
| 465 | |
| 466 | if (*p != ':') return PORT_NONE; |
| 467 | |
| 468 | if (p[-1] == ']' && h->name[0] == '[') |
| 469 | h->name = string_copyn(h->name + 1, p - h->name - 2); |
| 470 | else if (Ustrchr(h->name, ':') == p) |
| 471 | h->name = string_copyn(h->name, p - h->name); |
| 472 | else return PORT_NONE; |
| 473 | |
| 474 | DEBUG(D_route|D_host_lookup) debug_printf("host=%s port=%d\n", h->name, port); |
| 475 | return port; |
| 476 | } |
| 477 | |
| 478 | |
| 479 | |
| 480 | #ifndef STAND_ALONE /* Omit when standalone testing */ |
| 481 | |
| 482 | /************************************************* |
| 483 | * Build sender_fullhost and sender_rcvhost * |
| 484 | *************************************************/ |
| 485 | |
| 486 | /* This function is called when sender_host_name and/or sender_helo_name |
| 487 | have been set. Or might have been set - for a local message read off the spool |
| 488 | they won't be. In that case, do nothing. Otherwise, set up the fullhost string |
| 489 | as follows: |
| 490 | |
| 491 | (a) No sender_host_name or sender_helo_name: "[ip address]" |
| 492 | (b) Just sender_host_name: "host_name [ip address]" |
| 493 | (c) Just sender_helo_name: "(helo_name) [ip address]" unless helo is IP |
| 494 | in which case: "[ip address}" |
| 495 | (d) The two are identical: "host_name [ip address]" includes helo = IP |
| 496 | (e) The two are different: "host_name (helo_name) [ip address]" |
| 497 | |
| 498 | If log_incoming_port is set, the sending host's port number is added to the IP |
| 499 | address. |
| 500 | |
| 501 | This function also builds sender_rcvhost for use in Received: lines, whose |
| 502 | syntax is a bit different. This value also includes the RFC 1413 identity. |
| 503 | There wouldn't be two different variables if I had got all this right in the |
| 504 | first place. |
| 505 | |
| 506 | Because this data may survive over more than one incoming SMTP message, it has |
| 507 | to be in permanent store. |
| 508 | |
| 509 | Arguments: none |
| 510 | Returns: nothing |
| 511 | */ |
| 512 | |
| 513 | void |
| 514 | host_build_sender_fullhost(void) |
| 515 | { |
| 516 | BOOL show_helo = TRUE; |
| 517 | uschar *address; |
| 518 | int len; |
| 519 | int old_pool = store_pool; |
| 520 | |
| 521 | if (sender_host_address == NULL) return; |
| 522 | |
| 523 | store_pool = POOL_PERM; |
| 524 | |
| 525 | /* Set up address, with or without the port. After discussion, it seems that |
| 526 | the only format that doesn't cause trouble is [aaaa]:pppp. However, we can't |
| 527 | use this directly as the first item for Received: because it ain't an RFC 2822 |
| 528 | domain. Sigh. */ |
| 529 | |
| 530 | address = string_sprintf("[%s]:%d", sender_host_address, sender_host_port); |
| 531 | if ((log_extra_selector & LX_incoming_port) == 0 || sender_host_port <= 0) |
| 532 | *(Ustrrchr(address, ':')) = 0; |
| 533 | |
| 534 | /* If there's no EHLO/HELO data, we can't show it. */ |
| 535 | |
| 536 | if (sender_helo_name == NULL) show_helo = FALSE; |
| 537 | |
| 538 | /* If HELO/EHLO was followed by an IP literal, it's messy because of two |
| 539 | features of IPv6. Firstly, there's the "IPv6:" prefix (Exim is liberal and |
| 540 | doesn't require this, for historical reasons). Secondly, IPv6 addresses may not |
| 541 | be given in canonical form, so we have to canonicize them before comparing. As |
| 542 | it happens, the code works for both IPv4 and IPv6. */ |
| 543 | |
| 544 | else if (sender_helo_name[0] == '[' && |
| 545 | sender_helo_name[(len=Ustrlen(sender_helo_name))-1] == ']') |
| 546 | { |
| 547 | int offset = 1; |
| 548 | uschar *helo_ip; |
| 549 | |
| 550 | if (strncmpic(sender_helo_name + 1, US"IPv6:", 5) == 0) offset += 5; |
| 551 | if (strncmpic(sender_helo_name + 1, US"IPv4:", 5) == 0) offset += 5; |
| 552 | |
| 553 | helo_ip = string_copyn(sender_helo_name + offset, len - offset - 1); |
| 554 | |
| 555 | if (string_is_ip_address(helo_ip, NULL) != 0) |
| 556 | { |
| 557 | int x[4], y[4]; |
| 558 | int sizex, sizey; |
| 559 | uschar ipx[48], ipy[48]; /* large enough for full IPv6 */ |
| 560 | |
| 561 | sizex = host_aton(helo_ip, x); |
| 562 | sizey = host_aton(sender_host_address, y); |
| 563 | |
| 564 | (void)host_nmtoa(sizex, x, -1, ipx, ':'); |
| 565 | (void)host_nmtoa(sizey, y, -1, ipy, ':'); |
| 566 | |
| 567 | if (strcmpic(ipx, ipy) == 0) show_helo = FALSE; |
| 568 | } |
| 569 | } |
| 570 | |
| 571 | /* Host name is not verified */ |
| 572 | |
| 573 | if (sender_host_name == NULL) |
| 574 | { |
| 575 | uschar *portptr = Ustrstr(address, "]:"); |
| 576 | int size = 0; |
| 577 | int ptr = 0; |
| 578 | int adlen; /* Sun compiler doesn't like ++ in initializers */ |
| 579 | |
| 580 | adlen = (portptr == NULL)? Ustrlen(address) : (++portptr - address); |
| 581 | sender_fullhost = (sender_helo_name == NULL)? address : |
| 582 | string_sprintf("(%s) %s", sender_helo_name, address); |
| 583 | |
| 584 | sender_rcvhost = string_cat(NULL, &size, &ptr, address, adlen); |
| 585 | |
| 586 | if (sender_ident != NULL || show_helo || portptr != NULL) |
| 587 | { |
| 588 | int firstptr; |
| 589 | sender_rcvhost = string_cat(sender_rcvhost, &size, &ptr, US" (", 2); |
| 590 | firstptr = ptr; |
| 591 | |
| 592 | if (portptr != NULL) |
| 593 | sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, US"port=", |
| 594 | portptr + 1); |
| 595 | |
| 596 | if (show_helo) |
| 597 | sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, |
| 598 | (firstptr == ptr)? US"helo=" : US" helo=", sender_helo_name); |
| 599 | |
| 600 | if (sender_ident != NULL) |
| 601 | sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, |
| 602 | (firstptr == ptr)? US"ident=" : US" ident=", sender_ident); |
| 603 | |
| 604 | sender_rcvhost = string_cat(sender_rcvhost, &size, &ptr, US")", 1); |
| 605 | } |
| 606 | |
| 607 | sender_rcvhost[ptr] = 0; /* string_cat() always leaves room */ |
| 608 | |
| 609 | /* Release store, because string_cat allocated a minimum of 100 bytes that |
| 610 | are rarely completely used. */ |
| 611 | |
| 612 | store_reset(sender_rcvhost + ptr + 1); |
| 613 | } |
| 614 | |
| 615 | /* Host name is known and verified. Unless we've already found that the HELO |
| 616 | data matches the IP address, compare it with the name. */ |
| 617 | |
| 618 | else |
| 619 | { |
| 620 | if (show_helo && strcmpic(sender_host_name, sender_helo_name) == 0) |
| 621 | show_helo = FALSE; |
| 622 | |
| 623 | if (show_helo) |
| 624 | { |
| 625 | sender_fullhost = string_sprintf("%s (%s) %s", sender_host_name, |
| 626 | sender_helo_name, address); |
| 627 | sender_rcvhost = (sender_ident == NULL)? |
| 628 | string_sprintf("%s (%s helo=%s)", sender_host_name, |
| 629 | address, sender_helo_name) : |
| 630 | string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name, |
| 631 | address, sender_helo_name, sender_ident); |
| 632 | } |
| 633 | else |
| 634 | { |
| 635 | sender_fullhost = string_sprintf("%s %s", sender_host_name, address); |
| 636 | sender_rcvhost = (sender_ident == NULL)? |
| 637 | string_sprintf("%s (%s)", sender_host_name, address) : |
| 638 | string_sprintf("%s (%s ident=%s)", sender_host_name, address, |
| 639 | sender_ident); |
| 640 | } |
| 641 | } |
| 642 | |
| 643 | store_pool = old_pool; |
| 644 | |
| 645 | DEBUG(D_host_lookup) debug_printf("sender_fullhost = %s\n", sender_fullhost); |
| 646 | DEBUG(D_host_lookup) debug_printf("sender_rcvhost = %s\n", sender_rcvhost); |
| 647 | } |
| 648 | |
| 649 | |
| 650 | |
| 651 | /************************************************* |
| 652 | * Build host+ident message * |
| 653 | *************************************************/ |
| 654 | |
| 655 | /* Used when logging rejections and various ACL and SMTP incidents. The text |
| 656 | return depends on whether sender_fullhost and sender_ident are set or not: |
| 657 | |
| 658 | no ident, no host => U=unknown |
| 659 | no ident, host set => H=sender_fullhost |
| 660 | ident set, no host => U=ident |
| 661 | ident set, host set => H=sender_fullhost U=ident |
| 662 | |
| 663 | Arguments: |
| 664 | useflag TRUE if first item to be flagged (H= or U=); if there are two |
| 665 | items, the second is always flagged |
| 666 | |
| 667 | Returns: pointer to a string in big_buffer |
| 668 | */ |
| 669 | |
| 670 | uschar * |
| 671 | host_and_ident(BOOL useflag) |
| 672 | { |
| 673 | if (sender_fullhost == NULL) |
| 674 | { |
| 675 | (void)string_format(big_buffer, big_buffer_size, "%s%s", useflag? "U=" : "", |
| 676 | (sender_ident == NULL)? US"unknown" : sender_ident); |
| 677 | } |
| 678 | else |
| 679 | { |
| 680 | uschar *flag = useflag? US"H=" : US""; |
| 681 | uschar *iface = US""; |
| 682 | if ((log_extra_selector & LX_incoming_interface) != 0 && |
| 683 | interface_address != NULL) |
| 684 | iface = string_sprintf(" I=[%s]:%d", interface_address, interface_port); |
| 685 | if (sender_ident == NULL) |
| 686 | (void)string_format(big_buffer, big_buffer_size, "%s%s%s", |
| 687 | flag, sender_fullhost, iface); |
| 688 | else |
| 689 | (void)string_format(big_buffer, big_buffer_size, "%s%s%s U=%s", |
| 690 | flag, sender_fullhost, iface, sender_ident); |
| 691 | } |
| 692 | return big_buffer; |
| 693 | } |
| 694 | |
| 695 | #endif /* STAND_ALONE */ |
| 696 | |
| 697 | |
| 698 | |
| 699 | |
| 700 | /************************************************* |
| 701 | * Build list of local interfaces * |
| 702 | *************************************************/ |
| 703 | |
| 704 | /* This function interprets the contents of the local_interfaces or |
| 705 | extra_local_interfaces options, and creates an ip_address_item block for each |
| 706 | item on the list. There is no special interpretation of any IP addresses; in |
| 707 | particular, 0.0.0.0 and ::0 are returned without modification. If any address |
| 708 | includes a port, it is set in the block. Otherwise the port value is set to |
| 709 | zero. |
| 710 | |
| 711 | Arguments: |
| 712 | list the list |
| 713 | name the name of the option being expanded |
| 714 | |
| 715 | Returns: a chain of ip_address_items, each containing to a textual |
| 716 | version of an IP address, and a port number (host order) or |
| 717 | zero if no port was given with the address |
| 718 | */ |
| 719 | |
| 720 | ip_address_item * |
| 721 | host_build_ifacelist(uschar *list, uschar *name) |
| 722 | { |
| 723 | int sep = 0; |
| 724 | uschar *s; |
| 725 | uschar buffer[64]; |
| 726 | ip_address_item *yield = NULL; |
| 727 | ip_address_item *last = NULL; |
| 728 | ip_address_item *next; |
| 729 | |
| 730 | while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) |
| 731 | { |
| 732 | int ipv; |
| 733 | int port = host_address_extract_port(s); /* Leaves just the IP address */ |
| 734 | if ((ipv = string_is_ip_address(s, NULL)) == 0) |
| 735 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Malformed IP address \"%s\" in %s", |
| 736 | s, name); |
| 737 | |
| 738 | /* Skip IPv6 addresses if IPv6 is disabled. */ |
| 739 | |
| 740 | if (disable_ipv6 && ipv == 6) continue; |
| 741 | |
| 742 | /* This use of strcpy() is OK because we have checked that s is a valid IP |
| 743 | address above. The field in the ip_address_item is large enough to hold an |
| 744 | IPv6 address. */ |
| 745 | |
| 746 | next = store_get(sizeof(ip_address_item)); |
| 747 | next->next = NULL; |
| 748 | Ustrcpy(next->address, s); |
| 749 | next->port = port; |
| 750 | next->v6_include_v4 = FALSE; |
| 751 | |
| 752 | if (yield == NULL) yield = last = next; else |
| 753 | { |
| 754 | last->next = next; |
| 755 | last = next; |
| 756 | } |
| 757 | } |
| 758 | |
| 759 | return yield; |
| 760 | } |
| 761 | |
| 762 | |
| 763 | |
| 764 | |
| 765 | |
| 766 | /************************************************* |
| 767 | * Find addresses on local interfaces * |
| 768 | *************************************************/ |
| 769 | |
| 770 | /* This function finds the addresses of local IP interfaces. These are used |
| 771 | when testing for routing to the local host. As the function may be called more |
| 772 | than once, the list is preserved in permanent store, pointed to by a static |
| 773 | variable, to save doing the work more than once per process. |
| 774 | |
| 775 | The generic list of interfaces is obtained by calling host_build_ifacelist() |
| 776 | for local_interfaces and extra_local_interfaces. This list scanned to remove |
| 777 | duplicates (which may exist with different ports - not relevant here). If |
| 778 | either of the wildcard IP addresses (0.0.0.0 and ::0) are encountered, they are |
| 779 | replaced by the appropriate (IPv4 or IPv6) list of actual local interfaces, |
| 780 | obtained from os_find_running_interfaces(). |
| 781 | |
| 782 | Arguments: none |
| 783 | Returns: a chain of ip_address_items, each containing to a textual |
| 784 | version of an IP address; the port numbers are not relevant |
| 785 | */ |
| 786 | |
| 787 | |
| 788 | /* First, a local subfunction to add an interface to a list in permanent store, |
| 789 | but only if there isn't a previous copy of that address on the list. */ |
| 790 | |
| 791 | static ip_address_item * |
| 792 | add_unique_interface(ip_address_item *list, ip_address_item *ipa) |
| 793 | { |
| 794 | ip_address_item *ipa2; |
| 795 | for (ipa2 = list; ipa2 != NULL; ipa2 = ipa2->next) |
| 796 | if (Ustrcmp(ipa2->address, ipa->address) == 0) return list; |
| 797 | ipa2 = store_get_perm(sizeof(ip_address_item)); |
| 798 | *ipa2 = *ipa; |
| 799 | ipa2->next = list; |
| 800 | return ipa2; |
| 801 | } |
| 802 | |
| 803 | |
| 804 | /* This is the globally visible function */ |
| 805 | |
| 806 | ip_address_item * |
| 807 | host_find_interfaces(void) |
| 808 | { |
| 809 | ip_address_item *running_interfaces = NULL; |
| 810 | |
| 811 | if (local_interface_data == NULL) |
| 812 | { |
| 813 | void *reset_item = store_get(0); |
| 814 | ip_address_item *dlist = host_build_ifacelist(local_interfaces, |
| 815 | US"local_interfaces"); |
| 816 | ip_address_item *xlist = host_build_ifacelist(extra_local_interfaces, |
| 817 | US"extra_local_interfaces"); |
| 818 | ip_address_item *ipa; |
| 819 | |
| 820 | if (dlist == NULL) dlist = xlist; else |
| 821 | { |
| 822 | for (ipa = dlist; ipa->next != NULL; ipa = ipa->next); |
| 823 | ipa->next = xlist; |
| 824 | } |
| 825 | |
| 826 | for (ipa = dlist; ipa != NULL; ipa = ipa->next) |
| 827 | { |
| 828 | if (Ustrcmp(ipa->address, "0.0.0.0") == 0 || |
| 829 | Ustrcmp(ipa->address, "::0") == 0) |
| 830 | { |
| 831 | ip_address_item *ipa2; |
| 832 | BOOL ipv6 = ipa->address[0] == ':'; |
| 833 | if (running_interfaces == NULL) |
| 834 | running_interfaces = os_find_running_interfaces(); |
| 835 | for (ipa2 = running_interfaces; ipa2 != NULL; ipa2 = ipa2->next) |
| 836 | { |
| 837 | if ((Ustrchr(ipa2->address, ':') != NULL) == ipv6) |
| 838 | local_interface_data = add_unique_interface(local_interface_data, |
| 839 | ipa2); |
| 840 | } |
| 841 | } |
| 842 | else |
| 843 | { |
| 844 | local_interface_data = add_unique_interface(local_interface_data, ipa); |
| 845 | DEBUG(D_interface) |
| 846 | { |
| 847 | debug_printf("Configured local interface: address=%s", ipa->address); |
| 848 | if (ipa->port != 0) debug_printf(" port=%d", ipa->port); |
| 849 | debug_printf("\n"); |
| 850 | } |
| 851 | } |
| 852 | } |
| 853 | store_reset(reset_item); |
| 854 | } |
| 855 | |
| 856 | return local_interface_data; |
| 857 | } |
| 858 | |
| 859 | |
| 860 | |
| 861 | |
| 862 | |
| 863 | /************************************************* |
| 864 | * Convert network IP address to text * |
| 865 | *************************************************/ |
| 866 | |
| 867 | /* Given an IPv4 or IPv6 address in binary, convert it to a text |
| 868 | string and return the result in a piece of new store. The address can |
| 869 | either be given directly, or passed over in a sockaddr structure. Note |
| 870 | that this isn't the converse of host_aton() because of byte ordering |
| 871 | differences. See host_nmtoa() below. |
| 872 | |
| 873 | Arguments: |
| 874 | type if < 0 then arg points to a sockaddr, else |
| 875 | either AF_INET or AF_INET6 |
| 876 | arg points to a sockaddr if type is < 0, or |
| 877 | points to an IPv4 address (32 bits), or |
| 878 | points to an IPv6 address (128 bits), |
| 879 | in both cases, in network byte order |
| 880 | buffer if NULL, the result is returned in gotten store; |
| 881 | else points to a buffer to hold the answer |
| 882 | portptr points to where to put the port number, if non NULL; only |
| 883 | used when type < 0 |
| 884 | |
| 885 | Returns: pointer to character string |
| 886 | */ |
| 887 | |
| 888 | uschar * |
| 889 | host_ntoa(int type, const void *arg, uschar *buffer, int *portptr) |
| 890 | { |
| 891 | uschar *yield; |
| 892 | |
| 893 | /* The new world. It is annoying that we have to fish out the address from |
| 894 | different places in the block, depending on what kind of address it is. It |
| 895 | is also a pain that inet_ntop() returns a const uschar *, whereas the IPv4 |
| 896 | function inet_ntoa() returns just uschar *, and some picky compilers insist |
| 897 | on warning if one assigns a const uschar * to a uschar *. Hence the casts. */ |
| 898 | |
| 899 | #if HAVE_IPV6 |
| 900 | uschar addr_buffer[46]; |
| 901 | if (type < 0) |
| 902 | { |
| 903 | int family = ((struct sockaddr *)arg)->sa_family; |
| 904 | if (family == AF_INET6) |
| 905 | { |
| 906 | struct sockaddr_in6 *sk = (struct sockaddr_in6 *)arg; |
| 907 | yield = (uschar *)inet_ntop(family, &(sk->sin6_addr), CS addr_buffer, |
| 908 | sizeof(addr_buffer)); |
| 909 | if (portptr != NULL) *portptr = ntohs(sk->sin6_port); |
| 910 | } |
| 911 | else |
| 912 | { |
| 913 | struct sockaddr_in *sk = (struct sockaddr_in *)arg; |
| 914 | yield = (uschar *)inet_ntop(family, &(sk->sin_addr), CS addr_buffer, |
| 915 | sizeof(addr_buffer)); |
| 916 | if (portptr != NULL) *portptr = ntohs(sk->sin_port); |
| 917 | } |
| 918 | } |
| 919 | else |
| 920 | { |
| 921 | yield = (uschar *)inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer)); |
| 922 | } |
| 923 | |
| 924 | /* If the result is a mapped IPv4 address, show it in V4 format. */ |
| 925 | |
| 926 | if (Ustrncmp(yield, "::ffff:", 7) == 0) yield += 7; |
| 927 | |
| 928 | #else /* HAVE_IPV6 */ |
| 929 | |
| 930 | /* The old world */ |
| 931 | |
| 932 | if (type < 0) |
| 933 | { |
| 934 | yield = US inet_ntoa(((struct sockaddr_in *)arg)->sin_addr); |
| 935 | if (portptr != NULL) *portptr = ntohs(((struct sockaddr_in *)arg)->sin_port); |
| 936 | } |
| 937 | else |
| 938 | yield = US inet_ntoa(*((struct in_addr *)arg)); |
| 939 | #endif |
| 940 | |
| 941 | /* If there is no buffer, put the string into some new store. */ |
| 942 | |
| 943 | if (buffer == NULL) return string_copy(yield); |
| 944 | |
| 945 | /* Callers of this function with a non-NULL buffer must ensure that it is |
| 946 | large enough to hold an IPv6 address, namely, at least 46 bytes. That's what |
| 947 | makes this use of strcpy() OK. */ |
| 948 | |
| 949 | Ustrcpy(buffer, yield); |
| 950 | return buffer; |
| 951 | } |
| 952 | |
| 953 | |
| 954 | |
| 955 | |
| 956 | /************************************************* |
| 957 | * Convert address text to binary * |
| 958 | *************************************************/ |
| 959 | |
| 960 | /* Given the textual form of an IP address, convert it to binary in an |
| 961 | array of ints. IPv4 addresses occupy one int; IPv6 addresses occupy 4 ints. |
| 962 | The result has the first byte in the most significant byte of the first int. In |
| 963 | other words, the result is not in network byte order, but in host byte order. |
| 964 | As a result, this is not the converse of host_ntoa(), which expects network |
| 965 | byte order. See host_nmtoa() below. |
| 966 | |
| 967 | Arguments: |
| 968 | address points to the textual address, checked for syntax |
| 969 | bin points to an array of 4 ints |
| 970 | |
| 971 | Returns: the number of ints used |
| 972 | */ |
| 973 | |
| 974 | int |
| 975 | host_aton(uschar *address, int *bin) |
| 976 | { |
| 977 | int x[4]; |
| 978 | int v4offset = 0; |
| 979 | |
| 980 | /* Handle IPv6 address, which may end with an IPv4 address. It may also end |
| 981 | with a "scope", introduced by a percent sign. This code is NOT enclosed in #if |
| 982 | HAVE_IPV6 in order that IPv6 addresses are recognized even if IPv6 is not |
| 983 | supported. */ |
| 984 | |
| 985 | if (Ustrchr(address, ':') != NULL) |
| 986 | { |
| 987 | uschar *p = address; |
| 988 | uschar *component[8]; |
| 989 | BOOL ipv4_ends = FALSE; |
| 990 | int ci = 0; |
| 991 | int nulloffset = 0; |
| 992 | int v6count = 8; |
| 993 | int i; |
| 994 | |
| 995 | /* If the address starts with a colon, it will start with two colons. |
| 996 | Just lose the first one, which will leave a null first component. */ |
| 997 | |
| 998 | if (*p == ':') p++; |
| 999 | |
| 1000 | /* Split the address into components separated by colons. The input address |
| 1001 | is supposed to be checked for syntax. There was a case where this was |
| 1002 | overlooked; to guard against that happening again, check here and crash if |
| 1003 | there are too many components. */ |
| 1004 | |
| 1005 | while (*p != 0 && *p != '%') |
| 1006 | { |
| 1007 | int len = Ustrcspn(p, ":%"); |
| 1008 | if (len == 0) nulloffset = ci; |
| 1009 | if (ci > 7) log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
| 1010 | "Internal error: invalid IPv6 address \"%s\" passed to host_aton()", |
| 1011 | address); |
| 1012 | component[ci++] = p; |
| 1013 | p += len; |
| 1014 | if (*p == ':') p++; |
| 1015 | } |
| 1016 | |
| 1017 | /* If the final component contains a dot, it is a trailing v4 address. |
| 1018 | As the syntax is known to be checked, just set up for a trailing |
| 1019 | v4 address and restrict the v6 part to 6 components. */ |
| 1020 | |
| 1021 | if (Ustrchr(component[ci-1], '.') != NULL) |
| 1022 | { |
| 1023 | address = component[--ci]; |
| 1024 | ipv4_ends = TRUE; |
| 1025 | v4offset = 3; |
| 1026 | v6count = 6; |
| 1027 | } |
| 1028 | |
| 1029 | /* If there are fewer than 6 or 8 components, we have to insert some |
| 1030 | more empty ones in the middle. */ |
| 1031 | |
| 1032 | if (ci < v6count) |
| 1033 | { |
| 1034 | int insert_count = v6count - ci; |
| 1035 | for (i = v6count-1; i > nulloffset + insert_count; i--) |
| 1036 | component[i] = component[i - insert_count]; |
| 1037 | while (i > nulloffset) component[i--] = US""; |
| 1038 | } |
| 1039 | |
| 1040 | /* Now turn the components into binary in pairs and bung them |
| 1041 | into the vector of ints. */ |
| 1042 | |
| 1043 | for (i = 0; i < v6count; i += 2) |
| 1044 | bin[i/2] = (Ustrtol(component[i], NULL, 16) << 16) + |
| 1045 | Ustrtol(component[i+1], NULL, 16); |
| 1046 | |
| 1047 | /* If there was no terminating v4 component, we are done. */ |
| 1048 | |
| 1049 | if (!ipv4_ends) return 4; |
| 1050 | } |
| 1051 | |
| 1052 | /* Handle IPv4 address */ |
| 1053 | |
| 1054 | (void)sscanf(CS address, "%d.%d.%d.%d", x, x+1, x+2, x+3); |
| 1055 | bin[v4offset] = (x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3]; |
| 1056 | return v4offset+1; |
| 1057 | } |
| 1058 | |
| 1059 | |
| 1060 | /************************************************* |
| 1061 | * Apply mask to an IP address * |
| 1062 | *************************************************/ |
| 1063 | |
| 1064 | /* Mask an address held in 1 or 4 ints, with the ms bit in the ms bit of the |
| 1065 | first int, etc. |
| 1066 | |
| 1067 | Arguments: |
| 1068 | count the number of ints |
| 1069 | binary points to the ints to be masked |
| 1070 | mask the count of ms bits to leave, or -1 if no masking |
| 1071 | |
| 1072 | Returns: nothing |
| 1073 | */ |
| 1074 | |
| 1075 | void |
| 1076 | host_mask(int count, int *binary, int mask) |
| 1077 | { |
| 1078 | int i; |
| 1079 | if (mask < 0) mask = 99999; |
| 1080 | for (i = 0; i < count; i++) |
| 1081 | { |
| 1082 | int wordmask; |
| 1083 | if (mask == 0) wordmask = 0; |
| 1084 | else if (mask < 32) |
| 1085 | { |
| 1086 | wordmask = (-1) << (32 - mask); |
| 1087 | mask = 0; |
| 1088 | } |
| 1089 | else |
| 1090 | { |
| 1091 | wordmask = -1; |
| 1092 | mask -= 32; |
| 1093 | } |
| 1094 | binary[i] &= wordmask; |
| 1095 | } |
| 1096 | } |
| 1097 | |
| 1098 | |
| 1099 | |
| 1100 | |
| 1101 | /************************************************* |
| 1102 | * Convert masked IP address in ints to text * |
| 1103 | *************************************************/ |
| 1104 | |
| 1105 | /* We can't use host_ntoa() because it assumes the binary values are in network |
| 1106 | byte order, and these are the result of host_aton(), which puts them in ints in |
| 1107 | host byte order. Also, we really want IPv6 addresses to be in a canonical |
| 1108 | format, so we output them with no abbreviation. In a number of cases we can't |
| 1109 | use the normal colon separator in them because it terminates keys in lsearch |
| 1110 | files, so we want to use dot instead. There's an argument that specifies what |
| 1111 | to use for IPv6 addresses. |
| 1112 | |
| 1113 | Arguments: |
| 1114 | count 1 or 4 (number of ints) |
| 1115 | binary points to the ints |
| 1116 | mask mask value; if < 0 don't add to result |
| 1117 | buffer big enough to hold the result |
| 1118 | sep component separator character for IPv6 addresses |
| 1119 | |
| 1120 | Returns: the number of characters placed in buffer, not counting |
| 1121 | the final nul. |
| 1122 | */ |
| 1123 | |
| 1124 | int |
| 1125 | host_nmtoa(int count, int *binary, int mask, uschar *buffer, int sep) |
| 1126 | { |
| 1127 | int i, j; |
| 1128 | uschar *tt = buffer; |
| 1129 | |
| 1130 | if (count == 1) |
| 1131 | { |
| 1132 | j = binary[0]; |
| 1133 | for (i = 24; i >= 0; i -= 8) |
| 1134 | { |
| 1135 | sprintf(CS tt, "%d.", (j >> i) & 255); |
| 1136 | while (*tt) tt++; |
| 1137 | } |
| 1138 | } |
| 1139 | else |
| 1140 | { |
| 1141 | for (i = 0; i < 4; i++) |
| 1142 | { |
| 1143 | j = binary[i]; |
| 1144 | sprintf(CS tt, "%04x%c%04x%c", (j >> 16) & 0xffff, sep, j & 0xffff, sep); |
| 1145 | while (*tt) tt++; |
| 1146 | } |
| 1147 | } |
| 1148 | |
| 1149 | tt--; /* lose final separator */ |
| 1150 | |
| 1151 | if (mask < 0) |
| 1152 | *tt = 0; |
| 1153 | else |
| 1154 | { |
| 1155 | sprintf(CS tt, "/%d", mask); |
| 1156 | while (*tt) tt++; |
| 1157 | } |
| 1158 | |
| 1159 | return tt - buffer; |
| 1160 | } |
| 1161 | |
| 1162 | |
| 1163 | |
| 1164 | /************************************************* |
| 1165 | * Check port for tls_on_connect * |
| 1166 | *************************************************/ |
| 1167 | |
| 1168 | /* This function checks whether a given incoming port is configured for tls- |
| 1169 | on-connect. It is called from the daemon and from inetd handling. If the global |
| 1170 | option tls_on_connect is already set, all ports operate this way. Otherwise, we |
| 1171 | check the tls_on_connect_ports option for a list of ports. |
| 1172 | |
| 1173 | Argument: a port number |
| 1174 | Returns: TRUE or FALSE |
| 1175 | */ |
| 1176 | |
| 1177 | BOOL |
| 1178 | host_is_tls_on_connect_port(int port) |
| 1179 | { |
| 1180 | int sep = 0; |
| 1181 | uschar buffer[32]; |
| 1182 | uschar *list = tls_in.on_connect_ports; |
| 1183 | uschar *s; |
| 1184 | uschar *end; |
| 1185 | |
| 1186 | if (tls_in.on_connect) return TRUE; |
| 1187 | |
| 1188 | while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer)))) |
| 1189 | if (Ustrtol(s, &end, 10) == port) |
| 1190 | return TRUE; |
| 1191 | |
| 1192 | return FALSE; |
| 1193 | } |
| 1194 | |
| 1195 | |
| 1196 | |
| 1197 | /************************************************* |
| 1198 | * Check whether host is in a network * |
| 1199 | *************************************************/ |
| 1200 | |
| 1201 | /* This function checks whether a given IP address matches a pattern that |
| 1202 | represents either a single host, or a network (using CIDR notation). The caller |
| 1203 | of this function must check the syntax of the arguments before calling it. |
| 1204 | |
| 1205 | Arguments: |
| 1206 | host string representation of the ip-address to check |
| 1207 | net string representation of the network, with optional CIDR mask |
| 1208 | maskoffset offset to the / that introduces the mask in the key |
| 1209 | zero if there is no mask |
| 1210 | |
| 1211 | Returns: |
| 1212 | TRUE the host is inside the network |
| 1213 | FALSE the host is NOT inside the network |
| 1214 | */ |
| 1215 | |
| 1216 | BOOL |
| 1217 | host_is_in_net(uschar *host, uschar *net, int maskoffset) |
| 1218 | { |
| 1219 | int i; |
| 1220 | int address[4]; |
| 1221 | int incoming[4]; |
| 1222 | int mlen; |
| 1223 | int size = host_aton(net, address); |
| 1224 | int insize; |
| 1225 | |
| 1226 | /* No mask => all bits to be checked */ |
| 1227 | |
| 1228 | if (maskoffset == 0) mlen = 99999; /* Big number */ |
| 1229 | else mlen = Uatoi(net + maskoffset + 1); |
| 1230 | |
| 1231 | /* Convert the incoming address to binary. */ |
| 1232 | |
| 1233 | insize = host_aton(host, incoming); |
| 1234 | |
| 1235 | /* Convert IPv4 addresses given in IPv6 compatible mode, which represent |
| 1236 | connections from IPv4 hosts to IPv6 hosts, that is, addresses of the form |
| 1237 | ::ffff:<v4address>, to IPv4 format. */ |
| 1238 | |
| 1239 | if (insize == 4 && incoming[0] == 0 && incoming[1] == 0 && |
| 1240 | incoming[2] == 0xffff) |
| 1241 | { |
| 1242 | insize = 1; |
| 1243 | incoming[0] = incoming[3]; |
| 1244 | } |
| 1245 | |
| 1246 | /* No match if the sizes don't agree. */ |
| 1247 | |
| 1248 | if (insize != size) return FALSE; |
| 1249 | |
| 1250 | /* Else do the masked comparison. */ |
| 1251 | |
| 1252 | for (i = 0; i < size; i++) |
| 1253 | { |
| 1254 | int mask; |
| 1255 | if (mlen == 0) mask = 0; |
| 1256 | else if (mlen < 32) |
| 1257 | { |
| 1258 | mask = (-1) << (32 - mlen); |
| 1259 | mlen = 0; |
| 1260 | } |
| 1261 | else |
| 1262 | { |
| 1263 | mask = -1; |
| 1264 | mlen -= 32; |
| 1265 | } |
| 1266 | if ((incoming[i] & mask) != (address[i] & mask)) return FALSE; |
| 1267 | } |
| 1268 | |
| 1269 | return TRUE; |
| 1270 | } |
| 1271 | |
| 1272 | |
| 1273 | |
| 1274 | /************************************************* |
| 1275 | * Scan host list for local hosts * |
| 1276 | *************************************************/ |
| 1277 | |
| 1278 | /* Scan through a chain of addresses and check whether any of them is the |
| 1279 | address of an interface on the local machine. If so, remove that address and |
| 1280 | any previous ones with the same MX value, and all subsequent ones (which will |
| 1281 | have greater or equal MX values) from the chain. Note: marking them as unusable |
| 1282 | is NOT the right thing to do because it causes the hosts not to be used for |
| 1283 | other domains, for which they may well be correct. |
| 1284 | |
| 1285 | The hosts may be part of a longer chain; we only process those between the |
| 1286 | initial pointer and the "last" pointer. |
| 1287 | |
| 1288 | There is also a list of "pseudo-local" host names which are checked against the |
| 1289 | host names. Any match causes that host item to be treated the same as one which |
| 1290 | matches a local IP address. |
| 1291 | |
| 1292 | If the very first host is a local host, then all MX records had a precedence |
| 1293 | greater than or equal to that of the local host. Either there's a problem in |
| 1294 | the DNS, or an apparently remote name turned out to be an abbreviation for the |
| 1295 | local host. Give a specific return code, and let the caller decide what to do. |
| 1296 | Otherwise, give a success code if at least one host address has been found. |
| 1297 | |
| 1298 | Arguments: |
| 1299 | host pointer to the first host in the chain |
| 1300 | lastptr pointer to pointer to the last host in the chain (may be updated) |
| 1301 | removed if not NULL, set TRUE if some local addresses were removed |
| 1302 | from the list |
| 1303 | |
| 1304 | Returns: |
| 1305 | HOST_FOUND if there is at least one host with an IP address on the chain |
| 1306 | and an MX value less than any MX value associated with the |
| 1307 | local host |
| 1308 | HOST_FOUND_LOCAL if a local host is among the lowest-numbered MX hosts; when |
| 1309 | the host addresses were obtained from A records or |
| 1310 | gethostbyname(), the MX values are set to -1. |
| 1311 | HOST_FIND_FAILED if no valid hosts with set IP addresses were found |
| 1312 | */ |
| 1313 | |
| 1314 | int |
| 1315 | host_scan_for_local_hosts(host_item *host, host_item **lastptr, BOOL *removed) |
| 1316 | { |
| 1317 | int yield = HOST_FIND_FAILED; |
| 1318 | host_item *last = *lastptr; |
| 1319 | host_item *prev = NULL; |
| 1320 | host_item *h; |
| 1321 | |
| 1322 | if (removed != NULL) *removed = FALSE; |
| 1323 | |
| 1324 | if (local_interface_data == NULL) local_interface_data = host_find_interfaces(); |
| 1325 | |
| 1326 | for (h = host; h != last->next; h = h->next) |
| 1327 | { |
| 1328 | #ifndef STAND_ALONE |
| 1329 | if (hosts_treat_as_local != NULL) |
| 1330 | { |
| 1331 | int rc; |
| 1332 | uschar *save = deliver_domain; |
| 1333 | deliver_domain = h->name; /* set $domain */ |
| 1334 | rc = match_isinlist(string_copylc(h->name), &hosts_treat_as_local, 0, |
| 1335 | &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL); |
| 1336 | deliver_domain = save; |
| 1337 | if (rc == OK) goto FOUND_LOCAL; |
| 1338 | } |
| 1339 | #endif |
| 1340 | |
| 1341 | /* It seems that on many operating systems, 0.0.0.0 is treated as a synonym |
| 1342 | for 127.0.0.1 and refers to the local host. We therefore force it always to |
| 1343 | be treated as local. */ |
| 1344 | |
| 1345 | if (h->address != NULL) |
| 1346 | { |
| 1347 | ip_address_item *ip; |
| 1348 | if (Ustrcmp(h->address, "0.0.0.0") == 0) goto FOUND_LOCAL; |
| 1349 | for (ip = local_interface_data; ip != NULL; ip = ip->next) |
| 1350 | if (Ustrcmp(h->address, ip->address) == 0) goto FOUND_LOCAL; |
| 1351 | yield = HOST_FOUND; /* At least one remote address has been found */ |
| 1352 | } |
| 1353 | |
| 1354 | /* Update prev to point to the last host item before any that have |
| 1355 | the same MX value as the one we have just considered. */ |
| 1356 | |
| 1357 | if (h->next == NULL || h->next->mx != h->mx) prev = h; |
| 1358 | } |
| 1359 | |
| 1360 | return yield; /* No local hosts found: return HOST_FOUND or HOST_FIND_FAILED */ |
| 1361 | |
| 1362 | /* A host whose IP address matches a local IP address, or whose name matches |
| 1363 | something in hosts_treat_as_local has been found. */ |
| 1364 | |
| 1365 | FOUND_LOCAL: |
| 1366 | |
| 1367 | if (prev == NULL) |
| 1368 | { |
| 1369 | HDEBUG(D_host_lookup) debug_printf((h->mx >= 0)? |
| 1370 | "local host has lowest MX\n" : |
| 1371 | "local host found for non-MX address\n"); |
| 1372 | return HOST_FOUND_LOCAL; |
| 1373 | } |
| 1374 | |
| 1375 | HDEBUG(D_host_lookup) |
| 1376 | { |
| 1377 | debug_printf("local host in host list - removed hosts:\n"); |
| 1378 | for (h = prev->next; h != last->next; h = h->next) |
| 1379 | debug_printf(" %s %s %d\n", h->name, h->address, h->mx); |
| 1380 | } |
| 1381 | |
| 1382 | if (removed != NULL) *removed = TRUE; |
| 1383 | prev->next = last->next; |
| 1384 | *lastptr = prev; |
| 1385 | return yield; |
| 1386 | } |
| 1387 | |
| 1388 | |
| 1389 | |
| 1390 | |
| 1391 | /************************************************* |
| 1392 | * Remove duplicate IPs in host list * |
| 1393 | *************************************************/ |
| 1394 | |
| 1395 | /* You would think that administrators could set up their DNS records so that |
| 1396 | one ended up with a list of unique IP addresses after looking up A or MX |
| 1397 | records, but apparently duplication is common. So we scan such lists and |
| 1398 | remove the later duplicates. Note that we may get lists in which some host |
| 1399 | addresses are not set. |
| 1400 | |
| 1401 | Arguments: |
| 1402 | host pointer to the first host in the chain |
| 1403 | lastptr pointer to pointer to the last host in the chain (may be updated) |
| 1404 | |
| 1405 | Returns: nothing |
| 1406 | */ |
| 1407 | |
| 1408 | static void |
| 1409 | host_remove_duplicates(host_item *host, host_item **lastptr) |
| 1410 | { |
| 1411 | while (host != *lastptr) |
| 1412 | { |
| 1413 | if (host->address != NULL) |
| 1414 | { |
| 1415 | host_item *h = host; |
| 1416 | while (h != *lastptr) |
| 1417 | { |
| 1418 | if (h->next->address != NULL && |
| 1419 | Ustrcmp(h->next->address, host->address) == 0) |
| 1420 | { |
| 1421 | DEBUG(D_host_lookup) debug_printf("duplicate IP address %s (MX=%d) " |
| 1422 | "removed\n", host->address, h->next->mx); |
| 1423 | if (h->next == *lastptr) *lastptr = h; |
| 1424 | h->next = h->next->next; |
| 1425 | } |
| 1426 | else h = h->next; |
| 1427 | } |
| 1428 | } |
| 1429 | /* If the last item was removed, host may have become == *lastptr */ |
| 1430 | if (host != *lastptr) host = host->next; |
| 1431 | } |
| 1432 | } |
| 1433 | |
| 1434 | |
| 1435 | |
| 1436 | |
| 1437 | /************************************************* |
| 1438 | * Find sender host name by gethostbyaddr() * |
| 1439 | *************************************************/ |
| 1440 | |
| 1441 | /* This used to be the only way it was done, but it turns out that not all |
| 1442 | systems give aliases for calls to gethostbyaddr() - or one of the modern |
| 1443 | equivalents like getipnodebyaddr(). Fortunately, multiple PTR records are rare, |
| 1444 | but they can still exist. This function is now used only when a DNS lookup of |
| 1445 | the IP address fails, in order to give access to /etc/hosts. |
| 1446 | |
| 1447 | Arguments: none |
| 1448 | Returns: OK, DEFER, FAIL |
| 1449 | */ |
| 1450 | |
| 1451 | static int |
| 1452 | host_name_lookup_byaddr(void) |
| 1453 | { |
| 1454 | int len; |
| 1455 | uschar *s, *t; |
| 1456 | struct hostent *hosts; |
| 1457 | struct in_addr addr; |
| 1458 | |
| 1459 | /* Lookup on IPv6 system */ |
| 1460 | |
| 1461 | #if HAVE_IPV6 |
| 1462 | if (Ustrchr(sender_host_address, ':') != NULL) |
| 1463 | { |
| 1464 | struct in6_addr addr6; |
| 1465 | if (inet_pton(AF_INET6, CS sender_host_address, &addr6) != 1) |
| 1466 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an " |
| 1467 | "IPv6 address", sender_host_address); |
| 1468 | #if HAVE_GETIPNODEBYADDR |
| 1469 | hosts = getipnodebyaddr(CS &addr6, sizeof(addr6), AF_INET6, &h_errno); |
| 1470 | #else |
| 1471 | hosts = gethostbyaddr(CS &addr6, sizeof(addr6), AF_INET6); |
| 1472 | #endif |
| 1473 | } |
| 1474 | else |
| 1475 | { |
| 1476 | if (inet_pton(AF_INET, CS sender_host_address, &addr) != 1) |
| 1477 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an " |
| 1478 | "IPv4 address", sender_host_address); |
| 1479 | #if HAVE_GETIPNODEBYADDR |
| 1480 | hosts = getipnodebyaddr(CS &addr, sizeof(addr), AF_INET, &h_errno); |
| 1481 | #else |
| 1482 | hosts = gethostbyaddr(CS &addr, sizeof(addr), AF_INET); |
| 1483 | #endif |
| 1484 | } |
| 1485 | |
| 1486 | /* Do lookup on IPv4 system */ |
| 1487 | |
| 1488 | #else |
| 1489 | addr.s_addr = (S_ADDR_TYPE)inet_addr(CS sender_host_address); |
| 1490 | hosts = gethostbyaddr(CS(&addr), sizeof(addr), AF_INET); |
| 1491 | #endif |
| 1492 | |
| 1493 | /* Failed to look up the host. */ |
| 1494 | |
| 1495 | if (hosts == NULL) |
| 1496 | { |
| 1497 | HDEBUG(D_host_lookup) debug_printf("IP address lookup failed: h_errno=%d\n", |
| 1498 | h_errno); |
| 1499 | return (h_errno == TRY_AGAIN || h_errno == NO_RECOVERY) ? DEFER : FAIL; |
| 1500 | } |
| 1501 | |
| 1502 | /* It seems there are some records in the DNS that yield an empty name. We |
| 1503 | treat this as non-existent. In some operating systems, this is returned as an |
| 1504 | empty string; in others as a single dot. */ |
| 1505 | |
| 1506 | if (hosts->h_name == NULL || hosts->h_name[0] == 0 || hosts->h_name[0] == '.') |
| 1507 | { |
| 1508 | HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an empty name: " |
| 1509 | "treated as non-existent host name\n"); |
| 1510 | return FAIL; |
| 1511 | } |
| 1512 | |
| 1513 | /* Copy and lowercase the name, which is in static storage in many systems. |
| 1514 | Put it in permanent memory. */ |
| 1515 | |
| 1516 | s = (uschar *)hosts->h_name; |
| 1517 | len = Ustrlen(s) + 1; |
| 1518 | t = sender_host_name = store_get_perm(len); |
| 1519 | while (*s != 0) *t++ = tolower(*s++); |
| 1520 | *t = 0; |
| 1521 | |
| 1522 | /* If the host has aliases, build a copy of the alias list */ |
| 1523 | |
| 1524 | if (hosts->h_aliases != NULL) |
| 1525 | { |
| 1526 | int count = 1; |
| 1527 | uschar **aliases, **ptr; |
| 1528 | for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++) count++; |
| 1529 | ptr = sender_host_aliases = store_get_perm(count * sizeof(uschar *)); |
| 1530 | for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++) |
| 1531 | { |
| 1532 | uschar *s = *aliases; |
| 1533 | int len = Ustrlen(s) + 1; |
| 1534 | uschar *t = *ptr++ = store_get_perm(len); |
| 1535 | while (*s != 0) *t++ = tolower(*s++); |
| 1536 | *t = 0; |
| 1537 | } |
| 1538 | *ptr = NULL; |
| 1539 | } |
| 1540 | |
| 1541 | return OK; |
| 1542 | } |
| 1543 | |
| 1544 | |
| 1545 | |
| 1546 | /************************************************* |
| 1547 | * Find host name for incoming call * |
| 1548 | *************************************************/ |
| 1549 | |
| 1550 | /* Put the name in permanent store, pointed to by sender_host_name. We also set |
| 1551 | up a list of alias names, pointed to by sender_host_alias. The list is |
| 1552 | NULL-terminated. The incoming address is in sender_host_address, either in |
| 1553 | dotted-quad form for IPv4 or in colon-separated form for IPv6. |
| 1554 | |
| 1555 | This function does a thorough check that the names it finds point back to the |
| 1556 | incoming IP address. Any that do not are discarded. Note that this is relied on |
| 1557 | by the ACL reverse_host_lookup check. |
| 1558 | |
| 1559 | On some systems, get{host,ipnode}byaddr() appears to do this internally, but |
| 1560 | this it not universally true. Also, for release 4.30, this function was changed |
| 1561 | to do a direct DNS lookup first, by default[1], because it turns out that that |
| 1562 | is the only guaranteed way to find all the aliases on some systems. My |
| 1563 | experiments indicate that Solaris gethostbyaddr() gives the aliases for but |
| 1564 | Linux does not. |
| 1565 | |
| 1566 | [1] The actual order is controlled by the host_lookup_order option. |
| 1567 | |
| 1568 | Arguments: none |
| 1569 | Returns: OK on success, the answer being placed in the global variable |
| 1570 | sender_host_name, with any aliases in a list hung off |
| 1571 | sender_host_aliases |
| 1572 | FAIL if no host name can be found |
| 1573 | DEFER if a temporary error was encountered |
| 1574 | |
| 1575 | The variable host_lookup_msg is set to an empty string on sucess, or to a |
| 1576 | reason for the failure otherwise, in a form suitable for tagging onto an error |
| 1577 | message, and also host_lookup_failed is set TRUE if the lookup failed. If there |
| 1578 | was a defer, host_lookup_deferred is set TRUE. |
| 1579 | |
| 1580 | Any dynamically constructed string for host_lookup_msg must be in permanent |
| 1581 | store, because it might be used for several incoming messages on the same SMTP |
| 1582 | connection. */ |
| 1583 | |
| 1584 | int |
| 1585 | host_name_lookup(void) |
| 1586 | { |
| 1587 | int old_pool, rc; |
| 1588 | int sep = 0; |
| 1589 | uschar *hname, *save_hostname; |
| 1590 | uschar **aliases; |
| 1591 | uschar buffer[256]; |
| 1592 | uschar *ordername; |
| 1593 | uschar *list = host_lookup_order; |
| 1594 | dns_record *rr; |
| 1595 | dns_answer dnsa; |
| 1596 | dns_scan dnss; |
| 1597 | |
| 1598 | sender_host_dnssec = host_lookup_deferred = host_lookup_failed = FALSE; |
| 1599 | |
| 1600 | HDEBUG(D_host_lookup) |
| 1601 | debug_printf("looking up host name for %s\n", sender_host_address); |
| 1602 | |
| 1603 | /* For testing the case when a lookup does not complete, we have a special |
| 1604 | reserved IP address. */ |
| 1605 | |
| 1606 | if (running_in_test_harness && |
| 1607 | Ustrcmp(sender_host_address, "99.99.99.99") == 0) |
| 1608 | { |
| 1609 | HDEBUG(D_host_lookup) |
| 1610 | debug_printf("Test harness: host name lookup returns DEFER\n"); |
| 1611 | host_lookup_deferred = TRUE; |
| 1612 | return DEFER; |
| 1613 | } |
| 1614 | |
| 1615 | /* Do lookups directly in the DNS or via gethostbyaddr() (or equivalent), in |
| 1616 | the order specified by the host_lookup_order option. */ |
| 1617 | |
| 1618 | while ((ordername = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) |
| 1619 | != NULL) |
| 1620 | { |
| 1621 | if (strcmpic(ordername, US"bydns") == 0) |
| 1622 | { |
| 1623 | dns_init(FALSE, FALSE, FALSE); /* dnssec ctrl by dns_dnssec_ok glbl */ |
| 1624 | dns_build_reverse(sender_host_address, buffer); |
| 1625 | rc = dns_lookup(&dnsa, buffer, T_PTR, NULL); |
| 1626 | |
| 1627 | /* The first record we come across is used for the name; others are |
| 1628 | considered to be aliases. We have to scan twice, in order to find out the |
| 1629 | number of aliases. However, if all the names are empty, we will behave as |
| 1630 | if failure. (PTR records that yield empty names have been encountered in |
| 1631 | the DNS.) */ |
| 1632 | |
| 1633 | if (rc == DNS_SUCCEED) |
| 1634 | { |
| 1635 | uschar **aptr = NULL; |
| 1636 | int ssize = 264; |
| 1637 | int count = 0; |
| 1638 | int old_pool = store_pool; |
| 1639 | |
| 1640 | /* Ideally we'd check DNSSEC both forward and reverse, but we use the |
| 1641 | gethost* routines for forward, so can't do that unless/until we rewrite. */ |
| 1642 | sender_host_dnssec = dns_is_secure(&dnsa); |
| 1643 | DEBUG(D_dns) |
| 1644 | debug_printf("Reverse DNS security status: %s\n", |
| 1645 | sender_host_dnssec ? "DNSSEC verified (AD)" : "unverified"); |
| 1646 | |
| 1647 | store_pool = POOL_PERM; /* Save names in permanent storage */ |
| 1648 | |
| 1649 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 1650 | rr != NULL; |
| 1651 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 1652 | { |
| 1653 | if (rr->type == T_PTR) count++; |
| 1654 | } |
| 1655 | |
| 1656 | /* Get store for the list of aliases. For compatibility with |
| 1657 | gethostbyaddr, we make an empty list if there are none. */ |
| 1658 | |
| 1659 | aptr = sender_host_aliases = store_get(count * sizeof(uschar *)); |
| 1660 | |
| 1661 | /* Re-scan and extract the names */ |
| 1662 | |
| 1663 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 1664 | rr != NULL; |
| 1665 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 1666 | { |
| 1667 | uschar *s = NULL; |
| 1668 | if (rr->type != T_PTR) continue; |
| 1669 | s = store_get(ssize); |
| 1670 | |
| 1671 | /* If an overlong response was received, the data will have been |
| 1672 | truncated and dn_expand may fail. */ |
| 1673 | |
| 1674 | if (dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, |
| 1675 | (uschar *)(rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0) |
| 1676 | { |
| 1677 | log_write(0, LOG_MAIN, "host name alias list truncated for %s", |
| 1678 | sender_host_address); |
| 1679 | break; |
| 1680 | } |
| 1681 | |
| 1682 | store_reset(s + Ustrlen(s) + 1); |
| 1683 | if (s[0] == 0) |
| 1684 | { |
| 1685 | HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an " |
| 1686 | "empty name: treated as non-existent host name\n"); |
| 1687 | continue; |
| 1688 | } |
| 1689 | if (sender_host_name == NULL) sender_host_name = s; |
| 1690 | else *aptr++ = s; |
| 1691 | while (*s != 0) { *s = tolower(*s); s++; } |
| 1692 | } |
| 1693 | |
| 1694 | *aptr = NULL; /* End of alias list */ |
| 1695 | store_pool = old_pool; /* Reset store pool */ |
| 1696 | |
| 1697 | /* If we've found a names, break out of the "order" loop */ |
| 1698 | |
| 1699 | if (sender_host_name != NULL) break; |
| 1700 | } |
| 1701 | |
| 1702 | /* If the DNS lookup deferred, we must also defer. */ |
| 1703 | |
| 1704 | if (rc == DNS_AGAIN) |
| 1705 | { |
| 1706 | HDEBUG(D_host_lookup) |
| 1707 | debug_printf("IP address PTR lookup gave temporary error\n"); |
| 1708 | host_lookup_deferred = TRUE; |
| 1709 | return DEFER; |
| 1710 | } |
| 1711 | } |
| 1712 | |
| 1713 | /* Do a lookup using gethostbyaddr() - or equivalent */ |
| 1714 | |
| 1715 | else if (strcmpic(ordername, US"byaddr") == 0) |
| 1716 | { |
| 1717 | HDEBUG(D_host_lookup) |
| 1718 | debug_printf("IP address lookup using gethostbyaddr()\n"); |
| 1719 | rc = host_name_lookup_byaddr(); |
| 1720 | if (rc == DEFER) |
| 1721 | { |
| 1722 | host_lookup_deferred = TRUE; |
| 1723 | return rc; /* Can't carry on */ |
| 1724 | } |
| 1725 | if (rc == OK) break; /* Found a name */ |
| 1726 | } |
| 1727 | } /* Loop for bydns/byaddr scanning */ |
| 1728 | |
| 1729 | /* If we have failed to find a name, return FAIL and log when required. |
| 1730 | NB host_lookup_msg must be in permanent store. */ |
| 1731 | |
| 1732 | if (sender_host_name == NULL) |
| 1733 | { |
| 1734 | if (host_checking || !log_testing_mode) |
| 1735 | log_write(L_host_lookup_failed, LOG_MAIN, "no host name found for IP " |
| 1736 | "address %s", sender_host_address); |
| 1737 | host_lookup_msg = US" (failed to find host name from IP address)"; |
| 1738 | host_lookup_failed = TRUE; |
| 1739 | return FAIL; |
| 1740 | } |
| 1741 | |
| 1742 | HDEBUG(D_host_lookup) |
| 1743 | { |
| 1744 | uschar **aliases = sender_host_aliases; |
| 1745 | debug_printf("IP address lookup yielded %s\n", sender_host_name); |
| 1746 | while (*aliases != NULL) debug_printf(" alias %s\n", *aliases++); |
| 1747 | } |
| 1748 | |
| 1749 | /* We need to verify that a forward lookup on the name we found does indeed |
| 1750 | correspond to the address. This is for security: in principle a malefactor who |
| 1751 | happened to own a reverse zone could set it to point to any names at all. |
| 1752 | |
| 1753 | This code was present in versions of Exim before 3.20. At that point I took it |
| 1754 | out because I thought that gethostbyaddr() did the check anyway. It turns out |
| 1755 | that this isn't always the case, so it's coming back in at 4.01. This version |
| 1756 | is actually better, because it also checks aliases. |
| 1757 | |
| 1758 | The code was made more robust at release 4.21. Prior to that, it accepted all |
| 1759 | the names if any of them had the correct IP address. Now the code checks all |
| 1760 | the names, and accepts only those that have the correct IP address. */ |
| 1761 | |
| 1762 | save_hostname = sender_host_name; /* Save for error messages */ |
| 1763 | aliases = sender_host_aliases; |
| 1764 | for (hname = sender_host_name; hname != NULL; hname = *aliases++) |
| 1765 | { |
| 1766 | int rc; |
| 1767 | BOOL ok = FALSE; |
| 1768 | host_item h; |
| 1769 | h.next = NULL; |
| 1770 | h.name = hname; |
| 1771 | h.mx = MX_NONE; |
| 1772 | h.address = NULL; |
| 1773 | |
| 1774 | /* When called with the last argument FALSE, host_find_byname() won't return |
| 1775 | HOST_FOUND_LOCAL. If the incoming address is an IPv4 address expressed in |
| 1776 | IPv6 format, we must compare the IPv4 part to any IPv4 addresses. */ |
| 1777 | |
| 1778 | if ((rc = host_find_byname(&h, NULL, 0, NULL, FALSE)) == HOST_FOUND) |
| 1779 | { |
| 1780 | host_item *hh; |
| 1781 | HDEBUG(D_host_lookup) debug_printf("checking addresses for %s\n", hname); |
| 1782 | for (hh = &h; hh != NULL; hh = hh->next) |
| 1783 | { |
| 1784 | if (host_is_in_net(hh->address, sender_host_address, 0)) |
| 1785 | { |
| 1786 | HDEBUG(D_host_lookup) debug_printf(" %s OK\n", hh->address); |
| 1787 | ok = TRUE; |
| 1788 | break; |
| 1789 | } |
| 1790 | else |
| 1791 | { |
| 1792 | HDEBUG(D_host_lookup) debug_printf(" %s\n", hh->address); |
| 1793 | } |
| 1794 | } |
| 1795 | if (!ok) HDEBUG(D_host_lookup) |
| 1796 | debug_printf("no IP address for %s matched %s\n", hname, |
| 1797 | sender_host_address); |
| 1798 | } |
| 1799 | else if (rc == HOST_FIND_AGAIN) |
| 1800 | { |
| 1801 | HDEBUG(D_host_lookup) debug_printf("temporary error for host name lookup\n"); |
| 1802 | host_lookup_deferred = TRUE; |
| 1803 | sender_host_name = NULL; |
| 1804 | return DEFER; |
| 1805 | } |
| 1806 | else |
| 1807 | { |
| 1808 | HDEBUG(D_host_lookup) debug_printf("no IP addresses found for %s\n", hname); |
| 1809 | } |
| 1810 | |
| 1811 | /* If this name is no good, and it's the sender name, set it null pro tem; |
| 1812 | if it's an alias, just remove it from the list. */ |
| 1813 | |
| 1814 | if (!ok) |
| 1815 | { |
| 1816 | if (hname == sender_host_name) sender_host_name = NULL; else |
| 1817 | { |
| 1818 | uschar **a; /* Don't amalgamate - some */ |
| 1819 | a = --aliases; /* compilers grumble */ |
| 1820 | while (*a != NULL) { *a = a[1]; a++; } |
| 1821 | } |
| 1822 | } |
| 1823 | } |
| 1824 | |
| 1825 | /* If sender_host_name == NULL, it means we didn't like the name. Replace |
| 1826 | it with the first alias, if there is one. */ |
| 1827 | |
| 1828 | if (sender_host_name == NULL && *sender_host_aliases != NULL) |
| 1829 | sender_host_name = *sender_host_aliases++; |
| 1830 | |
| 1831 | /* If we now have a main name, all is well. */ |
| 1832 | |
| 1833 | if (sender_host_name != NULL) return OK; |
| 1834 | |
| 1835 | /* We have failed to find an address that matches. */ |
| 1836 | |
| 1837 | HDEBUG(D_host_lookup) |
| 1838 | debug_printf("%s does not match any IP address for %s\n", |
| 1839 | sender_host_address, save_hostname); |
| 1840 | |
| 1841 | /* This message must be in permanent store */ |
| 1842 | |
| 1843 | old_pool = store_pool; |
| 1844 | store_pool = POOL_PERM; |
| 1845 | host_lookup_msg = string_sprintf(" (%s does not match any IP address for %s)", |
| 1846 | sender_host_address, save_hostname); |
| 1847 | store_pool = old_pool; |
| 1848 | host_lookup_failed = TRUE; |
| 1849 | return FAIL; |
| 1850 | } |
| 1851 | |
| 1852 | |
| 1853 | |
| 1854 | |
| 1855 | /************************************************* |
| 1856 | * Find IP address(es) for host by name * |
| 1857 | *************************************************/ |
| 1858 | |
| 1859 | /* The input is a host_item structure with the name filled in and the address |
| 1860 | field set to NULL. We use gethostbyname() or getipnodebyname() or |
| 1861 | gethostbyname2(), as appropriate. Of course, these functions may use the DNS, |
| 1862 | but they do not do MX processing. It appears, however, that in some systems the |
| 1863 | current setting of resolver options is used when one of these functions calls |
| 1864 | the resolver. For this reason, we call dns_init() at the start, with arguments |
| 1865 | influenced by bits in "flags", just as we do for host_find_bydns(). |
| 1866 | |
| 1867 | The second argument provides a host list (usually an IP list) of hosts to |
| 1868 | ignore. This makes it possible to ignore IPv6 link-local addresses or loopback |
| 1869 | addresses in unreasonable places. |
| 1870 | |
| 1871 | The lookup may result in a change of name. For compatibility with the dns |
| 1872 | lookup, return this via fully_qualified_name as well as updating the host item. |
| 1873 | The lookup may also yield more than one IP address, in which case chain on |
| 1874 | subsequent host_item structures. |
| 1875 | |
| 1876 | Arguments: |
| 1877 | host a host item with the name and MX filled in; |
| 1878 | the address is to be filled in; |
| 1879 | multiple IP addresses cause other host items to be |
| 1880 | chained on. |
| 1881 | ignore_target_hosts a list of hosts to ignore |
| 1882 | flags HOST_FIND_QUALIFY_SINGLE ) passed to |
| 1883 | HOST_FIND_SEARCH_PARENTS ) dns_init() |
| 1884 | fully_qualified_name if not NULL, set to point to host name for |
| 1885 | compatibility with host_find_bydns |
| 1886 | local_host_check TRUE if a check for the local host is wanted |
| 1887 | |
| 1888 | Returns: HOST_FIND_FAILED Failed to find the host or domain |
| 1889 | HOST_FIND_AGAIN Try again later |
| 1890 | HOST_FOUND Host found - data filled in |
| 1891 | HOST_FOUND_LOCAL Host found and is the local host |
| 1892 | */ |
| 1893 | |
| 1894 | int |
| 1895 | host_find_byname(host_item *host, uschar *ignore_target_hosts, int flags, |
| 1896 | uschar **fully_qualified_name, BOOL local_host_check) |
| 1897 | { |
| 1898 | int i, yield, times; |
| 1899 | uschar **addrlist; |
| 1900 | host_item *last = NULL; |
| 1901 | BOOL temp_error = FALSE; |
| 1902 | #if HAVE_IPV6 |
| 1903 | int af; |
| 1904 | #endif |
| 1905 | |
| 1906 | /* If we are in the test harness, a name ending in .test.again.dns always |
| 1907 | forces a temporary error response, unless the name is in |
| 1908 | dns_again_means_nonexist. */ |
| 1909 | |
| 1910 | if (running_in_test_harness) |
| 1911 | { |
| 1912 | uschar *endname = host->name + Ustrlen(host->name); |
| 1913 | if (Ustrcmp(endname - 14, "test.again.dns") == 0) goto RETURN_AGAIN; |
| 1914 | } |
| 1915 | |
| 1916 | /* Make sure DNS options are set as required. This appears to be necessary in |
| 1917 | some circumstances when the get..byname() function actually calls the DNS. */ |
| 1918 | |
| 1919 | dns_init((flags & HOST_FIND_QUALIFY_SINGLE) != 0, |
| 1920 | (flags & HOST_FIND_SEARCH_PARENTS) != 0, |
| 1921 | FALSE); /*XXX dnssec? */ |
| 1922 | |
| 1923 | /* In an IPv6 world, unless IPv6 has been disabled, we need to scan for both |
| 1924 | kinds of address, so go round the loop twice. Note that we have ensured that |
| 1925 | AF_INET6 is defined even in an IPv4 world, which makes for slightly tidier |
| 1926 | code. However, if dns_ipv4_lookup matches the domain, we also just do IPv4 |
| 1927 | lookups here (except when testing standalone). */ |
| 1928 | |
| 1929 | #if HAVE_IPV6 |
| 1930 | #ifdef STAND_ALONE |
| 1931 | if (disable_ipv6) |
| 1932 | #else |
| 1933 | if (disable_ipv6 || |
| 1934 | (dns_ipv4_lookup != NULL && |
| 1935 | match_isinlist(host->name, &dns_ipv4_lookup, 0, NULL, NULL, MCL_DOMAIN, |
| 1936 | TRUE, NULL) == OK)) |
| 1937 | #endif |
| 1938 | |
| 1939 | { af = AF_INET; times = 1; } |
| 1940 | else |
| 1941 | { af = AF_INET6; times = 2; } |
| 1942 | |
| 1943 | /* No IPv6 support */ |
| 1944 | |
| 1945 | #else /* HAVE_IPV6 */ |
| 1946 | times = 1; |
| 1947 | #endif /* HAVE_IPV6 */ |
| 1948 | |
| 1949 | /* Initialize the flag that gets set for DNS syntax check errors, so that the |
| 1950 | interface to this function can be similar to host_find_bydns. */ |
| 1951 | |
| 1952 | host_find_failed_syntax = FALSE; |
| 1953 | |
| 1954 | /* Loop to look up both kinds of address in an IPv6 world */ |
| 1955 | |
| 1956 | for (i = 1; i <= times; |
| 1957 | #if HAVE_IPV6 |
| 1958 | af = AF_INET, /* If 2 passes, IPv4 on the second */ |
| 1959 | #endif |
| 1960 | i++) |
| 1961 | { |
| 1962 | BOOL ipv4_addr; |
| 1963 | int error_num = 0; |
| 1964 | struct hostent *hostdata; |
| 1965 | |
| 1966 | #ifdef STAND_ALONE |
| 1967 | printf("Looking up: %s\n", host->name); |
| 1968 | #endif |
| 1969 | |
| 1970 | #if HAVE_IPV6 |
| 1971 | if (running_in_test_harness) |
| 1972 | hostdata = host_fake_gethostbyname(host->name, af, &error_num); |
| 1973 | else |
| 1974 | { |
| 1975 | #if HAVE_GETIPNODEBYNAME |
| 1976 | hostdata = getipnodebyname(CS host->name, af, 0, &error_num); |
| 1977 | #else |
| 1978 | hostdata = gethostbyname2(CS host->name, af); |
| 1979 | error_num = h_errno; |
| 1980 | #endif |
| 1981 | } |
| 1982 | |
| 1983 | #else /* not HAVE_IPV6 */ |
| 1984 | if (running_in_test_harness) |
| 1985 | hostdata = host_fake_gethostbyname(host->name, AF_INET, &error_num); |
| 1986 | else |
| 1987 | { |
| 1988 | hostdata = gethostbyname(CS host->name); |
| 1989 | error_num = h_errno; |
| 1990 | } |
| 1991 | #endif /* HAVE_IPV6 */ |
| 1992 | |
| 1993 | if (hostdata == NULL) |
| 1994 | { |
| 1995 | uschar *error; |
| 1996 | switch (error_num) |
| 1997 | { |
| 1998 | case HOST_NOT_FOUND: error = US"HOST_NOT_FOUND"; break; |
| 1999 | case TRY_AGAIN: error = US"TRY_AGAIN"; break; |
| 2000 | case NO_RECOVERY: error = US"NO_RECOVERY"; break; |
| 2001 | case NO_DATA: error = US"NO_DATA"; break; |
| 2002 | #if NO_DATA != NO_ADDRESS |
| 2003 | case NO_ADDRESS: error = US"NO_ADDRESS"; break; |
| 2004 | #endif |
| 2005 | default: error = US"?"; break; |
| 2006 | } |
| 2007 | |
| 2008 | DEBUG(D_host_lookup) debug_printf("%s returned %d (%s)\n", |
| 2009 | #if HAVE_IPV6 |
| 2010 | #if HAVE_GETIPNODEBYNAME |
| 2011 | (af == AF_INET6)? "getipnodebyname(af=inet6)" : "getipnodebyname(af=inet)", |
| 2012 | #else |
| 2013 | (af == AF_INET6)? "gethostbyname2(af=inet6)" : "gethostbyname2(af=inet)", |
| 2014 | #endif |
| 2015 | #else |
| 2016 | "gethostbyname", |
| 2017 | #endif |
| 2018 | error_num, error); |
| 2019 | |
| 2020 | if (error_num == TRY_AGAIN || error_num == NO_RECOVERY) temp_error = TRUE; |
| 2021 | continue; |
| 2022 | } |
| 2023 | if ((hostdata->h_addr_list)[0] == NULL) continue; |
| 2024 | |
| 2025 | /* Replace the name with the fully qualified one if necessary, and fill in |
| 2026 | the fully_qualified_name pointer. */ |
| 2027 | |
| 2028 | if (hostdata->h_name[0] != 0 && |
| 2029 | Ustrcmp(host->name, hostdata->h_name) != 0) |
| 2030 | host->name = string_copy_dnsdomain((uschar *)hostdata->h_name); |
| 2031 | if (fully_qualified_name != NULL) *fully_qualified_name = host->name; |
| 2032 | |
| 2033 | /* Get the list of addresses. IPv4 and IPv6 addresses can be distinguished |
| 2034 | by their different lengths. Scan the list, ignoring any that are to be |
| 2035 | ignored, and build a chain from the rest. */ |
| 2036 | |
| 2037 | ipv4_addr = hostdata->h_length == sizeof(struct in_addr); |
| 2038 | |
| 2039 | for (addrlist = USS hostdata->h_addr_list; *addrlist != NULL; addrlist++) |
| 2040 | { |
| 2041 | uschar *text_address = |
| 2042 | host_ntoa(ipv4_addr? AF_INET:AF_INET6, *addrlist, NULL, NULL); |
| 2043 | |
| 2044 | #ifndef STAND_ALONE |
| 2045 | if (ignore_target_hosts != NULL && |
| 2046 | verify_check_this_host(&ignore_target_hosts, NULL, host->name, |
| 2047 | text_address, NULL) == OK) |
| 2048 | { |
| 2049 | DEBUG(D_host_lookup) |
| 2050 | debug_printf("ignored host %s [%s]\n", host->name, text_address); |
| 2051 | continue; |
| 2052 | } |
| 2053 | #endif |
| 2054 | |
| 2055 | /* If this is the first address, last == NULL and we put the data in the |
| 2056 | original block. */ |
| 2057 | |
| 2058 | if (last == NULL) |
| 2059 | { |
| 2060 | host->address = text_address; |
| 2061 | host->port = PORT_NONE; |
| 2062 | host->status = hstatus_unknown; |
| 2063 | host->why = hwhy_unknown; |
| 2064 | host->dnssec = DS_UNK; |
| 2065 | last = host; |
| 2066 | } |
| 2067 | |
| 2068 | /* Else add further host item blocks for any other addresses, keeping |
| 2069 | the order. */ |
| 2070 | |
| 2071 | else |
| 2072 | { |
| 2073 | host_item *next = store_get(sizeof(host_item)); |
| 2074 | next->name = host->name; |
| 2075 | next->mx = host->mx; |
| 2076 | next->address = text_address; |
| 2077 | next->port = PORT_NONE; |
| 2078 | next->status = hstatus_unknown; |
| 2079 | next->why = hwhy_unknown; |
| 2080 | next->dnssec = DS_UNK; |
| 2081 | next->last_try = 0; |
| 2082 | next->next = last->next; |
| 2083 | last->next = next; |
| 2084 | last = next; |
| 2085 | } |
| 2086 | } |
| 2087 | } |
| 2088 | |
| 2089 | /* If no hosts were found, the address field in the original host block will be |
| 2090 | NULL. If temp_error is set, at least one of the lookups gave a temporary error, |
| 2091 | so we pass that back. */ |
| 2092 | |
| 2093 | if (host->address == NULL) |
| 2094 | { |
| 2095 | uschar *msg = |
| 2096 | #ifndef STAND_ALONE |
| 2097 | (message_id[0] == 0 && smtp_in != NULL)? |
| 2098 | string_sprintf("no IP address found for host %s (during %s)", host->name, |
| 2099 | smtp_get_connection_info()) : |
| 2100 | #endif |
| 2101 | string_sprintf("no IP address found for host %s", host->name); |
| 2102 | |
| 2103 | HDEBUG(D_host_lookup) debug_printf("%s\n", msg); |
| 2104 | if (temp_error) goto RETURN_AGAIN; |
| 2105 | if (host_checking || !log_testing_mode) |
| 2106 | log_write(L_host_lookup_failed, LOG_MAIN, "%s", msg); |
| 2107 | return HOST_FIND_FAILED; |
| 2108 | } |
| 2109 | |
| 2110 | /* Remove any duplicate IP addresses, then check to see if this is the local |
| 2111 | host if required. */ |
| 2112 | |
| 2113 | host_remove_duplicates(host, &last); |
| 2114 | yield = local_host_check? |
| 2115 | host_scan_for_local_hosts(host, &last, NULL) : HOST_FOUND; |
| 2116 | |
| 2117 | HDEBUG(D_host_lookup) |
| 2118 | { |
| 2119 | host_item *h; |
| 2120 | if (fully_qualified_name != NULL) |
| 2121 | debug_printf("fully qualified name = %s\n", *fully_qualified_name); |
| 2122 | debug_printf("%s looked up these IP addresses:\n", |
| 2123 | #if HAVE_IPV6 |
| 2124 | #if HAVE_GETIPNODEBYNAME |
| 2125 | "getipnodebyname" |
| 2126 | #else |
| 2127 | "gethostbyname2" |
| 2128 | #endif |
| 2129 | #else |
| 2130 | "gethostbyname" |
| 2131 | #endif |
| 2132 | ); |
| 2133 | for (h = host; h != last->next; h = h->next) |
| 2134 | debug_printf(" name=%s address=%s\n", h->name, |
| 2135 | (h->address == NULL)? US"<null>" : h->address); |
| 2136 | } |
| 2137 | |
| 2138 | /* Return the found status. */ |
| 2139 | |
| 2140 | return yield; |
| 2141 | |
| 2142 | /* Handle the case when there is a temporary error. If the name matches |
| 2143 | dns_again_means_nonexist, return permanent rather than temporary failure. */ |
| 2144 | |
| 2145 | RETURN_AGAIN: |
| 2146 | { |
| 2147 | #ifndef STAND_ALONE |
| 2148 | int rc; |
| 2149 | uschar *save = deliver_domain; |
| 2150 | deliver_domain = host->name; /* set $domain */ |
| 2151 | rc = match_isinlist(host->name, &dns_again_means_nonexist, 0, NULL, NULL, |
| 2152 | MCL_DOMAIN, TRUE, NULL); |
| 2153 | deliver_domain = save; |
| 2154 | if (rc == OK) |
| 2155 | { |
| 2156 | DEBUG(D_host_lookup) debug_printf("%s is in dns_again_means_nonexist: " |
| 2157 | "returning HOST_FIND_FAILED\n", host->name); |
| 2158 | return HOST_FIND_FAILED; |
| 2159 | } |
| 2160 | #endif |
| 2161 | return HOST_FIND_AGAIN; |
| 2162 | } |
| 2163 | } |
| 2164 | |
| 2165 | |
| 2166 | |
| 2167 | /************************************************* |
| 2168 | * Fill in a host address from the DNS * |
| 2169 | *************************************************/ |
| 2170 | |
| 2171 | /* Given a host item, with its name, port and mx fields set, and its address |
| 2172 | field set to NULL, fill in its IP address from the DNS. If it is multi-homed, |
| 2173 | create additional host items for the additional addresses, copying all the |
| 2174 | other fields, and randomizing the order. |
| 2175 | |
| 2176 | On IPv6 systems, A6 records are sought first (but only if support for A6 is |
| 2177 | configured - they may never become mainstream), then AAAA records are sought, |
| 2178 | and finally A records are sought as well. |
| 2179 | |
| 2180 | The host name may be changed if the DNS returns a different name - e.g. fully |
| 2181 | qualified or changed via CNAME. If fully_qualified_name is not NULL, dns_lookup |
| 2182 | ensures that it points to the fully qualified name. However, this is the fully |
| 2183 | qualified version of the original name; if a CNAME is involved, the actual |
| 2184 | canonical host name may be different again, and so we get it directly from the |
| 2185 | relevant RR. Note that we do NOT change the mx field of the host item in this |
| 2186 | function as it may be called to set the addresses of hosts taken from MX |
| 2187 | records. |
| 2188 | |
| 2189 | Arguments: |
| 2190 | host points to the host item we're filling in |
| 2191 | lastptr points to pointer to last host item in a chain of |
| 2192 | host items (may be updated if host is last and gets |
| 2193 | extended because multihomed) |
| 2194 | ignore_target_hosts list of hosts to ignore |
| 2195 | allow_ip if TRUE, recognize an IP address and return it |
| 2196 | fully_qualified_name if not NULL, return fully qualified name here if |
| 2197 | the contents are different (i.e. it must be preset |
| 2198 | to something) |
| 2199 | dnnssec_require if TRUE check the DNS result AD bit |
| 2200 | |
| 2201 | Returns: HOST_FIND_FAILED couldn't find A record |
| 2202 | HOST_FIND_AGAIN try again later |
| 2203 | HOST_FOUND found AAAA and/or A record(s) |
| 2204 | HOST_IGNORED found, but all IPs ignored |
| 2205 | */ |
| 2206 | |
| 2207 | static int |
| 2208 | set_address_from_dns(host_item *host, host_item **lastptr, |
| 2209 | uschar *ignore_target_hosts, BOOL allow_ip, uschar **fully_qualified_name, |
| 2210 | BOOL dnssec_request, BOOL dnssec_require) |
| 2211 | { |
| 2212 | dns_record *rr; |
| 2213 | host_item *thishostlast = NULL; /* Indicates not yet filled in anything */ |
| 2214 | BOOL v6_find_again = FALSE; |
| 2215 | int i; |
| 2216 | |
| 2217 | /* If allow_ip is set, a name which is an IP address returns that value |
| 2218 | as its address. This is used for MX records when allow_mx_to_ip is set, for |
| 2219 | those sites that feel they have to flaunt the RFC rules. */ |
| 2220 | |
| 2221 | if (allow_ip && string_is_ip_address(host->name, NULL) != 0) |
| 2222 | { |
| 2223 | #ifndef STAND_ALONE |
| 2224 | if (ignore_target_hosts != NULL && |
| 2225 | verify_check_this_host(&ignore_target_hosts, NULL, host->name, |
| 2226 | host->name, NULL) == OK) |
| 2227 | return HOST_IGNORED; |
| 2228 | #endif |
| 2229 | |
| 2230 | host->address = host->name; |
| 2231 | return HOST_FOUND; |
| 2232 | } |
| 2233 | |
| 2234 | /* On an IPv6 system, unless IPv6 is disabled, go round the loop up to three |
| 2235 | times, looking for A6 and AAAA records the first two times. However, unless |
| 2236 | doing standalone testing, we force an IPv4 lookup if the domain matches |
| 2237 | dns_ipv4_lookup is set. Since A6 records look like being abandoned, support |
| 2238 | them only if explicitly configured to do so. On an IPv4 system, go round the |
| 2239 | loop once only, looking only for A records. */ |
| 2240 | |
| 2241 | #if HAVE_IPV6 |
| 2242 | #ifndef STAND_ALONE |
| 2243 | if (disable_ipv6 || (dns_ipv4_lookup != NULL && |
| 2244 | match_isinlist(host->name, &dns_ipv4_lookup, 0, NULL, NULL, MCL_DOMAIN, |
| 2245 | TRUE, NULL) == OK)) |
| 2246 | i = 0; /* look up A records only */ |
| 2247 | else |
| 2248 | #endif /* STAND_ALONE */ |
| 2249 | |
| 2250 | #ifdef SUPPORT_A6 |
| 2251 | i = 2; /* look up A6 and AAAA and A records */ |
| 2252 | #else |
| 2253 | i = 1; /* look up AAAA and A records */ |
| 2254 | #endif /* SUPPORT_A6 */ |
| 2255 | |
| 2256 | /* The IPv4 world */ |
| 2257 | |
| 2258 | #else /* HAVE_IPV6 */ |
| 2259 | i = 0; /* look up A records only */ |
| 2260 | #endif /* HAVE_IPV6 */ |
| 2261 | |
| 2262 | for (; i >= 0; i--) |
| 2263 | { |
| 2264 | static int types[] = { T_A, T_AAAA, T_A6 }; |
| 2265 | int type = types[i]; |
| 2266 | int randoffset = (i == 0)? 500 : 0; /* Ensures v6 sorts before v4 */ |
| 2267 | dns_answer dnsa; |
| 2268 | dns_scan dnss; |
| 2269 | |
| 2270 | int rc = dns_lookup(&dnsa, host->name, type, fully_qualified_name); |
| 2271 | lookup_dnssec_authenticated = !dnssec_request ? NULL |
| 2272 | : dns_is_secure(&dnsa) ? US"yes" : US"no"; |
| 2273 | |
| 2274 | /* We want to return HOST_FIND_AGAIN if one of the A, A6, or AAAA lookups |
| 2275 | fails or times out, but not if another one succeeds. (In the early |
| 2276 | IPv6 days there are name servers that always fail on AAAA, but are happy |
| 2277 | to give out an A record. We want to proceed with that A record.) */ |
| 2278 | |
| 2279 | if (rc != DNS_SUCCEED) |
| 2280 | { |
| 2281 | if (i == 0) /* Just tried for an A record, i.e. end of loop */ |
| 2282 | { |
| 2283 | if (host->address != NULL) return HOST_FOUND; /* A6 or AAAA was found */ |
| 2284 | if (rc == DNS_AGAIN || rc == DNS_FAIL || v6_find_again) |
| 2285 | return HOST_FIND_AGAIN; |
| 2286 | return HOST_FIND_FAILED; /* DNS_NOMATCH or DNS_NODATA */ |
| 2287 | } |
| 2288 | |
| 2289 | /* Tried for an A6 or AAAA record: remember if this was a temporary |
| 2290 | error, and look for the next record type. */ |
| 2291 | |
| 2292 | if (rc != DNS_NOMATCH && rc != DNS_NODATA) v6_find_again = TRUE; |
| 2293 | continue; |
| 2294 | } |
| 2295 | |
| 2296 | if (dnssec_request) |
| 2297 | { |
| 2298 | if (dns_is_secure(&dnsa)) |
| 2299 | { |
| 2300 | DEBUG(D_host_lookup) debug_printf("%s A DNSSEC\n", host->name); |
| 2301 | if (host->dnssec == DS_UNK) /* set in host_find_bydns() */ |
| 2302 | host->dnssec = DS_YES; |
| 2303 | } |
| 2304 | else |
| 2305 | { |
| 2306 | if (dnssec_require) |
| 2307 | { |
| 2308 | log_write(L_host_lookup_failed, LOG_MAIN, |
| 2309 | "dnssec fail on %s for %.256s", |
| 2310 | i>1 ? "A6" : i>0 ? "AAAA" : "A", host->name); |
| 2311 | continue; |
| 2312 | } |
| 2313 | if (host->dnssec == DS_YES) /* set in host_find_bydns() */ |
| 2314 | { |
| 2315 | DEBUG(D_host_lookup) debug_printf("%s A cancel DNSSEC\n", host->name); |
| 2316 | host->dnssec = DS_NO; |
| 2317 | lookup_dnssec_authenticated = US"no"; |
| 2318 | } |
| 2319 | } |
| 2320 | } |
| 2321 | |
| 2322 | /* Lookup succeeded: fill in the given host item with the first non-ignored |
| 2323 | address found; create additional items for any others. A single A6 record |
| 2324 | may generate more than one address. */ |
| 2325 | |
| 2326 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 2327 | rr != NULL; |
| 2328 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 2329 | { |
| 2330 | if (rr->type == type) |
| 2331 | { |
| 2332 | /* dns_address *da = dns_address_from_rr(&dnsa, rr); */ |
| 2333 | |
| 2334 | dns_address *da; |
| 2335 | da = dns_address_from_rr(&dnsa, rr); |
| 2336 | |
| 2337 | DEBUG(D_host_lookup) |
| 2338 | { |
| 2339 | if (da == NULL) |
| 2340 | debug_printf("no addresses extracted from A6 RR for %s\n", |
| 2341 | host->name); |
| 2342 | } |
| 2343 | |
| 2344 | /* This loop runs only once for A and AAAA records, but may run |
| 2345 | several times for an A6 record that generated multiple addresses. */ |
| 2346 | |
| 2347 | for (; da != NULL; da = da->next) |
| 2348 | { |
| 2349 | #ifndef STAND_ALONE |
| 2350 | if (ignore_target_hosts != NULL && |
| 2351 | verify_check_this_host(&ignore_target_hosts, NULL, |
| 2352 | host->name, da->address, NULL) == OK) |
| 2353 | { |
| 2354 | DEBUG(D_host_lookup) |
| 2355 | debug_printf("ignored host %s [%s]\n", host->name, da->address); |
| 2356 | continue; |
| 2357 | } |
| 2358 | #endif |
| 2359 | |
| 2360 | /* If this is the first address, stick it in the given host block, |
| 2361 | and change the name if the returned RR has a different name. */ |
| 2362 | |
| 2363 | if (thishostlast == NULL) |
| 2364 | { |
| 2365 | if (strcmpic(host->name, rr->name) != 0) |
| 2366 | host->name = string_copy_dnsdomain(rr->name); |
| 2367 | host->address = da->address; |
| 2368 | host->sort_key = host->mx * 1000 + random_number(500) + randoffset; |
| 2369 | host->status = hstatus_unknown; |
| 2370 | host->why = hwhy_unknown; |
| 2371 | thishostlast = host; |
| 2372 | } |
| 2373 | |
| 2374 | /* Not the first address. Check for, and ignore, duplicates. Then |
| 2375 | insert in the chain at a random point. */ |
| 2376 | |
| 2377 | else |
| 2378 | { |
| 2379 | int new_sort_key; |
| 2380 | host_item *next; |
| 2381 | |
| 2382 | /* End of our local chain is specified by "thishostlast". */ |
| 2383 | |
| 2384 | for (next = host;; next = next->next) |
| 2385 | { |
| 2386 | if (Ustrcmp(CS da->address, next->address) == 0) break; |
| 2387 | if (next == thishostlast) { next = NULL; break; } |
| 2388 | } |
| 2389 | if (next != NULL) continue; /* With loop for next address */ |
| 2390 | |
| 2391 | /* Not a duplicate */ |
| 2392 | |
| 2393 | new_sort_key = host->mx * 1000 + random_number(500) + randoffset; |
| 2394 | next = store_get(sizeof(host_item)); |
| 2395 | |
| 2396 | /* New address goes first: insert the new block after the first one |
| 2397 | (so as not to disturb the original pointer) but put the new address |
| 2398 | in the original block. */ |
| 2399 | |
| 2400 | if (new_sort_key < host->sort_key) |
| 2401 | { |
| 2402 | *next = *host; /* Copies port */ |
| 2403 | host->next = next; |
| 2404 | host->address = da->address; |
| 2405 | host->sort_key = new_sort_key; |
| 2406 | if (thishostlast == host) thishostlast = next; /* Local last */ |
| 2407 | if (*lastptr == host) *lastptr = next; /* Global last */ |
| 2408 | } |
| 2409 | |
| 2410 | /* Otherwise scan down the addresses for this host to find the |
| 2411 | one to insert after. */ |
| 2412 | |
| 2413 | else |
| 2414 | { |
| 2415 | host_item *h = host; |
| 2416 | while (h != thishostlast) |
| 2417 | { |
| 2418 | if (new_sort_key < h->next->sort_key) break; |
| 2419 | h = h->next; |
| 2420 | } |
| 2421 | *next = *h; /* Copies port */ |
| 2422 | h->next = next; |
| 2423 | next->address = da->address; |
| 2424 | next->sort_key = new_sort_key; |
| 2425 | if (h == thishostlast) thishostlast = next; /* Local last */ |
| 2426 | if (h == *lastptr) *lastptr = next; /* Global last */ |
| 2427 | } |
| 2428 | } |
| 2429 | } |
| 2430 | } |
| 2431 | } |
| 2432 | } |
| 2433 | |
| 2434 | /* Control gets here only if the third lookup (the A record) succeeded. |
| 2435 | However, the address may not be filled in if it was ignored. */ |
| 2436 | |
| 2437 | return (host->address == NULL)? HOST_IGNORED : HOST_FOUND; |
| 2438 | } |
| 2439 | |
| 2440 | |
| 2441 | |
| 2442 | |
| 2443 | /************************************************* |
| 2444 | * Find IP addresses and host names via DNS * |
| 2445 | *************************************************/ |
| 2446 | |
| 2447 | /* The input is a host_item structure with the name field filled in and the |
| 2448 | address field set to NULL. This may be in a chain of other host items. The |
| 2449 | lookup may result in more than one IP address, in which case we must created |
| 2450 | new host blocks for the additional addresses, and insert them into the chain. |
| 2451 | The original name may not be fully qualified. Use the fully_qualified_name |
| 2452 | argument to return the official name, as returned by the resolver. |
| 2453 | |
| 2454 | Arguments: |
| 2455 | host point to initial host item |
| 2456 | ignore_target_hosts a list of hosts to ignore |
| 2457 | whichrrs flags indicating which RRs to look for: |
| 2458 | HOST_FIND_BY_SRV => look for SRV |
| 2459 | HOST_FIND_BY_MX => look for MX |
| 2460 | HOST_FIND_BY_A => look for A or AAAA |
| 2461 | also flags indicating how the lookup is done |
| 2462 | HOST_FIND_QUALIFY_SINGLE ) passed to the |
| 2463 | HOST_FIND_SEARCH_PARENTS ) resolver |
| 2464 | srv_service when SRV used, the service name |
| 2465 | srv_fail_domains DNS errors for these domains => assume nonexist |
| 2466 | mx_fail_domains DNS errors for these domains => assume nonexist |
| 2467 | dnssec_request_domains => make dnssec request |
| 2468 | dnssec_require_domains => ditto and nonexist failures |
| 2469 | fully_qualified_name if not NULL, return fully-qualified name |
| 2470 | removed set TRUE if local host was removed from the list |
| 2471 | |
| 2472 | Returns: HOST_FIND_FAILED Failed to find the host or domain; |
| 2473 | if there was a syntax error, |
| 2474 | host_find_failed_syntax is set. |
| 2475 | HOST_FIND_AGAIN Could not resolve at this time |
| 2476 | HOST_FOUND Host found |
| 2477 | HOST_FOUND_LOCAL The lowest MX record points to this |
| 2478 | machine, if MX records were found, or |
| 2479 | an A record that was found contains |
| 2480 | an address of the local host |
| 2481 | */ |
| 2482 | |
| 2483 | int |
| 2484 | host_find_bydns(host_item *host, uschar *ignore_target_hosts, int whichrrs, |
| 2485 | uschar *srv_service, uschar *srv_fail_domains, uschar *mx_fail_domains, |
| 2486 | uschar *dnssec_request_domains, uschar *dnssec_require_domains, |
| 2487 | uschar **fully_qualified_name, BOOL *removed) |
| 2488 | { |
| 2489 | host_item *h, *last; |
| 2490 | dns_record *rr; |
| 2491 | int rc = DNS_FAIL; |
| 2492 | int ind_type = 0; |
| 2493 | int yield; |
| 2494 | dns_answer dnsa; |
| 2495 | dns_scan dnss; |
| 2496 | BOOL dnssec_require = match_isinlist(host->name, &dnssec_require_domains, |
| 2497 | 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK; |
| 2498 | BOOL dnssec_request = dnssec_require |
| 2499 | || match_isinlist(host->name, &dnssec_request_domains, |
| 2500 | 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK; |
| 2501 | dnssec_status_t dnssec; |
| 2502 | |
| 2503 | /* Set the default fully qualified name to the incoming name, initialize the |
| 2504 | resolver if necessary, set up the relevant options, and initialize the flag |
| 2505 | that gets set for DNS syntax check errors. */ |
| 2506 | |
| 2507 | if (fully_qualified_name != NULL) *fully_qualified_name = host->name; |
| 2508 | dns_init((whichrrs & HOST_FIND_QUALIFY_SINGLE) != 0, |
| 2509 | (whichrrs & HOST_FIND_SEARCH_PARENTS) != 0, |
| 2510 | dnssec_request |
| 2511 | ); |
| 2512 | host_find_failed_syntax = FALSE; |
| 2513 | |
| 2514 | /* First, if requested, look for SRV records. The service name is given; we |
| 2515 | assume TCP progocol. DNS domain names are constrained to a maximum of 256 |
| 2516 | characters, so the code below should be safe. */ |
| 2517 | |
| 2518 | if ((whichrrs & HOST_FIND_BY_SRV) != 0) |
| 2519 | { |
| 2520 | uschar buffer[300]; |
| 2521 | uschar *temp_fully_qualified_name = buffer; |
| 2522 | int prefix_length; |
| 2523 | |
| 2524 | (void)sprintf(CS buffer, "_%s._tcp.%n%.256s", srv_service, &prefix_length, |
| 2525 | host->name); |
| 2526 | ind_type = T_SRV; |
| 2527 | |
| 2528 | /* Search for SRV records. If the fully qualified name is different to |
| 2529 | the input name, pass back the new original domain, without the prepended |
| 2530 | magic. */ |
| 2531 | |
| 2532 | dnssec = DS_UNK; |
| 2533 | lookup_dnssec_authenticated = NULL; |
| 2534 | rc = dns_lookup(&dnsa, buffer, ind_type, &temp_fully_qualified_name); |
| 2535 | |
| 2536 | if (dnssec_request) |
| 2537 | { |
| 2538 | if (dns_is_secure(&dnsa)) |
| 2539 | { dnssec = DS_YES; lookup_dnssec_authenticated = US"yes"; } |
| 2540 | else |
| 2541 | { dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; } |
| 2542 | } |
| 2543 | |
| 2544 | if (temp_fully_qualified_name != buffer && fully_qualified_name != NULL) |
| 2545 | *fully_qualified_name = temp_fully_qualified_name + prefix_length; |
| 2546 | |
| 2547 | /* On DNS failures, we give the "try again" error unless the domain is |
| 2548 | listed as one for which we continue. */ |
| 2549 | |
| 2550 | if (rc == DNS_SUCCEED && dnssec_require && !dns_is_secure(&dnsa)) |
| 2551 | { |
| 2552 | log_write(L_host_lookup_failed, LOG_MAIN, |
| 2553 | "dnssec fail on SRV for %.256s", host->name); |
| 2554 | rc = DNS_FAIL; |
| 2555 | } |
| 2556 | if (rc == DNS_FAIL || rc == DNS_AGAIN) |
| 2557 | { |
| 2558 | #ifndef STAND_ALONE |
| 2559 | if (match_isinlist(host->name, &srv_fail_domains, 0, NULL, NULL, MCL_DOMAIN, |
| 2560 | TRUE, NULL) != OK) |
| 2561 | #endif |
| 2562 | { yield = HOST_FIND_AGAIN; goto out; } |
| 2563 | DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA " |
| 2564 | "(domain in srv_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN"); |
| 2565 | } |
| 2566 | } |
| 2567 | |
| 2568 | /* If we did not find any SRV records, search the DNS for MX records, if |
| 2569 | requested to do so. If the result is DNS_NOMATCH, it means there is no such |
| 2570 | domain, and there's no point in going on to look for address records with the |
| 2571 | same domain. The result will be DNS_NODATA if the domain exists but has no MX |
| 2572 | records. On DNS failures, we give the "try again" error unless the domain is |
| 2573 | listed as one for which we continue. */ |
| 2574 | |
| 2575 | if (rc != DNS_SUCCEED && (whichrrs & HOST_FIND_BY_MX) != 0) |
| 2576 | { |
| 2577 | ind_type = T_MX; |
| 2578 | dnssec = DS_UNK; |
| 2579 | lookup_dnssec_authenticated = NULL; |
| 2580 | rc = dns_lookup(&dnsa, host->name, ind_type, fully_qualified_name); |
| 2581 | |
| 2582 | if (dnssec_request) |
| 2583 | { |
| 2584 | if (dns_is_secure(&dnsa)) |
| 2585 | { |
| 2586 | DEBUG(D_host_lookup) debug_printf("%s MX DNSSEC\n", host->name); |
| 2587 | dnssec = DS_YES; lookup_dnssec_authenticated = US"yes"; |
| 2588 | } |
| 2589 | else |
| 2590 | { |
| 2591 | dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; |
| 2592 | } |
| 2593 | } |
| 2594 | |
| 2595 | switch (rc) |
| 2596 | { |
| 2597 | case DNS_NOMATCH: |
| 2598 | yield = HOST_FIND_FAILED; goto out; |
| 2599 | |
| 2600 | case DNS_SUCCEED: |
| 2601 | if (!dnssec_require || dns_is_secure(&dnsa)) |
| 2602 | break; |
| 2603 | log_write(L_host_lookup_failed, LOG_MAIN, |
| 2604 | "dnssec fail on MX for %.256s", host->name); |
| 2605 | rc = DNS_FAIL; |
| 2606 | /*FALLTHROUGH*/ |
| 2607 | |
| 2608 | case DNS_FAIL: |
| 2609 | case DNS_AGAIN: |
| 2610 | #ifndef STAND_ALONE |
| 2611 | if (match_isinlist(host->name, &mx_fail_domains, 0, NULL, NULL, MCL_DOMAIN, |
| 2612 | TRUE, NULL) != OK) |
| 2613 | #endif |
| 2614 | { yield = HOST_FIND_AGAIN; goto out; } |
| 2615 | DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA " |
| 2616 | "(domain in mx_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN"); |
| 2617 | break; |
| 2618 | } |
| 2619 | } |
| 2620 | |
| 2621 | /* If we haven't found anything yet, and we are requested to do so, try for an |
| 2622 | A or AAAA record. If we find it (or them) check to see that it isn't the local |
| 2623 | host. */ |
| 2624 | |
| 2625 | if (rc != DNS_SUCCEED) |
| 2626 | { |
| 2627 | if ((whichrrs & HOST_FIND_BY_A) == 0) |
| 2628 | { |
| 2629 | DEBUG(D_host_lookup) debug_printf("Address records are not being sought\n"); |
| 2630 | yield = HOST_FIND_FAILED; |
| 2631 | goto out; |
| 2632 | } |
| 2633 | |
| 2634 | last = host; /* End of local chainlet */ |
| 2635 | host->mx = MX_NONE; |
| 2636 | host->port = PORT_NONE; |
| 2637 | host->dnssec = DS_UNK; |
| 2638 | lookup_dnssec_authenticated = NULL; |
| 2639 | rc = set_address_from_dns(host, &last, ignore_target_hosts, FALSE, |
| 2640 | fully_qualified_name, dnssec_request, dnssec_require); |
| 2641 | |
| 2642 | /* If one or more address records have been found, check that none of them |
| 2643 | are local. Since we know the host items all have their IP addresses |
| 2644 | inserted, host_scan_for_local_hosts() can only return HOST_FOUND or |
| 2645 | HOST_FOUND_LOCAL. We do not need to scan for duplicate IP addresses here, |
| 2646 | because set_address_from_dns() removes them. */ |
| 2647 | |
| 2648 | if (rc == HOST_FOUND) |
| 2649 | rc = host_scan_for_local_hosts(host, &last, removed); |
| 2650 | else |
| 2651 | if (rc == HOST_IGNORED) rc = HOST_FIND_FAILED; /* No special action */ |
| 2652 | |
| 2653 | DEBUG(D_host_lookup) |
| 2654 | { |
| 2655 | host_item *h; |
| 2656 | if (host->address != NULL) |
| 2657 | { |
| 2658 | if (fully_qualified_name != NULL) |
| 2659 | debug_printf("fully qualified name = %s\n", *fully_qualified_name); |
| 2660 | for (h = host; h != last->next; h = h->next) |
| 2661 | debug_printf("%s %s mx=%d sort=%d %s\n", h->name, |
| 2662 | (h->address == NULL)? US"<null>" : h->address, h->mx, h->sort_key, |
| 2663 | (h->status >= hstatus_unusable)? US"*" : US""); |
| 2664 | } |
| 2665 | } |
| 2666 | |
| 2667 | yield = rc; |
| 2668 | goto out; |
| 2669 | } |
| 2670 | |
| 2671 | /* We have found one or more MX or SRV records. Sort them according to |
| 2672 | precedence. Put the data for the first one into the existing host block, and |
| 2673 | insert new host_item blocks into the chain for the remainder. For equal |
| 2674 | precedences one is supposed to randomize the order. To make this happen, the |
| 2675 | sorting is actually done on the MX value * 1000 + a random number. This is put |
| 2676 | into a host field called sort_key. |
| 2677 | |
| 2678 | In the case of hosts with both IPv6 and IPv4 addresses, we want to choose the |
| 2679 | IPv6 address in preference. At this stage, we don't know what kind of address |
| 2680 | the host has. We choose a random number < 500; if later we find an A record |
| 2681 | first, we add 500 to the random number. Then for any other address records, we |
| 2682 | use random numbers in the range 0-499 for AAAA records and 500-999 for A |
| 2683 | records. |
| 2684 | |
| 2685 | At this point we remove any duplicates that point to the same host, retaining |
| 2686 | only the one with the lowest precedence. We cannot yet check for precedence |
| 2687 | greater than that of the local host, because that test cannot be properly done |
| 2688 | until the addresses have been found - an MX record may point to a name for this |
| 2689 | host which is not the primary hostname. */ |
| 2690 | |
| 2691 | last = NULL; /* Indicates that not even the first item is filled yet */ |
| 2692 | |
| 2693 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 2694 | rr != NULL; |
| 2695 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 2696 | { |
| 2697 | int precedence; |
| 2698 | int weight = 0; /* For SRV records */ |
| 2699 | int port = PORT_NONE; |
| 2700 | uschar *s; /* MUST be unsigned for GETSHORT */ |
| 2701 | uschar data[256]; |
| 2702 | |
| 2703 | if (rr->type != ind_type) continue; |
| 2704 | s = rr->data; |
| 2705 | GETSHORT(precedence, s); /* Pointer s is advanced */ |
| 2706 | |
| 2707 | /* For MX records, we use a random "weight" which causes multiple records of |
| 2708 | the same precedence to sort randomly. */ |
| 2709 | |
| 2710 | if (ind_type == T_MX) |
| 2711 | weight = random_number(500); |
| 2712 | |
| 2713 | /* SRV records are specified with a port and a weight. The weight is used |
| 2714 | in a special algorithm. However, to start with, we just use it to order the |
| 2715 | records of equal priority (precedence). */ |
| 2716 | |
| 2717 | else |
| 2718 | { |
| 2719 | GETSHORT(weight, s); |
| 2720 | GETSHORT(port, s); |
| 2721 | } |
| 2722 | |
| 2723 | /* Get the name of the host pointed to. */ |
| 2724 | |
| 2725 | (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, s, |
| 2726 | (DN_EXPAND_ARG4_TYPE)data, sizeof(data)); |
| 2727 | |
| 2728 | /* Check that we haven't already got this host on the chain; if we have, |
| 2729 | keep only the lower precedence. This situation shouldn't occur, but you |
| 2730 | never know what junk might get into the DNS (and this case has been seen on |
| 2731 | more than one occasion). */ |
| 2732 | |
| 2733 | if (last != NULL) /* This is not the first record */ |
| 2734 | { |
| 2735 | host_item *prev = NULL; |
| 2736 | |
| 2737 | for (h = host; h != last->next; prev = h, h = h->next) |
| 2738 | { |
| 2739 | if (strcmpic(h->name, data) == 0) |
| 2740 | { |
| 2741 | DEBUG(D_host_lookup) |
| 2742 | debug_printf("discarded duplicate host %s (MX=%d)\n", data, |
| 2743 | (precedence > h->mx)? precedence : h->mx); |
| 2744 | if (precedence >= h->mx) goto NEXT_MX_RR; /* Skip greater precedence */ |
| 2745 | if (h == host) /* Override first item */ |
| 2746 | { |
| 2747 | h->mx = precedence; |
| 2748 | host->sort_key = precedence * 1000 + weight; |
| 2749 | goto NEXT_MX_RR; |
| 2750 | } |
| 2751 | |
| 2752 | /* Unwanted host item is not the first in the chain, so we can get |
| 2753 | get rid of it by cutting it out. */ |
| 2754 | |
| 2755 | prev->next = h->next; |
| 2756 | if (h == last) last = prev; |
| 2757 | break; |
| 2758 | } |
| 2759 | } |
| 2760 | } |
| 2761 | |
| 2762 | /* If this is the first MX or SRV record, put the data into the existing host |
| 2763 | block. Otherwise, add a new block in the correct place; if it has to be |
| 2764 | before the first block, copy the first block's data to a new second block. */ |
| 2765 | |
| 2766 | if (last == NULL) |
| 2767 | { |
| 2768 | host->name = string_copy_dnsdomain(data); |
| 2769 | host->address = NULL; |
| 2770 | host->port = port; |
| 2771 | host->mx = precedence; |
| 2772 | host->sort_key = precedence * 1000 + weight; |
| 2773 | host->status = hstatus_unknown; |
| 2774 | host->why = hwhy_unknown; |
| 2775 | host->dnssec = dnssec; |
| 2776 | last = host; |
| 2777 | } |
| 2778 | |
| 2779 | /* Make a new host item and seek the correct insertion place */ |
| 2780 | |
| 2781 | else |
| 2782 | { |
| 2783 | int sort_key = precedence * 1000 + weight; |
| 2784 | host_item *next = store_get(sizeof(host_item)); |
| 2785 | next->name = string_copy_dnsdomain(data); |
| 2786 | next->address = NULL; |
| 2787 | next->port = port; |
| 2788 | next->mx = precedence; |
| 2789 | next->sort_key = sort_key; |
| 2790 | next->status = hstatus_unknown; |
| 2791 | next->why = hwhy_unknown; |
| 2792 | next->dnssec = dnssec; |
| 2793 | next->last_try = 0; |
| 2794 | |
| 2795 | /* Handle the case when we have to insert before the first item. */ |
| 2796 | |
| 2797 | if (sort_key < host->sort_key) |
| 2798 | { |
| 2799 | host_item htemp; |
| 2800 | htemp = *host; |
| 2801 | *host = *next; |
| 2802 | *next = htemp; |
| 2803 | host->next = next; |
| 2804 | if (last == host) last = next; |
| 2805 | } |
| 2806 | |
| 2807 | /* Else scan down the items we have inserted as part of this exercise; |
| 2808 | don't go further. */ |
| 2809 | |
| 2810 | else |
| 2811 | { |
| 2812 | for (h = host; h != last; h = h->next) |
| 2813 | { |
| 2814 | if (sort_key < h->next->sort_key) |
| 2815 | { |
| 2816 | next->next = h->next; |
| 2817 | h->next = next; |
| 2818 | break; |
| 2819 | } |
| 2820 | } |
| 2821 | |
| 2822 | /* Join on after the last host item that's part of this |
| 2823 | processing if we haven't stopped sooner. */ |
| 2824 | |
| 2825 | if (h == last) |
| 2826 | { |
| 2827 | next->next = last->next; |
| 2828 | last->next = next; |
| 2829 | last = next; |
| 2830 | } |
| 2831 | } |
| 2832 | } |
| 2833 | |
| 2834 | NEXT_MX_RR: continue; |
| 2835 | } |
| 2836 | |
| 2837 | /* If the list of hosts was obtained from SRV records, there are two things to |
| 2838 | do. First, if there is only one host, and it's name is ".", it means there is |
| 2839 | no SMTP service at this domain. Otherwise, we have to sort the hosts of equal |
| 2840 | priority according to their weights, using an algorithm that is defined in RFC |
| 2841 | 2782. The hosts are currently sorted by priority and weight. For each priority |
| 2842 | group we have to pick off one host and put it first, and then repeat for any |
| 2843 | remaining in the same priority group. */ |
| 2844 | |
| 2845 | if (ind_type == T_SRV) |
| 2846 | { |
| 2847 | host_item **pptr; |
| 2848 | |
| 2849 | if (host == last && host->name[0] == 0) |
| 2850 | { |
| 2851 | DEBUG(D_host_lookup) debug_printf("the single SRV record is \".\"\n"); |
| 2852 | yield = HOST_FIND_FAILED; |
| 2853 | goto out; |
| 2854 | } |
| 2855 | |
| 2856 | DEBUG(D_host_lookup) |
| 2857 | { |
| 2858 | debug_printf("original ordering of hosts from SRV records:\n"); |
| 2859 | for (h = host; h != last->next; h = h->next) |
| 2860 | debug_printf(" %s P=%d W=%d\n", h->name, h->mx, h->sort_key % 1000); |
| 2861 | } |
| 2862 | |
| 2863 | for (pptr = &host, h = host; h != last; pptr = &(h->next), h = h->next) |
| 2864 | { |
| 2865 | int sum = 0; |
| 2866 | host_item *hh; |
| 2867 | |
| 2868 | /* Find the last following host that has the same precedence. At the same |
| 2869 | time, compute the sum of the weights and the running totals. These can be |
| 2870 | stored in the sort_key field. */ |
| 2871 | |
| 2872 | for (hh = h; hh != last; hh = hh->next) |
| 2873 | { |
| 2874 | int weight = hh->sort_key % 1000; /* was precedence * 1000 + weight */ |
| 2875 | sum += weight; |
| 2876 | hh->sort_key = sum; |
| 2877 | if (hh->mx != hh->next->mx) break; |
| 2878 | } |
| 2879 | |
| 2880 | /* If there's more than one host at this precedence (priority), we need to |
| 2881 | pick one to go first. */ |
| 2882 | |
| 2883 | if (hh != h) |
| 2884 | { |
| 2885 | host_item *hhh; |
| 2886 | host_item **ppptr; |
| 2887 | int randomizer = random_number(sum + 1); |
| 2888 | |
| 2889 | for (ppptr = pptr, hhh = h; |
| 2890 | hhh != hh; |
| 2891 | ppptr = &(hhh->next), hhh = hhh->next) |
| 2892 | { |
| 2893 | if (hhh->sort_key >= randomizer) break; |
| 2894 | } |
| 2895 | |
| 2896 | /* hhh now points to the host that should go first; ppptr points to the |
| 2897 | place that points to it. Unfortunately, if the start of the minilist is |
| 2898 | the start of the entire list, we can't just swap the items over, because |
| 2899 | we must not change the value of host, since it is passed in from outside. |
| 2900 | One day, this could perhaps be changed. |
| 2901 | |
| 2902 | The special case is fudged by putting the new item *second* in the chain, |
| 2903 | and then transferring the data between the first and second items. We |
| 2904 | can't just swap the first and the chosen item, because that would mean |
| 2905 | that an item with zero weight might no longer be first. */ |
| 2906 | |
| 2907 | if (hhh != h) |
| 2908 | { |
| 2909 | *ppptr = hhh->next; /* Cuts it out of the chain */ |
| 2910 | |
| 2911 | if (h == host) |
| 2912 | { |
| 2913 | host_item temp = *h; |
| 2914 | *h = *hhh; |
| 2915 | *hhh = temp; |
| 2916 | hhh->next = temp.next; |
| 2917 | h->next = hhh; |
| 2918 | } |
| 2919 | |
| 2920 | else |
| 2921 | { |
| 2922 | hhh->next = h; /* The rest of the chain follows it */ |
| 2923 | *pptr = hhh; /* It takes the place of h */ |
| 2924 | h = hhh; /* It's now the start of this minilist */ |
| 2925 | } |
| 2926 | } |
| 2927 | } |
| 2928 | |
| 2929 | /* A host has been chosen to be first at this priority and h now points |
| 2930 | to this host. There may be others at the same priority, or others at a |
| 2931 | different priority. Before we leave this host, we need to put back a sort |
| 2932 | key of the traditional MX kind, in case this host is multihomed, because |
| 2933 | the sort key is used for ordering the multiple IP addresses. We do not need |
| 2934 | to ensure that these new sort keys actually reflect the order of the hosts, |
| 2935 | however. */ |
| 2936 | |
| 2937 | h->sort_key = h->mx * 1000 + random_number(500); |
| 2938 | } /* Move on to the next host */ |
| 2939 | } |
| 2940 | |
| 2941 | /* Now we have to find IP addresses for all the hosts. We have ensured above |
| 2942 | that the names in all the host items are unique. Before release 4.61 we used to |
| 2943 | process records from the additional section in the DNS packet that returned the |
| 2944 | MX or SRV records. However, a DNS name server is free to drop any resource |
| 2945 | records from the additional section. In theory, this has always been a |
| 2946 | potential problem, but it is exacerbated by the advent of IPv6. If a host had |
| 2947 | several IPv4 addresses and some were not in the additional section, at least |
| 2948 | Exim would try the others. However, if a host had both IPv4 and IPv6 addresses |
| 2949 | and all the IPv4 (say) addresses were absent, Exim would try only for a IPv6 |
| 2950 | connection, and never try an IPv4 address. When there was only IPv4 |
| 2951 | connectivity, this was a disaster that did in practice occur. |
| 2952 | |
| 2953 | So, from release 4.61 onwards, we always search for A and AAAA records |
| 2954 | explicitly. The names shouldn't point to CNAMES, but we use the general lookup |
| 2955 | function that handles them, just in case. If any lookup gives a soft error, |
| 2956 | change the default yield. |
| 2957 | |
| 2958 | For these DNS lookups, we must disable qualify_single and search_parents; |
| 2959 | otherwise invalid host names obtained from MX or SRV records can cause trouble |
| 2960 | if they happen to match something local. */ |
| 2961 | |
| 2962 | yield = HOST_FIND_FAILED; /* Default yield */ |
| 2963 | dns_init(FALSE, FALSE, /* Disable qualify_single and search_parents */ |
| 2964 | dnssec_request || dnssec_require); |
| 2965 | |
| 2966 | for (h = host; h != last->next; h = h->next) |
| 2967 | { |
| 2968 | if (h->address != NULL) continue; /* Inserted by a multihomed host */ |
| 2969 | rc = set_address_from_dns(h, &last, ignore_target_hosts, allow_mx_to_ip, |
| 2970 | NULL, dnssec_request, dnssec_require); |
| 2971 | if (rc != HOST_FOUND) |
| 2972 | { |
| 2973 | h->status = hstatus_unusable; |
| 2974 | if (rc == HOST_FIND_AGAIN) |
| 2975 | { |
| 2976 | yield = rc; |
| 2977 | h->why = hwhy_deferred; |
| 2978 | } |
| 2979 | else |
| 2980 | h->why = (rc == HOST_IGNORED)? hwhy_ignored : hwhy_failed; |
| 2981 | } |
| 2982 | } |
| 2983 | |
| 2984 | /* Scan the list for any hosts that are marked unusable because they have |
| 2985 | been explicitly ignored, and remove them from the list, as if they did not |
| 2986 | exist. If we end up with just a single, ignored host, flatten its fields as if |
| 2987 | nothing was found. */ |
| 2988 | |
| 2989 | if (ignore_target_hosts != NULL) |
| 2990 | { |
| 2991 | host_item *prev = NULL; |
| 2992 | for (h = host; h != last->next; h = h->next) |
| 2993 | { |
| 2994 | REDO: |
| 2995 | if (h->why != hwhy_ignored) /* Non ignored host, just continue */ |
| 2996 | prev = h; |
| 2997 | else if (prev == NULL) /* First host is ignored */ |
| 2998 | { |
| 2999 | if (h != last) /* First is not last */ |
| 3000 | { |
| 3001 | if (h->next == last) last = h; /* Overwrite it with next */ |
| 3002 | *h = *(h->next); /* and reprocess it. */ |
| 3003 | goto REDO; /* C should have redo, like Perl */ |
| 3004 | } |
| 3005 | } |
| 3006 | else /* Ignored host is not first - */ |
| 3007 | { /* cut it out */ |
| 3008 | prev->next = h->next; |
| 3009 | if (h == last) last = prev; |
| 3010 | } |
| 3011 | } |
| 3012 | |
| 3013 | if (host->why == hwhy_ignored) host->address = NULL; |
| 3014 | } |
| 3015 | |
| 3016 | /* There is still one complication in the case of IPv6. Although the code above |
| 3017 | arranges that IPv6 addresses take precedence over IPv4 addresses for multihomed |
| 3018 | hosts, it doesn't do this for addresses that apply to different hosts with the |
| 3019 | same MX precedence, because the sorting on MX precedence happens first. So we |
| 3020 | have to make another pass to check for this case. We ensure that, within a |
| 3021 | single MX preference value, IPv6 addresses come first. This can separate the |
| 3022 | addresses of a multihomed host, but that should not matter. */ |
| 3023 | |
| 3024 | #if HAVE_IPV6 |
| 3025 | if (h != last && !disable_ipv6) |
| 3026 | { |
| 3027 | for (h = host; h != last; h = h->next) |
| 3028 | { |
| 3029 | host_item temp; |
| 3030 | host_item *next = h->next; |
| 3031 | if (h->mx != next->mx || /* If next is different MX */ |
| 3032 | h->address == NULL || /* OR this one is unset */ |
| 3033 | Ustrchr(h->address, ':') != NULL || /* OR this one is IPv6 */ |
| 3034 | (next->address != NULL && |
| 3035 | Ustrchr(next->address, ':') == NULL)) /* OR next is IPv4 */ |
| 3036 | continue; /* move on to next */ |
| 3037 | temp = *h; /* otherwise, swap */ |
| 3038 | temp.next = next->next; |
| 3039 | *h = *next; |
| 3040 | h->next = next; |
| 3041 | *next = temp; |
| 3042 | } |
| 3043 | } |
| 3044 | #endif |
| 3045 | |
| 3046 | /* Remove any duplicate IP addresses and then scan the list of hosts for any |
| 3047 | whose IP addresses are on the local host. If any are found, all hosts with the |
| 3048 | same or higher MX values are removed. However, if the local host has the lowest |
| 3049 | numbered MX, then HOST_FOUND_LOCAL is returned. Otherwise, if at least one host |
| 3050 | with an IP address is on the list, HOST_FOUND is returned. Otherwise, |
| 3051 | HOST_FIND_FAILED is returned, but in this case do not update the yield, as it |
| 3052 | might have been set to HOST_FIND_AGAIN just above here. If not, it will already |
| 3053 | be HOST_FIND_FAILED. */ |
| 3054 | |
| 3055 | host_remove_duplicates(host, &last); |
| 3056 | rc = host_scan_for_local_hosts(host, &last, removed); |
| 3057 | if (rc != HOST_FIND_FAILED) yield = rc; |
| 3058 | |
| 3059 | DEBUG(D_host_lookup) |
| 3060 | { |
| 3061 | if (fully_qualified_name != NULL) |
| 3062 | debug_printf("fully qualified name = %s\n", *fully_qualified_name); |
| 3063 | debug_printf("host_find_bydns yield = %s (%d); returned hosts:\n", |
| 3064 | (yield == HOST_FOUND)? "HOST_FOUND" : |
| 3065 | (yield == HOST_FOUND_LOCAL)? "HOST_FOUND_LOCAL" : |
| 3066 | (yield == HOST_FIND_AGAIN)? "HOST_FIND_AGAIN" : |
| 3067 | (yield == HOST_FIND_FAILED)? "HOST_FIND_FAILED" : "?", |
| 3068 | yield); |
| 3069 | for (h = host; h != last->next; h = h->next) |
| 3070 | { |
| 3071 | debug_printf(" %s %s MX=%d ", h->name, |
| 3072 | (h->address == NULL)? US"<null>" : h->address, h->mx); |
| 3073 | if (h->port != PORT_NONE) debug_printf("port=%d ", h->port); |
| 3074 | if (h->status >= hstatus_unusable) debug_printf("*"); |
| 3075 | debug_printf("\n"); |
| 3076 | } |
| 3077 | } |
| 3078 | |
| 3079 | out: |
| 3080 | |
| 3081 | dns_init(FALSE, FALSE, FALSE); /* clear the dnssec bit for getaddrbyname */ |
| 3082 | return yield; |
| 3083 | } |
| 3084 | |
| 3085 | |
| 3086 | |
| 3087 | |
| 3088 | /************************************************* |
| 3089 | ************************************************** |
| 3090 | * Stand-alone test program * |
| 3091 | ************************************************** |
| 3092 | *************************************************/ |
| 3093 | |
| 3094 | #ifdef STAND_ALONE |
| 3095 | |
| 3096 | int main(int argc, char **cargv) |
| 3097 | { |
| 3098 | host_item h; |
| 3099 | int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A; |
| 3100 | BOOL byname = FALSE; |
| 3101 | BOOL qualify_single = TRUE; |
| 3102 | BOOL search_parents = FALSE; |
| 3103 | BOOL request_dnssec = FALSE; |
| 3104 | BOOL require_dnssec = FALSE; |
| 3105 | uschar **argv = USS cargv; |
| 3106 | uschar buffer[256]; |
| 3107 | |
| 3108 | disable_ipv6 = FALSE; |
| 3109 | primary_hostname = US""; |
| 3110 | store_pool = POOL_MAIN; |
| 3111 | debug_selector = D_host_lookup|D_interface; |
| 3112 | debug_file = stdout; |
| 3113 | debug_fd = fileno(debug_file); |
| 3114 | |
| 3115 | printf("Exim stand-alone host functions test\n"); |
| 3116 | |
| 3117 | host_find_interfaces(); |
| 3118 | debug_selector = D_host_lookup | D_dns; |
| 3119 | |
| 3120 | if (argc > 1) primary_hostname = argv[1]; |
| 3121 | |
| 3122 | /* So that debug level changes can be done first */ |
| 3123 | |
| 3124 | dns_init(qualify_single, search_parents, FALSE); |
| 3125 | |
| 3126 | printf("Testing host lookup\n"); |
| 3127 | printf("> "); |
| 3128 | while (Ufgets(buffer, 256, stdin) != NULL) |
| 3129 | { |
| 3130 | int rc; |
| 3131 | int len = Ustrlen(buffer); |
| 3132 | uschar *fully_qualified_name; |
| 3133 | |
| 3134 | while (len > 0 && isspace(buffer[len-1])) len--; |
| 3135 | buffer[len] = 0; |
| 3136 | |
| 3137 | if (Ustrcmp(buffer, "q") == 0) break; |
| 3138 | |
| 3139 | if (Ustrcmp(buffer, "byname") == 0) byname = TRUE; |
| 3140 | else if (Ustrcmp(buffer, "no_byname") == 0) byname = FALSE; |
| 3141 | else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A; |
| 3142 | else if (Ustrcmp(buffer, "mx_only") == 0) whichrrs = HOST_FIND_BY_MX; |
| 3143 | else if (Ustrcmp(buffer, "srv_only") == 0) whichrrs = HOST_FIND_BY_SRV; |
| 3144 | else if (Ustrcmp(buffer, "srv+a") == 0) |
| 3145 | whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A; |
| 3146 | else if (Ustrcmp(buffer, "srv+mx") == 0) |
| 3147 | whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX; |
| 3148 | else if (Ustrcmp(buffer, "srv+mx+a") == 0) |
| 3149 | whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A; |
| 3150 | else if (Ustrcmp(buffer, "qualify_single") == 0) qualify_single = TRUE; |
| 3151 | else if (Ustrcmp(buffer, "no_qualify_single") == 0) qualify_single = FALSE; |
| 3152 | else if (Ustrcmp(buffer, "search_parents") == 0) search_parents = TRUE; |
| 3153 | else if (Ustrcmp(buffer, "no_search_parents") == 0) search_parents = FALSE; |
| 3154 | else if (Ustrcmp(buffer, "request_dnssec") == 0) request_dnssec = TRUE; |
| 3155 | else if (Ustrcmp(buffer, "no_request_dnssec") == 0) request_dnssec = FALSE; |
| 3156 | else if (Ustrcmp(buffer, "require_dnssec") == 0) require_dnssec = TRUE; |
| 3157 | else if (Ustrcmp(buffer, "no_reqiret_dnssec") == 0) require_dnssec = FALSE; |
| 3158 | else if (Ustrcmp(buffer, "test_harness") == 0) |
| 3159 | running_in_test_harness = !running_in_test_harness; |
| 3160 | else if (Ustrcmp(buffer, "ipv6") == 0) disable_ipv6 = !disable_ipv6; |
| 3161 | else if (Ustrcmp(buffer, "res_debug") == 0) |
| 3162 | { |
| 3163 | _res.options ^= RES_DEBUG; |
| 3164 | } |
| 3165 | else if (Ustrncmp(buffer, "retrans", 7) == 0) |
| 3166 | { |
| 3167 | (void)sscanf(CS(buffer+8), "%d", &dns_retrans); |
| 3168 | _res.retrans = dns_retrans; |
| 3169 | } |
| 3170 | else if (Ustrncmp(buffer, "retry", 5) == 0) |
| 3171 | { |
| 3172 | (void)sscanf(CS(buffer+6), "%d", &dns_retry); |
| 3173 | _res.retry = dns_retry; |
| 3174 | } |
| 3175 | else |
| 3176 | { |
| 3177 | int flags = whichrrs; |
| 3178 | |
| 3179 | h.name = buffer; |
| 3180 | h.next = NULL; |
| 3181 | h.mx = MX_NONE; |
| 3182 | h.port = PORT_NONE; |
| 3183 | h.status = hstatus_unknown; |
| 3184 | h.why = hwhy_unknown; |
| 3185 | h.address = NULL; |
| 3186 | |
| 3187 | if (qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE; |
| 3188 | if (search_parents) flags |= HOST_FIND_SEARCH_PARENTS; |
| 3189 | |
| 3190 | rc = byname |
| 3191 | ? host_find_byname(&h, NULL, flags, &fully_qualified_name, TRUE) |
| 3192 | : host_find_bydns(&h, NULL, flags, US"smtp", NULL, NULL, |
| 3193 | request_dnssec ? &h.name : NULL, |
| 3194 | require_dnssec ? &h.name : NULL, |
| 3195 | &fully_qualified_name, NULL); |
| 3196 | |
| 3197 | if (rc == HOST_FIND_FAILED) printf("Failed\n"); |
| 3198 | else if (rc == HOST_FIND_AGAIN) printf("Again\n"); |
| 3199 | else if (rc == HOST_FOUND_LOCAL) printf("Local\n"); |
| 3200 | } |
| 3201 | |
| 3202 | printf("\n> "); |
| 3203 | } |
| 3204 | |
| 3205 | printf("Testing host_aton\n"); |
| 3206 | printf("> "); |
| 3207 | while (Ufgets(buffer, 256, stdin) != NULL) |
| 3208 | { |
| 3209 | int i; |
| 3210 | int x[4]; |
| 3211 | int len = Ustrlen(buffer); |
| 3212 | |
| 3213 | while (len > 0 && isspace(buffer[len-1])) len--; |
| 3214 | buffer[len] = 0; |
| 3215 | |
| 3216 | if (Ustrcmp(buffer, "q") == 0) break; |
| 3217 | |
| 3218 | len = host_aton(buffer, x); |
| 3219 | printf("length = %d ", len); |
| 3220 | for (i = 0; i < len; i++) |
| 3221 | { |
| 3222 | printf("%04x ", (x[i] >> 16) & 0xffff); |
| 3223 | printf("%04x ", x[i] & 0xffff); |
| 3224 | } |
| 3225 | printf("\n> "); |
| 3226 | } |
| 3227 | |
| 3228 | printf("\n"); |
| 3229 | |
| 3230 | printf("Testing host_name_lookup\n"); |
| 3231 | printf("> "); |
| 3232 | while (Ufgets(buffer, 256, stdin) != NULL) |
| 3233 | { |
| 3234 | int len = Ustrlen(buffer); |
| 3235 | while (len > 0 && isspace(buffer[len-1])) len--; |
| 3236 | buffer[len] = 0; |
| 3237 | if (Ustrcmp(buffer, "q") == 0) break; |
| 3238 | sender_host_address = buffer; |
| 3239 | sender_host_name = NULL; |
| 3240 | sender_host_aliases = NULL; |
| 3241 | host_lookup_msg = US""; |
| 3242 | host_lookup_failed = FALSE; |
| 3243 | if (host_name_lookup() == FAIL) /* Debug causes printing */ |
| 3244 | printf("Lookup failed:%s\n", host_lookup_msg); |
| 3245 | printf("\n> "); |
| 3246 | } |
| 3247 | |
| 3248 | printf("\n"); |
| 3249 | |
| 3250 | return 0; |
| 3251 | } |
| 3252 | #endif /* STAND_ALONE */ |
| 3253 | |
| 3254 | /* vi: aw ai sw=2 |
| 3255 | */ |
| 3256 | /* End of host.c */ |