pwcache.c revision 1.24
1 /* $NetBSD: pwcache.c,v 1.24 2003/08/07 16:42:55 agc Exp $ */ 2 3 /*- 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Keith Muller of the University of California, San Diego. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /*- 36 * Copyright (c) 1992 Keith Muller. 37 * 38 * This code is derived from software contributed to Berkeley by 39 * Keith Muller of the University of California, San Diego. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * This product includes software developed by the University of 52 * California, Berkeley and its contributors. 53 * 4. Neither the name of the University nor the names of its contributors 54 * may be used to endorse or promote products derived from this software 55 * without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 67 * SUCH DAMAGE. 68 */ 69 70 /*- 71 * Copyright (c) 2002 The NetBSD Foundation, Inc. 72 * All rights reserved. 73 * 74 * Redistribution and use in source and binary forms, with or without 75 * modification, are permitted provided that the following conditions 76 * are met: 77 * 1. Redistributions of source code must retain the above copyright 78 * notice, this list of conditions and the following disclaimer. 79 * 2. Redistributions in binary form must reproduce the above copyright 80 * notice, this list of conditions and the following disclaimer in the 81 * documentation and/or other materials provided with the distribution. 82 * 3. All advertising materials mentioning features or use of this software 83 * must display the following acknowledgement: 84 * This product includes software developed by the NetBSD 85 * Foundation, Inc. and its contributors. 86 * 4. Neither the name of The NetBSD Foundation nor the names of its 87 * contributors may be used to endorse or promote products derived 88 * from this software without specific prior written permission. 89 * 90 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 91 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 92 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 93 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 94 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 95 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 96 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 97 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 98 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 99 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 100 * POSSIBILITY OF SUCH DAMAGE. 101 */ 102 103 #include <sys/cdefs.h> 104 #if defined(LIBC_SCCS) && !defined(lint) 105 #if 0 106 static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 5/31/93"; 107 #else 108 __RCSID("$NetBSD: pwcache.c,v 1.24 2003/08/07 16:42:55 agc Exp $"); 109 #endif 110 #endif /* LIBC_SCCS and not lint */ 111 112 #include "namespace.h" 113 114 #include <sys/types.h> 115 #include <sys/param.h> 116 117 #include <assert.h> 118 #include <grp.h> 119 #include <pwd.h> 120 #include <stdio.h> 121 #include <stdlib.h> 122 #include <string.h> 123 #include <unistd.h> 124 125 #ifdef __weak_alias 126 __weak_alias(user_from_uid,_user_from_uid) 127 __weak_alias(group_from_gid,_group_from_gid) 128 __weak_alias(pwcache_userdb,_pwcache_userdb) 129 __weak_alias(pwcache_groupdb,_pwcache_groupdb) 130 #endif 131 132 #if !HAVE_PWCACHE_USERDB 133 #include "pwcache.h" 134 135 /* 136 * routines that control user, group, uid and gid caches (for the archive 137 * member print routine). 138 * IMPORTANT: 139 * these routines cache BOTH hits and misses, a major performance improvement 140 */ 141 142 /* 143 * function pointers to various name lookup routines. 144 * these may be changed as necessary. 145 */ 146 static int (*_pwcache_setgroupent)(int) = setgroupent; 147 static void (*_pwcache_endgrent)(void) = endgrent; 148 static struct group * (*_pwcache_getgrnam)(const char *) = getgrnam; 149 static struct group * (*_pwcache_getgrgid)(gid_t) = getgrgid; 150 static int (*_pwcache_setpassent)(int) = setpassent; 151 static void (*_pwcache_endpwent)(void) = endpwent; 152 static struct passwd * (*_pwcache_getpwnam)(const char *) = getpwnam; 153 static struct passwd * (*_pwcache_getpwuid)(uid_t) = getpwuid; 154 155 /* 156 * internal state 157 */ 158 static int pwopn; /* is password file open */ 159 static int gropn; /* is group file open */ 160 static UIDC **uidtb; /* uid to name cache */ 161 static GIDC **gidtb; /* gid to name cache */ 162 static UIDC **usrtb; /* user name to uid cache */ 163 static GIDC **grptb; /* group name to gid cache */ 164 165 static int uidtb_fail; /* uidtb_start() failed ? */ 166 static int gidtb_fail; /* gidtb_start() failed ? */ 167 static int usrtb_fail; /* usrtb_start() failed ? */ 168 static int grptb_fail; /* grptb_start() failed ? */ 169 170 171 static u_int st_hash(const char *, size_t, int); 172 static int uidtb_start(void); 173 static int gidtb_start(void); 174 static int usrtb_start(void); 175 static int grptb_start(void); 176 177 178 static u_int 179 st_hash(const char *name, size_t len, int tabsz) 180 { 181 u_int key = 0; 182 183 _DIAGASSERT(name != NULL); 184 185 while (len--) { 186 key += *name++; 187 key = (key << 8) | (key >> 24); 188 } 189 190 return (key % tabsz); 191 } 192 193 /* 194 * uidtb_start 195 * creates an an empty uidtb 196 * Return: 197 * 0 if ok, -1 otherwise 198 */ 199 static int 200 uidtb_start(void) 201 { 202 203 if (uidtb != NULL) 204 return (0); 205 if (uidtb_fail) 206 return (-1); 207 if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) { 208 ++uidtb_fail; 209 return (-1); 210 } 211 return (0); 212 } 213 214 /* 215 * gidtb_start 216 * creates an an empty gidtb 217 * Return: 218 * 0 if ok, -1 otherwise 219 */ 220 static int 221 gidtb_start(void) 222 { 223 224 if (gidtb != NULL) 225 return (0); 226 if (gidtb_fail) 227 return (-1); 228 if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) { 229 ++gidtb_fail; 230 return (-1); 231 } 232 return (0); 233 } 234 235 /* 236 * usrtb_start 237 * creates an an empty usrtb 238 * Return: 239 * 0 if ok, -1 otherwise 240 */ 241 static int 242 usrtb_start(void) 243 { 244 245 if (usrtb != NULL) 246 return (0); 247 if (usrtb_fail) 248 return (-1); 249 if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) { 250 ++usrtb_fail; 251 return (-1); 252 } 253 return (0); 254 } 255 256 /* 257 * grptb_start 258 * creates an an empty grptb 259 * Return: 260 * 0 if ok, -1 otherwise 261 */ 262 static int 263 grptb_start(void) 264 { 265 266 if (grptb != NULL) 267 return (0); 268 if (grptb_fail) 269 return (-1); 270 if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) { 271 ++grptb_fail; 272 return (-1); 273 } 274 return (0); 275 } 276 277 #if !HAVE_USER_FROM_UID 278 /* 279 * user_from_uid() 280 * caches the name (if any) for the uid. If noname clear, we always 281 * return the the stored name (if valid or invalid match). 282 * We use a simple hash table. 283 * Return 284 * Pointer to stored name (or a empty string) 285 */ 286 287 const char * 288 user_from_uid(uid_t uid, int noname) 289 { 290 struct passwd *pw; 291 UIDC *ptr, **pptr; 292 293 if ((uidtb == NULL) && (uidtb_start() < 0)) 294 return (NULL); 295 296 /* 297 * see if we have this uid cached 298 */ 299 pptr = uidtb + (uid % UID_SZ); 300 ptr = *pptr; 301 302 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) { 303 /* 304 * have an entry for this uid 305 */ 306 if (!noname || (ptr->valid == VALID)) 307 return (ptr->name); 308 return (NULL); 309 } 310 311 /* 312 * No entry for this uid, we will add it 313 */ 314 if (!pwopn) { 315 if (_pwcache_setpassent != NULL) 316 (*_pwcache_setpassent)(1); 317 ++pwopn; 318 } 319 320 if (ptr == NULL) 321 *pptr = ptr = (UIDC *)malloc(sizeof(UIDC)); 322 323 if ((pw = (*_pwcache_getpwuid)(uid)) == NULL) { 324 /* 325 * no match for this uid in the local password file 326 * a string that is the uid in numeric format 327 */ 328 if (ptr == NULL) 329 return (NULL); 330 ptr->uid = uid; 331 (void)snprintf(ptr->name, UNMLEN, "%lu", (long) uid); 332 ptr->valid = INVALID; 333 if (noname) 334 return (NULL); 335 } else { 336 /* 337 * there is an entry for this uid in the password file 338 */ 339 if (ptr == NULL) 340 return (pw->pw_name); 341 ptr->uid = uid; 342 (void)strlcpy(ptr->name, pw->pw_name, UNMLEN); 343 ptr->valid = VALID; 344 } 345 return (ptr->name); 346 } 347 348 /* 349 * group_from_gid() 350 * caches the name (if any) for the gid. If noname clear, we always 351 * return the the stored name (if valid or invalid match). 352 * We use a simple hash table. 353 * Return 354 * Pointer to stored name (or a empty string) 355 */ 356 357 const char * 358 group_from_gid(gid_t gid, int noname) 359 { 360 struct group *gr; 361 GIDC *ptr, **pptr; 362 363 if ((gidtb == NULL) && (gidtb_start() < 0)) 364 return (NULL); 365 366 /* 367 * see if we have this gid cached 368 */ 369 pptr = gidtb + (gid % GID_SZ); 370 ptr = *pptr; 371 372 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) { 373 /* 374 * have an entry for this gid 375 */ 376 if (!noname || (ptr->valid == VALID)) 377 return (ptr->name); 378 return (NULL); 379 } 380 381 /* 382 * No entry for this gid, we will add it 383 */ 384 if (!gropn) { 385 if (_pwcache_setgroupent != NULL) 386 (*_pwcache_setgroupent)(1); 387 ++gropn; 388 } 389 390 if (ptr == NULL) 391 *pptr = ptr = (GIDC *)malloc(sizeof(GIDC)); 392 393 if ((gr = (*_pwcache_getgrgid)(gid)) == NULL) { 394 /* 395 * no match for this gid in the local group file, put in 396 * a string that is the gid in numberic format 397 */ 398 if (ptr == NULL) 399 return (NULL); 400 ptr->gid = gid; 401 (void)snprintf(ptr->name, GNMLEN, "%lu", (long) gid); 402 ptr->valid = INVALID; 403 if (noname) 404 return (NULL); 405 } else { 406 /* 407 * there is an entry for this group in the group file 408 */ 409 if (ptr == NULL) 410 return (gr->gr_name); 411 ptr->gid = gid; 412 (void)strlcpy(ptr->name, gr->gr_name, GNMLEN); 413 ptr->valid = VALID; 414 } 415 return (ptr->name); 416 } 417 #endif /* HAVE_USER_FROM_UID */ 418 419 /* 420 * uid_from_user() 421 * caches the uid for a given user name. We use a simple hash table. 422 * Return 423 * the uid (if any) for a user name, or a -1 if no match can be found 424 */ 425 426 int 427 uid_from_user(const char *name, uid_t *uid) 428 { 429 struct passwd *pw; 430 UIDC *ptr, **pptr; 431 size_t namelen; 432 433 /* 434 * return -1 for mangled names 435 */ 436 if (name == NULL || ((namelen = strlen(name)) == 0)) 437 return (-1); 438 if ((usrtb == NULL) && (usrtb_start() < 0)) 439 return (-1); 440 441 /* 442 * look up in hash table, if found and valid return the uid, 443 * if found and invalid, return a -1 444 */ 445 pptr = usrtb + st_hash(name, namelen, UNM_SZ); 446 ptr = *pptr; 447 448 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) { 449 if (ptr->valid == INVALID) 450 return (-1); 451 *uid = ptr->uid; 452 return (0); 453 } 454 455 if (!pwopn) { 456 if (_pwcache_setpassent != NULL) 457 (*_pwcache_setpassent)(1); 458 ++pwopn; 459 } 460 461 if (ptr == NULL) 462 *pptr = ptr = (UIDC *)malloc(sizeof(UIDC)); 463 464 /* 465 * no match, look it up, if no match store it as an invalid entry, 466 * or store the matching uid 467 */ 468 if (ptr == NULL) { 469 if ((pw = (*_pwcache_getpwnam)(name)) == NULL) 470 return (-1); 471 *uid = pw->pw_uid; 472 return (0); 473 } 474 (void)strlcpy(ptr->name, name, UNMLEN); 475 if ((pw = (*_pwcache_getpwnam)(name)) == NULL) { 476 ptr->valid = INVALID; 477 return (-1); 478 } 479 ptr->valid = VALID; 480 *uid = ptr->uid = pw->pw_uid; 481 return (0); 482 } 483 484 /* 485 * gid_from_group() 486 * caches the gid for a given group name. We use a simple hash table. 487 * Return 488 * the gid (if any) for a group name, or a -1 if no match can be found 489 */ 490 491 int 492 gid_from_group(const char *name, gid_t *gid) 493 { 494 struct group *gr; 495 GIDC *ptr, **pptr; 496 size_t namelen; 497 498 /* 499 * return -1 for mangled names 500 */ 501 if (name == NULL || ((namelen = strlen(name)) == 0)) 502 return (-1); 503 if ((grptb == NULL) && (grptb_start() < 0)) 504 return (-1); 505 506 /* 507 * look up in hash table, if found and valid return the uid, 508 * if found and invalid, return a -1 509 */ 510 pptr = grptb + st_hash(name, namelen, GID_SZ); 511 ptr = *pptr; 512 513 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) { 514 if (ptr->valid == INVALID) 515 return (-1); 516 *gid = ptr->gid; 517 return (0); 518 } 519 520 if (!gropn) { 521 if (_pwcache_setgroupent != NULL) 522 (*_pwcache_setgroupent)(1); 523 ++gropn; 524 } 525 526 if (ptr == NULL) 527 *pptr = ptr = (GIDC *)malloc(sizeof(GIDC)); 528 529 /* 530 * no match, look it up, if no match store it as an invalid entry, 531 * or store the matching gid 532 */ 533 if (ptr == NULL) { 534 if ((gr = (*_pwcache_getgrnam)(name)) == NULL) 535 return (-1); 536 *gid = gr->gr_gid; 537 return (0); 538 } 539 540 (void)strlcpy(ptr->name, name, GNMLEN); 541 if ((gr = (*_pwcache_getgrnam)(name)) == NULL) { 542 ptr->valid = INVALID; 543 return (-1); 544 } 545 ptr->valid = VALID; 546 *gid = ptr->gid = gr->gr_gid; 547 return (0); 548 } 549 550 #define FLUSHTB(arr, len, fail) \ 551 do { \ 552 if (arr != NULL) { \ 553 for (i = 0; i < len; i++) \ 554 if (arr[i] != NULL) \ 555 free(arr[i]); \ 556 arr = NULL; \ 557 } \ 558 fail = 0; \ 559 } while (/* CONSTCOND */0); 560 561 int 562 pwcache_userdb( 563 int (*a_setpassent)(int), 564 void (*a_endpwent)(void), 565 struct passwd * (*a_getpwnam)(const char *), 566 struct passwd * (*a_getpwuid)(uid_t)) 567 { 568 int i; 569 570 /* a_setpassent and a_endpwent may be NULL */ 571 if (a_getpwnam == NULL || a_getpwuid == NULL) 572 return (-1); 573 574 if (_pwcache_endpwent != NULL) 575 (*_pwcache_endpwent)(); 576 FLUSHTB(uidtb, UID_SZ, uidtb_fail); 577 FLUSHTB(usrtb, UNM_SZ, usrtb_fail); 578 pwopn = 0; 579 _pwcache_setpassent = a_setpassent; 580 _pwcache_endpwent = a_endpwent; 581 _pwcache_getpwnam = a_getpwnam; 582 _pwcache_getpwuid = a_getpwuid; 583 584 return (0); 585 } 586 587 int 588 pwcache_groupdb( 589 int (*a_setgroupent)(int), 590 void (*a_endgrent)(void), 591 struct group * (*a_getgrnam)(const char *), 592 struct group * (*a_getgrgid)(gid_t)) 593 { 594 int i; 595 596 /* a_setgroupent and a_endgrent may be NULL */ 597 if (a_getgrnam == NULL || a_getgrgid == NULL) 598 return (-1); 599 600 if (_pwcache_endgrent != NULL) 601 (*_pwcache_endgrent)(); 602 FLUSHTB(gidtb, GID_SZ, gidtb_fail); 603 FLUSHTB(grptb, GNM_SZ, grptb_fail); 604 gropn = 0; 605 _pwcache_setgroupent = a_setgroupent; 606 _pwcache_endgrent = a_endgrent; 607 _pwcache_getgrnam = a_getgrnam; 608 _pwcache_getgrgid = a_getgrgid; 609 610 return (0); 611 } 612 613 614 #ifdef TEST_PWCACHE 615 616 struct passwd * 617 test_getpwnam(const char *name) 618 { 619 static struct passwd foo; 620 621 memset(&foo, 0, sizeof(foo)); 622 if (strcmp(name, "toor") == 0) { 623 foo.pw_uid = 666; 624 return &foo; 625 } 626 return (getpwnam(name)); 627 } 628 629 int 630 main(int argc, char *argv[]) 631 { 632 uid_t u; 633 int r, i; 634 635 printf("pass 1 (default userdb)\n"); 636 for (i = 1; i < argc; i++) { 637 printf("i: %d, pwopn %d usrtb_fail %d usrtb %p\n", 638 i, pwopn, usrtb_fail, usrtb); 639 r = uid_from_user(argv[i], &u); 640 if (r == -1) 641 printf(" uid_from_user %s: failed\n", argv[i]); 642 else 643 printf(" uid_from_user %s: %d\n", argv[i], u); 644 } 645 printf("pass 1 finish: pwopn %d usrtb_fail %d usrtb %p\n", 646 pwopn, usrtb_fail, usrtb); 647 648 puts(""); 649 printf("pass 2 (replacement userdb)\n"); 650 printf("pwcache_userdb returned %d\n", 651 pwcache_userdb(setpassent, test_getpwnam, getpwuid)); 652 printf("pwopn %d usrtb_fail %d usrtb %p\n", pwopn, usrtb_fail, usrtb); 653 654 for (i = 1; i < argc; i++) { 655 printf("i: %d, pwopn %d usrtb_fail %d usrtb %p\n", 656 i, pwopn, usrtb_fail, usrtb); 657 u = -1; 658 r = uid_from_user(argv[i], &u); 659 if (r == -1) 660 printf(" uid_from_user %s: failed\n", argv[i]); 661 else 662 printf(" uid_from_user %s: %d\n", argv[i], u); 663 } 664 printf("pass 2 finish: pwopn %d usrtb_fail %d usrtb %p\n", 665 pwopn, usrtb_fail, usrtb); 666 667 puts(""); 668 printf("pass 3 (null pointers)\n"); 669 printf("pwcache_userdb returned %d\n", 670 pwcache_userdb(NULL, NULL, NULL)); 671 672 return (0); 673 } 674 #endif /* TEST_PWCACHE */ 675 #endif /* !HAVE_PWCACHE_USERDB */ 676
Indexes created Fri Sep 26 20:09:58 GMT 2025