smdb.c revision 363466
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> 11SM_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 21static 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 34SMDB_DATABASE * 35smdb_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 57void 58smdb_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 79static bool 80smdb_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 189struct type2func_s 190{ 191 const char *t2f_type; 192 smdb_open_func *t2f_open_fun; 193}; 194typedef struct type2func_s type2func_t; 195static 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 203int 204smdb_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 269int 270smdb_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 314int 315smdb_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** SMDB_UNLOCK_FILE -- Unlocks a file 338** 339** Unlocks a file. 340** 341** Parameters: 342** lock_fd -- The descriptor for the locked file. 343** 344** Returns: 345** SMDBE_OK -- Success, otherwise errno. 346*/ 347 348int 349smdb_unlock_file(lock_fd) 350 int lock_fd; 351{ 352 int result; 353 354 result = close(lock_fd); 355 if (result != 0) 356 return errno; 357 358 return SMDBE_OK; 359} 360/* 361** SMDB_LOCK_MAP -- Locks a database. 362** 363** Parameters: 364** database -- database description. 365** type -- type of the lock. Bits can be: 366** LOCK_EX -- exclusive lock. 367** LOCK_NB -- non-blocking. 368** 369** Returns: 370** SMDBE_OK -- Success, otherwise errno. 371*/ 372 373int 374smdb_lock_map(database, type) 375 SMDB_DATABASE *database; 376 int type; 377{ 378 int fd; 379 380 fd = database->smdb_lockfd(database); 381 if (fd < 0) 382 return SMDBE_NOT_FOUND; 383 if (!smdb_lockfile(fd, type)) 384 return SMDBE_LOCK_NOT_GRANTED; 385 return SMDBE_OK; 386} 387/* 388** SMDB_UNLOCK_MAP -- Unlocks a database 389** 390** Parameters: 391** database -- database description. 392** 393** Returns: 394** SMDBE_OK -- Success, otherwise errno. 395*/ 396 397int 398smdb_unlock_map(database) 399 SMDB_DATABASE *database; 400{ 401 int fd; 402 403 fd = database->smdb_lockfd(database); 404 if (fd < 0) 405 return SMDBE_NOT_FOUND; 406 if (!smdb_lockfile(fd, LOCK_UN)) 407 return SMDBE_LOCK_NOT_HELD; 408 return SMDBE_OK; 409} 410/* 411** SMDB_SETUP_FILE -- Gets db file ready for use. 412** 413** Makes sure permissions on file are safe and creates it if it 414** doesn't exist. 415** 416** Parameters: 417** db_name -- The name of the database without extension. 418** extension -- The extension. 419** sff -- Flags to safefile. 420** mode_mask -- Mode bits that must match. 421** user_info -- Information on the user to use for file 422** permissions. 423** stat_info -- A place to put the stat info for the file. 424** Returns: 425** SMDBE_OK -- Success, otherwise errno. 426*/ 427 428int 429smdb_setup_file(db_name, extension, mode_mask, sff, user_info, stat_info) 430 char *db_name; 431 char *extension; 432 int mode_mask; 433 long sff; 434 SMDB_USER_INFO *user_info; 435 struct stat *stat_info; 436{ 437 int st; 438 int result; 439 char db_file_name[MAXPATHLEN]; 440 441 result = smdb_add_extension(db_file_name, sizeof db_file_name, db_name, 442 extension); 443 if (result != SMDBE_OK) 444 return result; 445 446 st = safefile(db_file_name, user_info->smdbu_id, 447 user_info->smdbu_group_id, user_info->smdbu_name, 448 sff, mode_mask, stat_info); 449 if (st != 0) 450 return st; 451 452 return SMDBE_OK; 453} 454/* 455** SMDB_FILECHANGED -- Checks to see if a file changed. 456** 457** Compares the passed in stat_info with a current stat on 458** the passed in file descriptor. Check filechanged for 459** return values. 460** 461** Parameters: 462** db_name -- The name of the database without extension. 463** extension -- The extension. 464** db_fd -- A file descriptor for the database file. 465** stat_info -- An old stat_info. 466** Returns: 467** SMDBE_OK -- Success, otherwise errno. 468*/ 469 470int 471smdb_filechanged(db_name, extension, db_fd, stat_info) 472 char *db_name; 473 char *extension; 474 int db_fd; 475 struct stat *stat_info; 476{ 477 int result; 478 char db_file_name[MAXPATHLEN]; 479 480 result = smdb_add_extension(db_file_name, sizeof db_file_name, db_name, 481 extension); 482 if (result != SMDBE_OK) 483 return result; 484 return filechanged(db_file_name, db_fd, stat_info); 485} 486 487/* 488** SMDB_PRINT_AVAILABLE_TYPES -- Prints the names of the available types. 489** 490** Parameters: 491** None 492** 493** Returns: 494** None 495*/ 496 497void 498smdb_print_available_types(ext) 499 bool ext; 500{ 501# define PEXT1 ((ext) ? ":" : "") 502# define PEXT2(x) ((ext) ? x : "") 503 504#if NDBM 505 printf("%s%s%s\n", SMDB_TYPE_NDBM, PEXT1, PEXT2(SMNDB_DIR_FILE_EXTENSION)); 506#endif 507#if NEWDB 508/* # if SMDB1_FILE_EXTENSION == SMDB2_FILE_EXTENSION */ 509 printf("%s%s%s\n", SMDB_TYPE_HASH, PEXT1, PEXT2(SMDB1_FILE_EXTENSION)); 510 printf("%s%s%s\n", SMDB_TYPE_BTREE, PEXT1, PEXT2(SMDB1_FILE_EXTENSION)); 511#endif 512#if CDB 513 printf("%s%s%s\n", SMDB_TYPE_CDB, PEXT1, PEXT2(SMCDB_FILE_EXTENSION)); 514#endif 515#ifdef SMDB_TYPE_IMPL 516 printf("%s%s%s\n", SMDB_TYPE_IMPL, PEXT1, ""); 517#endif 518} 519 520/* 521** SMDB_IS_DB_TYPE -- Does a name match an available DB type? 522** 523** Parameters: 524** type -- The name of the database type. 525** 526** Returns: 527** true iff match 528*/ 529 530bool 531smdb_is_db_type(db_type) 532 const char *db_type; 533{ 534#if NDBM 535 if (strcmp(db_type, SMDB_TYPE_NDBM) == 0) 536 return true; 537#endif 538#if NEWDB 539 if (strcmp(db_type, SMDB_TYPE_HASH) == 0) 540 return true; 541 if (strcmp(db_type, SMDB_TYPE_BTREE) == 0) 542 return true; 543#endif 544#if CDB 545 if (strcmp(db_type, SMDB_TYPE_CDB) == 0) 546 return true; 547#endif 548 return false; 549} 550 551 552/* 553** SMDB_DB_DEFINITION -- Given a database type, return database definition 554** 555** Reads though a structure making an association with the database 556** type and the required cpp define from sendmail/README. 557** List size is dynamic and must be NULL terminated. 558** 559** Parameters: 560** type -- The name of the database type. 561** 562** Returns: 563** definition for type, otherwise NULL. 564*/ 565 566typedef struct 567{ 568 SMDB_DBTYPE type; 569 char *dbdef; 570} dbtype; 571 572static dbtype DatabaseDefs[] = 573{ 574 { SMDB_TYPE_HASH, "NEWDB" }, 575 { SMDB_TYPE_BTREE, "NEWDB" }, 576 { SMDB_TYPE_NDBM, "NDBM" }, 577 { SMDB_TYPE_CDB, "CDB" }, 578 { NULL, "OOPS" } 579}; 580 581char * 582smdb_db_definition(type) 583 SMDB_DBTYPE type; 584{ 585 dbtype *ptr = DatabaseDefs; 586 587 while (ptr != NULL && ptr->type != NULL) 588 { 589 if (strcmp(type, ptr->type) == 0) 590 return ptr->dbdef; 591 ptr++; 592 } 593 return NULL; 594} 595