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 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 71 Volume* volume_for_path(const char* path) { 72 return fs_mgr_get_entry_for_mount_point(fstab, path); 73 } 74 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, "squashfs") == 0 || 115 strcmp(v->fs_type, "vfat") == 0) { 116 result = mount(v->blk_device, v->mount_point, v->fs_type, 117 v->flags, v->fs_options); 118 if (result == 0) return 0; 119 120 LOGE("failed to mount %s (%s)\n", v->mount_point, strerror(errno)); 121 return -1; 122 } 123 124 LOGE("unknown fs_type \"%s\" for %s\n", v->fs_type, v->mount_point); 125 return -1; 126 } 127 128 int ensure_path_unmounted(const char* path) { 129 Volume* v = volume_for_path(path); 130 if (v == NULL) { 131 LOGE("unknown volume for path [%s]\n", path); 132 return -1; 133 } 134 if (strcmp(v->fs_type, "ramdisk") == 0) { 135 // the ramdisk is always mounted; you can't unmount it. 136 return -1; 137 } 138 139 int result; 140 result = scan_mounted_volumes(); 141 if (result < 0) { 142 LOGE("failed to scan mounted volumes\n"); 143 return -1; 144 } 145 146 const MountedVolume* mv = 147 find_mounted_volume_by_mount_point(v->mount_point); 148 if (mv == NULL) { 149 // volume is already unmounted 150 return 0; 151 } 152 153 return unmount_mounted_volume(mv); 154 } 155 156 static int exec_cmd(const char* path, char* const argv[]) { 157 int status; 158 pid_t child; 159 if ((child = vfork()) == 0) { 160 execv(path, argv); 161 _exit(-1); 162 } 163 waitpid(child, &status, 0); 164 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { 165 LOGE("%s failed with status %d\n", path, WEXITSTATUS(status)); 166 } 167 return WEXITSTATUS(status); 168 } 169 170 int format_volume(const char* volume) { 171 Volume* v = volume_for_path(volume); 172 if (v == NULL) { 173 LOGE("unknown volume \"%s\"\n", volume); 174 return -1; 175 } 176 if (strcmp(v->fs_type, "ramdisk") == 0) { 177 // you can't format the ramdisk. 178 LOGE("can't format_volume \"%s\"", volume); 179 return -1; 180 } 181 if (strcmp(v->mount_point, volume) != 0) { 182 LOGE("can't give path \"%s\" to format_volume\n", volume); 183 return -1; 184 } 185 186 if (ensure_path_unmounted(volume) != 0) { 187 LOGE("format_volume failed to unmount \"%s\"\n", v->mount_point); 188 return -1; 189 } 190 191 if (strcmp(v->fs_type, "yaffs2") == 0 || strcmp(v->fs_type, "mtd") == 0) { 192 mtd_scan_partitions(); 193 const MtdPartition* partition = mtd_find_partition_by_name(v->blk_device); 194 if (partition == NULL) { 195 LOGE("format_volume: no MTD partition \"%s\"\n", v->blk_device); 196 return -1; 197 } 198 199 MtdWriteContext *write = mtd_write_partition(partition); 200 if (write == NULL) { 201 LOGW("format_volume: can't open MTD \"%s\"\n", v->blk_device); 202 return -1; 203 } else if (mtd_erase_blocks(write, -1) == (off_t) -1) { 204 LOGW("format_volume: can't erase MTD \"%s\"\n", v->blk_device); 205 mtd_write_close(write); 206 return -1; 207 } else if (mtd_write_close(write)) { 208 LOGW("format_volume: can't close MTD \"%s\"\n", v->blk_device); 209 return -1; 210 } 211 return 0; 212 } 213 214 if (strcmp(v->fs_type, "ext4") == 0 || strcmp(v->fs_type, "f2fs") == 0) { 215 // if there's a key_loc that looks like a path, it should be a 216 // block device for storing encryption metadata. wipe it too. 217 if (v->key_loc != NULL && v->key_loc[0] == '/') { 218 LOGI("wiping %s\n", v->key_loc); 219 int fd = open(v->key_loc, O_WRONLY | O_CREAT, 0644); 220 if (fd < 0) { 221 LOGE("format_volume: failed to open %s\n", v->key_loc); 222 return -1; 223 } 224 wipe_block_device(fd, get_file_size(fd)); 225 close(fd); 226 } 227 228 ssize_t length = 0; 229 if (v->length != 0) { 230 length = v->length; 231 } else if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0) { 232 length = -CRYPT_FOOTER_OFFSET; 233 } 234 int result; 235 if (strcmp(v->fs_type, "ext4") == 0) { 236 result = make_ext4fs(v->blk_device, length, volume, sehandle); 237 } else { /* Has to be f2fs because we checked earlier. */ 238 if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0 && length < 0) { 239 LOGE("format_volume: crypt footer + negative length (%zd) not supported on %s\n", length, v->fs_type); 240 return -1; 241 } 242 if (length < 0) { 243 LOGE("format_volume: negative length (%zd) not supported on %s\n", length, v->fs_type); 244 return -1; 245 } 246 char *num_sectors; 247 if (asprintf(&num_sectors, "%zd", length / 512) <= 0) { 248 LOGE("format_volume: failed to create %s command for %s\n", v->fs_type, v->blk_device); 249 return -1; 250 } 251 const char *f2fs_path = "/sbin/mkfs.f2fs"; 252 const char* const f2fs_argv[] = {"mkfs.f2fs", "-t", "-d1", v->blk_device, num_sectors, NULL}; 253 254 result = exec_cmd(f2fs_path, (char* const*)f2fs_argv); 255 free(num_sectors); 256 } 257 if (result != 0) { 258 LOGE("format_volume: make %s failed on %s with %d(%s)\n", v->fs_type, v->blk_device, result, strerror(errno)); 259 return -1; 260 } 261 return 0; 262 } 263 264 LOGE("format_volume: fs_type \"%s\" unsupported\n", v->fs_type); 265 return -1; 266 } 267 268 int setup_install_mounts() { 269 if (fstab == NULL) { 270 LOGE("can't set up install mounts: no fstab loaded\n"); 271 return -1; 272 } 273 for (int i = 0; i < fstab->num_entries; ++i) { 274 Volume* v = fstab->recs + i; 275 276 if (strcmp(v->mount_point, "/tmp") == 0 || 277 strcmp(v->mount_point, "/cache") == 0) { 278 if (ensure_path_mounted(v->mount_point) != 0) { 279 LOGE("failed to mount %s\n", v->mount_point); 280 return -1; 281 } 282 283 } else { 284 if (ensure_path_unmounted(v->mount_point) != 0) { 285 LOGE("failed to unmount %s\n", v->mount_point); 286 return -1; 287 } 288 } 289 } 290 return 0; 291 } 292
