1 /* Copyright (C) 1996-1999,2001-2007,2009,2010,2011
2 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25 #include <bits/libc-lock.h>
28 #include <stdio_ext.h>
34 #include <netinet/ether.h>
38 #if !defined DO_STATIC_NSS || defined SHARED
39 # include <gnu/lib-names.h>
43 #include "../nscd/nscd_proto.h"
46 /* Prototypes for the local functions. */
47 static name_database
*nss_parse_file (const char *fname
) internal_function
;
48 static name_database_entry
*nss_getline (char *line
) internal_function
;
49 static service_user
*nss_parse_service_list (const char *line
)
51 static service_library
*nss_new_service (name_database
*database
,
52 const char *name
) internal_function
;
55 /* Declare external database variables. */
56 #define DEFINE_DATABASE(name) \
57 extern service_user *__nss_##name##_database attribute_hidden; \
58 weak_extern (__nss_##name##_database)
59 #include "databases.def"
60 #undef DEFINE_DATABASE
62 /* Structure to map database name to variable. */
69 #define DEFINE_DATABASE(name) \
70 { #name, &__nss_##name##_database },
71 #include "databases.def"
72 #undef DEFINE_DATABASE
74 #define ndatabases (sizeof (databases) / sizeof (databases[0]))
76 /* Flags whether custom rules for database is set. */
77 bool __nss_database_custom
[NSS_DBSIDX_max
];
80 __libc_lock_define_initialized (static, lock
)
82 #if !defined DO_STATIC_NSS || defined SHARED
83 /* String with revision number of the shared object files. */
84 static const char *const __nss_shlib_revision
= LIBNSS_FILES_SO
+ 15;
87 /* The root of the whole data base. */
88 static name_database
*service_table
;
91 /* Nonzero if this is the nscd process. */
93 /* The callback passed to the init functions when nscd is used. */
94 static void (*nscd_init_cb
) (size_t, struct traced_file
*);
97 /* -1 == database not found
98 0 == database entry pointer stored */
100 __nss_database_lookup (const char *database
, const char *alternate_name
,
101 const char *defconfig
, service_user
**ni
)
103 /* Prevent multiple threads to change the service table. */
104 __libc_lock_lock (lock
);
106 /* Reconsider database variable in case some other thread called
107 `__nss_configure_lookup' while we waited for the lock. */
110 __libc_lock_unlock (lock
);
114 /* Are we initialized yet? */
115 if (service_table
== NULL
)
116 /* Read config file. */
117 service_table
= nss_parse_file (_PATH_NSSWITCH_CONF
);
119 /* Test whether configuration data is available. */
120 if (service_table
!= NULL
)
122 /* Return first `service_user' entry for DATABASE. */
123 name_database_entry
*entry
;
125 /* XXX Could use some faster mechanism here. But each database is
126 only requested once and so this might not be critical. */
127 for (entry
= service_table
->entry
; entry
!= NULL
; entry
= entry
->next
)
128 if (strcmp (database
, entry
->name
) == 0)
129 *ni
= entry
->service
;
131 if (*ni
== NULL
&& alternate_name
!= NULL
)
132 /* We haven't found an entry so far. Try to find it with the
134 for (entry
= service_table
->entry
; entry
!= NULL
; entry
= entry
->next
)
135 if (strcmp (alternate_name
, entry
->name
) == 0)
136 *ni
= entry
->service
;
139 /* No configuration data is available, either because nsswitch.conf
140 doesn't exist or because it doesn't have a line for this database.
142 DEFCONFIG specifies the default service list for this database,
143 or null to use the most common default. */
145 *ni
= nss_parse_service_list (defconfig
146 ?: "nis [NOTFOUND=return] files");
148 __libc_lock_unlock (lock
);
150 return *ni
!= NULL
? 0 : -1;
152 libc_hidden_def (__nss_database_lookup
)
159 __nss_lookup (service_user
**ni
, const char *fct_name
, const char *fct2_name
,
162 *fctp
= __nss_lookup_function (*ni
, fct_name
);
163 if (*fctp
== NULL
&& fct2_name
!= NULL
)
164 *fctp
= __nss_lookup_function (*ni
, fct2_name
);
167 && nss_next_action (*ni
, NSS_STATUS_UNAVAIL
) == NSS_ACTION_CONTINUE
168 && (*ni
)->next
!= NULL
)
172 *fctp
= __nss_lookup_function (*ni
, fct_name
);
173 if (*fctp
== NULL
&& fct2_name
!= NULL
)
174 *fctp
= __nss_lookup_function (*ni
, fct2_name
);
177 return *fctp
!= NULL
? 0 : (*ni
)->next
== NULL
? 1 : -1;
179 libc_hidden_def (__nss_lookup
)
183 0 == adjusted for next function
186 __nss_next2 (service_user
**ni
, const char *fct_name
, const char *fct2_name
,
187 void **fctp
, int status
, int all_values
)
191 if (nss_next_action (*ni
, NSS_STATUS_TRYAGAIN
) == NSS_ACTION_RETURN
192 && nss_next_action (*ni
, NSS_STATUS_UNAVAIL
) == NSS_ACTION_RETURN
193 && nss_next_action (*ni
, NSS_STATUS_NOTFOUND
) == NSS_ACTION_RETURN
194 && nss_next_action (*ni
, NSS_STATUS_SUCCESS
) == NSS_ACTION_RETURN
)
199 /* This is really only for debugging. */
200 if (__builtin_expect (NSS_STATUS_TRYAGAIN
> status
201 || status
> NSS_STATUS_RETURN
, 0))
202 __libc_fatal ("illegal status in __nss_next");
204 if (nss_next_action (*ni
, status
) == NSS_ACTION_RETURN
)
208 if ((*ni
)->next
== NULL
)
215 *fctp
= __nss_lookup_function (*ni
, fct_name
);
216 if (*fctp
== NULL
&& fct2_name
!= NULL
)
217 *fctp
= __nss_lookup_function (*ni
, fct2_name
);
220 && nss_next_action (*ni
, NSS_STATUS_UNAVAIL
) == NSS_ACTION_CONTINUE
221 && (*ni
)->next
!= NULL
);
223 return *fctp
!= NULL
? 0 : -1;
225 libc_hidden_def (__nss_next2
)
229 attribute_compat_text_section
230 __nss_next (service_user
**ni
, const char *fct_name
, void **fctp
, int status
,
233 return __nss_next2 (ni
, fct_name
, NULL
, fctp
, status
, all_values
);
238 __nss_configure_lookup (const char *dbname
, const char *service_line
)
240 service_user
*new_db
;
243 for (cnt
= 0; cnt
< ndatabases
; ++cnt
)
245 int cmp
= strcmp (dbname
, databases
[cnt
].name
);
250 __set_errno (EINVAL
);
255 if (cnt
== ndatabases
)
257 __set_errno (EINVAL
);
261 /* Test whether it is really used. */
262 if (databases
[cnt
].dbp
== NULL
)
263 /* Nothing to do, but we could do. */
266 /* Try to generate new data. */
267 new_db
= nss_parse_service_list (service_line
);
270 /* Illegal service specification. */
271 __set_errno (EINVAL
);
275 /* Prevent multiple threads to change the service table. */
276 __libc_lock_lock (lock
);
278 /* Install new rules. */
279 *databases
[cnt
].dbp
= new_db
;
280 __nss_database_custom
[cnt
] = true;
282 __libc_lock_unlock (lock
);
288 /* Comparison function for searching NI->known tree. */
290 known_compare (const void *p1
, const void *p2
)
292 return p1
== p2
? 0 : strcmp (*(const char *const *) p1
,
293 *(const char *const *) p2
);
297 #if !defined DO_STATIC_NSS || defined SHARED
300 nss_load_library (service_user
*ni
)
302 if (ni
->library
== NULL
)
304 /* This service has not yet been used. Fetch the service
305 library for it, creating a new one if need be. If there
306 is no service table from the file, this static variable
307 holds the head of the service_library list made from the
308 default configuration. */
309 static name_database default_table
;
310 ni
->library
= nss_new_service (service_table
?: &default_table
,
312 if (ni
->library
== NULL
)
316 if (ni
->library
->lib_handle
== NULL
)
318 /* Load the shared library. */
319 size_t shlen
= (7 + strlen (ni
->library
->name
) + 3
320 + strlen (__nss_shlib_revision
) + 1);
321 int saved_errno
= errno
;
322 char shlib_name
[shlen
];
324 /* Construct shared object name. */
325 __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name
,
329 __nss_shlib_revision
);
331 ni
->library
->lib_handle
= __libc_dlopen (shlib_name
);
332 if (ni
->library
->lib_handle
== NULL
)
334 /* Failed to load the library. */
335 ni
->library
->lib_handle
= (void *) -1l;
336 __set_errno (saved_errno
);
340 /* Call the init function when nscd is used. */
341 size_t initlen
= (5 + strlen (ni
->library
->name
)
342 + strlen ("_init") + 1);
343 char init_name
[initlen
];
345 /* Construct the init function name. */
346 __stpcpy (__stpcpy (__stpcpy (init_name
,
351 /* Find the optional init function. */
352 void (*ifct
) (void (*) (size_t, struct traced_file
*))
353 = __libc_dlsym (ni
->library
->lib_handle
, init_name
);
356 void (*cb
) (size_t, struct traced_file
*) = nscd_init_cb
;
371 __nss_lookup_function (service_user
*ni
, const char *fct_name
)
373 void **found
, *result
;
375 /* We now modify global data. Protect it. */
376 __libc_lock_lock (lock
);
378 /* Search the tree of functions previously requested. Data in the
379 tree are `known_function' structures, whose first member is a
380 `const char *', the lookup key. The search returns a pointer to
381 the tree node structure; the first member of the is a pointer to
382 our structure (i.e. what will be a `known_function'); since the
383 first member of that is the lookup key string, &FCT_NAME is close
384 enough to a pointer to our structure to use as a lookup key that
385 will be passed to `known_compare' (above). */
387 found
= __tsearch (&fct_name
, &ni
->known
, &known_compare
);
389 /* This means out-of-memory. */
391 else if (*found
!= &fct_name
)
393 /* The search found an existing structure in the tree. */
394 result
= ((known_function
*) *found
)->fct_ptr
;
395 PTR_DEMANGLE (result
);
399 /* This name was not known before. Now we have a node in the tree
400 (in the proper sorted position for FCT_NAME) that points to
401 &FCT_NAME instead of any real `known_function' structure.
402 Allocate a new structure and fill it in. */
404 known_function
*known
= malloc (sizeof *known
);
408 /* Oops. We can't instantiate this node properly.
409 Remove it from the tree. */
410 __tdelete (&fct_name
, &ni
->known
, &known_compare
);
416 /* Point the tree node at this new structure. */
418 known
->fct_name
= fct_name
;
420 #if !defined DO_STATIC_NSS || defined SHARED
421 /* Load the appropriate library. */
422 if (nss_load_library (ni
) != 0)
423 /* This only happens when out of memory. */
424 goto remove_from_tree
;
426 if (ni
->library
->lib_handle
== (void *) -1l)
427 /* Library not found => function not found. */
431 /* Get the desired function. */
432 size_t namlen
= (5 + strlen (ni
->library
->name
) + 1
433 + strlen (fct_name
) + 1);
436 /* Construct the function name. */
437 __stpcpy (__stpcpy (__stpcpy (__stpcpy (name
, "_nss_"),
442 /* Look up the symbol. */
443 result
= __libc_dlsym (ni
->library
->lib_handle
, name
);
446 /* We can't get function address dynamically in static linking. */
448 # define DEFINE_ENT(h,nm) \
449 { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r }, \
450 { #h"_end"#nm"ent", _nss_##h##_end##nm##ent }, \
451 { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
452 # define DEFINE_GET(h,nm) \
453 { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
454 # define DEFINE_GETBY(h,nm,ky) \
455 { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
456 static struct fct_tbl
{ const char *fname
; void *fp
; } *tp
, tbl
[] =
458 # include "function.def"
461 size_t namlen
= (5 + strlen (ni
->library
->name
) + 1
462 + strlen (fct_name
) + 1);
465 /* Construct the function name. */
466 __stpcpy (__stpcpy (__stpcpy (name
, ni
->library
->name
),
471 for (tp
= &tbl
[0]; tp
->fname
; tp
++)
472 if (strcmp (tp
->fname
, name
) == 0)
480 /* Remember function pointer for later calls. Even if null, we
481 record it so a second try needn't search the library again. */
482 known
->fct_ptr
= result
;
483 PTR_MANGLE (known
->fct_ptr
);
487 /* Remove the lock. */
488 __libc_lock_unlock (lock
);
492 libc_hidden_def (__nss_lookup_function
)
495 static name_database
*
497 nss_parse_file (const char *fname
)
500 name_database
*result
;
501 name_database_entry
*last
;
505 /* Open the configuration file. */
506 fp
= fopen (fname
, "rce");
510 /* No threads use this stream. */
511 __fsetlocking (fp
, FSETLOCKING_BYCALLER
);
513 result
= (name_database
*) malloc (sizeof (name_database
));
520 result
->entry
= NULL
;
521 result
->library
= NULL
;
527 name_database_entry
*this;
530 n
= __getline (&line
, &len
, fp
);
533 if (line
[n
- 1] == '\n')
536 /* Because the file format does not know any form of quoting we
537 can search forward for the next '#' character and if found
538 make it terminating the line. */
539 *__strchrnul (line
, '#') = '\0';
541 /* If the line is blank it is ignored. */
545 /* Each line completely specifies the actions for a database. */
546 this = nss_getline (line
);
552 result
->entry
= this;
557 while (!feof_unlocked (fp
));
559 /* Free the buffer. */
561 /* Close configuration file. */
568 /* Read the source names:
569 `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
571 static service_user
*
573 nss_parse_service_list (const char *line
)
575 service_user
*result
= NULL
, **nextp
= &result
;
579 service_user
*new_service
;
582 while (isspace (line
[0]))
585 /* No source specified. */
588 /* Read <source> identifier. */
590 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '[')
596 new_service
= (service_user
*) malloc (sizeof (service_user
)
597 + (line
- name
+ 1));
598 if (new_service
== NULL
)
601 *((char *) __mempcpy (new_service
->name
, name
, line
- name
)) = '\0';
603 /* Set default actions. */
604 new_service
->actions
[2 + NSS_STATUS_TRYAGAIN
] = NSS_ACTION_CONTINUE
;
605 new_service
->actions
[2 + NSS_STATUS_UNAVAIL
] = NSS_ACTION_CONTINUE
;
606 new_service
->actions
[2 + NSS_STATUS_NOTFOUND
] = NSS_ACTION_CONTINUE
;
607 new_service
->actions
[2 + NSS_STATUS_SUCCESS
] = NSS_ACTION_RETURN
;
608 new_service
->actions
[2 + NSS_STATUS_RETURN
] = NSS_ACTION_RETURN
;
609 new_service
->library
= NULL
;
610 new_service
->known
= NULL
;
611 new_service
->next
= NULL
;
613 while (isspace (line
[0]))
618 /* Read criterions. */
621 while (line
[0] != '\0' && isspace (line
[0]));
626 enum nss_status status
;
627 lookup_actions action
;
629 /* Grok ! before name to mean all statii but that one. */
630 not = line
[0] == '!';
634 /* Read status name. */
636 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '='
640 /* Compare with known statii. */
641 if (line
- name
== 7)
643 if (__strncasecmp (name
, "SUCCESS", 7) == 0)
644 status
= NSS_STATUS_SUCCESS
;
645 else if (__strncasecmp (name
, "UNAVAIL", 7) == 0)
646 status
= NSS_STATUS_UNAVAIL
;
650 else if (line
- name
== 8)
652 if (__strncasecmp (name
, "NOTFOUND", 8) == 0)
653 status
= NSS_STATUS_NOTFOUND
;
654 else if (__strncasecmp (name
, "TRYAGAIN", 8) == 0)
655 status
= NSS_STATUS_TRYAGAIN
;
662 while (isspace (line
[0]))
668 while (isspace (line
[0]));
671 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '='
675 if (line
- name
== 6 && __strncasecmp (name
, "RETURN", 6) == 0)
676 action
= NSS_ACTION_RETURN
;
677 else if (line
- name
== 8
678 && __strncasecmp (name
, "CONTINUE", 8) == 0)
679 action
= NSS_ACTION_CONTINUE
;
685 /* Save the current action setting for this status,
686 set them all to the given action, and reset this one. */
687 const lookup_actions save
= new_service
->actions
[2 + status
];
688 new_service
->actions
[2 + NSS_STATUS_TRYAGAIN
] = action
;
689 new_service
->actions
[2 + NSS_STATUS_UNAVAIL
] = action
;
690 new_service
->actions
[2 + NSS_STATUS_NOTFOUND
] = action
;
691 new_service
->actions
[2 + NSS_STATUS_SUCCESS
] = action
;
692 new_service
->actions
[2 + status
] = save
;
695 new_service
->actions
[2 + status
] = action
;
697 /* Skip white spaces. */
698 while (isspace (line
[0]))
701 while (line
[0] != ']');
707 *nextp
= new_service
;
708 nextp
= &new_service
->next
;
712 static name_database_entry
*
714 nss_getline (char *line
)
717 name_database_entry
*result
;
720 /* Ignore leading white spaces. ATTENTION: this is different from
721 what is implemented in Solaris. The Solaris man page says a line
722 beginning with a white space character is ignored. We regard
723 this as just another misfeature in Solaris. */
724 while (isspace (line
[0]))
727 /* Recognize `<database> ":"'. */
729 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != ':')
731 if (line
[0] == '\0' || name
== line
)
736 len
= strlen (name
) + 1;
738 result
= (name_database_entry
*) malloc (sizeof (name_database_entry
) + len
);
742 /* Save the database name. */
743 memcpy (result
->name
, name
, len
);
745 /* Parse the list of services. */
746 result
->service
= nss_parse_service_list (line
);
753 static service_library
*
755 nss_new_service (name_database
*database
, const char *name
)
757 service_library
**currentp
= &database
->library
;
759 while (*currentp
!= NULL
)
761 if (strcmp ((*currentp
)->name
, name
) == 0)
763 currentp
= &(*currentp
)->next
;
766 /* We have to add the new service. */
767 *currentp
= (service_library
*) malloc (sizeof (service_library
));
768 if (*currentp
== NULL
)
771 (*currentp
)->name
= name
;
772 (*currentp
)->lib_handle
= NULL
;
773 (*currentp
)->next
= NULL
;
780 /* Load all libraries for the service. */
782 nss_load_all_libraries (const char *service
, const char *def
)
784 service_user
*ni
= NULL
;
786 if (__nss_database_lookup (service
, NULL
, def
, &ni
) == 0)
789 nss_load_library (ni
);
795 /* Called by nscd and nscd alone. */
797 __nss_disable_nscd (void (*cb
) (size_t, struct traced_file
*))
805 /* Find all the relevant modules so that the init functions are called. */
806 nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
807 nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
808 nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
809 nss_load_all_libraries ("services", NULL
);
811 /* Disable all uses of NSCD. */
812 __nss_not_use_nscd_passwd
= -1;
813 __nss_not_use_nscd_group
= -1;
814 __nss_not_use_nscd_hosts
= -1;
815 __nss_not_use_nscd_services
= -1;
816 __nss_not_use_nscd_netgroup
= -1;
821 /* Free all resources if necessary. */
822 libc_freeres_fn (free_mem
)
824 name_database
*top
= service_table
;
825 name_database_entry
*entry
;
826 service_library
*library
;
829 /* Maybe we have not read the nsswitch.conf file. */
832 /* Don't disturb ongoing other threads (if there are any). */
833 service_table
= NULL
;
836 while (entry
!= NULL
)
838 name_database_entry
*olde
= entry
;
839 service_user
*service
= entry
->service
;
841 while (service
!= NULL
)
843 service_user
*olds
= service
;
845 if (service
->known
!= NULL
)
846 __tdestroy (service
->known
, free
);
848 service
= service
->next
;
856 library
= top
->library
;
857 while (library
!= NULL
)
859 service_library
*oldl
= library
;
861 if (library
->lib_handle
&& library
->lib_handle
!= (void *) -1l)
862 __libc_dlclose (library
->lib_handle
);
864 library
= library
->next
;