1 /* $NetBSD: nsdispatch.c,v 1.9 1999/01/25 00:16:17 lukem Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause 5 * 6 * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Luke Mewburn. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 /*- 34 * Copyright (c) 2003 Networks Associates Technology, Inc. 35 * All rights reserved. 36 * 37 * Portions of this software were developed for the FreeBSD Project by 38 * Jacques A. Vidrine, Safeport Network Services, and Network 39 * Associates Laboratories, the Security Research Division of Network 40 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 41 * ("CBOSS"), as part of the DARPA CHATS research program. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 * 64 */ 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include "namespace.h" 69 #include <sys/param.h> 70 #include <sys/stat.h> 71 72 #include <dlfcn.h> 73 #include <errno.h> 74 #include <fcntl.h> 75 #define _NS_PRIVATE 76 #include <nsswitch.h> 77 #include <pthread.h> 78 #include <pthread_np.h> 79 #include <stdio.h> 80 #include <stdlib.h> 81 #include <string.h> 82 #include <syslog.h> 83 #include <unistd.h> 84 #include "un-namespace.h" 85 #include "nss_tls.h" 86 #include "libc_private.h" 87 #ifdef NS_CACHING 88 #include "nscache.h" 89 #endif 90 91 enum _nss_constants { 92 /* Number of elements allocated when we grow a vector */ 93 ELEMSPERCHUNK = 8 94 }; 95 96 /* 97 * Global NSS data structures are mostly read-only, but we update 98 * them when we read or re-read the nsswitch.conf. 99 */ 100 static pthread_rwlock_t nss_lock = PTHREAD_RWLOCK_INITIALIZER; 101 102 /* 103 * Runtime determination of whether we are dynamically linked or not. 104 */ 105 extern int _DYNAMIC __attribute__ ((weak)); 106 #define is_dynamic() (&_DYNAMIC != NULL) 107 108 /* 109 * default sourcelist: `files' 110 */ 111 const ns_src __nsdefaultsrc[] = { 112 { NSSRC_FILES, NS_SUCCESS }, 113 { 0 }, 114 }; 115 116 /* Database, source mappings. */ 117 static unsigned int _nsmapsize; 118 static ns_dbt *_nsmap = NULL; 119 120 /* NSS modules. */ 121 static unsigned int _nsmodsize; 122 static ns_mod *_nsmod; 123 124 /* Placeholder for builtin modules' dlopen `handle'. */ 125 static int __nss_builtin_handle; 126 static void *nss_builtin_handle = &__nss_builtin_handle; 127 128 #ifdef NS_CACHING 129 /* 130 * Cache lookup cycle prevention function - if !NULL then no cache lookups 131 * will be made 132 */ 133 static void *nss_cache_cycle_prevention_func = NULL; 134 #endif 135 136 /* 137 * We keep track of nsdispatch() nesting depth in dispatch_depth. When a 138 * fallback method is invoked from nsdispatch(), we temporarily set 139 * fallback_depth to the current dispatch depth plus one. Subsequent 140 * calls at that exact depth will run in fallback mode (restricted to the 141 * same source as the call that was handled by the fallback method), while 142 * calls below that depth will be handled normally, allowing fallback 143 * methods to perform arbitrary lookups. 144 */ 145 struct fb_state { 146 int dispatch_depth; 147 int fallback_depth; 148 }; 149 static void fb_endstate(void *); 150 NSS_TLS_HANDLING(fb); 151 152 /* 153 * Attempt to spew relatively uniform messages to syslog. 154 */ 155 #define nss_log(level, fmt, ...) \ 156 syslog((level), "NSSWITCH(%s): " fmt, __func__, __VA_ARGS__) 157 #define nss_log_simple(level, s) \ 158 syslog((level), "NSSWITCH(%s): " s, __func__) 159 160 /* 161 * Dynamically growable arrays are used for lists of databases, sources, 162 * and modules. The following `vector' interface is used to isolate the 163 * common operations. 164 */ 165 typedef int (*vector_comparison)(const void *, const void *); 166 typedef void (*vector_free_elem)(void *); 167 static void vector_sort(void *, unsigned int, size_t, 168 vector_comparison); 169 static void vector_free(void *, unsigned int *, size_t, 170 vector_free_elem); 171 static void *vector_ref(unsigned int, void *, unsigned int, size_t); 172 static void *vector_search(const void *, void *, unsigned int, size_t, 173 vector_comparison); 174 static void *vector_append(const void *, void *, unsigned int *, size_t); 175 176 177 /* 178 * Internal interfaces. 179 */ 180 static int string_compare(const void *, const void *); 181 static int mtab_compare(const void *, const void *); 182 static int nss_configure(void); 183 static void ns_dbt_free(ns_dbt *); 184 static void ns_mod_free(ns_mod *); 185 static void ns_src_free(ns_src **, int); 186 static void nss_load_builtin_modules(void); 187 static void nss_load_module(const char *, nss_module_register_fn); 188 static void nss_atexit(void); 189 /* nsparser */ 190 extern FILE *_nsyyin; 191 192 193 /* 194 * The vector operations 195 */ 196 static void 197 vector_sort(void *vec, unsigned int count, size_t esize, 198 vector_comparison comparison) 199 { 200 qsort(vec, count, esize, comparison); 201 } 202 203 204 static void * 205 vector_search(const void *key, void *vec, unsigned int count, size_t esize, 206 vector_comparison comparison) 207 { 208 return (bsearch(key, vec, count, esize, comparison)); 209 } 210 211 212 static void * 213 vector_append(const void *elem, void *vec, unsigned int *count, size_t esize) 214 { 215 void *p; 216 217 if ((*count % ELEMSPERCHUNK) == 0) { 218 p = reallocarray(vec, *count + ELEMSPERCHUNK, esize); 219 if (p == NULL) { 220 nss_log_simple(LOG_ERR, "memory allocation failure"); 221 return (vec); 222 } 223 vec = p; 224 } 225 memmove((void *)(((uintptr_t)vec) + (*count * esize)), elem, esize); 226 (*count)++; 227 return (vec); 228 } 229 230 231 static void * 232 vector_ref(unsigned int i, void *vec, unsigned int count, size_t esize) 233 { 234 if (i < count) 235 return (void *)((uintptr_t)vec + (i * esize)); 236 else 237 return (NULL); 238 } 239 240 241 #define VECTOR_FREE(v, c, s, f) \ 242 do { vector_free(v, c, s, f); v = NULL; } while (0) 243 static void 244 vector_free(void *vec, unsigned int *count, size_t esize, 245 vector_free_elem free_elem) 246 { 247 unsigned int i; 248 void *elem; 249 250 for (i = 0; i < *count; i++) { 251 elem = vector_ref(i, vec, *count, esize); 252 if (elem != NULL) 253 free_elem(elem); 254 } 255 free(vec); 256 *count = 0; 257 } 258 259 /* 260 * Comparison functions for vector_search. 261 */ 262 static int 263 string_compare(const void *a, const void *b) 264 { 265 return (strcasecmp(*(const char * const *)a, *(const char * const *)b)); 266 } 267 268 269 static int 270 mtab_compare(const void *a, const void *b) 271 { 272 int cmp; 273 274 cmp = strcmp(((const ns_mtab *)a)->name, ((const ns_mtab *)b)->name); 275 if (cmp != 0) 276 return (cmp); 277 else 278 return (strcmp(((const ns_mtab *)a)->database, 279 ((const ns_mtab *)b)->database)); 280 } 281 282 /* 283 * NSS nsmap management. 284 */ 285 void 286 _nsdbtaddsrc(ns_dbt *dbt, const ns_src *src) 287 { 288 const ns_mod *modp; 289 290 dbt->srclist = vector_append(src, dbt->srclist, &dbt->srclistsize, 291 sizeof(*src)); 292 modp = vector_search(&src->name, _nsmod, _nsmodsize, sizeof(*_nsmod), 293 string_compare); 294 if (modp == NULL) 295 nss_load_module(src->name, NULL); 296 } 297 298 299 #ifdef _NSS_DEBUG 300 void 301 _nsdbtdump(const ns_dbt *dbt) 302 { 303 int i; 304 305 printf("%s (%d source%s):", dbt->name, dbt->srclistsize, 306 dbt->srclistsize == 1 ? "" : "s"); 307 for (i = 0; i < (int)dbt->srclistsize; i++) { 308 printf(" %s", dbt->srclist[i].name); 309 if (!(dbt->srclist[i].flags & 310 (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) && 311 (dbt->srclist[i].flags & NS_SUCCESS)) 312 continue; 313 printf(" ["); 314 if (!(dbt->srclist[i].flags & NS_SUCCESS)) 315 printf(" SUCCESS=continue"); 316 if (dbt->srclist[i].flags & NS_UNAVAIL) 317 printf(" UNAVAIL=return"); 318 if (dbt->srclist[i].flags & NS_NOTFOUND) 319 printf(" NOTFOUND=return"); 320 if (dbt->srclist[i].flags & NS_TRYAGAIN) 321 printf(" TRYAGAIN=return"); 322 printf(" ]"); 323 } 324 printf("\n"); 325 } 326 #endif 327 328 329 /* 330 * The first time nsdispatch is called (during a process's lifetime, 331 * or after nsswitch.conf has been updated), nss_configure will 332 * prepare global data needed by NSS. 333 */ 334 static int 335 nss_configure(void) 336 { 337 static time_t confmod; 338 #ifndef NS_REREAD_CONF 339 static int already_initialized = 0; 340 #endif 341 struct stat statbuf; 342 int result, isthreaded; 343 const char *path; 344 #ifdef NS_CACHING 345 void *handle; 346 #endif 347 348 result = 0; 349 isthreaded = __isthreaded; 350 #if defined(_NSS_DEBUG) && defined(_NSS_SHOOT_FOOT) 351 /* NOTE WELL: THIS IS A SECURITY HOLE. This must only be built 352 * for debugging purposes and MUST NEVER be used in production. 353 */ 354 path = getenv("NSSWITCH_CONF"); 355 if (path == NULL) 356 #endif 357 path = _PATH_NS_CONF; 358 #ifndef NS_REREAD_CONF 359 /* 360 * Define NS_REREAD_CONF to have nsswitch notice changes 361 * to nsswitch.conf(5) during runtime. This involves calling 362 * stat(2) every time, which can result in performance hit. 363 */ 364 if (already_initialized) 365 return (0); 366 already_initialized = 1; 367 #endif /* NS_REREAD_CONF */ 368 if (stat(path, &statbuf) != 0) 369 return (0); 370 if (statbuf.st_mtime <= confmod) 371 return (0); 372 if (isthreaded) { 373 (void)_pthread_rwlock_unlock(&nss_lock); 374 result = _pthread_rwlock_wrlock(&nss_lock); 375 if (result != 0) 376 return (result); 377 if (stat(path, &statbuf) != 0) 378 goto fin; 379 if (statbuf.st_mtime <= confmod) 380 goto fin; 381 } 382 _nsyyin = fopen(path, "re"); 383 if (_nsyyin == NULL) 384 goto fin; 385 VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap), 386 (vector_free_elem)ns_dbt_free); 387 VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod), 388 (vector_free_elem)ns_mod_free); 389 if (confmod == 0) 390 (void)atexit(nss_atexit); 391 nss_load_builtin_modules(); 392 _nsyyparse(); 393 (void)fclose(_nsyyin); 394 vector_sort(_nsmap, _nsmapsize, sizeof(*_nsmap), string_compare); 395 confmod = statbuf.st_mtime; 396 397 #ifdef NS_CACHING 398 handle = libc_dlopen(NULL, RTLD_LAZY | RTLD_GLOBAL); 399 if (handle != NULL) { 400 nss_cache_cycle_prevention_func = dlsym(handle, 401 "_nss_cache_cycle_prevention_function"); 402 dlclose(handle); 403 } 404 #endif 405 fin: 406 if (isthreaded) { 407 (void)_pthread_rwlock_unlock(&nss_lock); 408 if (result == 0) 409 result = _pthread_rwlock_rdlock(&nss_lock); 410 } 411 return (result); 412 } 413 414 415 void 416 _nsdbtput(const ns_dbt *dbt) 417 { 418 unsigned int i; 419 ns_dbt *p; 420 421 for (i = 0; i < _nsmapsize; i++) { 422 p = vector_ref(i, _nsmap, _nsmapsize, sizeof(*_nsmap)); 423 if (string_compare(&dbt->name, &p->name) == 0) { 424 /* overwrite existing entry */ 425 if (p->srclist != NULL) 426 ns_src_free(&p->srclist, p->srclistsize); 427 memmove(p, dbt, sizeof(*dbt)); 428 return; 429 } 430 } 431 _nsmap = vector_append(dbt, _nsmap, &_nsmapsize, sizeof(*_nsmap)); 432 } 433 434 435 static void 436 ns_dbt_free(ns_dbt *dbt) 437 { 438 ns_src_free(&dbt->srclist, dbt->srclistsize); 439 if (dbt->name) 440 free((void *)dbt->name); 441 } 442 443 444 static void 445 ns_src_free(ns_src **src, int srclistsize) 446 { 447 int i; 448 449 for (i = 0; i < srclistsize; i++) 450 if ((*src)[i].name != NULL) 451 /* This one was allocated by nslexer. You'll just 452 * have to trust me. 453 */ 454 free((void *)((*src)[i].name)); 455 free(*src); 456 *src = NULL; 457 } 458 459 460 461 /* 462 * NSS module management. 463 */ 464 /* The built-in NSS modules are all loaded at once. */ 465 #define NSS_BACKEND(name, reg) \ 466 ns_mtab *reg(unsigned int *, nss_module_unregister_fn *); 467 #include "nss_backends.h" 468 #undef NSS_BACKEND 469 470 static void 471 nss_load_builtin_modules(void) 472 { 473 #define NSS_BACKEND(name, reg) nss_load_module(#name, reg); 474 #include "nss_backends.h" 475 #undef NSS_BACKEND 476 } 477 478 479 /* Load a built-in or dynamically linked module. If the `reg_fn' 480 * argument is non-NULL, assume a built-in module and use reg_fn to 481 * register it. Otherwise, search for a dynamic NSS module. 482 */ 483 static void 484 nss_load_module(const char *source, nss_module_register_fn reg_fn) 485 { 486 char buf[PATH_MAX]; 487 ns_mod mod; 488 nss_module_register_fn fn; 489 490 memset(&mod, 0, sizeof(mod)); 491 mod.name = strdup(source); 492 if (mod.name == NULL) { 493 nss_log_simple(LOG_ERR, "memory allocation failure"); 494 return; 495 } 496 if (reg_fn != NULL) { 497 /* The placeholder is required, as a NULL handle 498 * represents an invalid module. 499 */ 500 mod.handle = nss_builtin_handle; 501 fn = reg_fn; 502 } else if (!is_dynamic()) { 503 goto fin; 504 } else if (strcmp(source, NSSRC_CACHE) == 0 || 505 strcmp(source, NSSRC_COMPAT) == 0 || 506 strcmp(source, NSSRC_DB) == 0 || 507 strcmp(source, NSSRC_DNS) == 0 || 508 strcmp(source, NSSRC_FILES) == 0 || 509 strcmp(source, NSSRC_NIS) == 0) { 510 /* 511 * Avoid calling dlopen(3) for built-in modules. 512 */ 513 goto fin; 514 } else { 515 if (snprintf(buf, sizeof(buf), "nss_%s.so.%d", mod.name, 516 NSS_MODULE_INTERFACE_VERSION) >= (int)sizeof(buf)) 517 goto fin; 518 mod.handle = libc_dlopen(buf, RTLD_LOCAL|RTLD_LAZY); 519 if (mod.handle == NULL) { 520 #ifdef _NSS_DEBUG 521 /* This gets pretty annoying since the built-in 522 * sources aren't modules yet. 523 */ 524 nss_log(LOG_DEBUG, "%s, %s", mod.name, dlerror()); 525 #endif 526 goto fin; 527 } 528 fn = (nss_module_register_fn)dlfunc(mod.handle, 529 "nss_module_register"); 530 if (fn == NULL) { 531 (void)dlclose(mod.handle); 532 mod.handle = NULL; 533 nss_log(LOG_ERR, "%s, %s", mod.name, dlerror()); 534 goto fin; 535 } 536 } 537 mod.mtab = fn(mod.name, &mod.mtabsize, &mod.unregister); 538 if (mod.mtab == NULL || mod.mtabsize == 0) { 539 if (mod.handle != nss_builtin_handle) 540 (void)dlclose(mod.handle); 541 mod.handle = NULL; 542 nss_log(LOG_ERR, "%s, registration failed", mod.name); 543 goto fin; 544 } 545 if (mod.mtabsize > 1) 546 qsort(mod.mtab, mod.mtabsize, sizeof(mod.mtab[0]), 547 mtab_compare); 548 fin: 549 _nsmod = vector_append(&mod, _nsmod, &_nsmodsize, sizeof(*_nsmod)); 550 vector_sort(_nsmod, _nsmodsize, sizeof(*_nsmod), string_compare); 551 } 552 553 static int exiting = 0; 554 555 static void 556 ns_mod_free(ns_mod *mod) 557 { 558 559 free(mod->name); 560 if (mod->handle == NULL) 561 return; 562 if (mod->unregister != NULL) 563 mod->unregister(mod->mtab, mod->mtabsize); 564 if (mod->handle != nss_builtin_handle && !exiting) 565 (void)dlclose(mod->handle); 566 } 567 568 /* 569 * Cleanup 570 */ 571 static void 572 nss_atexit(void) 573 { 574 int isthreaded; 575 576 exiting = 1; 577 isthreaded = __isthreaded; 578 if (isthreaded) 579 (void)_pthread_rwlock_wrlock(&nss_lock); 580 VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap), 581 (vector_free_elem)ns_dbt_free); 582 VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod), 583 (vector_free_elem)ns_mod_free); 584 if (isthreaded) 585 (void)_pthread_rwlock_unlock(&nss_lock); 586 } 587 588 /* 589 * Finally, the actual implementation. 590 */ 591 static nss_method 592 nss_method_lookup(const char *source, const char *database, 593 const char *method, const ns_dtab disp_tab[], void **mdata) 594 { 595 ns_mod *mod; 596 ns_mtab *match, key; 597 int i; 598 599 if (disp_tab != NULL) 600 for (i = 0; disp_tab[i].src != NULL; i++) 601 if (strcasecmp(source, disp_tab[i].src) == 0) { 602 *mdata = disp_tab[i].mdata; 603 return (disp_tab[i].method); 604 } 605 mod = vector_search(&source, _nsmod, _nsmodsize, sizeof(*_nsmod), 606 string_compare); 607 if (mod != NULL && mod->handle != NULL) { 608 key.database = database; 609 key.name = method; 610 match = bsearch(&key, mod->mtab, mod->mtabsize, 611 sizeof(mod->mtab[0]), mtab_compare); 612 if (match != NULL) { 613 *mdata = match->mdata; 614 return (match->method); 615 } 616 } 617 618 *mdata = NULL; 619 return (NULL); 620 } 621 622 static void 623 fb_endstate(void *p) 624 { 625 free(p); 626 } 627 628 __weak_reference(_nsdispatch, nsdispatch); 629 630 int 631 _nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database, 632 const char *method_name, const ns_src defaults[], ...) 633 { 634 va_list ap; 635 const ns_dbt *dbt; 636 const ns_src *srclist; 637 nss_method method, fb_method; 638 void *mdata; 639 int isthreaded, serrno, i, result, srclistsize; 640 struct fb_state *st; 641 int saved_depth; 642 643 #ifdef NS_CACHING 644 nss_cache_data cache_data; 645 nss_cache_data *cache_data_p; 646 int cache_flag; 647 #endif 648 649 dbt = NULL; 650 fb_method = NULL; 651 652 isthreaded = __isthreaded; 653 serrno = errno; 654 if (isthreaded) { 655 result = _pthread_rwlock_rdlock(&nss_lock); 656 if (result != 0) { 657 result = NS_UNAVAIL; 658 goto fin; 659 } 660 } 661 662 result = fb_getstate(&st); 663 if (result != 0) { 664 result = NS_UNAVAIL; 665 goto fin; 666 } 667 668 result = nss_configure(); 669 if (result != 0) { 670 result = NS_UNAVAIL; 671 goto fin; 672 } 673 ++st->dispatch_depth; 674 if (st->dispatch_depth > st->fallback_depth) { 675 dbt = vector_search(&database, _nsmap, _nsmapsize, sizeof(*_nsmap), 676 string_compare); 677 fb_method = nss_method_lookup(NSSRC_FALLBACK, database, 678 method_name, disp_tab, &mdata); 679 } 680 681 if (dbt != NULL) { 682 srclist = dbt->srclist; 683 srclistsize = dbt->srclistsize; 684 } else { 685 srclist = defaults; 686 srclistsize = 0; 687 while (srclist[srclistsize].name != NULL) 688 srclistsize++; 689 } 690 691 #ifdef NS_CACHING 692 cache_data_p = NULL; 693 cache_flag = 0; 694 #endif 695 for (i = 0; i < srclistsize; i++) { 696 result = NS_NOTFOUND; 697 method = nss_method_lookup(srclist[i].name, database, 698 method_name, disp_tab, &mdata); 699 700 if (method != NULL) { 701 #ifdef NS_CACHING 702 if (strcmp(srclist[i].name, NSSRC_CACHE) == 0 && 703 nss_cache_cycle_prevention_func == NULL) { 704 #ifdef NS_STRICT_LIBC_EID_CHECKING 705 if (issetugid() != 0) 706 continue; 707 #endif 708 cache_flag = 1; 709 710 memset(&cache_data, 0, sizeof(nss_cache_data)); 711 cache_data.info = (nss_cache_info const *)mdata; 712 cache_data_p = &cache_data; 713 714 va_start(ap, defaults); 715 if (cache_data.info->id_func != NULL) 716 result = __nss_common_cache_read(retval, 717 cache_data_p, ap); 718 else if (cache_data.info->marshal_func != NULL) 719 result = __nss_mp_cache_read(retval, 720 cache_data_p, ap); 721 else 722 result = __nss_mp_cache_end(retval, 723 cache_data_p, ap); 724 va_end(ap); 725 } else { 726 cache_flag = 0; 727 errno = 0; 728 va_start(ap, defaults); 729 result = method(retval, mdata, ap); 730 va_end(ap); 731 } 732 #else /* NS_CACHING */ 733 errno = 0; 734 va_start(ap, defaults); 735 result = method(retval, mdata, ap); 736 va_end(ap); 737 #endif /* NS_CACHING */ 738 739 if (result & (srclist[i].flags)) 740 break; 741 } else { 742 if (fb_method != NULL) { 743 saved_depth = st->fallback_depth; 744 st->fallback_depth = st->dispatch_depth + 1; 745 va_start(ap, defaults); 746 result = fb_method(retval, 747 (void *)srclist[i].name, ap); 748 va_end(ap); 749 st->fallback_depth = saved_depth; 750 } else 751 nss_log(LOG_DEBUG, "%s, %s, %s, not found, " 752 "and no fallback provided", 753 srclist[i].name, database, method_name); 754 } 755 } 756 757 #ifdef NS_CACHING 758 if (cache_data_p != NULL && 759 (result & (NS_NOTFOUND | NS_SUCCESS)) && cache_flag == 0) { 760 va_start(ap, defaults); 761 if (result == NS_SUCCESS) { 762 if (cache_data.info->id_func != NULL) 763 __nss_common_cache_write(retval, cache_data_p, 764 ap); 765 else if (cache_data.info->marshal_func != NULL) 766 __nss_mp_cache_write(retval, cache_data_p, ap); 767 } else if (result == NS_NOTFOUND) { 768 if (cache_data.info->id_func == NULL) { 769 if (cache_data.info->marshal_func != NULL) 770 __nss_mp_cache_write_submit(retval, 771 cache_data_p, ap); 772 } else 773 __nss_common_cache_write_negative(cache_data_p); 774 } 775 va_end(ap); 776 } 777 #endif /* NS_CACHING */ 778 779 if (isthreaded) 780 (void)_pthread_rwlock_unlock(&nss_lock); 781 --st->dispatch_depth; 782 fin: 783 errno = serrno; 784 return (result); 785 } 786