diff options
Diffstat (limited to 'crypto/fs_mgr/fs_mgr.c')
| -rw-r--r-- | crypto/fs_mgr/fs_mgr.c | 948 |
1 files changed, 948 insertions, 0 deletions
diff --git a/crypto/fs_mgr/fs_mgr.c b/crypto/fs_mgr/fs_mgr.c new file mode 100644 index 000000000..3aa9e6039 --- /dev/null +++ b/crypto/fs_mgr/fs_mgr.c @@ -0,0 +1,948 @@ +/* + * 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 <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <ctype.h> +#include <sys/mount.h> +#include <sys/stat.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <libgen.h> +#include <time.h> +//#include <sys/swap.h> +/* XXX These need to be obtained from kernel headers. See b/9336527 */ +#define SWAP_FLAG_PREFER 0x8000 +#define SWAP_FLAG_PRIO_MASK 0x7fff +#define SWAP_FLAG_PRIO_SHIFT 0 +#define SWAP_FLAG_DISCARD 0x10000 + +#include <linux/loop.h> +#include <private/android_filesystem_config.h> +#include <cutils/partition_utils.h> +#include <cutils/properties.h> +#include <logwrap/logwrap.h> + +#include "mincrypt/rsa.h" +#include "mincrypt/sha.h" +#include "mincrypt/sha256.h" + +#include "fs_mgr_priv.h" +#include "fs_mgr_priv_verity.h" + +#define KEY_LOC_PROP "ro.crypto.keyfile.userdata" +#define KEY_IN_FOOTER "footer" + +#define E2FSCK_BIN "/system/bin/e2fsck" +#define MKSWAP_BIN "/system/bin/mkswap" + +#define FSCK_LOG_FILE "/dev/fscklogs/log" + +#define ZRAM_CONF_DEV "/sys/block/zram0/disksize" + +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a))) + +struct flag_list { + const char *name; + unsigned flag; +}; + +static struct flag_list mount_flags[] = { + { "noatime", MS_NOATIME }, + { "noexec", MS_NOEXEC }, + { "nosuid", MS_NOSUID }, + { "nodev", MS_NODEV }, + { "nodiratime", MS_NODIRATIME }, + { "ro", MS_RDONLY }, + { "rw", 0 }, + { "remount", MS_REMOUNT }, + { "bind", MS_BIND }, + { "rec", MS_REC }, + { "unbindable", MS_UNBINDABLE }, + { "private", MS_PRIVATE }, + { "slave", MS_SLAVE }, + { "shared", MS_SHARED }, + { "defaults", 0 }, + { 0, 0 }, +}; + +static struct flag_list fs_mgr_flags[] = { + { "wait", MF_WAIT }, + { "check", MF_CHECK }, + { "encryptable=",MF_CRYPT }, + { "nonremovable",MF_NONREMOVABLE }, + { "voldmanaged=",MF_VOLDMANAGED}, + { "length=", MF_LENGTH }, + { "recoveryonly",MF_RECOVERYONLY }, + { "swapprio=", MF_SWAPPRIO }, + { "zramsize=", MF_ZRAMSIZE }, + { "verify", MF_VERIFY }, + { "noemulatedsd", MF_NOEMULATEDSD }, + { "defaults", 0 }, + { 0, 0 }, +}; + +struct fs_mgr_flag_values { + char *key_loc; + long long part_length; + char *label; + int partnum; + int swap_prio; + unsigned int zram_size; +}; + +/* + * gettime() - returns the time in seconds of the system's monotonic clock or + * zero on error. + */ +static time_t gettime(void) +{ + struct timespec ts; + int ret; + + ret = clock_gettime(CLOCK_MONOTONIC, &ts); + if (ret < 0) { + ERROR("clock_gettime(CLOCK_MONOTONIC) failed: %s\n", strerror(errno)); + return 0; + } + + return ts.tv_sec; +} + +static int wait_for_file(const char *filename, int timeout) +{ + struct stat info; + time_t timeout_time = gettime() + timeout; + int ret = -1; + + while (gettime() < timeout_time && ((ret = stat(filename, &info)) < 0)) + usleep(10000); + + return ret; +} + +static int parse_flags(char *flags, struct flag_list *fl, + struct fs_mgr_flag_values *flag_vals, + char *fs_options, int fs_options_len) +{ + int f = 0; + int i; + char *p; + char *savep; + + /* initialize flag values. If we find a relevant flag, we'll + * update the value */ + if (flag_vals) { + memset(flag_vals, 0, sizeof(*flag_vals)); + flag_vals->partnum = -1; + flag_vals->swap_prio = -1; /* negative means it wasn't specified. */ + } + + /* initialize fs_options to the null string */ + if (fs_options && (fs_options_len > 0)) { + fs_options[0] = '\0'; + } + + p = strtok_r(flags, ",", &savep); + while (p) { + /* Look for the flag "p" in the flag list "fl" + * If not found, the loop exits with fl[i].name being null. + */ + for (i = 0; fl[i].name; i++) { + if (!strncmp(p, fl[i].name, strlen(fl[i].name))) { + f |= fl[i].flag; + if ((fl[i].flag == MF_CRYPT) && flag_vals) { + /* The encryptable flag is followed by an = and the + * location of the keys. Get it and return it. + */ + flag_vals->key_loc = strdup(strchr(p, '=') + 1); + } else if ((fl[i].flag == MF_LENGTH) && flag_vals) { + /* The length flag is followed by an = and the + * size of the partition. Get it and return it. + */ + flag_vals->part_length = strtoll(strchr(p, '=') + 1, NULL, 0); + } else if ((fl[i].flag == MF_VOLDMANAGED) && flag_vals) { + /* The voldmanaged flag is followed by an = and the + * label, a colon and the partition number or the + * word "auto", e.g. + * voldmanaged=sdcard:3 + * Get and return them. + */ + char *label_start; + char *label_end; + char *part_start; + + label_start = strchr(p, '=') + 1; + label_end = strchr(p, ':'); + if (label_end) { + flag_vals->label = strndup(label_start, + (int) (label_end - label_start)); + part_start = strchr(p, ':') + 1; + if (!strcmp(part_start, "auto")) { + flag_vals->partnum = -1; + } else { + flag_vals->partnum = strtol(part_start, NULL, 0); + } + } else { + ERROR("Warning: voldmanaged= flag malformed\n"); + } + } else if ((fl[i].flag == MF_SWAPPRIO) && flag_vals) { + flag_vals->swap_prio = strtoll(strchr(p, '=') + 1, NULL, 0); + } else if ((fl[i].flag == MF_ZRAMSIZE) && flag_vals) { + flag_vals->zram_size = strtoll(strchr(p, '=') + 1, NULL, 0); + } + break; + } + } + + if (!fl[i].name) { + if (fs_options) { + /* It's not a known flag, so it must be a filesystem specific + * option. Add it to fs_options if it was passed in. + */ + strlcat(fs_options, p, fs_options_len); + strlcat(fs_options, ",", fs_options_len); + } else { + /* fs_options was not passed in, so if the flag is unknown + * it's an error. + */ + ERROR("Warning: unknown flag %s\n", p); + } + } + p = strtok_r(NULL, ",", &savep); + } + +out: + if (fs_options && fs_options[0]) { + /* remove the last trailing comma from the list of options */ + fs_options[strlen(fs_options) - 1] = '\0'; + } + + return f; +} + +/* Read a line of text till the next newline character. + * If no newline is found before the buffer is full, continue reading till a new line is seen, + * then return an empty buffer. This effectively ignores lines that are too long. + * On EOF, return null. + */ +static char *fs_getline(char *buf, int size, FILE *file) +{ + int cnt = 0; + int eof = 0; + int eol = 0; + int c; + + if (size < 1) { + return NULL; + } + + while (cnt < (size - 1)) { + c = getc(file); + if (c == EOF) { + eof = 1; + break; + } + + *(buf + cnt) = c; + cnt++; + + if (c == '\n') { + eol = 1; + break; + } + } + + /* Null terminate what we've read */ + *(buf + cnt) = '\0'; + + if (eof) { + if (cnt) { + return buf; + } else { + return NULL; + } + } else if (eol) { + return buf; + } else { + /* The line is too long. Read till a newline or EOF. + * If EOF, return null, if newline, return an empty buffer. + */ + while(1) { + c = getc(file); + if (c == EOF) { + return NULL; + } else if (c == '\n') { + *buf = '\0'; + return buf; + } + } + } +} + +struct fstab *fs_mgr_read_fstab(const char *fstab_path) +{ + FILE *fstab_file; + int cnt, entries; + int len; + char line[256]; + const char *delim = " \t"; + char *save_ptr, *p; + struct fstab *fstab; + struct fstab_rec *recs; + struct fs_mgr_flag_values flag_vals; +#define FS_OPTIONS_LEN 1024 + char tmp_fs_options[FS_OPTIONS_LEN]; + + fstab_file = fopen(fstab_path, "r"); + if (!fstab_file) { + ERROR("Cannot open file %s\n", fstab_path); + return 0; + } + + entries = 0; + while (fs_getline(line, sizeof(line), fstab_file)) { + /* if the last character is a newline, shorten the string by 1 byte */ + len = strlen(line); + if (line[len - 1] == '\n') { + line[len - 1] = '\0'; + } + /* Skip any leading whitespace */ + p = line; + while (isspace(*p)) { + p++; + } + /* ignore comments or empty lines */ + if (*p == '#' || *p == '\0') + continue; + entries++; + } + + if (!entries) { + ERROR("No entries found in fstab\n"); + return 0; + } + + /* Allocate and init the fstab structure */ + fstab = calloc(1, sizeof(struct fstab)); + fstab->num_entries = entries; + fstab->fstab_filename = strdup(fstab_path); + fstab->recs = calloc(fstab->num_entries, sizeof(struct fstab_rec)); + + fseek(fstab_file, 0, SEEK_SET); + + cnt = 0; + while (fs_getline(line, sizeof(line), fstab_file)) { + /* if the last character is a newline, shorten the string by 1 byte */ + len = strlen(line); + if (line[len - 1] == '\n') { + line[len - 1] = '\0'; + } + + /* Skip any leading whitespace */ + p = line; + while (isspace(*p)) { + p++; + } + /* ignore comments or empty lines */ + if (*p == '#' || *p == '\0') + continue; + + /* If a non-comment entry is greater than the size we allocated, give an + * error and quit. This can happen in the unlikely case the file changes + * between the two reads. + */ + if (cnt >= entries) { + ERROR("Tried to process more entries than counted\n"); + break; + } + + if (!(p = strtok_r(line, delim, &save_ptr))) { + ERROR("Error parsing mount source\n"); + return 0; + } + fstab->recs[cnt].blk_device = strdup(p); + + if (!(p = strtok_r(NULL, delim, &save_ptr))) { + ERROR("Error parsing mount_point\n"); + return 0; + } + fstab->recs[cnt].mount_point = strdup(p); + + if (!(p = strtok_r(NULL, delim, &save_ptr))) { + ERROR("Error parsing fs_type\n"); + return 0; + } + fstab->recs[cnt].fs_type = strdup(p); + + if (!(p = strtok_r(NULL, delim, &save_ptr))) { + ERROR("Error parsing mount_flags\n"); + return 0; + } + tmp_fs_options[0] = '\0'; + fstab->recs[cnt].flags = parse_flags(p, mount_flags, NULL, + tmp_fs_options, FS_OPTIONS_LEN); + + /* fs_options are optional */ + if (tmp_fs_options[0]) { + fstab->recs[cnt].fs_options = strdup(tmp_fs_options); + } else { + fstab->recs[cnt].fs_options = NULL; + } + + if (!(p = strtok_r(NULL, delim, &save_ptr))) { + ERROR("Error parsing fs_mgr_options\n"); + return 0; + } + fstab->recs[cnt].fs_mgr_flags = parse_flags(p, fs_mgr_flags, + &flag_vals, NULL, 0); + fstab->recs[cnt].key_loc = flag_vals.key_loc; + fstab->recs[cnt].length = flag_vals.part_length; + fstab->recs[cnt].label = flag_vals.label; + fstab->recs[cnt].partnum = flag_vals.partnum; + fstab->recs[cnt].swap_prio = flag_vals.swap_prio; + fstab->recs[cnt].zram_size = flag_vals.zram_size; + cnt++; + } + fclose(fstab_file); + + return fstab; +} + +void fs_mgr_free_fstab(struct fstab *fstab) +{ + int i; + + if (!fstab) { + return; + } + + for (i = 0; i < fstab->num_entries; i++) { + /* Free the pointers return by strdup(3) */ + free(fstab->recs[i].blk_device); + free(fstab->recs[i].mount_point); + free(fstab->recs[i].fs_type); + free(fstab->recs[i].fs_options); + free(fstab->recs[i].key_loc); + free(fstab->recs[i].label); + i++; + } + + /* Free the fstab_recs array created by calloc(3) */ + free(fstab->recs); + + /* Free the fstab filename */ + free(fstab->fstab_filename); + + /* Free fstab */ + free(fstab); +} + +static void check_fs(char *blk_device, char *fs_type, char *target) +{ + int status; + int ret; + long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID; + char *tmpmnt_opts = "nomblk_io_submit,errors=remount-ro"; + char *e2fsck_argv[] = { + E2FSCK_BIN, + "-y", + blk_device + }; + + /* Check for the types of filesystems we know how to check */ + if (!strcmp(fs_type, "ext2") || !strcmp(fs_type, "ext3") || !strcmp(fs_type, "ext4")) { + /* + * 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. + */ + ret = mount(blk_device, target, fs_type, tmpmnt_flags, tmpmnt_opts); + if (!ret) { + umount(target); + } + + INFO("Running %s on %s\n", E2FSCK_BIN, blk_device); + + ret = android_fork_execvp_ext(ARRAY_SIZE(e2fsck_argv), e2fsck_argv, + &status, true, LOG_KLOG | LOG_FILE, + true, FSCK_LOG_FILE); + + if (ret < 0) { + /* No need to check for error in fork, we can't really handle it now */ + ERROR("Failed trying to run %s\n", E2FSCK_BIN); + } + } + + return; +} + +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. + */ +static void fs_set_blk_ro(const char *blockdev) +{ + int fd; + int ON = 1; + + fd = open(blockdev, O_RDONLY); + if (fd < 0) { + // should never happen + return; + } + + ioctl(fd, BLKROSET, &ON); + close(fd); +} + +/* + * __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 char *filesystemtype, unsigned long mountflags, + const void *data) +{ + int ret = mount(source, target, filesystemtype, mountflags, data); + + if ((ret == 0) && (mountflags & MS_RDONLY) != 0) { + fs_set_blk_ro(source); + } + + return ret; +} + +static int fs_match(char *in1, 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; +} + +int fs_mgr_mount_all(struct fstab *fstab) +{ + int i = 0; + int encrypted = 0; + int ret = -1; + int mret; + + if (!fstab) { + return ret; + } + + for (i = 0; i < fstab->num_entries; i++) { + /* Don't mount entries that are managed by vold */ + if (fstab->recs[i].fs_mgr_flags & (MF_VOLDMANAGED | MF_RECOVERYONLY)) { + 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; + } + + if (fstab->recs[i].fs_mgr_flags & MF_WAIT) { + wait_for_file(fstab->recs[i].blk_device, WAIT_TIMEOUT); + } + + if (fstab->recs[i].fs_mgr_flags & MF_CHECK) { + check_fs(fstab->recs[i].blk_device, fstab->recs[i].fs_type, + fstab->recs[i].mount_point); + } + + if (fstab->recs[i].fs_mgr_flags & MF_VERIFY) { + if (fs_mgr_setup_verity(&fstab->recs[i]) < 0) { + ERROR("Could not set up verified partition, skipping!"); + continue; + } + } + + mret = __mount(fstab->recs[i].blk_device, fstab->recs[i].mount_point, + fstab->recs[i].fs_type, fstab->recs[i].flags, + fstab->recs[i].fs_options); + + if (!mret) { + /* Success! Go get the next one */ + continue; + } + + /* mount(2) returned an error, check if it's encrypted and deal with it */ + if ((fstab->recs[i].fs_mgr_flags & MF_CRYPT) && + !partition_wiped(fstab->recs[i].blk_device)) { + /* Need to mount a tmpfs at this mountpoint for now, and set + * properties that vold will query later for decrypting + */ + if (mount("tmpfs", fstab->recs[i].mount_point, "tmpfs", + MS_NOATIME | MS_NOSUID | MS_NODEV, CRYPTO_TMPFS_OPTIONS) < 0) { + ERROR("Cannot mount tmpfs filesystem for encrypted fs at %s\n", + fstab->recs[i].mount_point); + goto out; + } + encrypted = 1; + } else { + ERROR("Cannot mount filesystem on %s at %s\n", + fstab->recs[i].blk_device, fstab->recs[i].mount_point); + goto out; + } + } + + if (encrypted) { + ret = 1; + } else { + ret = 0; + } + +out: + 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 + */ +int fs_mgr_do_mount(struct fstab *fstab, char *n_name, char *n_blk_device, + char *tmp_mount_point) +{ + int i = 0; + int ret = -1; + char *m; + + if (!fstab) { + return ret; + } + + 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")) { + ERROR("Cannot mount filesystem of type %s on %s\n", + fstab->recs[i].fs_type, n_blk_device); + goto out; + } + + /* First check the filesystem if requested */ + if (fstab->recs[i].fs_mgr_flags & MF_WAIT) { + wait_for_file(n_blk_device, WAIT_TIMEOUT); + } + + if (fstab->recs[i].fs_mgr_flags & MF_CHECK) { + check_fs(n_blk_device, fstab->recs[i].fs_type, + fstab->recs[i].mount_point); + } + + if (fstab->recs[i].fs_mgr_flags & MF_VERIFY) { + if (fs_mgr_setup_verity(&fstab->recs[i]) < 0) { + ERROR("Could not set up verified partition, skipping!"); + continue; + } + } + + /* Now mount it where requested */ + if (tmp_mount_point) { + m = tmp_mount_point; + } else { + m = fstab->recs[i].mount_point; + } + if (__mount(n_blk_device, m, fstab->recs[i].fs_type, + fstab->recs[i].flags, fstab->recs[i].fs_options)) { + ERROR("Cannot mount filesystem on %s at %s\n", + n_blk_device, m); + goto out; + } else { + ret = 0; + goto out; + } + } + + /* We didn't find a match, say so and return an error */ + ERROR("Cannot find mount point %s in fstab\n", fstab->recs[i].mount_point); + +out: + return ret; +} + +/* + * mount a tmpfs filesystem at the given point. + * return 0 on success, non-zero on failure. + */ +int fs_mgr_do_tmpfs_mount(char *n_name) +{ + int ret; + + ret = mount("tmpfs", n_name, "tmpfs", + MS_NOATIME | MS_NOSUID | MS_NODEV, CRYPTO_TMPFS_OPTIONS); + if (ret < 0) { + ERROR("Cannot mount tmpfs filesystem at %s\n", 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)) { + ERROR("Cannot unmount filesystem at %s\n", 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; + char *mkswap_argv[2] = { + MKSWAP_BIN, + NULL + }; + + 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; + + zram_fp = fopen(ZRAM_CONF_DEV, "r+"); + if (zram_fp == NULL) { + ERROR("Unable to open zram conf device " ZRAM_CONF_DEV); + ret = -1; + continue; + } + fprintf(zram_fp, "%d\n", fstab->recs[i].zram_size); + fclose(zram_fp); + } + + if (fstab->recs[i].fs_mgr_flags & MF_WAIT) { + wait_for_file(fstab->recs[i].blk_device, WAIT_TIMEOUT); + } + + /* Initialize the swap area */ + mkswap_argv[1] = fstab->recs[i].blk_device; + err = android_fork_execvp_ext(ARRAY_SIZE(mkswap_argv), mkswap_argv, + &status, true, LOG_KLOG, false, NULL); + if (err) { + ERROR("mkswap failed for %s\n", 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; + } + // requires sys/swap.h which is not available in older trees + // this entire function does not appear to be used for decrypt + err = -1; //swapon(fstab->recs[i].blk_device, flags); + if (err) { + ERROR("swapon failed for %s\n", fstab->recs[i].blk_device); + ret = -1; + } + } + + return ret; +} + +/* + * key_loc must be at least PROPERTY_VALUE_MAX bytes long + * + * real_blk_device must be at least PROPERTY_VALUE_MAX bytes long + */ +int fs_mgr_get_crypt_info(struct fstab *fstab, char *key_loc, char *real_blk_device, int size) +{ + int i = 0; + + if (!fstab) { + return -1; + } + /* Initialize return values to null strings */ + if (key_loc) { + *key_loc = '\0'; + } + if (real_blk_device) { + *real_blk_device = '\0'; + } + + /* 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) { + continue; + } + if (!(fstab->recs[i].fs_mgr_flags & MF_CRYPT)) { + continue; + } + + /* We found a match */ + if (key_loc) { + strlcpy(key_loc, fstab->recs[i].key_loc, size); + } + if (real_blk_device) { + strlcpy(real_blk_device, fstab->recs[i].blk_device, size); + } + break; + } + + return 0; +} + +/* Add an entry to the fstab, and return 0 on success or -1 on error */ +int fs_mgr_add_entry(struct fstab *fstab, + const char *mount_point, const char *fs_type, + const char *blk_device, long long length) +{ + struct fstab_rec *new_fstab_recs; + int n = fstab->num_entries; + + new_fstab_recs = (struct fstab_rec *) + realloc(fstab->recs, sizeof(struct fstab_rec) * (n + 1)); + + if (!new_fstab_recs) { + return -1; + } + + /* A new entry was added, so initialize it */ + memset(&new_fstab_recs[n], 0, sizeof(struct fstab_rec)); + new_fstab_recs[n].mount_point = strdup(mount_point); + new_fstab_recs[n].fs_type = strdup(fs_type); + new_fstab_recs[n].blk_device = strdup(blk_device); + new_fstab_recs[n].length = 0; + + /* Update the fstab struct */ + fstab->recs = new_fstab_recs; + fstab->num_entries++; + + return 0; +} + +struct fstab_rec *fs_mgr_get_entry_for_mount_point(struct fstab *fstab, const char *path) +{ + int i; + + if (!fstab) { + return NULL; + } + + for (i = 0; i < fstab->num_entries; i++) { + int len = strlen(fstab->recs[i].mount_point); + if (strncmp(path, fstab->recs[i].mount_point, len) == 0 && + (path[len] == '\0' || path[len] == '/')) { + return &fstab->recs[i]; + } + } + + return NULL; +} + +int fs_mgr_is_voldmanaged(struct fstab_rec *fstab) +{ + return fstab->fs_mgr_flags & MF_VOLDMANAGED; +} + +int fs_mgr_is_nonremovable(struct fstab_rec *fstab) +{ + return fstab->fs_mgr_flags & MF_NONREMOVABLE; +} + +int fs_mgr_is_encryptable(struct fstab_rec *fstab) +{ + return fstab->fs_mgr_flags & MF_CRYPT; +} + +int fs_mgr_is_noemulatedsd(struct fstab_rec *fstab) +{ + return fstab->fs_mgr_flags & MF_NOEMULATEDSD; +} |