1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/* Initgroups handling in nss_db module.
Copyright (C) 2011-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, see <http://www.gnu.org/licenses/>. */
#include <ctype.h>
#include <errno.h>
#include <grp.h>
#include <limits.h>
#include <paths.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <sys/param.h>
#include "nss_db.h"
/* The hashing function we use. */
#include "../intl/hash-string.h"
enum nss_status
_nss_db_initgroups_dyn (const char *user, gid_t group, long int *start,
long int *size, gid_t **groupsp, long int limit,
int *errnop)
{
struct nss_db_map state = { NULL, 0 };
enum nss_status status = internal_setent (_PATH_VARDB "group.db", &state);
if (status != NSS_STATUS_SUCCESS)
{
*errnop = errno;
return status;
}
const struct nss_db_header *header = state.header;
int i;
for (i = 0; i < header->ndbs; ++i)
if (header->dbs[i].id == ':')
break;
if (i == header->ndbs)
{
status = NSS_STATUS_UNAVAIL;
goto out;
}
const stridx_t *hashtable
= (const stridx_t *) ((const char *) header
+ header->dbs[i].hashoffset);
const char *valstrtab = (const char *) header + header->valstroffset;
size_t userlen = strlen (user);
uint32_t hashval = __hash_string (user);
size_t hidx = hashval % header->dbs[i].hashsize;
size_t hval2 = 1 + hashval % (header->dbs[i].hashsize - 2);
gid_t *groups = *groupsp;
status = NSS_STATUS_NOTFOUND;
while (hashtable[hidx] != ~((stridx_t) 0))
{
const char *valstr = valstrtab + hashtable[hidx];
while (isblank (*valstr))
++valstr;
if (strncmp (valstr, user, userlen) == 0 && isblank (valstr[userlen]))
{
valstr += userlen + 1;
while (isblank (*valstr))
++valstr;
while (*valstr != '\0')
{
errno = 0;
char *endp;
unsigned long int n = strtoul (valstr, &endp, 10);
if (*endp != ',' && *endp != '\0')
break;
valstr = *endp == '\0' ? endp : endp + 1;
if (n != ULONG_MAX || errno != ERANGE)
{
/* Insert the group. */
if (*start == *size)
{
/* Need a bigger buffer. */
if (limit > 0 && *size == limit)
{
/* We reached the maximum. */
status = NSS_STATUS_SUCCESS;
goto out;
}
long int newsize;
if (limit <= 0)
newsize = 2 * *size;
else
newsize = MIN (limit, 2 * *size);
gid_t *newgroups = realloc (groups,
newsize * sizeof (*groups));
if (newgroups == NULL)
{
*errnop = ENOMEM;
status = NSS_STATUS_TRYAGAIN;
goto out;
}
*groupsp = groups = newgroups;
*size = newsize;
}
groups[*start] = n;
*start += 1;
}
}
status = NSS_STATUS_SUCCESS;
break;
}
if ((hidx += hval2) >= header->dbs[i].hashsize)
hidx -= header->dbs[i].hashsize;
}
out:
internal_endent (&state);
return status;
}
|
GitWeb