1 /*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <sys/stat.h>
18 #include "roots.h"
19 #include "common.h"
20
21 #define CANARY_FILE "/system/build.prop"
22 #define CANARY_FILE_ROOT_PATH "SYSTEM:build.prop"
23
24 int
file_exists(const char * path)25 file_exists(const char *path)
26 {
27 struct stat st;
28 int ret;
29 ret = stat(path, &st);
30 if (ret == 0) {
31 return S_ISREG(st.st_mode);
32 }
33 return 0;
34 }
35
36 int
test_roots()37 test_roots()
38 {
39 int ret;
40
41 /* Make sure that /system isn't mounted yet.
42 */
43 if (file_exists(CANARY_FILE)) return -__LINE__;
44 if (is_root_path_mounted(CANARY_FILE_ROOT_PATH)) return -__LINE__;
45
46 /* Try to mount the root.
47 */
48 ret = ensure_root_path_mounted(CANARY_FILE_ROOT_PATH);
49 if (ret < 0) return -__LINE__;
50
51 /* Make sure we can see the file now and that we know the root is mounted.
52 */
53 if (!file_exists(CANARY_FILE)) return -__LINE__;
54 if (!is_root_path_mounted(CANARY_FILE_ROOT_PATH)) return -__LINE__;
55
56 /* Make sure that the root path corresponds to the regular path.
57 */
58 struct stat st1, st2;
59 char buf[128];
60 const char *path = translate_root_path(CANARY_FILE_ROOT_PATH,
61 buf, sizeof(buf));
62 if (path == NULL) return -__LINE__;
63 ret = stat(CANARY_FILE, &st1);
64 if (ret != 0) return -__LINE__;
65 ret = stat(path, &st2);
66 if (ret != 0) return -__LINE__;
67 if (st1.st_dev != st2.st_dev || st1.st_ino != st2.st_ino) return -__LINE__;
68
69 /* Try to unmount the root.
70 */
71 ret = ensure_root_path_unmounted(CANARY_FILE_ROOT_PATH);
72 if (ret < 0) return -__LINE__;
73
74 /* Make sure that we can't see the file anymore and that
75 * we don't think the root is mounted.
76 */
77 if (file_exists(CANARY_FILE)) return -__LINE__;
78 if (is_root_path_mounted(CANARY_FILE_ROOT_PATH)) return -__LINE__;
79
80 return 0;
81 }
82