1 /* 2 ** Copyright (c) 1999-2002 Proofpoint, Inc. and its suppliers. 3 ** All rights reserved. 4 ** 5 ** By using this file, you agree to the terms and conditions set 6 ** forth in the LICENSE file which can be found at the top level of 7 ** the sendmail distribution. 8 */ 9 10 #include <sm/gen.h> 11 SM_RCSID("@(#)$Id: smdb.c,v 8.59 2013-11-22 20:51:49 ca Exp $") 12 13 #include <fcntl.h> 14 #include <stdlib.h> 15 #include <unistd.h> 16 17 18 #include <sendmail/sendmail.h> 19 #include <libsmdb/smdb.h> 20 21 static bool smdb_lockfile __P((int, int)); 22 23 /* 24 ** SMDB_MALLOC_DATABASE -- Allocates a database structure. 25 ** 26 ** Parameters: 27 ** None 28 ** 29 ** Returns: 30 ** A pointer to an allocated SMDB_DATABASE structure or 31 ** NULL if it couldn't allocate the memory. 32 */ 33 34 SMDB_DATABASE * 35 smdb_malloc_database() 36 { 37 SMDB_DATABASE *db; 38 39 db = (SMDB_DATABASE *) malloc(sizeof(SMDB_DATABASE)); 40 41 if (db != NULL) 42 (void) memset(db, '\0', sizeof(SMDB_DATABASE)); 43 44 return db; 45 } 46 47 /* 48 ** SMDB_FREE_DATABASE -- Unallocates a database structure. 49 ** 50 ** Parameters: 51 ** database -- a SMDB_DATABASE pointer to deallocate. 52 ** 53 ** Returns: 54 ** None 55 */ 56 57 void 58 smdb_free_database(database) 59 SMDB_DATABASE *database; 60 { 61 if (database != NULL) 62 free(database); 63 } 64 65 /* 66 ** SMDB_LOCKFILE -- lock a file using flock or (shudder) fcntl locking 67 ** 68 ** Parameters: 69 ** fd -- the file descriptor of the file. 70 ** type -- type of the lock. Bits can be: 71 ** LOCK_EX -- exclusive lock. 72 ** LOCK_NB -- non-blocking. 73 ** 74 ** Returns: 75 ** true if the lock was acquired. 76 ** false otherwise. 77 */ 78 79 static bool 80 smdb_lockfile(fd, type) 81 int fd; 82 int type; 83 { 84 int i; 85 int save_errno; 86 #if !HASFLOCK 87 int action; 88 struct flock lfd; 89 90 (void) memset(&lfd, '\0', sizeof lfd); 91 if (bitset(LOCK_UN, type)) 92 lfd.l_type = F_UNLCK; 93 else if (bitset(LOCK_EX, type)) 94 lfd.l_type = F_WRLCK; 95 else 96 lfd.l_type = F_RDLCK; 97 98 if (bitset(LOCK_NB, type)) 99 action = F_SETLK; 100 else 101 action = F_SETLKW; 102 103 while ((i = fcntl(fd, action, &lfd)) < 0 && errno == EINTR) 104 continue; 105 if (i >= 0) 106 return true; 107 save_errno = errno; 108 109 /* 110 ** On SunOS, if you are testing using -oQ/tmp/mqueue or 111 ** -oA/tmp/aliases or anything like that, and /tmp is mounted 112 ** as type "tmp" (that is, served from swap space), the 113 ** previous fcntl will fail with "Invalid argument" errors. 114 ** Since this is fairly common during testing, we will assume 115 ** that this indicates that the lock is successfully grabbed. 116 */ 117 118 if (save_errno == EINVAL) 119 return true; 120 121 if (!bitset(LOCK_NB, type) || 122 (save_errno != EACCES && save_errno != EAGAIN)) 123 { 124 # if 0 125 int omode = fcntl(fd, F_GETFL, NULL); 126 int euid = (int) geteuid(); 127 128 syslog(LOG_ERR, "cannot lockf(%s%s, fd=%d, type=%o, omode=%o, euid=%d)", 129 filename, ext, fd, type, omode, euid); 130 # endif /* 0 */ 131 errno = save_errno; 132 return false; 133 } 134 #else /* !HASFLOCK */ 135 136 while ((i = flock(fd, type)) < 0 && errno == EINTR) 137 continue; 138 if (i >= 0) 139 return true; 140 save_errno = errno; 141 142 if (!bitset(LOCK_NB, type) || save_errno != EWOULDBLOCK) 143 { 144 # if 0 145 int omode = fcntl(fd, F_GETFL, NULL); 146 int euid = (int) geteuid(); 147 148 syslog(LOG_ERR, "cannot flock(%s%s, fd=%d, type=%o, omode=%o, euid=%d)", 149 filename, ext, fd, type, omode, euid); 150 # endif /* 0 */ 151 errno = save_errno; 152 return false; 153 } 154 #endif /* !HASFLOCK */ 155 errno = save_errno; 156 return false; 157 } 158 159 /* 160 ** SMDB_OPEN_DATABASE -- Opens a database. 161 ** 162 ** This opens a database. If type is SMDB_DEFAULT it tries to 163 ** use available DB types. If a specific type is given it will 164 ** try to open a database of that type. 165 ** 166 ** Parameters: 167 ** database -- A pointer to a SMDB_DATABASE pointer where the 168 ** opened database will be stored. This should 169 ** be unallocated. 170 ** db_name -- The name of the database to open. Do not include 171 ** the file name extension. 172 ** mode -- The mode to set on the database file or files. 173 ** mode_mask -- Mode bits that must match on an opened database. 174 ** sff -- Flags to safefile. 175 ** type -- The type of database to open. Supported types 176 ** vary depending on what was compiled in. 177 ** user_info -- Information on the user to use for file 178 ** permissions. 179 ** params -- Params specific to the database being opened. 180 ** Only supports some DB hash options right now 181 ** (see smdb_db_open() for details). 182 ** 183 ** Returns: 184 ** SMDBE_OK -- Success. 185 ** Anything else is an error. Look up more info about the 186 ** error in the comments for the specific open() used. 187 */ 188 189 struct type2func_s 190 { 191 const char *t2f_type; 192 smdb_open_func *t2f_open_fun; 193 }; 194 typedef struct type2func_s type2func_t; 195 static type2func_t type2func[] = { 196 { SMDB_TYPE_HASH, smdb_db_open }, 197 { SMDB_TYPE_BTREE, smdb_db_open }, 198 { SMDB_TYPE_NDBM, smdb_ndbm_open}, 199 { SMDB_TYPE_CDB, smdb_cdb_open }, 200 { NULL, NULL } 201 }; 202 203 int 204 smdb_open_database(database, db_name, mode, mode_mask, sff, type, user_info, 205 params) 206 SMDB_DATABASE **database; 207 char *db_name; 208 int mode; 209 int mode_mask; 210 long sff; 211 SMDB_DBTYPE type; 212 SMDB_USER_INFO *user_info; 213 SMDB_DBPARAMS *params; 214 { 215 bool type_was_default; 216 int result, i; 217 const char *smdb_type; 218 smdb_open_func *smdb_open_fun; 219 220 result = SMDBE_UNSUPPORTED_DB_TYPE; 221 type_was_default = SMDB_IS_TYPE_DEFAULT(type); 222 for (i = 0; (smdb_type = type2func[i].t2f_type) != NULL; i++) 223 { 224 if (!type_was_default && strcmp(type, smdb_type) != 0) 225 continue; 226 smdb_open_fun = type2func[i].t2f_open_fun; 227 if (smdb_open_fun == NULL) 228 { 229 if (type_was_default) 230 continue; 231 else 232 return SMDBE_UNSUPPORTED_DB_TYPE; 233 } 234 result = (*smdb_open_fun)(database, db_name, mode, mode_mask, sff, 235 (char *)smdb_type, user_info, params); 236 if (!((result == ENOENT 237 || result == EINVAL 238 #ifdef EFTYPE 239 || result == EFTYPE 240 #endif 241 ) 242 && type_was_default)) 243 goto ret; 244 } 245 return SMDBE_UNKNOWN_DB_TYPE; 246 247 ret: 248 return result; 249 } 250 251 /* 252 ** SMDB_ADD_EXTENSION -- Adds an extension to a file name. 253 ** 254 ** Just adds a . followed by a string to a db_name if there 255 ** is room and the db_name does not already have that extension. 256 ** 257 ** Parameters: 258 ** full_name -- The final file name. 259 ** max_full_name_len -- The max length for full_name. 260 ** db_name -- The name of the db. 261 ** extension -- The extension to add. 262 ** 263 ** Returns: 264 ** SMDBE_OK -- Success. 265 ** Anything else is an error. Look up more info about the 266 ** error in the comments for the specific open() used. 267 */ 268 269 int 270 smdb_add_extension(full_name, max_full_name_len, db_name, extension) 271 char *full_name; 272 int max_full_name_len; 273 char *db_name; 274 char *extension; 275 { 276 int extension_len; 277 int db_name_len; 278 279 if (full_name == NULL || db_name == NULL || extension == NULL) 280 return SMDBE_INVALID_PARAMETER; 281 282 extension_len = strlen(extension); 283 db_name_len = strlen(db_name); 284 285 if (extension_len + db_name_len + 2 > max_full_name_len) 286 return SMDBE_DB_NAME_TOO_LONG; 287 288 if (db_name_len < extension_len + 1 || 289 db_name[db_name_len - extension_len - 1] != '.' || 290 strcmp(&db_name[db_name_len - extension_len], extension) != 0) 291 (void) sm_snprintf(full_name, max_full_name_len, "%s.%s", 292 db_name, extension); 293 else 294 (void) sm_strlcpy(full_name, db_name, max_full_name_len); 295 296 return SMDBE_OK; 297 } 298 /* 299 ** SMDB_LOCK_FILE -- Locks the database file. 300 ** 301 ** Locks the actual database file. 302 ** 303 ** Parameters: 304 ** lock_fd -- The resulting descriptor for the locked file. 305 ** db_name -- The name of the database without extension. 306 ** mode -- The open mode. 307 ** sff -- Flags to safefile. 308 ** extension -- The extension for the file. 309 ** 310 ** Returns: 311 ** SMDBE_OK -- Success, otherwise errno. 312 */ 313 314 int 315 smdb_lock_file(lock_fd, db_name, mode, sff, extension) 316 int *lock_fd; 317 char *db_name; 318 int mode; 319 long sff; 320 char *extension; 321 { 322 int result; 323 char file_name[MAXPATHLEN]; 324 325 result = smdb_add_extension(file_name, sizeof file_name, db_name, 326 extension); 327 if (result != SMDBE_OK) 328 return result; 329 330 *lock_fd = safeopen(file_name, mode & ~O_TRUNC, DBMMODE, sff); 331 if (*lock_fd < 0) 332 return errno; 333 334 return SMDBE_OK; 335 } 336 337 /* 338 ** SMDB_UNLOCK_FILE -- Unlocks a file - via close() 339 ** 340 ** Parameters: 341 ** lock_fd -- The descriptor for the locked file. 342 ** 343 ** Returns: 344 ** SMDBE_OK -- Success, otherwise errno. 345 */ 346 347 int 348 smdb_unlock_file(lock_fd) 349 int lock_fd; 350 { 351 int result; 352 353 result = close(lock_fd); 354 if (result != 0) 355 return errno; 356 357 return SMDBE_OK; 358 } 359 /* 360 ** SMDB_LOCK_MAP -- Locks a database. 361 ** 362 ** Parameters: 363 ** database -- database description. 364 ** type -- type of the lock. Bits can be: 365 ** LOCK_EX -- exclusive lock. 366 ** LOCK_NB -- non-blocking. 367 ** 368 ** Returns: 369 ** SMDBE_OK -- Success, otherwise errno. 370 */ 371 372 int 373 smdb_lock_map(database, type) 374 SMDB_DATABASE *database; 375 int type; 376 { 377 int fd; 378 379 fd = database->smdb_lockfd(database); 380 if (fd < 0) 381 return SMDBE_NOT_FOUND; 382 if (!smdb_lockfile(fd, type)) 383 return SMDBE_LOCK_NOT_GRANTED; 384 return SMDBE_OK; 385 } 386 /* 387 ** SMDB_UNLOCK_MAP -- Unlocks a database 388 ** 389 ** Parameters: 390 ** database -- database description. 391 ** 392 ** Returns: 393 ** SMDBE_OK -- Success, otherwise errno. 394 */ 395 396 int 397 smdb_unlock_map(database) 398 SMDB_DATABASE *database; 399 { 400 int fd; 401 402 fd = database->smdb_lockfd(database); 403 if (fd < 0) 404 return SMDBE_NOT_FOUND; 405 if (!smdb_lockfile(fd, LOCK_UN)) 406 return SMDBE_LOCK_NOT_HELD; 407 return SMDBE_OK; 408 } 409 /* 410 ** SMDB_SETUP_FILE -- Gets db file ready for use. 411 ** 412 ** Makes sure permissions on file are safe and creates it if it 413 ** doesn't exist. 414 ** 415 ** Parameters: 416 ** db_name -- The name of the database without extension. 417 ** extension -- The extension. 418 ** sff -- Flags to safefile. 419 ** mode_mask -- Mode bits that must match. 420 ** user_info -- Information on the user to use for file 421 ** permissions. 422 ** stat_info -- A place to put the stat info for the file. 423 ** Returns: 424 ** SMDBE_OK -- Success, otherwise errno. 425 */ 426 427 int 428 smdb_setup_file(db_name, extension, mode_mask, sff, user_info, stat_info) 429 char *db_name; 430 char *extension; 431 int mode_mask; 432 long sff; 433 SMDB_USER_INFO *user_info; 434 struct stat *stat_info; 435 { 436 int st; 437 int result; 438 char db_file_name[MAXPATHLEN]; 439 440 result = smdb_add_extension(db_file_name, sizeof db_file_name, db_name, 441 extension); 442 if (result != SMDBE_OK) 443 return result; 444 445 st = safefile(db_file_name, user_info->smdbu_id, 446 user_info->smdbu_group_id, user_info->smdbu_name, 447 sff, mode_mask, stat_info); 448 if (st != 0) 449 return st; 450 451 return SMDBE_OK; 452 } 453 /* 454 ** SMDB_FILECHANGED -- Checks to see if a file changed. 455 ** 456 ** Compares the passed in stat_info with a current stat on 457 ** the passed in file descriptor. Check filechanged for 458 ** return values. 459 ** 460 ** Parameters: 461 ** db_name -- The name of the database without extension. 462 ** extension -- The extension. 463 ** db_fd -- A file descriptor for the database file. 464 ** stat_info -- An old stat_info. 465 ** Returns: 466 ** SMDBE_OK -- Success, otherwise errno. 467 */ 468 469 int 470 smdb_filechanged(db_name, extension, db_fd, stat_info) 471 char *db_name; 472 char *extension; 473 int db_fd; 474 struct stat *stat_info; 475 { 476 int result; 477 char db_file_name[MAXPATHLEN]; 478 479 result = smdb_add_extension(db_file_name, sizeof db_file_name, db_name, 480 extension); 481 if (result != SMDBE_OK) 482 return result; 483 return filechanged(db_file_name, db_fd, stat_info); 484 } 485 486 /* 487 ** SMDB_PRINT_AVAILABLE_TYPES -- Prints the names of the available types. 488 ** 489 ** Parameters: 490 ** ext - also show extension? 491 ** 492 ** Returns: 493 ** None 494 */ 495 496 void 497 smdb_print_available_types(ext) 498 bool ext; 499 { 500 # define PEXT1 ((ext) ? ":" : "") 501 # define PEXT2(x) ((ext) ? x : "") 502 503 #if NDBM 504 printf("%s%s%s\n", SMDB_TYPE_NDBM, PEXT1, PEXT2(SMNDB_DIR_FILE_EXTENSION)); 505 #endif 506 #if NEWDB 507 /* # if SMDB1_FILE_EXTENSION == SMDB2_FILE_EXTENSION */ 508 printf("%s%s%s\n", SMDB_TYPE_HASH, PEXT1, PEXT2(SMDB1_FILE_EXTENSION)); 509 printf("%s%s%s\n", SMDB_TYPE_BTREE, PEXT1, PEXT2(SMDB1_FILE_EXTENSION)); 510 #endif 511 #if CDB 512 printf("%s%s%s\n", SMDB_TYPE_CDB, PEXT1, PEXT2(SMCDB_FILE_EXTENSION)); 513 #endif 514 #ifdef SMDB_TYPE_IMPL 515 printf("%s%s%s\n", SMDB_TYPE_IMPL, PEXT1, ""); 516 #endif 517 } 518 519 /* 520 ** SMDB_IS_DB_TYPE -- Does a name match an available DB type? 521 ** 522 ** Parameters: 523 ** type -- The name of the database type. 524 ** 525 ** Returns: 526 ** true iff match 527 */ 528 529 bool 530 smdb_is_db_type(db_type) 531 const char *db_type; 532 { 533 #if NDBM 534 if (strcmp(db_type, SMDB_TYPE_NDBM) == 0) 535 return true; 536 #endif 537 #if NEWDB 538 if (strcmp(db_type, SMDB_TYPE_HASH) == 0) 539 return true; 540 if (strcmp(db_type, SMDB_TYPE_BTREE) == 0) 541 return true; 542 #endif 543 #if CDB 544 if (strcmp(db_type, SMDB_TYPE_CDB) == 0) 545 return true; 546 #endif 547 return false; 548 } 549 550 551 /* 552 ** SMDB_DB_DEFINITION -- Given a database type, return database definition 553 ** 554 ** Reads though a structure making an association with the database 555 ** type and the required cpp define from sendmail/README. 556 ** List size is dynamic and must be NULL terminated. 557 ** 558 ** Parameters: 559 ** type -- The name of the database type. 560 ** 561 ** Returns: 562 ** definition for type, otherwise NULL. 563 */ 564 565 typedef struct 566 { 567 SMDB_DBTYPE type; 568 char *dbdef; 569 } dbtype; 570 571 static dbtype DatabaseDefs[] = 572 { 573 { SMDB_TYPE_HASH, "NEWDB" }, 574 { SMDB_TYPE_BTREE, "NEWDB" }, 575 { SMDB_TYPE_NDBM, "NDBM" }, 576 { SMDB_TYPE_CDB, "CDB" }, 577 { NULL, "OOPS" } 578 }; 579 580 char * 581 smdb_db_definition(type) 582 SMDB_DBTYPE type; 583 { 584 dbtype *ptr = DatabaseDefs; 585 586 while (ptr != NULL && ptr->type != NULL) 587 { 588 if (strcmp(type, ptr->type) == 0) 589 return ptr->dbdef; 590 ptr++; 591 } 592 return NULL; 593 } 594