pwcache.c revision 1.29
1 /* $NetBSD: pwcache.c,v 1.29 2004/06/20 22:20:14 jmc Exp $ */ 2 3 /*- 4 * Copyright (c) 1992 Keith Muller. 5 * Copyright (c) 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Keith Muller of the University of California, San Diego. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 /*- 37 * Copyright (c) 2002 The NetBSD Foundation, Inc. 38 * All rights reserved. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 #if HAVE_NBTOOL_CONFIG_H 70 #include "nbtool_config.h" 71 /* 72 * XXX Undefine the renames of these functions so that we don't 73 * XXX rename the versions found in the host's <pwd.h> by mistake! 74 */ 75 #undef group_from_gid 76 #undef user_from_uid 77 #endif 78 79 #include <sys/cdefs.h> 80 #if defined(LIBC_SCCS) && !defined(lint) 81 #if 0 82 static char sccsid[] = "@(#)cache.c 8.1 (Berkeley) 5/31/93"; 83 #else 84 __RCSID("$NetBSD: pwcache.c,v 1.29 2004/06/20 22:20:14 jmc Exp $"); 85 #endif 86 #endif /* LIBC_SCCS and not lint */ 87 88 #include "namespace.h" 89 90 #include <sys/types.h> 91 #include <sys/param.h> 92 93 #include <assert.h> 94 #include <grp.h> 95 #include <pwd.h> 96 #include <stdio.h> 97 #include <stdlib.h> 98 #include <string.h> 99 #include <unistd.h> 100 101 #if HAVE_NBTOOL_CONFIG_H 102 /* XXX Now, re-apply the renaming that we undid above. */ 103 #define group_from_gid __nbcompat_group_from_gid 104 #define user_from_uid __nbcompat_user_from_uid 105 #endif 106 107 #ifdef __weak_alias 108 __weak_alias(user_from_uid,_user_from_uid) 109 __weak_alias(group_from_gid,_group_from_gid) 110 __weak_alias(pwcache_userdb,_pwcache_userdb) 111 __weak_alias(pwcache_groupdb,_pwcache_groupdb) 112 #endif 113 114 #if !HAVE_PWCACHE_USERDB || HAVE_NBTOOL_CONFIG_H 115 #include "pwcache.h" 116 117 /* 118 * routines that control user, group, uid and gid caches (for the archive 119 * member print routine). 120 * IMPORTANT: 121 * these routines cache BOTH hits and misses, a major performance improvement 122 */ 123 124 /* 125 * function pointers to various name lookup routines. 126 * these may be changed as necessary. 127 */ 128 static int (*_pwcache_setgroupent)(int) = setgroupent; 129 static void (*_pwcache_endgrent)(void) = endgrent; 130 static struct group * (*_pwcache_getgrnam)(const char *) = getgrnam; 131 static struct group * (*_pwcache_getgrgid)(gid_t) = getgrgid; 132 static int (*_pwcache_setpassent)(int) = setpassent; 133 static void (*_pwcache_endpwent)(void) = endpwent; 134 static struct passwd * (*_pwcache_getpwnam)(const char *) = getpwnam; 135 static struct passwd * (*_pwcache_getpwuid)(uid_t) = getpwuid; 136 137 /* 138 * internal state 139 */ 140 static int pwopn; /* is password file open */ 141 static int gropn; /* is group file open */ 142 static UIDC **uidtb; /* uid to name cache */ 143 static GIDC **gidtb; /* gid to name cache */ 144 static UIDC **usrtb; /* user name to uid cache */ 145 static GIDC **grptb; /* group name to gid cache */ 146 147 static int uidtb_fail; /* uidtb_start() failed ? */ 148 static int gidtb_fail; /* gidtb_start() failed ? */ 149 static int usrtb_fail; /* usrtb_start() failed ? */ 150 static int grptb_fail; /* grptb_start() failed ? */ 151 152 153 static u_int st_hash(const char *, size_t, int); 154 static int uidtb_start(void); 155 static int gidtb_start(void); 156 static int usrtb_start(void); 157 static int grptb_start(void); 158 159 160 static u_int 161 st_hash(const char *name, size_t len, int tabsz) 162 { 163 u_int key = 0; 164 165 _DIAGASSERT(name != NULL); 166 167 while (len--) { 168 key += *name++; 169 key = (key << 8) | (key >> 24); 170 } 171 172 return (key % tabsz); 173 } 174 175 /* 176 * uidtb_start 177 * creates an an empty uidtb 178 * Return: 179 * 0 if ok, -1 otherwise 180 */ 181 static int 182 uidtb_start(void) 183 { 184 185 if (uidtb != NULL) 186 return (0); 187 if (uidtb_fail) 188 return (-1); 189 if ((uidtb = (UIDC **)calloc(UID_SZ, sizeof(UIDC *))) == NULL) { 190 ++uidtb_fail; 191 return (-1); 192 } 193 return (0); 194 } 195 196 /* 197 * gidtb_start 198 * creates an an empty gidtb 199 * Return: 200 * 0 if ok, -1 otherwise 201 */ 202 static int 203 gidtb_start(void) 204 { 205 206 if (gidtb != NULL) 207 return (0); 208 if (gidtb_fail) 209 return (-1); 210 if ((gidtb = (GIDC **)calloc(GID_SZ, sizeof(GIDC *))) == NULL) { 211 ++gidtb_fail; 212 return (-1); 213 } 214 return (0); 215 } 216 217 /* 218 * usrtb_start 219 * creates an an empty usrtb 220 * Return: 221 * 0 if ok, -1 otherwise 222 */ 223 static int 224 usrtb_start(void) 225 { 226 227 if (usrtb != NULL) 228 return (0); 229 if (usrtb_fail) 230 return (-1); 231 if ((usrtb = (UIDC **)calloc(UNM_SZ, sizeof(UIDC *))) == NULL) { 232 ++usrtb_fail; 233 return (-1); 234 } 235 return (0); 236 } 237 238 /* 239 * grptb_start 240 * creates an an empty grptb 241 * Return: 242 * 0 if ok, -1 otherwise 243 */ 244 static int 245 grptb_start(void) 246 { 247 248 if (grptb != NULL) 249 return (0); 250 if (grptb_fail) 251 return (-1); 252 if ((grptb = (GIDC **)calloc(GNM_SZ, sizeof(GIDC *))) == NULL) { 253 ++grptb_fail; 254 return (-1); 255 } 256 return (0); 257 } 258 259 /* 260 * user_from_uid() 261 * caches the name (if any) for the uid. If noname clear, we always 262 * return the stored name (if valid or invalid match). 263 * We use a simple hash table. 264 * Return 265 * Pointer to stored name (or a empty string) 266 */ 267 const char * 268 user_from_uid(uid_t uid, int noname) 269 { 270 struct passwd *pw; 271 UIDC *ptr, **pptr; 272 273 if ((uidtb == NULL) && (uidtb_start() < 0)) 274 return (NULL); 275 276 /* 277 * see if we have this uid cached 278 */ 279 pptr = uidtb + (uid % UID_SZ); 280 ptr = *pptr; 281 282 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->uid == uid)) { 283 /* 284 * have an entry for this uid 285 */ 286 if (!noname || (ptr->valid == VALID)) 287 return (ptr->name); 288 return (NULL); 289 } 290 291 /* 292 * No entry for this uid, we will add it 293 */ 294 if (!pwopn) { 295 if (_pwcache_setpassent != NULL) 296 (*_pwcache_setpassent)(1); 297 ++pwopn; 298 } 299 300 if (ptr == NULL) 301 *pptr = ptr = (UIDC *)malloc(sizeof(UIDC)); 302 303 if ((pw = (*_pwcache_getpwuid)(uid)) == NULL) { 304 /* 305 * no match for this uid in the local password file 306 * a string that is the uid in numeric format 307 */ 308 if (ptr == NULL) 309 return (NULL); 310 ptr->uid = uid; 311 (void)snprintf(ptr->name, UNMLEN, "%lu", (long) uid); 312 ptr->valid = INVALID; 313 if (noname) 314 return (NULL); 315 } else { 316 /* 317 * there is an entry for this uid in the password file 318 */ 319 if (ptr == NULL) 320 return (pw->pw_name); 321 ptr->uid = uid; 322 (void)strlcpy(ptr->name, pw->pw_name, UNMLEN); 323 ptr->valid = VALID; 324 } 325 return (ptr->name); 326 } 327 328 /* 329 * group_from_gid() 330 * caches the name (if any) for the gid. If noname clear, we always 331 * return the stored name (if valid or invalid match). 332 * We use a simple hash table. 333 * Return 334 * Pointer to stored name (or a empty string) 335 */ 336 const char * 337 group_from_gid(gid_t gid, int noname) 338 { 339 struct group *gr; 340 GIDC *ptr, **pptr; 341 342 if ((gidtb == NULL) && (gidtb_start() < 0)) 343 return (NULL); 344 345 /* 346 * see if we have this gid cached 347 */ 348 pptr = gidtb + (gid % GID_SZ); 349 ptr = *pptr; 350 351 if ((ptr != NULL) && (ptr->valid > 0) && (ptr->gid == gid)) { 352 /* 353 * have an entry for this gid 354 */ 355 if (!noname || (ptr->valid == VALID)) 356 return (ptr->name); 357 return (NULL); 358 } 359 360 /* 361 * No entry for this gid, we will add it 362 */ 363 if (!gropn) { 364 if (_pwcache_setgroupent != NULL) 365 (*_pwcache_setgroupent)(1); 366 ++gropn; 367 } 368 369 if (ptr == NULL) 370 *pptr = ptr = (GIDC *)malloc(sizeof(GIDC)); 371 372 if ((gr = (*_pwcache_getgrgid)(gid)) == NULL) { 373 /* 374 * no match for this gid in the local group file, put in 375 * a string that is the gid in numberic format 376 */ 377 if (ptr == NULL) 378 return (NULL); 379 ptr->gid = gid; 380 (void)snprintf(ptr->name, GNMLEN, "%lu", (long) gid); 381 ptr->valid = INVALID; 382 if (noname) 383 return (NULL); 384 } else { 385 /* 386 * there is an entry for this group in the group file 387 */ 388 if (ptr == NULL) 389 return (gr->gr_name); 390 ptr->gid = gid; 391 (void)strlcpy(ptr->name, gr->gr_name, GNMLEN); 392 ptr->valid = VALID; 393 } 394 return (ptr->name); 395 } 396 397 /* 398 * uid_from_user() 399 * caches the uid for a given user name. We use a simple hash table. 400 * Return 401 * the uid (if any) for a user name, or a -1 if no match can be found 402 */ 403 int 404 uid_from_user(const char *name, uid_t *uid) 405 { 406 struct passwd *pw; 407 UIDC *ptr, **pptr; 408 size_t namelen; 409 410 /* 411 * return -1 for mangled names 412 */ 413 if (name == NULL || ((namelen = strlen(name)) == 0)) 414 return (-1); 415 if ((usrtb == NULL) && (usrtb_start() < 0)) 416 return (-1); 417 418 /* 419 * look up in hash table, if found and valid return the uid, 420 * if found and invalid, return a -1 421 */ 422 pptr = usrtb + st_hash(name, namelen, UNM_SZ); 423 ptr = *pptr; 424 425 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) { 426 if (ptr->valid == INVALID) 427 return (-1); 428 *uid = ptr->uid; 429 return (0); 430 } 431 432 if (!pwopn) { 433 if (_pwcache_setpassent != NULL) 434 (*_pwcache_setpassent)(1); 435 ++pwopn; 436 } 437 438 if (ptr == NULL) 439 *pptr = ptr = (UIDC *)malloc(sizeof(UIDC)); 440 441 /* 442 * no match, look it up, if no match store it as an invalid entry, 443 * or store the matching uid 444 */ 445 if (ptr == NULL) { 446 if ((pw = (*_pwcache_getpwnam)(name)) == NULL) 447 return (-1); 448 *uid = pw->pw_uid; 449 return (0); 450 } 451 (void)strlcpy(ptr->name, name, UNMLEN); 452 if ((pw = (*_pwcache_getpwnam)(name)) == NULL) { 453 ptr->valid = INVALID; 454 return (-1); 455 } 456 ptr->valid = VALID; 457 *uid = ptr->uid = pw->pw_uid; 458 return (0); 459 } 460 461 /* 462 * gid_from_group() 463 * caches the gid for a given group name. We use a simple hash table. 464 * Return 465 * the gid (if any) for a group name, or a -1 if no match can be found 466 */ 467 int 468 gid_from_group(const char *name, gid_t *gid) 469 { 470 struct group *gr; 471 GIDC *ptr, **pptr; 472 size_t namelen; 473 474 /* 475 * return -1 for mangled names 476 */ 477 if (name == NULL || ((namelen = strlen(name)) == 0)) 478 return (-1); 479 if ((grptb == NULL) && (grptb_start() < 0)) 480 return (-1); 481 482 /* 483 * look up in hash table, if found and valid return the uid, 484 * if found and invalid, return a -1 485 */ 486 pptr = grptb + st_hash(name, namelen, GID_SZ); 487 ptr = *pptr; 488 489 if ((ptr != NULL) && (ptr->valid > 0) && !strcmp(name, ptr->name)) { 490 if (ptr->valid == INVALID) 491 return (-1); 492 *gid = ptr->gid; 493 return (0); 494 } 495 496 if (!gropn) { 497 if (_pwcache_setgroupent != NULL) 498 (*_pwcache_setgroupent)(1); 499 ++gropn; 500 } 501 502 if (ptr == NULL) 503 *pptr = ptr = (GIDC *)malloc(sizeof(GIDC)); 504 505 /* 506 * no match, look it up, if no match store it as an invalid entry, 507 * or store the matching gid 508 */ 509 if (ptr == NULL) { 510 if ((gr = (*_pwcache_getgrnam)(name)) == NULL) 511 return (-1); 512 *gid = gr->gr_gid; 513 return (0); 514 } 515 516 (void)strlcpy(ptr->name, name, GNMLEN); 517 if ((gr = (*_pwcache_getgrnam)(name)) == NULL) { 518 ptr->valid = INVALID; 519 return (-1); 520 } 521 ptr->valid = VALID; 522 *gid = ptr->gid = gr->gr_gid; 523 return (0); 524 } 525 526 #define FLUSHTB(arr, len, fail) \ 527 do { \ 528 if (arr != NULL) { \ 529 for (i = 0; i < len; i++) \ 530 if (arr[i] != NULL) \ 531 free(arr[i]); \ 532 arr = NULL; \ 533 } \ 534 fail = 0; \ 535 } while (/* CONSTCOND */0); 536 537 int 538 pwcache_userdb( 539 int (*a_setpassent)(int), 540 void (*a_endpwent)(void), 541 struct passwd * (*a_getpwnam)(const char *), 542 struct passwd * (*a_getpwuid)(uid_t)) 543 { 544 int i; 545 546 /* a_setpassent and a_endpwent may be NULL */ 547 if (a_getpwnam == NULL || a_getpwuid == NULL) 548 return (-1); 549 550 if (_pwcache_endpwent != NULL) 551 (*_pwcache_endpwent)(); 552 FLUSHTB(uidtb, UID_SZ, uidtb_fail); 553 FLUSHTB(usrtb, UNM_SZ, usrtb_fail); 554 pwopn = 0; 555 _pwcache_setpassent = a_setpassent; 556 _pwcache_endpwent = a_endpwent; 557 _pwcache_getpwnam = a_getpwnam; 558 _pwcache_getpwuid = a_getpwuid; 559 560 return (0); 561 } 562 563 int 564 pwcache_groupdb( 565 int (*a_setgroupent)(int), 566 void (*a_endgrent)(void), 567 struct group * (*a_getgrnam)(const char *), 568 struct group * (*a_getgrgid)(gid_t)) 569 { 570 int i; 571 572 /* a_setgroupent and a_endgrent may be NULL */ 573 if (a_getgrnam == NULL || a_getgrgid == NULL) 574 return (-1); 575 576 if (_pwcache_endgrent != NULL) 577 (*_pwcache_endgrent)(); 578 FLUSHTB(gidtb, GID_SZ, gidtb_fail); 579 FLUSHTB(grptb, GNM_SZ, grptb_fail); 580 gropn = 0; 581 _pwcache_setgroupent = a_setgroupent; 582 _pwcache_endgrent = a_endgrent; 583 _pwcache_getgrnam = a_getgrnam; 584 _pwcache_getgrgid = a_getgrgid; 585 586 return (0); 587 } 588 589 590 #ifdef TEST_PWCACHE 591 592 struct passwd * 593 test_getpwnam(const char *name) 594 { 595 static struct passwd foo; 596 597 memset(&foo, 0, sizeof(foo)); 598 if (strcmp(name, "toor") == 0) { 599 foo.pw_uid = 666; 600 return &foo; 601 } 602 return (getpwnam(name)); 603 } 604 605 int 606 main(int argc, char *argv[]) 607 { 608 uid_t u; 609 int r, i; 610 611 printf("pass 1 (default userdb)\n"); 612 for (i = 1; i < argc; i++) { 613 printf("i: %d, pwopn %d usrtb_fail %d usrtb %p\n", 614 i, pwopn, usrtb_fail, usrtb); 615 r = uid_from_user(argv[i], &u); 616 if (r == -1) 617 printf(" uid_from_user %s: failed\n", argv[i]); 618 else 619 printf(" uid_from_user %s: %d\n", argv[i], u); 620 } 621 printf("pass 1 finish: pwopn %d usrtb_fail %d usrtb %p\n", 622 pwopn, usrtb_fail, usrtb); 623 624 puts(""); 625 printf("pass 2 (replacement userdb)\n"); 626 printf("pwcache_userdb returned %d\n", 627 pwcache_userdb(setpassent, test_getpwnam, getpwuid)); 628 printf("pwopn %d usrtb_fail %d usrtb %p\n", pwopn, usrtb_fail, usrtb); 629 630 for (i = 1; i < argc; i++) { 631 printf("i: %d, pwopn %d usrtb_fail %d usrtb %p\n", 632 i, pwopn, usrtb_fail, usrtb); 633 u = -1; 634 r = uid_from_user(argv[i], &u); 635 if (r == -1) 636 printf(" uid_from_user %s: failed\n", argv[i]); 637 else 638 printf(" uid_from_user %s: %d\n", argv[i], u); 639 } 640 printf("pass 2 finish: pwopn %d usrtb_fail %d usrtb %p\n", 641 pwopn, usrtb_fail, usrtb); 642 643 puts(""); 644 printf("pass 3 (null pointers)\n"); 645 printf("pwcache_userdb returned %d\n", 646 pwcache_userdb(NULL, NULL, NULL)); 647 648 return (0); 649 } 650 #endif /* TEST_PWCACHE */ 651 #endif /* !HAVE_PWCACHE_USERDB */ 652
Indexes created Fri Sep 26 08:10:20 GMT 2025