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
);
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;
182 0 == adjusted for next function
185 __nss_next2 (service_user
**ni
, const char *fct_name
, const char *fct2_name
,
186 void **fctp
, int status
, int all_values
)
190 if (nss_next_action (*ni
, NSS_STATUS_TRYAGAIN
) == NSS_ACTION_RETURN
191 && nss_next_action (*ni
, NSS_STATUS_UNAVAIL
) == NSS_ACTION_RETURN
192 && nss_next_action (*ni
, NSS_STATUS_NOTFOUND
) == NSS_ACTION_RETURN
193 && nss_next_action (*ni
, NSS_STATUS_SUCCESS
) == NSS_ACTION_RETURN
)
198 /* This is really only for debugging. */
199 if (__builtin_expect (NSS_STATUS_TRYAGAIN
> status
200 || status
> NSS_STATUS_RETURN
, 0))
201 __libc_fatal ("illegal status in __nss_next");
203 if (nss_next_action (*ni
, status
) == NSS_ACTION_RETURN
)
207 if ((*ni
)->next
== NULL
)
214 *fctp
= __nss_lookup_function (*ni
, fct_name
);
215 if (*fctp
== NULL
&& fct2_name
!= NULL
)
216 *fctp
= __nss_lookup_function (*ni
, fct2_name
);
219 && nss_next_action (*ni
, NSS_STATUS_UNAVAIL
) == NSS_ACTION_CONTINUE
220 && (*ni
)->next
!= NULL
);
222 return *fctp
!= NULL
? 0 : -1;
224 libc_hidden_def (__nss_next2
)
228 attribute_compat_text_section
229 __nss_next (service_user
**ni
, const char *fct_name
, void **fctp
, int status
,
232 return __nss_next2 (ni
, fct_name
, NULL
, fctp
, status
, all_values
);
237 __nss_configure_lookup (const char *dbname
, const char *service_line
)
239 service_user
*new_db
;
242 for (cnt
= 0; cnt
< ndatabases
; ++cnt
)
244 int cmp
= strcmp (dbname
, databases
[cnt
].name
);
249 __set_errno (EINVAL
);
254 if (cnt
== ndatabases
)
256 __set_errno (EINVAL
);
260 /* Test whether it is really used. */
261 if (databases
[cnt
].dbp
== NULL
)
262 /* Nothing to do, but we could do. */
265 /* Try to generate new data. */
266 new_db
= nss_parse_service_list (service_line
);
269 /* Illegal service specification. */
270 __set_errno (EINVAL
);
274 /* Prevent multiple threads to change the service table. */
275 __libc_lock_lock (lock
);
277 /* Install new rules. */
278 *databases
[cnt
].dbp
= new_db
;
279 __nss_database_custom
[cnt
] = true;
281 __libc_lock_unlock (lock
);
287 /* Comparison function for searching NI->known tree. */
289 known_compare (const void *p1
, const void *p2
)
291 return p1
== p2
? 0 : strcmp (*(const char *const *) p1
,
292 *(const char *const *) p2
);
296 #if !defined DO_STATIC_NSS || defined SHARED
299 nss_load_library (service_user
*ni
)
301 if (ni
->library
== NULL
)
303 /* This service has not yet been used. Fetch the service
304 library for it, creating a new one if need be. If there
305 is no service table from the file, this static variable
306 holds the head of the service_library list made from the
307 default configuration. */
308 static name_database default_table
;
309 ni
->library
= nss_new_service (service_table
?: &default_table
,
311 if (ni
->library
== NULL
)
315 if (ni
->library
->lib_handle
== NULL
)
317 /* Load the shared library. */
318 size_t shlen
= (7 + strlen (ni
->library
->name
) + 3
319 + strlen (__nss_shlib_revision
) + 1);
320 int saved_errno
= errno
;
321 char shlib_name
[shlen
];
323 /* Construct shared object name. */
324 __stpcpy (__stpcpy (__stpcpy (__stpcpy (shlib_name
,
328 __nss_shlib_revision
);
330 ni
->library
->lib_handle
= __libc_dlopen (shlib_name
);
331 if (ni
->library
->lib_handle
== NULL
)
333 /* Failed to load the library. */
334 ni
->library
->lib_handle
= (void *) -1l;
335 __set_errno (saved_errno
);
339 /* Call the init function when nscd is used. */
340 size_t initlen
= (5 + strlen (ni
->library
->name
)
341 + strlen ("_init") + 1);
342 char init_name
[initlen
];
344 /* Construct the init function name. */
345 __stpcpy (__stpcpy (__stpcpy (init_name
,
350 /* Find the optional init function. */
351 void (*ifct
) (void (*) (size_t, struct traced_file
*))
352 = __libc_dlsym (ni
->library
->lib_handle
, init_name
);
355 void (*cb
) (size_t, struct traced_file
*) = nscd_init_cb
;
370 __nss_lookup_function (service_user
*ni
, const char *fct_name
)
372 void **found
, *result
;
374 /* We now modify global data. Protect it. */
375 __libc_lock_lock (lock
);
377 /* Search the tree of functions previously requested. Data in the
378 tree are `known_function' structures, whose first member is a
379 `const char *', the lookup key. The search returns a pointer to
380 the tree node structure; the first member of the is a pointer to
381 our structure (i.e. what will be a `known_function'); since the
382 first member of that is the lookup key string, &FCT_NAME is close
383 enough to a pointer to our structure to use as a lookup key that
384 will be passed to `known_compare' (above). */
386 found
= __tsearch (&fct_name
, &ni
->known
, &known_compare
);
387 if (*found
!= &fct_name
)
389 /* The search found an existing structure in the tree. */
390 result
= ((known_function
*) *found
)->fct_ptr
;
391 PTR_DEMANGLE (result
);
395 /* This name was not known before. Now we have a node in the tree
396 (in the proper sorted position for FCT_NAME) that points to
397 &FCT_NAME instead of any real `known_function' structure.
398 Allocate a new structure and fill it in. */
400 known_function
*known
= malloc (sizeof *known
);
404 /* Oops. We can't instantiate this node properly.
405 Remove it from the tree. */
406 __tdelete (&fct_name
, &ni
->known
, &known_compare
);
411 /* Point the tree node at this new structure. */
413 known
->fct_name
= fct_name
;
415 #if !defined DO_STATIC_NSS || defined SHARED
416 /* Load the appropriate library. */
417 if (nss_load_library (ni
) != 0)
419 /* This only happens when out of memory. */
421 goto remove_from_tree
;
424 if (ni
->library
->lib_handle
== (void *) -1l)
425 /* Library not found => function not found. */
429 /* Get the desired function. */
430 size_t namlen
= (5 + strlen (ni
->library
->name
) + 1
431 + strlen (fct_name
) + 1);
434 /* Construct the function name. */
435 __stpcpy (__stpcpy (__stpcpy (__stpcpy (name
, "_nss_"),
440 /* Look up the symbol. */
441 result
= __libc_dlsym (ni
->library
->lib_handle
, name
);
444 /* We can't get function address dynamically in static linking. */
446 # define DEFINE_ENT(h,nm) \
447 { #h"_get"#nm"ent_r", _nss_##h##_get##nm##ent_r }, \
448 { #h"_end"#nm"ent", _nss_##h##_end##nm##ent }, \
449 { #h"_set"#nm"ent", _nss_##h##_set##nm##ent },
450 # define DEFINE_GET(h,nm) \
451 { #h"_get"#nm"_r", _nss_##h##_get##nm##_r },
452 # define DEFINE_GETBY(h,nm,ky) \
453 { #h"_get"#nm"by"#ky"_r", _nss_##h##_get##nm##by##ky##_r },
454 static struct fct_tbl
{ const char *fname
; void *fp
; } *tp
, tbl
[] =
456 # include "function.def"
459 size_t namlen
= (5 + strlen (ni
->library
->name
) + 1
460 + strlen (fct_name
) + 1);
463 /* Construct the function name. */
464 __stpcpy (__stpcpy (__stpcpy (name
, ni
->library
->name
),
469 for (tp
= &tbl
[0]; tp
->fname
; tp
++)
470 if (strcmp (tp
->fname
, name
) == 0)
478 /* Remember function pointer for later calls. Even if null, we
479 record it so a second try needn't search the library again. */
480 known
->fct_ptr
= result
;
481 PTR_MANGLE (known
->fct_ptr
);
485 /* Remove the lock. */
486 __libc_lock_unlock (lock
);
490 libc_hidden_def (__nss_lookup_function
)
493 static name_database
*
495 nss_parse_file (const char *fname
)
498 name_database
*result
;
499 name_database_entry
*last
;
503 /* Open the configuration file. */
504 fp
= fopen (fname
, "rc");
508 /* No threads use this stream. */
509 __fsetlocking (fp
, FSETLOCKING_BYCALLER
);
511 result
= (name_database
*) malloc (sizeof (name_database
));
518 result
->entry
= NULL
;
519 result
->library
= NULL
;
525 name_database_entry
*this;
528 n
= __getline (&line
, &len
, fp
);
531 if (line
[n
- 1] == '\n')
534 /* Because the file format does not know any form of quoting we
535 can search forward for the next '#' character and if found
536 make it terminating the line. */
537 *__strchrnul (line
, '#') = '\0';
539 /* If the line is blank it is ignored. */
543 /* Each line completely specifies the actions for a database. */
544 this = nss_getline (line
);
550 result
->entry
= this;
555 while (!feof_unlocked (fp
));
557 /* Free the buffer. */
559 /* Close configuration file. */
566 /* Read the source names:
567 `( <source> ( "[" "!"? (<status> "=" <action> )+ "]" )? )*'
569 static service_user
*
571 nss_parse_service_list (const char *line
)
573 service_user
*result
= NULL
, **nextp
= &result
;
577 service_user
*new_service
;
580 while (isspace (line
[0]))
583 /* No source specified. */
586 /* Read <source> identifier. */
588 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '[')
594 new_service
= (service_user
*) malloc (sizeof (service_user
)
595 + (line
- name
+ 1));
596 if (new_service
== NULL
)
599 *((char *) __mempcpy (new_service
->name
, name
, line
- name
)) = '\0';
601 /* Set default actions. */
602 new_service
->actions
[2 + NSS_STATUS_TRYAGAIN
] = NSS_ACTION_CONTINUE
;
603 new_service
->actions
[2 + NSS_STATUS_UNAVAIL
] = NSS_ACTION_CONTINUE
;
604 new_service
->actions
[2 + NSS_STATUS_NOTFOUND
] = NSS_ACTION_CONTINUE
;
605 new_service
->actions
[2 + NSS_STATUS_SUCCESS
] = NSS_ACTION_RETURN
;
606 new_service
->actions
[2 + NSS_STATUS_RETURN
] = NSS_ACTION_RETURN
;
607 new_service
->library
= NULL
;
608 new_service
->known
= NULL
;
609 new_service
->next
= NULL
;
611 while (isspace (line
[0]))
616 /* Read criterions. */
619 while (line
[0] != '\0' && isspace (line
[0]));
624 enum nss_status status
;
625 lookup_actions action
;
627 /* Grok ! before name to mean all statii but that one. */
628 not = line
[0] == '!';
632 /* Read status name. */
634 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '='
638 /* Compare with known statii. */
639 if (line
- name
== 7)
641 if (__strncasecmp (name
, "SUCCESS", 7) == 0)
642 status
= NSS_STATUS_SUCCESS
;
643 else if (__strncasecmp (name
, "UNAVAIL", 7) == 0)
644 status
= NSS_STATUS_UNAVAIL
;
648 else if (line
- name
== 8)
650 if (__strncasecmp (name
, "NOTFOUND", 8) == 0)
651 status
= NSS_STATUS_NOTFOUND
;
652 else if (__strncasecmp (name
, "TRYAGAIN", 8) == 0)
653 status
= NSS_STATUS_TRYAGAIN
;
660 while (isspace (line
[0]))
666 while (isspace (line
[0]));
669 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != '='
673 if (line
- name
== 6 && __strncasecmp (name
, "RETURN", 6) == 0)
674 action
= NSS_ACTION_RETURN
;
675 else if (line
- name
== 8
676 && __strncasecmp (name
, "CONTINUE", 8) == 0)
677 action
= NSS_ACTION_CONTINUE
;
683 /* Save the current action setting for this status,
684 set them all to the given action, and reset this one. */
685 const lookup_actions save
= new_service
->actions
[2 + status
];
686 new_service
->actions
[2 + NSS_STATUS_TRYAGAIN
] = action
;
687 new_service
->actions
[2 + NSS_STATUS_UNAVAIL
] = action
;
688 new_service
->actions
[2 + NSS_STATUS_NOTFOUND
] = action
;
689 new_service
->actions
[2 + NSS_STATUS_SUCCESS
] = action
;
690 new_service
->actions
[2 + status
] = save
;
693 new_service
->actions
[2 + status
] = action
;
695 /* Skip white spaces. */
696 while (isspace (line
[0]))
699 while (line
[0] != ']');
705 *nextp
= new_service
;
706 nextp
= &new_service
->next
;
710 static name_database_entry
*
712 nss_getline (char *line
)
715 name_database_entry
*result
;
718 /* Ignore leading white spaces. ATTENTION: this is different from
719 what is implemented in Solaris. The Solaris man page says a line
720 beginning with a white space character is ignored. We regard
721 this as just another misfeature in Solaris. */
722 while (isspace (line
[0]))
725 /* Recognize `<database> ":"'. */
727 while (line
[0] != '\0' && !isspace (line
[0]) && line
[0] != ':')
729 if (line
[0] == '\0' || name
== line
)
734 len
= strlen (name
) + 1;
736 result
= (name_database_entry
*) malloc (sizeof (name_database_entry
) + len
);
740 /* Save the database name. */
741 memcpy (result
->name
, name
, len
);
743 /* Parse the list of services. */
744 result
->service
= nss_parse_service_list (line
);
751 static service_library
*
753 nss_new_service (name_database
*database
, const char *name
)
755 service_library
**currentp
= &database
->library
;
757 while (*currentp
!= NULL
)
759 if (strcmp ((*currentp
)->name
, name
) == 0)
761 currentp
= &(*currentp
)->next
;
764 /* We have to add the new service. */
765 *currentp
= (service_library
*) malloc (sizeof (service_library
));
766 if (*currentp
== NULL
)
769 (*currentp
)->name
= name
;
770 (*currentp
)->lib_handle
= NULL
;
771 (*currentp
)->next
= NULL
;
778 /* Load all libraries for the service. */
780 nss_load_all_libraries (const char *service
, const char *def
)
782 service_user
*ni
= NULL
;
784 if (__nss_database_lookup (service
, NULL
, def
, &ni
) == 0)
787 nss_load_library (ni
);
793 /* Called by nscd and nscd alone. */
795 __nss_disable_nscd (void (*cb
) (size_t, struct traced_file
*))
803 /* Find all the relevant modules so that the init functions are called. */
804 nss_load_all_libraries ("passwd", "compat [NOTFOUND=return] files");
805 nss_load_all_libraries ("group", "compat [NOTFOUND=return] files");
806 nss_load_all_libraries ("hosts", "dns [!UNAVAIL=return] files");
807 nss_load_all_libraries ("services", NULL
);
809 /* Disable all uses of NSCD. */
810 __nss_not_use_nscd_passwd
= -1;
811 __nss_not_use_nscd_group
= -1;
812 __nss_not_use_nscd_hosts
= -1;
813 __nss_not_use_nscd_services
= -1;
818 /* Free all resources if necessary. */
819 libc_freeres_fn (free_mem
)
821 name_database
*top
= service_table
;
822 name_database_entry
*entry
;
823 service_library
*library
;
826 /* Maybe we have not read the nsswitch.conf file. */
829 /* Don't disturb ongoing other threads (if there are any). */
830 service_table
= NULL
;
833 while (entry
!= NULL
)
835 name_database_entry
*olde
= entry
;
836 service_user
*service
= entry
->service
;
838 while (service
!= NULL
)
840 service_user
*olds
= service
;
842 if (service
->known
!= NULL
)
843 __tdestroy (service
->known
, free
);
845 service
= service
->next
;
853 library
= top
->library
;
854 while (library
!= NULL
)
856 service_library
*oldl
= library
;
858 if (library
->lib_handle
&& library
->lib_handle
!= (void *) -1l)
859 __libc_dlclose (library
->lib_handle
);
861 library
= library
->next
;