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 <errno.h>
18 #include <stdlib.h>
19 #include <sys/mount.h>
20 #include <sys/stat.h>
21 #include <sys/types.h>
22 #include <sys/wait.h>
23 #include <unistd.h>
24 #include <ctype.h>
25 #include <fcntl.h>
26
27 #include <fs_mgr.h>
28 #include "mtdutils/mtdutils.h"
29 #include "mtdutils/mounts.h"
30 #include "roots.h"
31 #include "common.h"
32 #include "make_ext4fs.h"
33 extern "C" {
34 #include "wipe.h"
35 #include "cryptfs.h"
36 }
37
38 static struct fstab *fstab = NULL;
39
40 extern struct selabel_handle *sehandle;
41
load_volume_table()42 void load_volume_table()
43 {
44 int i;
45 int ret;
46
47 fstab = fs_mgr_read_fstab("/etc/recovery.fstab");
48 if (!fstab) {
49 LOGE("failed to read /etc/recovery.fstab\n");
50 return;
51 }
52
53 ret = fs_mgr_add_entry(fstab, "/tmp", "ramdisk", "ramdisk");
54 if (ret < 0 ) {
55 LOGE("failed to add /tmp entry to fstab\n");
56 fs_mgr_free_fstab(fstab);
57 fstab = NULL;
58 return;
59 }
60
61 printf("recovery filesystem table\n");
62 printf("=========================\n");
63 for (i = 0; i < fstab->num_entries; ++i) {
64 Volume* v = &fstab->recs[i];
65 printf(" %d %s %s %s %lld\n", i, v->mount_point, v->fs_type,
66 v->blk_device, v->length);
67 }
68 printf("\n");
69 }
70
volume_for_path(const char * path)71 Volume* volume_for_path(const char* path) {
72 return fs_mgr_get_entry_for_mount_point(fstab, path);
73 }
74
ensure_path_mounted(const char * path)75 int ensure_path_mounted(const char* path) {
76 Volume* v = volume_for_path(path);
77 if (v == NULL) {
78 LOGE("unknown volume for path [%s]\n", path);
79 return -1;
80 }
81 if (strcmp(v->fs_type, "ramdisk") == 0) {
82 // the ramdisk is always mounted.
83 return 0;
84 }
85
86 int result;
87 result = scan_mounted_volumes();
88 if (result < 0) {
89 LOGE("failed to scan mounted volumes\n");
90 return -1;
91 }
92
93 const MountedVolume* mv =
94 find_mounted_volume_by_mount_point(v->mount_point);
95 if (mv) {
96 // volume is already mounted
97 return 0;
98 }
99
100 mkdir(v->mount_point, 0755); // in case it doesn't already exist
101
102 if (strcmp(v->fs_type, "yaffs2") == 0) {
103 // mount an MTD partition as a YAFFS2 filesystem.
104 mtd_scan_partitions();
105 const MtdPartition* partition;
106 partition = mtd_find_partition_by_name(v->blk_device);
107 if (partition == NULL) {
108 LOGE("failed to find \"%s\" partition to mount at \"%s\"\n",
109 v->blk_device, v->mount_point);
110 return -1;
111 }
112 return mtd_mount_partition(partition, v->mount_point, v->fs_type, 0);
113 } else if (strcmp(v->fs_type, "ext4") == 0 ||
114 strcmp(v->fs_type, "vfat") == 0) {
115 result = mount(v->blk_device, v->mount_point, v->fs_type,
116 MS_NOATIME | MS_NODEV | MS_NODIRATIME, "");
117 if (result == 0) return 0;
118
119 LOGE("failed to mount %s (%s)\n", v->mount_point, strerror(errno));
120 return -1;
121 }
122
123 LOGE("unknown fs_type \"%s\" for %s\n", v->fs_type, v->mount_point);
124 return -1;
125 }
126
ensure_path_unmounted(const char * path)127 int ensure_path_unmounted(const char* path) {
128 Volume* v = volume_for_path(path);
129 if (v == NULL) {
130 LOGE("unknown volume for path [%s]\n", path);
131 return -1;
132 }
133 if (strcmp(v->fs_type, "ramdisk") == 0) {
134 // the ramdisk is always mounted; you can't unmount it.
135 return -1;
136 }
137
138 int result;
139 result = scan_mounted_volumes();
140 if (result < 0) {
141 LOGE("failed to scan mounted volumes\n");
142 return -1;
143 }
144
145 const MountedVolume* mv =
146 find_mounted_volume_by_mount_point(v->mount_point);
147 if (mv == NULL) {
148 // volume is already unmounted
149 return 0;
150 }
151
152 return unmount_mounted_volume(mv);
153 }
154
exec_cmd(const char * path,char * const argv[])155 static int exec_cmd(const char* path, char* const argv[]) {
156 int status;
157 pid_t child;
158 if ((child = vfork()) == 0) {
159 execv(path, argv);
160 _exit(-1);
161 }
162 waitpid(child, &status, 0);
163 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
164 LOGE("%s failed with status %d\n", path, WEXITSTATUS(status));
165 }
166 return WEXITSTATUS(status);
167 }
168
format_volume(const char * volume)169 int format_volume(const char* volume) {
170 Volume* v = volume_for_path(volume);
171 if (v == NULL) {
172 LOGE("unknown volume \"%s\"\n", volume);
173 return -1;
174 }
175 if (strcmp(v->fs_type, "ramdisk") == 0) {
176 // you can't format the ramdisk.
177 LOGE("can't format_volume \"%s\"", volume);
178 return -1;
179 }
180 if (strcmp(v->mount_point, volume) != 0) {
181 LOGE("can't give path \"%s\" to format_volume\n", volume);
182 return -1;
183 }
184
185 if (ensure_path_unmounted(volume) != 0) {
186 LOGE("format_volume failed to unmount \"%s\"\n", v->mount_point);
187 return -1;
188 }
189
190 if (strcmp(v->fs_type, "yaffs2") == 0 || strcmp(v->fs_type, "mtd") == 0) {
191 mtd_scan_partitions();
192 const MtdPartition* partition = mtd_find_partition_by_name(v->blk_device);
193 if (partition == NULL) {
194 LOGE("format_volume: no MTD partition \"%s\"\n", v->blk_device);
195 return -1;
196 }
197
198 MtdWriteContext *write = mtd_write_partition(partition);
199 if (write == NULL) {
200 LOGW("format_volume: can't open MTD \"%s\"\n", v->blk_device);
201 return -1;
202 } else if (mtd_erase_blocks(write, -1) == (off_t) -1) {
203 LOGW("format_volume: can't erase MTD \"%s\"\n", v->blk_device);
204 mtd_write_close(write);
205 return -1;
206 } else if (mtd_write_close(write)) {
207 LOGW("format_volume: can't close MTD \"%s\"\n", v->blk_device);
208 return -1;
209 }
210 return 0;
211 }
212
213 if (strcmp(v->fs_type, "ext4") == 0 || strcmp(v->fs_type, "f2fs") == 0) {
214 // if there's a key_loc that looks like a path, it should be a
215 // block device for storing encryption metadata. wipe it too.
216 if (v->key_loc != NULL && v->key_loc[0] == '/') {
217 LOGI("wiping %s\n", v->key_loc);
218 int fd = open(v->key_loc, O_WRONLY | O_CREAT, 0644);
219 if (fd < 0) {
220 LOGE("format_volume: failed to open %s\n", v->key_loc);
221 return -1;
222 }
223 wipe_block_device(fd, get_file_size(fd));
224 close(fd);
225 }
226
227 ssize_t length = 0;
228 if (v->length != 0) {
229 length = v->length;
230 } else if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0) {
231 length = -CRYPT_FOOTER_OFFSET;
232 }
233 int result;
234 if (strcmp(v->fs_type, "ext4") == 0) {
235 result = make_ext4fs(v->blk_device, length, volume, sehandle);
236 } else { /* Has to be f2fs because we checked earlier. */
237 if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0 && length < 0) {
238 LOGE("format_volume: crypt footer + negative length (%zd) not supported on %s\n", length, v->fs_type);
239 return -1;
240 }
241 if (length < 0) {
242 LOGE("format_volume: negative length (%zd) not supported on %s\n", length, v->fs_type);
243 return -1;
244 }
245 char *num_sectors;
246 if (asprintf(&num_sectors, "%zd", length / 512) <= 0) {
247 LOGE("format_volume: failed to create %s command for %s\n", v->fs_type, v->blk_device);
248 return -1;
249 }
250 const char *f2fs_path = "/sbin/mkfs.f2fs";
251 const char* const f2fs_argv[] = {"mkfs.f2fs", "-t", "-d1", v->blk_device, num_sectors, NULL};
252
253 result = exec_cmd(f2fs_path, (char* const*)f2fs_argv);
254 free(num_sectors);
255 }
256 if (result != 0) {
257 LOGE("format_volume: make %s failed on %s with %d(%s)\n", v->fs_type, v->blk_device, result, strerror(errno));
258 return -1;
259 }
260 return 0;
261 }
262
263 LOGE("format_volume: fs_type \"%s\" unsupported\n", v->fs_type);
264 return -1;
265 }
266
setup_install_mounts()267 int setup_install_mounts() {
268 if (fstab == NULL) {
269 LOGE("can't set up install mounts: no fstab loaded\n");
270 return -1;
271 }
272 for (int i = 0; i < fstab->num_entries; ++i) {
273 Volume* v = fstab->recs + i;
274
275 if (strcmp(v->mount_point, "/tmp") == 0 ||
276 strcmp(v->mount_point, "/cache") == 0) {
277 if (ensure_path_mounted(v->mount_point) != 0) {
278 LOGE("failed to mount %s\n", v->mount_point);
279 return -1;
280 }
281
282 } else {
283 if (ensure_path_unmounted(v->mount_point) != 0) {
284 LOGE("failed to unmount %s\n", v->mount_point);
285 return -1;
286 }
287 }
288 }
289 return 0;
290 }
291