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
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
/*
SSSD
Check file permissions and open file
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 <fcntl.h>
#include <unistd.h>
#include "util/util.h"
static errno_t perform_checks(struct stat *stat_buf,
const int uid, const int gid,
const int mode, enum check_file_type type);
errno_t check_file(const char *filename, const int uid, const int gid,
const int mode, enum check_file_type type,
struct stat *caller_stat_buf)
{
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;
}
ret = lstat(filename, stat_buf);
if (ret == -1) {
DEBUG(1, ("lstat for [%s] failed: [%d][%s].\n", filename, errno,
strerror(errno)));
return errno;
}
return perform_checks(stat_buf, uid, gid, mode, type);
}
errno_t check_fd(int fd, const int uid, const int gid,
const int mode, enum check_file_type type,
struct stat *caller_stat_buf)
{
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;
}
ret = fstat(fd, stat_buf);
if (ret == -1) {
DEBUG(1, ("fstat for [%d] failed: [%d][%s].\n", fd, errno,
strerror(errno)));
return errno;
}
return perform_checks(stat_buf, uid, gid, mode, type);
}
static errno_t perform_checks(struct stat *stat_buf,
const int uid, const int gid,
const int mode, enum check_file_type type)
{
bool type_check;
switch (type) {
case CHECK_DONT_CHECK_FILE_TYPE:
type_check = true;
break;
case CHECK_REG:
type_check = S_ISREG(stat_buf->st_mode);
break;
case CHECK_DIR:
type_check = S_ISDIR(stat_buf->st_mode);
break;
case CHECK_CHR:
type_check = S_ISCHR(stat_buf->st_mode);
break;
case CHECK_BLK:
type_check = S_ISBLK(stat_buf->st_mode);
break;
case CHECK_FIFO:
type_check = S_ISFIFO(stat_buf->st_mode);
break;
case CHECK_LNK:
type_check = S_ISLNK(stat_buf->st_mode);
break;
case CHECK_SOCK:
type_check = S_ISSOCK(stat_buf->st_mode);
break;
default:
DEBUG(1, ("Unsupported file type.\n"));
return EINVAL;
}
if (!type_check) {
DEBUG(1, ("File is not the right type.\n"));
return EINVAL;
}
if (mode >= 0 && (stat_buf->st_mode & ~S_IFMT) != mode) {
DEBUG(1, ("File has the wrong mode [%.7o], expected [%.7o].\n",
(stat_buf->st_mode & ~S_IFMT), mode));
return EINVAL;
}
if (uid >= 0 && stat_buf->st_uid != uid) {
DEBUG(1, ("File must be owned by uid [%d].\n", uid));
return EINVAL;
}
if (gid >= 0 && stat_buf->st_gid != gid) {
DEBUG(1, ("File must be owned by gid [%d].\n", gid));
return EINVAL;
}
return EOK;
}
errno_t check_and_open_readonly(const char *filename, int *fd, const uid_t uid,
const gid_t gid, const mode_t mode,
enum check_file_type type)
{
int ret;
struct stat stat_buf;
*fd = open(filename, O_RDONLY);
if (*fd == -1) {
DEBUG(1, ("open [%s] failed: [%d][%s].\n", filename, errno,
strerror(errno)));
return errno;
}
ret = check_fd(*fd, uid, gid, mode, type, &stat_buf);
if (ret != EOK) {
close(*fd);
*fd = -1;
DEBUG(1, ("check_fd failed.\n"));
return ret;
}
return EOK;
}
|
