src/routers/manualroute.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 #include "../exim.h"
  10 #include "rf_functions.h"
  11 #include "manualroute.h"
  12
  13
  14 /* Options specific to the manualroute router. */
  15
  16 optionlist manualroute_router_options[] = {
  17   { "host_all_ignored", opt_stringptr,
  18       (void *)(offsetof(manualroute_router_options_block, host_all_ignored)) },
  19   { "host_find_failed", opt_stringptr,
  20       (void *)(offsetof(manualroute_router_options_block, host_find_failed)) },
  21   { "hosts_randomize",  opt_bool,
  22       (void *)(offsetof(manualroute_router_options_block, hosts_randomize)) },
  23   { "route_data",       opt_stringptr,
  24       (void *)(offsetof(manualroute_router_options_block, route_data)) },
  25   { "route_list",       opt_stringptr,
  26       (void *)(offsetof(manualroute_router_options_block, route_list)) },
  27   { "same_domain_copy_routing", opt_bool|opt_public,
  28       (void *)(offsetof(router_instance, same_domain_copy_routing)) }
  29 };
  30
  31 /* Size of the options list. An extern variable has to be used so that its
  32 address can appear in the tables drtables.c. */
  33
  34 int manualroute_router_options_count =
  35   sizeof(manualroute_router_options)/sizeof(optionlist);
  36
  37
  38 #ifdef MACRO_PREDEF
  39
  40 /* Dummy entries */
  41 manualroute_router_options_block manualroute_router_option_defaults = {0};
  42 void manualroute_router_init(router_instance *rblock) {}
  43 int manualroute_router_entry(router_instance *rblock, address_item *addr,
  44   struct passwd *pw, int verify, address_item **addr_local,
  45   address_item **addr_remote, address_item **addr_new,
  46   address_item **addr_succeed) {return 0;}
  47
  48 #else   /*!MACRO_PREDEF*/
  49
  50
  51
  52 /* Default private options block for the manualroute router. */
  53
  54 manualroute_router_options_block manualroute_router_option_defaults = {
  55   -1,           /* host_all_ignored code (unset) */
  56   -1,           /* host_find_failed code (unset) */
  57   FALSE,        /* hosts_randomize */
  58   US"defer",    /* host_all_ignored */
  59   US"freeze",   /* host_find_failed */
  60   NULL,         /* route_data */
  61   NULL          /* route_list */
  62 };
  63
  64
  65 /* Names and values for host_find_failed and host_all_ignored.  */
  66
  67 static uschar *hff_names[] = {
  68   US"ignore",  /* MUST be first - not valid for host_all_ignored */
  69   US"decline",
  70   US"defer",
  71   US"fail",
  72   US"freeze",
  73   US"pass" };
  74
  75 static int hff_codes[] = { hff_ignore, hff_decline, hff_defer, hff_fail,
  76   hff_freeze, hff_pass };
  77
  78 static int hff_count= sizeof(hff_codes)/sizeof(int);
  79
  80
  81
  82 /*************************************************
  83 *          Initialization entry point            *
  84 *************************************************/
  85
  86 /* Called for each instance, after its options have been read, to enable
  87 consistency checks to be done, or anything else that needs to be set up. */
  88
  89 void
  90 manualroute_router_init(router_instance *rblock)
  91 {
  92 manualroute_router_options_block *ob =
  93   (manualroute_router_options_block *)(rblock->options_block);
  94 int i;
  95
  96 /* Host_find_failed must be a recognized word */
  97
  98 for (i = 0; i < hff_count; i++)
  99   {
 100   if (Ustrcmp(ob->host_find_failed, hff_names[i]) == 0)
 101     {
 102     ob->hff_code = hff_codes[i];
 103     break;
 104     }
 105   }
 106 if (ob->hff_code < 0)
 107   log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s router:\n  "
 108     "unrecognized setting for host_find_failed option", rblock->name);
 109
 110 for (i = 1; i < hff_count; i++)   /* NB starts at 1 to skip "ignore" */
 111   {
 112   if (Ustrcmp(ob->host_all_ignored, hff_names[i]) == 0)
 113     {
 114     ob->hai_code = hff_codes[i];
 115     break;
 116     }
 117   }
 118 if (ob->hai_code < 0)
 119   log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s router:\n  "
 120     "unrecognized setting for host_all_ignored option", rblock->name);
 121
 122 /* One of route_list or route_data must be specified */
 123
 124 if ((ob->route_list == NULL && ob->route_data == NULL) ||
 125     (ob->route_list != NULL && ob->route_data != NULL))
 126   log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s router:\n  "
 127     "route_list or route_data (but not both) must be specified",
 128     rblock->name);
 129 }
 130
 131
 132
 133
 134 /*************************************************
 135 *               Parse a route item               *
 136 *************************************************/
 137
 138 /* The format of a route list item is:
 139
 140   <domain> [<host[list]> [<options>]]
 141
 142 if obtained from route_list. The domain is absent if the string came from
 143 route_data, in which case domain==NULL. The domain and the host list may be
 144 enclosed in quotes.
 145
 146 Arguments:
 147   s         pointer to route list item
 148   domain    if not NULL, where to put the domain pointer
 149   hostlist  where to put the host[list] pointer
 150   options   where to put the options pointer
 151
 152 Returns:    FALSE if domain expected and string is empty;
 153             TRUE otherwise
 154 */
 155
 156 static BOOL
 157 parse_route_item(const uschar *s, const uschar **domain, const uschar **hostlist,
 158   const uschar **options)
 159 {
 160 while (*s != 0 && isspace(*s)) s++;
 161
 162 if (domain)
 163   {
 164   if (!*s) return FALSE;            /* missing data */
 165   *domain = string_dequote(&s);
 166   while (*s && isspace(*s)) s++;
 167   }
 168
 169 *hostlist = string_dequote(&s);
 170 while (*s && isspace(*s)) s++;
 171 *options = s;
 172 return TRUE;
 173 }
 174
 175
 176
 177 /*************************************************
 178 *              Main entry point                  *
 179 *************************************************/
 180
 181 /* The manualroute router provides a manual routing facility (surprise,
 182 surprise). The data that defines the routing can either be set in route_data
 183 (which means it can be found by, for example, looking up the domain in a file),
 184 or a list of domain patterns and their corresponding data can be provided in
 185 route_list. */
 186
 187 /* See local README for interface details. This router returns:
 188
 189 DECLINE
 190   . no pattern in route_list matched (route_data not set)
 191   . route_data was an empty string (route_list not set)
 192   . forced expansion failure in route_data (rf_expand_data)
 193   . forced expansion of host list
 194   . host_find_failed = decline
 195
 196 DEFER
 197   . transport not defined when needed
 198   . lookup defer in route_list when matching domain pattern
 199   . non-forced expansion failure in route_data
 200   . non-forced expansion failure in host list
 201   . unknown routing option
 202   . host list missing for remote transport (not verifying)
 203   . timeout etc on host lookup (pass_on_timeout not set)
 204   . verifying the errors address caused a deferment or a big disaster such
 205       as an expansion failure (rf_get_errors_address)
 206   . expanding a headers_{add,remove} string caused a deferment or another
 207       expansion error (rf_get_munge_headers)
 208   . a problem in rf_get_transport: no transport when one is needed;
 209       failed to expand dynamic transport; failed to find dynamic transport
 210   . failure to expand or find a uid/gid (rf_get_ugid via rf_queue_add)
 211   . host_find_failed = freeze or defer
 212   . self = freeze or defer
 213
 214 PASS
 215   . timeout etc on host lookup (pass_on_timeout set)
 216   . host_find_failed = pass
 217   . self = pass
 218
 219 REROUTED
 220   . self = reroute
 221
 222 FAIL
 223   . host_find_failed = fail
 224   . self = fail
 225
 226 OK
 227   . added address to addr_local or addr_remote, as appropriate for the
 228     type of transport; this includes the self="send" case.
 229 */
 230
 231 int
 232 manualroute_router_entry(
 233   router_instance *rblock,        /* data for this instantiation */
 234   address_item *addr,             /* address we are working on */
 235   struct passwd *pw,              /* passwd entry after check_local_user */
 236   int verify,                     /* v_none/v_recipient/v_sender/v_expn */
 237   address_item **addr_local,      /* add it to this if it's local */
 238   address_item **addr_remote,     /* add it to this if it's remote */
 239   address_item **addr_new,        /* put new addresses on here */
 240   address_item **addr_succeed)    /* put old address here on success */
 241 {
 242 int rc, lookup_type;
 243 uschar *route_item = NULL;
 244 const uschar *options = NULL;
 245 const uschar *hostlist = NULL;
 246 const uschar *domain;
 247 uschar *newhostlist;
 248 const uschar *listptr;
 249 manualroute_router_options_block *ob =
 250   (manualroute_router_options_block *)(rblock->options_block);
 251 transport_instance *transport = NULL;
 252 BOOL individual_transport_set = FALSE;
 253 BOOL randomize = ob->hosts_randomize;
 254
 255 addr_new = addr_new;           /* Keep picky compilers happy */
 256 addr_succeed = addr_succeed;
 257
 258 DEBUG(D_route) debug_printf("%s router called for %s\n  domain = %s\n",
 259   rblock->name, addr->address, addr->domain);
 260
 261 /* The initialization check ensures that either route_list or route_data is
 262 set. */
 263
 264 if (ob->route_list)
 265   {
 266   int sep = -(';');             /* Default is semicolon */
 267   listptr = ob->route_list;
 268
 269   while ((route_item = string_nextinlist(&listptr, &sep, NULL, 0)) != NULL)
 270     {
 271     int rc;
 272
 273     DEBUG(D_route) debug_printf("route_item = %s\n", route_item);
 274     if (!parse_route_item(route_item, &domain, &hostlist, &options))
 275       continue;     /* Ignore blank items */
 276
 277     /* Check the current domain; if it matches, break the loop */
 278
 279     if ((rc = match_isinlist(addr->domain, &domain, UCHAR_MAX+1,
 280            &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, CUSS &lookup_value)) == OK)
 281       break;
 282
 283     /* If there was a problem doing the check, defer */
 284
 285     if (rc == DEFER)
 286       {
 287       addr->message = US"lookup defer in route_list";
 288       return DEFER;
 289       }
 290     }
 291
 292   if (!route_item) return DECLINE;  /* No pattern in the list matched */
 293   }
 294
 295 /* Handle a single routing item in route_data. If it expands to an empty
 296 string, decline. */
 297
 298 else
 299   {
 300   if (!(route_item = rf_expand_data(addr, ob->route_data, &rc)))
 301     return rc;
 302   (void) parse_route_item(route_item, NULL, &hostlist, &options);
 303   if (!hostlist[0]) return DECLINE;
 304   }
 305
 306 /* Expand the hostlist item. It may then pointing to an empty string, or to a
 307 single host or a list of hosts; options is pointing to the rest of the
 308 routelist item, which is either empty or contains various option words. */
 309
 310 DEBUG(D_route) debug_printf("original list of hosts = '%s' options = '%s'\n",
 311   hostlist, options);
 312
 313 newhostlist = expand_string_copy(hostlist);
 314 lookup_value = NULL;                        /* Finished with */
 315 expand_nmax = -1;
 316
 317 /* If the expansion was forced to fail, just decline. Otherwise there is a
 318 configuration problem. */
 319
 320 if (!newhostlist)
 321   {
 322   if (f.expand_string_forcedfail) return DECLINE;
 323   addr->message = string_sprintf("%s router: failed to expand \"%s\": %s",
 324     rblock->name, hostlist, expand_string_message);
 325   return DEFER;
 326   }
 327 else hostlist = newhostlist;
 328
 329 DEBUG(D_route) debug_printf("expanded list of hosts = '%s' options = '%s'\n",
 330   hostlist, options);
 331
 332 /* Set default lookup type and scan the options */
 333
 334 lookup_type = LK_DEFAULT;
 335
 336 while (*options)
 337   {
 338   unsigned n;
 339   const uschar *s = options;
 340   while (*options != 0 && !isspace(*options)) options++;
 341   n = options-s;
 342
 343   if (Ustrncmp(s, "randomize", n) == 0) randomize = TRUE;
 344   else if (Ustrncmp(s, "no_randomize", n) == 0) randomize = FALSE;
 345   else if (Ustrncmp(s, "byname", n) == 0)
 346     lookup_type = lookup_type & ~(LK_DEFAULT | LK_BYDNS) | LK_BYNAME;
 347   else if (Ustrncmp(s, "bydns", n) == 0)
 348     lookup_type = lookup_type & ~(LK_DEFAULT | LK_BYNAME) & LK_BYDNS;
 349   else if (Ustrncmp(s, "ipv4_prefer", n) == 0) lookup_type |= LK_IPV4_PREFER;
 350   else if (Ustrncmp(s, "ipv4_only",   n) == 0) lookup_type |= LK_IPV4_ONLY;
 351   else
 352     {
 353     transport_instance *t;
 354     for (t = transports; t; t = t->next)
 355       if (Ustrncmp(t->name, s, n) == 0)
 356         {
 357         transport = t;
 358         individual_transport_set = TRUE;
 359         break;
 360         }
 361
 362     if (!t)
 363       {
 364       s = string_sprintf("unknown routing option or transport name \"%s\"", s);
 365       log_write(0, LOG_MAIN, "Error in %s router: %s", rblock->name, s);
 366       addr->message = string_sprintf("error in router: %s", s);
 367       return DEFER;
 368       }
 369     }
 370
 371   if (*options)
 372     {
 373     options++;
 374     while (*options != 0 && isspace(*options)) options++;
 375     }
 376   }
 377
 378 /* Set up the errors address, if any. */
 379
 380 rc = rf_get_errors_address(addr, rblock, verify, &addr->prop.errors_address);
 381 if (rc != OK) return rc;
 382
 383 /* Set up the additional and removable headers for this address. */
 384
 385 rc = rf_get_munge_headers(addr, rblock, &addr->prop.extra_headers,
 386   &addr->prop.remove_headers);
 387 if (rc != OK) return rc;
 388
 389 /* If an individual transport is not set, get the transport for this router, if
 390 any. It might be expanded, or it might be unset if this router has verify_only
 391 set. */
 392
 393 if (!individual_transport_set)
 394   {
 395   if (!rf_get_transport(rblock->transport_name, &(rblock->transport), addr,
 396       rblock->name, NULL))
 397     return DEFER;
 398   transport = rblock->transport;
 399   }
 400
 401 /* Deal with the case of a local transport. The host list is passed over as a
 402 single text string that ends up in $host. */
 403
 404 if (transport && transport->info->local)
 405   {
 406   if (hostlist[0])
 407     {
 408     host_item *h;
 409     addr->host_list = h = store_get(sizeof(host_item));
 410     h->name = string_copy(hostlist);
 411     h->address = NULL;
 412     h->port = PORT_NONE;
 413     h->mx = MX_NONE;
 414     h->status = hstatus_unknown;
 415     h->why = hwhy_unknown;
 416     h->last_try = 0;
 417     h->next = NULL;
 418     }
 419
 420   /* There is nothing more to do other than to queue the address for the
 421   local transport, filling in any uid/gid. This can be done by the common
 422   rf_queue_add() function. */
 423
 424   addr->transport = transport;
 425   return rf_queue_add(addr, addr_local, addr_remote, rblock, pw)?
 426     OK : DEFER;
 427   }
 428
 429 /* There is either no transport (verify_only) or a remote transport. A host
 430 list is mandatory in either case, except when verifying, in which case the
 431 address is just accepted. */
 432
 433 if (!hostlist[0])
 434   {
 435   if (verify != v_none) goto ROUTED;
 436   addr->message = string_sprintf("error in %s router: no host(s) specified "
 437     "for domain %s", rblock->name, addr->domain);
 438   log_write(0, LOG_MAIN, "%s", addr->message);
 439   return DEFER;
 440   }
 441
 442 /* Otherwise we finish the routing here by building a chain of host items
 443 for the list of configured hosts, and then finding their addresses. */
 444
 445 host_build_hostlist(&addr->host_list, hostlist, randomize);
 446 rc = rf_lookup_hostlist(rblock, addr, rblock->ignore_target_hosts, lookup_type,
 447   ob->hff_code, addr_new);
 448 if (rc != OK) return rc;
 449
 450 /* If host_find_failed is set to "ignore", it is possible for all the hosts to
 451 be ignored, in which case we will end up with an empty host list. What happens
 452 is controlled by host_all_ignored. */
 453
 454 if (!addr->host_list)
 455   {
 456   int i;
 457   DEBUG(D_route) debug_printf("host_find_failed ignored every host\n");
 458   if (ob->hai_code == hff_decline) return DECLINE;
 459   if (ob->hai_code == hff_pass) return PASS;
 460
 461   for (i = 0; i < hff_count; i++)
 462     if (ob->hai_code == hff_codes[i]) break;
 463
 464   addr->message = string_sprintf("lookup failed for all hosts in %s router: "
 465     "host_find_failed=ignore host_all_ignored=%s", rblock->name, hff_names[i]);
 466
 467   if (ob->hai_code == hff_defer) return DEFER;
 468   if (ob->hai_code == hff_fail) return FAIL;
 469
 470   addr->special_action = SPECIAL_FREEZE;
 471   return DEFER;
 472   }
 473
 474 /* Finally, since we have done all the routing here, there must be a transport
 475 defined for these hosts. It will be a remote one, as a local transport is
 476 dealt with above. However, we don't need one if verifying only. */
 477
 478 if (transport == NULL && verify == v_none)
 479     {
 480     log_write(0, LOG_MAIN, "Error in %s router: no transport defined",
 481       rblock->name);
 482     addr->message = US"error in router: transport missing";
 483     return DEFER;
 484     }
 485
 486 /* Fill in the transport, queue for remote delivery. The yield of
 487 rf_queue_add() is always TRUE for a remote transport. */
 488
 489 ROUTED:
 490
 491 addr->transport = transport;
 492 (void)rf_queue_add(addr, addr_local, addr_remote, rblock, NULL);
 493 return OK;
 494 }
 495
 496 #endif   /*!MACRO_PREDEF*/
 497 /* End of routers/manualroute.c */