1 /* Initgroups handling in nss_db module.
2 Copyright (C) 2011-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 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 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If
17 not, see <https://www.gnu.org/licenses/>. */
27 #include <sys/param.h>
31 /* The hashing function we use. */
32 #include "../intl/hash-string.h"
35 _nss_db_initgroups_dyn (const char *user
, gid_t group
, long int *start
,
36 long int *size
, gid_t
**groupsp
, long int limit
,
39 struct nss_db_map state
= { NULL
, 0 };
40 enum nss_status status
= internal_setent (_PATH_VARDB
"group.db", &state
);
41 if (status
!= NSS_STATUS_SUCCESS
)
47 const struct nss_db_header
*header
= state
.header
;
49 for (i
= 0; i
< header
->ndbs
; ++i
)
50 if (header
->dbs
[i
].id
== ':')
52 if (i
== header
->ndbs
)
54 status
= NSS_STATUS_UNAVAIL
;
58 const stridx_t
*hashtable
59 = (const stridx_t
*) ((const char *) header
60 + header
->dbs
[i
].hashoffset
);
61 const char *valstrtab
= (const char *) header
+ header
->valstroffset
;
62 size_t userlen
= strlen (user
);
63 uint32_t hashval
= __hash_string (user
);
64 size_t hidx
= hashval
% header
->dbs
[i
].hashsize
;
65 size_t hval2
= 1 + hashval
% (header
->dbs
[i
].hashsize
- 2);
67 gid_t
*groups
= *groupsp
;
69 status
= NSS_STATUS_NOTFOUND
;
70 while (hashtable
[hidx
] != ~((stridx_t
) 0))
72 const char *valstr
= valstrtab
+ hashtable
[hidx
];
73 while (isblank (*valstr
))
76 if (strncmp (valstr
, user
, userlen
) == 0 && isblank (valstr
[userlen
]))
78 valstr
+= userlen
+ 1;
79 while (isblank (*valstr
))
82 while (*valstr
!= '\0')
86 unsigned long int n
= strtoul (valstr
, &endp
, 10);
87 if (*endp
!= ',' && *endp
!= '\0')
89 valstr
= *endp
== '\0' ? endp
: endp
+ 1;
91 if (n
!= ULONG_MAX
|| errno
!= ERANGE
)
93 /* Insert the group. */
96 /* Need a bigger buffer. */
97 if (limit
> 0 && *size
== limit
)
99 /* We reached the maximum. */
100 status
= NSS_STATUS_SUCCESS
;
108 newsize
= MIN (limit
, 2 * *size
);
110 gid_t
*newgroups
= realloc (groups
,
111 newsize
* sizeof (*groups
));
112 if (newgroups
== NULL
)
115 status
= NSS_STATUS_TRYAGAIN
;
119 *groupsp
= groups
= newgroups
;
128 status
= NSS_STATUS_SUCCESS
;
132 if ((hidx
+= hval2
) >= header
->dbs
[i
].hashsize
)
133 hidx
-= header
->dbs
[i
].hashsize
;
137 internal_endent (&state
);