/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <ctype.h>
#include <fcntl.h>
#include <fs_mgr.h>
#include "mtdutils/mtdutils.h"
#include "mtdutils/mounts.h"
#include "roots.h"
#include "common.h"
#include "make_ext4fs.h"
extern "C" {
#include "wipe.h"
#include "cryptfs.h"
}
static struct fstab *fstab = NULL;
extern struct selabel_handle *sehandle;
static const char* PERSISTENT_PATH = "/persistent";
void load_volume_table()
{
int i;
int ret;
fstab = fs_mgr_read_fstab("/etc/recovery.fstab");
if (!fstab) {
LOGE("failed to read /etc/recovery.fstab\n");
return;
}
ret = fs_mgr_add_entry(fstab, "/tmp", "ramdisk", "ramdisk");
if (ret < 0 ) {
LOGE("failed to add /tmp entry to fstab\n");
fs_mgr_free_fstab(fstab);
fstab = NULL;
return;
}
printf("recovery filesystem table\n");
printf("=========================\n");
for (i = 0; i < fstab->num_entries; ++i) {
Volume* v = &fstab->recs[i];
printf(" %d %s %s %s %lld\n", i, v->mount_point, v->fs_type,
v->blk_device, v->length);
}
printf("\n");
}
Volume* volume_for_path(const char* path) {
return fs_mgr_get_entry_for_mount_point(fstab, path);
}
int ensure_path_mounted(const char* path) {
Volume* v = volume_for_path(path);
if (v == NULL) {
LOGE("unknown volume for path [%s]\n", path);
return -1;
}
if (strcmp(v->fs_type, "ramdisk") == 0) {
// the ramdisk is always mounted.
return 0;
}
int result;
result = scan_mounted_volumes();
if (result < 0) {
LOGE("failed to scan mounted volumes\n");
return -1;
}
const MountedVolume* mv =
find_mounted_volume_by_mount_point(v->mount_point);
if (mv) {
// volume is already mounted
return 0;
}
mkdir(v->mount_point, 0755); // in case it doesn't already exist
if (strcmp(v->fs_type, "yaffs2") == 0) {
// mount an MTD partition as a YAFFS2 filesystem.
mtd_scan_partitions();
const MtdPartition* partition;
partition = mtd_find_partition_by_name(v->blk_device);
if (partition == NULL) {
LOGE("failed to find \"%s\" partition to mount at \"%s\"\n",
v->blk_device, v->mount_point);
return -1;
}
return mtd_mount_partition(partition, v->mount_point, v->fs_type, 0);
} else if (strcmp(v->fs_type, "ext4") == 0 ||
strcmp(v->fs_type, "vfat") == 0) {
result = mount(v->blk_device, v->mount_point, v->fs_type,
MS_NOATIME | MS_NODEV | MS_NODIRATIME, "");
if (result == 0) return 0;
LOGE("failed to mount %s (%s)\n", v->mount_point, strerror(errno));
return -1;
}
LOGE("unknown fs_type \"%s\" for %s\n", v->fs_type, v->mount_point);
return -1;
}
int ensure_path_unmounted(const char* path) {
Volume* v = volume_for_path(path);
if (v == NULL) {
LOGE("unknown volume for path [%s]\n", path);
return -1;
}
if (strcmp(v->fs_type, "ramdisk") == 0) {
// the ramdisk is always mounted; you can't unmount it.
return -1;
}
int result;
result = scan_mounted_volumes();
if (result < 0) {
LOGE("failed to scan mounted volumes\n");
return -1;
}
const MountedVolume* mv =
find_mounted_volume_by_mount_point(v->mount_point);
if (mv == NULL) {
// volume is already unmounted
return 0;
}
return unmount_mounted_volume(mv);
}
static int exec_cmd(const char* path, char* const argv[]) {
int status;
pid_t child;
if ((child = vfork()) == 0) {
execv(path, argv);
_exit(-1);
}
waitpid(child, &status, 0);
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
LOGE("%s failed with status %d\n", path, WEXITSTATUS(status));
}
return WEXITSTATUS(status);
}
int format_volume(const char* volume) {
Volume* v = volume_for_path(volume);
if (v == NULL) {
LOGE("unknown volume \"%s\"\n", volume);
return -1;
}
if (strcmp(v->fs_type, "ramdisk") == 0) {
// you can't format the ramdisk.
LOGE("can't format_volume \"%s\"", volume);
return -1;
}
if (strcmp(v->mount_point, volume) != 0) {
LOGE("can't give path \"%s\" to format_volume\n", volume);
return -1;
}
if (ensure_path_unmounted(volume) != 0) {
LOGE("format_volume failed to unmount \"%s\"\n", v->mount_point);
return -1;
}
if (strcmp(v->fs_type, "yaffs2") == 0 || strcmp(v->fs_type, "mtd") == 0) {
mtd_scan_partitions();
const MtdPartition* partition = mtd_find_partition_by_name(v->blk_device);
if (partition == NULL) {
LOGE("format_volume: no MTD partition \"%s\"\n", v->blk_device);
return -1;
}
MtdWriteContext *write = mtd_write_partition(partition);
if (write == NULL) {
LOGW("format_volume: can't open MTD \"%s\"\n", v->blk_device);
return -1;
} else if (mtd_erase_blocks(write, -1) == (off_t) -1) {
LOGW("format_volume: can't erase MTD \"%s\"\n", v->blk_device);
mtd_write_close(write);
return -1;
} else if (mtd_write_close(write)) {
LOGW("format_volume: can't close MTD \"%s\"\n", v->blk_device);
return -1;
}
return 0;
}
if (strcmp(v->fs_type, "ext4") == 0 || strcmp(v->fs_type, "f2fs") == 0) {
// if there's a key_loc that looks like a path, it should be a
// block device for storing encryption metadata. wipe it too.
if (v->key_loc != NULL && v->key_loc[0] == '/') {
LOGI("wiping %s\n", v->key_loc);
int fd = open(v->key_loc, O_WRONLY | O_CREAT, 0644);
if (fd < 0) {
LOGE("format_volume: failed to open %s\n", v->key_loc);
return -1;
}
wipe_block_device(fd, get_file_size(fd));
close(fd);
}
ssize_t length = 0;
if (v->length != 0) {
length = v->length;
} else if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0) {
length = -CRYPT_FOOTER_OFFSET;
}
int result;
if (strcmp(v->fs_type, "ext4") == 0) {
result = make_ext4fs(v->blk_device, length, volume, sehandle);
} else { /* Has to be f2fs because we checked earlier. */
if (v->key_loc != NULL && strcmp(v->key_loc, "footer") == 0 && length < 0) {
LOGE("format_volume: crypt footer + negative length (%zd) not supported on %s\n", length, v->fs_type);
return -1;
}
if (length < 0) {
LOGE("format_volume: negative length (%zd) not supported on %s\n", length, v->fs_type);
return -1;
}
char *num_sectors;
if (asprintf(&num_sectors, "%zd", length / 512) <= 0) {
LOGE("format_volume: failed to create %s command for %s\n", v->fs_type, v->blk_device);
return -1;
}
const char *f2fs_path = "/sbin/mkfs.f2fs";
const char* const f2fs_argv[] = {"mkfs.f2fs", "-t", "-d1", v->blk_device, num_sectors, NULL};
result = exec_cmd(f2fs_path, (char* const*)f2fs_argv);
free(num_sectors);
}
if (result != 0) {
LOGE("format_volume: make %s failed on %s with %d(%s)\n", v->fs_type, v->blk_device, result, strerror(errno));
return -1;
}
return 0;
}
LOGE("format_volume: fs_type \"%s\" unsupported\n", v->fs_type);
return -1;
}
int erase_persistent_partition() {
Volume *v = volume_for_path(PERSISTENT_PATH);
if (v == NULL) {
// most devices won't have /persistent, so this is not an error.
return 0;
}
int fd = open(v->blk_device, O_RDWR);
uint64_t size = get_file_size(fd);
if (size == 0) {
LOGE("failed to stat size of /persistent\n");
close(fd);
return -1;
}
char oem_unlock_enabled;
lseek(fd, size - 1, SEEK_SET);
read(fd, &oem_unlock_enabled, 1);
if (oem_unlock_enabled) {
if (wipe_block_device(fd, size)) {
LOGE("error wiping /persistent: %s\n", strerror(errno));
close(fd);
return -1;
}
lseek(fd, size - 1, SEEK_SET);
write(fd, &oem_unlock_enabled, 1);
}
close(fd);
return (int) oem_unlock_enabled;
}
int setup_install_mounts() {
if (fstab == NULL) {
LOGE("can't set up install mounts: no fstab loaded\n");
return -1;
}
for (int i = 0; i < fstab->num_entries; ++i) {
Volume* v = fstab->recs + i;
if (strcmp(v->mount_point, "/tmp") == 0 ||
strcmp(v->mount_point, "/cache") == 0) {
if (ensure_path_mounted(v->mount_point) != 0) {
LOGE("failed to mount %s\n", v->mount_point);
return -1;
}
} else {
if (ensure_path_unmounted(v->mount_point) != 0) {
LOGE("failed to unmount %s\n", v->mount_point);
return -1;
}
}
}
return 0;
}