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
|
/*
SSSD
Check file permissions
Authors:
Sumit Bose <sbose@redhat.com>
Copyright (C) 2009 Red Hat
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "util/util.h"
static errno_t perform_checks(const char *filename,
struct stat *stat_buf,
uid_t uid, gid_t gid,
mode_t mode, mode_t mask);
errno_t check_file(const char *filename,
uid_t uid, uid_t gid, mode_t mode, mode_t mask,
struct stat *caller_stat_buf, bool follow_symlink)
{
int ret;
struct stat local_stat_buf;
struct stat *stat_buf;
if (caller_stat_buf == NULL) {
stat_buf = &local_stat_buf;
} else {
stat_buf = caller_stat_buf;
}
if (follow_symlink) {
ret = stat(filename, stat_buf);
} else {
ret = lstat(filename, stat_buf);
}
if (ret == -1) {
ret = errno;
DEBUG(SSSDBG_TRACE_FUNC, "lstat for '%s' failed: [%d][%s].\n",
filename, ret, strerror(ret));
return ret;
}
return perform_checks(filename, stat_buf, uid, gid, mode, mask);
}
static errno_t perform_checks(const char *filename,
struct stat *stat_buf,
uid_t uid, gid_t gid,
mode_t mode, mode_t mask)
{
mode_t st_mode;
if (mask) {
st_mode = stat_buf->st_mode & mask;
} else {
st_mode = stat_buf->st_mode & (S_IFMT|ALLPERMS);
}
if ((mode & S_IFMT) != (st_mode & S_IFMT)) {
DEBUG(SSSDBG_TRACE_LIBS, "File '%s' is not of the right type.\n",
filename);
return EINVAL;
}
if ((st_mode & ALLPERMS) != (mode & ALLPERMS)) {
DEBUG(SSSDBG_TRACE_LIBS,
"File '%s' has the wrong (bit masked) mode [%.7o], "
"expected [%.7o].\n", filename,
(st_mode & ALLPERMS), (mode & ALLPERMS));
return EINVAL;
}
if (uid != (uid_t)(-1) && stat_buf->st_uid != uid) {
DEBUG(SSSDBG_TRACE_LIBS, "File '%s' must be owned by uid [%d].\n",
filename, uid);
return EINVAL;
}
if (gid != (gid_t)(-1) && stat_buf->st_gid != gid) {
DEBUG(SSSDBG_TRACE_LIBS, "File '%s' must be owned by gid [%d].\n",
filename, gid);
return EINVAL;
}
return EOK;
}
|
