1 /* Copyright (C) 1996-1999,2001-2007,2009,2010 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
24 #include <bits/libc-lock.h>
27 #include <stdio_ext.h>
33 #include <netinet/ether.h>
37 #if !defined DO_STATIC_NSS || defined SHARED
38 # include <gnu/lib-names.h>
42 #include "../nscd/nscd_proto.h"
44 /* Prototypes for the local functions. */
45 static name_database *nss_parse_file (const char *fname) internal_function;
46 static name_database_entry *nss_getline (char *line) internal_function;
47 static service_user *nss_parse_service_list (const char *line)
49 static service_library *nss_new_service (name_database *database,
50 const char *name) internal_function;
53 /* Declare external database variables. */
54 #define DEFINE_DATABASE(name) \
55 extern service_user *__nss_##name##_database attribute_hidden; \
56 weak_extern (__nss_##name##_database)
57 #include "databases.def"
58 #undef DEFINE_DATABASE
60 /* Structure to map database name to variable. */
67 #define DEFINE_DATABASE(name) \
68 { #name, &__nss_##name##_database },
69 #include "databases.def"
70 #undef DEFINE_DATABASE
72 #define ndatabases (sizeof (databases) / sizeof (databases[0]))
74 /* Flags whether custom rules for database is set. */
75 bool __nss_database_custom[NSS_DBSIDX_max];
78 __libc_lock_define_initialized (static, lock)
80 #if !defined DO_STATIC_NSS || defined SHARED
81 /* String with revision number of the shared object files. */
82 static const char *const __nss_shlib_revision = LIBNSS_FILES_SO + 15;
85 /* The root of the whole data base. */
86 static name_database *service_table;
89 /* -1 == database not found
90 0 == database entry pointer stored */
92 __nss_database_lookup (const char *database, const char *alternate_name,
93 const char *defconfig, service_user **ni)
95 /* Prevent multiple threads to change the service table. */
96 __libc_lock_lock (lock);
98 /* Reconsider database variable in case some other thread called
99 `__nss_configure_lookup' while we waited for the lock. */
102 __libc_lock_unlock (lock);
106 /* Are we initialized yet? */
107 if (service_table == NULL)
108 /* Read config file. */
109 service_table = nss_parse_file (_PATH_NSSWITCH_CONF);
111 /* Test whether configuration data is available. */
112 if (service_table != NULL)
114 /* Return first `service_user' entry for DATABASE. */
115 name_database_entry *entry;
117 /* XXX Could use some faster mechanism here. But each database is
118 only requested once and so this might not be critical. */
119 for (entry = service_table->entry; entry != NULL; entry = entry->next)
120 if (strcmp (database, entry->name) == 0)
121 *ni = entry->service;
123 if (*ni == NULL && alternate_name != NULL)
124 /* We haven't found an entry so far. Try to find it with the
126 for (entry = service_table->entry; entry != NULL; entry = entry->next)
127 if (strcmp (alternate_name, entry->name) == 0)
128 *ni = entry->service;
131 /* No configuration data is available, either because nsswitch.conf
132 doesn't exist or because it doesn't has a line for this database.
134 DEFCONFIG specifies the default service list for this database,
135 or null to use the most common default. */
137 *ni = nss_parse_service_list (defconfig
138 ?: "nis [NOTFOUND=return] files");
140 __libc_lock_unlock (lock);
144 libc_hidden_def (__nss_database_lookup)
151 __nss_lookup (service_user **ni, const char *fct_name, const char *fct2_name,
154 *fctp = __nss_lookup_function (*ni, fct_name);
155 if (*fctp == NULL && fct2_name != NULL)
156 *fctp = __nss_lookup_function (*ni, fct2_name);
159 && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
160 && (*ni)->next != NULL)
164 *fctp = __nss_lookup_function (*ni, fct_name);
165 if (*fctp == NULL && fct2_name != NULL)
166 *fctp = __nss_lookup_function (*ni, fct2_name);
169 return *fctp != NULL ? 0 : (*ni)->next == NULL ? 1 : -1;
174 0 == adjusted for next function
177 __nss_next2 (service_user **ni, const char *fct_name, const char *fct2_name,
178 void **fctp, int status, int all_values)
182 if (nss_next_action (*ni, NSS_STATUS_TRYAGAIN) == NSS_ACTION_RETURN
183 && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_RETURN
184 && nss_next_action (*ni, NSS_STATUS_NOTFOUND) == NSS_ACTION_RETURN
185 && nss_next_action (*ni, NSS_STATUS_SUCCESS) == NSS_ACTION_RETURN)
190 /* This is really only for debugging. */
191 if (__builtin_expect (NSS_STATUS_TRYAGAIN > status
192 || status > NSS_STATUS_RETURN, 0))
193 __libc_fatal ("illegal status in __nss_next");
195 if (nss_next_action (*ni, status) == NSS_ACTION_RETURN)
199 if ((*ni)->next == NULL)
206 *fctp = __nss_lookup_function (*ni, fct_name);
207 if (*fctp == NULL && fct2_name != NULL)
208 *fctp = __nss_lookup_function (*ni, fct2_name);
211 && nss_next_action (*ni, NSS_STATUS_UNAVAIL) == NSS_ACTION_CONTINUE
212 && (*ni)->next != NULL);
214 return *fctp != NULL ? 0 : -1;
216 libc_hidden_def (__nss_next2)
220 attribute_compat_text_section
221 __nss_next (service_user **ni, const char *fct_name, void **fctp, int status,
224 return __nss_next2 (ni, fct_name, NULL, fctp, status, all_values);
229 __nss_configure_lookup (const char *dbname, const char *service_line)
231 service_user *new_db;
234 for (cnt = 0; cnt < ndatabases; ++cnt)
236 int cmp = strcmp (dbname, databases[cnt].name);
241 __set_errno (EINVAL);
246 if (cnt == ndatabases)
248 __set_errno (EINVAL);
252 /* Test whether it is really used. */
253 if (databases[cnt].dbp == NULL)
254 /* Nothing to do, but we could do. */
257 /* Try to generate new data. */
258 new_db = nss_parse_service_list (service_line);
261 /* Illegal service specification. */
262 __set_errno (EINVAL);
266 /* Prevent multiple threads to change the service table. */
267 __libc_lock_lock (lock);
269 /* Install new rules. */
270 *databases[cnt].dbp = new_db;
271 __nss_database_custom[cnt] = true;
273 __libc_lock_unlock (lock);
279 /* Comparison function for searching NI->known tree. */
281 known_compare (const void *p1, const void *p2)
283 return p1 == p2 ? 0 : strcmp (*(const char *const *) p1,
284 *(const char *const *) p2);
289 __nss_lookup_function (service_user *ni, const char *fct_name)
291 void **found, *result;
293 /* We now modify global data. Protect it. */
294 __libc_lock_lock (lock);
296 /* Search the tree of functions previously requested. Data in the
297 tree are `known_function' structures, whose first member is a
298 `const char *', the lookup key. The search returns a pointer to
299 the tree node structure; the first member of the is a pointer to
300 our structure (i.e. what will be a `known_function'); since the
301 first member of that is the lookup key string, &FCT_NAME is close
302 enough to a pointer to our structure to use as a lookup key that
303 will be passed to `known_compare' (above). */
305 found = __tsearch (&fct_name, &ni->known, &known_compare);
306 if (*found != &fct_name)
308 /* The search found an existing structure in the tree. */
309 result = ((known_function *) *found)->fct_ptr;
310 PTR_DEMANGLE (result);
314 /* This name was not known before. Now we have a node in the tree
315 (in the proper sorted position for FCT_NAME) that points to
316 &FCT_NAME instead of any real `known_function' structure.
317 Allocate a new structure and fill it in. */
319 known_function *known = malloc (sizeof *known);
323 /* Oops. We can't instantiate this node properly.
324 Remove it from the tree. */
325 __tdelete (&fct_name, &ni->known, &known_compare);
330 /* Point the tree node at this new structure. */
332 known->fct_name = fct_name;
334 if (ni->library == NULL)
336 /* This service has not yet been used. Fetch the service
337 library for it, creating a new one if need be. If there
338 is no service table from the file, this static variable
339 holds the head of the service_library list made from the
340 default configuration. */
341 static name_database default_table;
342 ni->library = nss_new_service (service_table ?: &default_table,
344 if (ni->library == NULL)
346 /* This only happens when out of memory. */
348 goto remove_from_tree;
352 #if !defined DO_STATIC_NSS || defined SHARED
353 if (ni->library->lib_handle == NULL)
355 /* Load the shared library. */
356 size_t shlen = (7 + strlen (ni->library->name) + 3
357 + strlen (__nss_shlib_revision) + 1);
358 int saved_errno = errno;
359 char shlib_name[shlen];
361 /* Construct shared object name. */
362 __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name,
366 __nss_shlib_revision);
368 ni->library->lib_handle = __libc_dlopen (shlib_name);
369 if (ni->library->lib_handle == NULL)
371 /* Failed to load the library. */
372 ni->library->lib_handle = (void *) -1l;
373 __set_errno (saved_errno);
377 if (ni->library->lib_handle == (void *) -1l)
378 /* Library not found => function not found. */
382 /* Get the desired function. */
383 size_t namlen = (5 + strlen (ni->library->name) + 1
384 + strlen (fct_name) + 1);
387 /* Construct the function name. */
388 __stpcpy (__stpcpy (__stpcpy (__stpcpy (name, "_nss_"),
393 /* Look up the symbol. */
394 result = __libc_dlsym (ni->library->lib_handle, name);
397 /* We can't get function address dynamically in static linking. */
399 # define DEFINE_ENT(h,nm) \
400 { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r }, \
401 { #h"_end"#nm"ent", _nss_##h##_end##nm##ent }, \
402 { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
403 # define DEFINE_GET(h,nm) \
404 { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
405 # define DEFINE_GETBY(h,nm,ky) \
406 { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
407 static struct fct_tbl { const char *fname; void *fp; } *tp, tbl[] =
409 # include "function.def"
412 size_t namlen = (5 + strlen (ni->library->name) + 1
413 + strlen (fct_name) + 1);
416 /* Construct the function name. */
417 __stpcpy (__stpcpy (__stpcpy (name, ni->library->name),
422 for (tp = &tbl[0]; tp->fname; tp++)
423 if (strcmp (tp->fname, name) == 0)
431 /* Remember function pointer for later calls. Even if null, we
432 record it so a second try needn't search the library again. */
433 known->fct_ptr = result;
434 PTR_MANGLE (known->fct_ptr);
438 /* Remove the lock. */
439 __libc_lock_unlock (lock);
443 libc_hidden_def (__nss_lookup_function)
446 static name_database *
448 nss_parse_file (const char *fname)
451 name_database *result;
452 name_database_entry *last;
456 /* Open the configuration file. */
457 fp = fopen (fname, "rc");
461 /* No threads use this stream. */
462 __fsetlocking (fp, FSETLOCKING_BYCALLER);
464 result = (name_database *) malloc (sizeof (name_database));
468 result->entry = NULL;
469 result->library = NULL;
475 name_database_entry *this;
478 n = __getline (&line, &len, fp);
481 if (line[n - 1] == '\n')
484 /* Because the file format does not know any form of quoting we
485 can search forward for the next '#' character and if found
486 make it terminating the line. */
487 *__strchrnul (line, '#') = '\0';
489 /* If the line is blank it is ignored. */
493 /* Each line completely specifies the actions for a database. */
494 this = nss_getline (line);
500 result->entry = this;
505 while (!feof_unlocked (fp));
507 /* Free the buffer. */
509 /* Close configuration file. */
516 /* Read the source names:
517 `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
519 static service_user *
521 nss_parse_service_list (const char *line)
523 service_user *result = NULL, **nextp = &result;
527 service_user *new_service;
530 while (isspace (line[0]))
533 /* No source specified. */
536 /* Read <source> identifier. */
538 while (line[0] != '\0' && !isspace (line[0]) && line[0] != '[')
544 new_service = (service_user *) malloc (sizeof (service_user)
545 + (line - name + 1));
546 if (new_service == NULL)
549 *((char *) __mempcpy (new_service->name, name, line - name)) = '\0';
551 /* Set default actions. */
552 new_service->actions[2 + NSS_STATUS_TRYAGAIN] = NSS_ACTION_CONTINUE;
553 new_service->actions[2 + NSS_STATUS_UNAVAIL] = NSS_ACTION_CONTINUE;
554 new_service->actions[2 + NSS_STATUS_NOTFOUND] = NSS_ACTION_CONTINUE;
555 new_service->actions[2 + NSS_STATUS_SUCCESS] = NSS_ACTION_RETURN;
556 new_service->actions[2 + NSS_STATUS_RETURN] = NSS_ACTION_RETURN;
557 new_service->library = NULL;
558 new_service->known = NULL;
559 new_service->next = NULL;
561 while (isspace (line[0]))
566 /* Read criterions. */
569 while (line[0] != '\0' && isspace (line[0]));
574 enum nss_status status;
575 lookup_actions action;
577 /* Grok ! before name to mean all statii but that one. */
578 not = line[0] == '!';
582 /* Read status name. */
584 while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
588 /* Compare with known statii. */
589 if (line - name == 7)
591 if (__strncasecmp (name, "SUCCESS", 7) == 0)
592 status = NSS_STATUS_SUCCESS;
593 else if (__strncasecmp (name, "UNAVAIL", 7) == 0)
594 status = NSS_STATUS_UNAVAIL;
598 else if (line - name == 8)
600 if (__strncasecmp (name, "NOTFOUND", 8) == 0)
601 status = NSS_STATUS_NOTFOUND;
602 else if (__strncasecmp (name, "TRYAGAIN", 8) == 0)
603 status = NSS_STATUS_TRYAGAIN;
610 while (isspace (line[0]))
616 while (isspace (line[0]));
619 while (line[0] != '\0' && !isspace (line[0]) && line[0] != '='
623 if (line - name == 6 && __strncasecmp (name, "RETURN", 6) == 0)
624 action = NSS_ACTION_RETURN;
625 else if (line - name == 8
626 && __strncasecmp (name, "CONTINUE", 8) == 0)
627 action = NSS_ACTION_CONTINUE;
633 /* Save the current action setting for this status,
634 set them all to the given action, and reset this one. */
635 const lookup_actions save = new_service->actions[2 + status];
636 new_service->actions[2 + NSS_STATUS_TRYAGAIN] = action;
637 new_service->actions[2 + NSS_STATUS_UNAVAIL] = action;
638 new_service->actions[2 + NSS_STATUS_NOTFOUND] = action;
639 new_service->actions[2 + NSS_STATUS_SUCCESS] = action;
640 new_service->actions[2 + status] = save;
643 new_service->actions[2 + status] = action;
645 /* Skip white spaces. */
646 while (isspace (line[0]))
649 while (line[0] != ']');
655 *nextp = new_service;
656 nextp = &new_service->next;
660 static name_database_entry *
662 nss_getline (char *line)
665 name_database_entry *result;
668 /* Ignore leading white spaces. ATTENTION: this is different from
669 what is implemented in Solaris. The Solaris man page says a line
670 beginning with a white space character is ignored. We regard
671 this as just another misfeature in Solaris. */
672 while (isspace (line[0]))
675 /* Recognize `<database> ":"'. */
677 while (line[0] != '\0' && !isspace (line[0]) && line[0] != ':')
679 if (line[0] == '\0' || name == line)
684 len = strlen (name) + 1;
686 result = (name_database_entry *) malloc (sizeof (name_database_entry) + len);
690 /* Save the database name. */
691 memcpy (result->name, name, len);
693 /* Parse the list of services. */
694 result->service = nss_parse_service_list (line);
701 static service_library *
703 nss_new_service (name_database *database, const char *name)
705 service_library **currentp = &database->library;
707 while (*currentp != NULL)
709 if (strcmp ((*currentp)->name, name) == 0)
711 currentp = &(*currentp)->next;
714 /* We have to add the new service. */
715 *currentp = (service_library *) malloc (sizeof (service_library));
716 if (*currentp == NULL)
719 (*currentp)->name = name;
720 (*currentp)->lib_handle = NULL;
721 (*currentp)->next = NULL;
727 /* Called by nscd and nscd alone. */
729 __nss_disable_nscd (void)
731 /* Disable all uses of NSCD. */
732 __nss_not_use_nscd_passwd = -1;
733 __nss_not_use_nscd_group = -1;
734 __nss_not_use_nscd_hosts = -1;
735 __nss_not_use_nscd_services = -1;
739 /* Free all resources if necessary. */
740 libc_freeres_fn (free_mem)
742 name_database *top = service_table;
743 name_database_entry *entry;
744 service_library *library;
747 /* Maybe we have not read the nsswitch.conf file. */
750 /* Don't disturb ongoing other threads (if there are any). */
751 service_table = NULL;
754 while (entry != NULL)
756 name_database_entry *olde = entry;
757 service_user *service = entry->service;
759 while (service != NULL)
761 service_user *olds = service;
763 if (service->known != NULL)
764 __tdestroy (service->known, free);
766 service = service->next;
774 library = top->library;
775 while (library != NULL)
777 service_library *oldl = library;
779 if (library->lib_handle && library->lib_handle != (void *) -1l)
780 __libc_dlclose (library->lib_handle);
782 library = library->next;