/* * Copyright (C) 2012 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 <ctype.h> #include <dirent.h> #include <errno.h> #include <fcntl.h> #include <libgen.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/ioctl.h> #include <sys/mount.h> #include <sys/stat.h> #include <sys/swap.h> #include <sys/types.h> #include <sys/wait.h> #include <time.h> #include <unistd.h> #include <memory> #include <string> #include <thread> #include <vector> #include <android-base/file.h> #include <android-base/properties.h> #include <android-base/stringprintf.h> #include <android-base/strings.h> #include <android-base/unique_fd.h> #include <cutils/android_filesystem_config.h> #include <cutils/android_reboot.h> #include <cutils/partition_utils.h> #include <cutils/properties.h> #include <ext4_utils/ext4.h> #include <ext4_utils/ext4_crypt_init_extensions.h> #include <ext4_utils/ext4_sb.h> #include <ext4_utils/ext4_utils.h> #include <ext4_utils/wipe.h> #include <linux/fs.h> #include <linux/loop.h> #include <linux/magic.h> #include <log/log_properties.h> #include <logwrap/logwrap.h> #include "fs_mgr.h" #include "fs_mgr_avb.h" #include "fs_mgr_priv.h" #include "fs_mgr_priv_dm_ioctl.h" #define KEY_LOC_PROP "ro.crypto.keyfile.userdata" #define KEY_IN_FOOTER "footer" #define E2FSCK_BIN "/system/bin/e2fsck" #define F2FS_FSCK_BIN "/system/bin/fsck.f2fs" #define MKSWAP_BIN "/system/bin/mkswap" #define TUNE2FS_BIN "/system/bin/tune2fs" #define FSCK_LOG_FILE "/dev/fscklogs/log" #define ZRAM_CONF_DEV "/sys/block/zram0/disksize" #define ZRAM_CONF_MCS "/sys/block/zram0/max_comp_streams" #define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a))) // record fs stat enum FsStatFlags { FS_STAT_IS_EXT4 = 0x0001, FS_STAT_NEW_IMAGE_VERSION = 0x0002, FS_STAT_E2FSCK_F_ALWAYS = 0x0004, FS_STAT_UNCLEAN_SHUTDOWN = 0x0008, FS_STAT_QUOTA_ENABLED = 0x0010, FS_STAT_RO_MOUNT_FAILED = 0x0040, FS_STAT_RO_UNMOUNT_FAILED = 0x0080, FS_STAT_FULL_MOUNT_FAILED = 0x0100, FS_STAT_E2FSCK_FAILED = 0x0200, FS_STAT_E2FSCK_FS_FIXED = 0x0400, FS_STAT_EXT4_INVALID_MAGIC = 0x0800, FS_STAT_TOGGLE_QUOTAS_FAILED = 0x10000, FS_STAT_SET_RESERVED_BLOCKS_FAILED = 0x20000, FS_STAT_ENABLE_ENCRYPTION_FAILED = 0x40000, }; // TODO: switch to inotify() bool fs_mgr_wait_for_file(const std::string& filename, const std::chrono::milliseconds relative_timeout) { auto start_time = std::chrono::steady_clock::now(); while (true) { if (!access(filename.c_str(), F_OK) || errno != ENOENT) { return true; } std::this_thread::sleep_for(50ms); auto now = std::chrono::steady_clock::now(); auto time_elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(now - start_time); if (time_elapsed > relative_timeout) return false; } } static void log_fs_stat(const char* blk_device, int fs_stat) { if ((fs_stat & FS_STAT_IS_EXT4) == 0) return; // only log ext4 std::string msg = android::base::StringPrintf("\nfs_stat,%s,0x%x\n", blk_device, fs_stat); android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(FSCK_LOG_FILE, O_WRONLY | O_CLOEXEC | O_APPEND | O_CREAT, 0664))); if (fd == -1 || !android::base::WriteStringToFd(msg, fd)) { LWARNING << __FUNCTION__ << "() cannot log " << msg; } } static bool is_extfs(const std::string& fs_type) { return fs_type == "ext4" || fs_type == "ext3" || fs_type == "ext2"; } static bool should_force_check(int fs_stat) { return fs_stat & (FS_STAT_E2FSCK_F_ALWAYS | FS_STAT_UNCLEAN_SHUTDOWN | FS_STAT_QUOTA_ENABLED | FS_STAT_RO_MOUNT_FAILED | FS_STAT_RO_UNMOUNT_FAILED | FS_STAT_FULL_MOUNT_FAILED | FS_STAT_E2FSCK_FAILED | FS_STAT_TOGGLE_QUOTAS_FAILED | FS_STAT_SET_RESERVED_BLOCKS_FAILED | FS_STAT_ENABLE_ENCRYPTION_FAILED); } static void check_fs(const char *blk_device, char *fs_type, char *target, int *fs_stat) { int status; int ret; long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID; char tmpmnt_opts[64] = "errors=remount-ro"; const char* e2fsck_argv[] = {E2FSCK_BIN, "-y", blk_device}; const char* e2fsck_forced_argv[] = {E2FSCK_BIN, "-f", "-y", blk_device}; /* Check for the types of filesystems we know how to check */ if (is_extfs(fs_type)) { if (*fs_stat & FS_STAT_EXT4_INVALID_MAGIC) { // will fail, so do not try return; } /* * First try to mount and unmount the filesystem. We do this because * the kernel is more efficient than e2fsck in running the journal and * processing orphaned inodes, and on at least one device with a * performance issue in the emmc firmware, it can take e2fsck 2.5 minutes * to do what the kernel does in about a second. * * After mounting and unmounting the filesystem, run e2fsck, and if an * error is recorded in the filesystem superblock, e2fsck will do a full * check. Otherwise, it does nothing. If the kernel cannot mount the * filesytsem due to an error, e2fsck is still run to do a full check * fix the filesystem. */ if (!(*fs_stat & FS_STAT_FULL_MOUNT_FAILED)) { // already tried if full mount failed errno = 0; if (!strcmp(fs_type, "ext4")) { // This option is only valid with ext4 strlcat(tmpmnt_opts, ",nomblk_io_submit", sizeof(tmpmnt_opts)); } ret = mount(blk_device, target, fs_type, tmpmnt_flags, tmpmnt_opts); PINFO << __FUNCTION__ << "(): mount(" << blk_device << "," << target << "," << fs_type << ")=" << ret; if (!ret) { bool umounted = false; int retry_count = 5; while (retry_count-- > 0) { umounted = umount(target) == 0; if (umounted) { LINFO << __FUNCTION__ << "(): unmount(" << target << ") succeeded"; break; } PERROR << __FUNCTION__ << "(): umount(" << target << ") failed"; if (retry_count) sleep(1); } if (!umounted) { // boot may fail but continue and leave it to later stage for now. PERROR << __FUNCTION__ << "(): umount(" << target << ") timed out"; *fs_stat |= FS_STAT_RO_UNMOUNT_FAILED; } } else { *fs_stat |= FS_STAT_RO_MOUNT_FAILED; } } /* * Some system images do not have e2fsck for licensing reasons * (e.g. recent SDK system images). Detect these and skip the check. */ if (access(E2FSCK_BIN, X_OK)) { LINFO << "Not running " << E2FSCK_BIN << " on " << blk_device << " (executable not in system image)"; } else { LINFO << "Running " << E2FSCK_BIN << " on " << blk_device; if (should_force_check(*fs_stat)) { ret = android_fork_execvp_ext( ARRAY_SIZE(e2fsck_forced_argv), const_cast<char**>(e2fsck_forced_argv), &status, true, LOG_KLOG | LOG_FILE, true, const_cast<char*>(FSCK_LOG_FILE), NULL, 0); } else { ret = android_fork_execvp_ext( ARRAY_SIZE(e2fsck_argv), const_cast<char**>(e2fsck_argv), &status, true, LOG_KLOG | LOG_FILE, true, const_cast<char*>(FSCK_LOG_FILE), NULL, 0); } if (ret < 0) { /* No need to check for error in fork, we can't really handle it now */ LERROR << "Failed trying to run " << E2FSCK_BIN; *fs_stat |= FS_STAT_E2FSCK_FAILED; } else if (status != 0) { LINFO << "e2fsck returned status 0x" << std::hex << status; *fs_stat |= FS_STAT_E2FSCK_FS_FIXED; } } } else if (!strcmp(fs_type, "f2fs")) { const char *f2fs_fsck_argv[] = { F2FS_FSCK_BIN, "-a", blk_device }; LINFO << "Running " << F2FS_FSCK_BIN << " -a " << blk_device; ret = android_fork_execvp_ext(ARRAY_SIZE(f2fs_fsck_argv), const_cast<char **>(f2fs_fsck_argv), &status, true, LOG_KLOG | LOG_FILE, true, const_cast<char *>(FSCK_LOG_FILE), NULL, 0); if (ret < 0) { /* No need to check for error in fork, we can't really handle it now */ LERROR << "Failed trying to run " << F2FS_FSCK_BIN; } } return; } static ext4_fsblk_t ext4_blocks_count(const struct ext4_super_block* es) { return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) | le32_to_cpu(es->s_blocks_count_lo); } static ext4_fsblk_t ext4_r_blocks_count(const struct ext4_super_block* es) { return ((ext4_fsblk_t)le32_to_cpu(es->s_r_blocks_count_hi) << 32) | le32_to_cpu(es->s_r_blocks_count_lo); } static bool is_ext4_superblock_valid(const struct ext4_super_block* es) { if (es->s_magic != EXT4_SUPER_MAGIC) return false; if (es->s_rev_level != EXT4_DYNAMIC_REV && es->s_rev_level != EXT4_GOOD_OLD_REV) return false; if (EXT4_INODES_PER_GROUP(es) == 0) return false; return true; } // Read the primary superblock from an ext4 filesystem. On failure return // false. If it's not an ext4 filesystem, also set FS_STAT_EXT4_INVALID_MAGIC. static bool read_ext4_superblock(const char* blk_device, struct ext4_super_block* sb, int* fs_stat) { android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC))); if (fd < 0) { PERROR << "Failed to open '" << blk_device << "'"; return false; } if (pread(fd, sb, sizeof(*sb), 1024) != sizeof(*sb)) { PERROR << "Can't read '" << blk_device << "' superblock"; return false; } if (!is_ext4_superblock_valid(sb)) { LINFO << "Invalid ext4 superblock on '" << blk_device << "'"; // not a valid fs, tune2fs, fsck, and mount will all fail. *fs_stat |= FS_STAT_EXT4_INVALID_MAGIC; return false; } *fs_stat |= FS_STAT_IS_EXT4; LINFO << "superblock s_max_mnt_count:" << sb->s_max_mnt_count << "," << blk_device; if (sb->s_max_mnt_count == 0xffff) { // -1 (int16) in ext2, but uint16 in ext4 *fs_stat |= FS_STAT_NEW_IMAGE_VERSION; } return true; } // Some system images do not have tune2fs for licensing reasons. // Detect these and skip running it. static bool tune2fs_available(void) { return access(TUNE2FS_BIN, X_OK) == 0; } static bool run_tune2fs(const char* argv[], int argc) { int ret; ret = android_fork_execvp_ext(argc, const_cast<char**>(argv), nullptr, true, LOG_KLOG | LOG_FILE, true, nullptr, nullptr, 0); return ret == 0; } // Enable/disable quota support on the filesystem if needed. static void tune_quota(const char* blk_device, const struct fstab_rec* rec, const struct ext4_super_block* sb, int* fs_stat) { bool has_quota = (sb->s_feature_ro_compat & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_QUOTA)) != 0; bool want_quota = fs_mgr_is_quota(rec) != 0; if (has_quota == want_quota) { return; } if (!tune2fs_available()) { LERROR << "Unable to " << (want_quota ? "enable" : "disable") << " quotas on " << blk_device << " because " TUNE2FS_BIN " is missing"; return; } const char* argv[] = {TUNE2FS_BIN, nullptr, nullptr, blk_device}; if (want_quota) { LINFO << "Enabling quotas on " << blk_device; argv[1] = "-Oquota"; argv[2] = "-Qusrquota,grpquota"; *fs_stat |= FS_STAT_QUOTA_ENABLED; } else { LINFO << "Disabling quotas on " << blk_device; argv[1] = "-O^quota"; argv[2] = "-Q^usrquota,^grpquota"; } if (!run_tune2fs(argv, ARRAY_SIZE(argv))) { LERROR << "Failed to run " TUNE2FS_BIN " to " << (want_quota ? "enable" : "disable") << " quotas on " << blk_device; *fs_stat |= FS_STAT_TOGGLE_QUOTAS_FAILED; } } // Set the number of reserved filesystem blocks if needed. static void tune_reserved_size(const char* blk_device, const struct fstab_rec* rec, const struct ext4_super_block* sb, int* fs_stat) { if (!(rec->fs_mgr_flags & MF_RESERVEDSIZE)) { return; } // The size to reserve is given in the fstab, but we won't reserve more // than 2% of the filesystem. const uint64_t max_reserved_blocks = ext4_blocks_count(sb) * 0.02; uint64_t reserved_blocks = rec->reserved_size / EXT4_BLOCK_SIZE(sb); if (reserved_blocks > max_reserved_blocks) { LWARNING << "Reserved blocks " << reserved_blocks << " is too large; " << "capping to " << max_reserved_blocks; reserved_blocks = max_reserved_blocks; } if ((ext4_r_blocks_count(sb) == reserved_blocks) && (sb->s_def_resgid == AID_RESERVED_DISK)) { return; } if (!tune2fs_available()) { LERROR << "Unable to set the number of reserved blocks on " << blk_device << " because " TUNE2FS_BIN " is missing"; return; } LINFO << "Setting reserved block count on " << blk_device << " to " << reserved_blocks; auto reserved_blocks_str = std::to_string(reserved_blocks); auto reserved_gid_str = std::to_string(AID_RESERVED_DISK); const char* argv[] = { TUNE2FS_BIN, "-r", reserved_blocks_str.c_str(), "-g", reserved_gid_str.c_str(), blk_device}; if (!run_tune2fs(argv, ARRAY_SIZE(argv))) { LERROR << "Failed to run " TUNE2FS_BIN " to set the number of reserved blocks on " << blk_device; *fs_stat |= FS_STAT_SET_RESERVED_BLOCKS_FAILED; } } // Enable file-based encryption if needed. static void tune_encrypt(const char* blk_device, const struct fstab_rec* rec, const struct ext4_super_block* sb, int* fs_stat) { bool has_encrypt = (sb->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_ENCRYPT)) != 0; bool want_encrypt = fs_mgr_is_file_encrypted(rec) != 0; if (has_encrypt || !want_encrypt) { return; } if (!tune2fs_available()) { LERROR << "Unable to enable ext4 encryption on " << blk_device << " because " TUNE2FS_BIN " is missing"; return; } const char* argv[] = {TUNE2FS_BIN, "-Oencrypt", blk_device}; LINFO << "Enabling ext4 encryption on " << blk_device; if (!run_tune2fs(argv, ARRAY_SIZE(argv))) { LERROR << "Failed to run " TUNE2FS_BIN " to enable " << "ext4 encryption on " << blk_device; *fs_stat |= FS_STAT_ENABLE_ENCRYPTION_FAILED; } } // // Prepare the filesystem on the given block device to be mounted. // // If the "check" option was given in the fstab record, or it seems that the // filesystem was uncleanly shut down, we'll run fsck on the filesystem. // // If needed, we'll also enable (or disable) filesystem features as specified by // the fstab record. // static int prepare_fs_for_mount(const char* blk_device, const struct fstab_rec* rec) { int fs_stat = 0; if (is_extfs(rec->fs_type)) { struct ext4_super_block sb; if (read_ext4_superblock(blk_device, &sb, &fs_stat)) { if ((sb.s_feature_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) != 0 || (sb.s_state & EXT4_VALID_FS) == 0) { LINFO << "Filesystem on " << blk_device << " was not cleanly shutdown; " << "state flags: 0x" << std::hex << sb.s_state << ", " << "incompat feature flags: 0x" << std::hex << sb.s_feature_incompat; fs_stat |= FS_STAT_UNCLEAN_SHUTDOWN; } // Note: quotas should be enabled before running fsck. tune_quota(blk_device, rec, &sb, &fs_stat); } else { return fs_stat; } } if ((rec->fs_mgr_flags & MF_CHECK) || (fs_stat & (FS_STAT_UNCLEAN_SHUTDOWN | FS_STAT_QUOTA_ENABLED))) { check_fs(blk_device, rec->fs_type, rec->mount_point, &fs_stat); } if (is_extfs(rec->fs_type) && (rec->fs_mgr_flags & (MF_RESERVEDSIZE | MF_FILEENCRYPTION))) { struct ext4_super_block sb; if (read_ext4_superblock(blk_device, &sb, &fs_stat)) { tune_reserved_size(blk_device, rec, &sb, &fs_stat); tune_encrypt(blk_device, rec, &sb, &fs_stat); } } return fs_stat; } static void remove_trailing_slashes(char *n) { int len; len = strlen(n) - 1; while ((*(n + len) == '/') && len) { *(n + len) = '\0'; len--; } } /* * Mark the given block device as read-only, using the BLKROSET ioctl. * Return 0 on success, and -1 on error. */ int fs_mgr_set_blk_ro(const char *blockdev) { int fd; int rc = -1; int ON = 1; fd = TEMP_FAILURE_RETRY(open(blockdev, O_RDONLY | O_CLOEXEC)); if (fd < 0) { // should never happen return rc; } rc = ioctl(fd, BLKROSET, &ON); close(fd); return rc; } // Orange state means the device is unlocked, see the following link for details. // https://source.android.com/security/verifiedboot/verified-boot#device_state bool fs_mgr_is_device_unlocked() { std::string verified_boot_state; if (fs_mgr_get_boot_config("verifiedbootstate", &verified_boot_state)) { return verified_boot_state == "orange"; } return false; } /* * __mount(): wrapper around the mount() system call which also * sets the underlying block device to read-only if the mount is read-only. * See "man 2 mount" for return values. */ static int __mount(const char *source, const char *target, const struct fstab_rec *rec) { unsigned long mountflags = rec->flags; int ret; int save_errno; /* We need this because sometimes we have legacy symlinks * that are lingering around and need cleaning up. */ struct stat info; if (!lstat(target, &info)) if ((info.st_mode & S_IFMT) == S_IFLNK) unlink(target); mkdir(target, 0755); errno = 0; ret = mount(source, target, rec->fs_type, mountflags, rec->fs_options); save_errno = errno; PINFO << __FUNCTION__ << "(source=" << source << ",target=" << target << ",type=" << rec->fs_type << ")=" << ret; if ((ret == 0) && (mountflags & MS_RDONLY) != 0) { fs_mgr_set_blk_ro(source); } errno = save_errno; return ret; } static int fs_match(const char *in1, const char *in2) { char *n1; char *n2; int ret; n1 = strdup(in1); n2 = strdup(in2); remove_trailing_slashes(n1); remove_trailing_slashes(n2); ret = !strcmp(n1, n2); free(n1); free(n2); return ret; } /* * Tries to mount any of the consecutive fstab entries that match * the mountpoint of the one given by fstab->recs[start_idx]. * * end_idx: On return, will be the last rec that was looked at. * attempted_idx: On return, will indicate which fstab rec * succeeded. In case of failure, it will be the start_idx. * Returns * -1 on failure with errno set to match the 1st mount failure. * 0 on success. */ static int mount_with_alternatives(struct fstab *fstab, int start_idx, int *end_idx, int *attempted_idx) { int i; int mount_errno = 0; int mounted = 0; if (!end_idx || !attempted_idx || start_idx >= fstab->num_entries) { errno = EINVAL; if (end_idx) *end_idx = start_idx; if (attempted_idx) *attempted_idx = start_idx; return -1; } /* Hunt down an fstab entry for the same mount point that might succeed */ for (i = start_idx; /* We required that fstab entries for the same mountpoint be consecutive */ i < fstab->num_entries && !strcmp(fstab->recs[start_idx].mount_point, fstab->recs[i].mount_point); i++) { /* * Don't try to mount/encrypt the same mount point again. * Deal with alternate entries for the same point which are required to be all following * each other. */ if (mounted) { LERROR << __FUNCTION__ << "(): skipping fstab dup mountpoint=" << fstab->recs[i].mount_point << " rec[" << i << "].fs_type=" << fstab->recs[i].fs_type << " already mounted as " << fstab->recs[*attempted_idx].fs_type; continue; } int fs_stat = prepare_fs_for_mount(fstab->recs[i].blk_device, &fstab->recs[i]); if (fs_stat & FS_STAT_EXT4_INVALID_MAGIC) { LERROR << __FUNCTION__ << "(): skipping mount, invalid ext4, mountpoint=" << fstab->recs[i].mount_point << " rec[" << i << "].fs_type=" << fstab->recs[i].fs_type; mount_errno = EINVAL; // continue bootup for FDE continue; } int retry_count = 2; while (retry_count-- > 0) { if (!__mount(fstab->recs[i].blk_device, fstab->recs[i].mount_point, &fstab->recs[i])) { *attempted_idx = i; mounted = 1; if (i != start_idx) { LERROR << __FUNCTION__ << "(): Mounted " << fstab->recs[i].blk_device << " on " << fstab->recs[i].mount_point << " with fs_type=" << fstab->recs[i].fs_type << " instead of " << fstab->recs[start_idx].fs_type; } fs_stat &= ~FS_STAT_FULL_MOUNT_FAILED; mount_errno = 0; break; } else { if (retry_count <= 0) break; // run check_fs only once fs_stat |= FS_STAT_FULL_MOUNT_FAILED; /* back up the first errno for crypto decisions */ if (mount_errno == 0) { mount_errno = errno; } // retry after fsck check_fs(fstab->recs[i].blk_device, fstab->recs[i].fs_type, fstab->recs[i].mount_point, &fs_stat); } } log_fs_stat(fstab->recs[i].blk_device, fs_stat); } /* Adjust i for the case where it was still withing the recs[] */ if (i < fstab->num_entries) --i; *end_idx = i; if (!mounted) { *attempted_idx = start_idx; errno = mount_errno; return -1; } return 0; } static int translate_ext_labels(struct fstab_rec *rec) { DIR *blockdir = NULL; struct dirent *ent; char *label; size_t label_len; int ret = -1; if (strncmp(rec->blk_device, "LABEL=", 6)) return 0; label = rec->blk_device + 6; label_len = strlen(label); if (label_len > 16) { LERROR << "FS label is longer than allowed by filesystem"; goto out; } blockdir = opendir("/dev/block"); if (!blockdir) { LERROR << "couldn't open /dev/block"; goto out; } while ((ent = readdir(blockdir))) { int fd; char super_buf[1024]; struct ext4_super_block *sb; if (ent->d_type != DT_BLK) continue; fd = openat(dirfd(blockdir), ent->d_name, O_RDONLY); if (fd < 0) { LERROR << "Cannot open block device /dev/block/" << ent->d_name; goto out; } if (TEMP_FAILURE_RETRY(lseek(fd, 1024, SEEK_SET)) < 0 || TEMP_FAILURE_RETRY(read(fd, super_buf, 1024)) != 1024) { /* Probably a loopback device or something else without a readable * superblock. */ close(fd); continue; } sb = (struct ext4_super_block *)super_buf; if (sb->s_magic != EXT4_SUPER_MAGIC) { LINFO << "/dev/block/" << ent->d_name << " not ext{234}"; continue; } if (!strncmp(label, sb->s_volume_name, label_len)) { char *new_blk_device; if (asprintf(&new_blk_device, "/dev/block/%s", ent->d_name) < 0) { LERROR << "Could not allocate block device string"; goto out; } LINFO << "resolved label " << rec->blk_device << " to " << new_blk_device; free(rec->blk_device); rec->blk_device = new_blk_device; ret = 0; break; } } out: closedir(blockdir); return ret; } static bool needs_block_encryption(const struct fstab_rec* rec) { if (android::base::GetBoolProperty("ro.vold.forceencryption", false) && fs_mgr_is_encryptable(rec)) return true; if (rec->fs_mgr_flags & MF_FORCECRYPT) return true; if (rec->fs_mgr_flags & MF_CRYPT) { /* Check for existence of convert_fde breadcrumb file */ char convert_fde_name[PATH_MAX]; snprintf(convert_fde_name, sizeof(convert_fde_name), "%s/misc/vold/convert_fde", rec->mount_point); if (access(convert_fde_name, F_OK) == 0) return true; } if (rec->fs_mgr_flags & MF_FORCEFDEORFBE) { /* Check for absence of convert_fbe breadcrumb file */ char convert_fbe_name[PATH_MAX]; snprintf(convert_fbe_name, sizeof(convert_fbe_name), "%s/convert_fbe", rec->mount_point); if (access(convert_fbe_name, F_OK) != 0) return true; } return false; } static bool should_use_metadata_encryption(const struct fstab_rec* rec) { if (!(rec->fs_mgr_flags & (MF_FILEENCRYPTION | MF_FORCEFDEORFBE))) return false; if (!(rec->fs_mgr_flags & MF_KEYDIRECTORY)) return false; return true; } // Check to see if a mountable volume has encryption requirements static int handle_encryptable(const struct fstab_rec* rec) { /* If this is block encryptable, need to trigger encryption */ if (needs_block_encryption(rec)) { if (umount(rec->mount_point) == 0) { return FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION; } else { PWARNING << "Could not umount " << rec->mount_point << " - allow continue unencrypted"; return FS_MGR_MNTALL_DEV_NOT_ENCRYPTED; } } else if (should_use_metadata_encryption(rec)) { if (umount(rec->mount_point) == 0) { return FS_MGR_MNTALL_DEV_NEEDS_METADATA_ENCRYPTION; } else { PERROR << "Could not umount " << rec->mount_point << " - fail since can't encrypt"; return FS_MGR_MNTALL_FAIL; } } else if (rec->fs_mgr_flags & (MF_FILEENCRYPTION | MF_FORCEFDEORFBE)) { LINFO << rec->mount_point << " is file encrypted"; return FS_MGR_MNTALL_DEV_FILE_ENCRYPTED; } else if (fs_mgr_is_encryptable(rec)) { return FS_MGR_MNTALL_DEV_NOT_ENCRYPTED; } else { return FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE; } } static bool call_vdc(const std::vector<std::string>& args) { std::vector<char const*> argv; argv.emplace_back("/system/bin/vdc"); for (auto& arg : args) { argv.emplace_back(arg.c_str()); } LOG(INFO) << "Calling: " << android::base::Join(argv, ' '); int ret = android_fork_execvp(4, const_cast<char**>(argv.data()), nullptr, false, true); if (ret != 0) { LOG(ERROR) << "vdc returned error code: " << ret; return false; } LOG(DEBUG) << "vdc finished successfully"; return true; } /* When multiple fstab records share the same mount_point, it will * try to mount each one in turn, and ignore any duplicates after a * first successful mount. * Returns -1 on error, and FS_MGR_MNTALL_* otherwise. */ int fs_mgr_mount_all(struct fstab *fstab, int mount_mode) { int i = 0; int encryptable = FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE; int error_count = 0; int mret = -1; int mount_errno = 0; int attempted_idx = -1; FsManagerAvbUniquePtr avb_handle(nullptr); if (!fstab) { return FS_MGR_MNTALL_FAIL; } for (i = 0; i < fstab->num_entries; i++) { /* Don't mount entries that are managed by vold or not for the mount mode*/ if ((fstab->recs[i].fs_mgr_flags & (MF_VOLDMANAGED | MF_RECOVERYONLY)) || ((mount_mode == MOUNT_MODE_LATE) && !fs_mgr_is_latemount(&fstab->recs[i])) || ((mount_mode == MOUNT_MODE_EARLY) && fs_mgr_is_latemount(&fstab->recs[i]))) { continue; } /* Skip swap and raw partition entries such as boot, recovery, etc */ if (!strcmp(fstab->recs[i].fs_type, "swap") || !strcmp(fstab->recs[i].fs_type, "emmc") || !strcmp(fstab->recs[i].fs_type, "mtd")) { continue; } /* Skip mounting the root partition, as it will already have been mounted */ if (!strcmp(fstab->recs[i].mount_point, "/")) { if ((fstab->recs[i].fs_mgr_flags & MS_RDONLY) != 0) { fs_mgr_set_blk_ro(fstab->recs[i].blk_device); } continue; } /* Translate LABEL= file system labels into block devices */ if (is_extfs(fstab->recs[i].fs_type)) { int tret = translate_ext_labels(&fstab->recs[i]); if (tret < 0) { LERROR << "Could not translate label to block device"; continue; } } if (fstab->recs[i].fs_mgr_flags & MF_WAIT && !fs_mgr_wait_for_file(fstab->recs[i].blk_device, 20s)) { LERROR << "Skipping '" << fstab->recs[i].blk_device << "' during mount_all"; continue; } if (fstab->recs[i].fs_mgr_flags & MF_AVB) { if (!avb_handle) { avb_handle = FsManagerAvbHandle::Open(*fstab); if (!avb_handle) { LERROR << "Failed to open FsManagerAvbHandle"; return FS_MGR_MNTALL_FAIL; } } if (avb_handle->SetUpAvbHashtree(&fstab->recs[i], true /* wait_for_verity_dev */) == SetUpAvbHashtreeResult::kFail) { LERROR << "Failed to set up AVB on partition: " << fstab->recs[i].mount_point << ", skipping!"; /* Skips mounting the device. */ continue; } } else if ((fstab->recs[i].fs_mgr_flags & MF_VERIFY)) { int rc = fs_mgr_setup_verity(&fstab->recs[i], true); if (__android_log_is_debuggable() && (rc == FS_MGR_SETUP_VERITY_DISABLED || rc == FS_MGR_SETUP_VERITY_SKIPPED)) { LINFO << "Verity disabled"; } else if (rc != FS_MGR_SETUP_VERITY_SUCCESS) { LERROR << "Could not set up verified partition, skipping!"; continue; } } int last_idx_inspected; int top_idx = i; mret = mount_with_alternatives(fstab, i, &last_idx_inspected, &attempted_idx); i = last_idx_inspected; mount_errno = errno; /* Deal with encryptability. */ if (!mret) { int status = handle_encryptable(&fstab->recs[attempted_idx]); if (status == FS_MGR_MNTALL_FAIL) { /* Fatal error - no point continuing */ return status; } if (status != FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE) { if (encryptable != FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE) { // Log and continue LERROR << "Only one encryptable/encrypted partition supported"; } encryptable = status; if (status == FS_MGR_MNTALL_DEV_NEEDS_METADATA_ENCRYPTION) { if (!call_vdc( {"cryptfs", "encryptFstab", fstab->recs[attempted_idx].mount_point})) { LERROR << "Encryption failed"; return FS_MGR_MNTALL_FAIL; } } } /* Success! Go get the next one */ continue; } bool wiped = partition_wiped(fstab->recs[top_idx].blk_device); bool crypt_footer = false; if (mret && mount_errno != EBUSY && mount_errno != EACCES && fs_mgr_is_formattable(&fstab->recs[top_idx]) && wiped) { /* top_idx and attempted_idx point at the same partition, but sometimes * at two different lines in the fstab. Use the top one for formatting * as that is the preferred one. */ LERROR << __FUNCTION__ << "(): " << fstab->recs[top_idx].blk_device << " is wiped and " << fstab->recs[top_idx].mount_point << " " << fstab->recs[top_idx].fs_type << " is formattable. Format it."; if (fs_mgr_is_encryptable(&fstab->recs[top_idx]) && strcmp(fstab->recs[top_idx].key_loc, KEY_IN_FOOTER)) { int fd = open(fstab->recs[top_idx].key_loc, O_WRONLY); if (fd >= 0) { LINFO << __FUNCTION__ << "(): also wipe " << fstab->recs[top_idx].key_loc; wipe_block_device(fd, get_file_size(fd)); close(fd); } else { PERROR << __FUNCTION__ << "(): " << fstab->recs[top_idx].key_loc << " wouldn't open"; } } else if (fs_mgr_is_encryptable(&fstab->recs[top_idx]) && !strcmp(fstab->recs[top_idx].key_loc, KEY_IN_FOOTER)) { crypt_footer = true; } if (fs_mgr_do_format(&fstab->recs[top_idx], crypt_footer) == 0) { /* Let's replay the mount actions. */ i = top_idx - 1; continue; } else { LERROR << __FUNCTION__ << "(): Format failed. " << "Suggest recovery..."; encryptable = FS_MGR_MNTALL_DEV_NEEDS_RECOVERY; continue; } } /* mount(2) returned an error, handle the encryptable/formattable case */ if (mret && mount_errno != EBUSY && mount_errno != EACCES && fs_mgr_is_encryptable(&fstab->recs[attempted_idx])) { if (wiped) { LERROR << __FUNCTION__ << "(): " << fstab->recs[attempted_idx].blk_device << " is wiped and " << fstab->recs[attempted_idx].mount_point << " " << fstab->recs[attempted_idx].fs_type << " is encryptable. Suggest recovery..."; encryptable = FS_MGR_MNTALL_DEV_NEEDS_RECOVERY; continue; } else { /* Need to mount a tmpfs at this mountpoint for now, and set * properties that vold will query later for decrypting */ LERROR << __FUNCTION__ << "(): possibly an encryptable blkdev " << fstab->recs[attempted_idx].blk_device << " for mount " << fstab->recs[attempted_idx].mount_point << " type " << fstab->recs[attempted_idx].fs_type; if (fs_mgr_do_tmpfs_mount(fstab->recs[attempted_idx].mount_point) < 0) { ++error_count; continue; } } encryptable = FS_MGR_MNTALL_DEV_MIGHT_BE_ENCRYPTED; } else if (mret && mount_errno != EBUSY && mount_errno != EACCES && should_use_metadata_encryption(&fstab->recs[attempted_idx])) { if (!call_vdc({"cryptfs", "mountFstab", fstab->recs[attempted_idx].mount_point})) { ++error_count; } encryptable = FS_MGR_MNTALL_DEV_IS_METADATA_ENCRYPTED; continue; } else { // fs_options might be null so we cannot use PERROR << directly. // Use StringPrintf to output "(null)" instead. if (fs_mgr_is_nofail(&fstab->recs[attempted_idx])) { PERROR << android::base::StringPrintf( "Ignoring failure to mount an un-encryptable or wiped " "partition on %s at %s options: %s", fstab->recs[attempted_idx].blk_device, fstab->recs[attempted_idx].mount_point, fstab->recs[attempted_idx].fs_options); } else { PERROR << android::base::StringPrintf( "Failed to mount an un-encryptable or wiped partition " "on %s at %s options: %s", fstab->recs[attempted_idx].blk_device, fstab->recs[attempted_idx].mount_point, fstab->recs[attempted_idx].fs_options); ++error_count; } continue; } } if (error_count) { return FS_MGR_MNTALL_FAIL; } else { return encryptable; } } /* wrapper to __mount() and expects a fully prepared fstab_rec, * unlike fs_mgr_do_mount which does more things with avb / verity * etc. */ int fs_mgr_do_mount_one(struct fstab_rec *rec) { if (!rec) { return FS_MGR_DOMNT_FAILED; } int ret = __mount(rec->blk_device, rec->mount_point, rec); if (ret) { ret = (errno == EBUSY) ? FS_MGR_DOMNT_BUSY : FS_MGR_DOMNT_FAILED; } return ret; } /* If tmp_mount_point is non-null, mount the filesystem there. This is for the * tmp mount we do to check the user password * If multiple fstab entries are to be mounted on "n_name", it will try to mount each one * in turn, and stop on 1st success, or no more match. */ int fs_mgr_do_mount(struct fstab *fstab, const char *n_name, char *n_blk_device, char *tmp_mount_point) { int i = 0; int mount_errors = 0; int first_mount_errno = 0; char* mount_point; FsManagerAvbUniquePtr avb_handle(nullptr); if (!fstab) { return FS_MGR_DOMNT_FAILED; } for (i = 0; i < fstab->num_entries; i++) { if (!fs_match(fstab->recs[i].mount_point, n_name)) { continue; } /* We found our match */ /* If this swap or a raw partition, report an error */ if (!strcmp(fstab->recs[i].fs_type, "swap") || !strcmp(fstab->recs[i].fs_type, "emmc") || !strcmp(fstab->recs[i].fs_type, "mtd")) { LERROR << "Cannot mount filesystem of type " << fstab->recs[i].fs_type << " on " << n_blk_device; return FS_MGR_DOMNT_FAILED; } /* First check the filesystem if requested */ if (fstab->recs[i].fs_mgr_flags & MF_WAIT && !fs_mgr_wait_for_file(n_blk_device, 20s)) { LERROR << "Skipping mounting '" << n_blk_device << "'"; continue; } int fs_stat = prepare_fs_for_mount(n_blk_device, &fstab->recs[i]); if (fstab->recs[i].fs_mgr_flags & MF_AVB) { if (!avb_handle) { avb_handle = FsManagerAvbHandle::Open(*fstab); if (!avb_handle) { LERROR << "Failed to open FsManagerAvbHandle"; return FS_MGR_DOMNT_FAILED; } } if (avb_handle->SetUpAvbHashtree(&fstab->recs[i], true /* wait_for_verity_dev */) == SetUpAvbHashtreeResult::kFail) { LERROR << "Failed to set up AVB on partition: " << fstab->recs[i].mount_point << ", skipping!"; /* Skips mounting the device. */ continue; } } else if ((fstab->recs[i].fs_mgr_flags & MF_VERIFY)) { int rc = fs_mgr_setup_verity(&fstab->recs[i], true); if (__android_log_is_debuggable() && (rc == FS_MGR_SETUP_VERITY_DISABLED || rc == FS_MGR_SETUP_VERITY_SKIPPED)) { LINFO << "Verity disabled"; } else if (rc != FS_MGR_SETUP_VERITY_SUCCESS) { LERROR << "Could not set up verified partition, skipping!"; continue; } } /* Now mount it where requested */ if (tmp_mount_point) { mount_point = tmp_mount_point; } else { mount_point = fstab->recs[i].mount_point; } int retry_count = 2; while (retry_count-- > 0) { if (!__mount(n_blk_device, mount_point, &fstab->recs[i])) { fs_stat &= ~FS_STAT_FULL_MOUNT_FAILED; return FS_MGR_DOMNT_SUCCESS; } else { if (retry_count <= 0) break; // run check_fs only once if (!first_mount_errno) first_mount_errno = errno; mount_errors++; fs_stat |= FS_STAT_FULL_MOUNT_FAILED; // try again after fsck check_fs(n_blk_device, fstab->recs[i].fs_type, fstab->recs[i].mount_point, &fs_stat); } } log_fs_stat(fstab->recs[i].blk_device, fs_stat); } // Reach here means the mount attempt fails. if (mount_errors) { PERROR << "Cannot mount filesystem on " << n_blk_device << " at " << mount_point; if (first_mount_errno == EBUSY) return FS_MGR_DOMNT_BUSY; } else { /* We didn't find a match, say so and return an error */ LERROR << "Cannot find mount point " << n_name << " in fstab"; } return FS_MGR_DOMNT_FAILED; } /* * mount a tmpfs filesystem at the given point. * return 0 on success, non-zero on failure. */ int fs_mgr_do_tmpfs_mount(const char *n_name) { int ret; ret = mount("tmpfs", n_name, "tmpfs", MS_NOATIME | MS_NOSUID | MS_NODEV, CRYPTO_TMPFS_OPTIONS); if (ret < 0) { LERROR << "Cannot mount tmpfs filesystem at " << n_name; return -1; } /* Success */ return 0; } int fs_mgr_unmount_all(struct fstab *fstab) { int i = 0; int ret = 0; if (!fstab) { return -1; } while (fstab->recs[i].blk_device) { if (umount(fstab->recs[i].mount_point)) { LERROR << "Cannot unmount filesystem at " << fstab->recs[i].mount_point; ret = -1; } i++; } return ret; } /* This must be called after mount_all, because the mkswap command needs to be * available. */ int fs_mgr_swapon_all(struct fstab *fstab) { int i = 0; int flags = 0; int err = 0; int ret = 0; int status; const char *mkswap_argv[2] = { MKSWAP_BIN, nullptr }; if (!fstab) { return -1; } for (i = 0; i < fstab->num_entries; i++) { /* Skip non-swap entries */ if (strcmp(fstab->recs[i].fs_type, "swap")) { continue; } if (fstab->recs[i].zram_size > 0) { /* A zram_size was specified, so we need to configure the * device. There is no point in having multiple zram devices * on a system (all the memory comes from the same pool) so * we can assume the device number is 0. */ FILE *zram_fp; FILE *zram_mcs_fp; if (fstab->recs[i].max_comp_streams >= 0) { zram_mcs_fp = fopen(ZRAM_CONF_MCS, "r+"); if (zram_mcs_fp == NULL) { LERROR << "Unable to open zram conf comp device " << ZRAM_CONF_MCS; ret = -1; continue; } fprintf(zram_mcs_fp, "%d\n", fstab->recs[i].max_comp_streams); fclose(zram_mcs_fp); } zram_fp = fopen(ZRAM_CONF_DEV, "r+"); if (zram_fp == NULL) { LERROR << "Unable to open zram conf device " << ZRAM_CONF_DEV; ret = -1; continue; } fprintf(zram_fp, "%u\n", fstab->recs[i].zram_size); fclose(zram_fp); } if (fstab->recs[i].fs_mgr_flags & MF_WAIT && !fs_mgr_wait_for_file(fstab->recs[i].blk_device, 20s)) { LERROR << "Skipping mkswap for '" << fstab->recs[i].blk_device << "'"; ret = -1; continue; } /* Initialize the swap area */ mkswap_argv[1] = fstab->recs[i].blk_device; err = android_fork_execvp_ext(ARRAY_SIZE(mkswap_argv), const_cast<char **>(mkswap_argv), &status, true, LOG_KLOG, false, NULL, NULL, 0); if (err) { LERROR << "mkswap failed for " << fstab->recs[i].blk_device; ret = -1; continue; } /* If -1, then no priority was specified in fstab, so don't set * SWAP_FLAG_PREFER or encode the priority */ if (fstab->recs[i].swap_prio >= 0) { flags = (fstab->recs[i].swap_prio << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK; flags |= SWAP_FLAG_PREFER; } else { flags = 0; } err = swapon(fstab->recs[i].blk_device, flags); if (err) { LERROR << "swapon failed for " << fstab->recs[i].blk_device; ret = -1; } } return ret; } struct fstab_rec const* fs_mgr_get_crypt_entry(struct fstab const* fstab) { int i; if (!fstab) { return NULL; } /* Look for the encryptable partition to find the data */ for (i = 0; i < fstab->num_entries; i++) { /* Don't deal with vold managed enryptable partitions here */ if (!(fstab->recs[i].fs_mgr_flags & MF_VOLDMANAGED) && (fstab->recs[i].fs_mgr_flags & (MF_CRYPT | MF_FORCECRYPT | MF_FORCEFDEORFBE | MF_FILEENCRYPTION))) { return &fstab->recs[i]; } } return NULL; } /* * key_loc must be at least PROPERTY_VALUE_MAX bytes long * * real_blk_device must be at least PROPERTY_VALUE_MAX bytes long */ void fs_mgr_get_crypt_info(struct fstab* fstab, char* key_loc, char* real_blk_device, size_t size) { struct fstab_rec const* rec = fs_mgr_get_crypt_entry(fstab); if (key_loc) { if (rec) { strlcpy(key_loc, rec->key_loc, size); } else { *key_loc = '\0'; } } if (real_blk_device) { if (rec) { strlcpy(real_blk_device, rec->blk_device, size); } else { *real_blk_device = '\0'; } } } bool fs_mgr_load_verity_state(int* mode) { /* return the default mode, unless any of the verified partitions are in * logging mode, in which case return that */ *mode = VERITY_MODE_DEFAULT; std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> fstab(fs_mgr_read_fstab_default(), fs_mgr_free_fstab); if (!fstab) { LERROR << "Failed to read default fstab"; return false; } for (int i = 0; i < fstab->num_entries; i++) { if (fs_mgr_is_avb(&fstab->recs[i])) { *mode = VERITY_MODE_RESTART; // avb only supports restart mode. break; } else if (!fs_mgr_is_verified(&fstab->recs[i])) { continue; } int current; if (load_verity_state(&fstab->recs[i], ¤t) < 0) { continue; } if (current != VERITY_MODE_DEFAULT) { *mode = current; break; } } return true; } bool fs_mgr_update_verity_state(fs_mgr_verity_state_callback callback) { if (!callback) { return false; } int mode; if (!fs_mgr_load_verity_state(&mode)) { return false; } android::base::unique_fd fd(TEMP_FAILURE_RETRY(open("/dev/device-mapper", O_RDWR | O_CLOEXEC))); if (fd == -1) { PERROR << "Error opening device mapper"; return false; } std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> fstab(fs_mgr_read_fstab_default(), fs_mgr_free_fstab); if (!fstab) { LERROR << "Failed to read default fstab"; return false; } alignas(dm_ioctl) char buffer[DM_BUF_SIZE]; struct dm_ioctl* io = (struct dm_ioctl*)buffer; bool system_root = android::base::GetProperty("ro.build.system_root_image", "") == "true"; for (int i = 0; i < fstab->num_entries; i++) { if (!fs_mgr_is_verified(&fstab->recs[i]) && !fs_mgr_is_avb(&fstab->recs[i])) { continue; } std::string mount_point; if (system_root && !strcmp(fstab->recs[i].mount_point, "/")) { // In AVB, the dm device name is vroot instead of system. mount_point = fs_mgr_is_avb(&fstab->recs[i]) ? "vroot" : "system"; } else { mount_point = basename(fstab->recs[i].mount_point); } fs_mgr_verity_ioctl_init(io, mount_point, 0); const char* status; if (ioctl(fd, DM_TABLE_STATUS, io)) { if (fstab->recs[i].fs_mgr_flags & MF_VERIFYATBOOT) { status = "V"; } else { PERROR << "Failed to query DM_TABLE_STATUS for " << mount_point.c_str(); continue; } } status = &buffer[io->data_start + sizeof(struct dm_target_spec)]; // To be consistent in vboot 1.0 and vboot 2.0 (AVB), change the mount_point // back to 'system' for the callback. So it has property [partition.system.verified] // instead of [partition.vroot.verified]. if (mount_point == "vroot") mount_point = "system"; if (*status == 'C' || *status == 'V') { callback(&fstab->recs[i], mount_point.c_str(), mode, *status); } } return true; }