1 /* Copyright (C) 1998-2003, 2004 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998.
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
26 #include <stdio_ext.h>
29 #include <rpc/types.h>
30 #include <sys/param.h>
32 #include <bits/libc-lock.h>
34 static service_user
*ni
;
35 /* Type of the lookup function. */
36 static enum nss_status (*nss_initgroups_dyn
) (const char *, gid_t
,
37 long int *, long int *,
38 gid_t
**, long int, int *);
39 static enum nss_status (*nss_setgrent
) (int stayopen
);
40 static enum nss_status (*nss_getgrnam_r
) (const char *name
,
41 struct group
* grp
, char *buffer
,
42 size_t buflen
, int *errnop
);
43 static enum nss_status (*nss_getgrgid_r
) (gid_t gid
, struct group
* grp
,
44 char *buffer
, size_t buflen
,
46 static enum nss_status (*nss_getgrent_r
) (struct group
* grp
, char *buffer
,
47 size_t buflen
, int *errnop
);
48 static enum nss_status (*nss_endgrent
) (void);
50 /* Protect global state against multiple changers. */
51 __libc_lock_define_initialized (static, lock
)
54 /* Get the declaration of the parser function. */
56 #define STRUCTURE group
58 #include <nss/nss_files/files-parse.c>
60 /* Structure for remembering -group members ... */
61 #define BLACKLIST_INITIAL_SIZE 512
62 #define BLACKLIST_INCREMENT 256
74 struct blacklist_t blacklist
;
76 typedef struct ent_t ent_t
;
79 /* Prototypes for local functions. */
80 static void blacklist_store_name (const char *, ent_t
*);
81 static int in_blacklist (const char *, int, ent_t
*);
83 /* Initialize the NSS interface/functions. The calling function must
86 init_nss_interface (void)
88 __libc_lock_lock (lock
);
92 && __nss_database_lookup ("group_compat", NULL
, "nis", &ni
) >= 0)
94 nss_initgroups_dyn
= __nss_lookup_function (ni
, "initgroups_dyn");
95 nss_setgrent
= __nss_lookup_function (ni
, "setgrent");
96 nss_getgrnam_r
= __nss_lookup_function (ni
, "getgrnam_r");
97 nss_getgrgid_r
= __nss_lookup_function (ni
, "getgrgid_r");
98 nss_getgrent_r
= __nss_lookup_function (ni
, "getgrent_r");
99 nss_endgrent
= __nss_lookup_function (ni
, "endgrent");
102 __libc_lock_unlock (lock
);
105 static enum nss_status
106 internal_setgrent (ent_t
*ent
)
108 enum nss_status status
= NSS_STATUS_SUCCESS
;
113 init_nss_interface ();
115 if (ent
->blacklist
.data
!= NULL
)
117 ent
->blacklist
.current
= 1;
118 ent
->blacklist
.data
[0] = '|';
119 ent
->blacklist
.data
[1] = '\0';
122 ent
->blacklist
.current
= 0;
124 ent
->stream
= fopen ("/etc/group", "rm");
126 if (ent
->stream
== NULL
)
127 status
= errno
== EAGAIN
? NSS_STATUS_TRYAGAIN
: NSS_STATUS_UNAVAIL
;
130 /* We have to make sure the file is `closed on exec'. */
133 result
= flags
= fcntl (fileno_unlocked (ent
->stream
), F_GETFD
, 0);
137 result
= fcntl (fileno_unlocked (ent
->stream
), F_SETFD
, flags
);
141 /* Something went wrong. Close the stream and return a
143 fclose (ent
->stream
);
145 status
= NSS_STATUS_UNAVAIL
;
148 /* We take care of locking ourself. */
149 __fsetlocking (ent
->stream
, FSETLOCKING_BYCALLER
);
156 static enum nss_status
157 internal_endgrent (ent_t
*ent
)
159 if (ent
->stream
!= NULL
)
161 fclose (ent
->stream
);
165 if (ent
->blacklist
.data
!= NULL
)
167 ent
->blacklist
.current
= 1;
168 ent
->blacklist
.data
[0] = '|';
169 ent
->blacklist
.data
[1] = '\0';
172 ent
->blacklist
.current
= 0;
174 return NSS_STATUS_SUCCESS
;
177 /* This function checks, if the user is a member of this group and if
178 yes, add the group id to the list. */
180 check_and_add_group (const char *user
, gid_t group
, long int *start
,
181 long int *size
, gid_t
**groupsp
, long int limit
,
184 gid_t
*groups
= *groupsp
;
187 /* Don't add main group to list of groups. */
188 if (grp
->gr_gid
== group
)
191 for (member
= grp
->gr_mem
; *member
!= NULL
; ++member
)
192 if (strcmp (*member
, user
) == 0)
194 /* Matches user. Insert this group. */
197 /* Need a bigger buffer. */
201 if (limit
> 0 && *size
== limit
)
202 /* We reached the maximum. */
208 newsize
= MIN (limit
, 2 * *size
);
210 newgroups
= realloc (groups
, newsize
* sizeof (*groups
));
211 if (newgroups
== NULL
)
213 *groupsp
= groups
= newgroups
;
217 groups
[*start
] = grp
->gr_gid
;
224 /* Get the next group from NSS (+ entry). If the NSS module supports
225 initgroups_dyn, get all entries at once. */
226 static enum nss_status
227 getgrent_next_nss (ent_t
*ent
, char *buffer
, size_t buflen
, const char *user
,
228 gid_t group
, long int *start
, long int *size
,
229 gid_t
**groupsp
, long int limit
, int *errnop
)
231 enum nss_status status
;
234 /* if this module does not support getgrent_r and initgroups_dyn,
235 abort. We cannot find the needed group entries. */
236 if (nss_getgrent_r
== NULL
&& nss_initgroups_dyn
== NULL
)
237 return NSS_STATUS_UNAVAIL
;
239 /* Try nss_initgroups_dyn if supported. We also need getgrgid_r.
240 If this function is not supported, step through the whole group
241 database with getgrent_r. */
242 if (nss_initgroups_dyn
&& nss_getgrgid_r
)
244 long int mystart
= 0;
245 long int mysize
= limit
<= 0 ? *size
: limit
;
246 gid_t
*mygroupsp
= malloc (mysize
* sizeof (gid_t
));
248 if (mygroupsp
== NULL
)
249 return NSS_STATUS_TRYAGAIN
;
251 /* For every gid in the list we get from the NSS module,
252 get the whole group entry. We need to do this, since we
253 need the group name to check if it is in the blacklist.
254 In worst case, this is as twice as slow as stepping with
255 getgrent_r through the whole group database. But for large
256 group databases this is faster, since the user can only be
257 in a limited number of groups. */
258 if (nss_initgroups_dyn (user
, group
, &mystart
, &mysize
, &mygroupsp
,
259 limit
, errnop
) == NSS_STATUS_SUCCESS
)
261 /* A temporary buffer. We use the normal buffer, until we find
262 an entry, for which this buffer is to small. In this case, we
263 overwrite the pointer with one to a bigger buffer. */
264 char *tmpbuf
= buffer
;
265 size_t tmplen
= buflen
;
268 for (i
= 0; i
< mystart
; i
++)
270 while ((status
= nss_getgrgid_r (mygroupsp
[i
], &grpbuf
, tmpbuf
,
272 errnop
)) == NSS_STATUS_TRYAGAIN
273 && *errnop
== ERANGE
)
274 if (tmpbuf
== buffer
)
277 tmpbuf
= __alloca (tmplen
);
280 tmpbuf
= extend_alloca (tmpbuf
, tmplen
, 2 * tmplen
);
282 if (!in_blacklist (grpbuf
.gr_name
,
283 strlen (grpbuf
.gr_name
), ent
))
284 check_and_add_group (user
, group
, start
, size
, groupsp
,
290 return NSS_STATUS_NOTFOUND
;
296 /* If we come here, the NSS module does not support initgroups_dyn
297 and we have to step through the whole list ourself. */
300 if ((status
= nss_getgrent_r (&grpbuf
, buffer
, buflen
, errnop
)) !=
304 while (in_blacklist (grpbuf
.gr_name
, strlen (grpbuf
.gr_name
), ent
));
306 check_and_add_group (user
, group
, start
, size
, groupsp
, limit
, &grpbuf
);
307 return NSS_STATUS_SUCCESS
;
310 static enum nss_status
311 internal_getgrent_r (ent_t
*ent
, char *buffer
, size_t buflen
, const char *user
,
312 gid_t group
, long int *start
, long int *size
,
313 gid_t
**groupsp
, long int limit
, int *errnop
)
315 struct parser_data
*data
= (void *) buffer
;
319 return getgrent_next_nss (ent
, buffer
, buflen
, user
, group
,
320 start
, size
, groupsp
, limit
, errnop
);
330 fgetpos (ent
->stream
, &pos
);
331 buffer
[buflen
- 1] = '\xff';
332 p
= fgets_unlocked (buffer
, buflen
, ent
->stream
);
333 if (p
== NULL
&& feof_unlocked (ent
->stream
))
334 return NSS_STATUS_NOTFOUND
;
336 if (p
== NULL
|| buffer
[buflen
- 1] != '\xff')
338 fsetpos (ent
->stream
, &pos
);
340 return NSS_STATUS_TRYAGAIN
;
343 /* Terminate the line for any case. */
344 buffer
[buflen
- 1] = '\0';
346 /* Skip leading blanks. */
350 while (*p
== '\0' || *p
== '#' || /* Ignore empty and comment lines. */
351 /* Parse the line. If it is invalid, loop to
352 get the next line of the file to parse. */
353 !(parse_res
= _nss_files_parse_grent (p
, &grpbuf
, data
, buflen
,
358 /* The parser ran out of space. */
359 fsetpos (ent
->stream
, &pos
);
361 return NSS_STATUS_TRYAGAIN
;
364 if (grpbuf
.gr_name
[0] != '+' && grpbuf
.gr_name
[0] != '-')
365 /* This is a real entry. */
369 if (grpbuf
.gr_name
[0] == '-' && grpbuf
.gr_name
[1] != '\0'
370 && grpbuf
.gr_name
[1] != '@')
372 blacklist_store_name (&grpbuf
.gr_name
[1], ent
);
377 if (grpbuf
.gr_name
[0] == '+' && grpbuf
.gr_name
[1] != '\0'
378 && grpbuf
.gr_name
[1] != '@')
380 if (in_blacklist (&grpbuf
.gr_name
[1],
381 strlen (&grpbuf
.gr_name
[1]), ent
))
383 /* Store the group in the blacklist for the "+" at the end of
385 blacklist_store_name (&grpbuf
.gr_name
[1], ent
);
386 if (nss_getgrnam_r
== NULL
)
387 return NSS_STATUS_UNAVAIL
;
388 else if (nss_getgrnam_r (&grpbuf
.gr_name
[1], &grpbuf
, buffer
,
389 buflen
, errnop
) != NSS_STATUS_SUCCESS
)
392 check_and_add_group (user
, group
, start
, size
, groupsp
,
395 return NSS_STATUS_SUCCESS
;
399 if (grpbuf
.gr_name
[0] == '+' && grpbuf
.gr_name
[1] == '\0')
402 return getgrent_next_nss (ent
, buffer
, buflen
, user
, group
,
403 start
, size
, groupsp
, limit
, errnop
);
407 check_and_add_group (user
, group
, start
, size
, groupsp
, limit
, &grpbuf
);
409 return NSS_STATUS_SUCCESS
;
414 _nss_compat_initgroups_dyn (const char *user
, gid_t group
, long int *start
,
415 long int *size
, gid_t
**groupsp
, long int limit
,
418 size_t buflen
= sysconf (_SC_GETPW_R_SIZE_MAX
);
420 enum nss_status status
;
421 ent_t intern
= { TRUE
, NULL
, {NULL
, 0, 0} };
423 status
= internal_setgrent (&intern
);
424 if (status
!= NSS_STATUS_SUCCESS
)
427 tmpbuf
= __alloca (buflen
);
431 while ((status
= internal_getgrent_r (&intern
, tmpbuf
, buflen
,
432 user
, group
, start
, size
,
433 groupsp
, limit
, errnop
))
434 == NSS_STATUS_TRYAGAIN
&& *errnop
== ERANGE
)
435 tmpbuf
= extend_alloca (tmpbuf
, buflen
, 2 * buflen
);
437 while (status
== NSS_STATUS_SUCCESS
);
439 internal_endgrent (&intern
);
441 return NSS_STATUS_SUCCESS
;
445 /* Support routines for remembering -@netgroup and -user entries.
446 The names are stored in a single string with `|' as separator. */
448 blacklist_store_name (const char *name
, ent_t
*ent
)
450 int namelen
= strlen (name
);
453 /* First call, setup cache. */
454 if (ent
->blacklist
.size
== 0)
456 ent
->blacklist
.size
= MAX (BLACKLIST_INITIAL_SIZE
, 2 * namelen
);
457 ent
->blacklist
.data
= malloc (ent
->blacklist
.size
);
458 if (ent
->blacklist
.data
== NULL
)
460 ent
->blacklist
.data
[0] = '|';
461 ent
->blacklist
.data
[1] = '\0';
462 ent
->blacklist
.current
= 1;
466 if (in_blacklist (name
, namelen
, ent
))
467 return; /* no duplicates */
469 if (ent
->blacklist
.current
+ namelen
+ 1 >= ent
->blacklist
.size
)
471 ent
->blacklist
.size
+= MAX (BLACKLIST_INCREMENT
, 2 * namelen
);
472 tmp
= realloc (ent
->blacklist
.data
, ent
->blacklist
.size
);
475 free (ent
->blacklist
.data
);
476 ent
->blacklist
.size
= 0;
479 ent
->blacklist
.data
= tmp
;
483 tmp
= stpcpy (ent
->blacklist
.data
+ ent
->blacklist
.current
, name
);
486 ent
->blacklist
.current
+= namelen
+ 1;
491 /* returns TRUE if ent->blacklist contains name, else FALSE */
493 in_blacklist (const char *name
, int namelen
, ent_t
*ent
)
495 char buf
[namelen
+ 3];
498 if (ent
->blacklist
.data
== NULL
)
502 cp
= stpcpy (&buf
[1], name
);
505 return strstr (ent
->blacklist
.data
, buf
) != NULL
;