| 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 | #include "../exim.h" |
| 9 | #include "lf_functions.h" |
| 10 | |
| 11 | /* Codes for the different kinds of lsearch that are supported */ |
| 12 | |
| 13 | enum { |
| 14 | LSEARCH_PLAIN, /* Literal keys */ |
| 15 | LSEARCH_WILD, /* Wild card keys, expanded */ |
| 16 | LSEARCH_NWILD, /* Wild card keys, not expanded */ |
| 17 | LSEARCH_IP /* IP addresses and networks */ |
| 18 | }; |
| 19 | |
| 20 | |
| 21 | |
| 22 | /************************************************* |
| 23 | * Open entry point * |
| 24 | *************************************************/ |
| 25 | |
| 26 | /* See local README for interface description */ |
| 27 | |
| 28 | static void * |
| 29 | lsearch_open(const uschar * filename, uschar ** errmsg) |
| 30 | { |
| 31 | FILE *f = Ufopen(filename, "rb"); |
| 32 | if (f == NULL) |
| 33 | { |
| 34 | int save_errno = errno; |
| 35 | *errmsg = string_open_failed(errno, "%s for linear search", filename); |
| 36 | errno = save_errno; |
| 37 | return NULL; |
| 38 | } |
| 39 | return f; |
| 40 | } |
| 41 | |
| 42 | |
| 43 | |
| 44 | /************************************************* |
| 45 | * Check entry point * |
| 46 | *************************************************/ |
| 47 | |
| 48 | static BOOL |
| 49 | lsearch_check(void *handle, const uschar *filename, int modemask, uid_t *owners, |
| 50 | gid_t *owngroups, uschar **errmsg) |
| 51 | { |
| 52 | return lf_check_file(fileno((FILE *)handle), filename, S_IFREG, modemask, |
| 53 | owners, owngroups, "lsearch", errmsg) == 0; |
| 54 | } |
| 55 | |
| 56 | |
| 57 | |
| 58 | /************************************************* |
| 59 | * Internal function for the various lsearches * |
| 60 | *************************************************/ |
| 61 | |
| 62 | /* See local README for interface description, plus: |
| 63 | |
| 64 | Extra argument: |
| 65 | |
| 66 | type one of the values LSEARCH_PLAIN, LSEARCH_WILD, LSEARCH_NWILD, or |
| 67 | LSEARCH_IP |
| 68 | |
| 69 | There is some messy logic in here to cope with very long data lines that do not |
| 70 | fit into the fixed sized buffer. Most of the time this will never be exercised, |
| 71 | but people do occasionally do weird things. */ |
| 72 | |
| 73 | static int |
| 74 | internal_lsearch_find(void * handle, const uschar * filename, |
| 75 | const uschar * keystring, int length, uschar ** result, uschar ** errmsg, |
| 76 | int type) |
| 77 | { |
| 78 | FILE *f = (FILE *)handle; |
| 79 | BOOL last_was_eol = TRUE; |
| 80 | BOOL this_is_eol = TRUE; |
| 81 | int old_pool = store_pool; |
| 82 | rmark reset_point = NULL; |
| 83 | uschar buffer[4096]; |
| 84 | |
| 85 | /* Wildcard searches may use up some store, because of expansions. We don't |
| 86 | want them to fill up our search store. What we do is set the pool to the main |
| 87 | pool and get a point to reset to later. Wildcard searches could also issue |
| 88 | lookups, but internal_search_find will take care of that, and the cache will be |
| 89 | safely stored in the search pool again. */ |
| 90 | |
| 91 | if(type == LSEARCH_WILD || type == LSEARCH_NWILD) |
| 92 | { |
| 93 | store_pool = POOL_MAIN; |
| 94 | reset_point = store_mark(); |
| 95 | } |
| 96 | |
| 97 | filename = filename; /* Keep picky compilers happy */ |
| 98 | errmsg = errmsg; |
| 99 | |
| 100 | rewind(f); |
| 101 | for (last_was_eol = TRUE; |
| 102 | Ufgets(buffer, sizeof(buffer), f) != NULL; |
| 103 | last_was_eol = this_is_eol) |
| 104 | { |
| 105 | int p = Ustrlen(buffer); |
| 106 | int linekeylength; |
| 107 | BOOL this_is_comment; |
| 108 | gstring * yield; |
| 109 | uschar *s = buffer; |
| 110 | |
| 111 | /* Check whether this the final segment of a line. If it follows an |
| 112 | incomplete part-line, skip it. */ |
| 113 | |
| 114 | this_is_eol = p > 0 && buffer[p-1] == '\n'; |
| 115 | if (!last_was_eol) continue; |
| 116 | |
| 117 | /* We now have the start of a physical line. If this is a final line segment, |
| 118 | remove trailing white space. */ |
| 119 | |
| 120 | if (this_is_eol) |
| 121 | { |
| 122 | while (p > 0 && isspace((uschar)buffer[p-1])) p--; |
| 123 | buffer[p] = 0; |
| 124 | } |
| 125 | |
| 126 | /* If the buffer is empty it might be (a) a complete empty line, or (b) the |
| 127 | start of a line that begins with so much white space that it doesn't all fit |
| 128 | in the buffer. In both cases we want to skip the entire physical line. |
| 129 | |
| 130 | If the buffer begins with # it is a comment line; if it begins with white |
| 131 | space it is a logical continuation; again, we want to skip the entire |
| 132 | physical line. */ |
| 133 | |
| 134 | if (buffer[0] == 0 || buffer[0] == '#' || isspace(buffer[0])) continue; |
| 135 | |
| 136 | /* We assume that they key will fit in the buffer. If the key starts with ", |
| 137 | read it as a quoted string. We don't use string_dequote() because that uses |
| 138 | new store for the result, and we may be doing this many times in a long file. |
| 139 | We know that the dequoted string must be shorter than the original, because |
| 140 | we are removing the quotes, and also any escape sequences always turn two or |
| 141 | more characters into one character. Therefore, we can store the new string in |
| 142 | the same buffer. */ |
| 143 | |
| 144 | if (*s == '\"') |
| 145 | { |
| 146 | uschar *t = s++; |
| 147 | while (*s != 0 && *s != '\"') |
| 148 | { |
| 149 | if (*s == '\\') *t++ = string_interpret_escape(CUSS &s); |
| 150 | else *t++ = *s; |
| 151 | s++; |
| 152 | } |
| 153 | if (*s != 0) s++; /* Past terminating " */ |
| 154 | linekeylength = t - buffer; |
| 155 | } |
| 156 | |
| 157 | /* Otherwise it is terminated by a colon or white space */ |
| 158 | |
| 159 | else |
| 160 | { |
| 161 | while (*s != 0 && *s != ':' && !isspace(*s)) s++; |
| 162 | linekeylength = s - buffer; |
| 163 | } |
| 164 | |
| 165 | /* The matching test depends on which kind of lsearch we are doing */ |
| 166 | |
| 167 | switch(type) |
| 168 | { |
| 169 | /* A plain lsearch treats each key as a literal */ |
| 170 | |
| 171 | case LSEARCH_PLAIN: |
| 172 | if (linekeylength != length || strncmpic(buffer, keystring, length) != 0) |
| 173 | continue; |
| 174 | break; /* Key matched */ |
| 175 | |
| 176 | /* A wild lsearch treats each key as a possible wildcarded string; no |
| 177 | expansion is done for nwildlsearch. */ |
| 178 | |
| 179 | case LSEARCH_WILD: |
| 180 | case LSEARCH_NWILD: |
| 181 | { |
| 182 | int rc; |
| 183 | int save = buffer[linekeylength]; |
| 184 | const uschar *list = buffer; |
| 185 | buffer[linekeylength] = 0; |
| 186 | rc = match_isinlist(keystring, |
| 187 | &list, |
| 188 | UCHAR_MAX+1, /* Single-item list */ |
| 189 | NULL, /* No anchor */ |
| 190 | NULL, /* No caching */ |
| 191 | MCL_STRING + ((type == LSEARCH_WILD)? 0:MCL_NOEXPAND), |
| 192 | TRUE, /* Caseless */ |
| 193 | NULL); |
| 194 | buffer[linekeylength] = save; |
| 195 | if (rc == FAIL) continue; |
| 196 | if (rc == DEFER) return DEFER; |
| 197 | } |
| 198 | |
| 199 | /* The key has matched. If the search involved a regular expression, it |
| 200 | might have caused numerical variables to be set. However, their values will |
| 201 | be in the wrong storage pool for external use. Copying them to the standard |
| 202 | pool is not feasible because of the caching of lookup results - a repeated |
| 203 | lookup will not match the regular expression again. Therefore, we flatten |
| 204 | all numeric variables at this point. */ |
| 205 | |
| 206 | expand_nmax = -1; |
| 207 | break; |
| 208 | |
| 209 | /* Compare an ip address against a list of network/ip addresses. We have to |
| 210 | allow for the "*" case specially. */ |
| 211 | |
| 212 | case LSEARCH_IP: |
| 213 | if (linekeylength == 1 && buffer[0] == '*') |
| 214 | { |
| 215 | if (length != 1 || keystring[0] != '*') continue; |
| 216 | } |
| 217 | else if (length == 1 && keystring[0] == '*') continue; |
| 218 | else |
| 219 | { |
| 220 | int maskoffset; |
| 221 | int save = buffer[linekeylength]; |
| 222 | buffer[linekeylength] = 0; |
| 223 | if (string_is_ip_address(buffer, &maskoffset) == 0 || |
| 224 | !host_is_in_net(keystring, buffer, maskoffset)) continue; |
| 225 | buffer[linekeylength] = save; |
| 226 | } |
| 227 | break; /* Key matched */ |
| 228 | } |
| 229 | |
| 230 | /* The key has matched. Skip spaces after the key, and allow an optional |
| 231 | colon after the spaces. This is an odd specification, but it's for |
| 232 | compatibility. */ |
| 233 | |
| 234 | while (isspace((uschar)*s)) s++; |
| 235 | if (*s == ':') |
| 236 | { |
| 237 | s++; |
| 238 | while (isspace((uschar)*s)) s++; |
| 239 | } |
| 240 | |
| 241 | /* Reset dynamic store, if we need to, and revert to the search pool */ |
| 242 | |
| 243 | if (reset_point) |
| 244 | { |
| 245 | reset_point = store_reset(reset_point); |
| 246 | store_pool = old_pool; |
| 247 | } |
| 248 | |
| 249 | /* Now we want to build the result string to contain the data. There can be |
| 250 | two kinds of continuation: (a) the physical line may not all have fitted into |
| 251 | the buffer, and (b) there may be logical continuation lines, for which we |
| 252 | must convert all leading white space into a single blank. |
| 253 | |
| 254 | Initialize, and copy the first segment of data. */ |
| 255 | |
| 256 | this_is_comment = FALSE; |
| 257 | yield = string_get(100); |
| 258 | if (*s != 0) |
| 259 | yield = string_cat(yield, s); |
| 260 | |
| 261 | /* Now handle continuations */ |
| 262 | |
| 263 | for (last_was_eol = this_is_eol; |
| 264 | Ufgets(buffer, sizeof(buffer), f) != NULL; |
| 265 | last_was_eol = this_is_eol) |
| 266 | { |
| 267 | s = buffer; |
| 268 | p = Ustrlen(buffer); |
| 269 | this_is_eol = p > 0 && buffer[p-1] == '\n'; |
| 270 | |
| 271 | /* Remove trailing white space from a physical line end */ |
| 272 | |
| 273 | if (this_is_eol) |
| 274 | { |
| 275 | while (p > 0 && isspace((uschar)buffer[p-1])) p--; |
| 276 | buffer[p] = 0; |
| 277 | } |
| 278 | |
| 279 | /* If this is not a physical line continuation, skip it entirely if it's |
| 280 | empty or starts with #. Otherwise, break the loop if it doesn't start with |
| 281 | white space. Otherwise, replace leading white space with a single blank. */ |
| 282 | |
| 283 | if (last_was_eol) |
| 284 | { |
| 285 | this_is_comment = (this_is_comment || (buffer[0] == 0 || buffer[0] == '#')); |
| 286 | if (this_is_comment) continue; |
| 287 | if (!isspace((uschar)buffer[0])) break; |
| 288 | while (isspace((uschar)*s)) s++; |
| 289 | *(--s) = ' '; |
| 290 | } |
| 291 | if (this_is_comment) continue; |
| 292 | |
| 293 | /* Join a physical or logical line continuation onto the result string. */ |
| 294 | |
| 295 | yield = string_cat(yield, s); |
| 296 | } |
| 297 | |
| 298 | gstring_release_unused(yield); |
| 299 | *result = string_from_gstring(yield); |
| 300 | return OK; |
| 301 | } |
| 302 | |
| 303 | /* Reset dynamic store, if we need to */ |
| 304 | |
| 305 | if (reset_point) |
| 306 | { |
| 307 | store_reset(reset_point); |
| 308 | store_pool = old_pool; |
| 309 | } |
| 310 | |
| 311 | return FAIL; |
| 312 | } |
| 313 | |
| 314 | |
| 315 | /************************************************* |
| 316 | * Find entry point for lsearch * |
| 317 | *************************************************/ |
| 318 | |
| 319 | /* See local README for interface description */ |
| 320 | |
| 321 | static int |
| 322 | lsearch_find(void * handle, const uschar * filename, const uschar * keystring, |
| 323 | int length, uschar ** result, uschar ** errmsg, uint * do_cache, |
| 324 | const uschar * opts) |
| 325 | { |
| 326 | do_cache = do_cache; /* Keep picky compilers happy */ |
| 327 | return internal_lsearch_find(handle, filename, keystring, length, result, |
| 328 | errmsg, LSEARCH_PLAIN); |
| 329 | } |
| 330 | |
| 331 | |
| 332 | |
| 333 | /************************************************* |
| 334 | * Find entry point for wildlsearch * |
| 335 | *************************************************/ |
| 336 | |
| 337 | /* See local README for interface description */ |
| 338 | |
| 339 | static int |
| 340 | wildlsearch_find(void * handle, const uschar * filename, const uschar * keystring, |
| 341 | int length, uschar ** result, uschar ** errmsg, uint * do_cache, |
| 342 | const uschar * opts) |
| 343 | { |
| 344 | do_cache = do_cache; /* Keep picky compilers happy */ |
| 345 | return internal_lsearch_find(handle, filename, keystring, length, result, |
| 346 | errmsg, LSEARCH_WILD); |
| 347 | } |
| 348 | |
| 349 | |
| 350 | |
| 351 | /************************************************* |
| 352 | * Find entry point for nwildlsearch * |
| 353 | *************************************************/ |
| 354 | |
| 355 | /* See local README for interface description */ |
| 356 | |
| 357 | static int |
| 358 | nwildlsearch_find(void * handle, const uschar * filename, const uschar * keystring, |
| 359 | int length, uschar ** result, uschar ** errmsg, uint * do_cache, |
| 360 | const uschar * opts) |
| 361 | { |
| 362 | do_cache = do_cache; /* Keep picky compilers happy */ |
| 363 | return internal_lsearch_find(handle, filename, keystring, length, result, |
| 364 | errmsg, LSEARCH_NWILD); |
| 365 | } |
| 366 | |
| 367 | |
| 368 | |
| 369 | |
| 370 | /************************************************* |
| 371 | * Find entry point for iplsearch * |
| 372 | *************************************************/ |
| 373 | |
| 374 | /* See local README for interface description */ |
| 375 | |
| 376 | static int |
| 377 | iplsearch_find(void * handle, uschar const * filename, const uschar * keystring, |
| 378 | int length, uschar ** result, uschar ** errmsg, uint * do_cache, |
| 379 | const uschar * opts) |
| 380 | { |
| 381 | do_cache = do_cache; /* Keep picky compilers happy */ |
| 382 | |
| 383 | if ((length == 1 && keystring[0] == '*') || |
| 384 | string_is_ip_address(keystring, NULL) != 0) |
| 385 | return internal_lsearch_find(handle, filename, keystring, length, result, |
| 386 | errmsg, LSEARCH_IP); |
| 387 | |
| 388 | *errmsg = string_sprintf("\"%s\" is not a valid iplsearch key (an IP " |
| 389 | "address, with optional CIDR mask, is wanted): " |
| 390 | "in a host list, use net-iplsearch as the search type", keystring); |
| 391 | return DEFER; |
| 392 | } |
| 393 | |
| 394 | |
| 395 | |
| 396 | |
| 397 | /************************************************* |
| 398 | * Close entry point * |
| 399 | *************************************************/ |
| 400 | |
| 401 | /* See local README for interface description */ |
| 402 | |
| 403 | static void |
| 404 | lsearch_close(void *handle) |
| 405 | { |
| 406 | (void)fclose((FILE *)handle); |
| 407 | } |
| 408 | |
| 409 | |
| 410 | |
| 411 | /************************************************* |
| 412 | * Version reporting entry point * |
| 413 | *************************************************/ |
| 414 | |
| 415 | /* See local README for interface description. */ |
| 416 | |
| 417 | #include "../version.h" |
| 418 | |
| 419 | void |
| 420 | lsearch_version_report(FILE *f) |
| 421 | { |
| 422 | #ifdef DYNLOOKUP |
| 423 | fprintf(f, "Library version: lsearch: Exim version %s\n", EXIM_VERSION_STR); |
| 424 | #endif |
| 425 | } |
| 426 | |
| 427 | |
| 428 | static lookup_info iplsearch_lookup_info = { |
| 429 | .name = US"iplsearch", /* lookup name */ |
| 430 | .type = lookup_absfile, /* uses absolute file name */ |
| 431 | .open = lsearch_open, /* open function */ |
| 432 | .check = lsearch_check, /* check function */ |
| 433 | .find = iplsearch_find, /* find function */ |
| 434 | .close = lsearch_close, /* close function */ |
| 435 | .tidy = NULL, /* no tidy function */ |
| 436 | .quote = NULL, /* no quoting function */ |
| 437 | .version_report = NULL /* no version reporting (redundant) */ |
| 438 | }; |
| 439 | |
| 440 | static lookup_info lsearch_lookup_info = { |
| 441 | .name = US"lsearch", /* lookup name */ |
| 442 | .type = lookup_absfile, /* uses absolute file name */ |
| 443 | .open = lsearch_open, /* open function */ |
| 444 | .check = lsearch_check, /* check function */ |
| 445 | .find = lsearch_find, /* find function */ |
| 446 | .close = lsearch_close, /* close function */ |
| 447 | .tidy = NULL, /* no tidy function */ |
| 448 | .quote = NULL, /* no quoting function */ |
| 449 | .version_report = lsearch_version_report /* version reporting */ |
| 450 | }; |
| 451 | |
| 452 | static lookup_info nwildlsearch_lookup_info = { |
| 453 | .name = US"nwildlsearch", /* lookup name */ |
| 454 | .type = lookup_absfile, /* uses absolute file name */ |
| 455 | .open = lsearch_open, /* open function */ |
| 456 | .check = lsearch_check, /* check function */ |
| 457 | .find = nwildlsearch_find, /* find function */ |
| 458 | .close = lsearch_close, /* close function */ |
| 459 | .tidy = NULL, /* no tidy function */ |
| 460 | .quote = NULL, /* no quoting function */ |
| 461 | .version_report = NULL /* no version reporting (redundant) */ |
| 462 | }; |
| 463 | |
| 464 | static lookup_info wildlsearch_lookup_info = { |
| 465 | .name = US"wildlsearch", /* lookup name */ |
| 466 | .type = lookup_absfile, /* uses absolute file name */ |
| 467 | .open = lsearch_open, /* open function */ |
| 468 | .check = lsearch_check, /* check function */ |
| 469 | .find = wildlsearch_find, /* find function */ |
| 470 | .close = lsearch_close, /* close function */ |
| 471 | .tidy = NULL, /* no tidy function */ |
| 472 | .quote = NULL, /* no quoting function */ |
| 473 | .version_report = NULL /* no version reporting (redundant) */ |
| 474 | }; |
| 475 | |
| 476 | #ifdef DYNLOOKUP |
| 477 | #define lsearch_lookup_module_info _lookup_module_info |
| 478 | #endif |
| 479 | |
| 480 | static lookup_info *_lookup_list[] = { &iplsearch_lookup_info, |
| 481 | &lsearch_lookup_info, |
| 482 | &nwildlsearch_lookup_info, |
| 483 | &wildlsearch_lookup_info }; |
| 484 | lookup_module_info lsearch_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 4 }; |
| 485 | |
| 486 | /* End of lookups/lsearch.c */ |