TWRP-ify AOSP code
Pull in most TWRP sources
Stub out partition management code
Make it compile -- probably will not boot
Kind of a mess but have to start somewhere
diff --git a/crypto/ics/cryptfs.c b/crypto/ics/cryptfs.c
new file mode 100644
index 0000000..0540366
--- /dev/null
+++ b/crypto/ics/cryptfs.c
@@ -0,0 +1,1164 @@
+/*
+ * Copyright (C) 2010 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.
+ */
+
+/* TO DO:
+ * 1. Perhaps keep several copies of the encrypted key, in case something
+ * goes horribly wrong?
+ *
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <linux/dm-ioctl.h>
+#include <libgen.h>
+#include <stdlib.h>
+#include <sys/param.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <openssl/evp.h>
+#include <openssl/sha.h>
+#include <errno.h>
+#include <cutils/android_reboot.h>
+#include <ext4.h>
+#include <linux/kdev_t.h>
+#include "cryptfs.h"
+#define LOG_TAG "Cryptfs"
+#include "cutils/log.h"
+#include "cutils/properties.h"
+#include "hardware_legacy/power.h"
+//#include "VolumeManager.h"
+
+#define DM_CRYPT_BUF_SIZE 4096
+#define DATA_MNT_POINT "/data"
+
+#define HASH_COUNT 2000
+#define KEY_LEN_BYTES 16
+#define IV_LEN_BYTES 16
+
+#define KEY_LOC_PROP "ro.crypto.keyfile.userdata"
+#define KEY_IN_FOOTER "footer"
+
+#define EXT4_FS 1
+#define FAT_FS 2
+
+char *me = "cryptfs";
+
+static unsigned char saved_master_key[KEY_LEN_BYTES];
+static char *saved_data_blkdev;
+static char *saved_mount_point;
+static int master_key_saved = 0;
+
+static void ioctl_init(struct dm_ioctl *io, size_t dataSize, const char *name, unsigned flags)
+{
+ memset(io, 0, dataSize);
+ io->data_size = dataSize;
+ io->data_start = sizeof(struct dm_ioctl);
+ io->version[0] = 4;
+ io->version[1] = 0;
+ io->version[2] = 0;
+ io->flags = flags;
+ if (name) {
+ strncpy(io->name, name, sizeof(io->name));
+ }
+}
+
+static unsigned int get_fs_size(char *dev)
+{
+ int fd, block_size;
+ struct ext4_super_block sb;
+ off64_t len;
+
+ if ((fd = open(dev, O_RDONLY)) < 0) {
+ SLOGE("Cannot open device to get filesystem size ");
+ return 0;
+ }
+
+ if (lseek64(fd, 1024, SEEK_SET) < 0) {
+ SLOGE("Cannot seek to superblock");
+ return 0;
+ }
+
+ if (read(fd, &sb, sizeof(sb)) != sizeof(sb)) {
+ SLOGE("Cannot read superblock");
+ return 0;
+ }
+
+ close(fd);
+
+ block_size = 1024 << sb.s_log_block_size;
+ /* compute length in bytes */
+ len = ( ((off64_t)sb.s_blocks_count_hi << 32) + sb.s_blocks_count_lo) * block_size;
+
+ /* return length in sectors */
+ return (unsigned int) (len / 512);
+}
+
+static unsigned int get_blkdev_size(int fd)
+{
+ unsigned int nr_sec;
+
+ if ( (ioctl(fd, BLKGETSIZE, &nr_sec)) == -1) {
+ nr_sec = 0;
+ }
+
+ return nr_sec;
+}
+
+/* key or salt can be NULL, in which case just skip writing that value. Useful to
+ * update the failed mount count but not change the key.
+ */
+static int put_crypt_ftr_and_key(char *real_blk_name, struct crypt_mnt_ftr *crypt_ftr,
+ unsigned char *key, unsigned char *salt)
+{
+ int fd;
+ unsigned int nr_sec, cnt;
+ off64_t off;
+ int rc = -1;
+ char *fname;
+ char key_loc[PROPERTY_VALUE_MAX];
+ struct stat statbuf;
+
+ property_get(KEY_LOC_PROP, key_loc, KEY_IN_FOOTER);
+
+ if (!strcmp(key_loc, KEY_IN_FOOTER)) {
+ fname = real_blk_name;
+ if ( (fd = open(fname, O_RDWR)) < 0) {
+ SLOGE("Cannot open real block device %s\n", fname);
+ return -1;
+ }
+
+ if ( (nr_sec = get_blkdev_size(fd)) == 0) {
+ SLOGE("Cannot get size of block device %s\n", fname);
+ goto errout;
+ }
+
+ /* If it's an encrypted Android partition, the last 16 Kbytes contain the
+ * encryption info footer and key, and plenty of bytes to spare for future
+ * growth.
+ */
+ off = ((off64_t)nr_sec * 512) - CRYPT_FOOTER_OFFSET;
+
+ if (lseek64(fd, off, SEEK_SET) == -1) {
+ SLOGE("Cannot seek to real block device footer\n");
+ goto errout;
+ }
+ } else if (key_loc[0] == '/') {
+ fname = key_loc;
+ if ( (fd = open(fname, O_RDWR | O_CREAT, 0600)) < 0) {
+ SLOGE("Cannot open footer file %s\n", fname);
+ return -1;
+ }
+ } else {
+ SLOGE("Unexpected value for" KEY_LOC_PROP "\n");
+ return -1;;
+ }
+
+ if ((cnt = write(fd, crypt_ftr, sizeof(struct crypt_mnt_ftr))) != sizeof(struct crypt_mnt_ftr)) {
+ SLOGE("Cannot write real block device footer\n");
+ goto errout;
+ }
+
+ if (key) {
+ if (crypt_ftr->keysize != KEY_LEN_BYTES) {
+ SLOGE("Keysize of %d bits not supported for real block device %s\n",
+ crypt_ftr->keysize*8, fname);
+ goto errout;
+ }
+
+ if ( (cnt = write(fd, key, crypt_ftr->keysize)) != crypt_ftr->keysize) {
+ SLOGE("Cannot write key for real block device %s\n", fname);
+ goto errout;
+ }
+ }
+
+ if (salt) {
+ /* Compute the offset from the last write to the salt */
+ off = KEY_TO_SALT_PADDING;
+ if (! key)
+ off += crypt_ftr->keysize;
+
+ if (lseek64(fd, off, SEEK_CUR) == -1) {
+ SLOGE("Cannot seek to real block device salt \n");
+ goto errout;
+ }
+
+ if ( (cnt = write(fd, salt, SALT_LEN)) != SALT_LEN) {
+ SLOGE("Cannot write salt for real block device %s\n", fname);
+ goto errout;
+ }
+ }
+
+ fstat(fd, &statbuf);
+ /* If the keys are kept on a raw block device, do not try to truncate it. */
+ if (S_ISREG(statbuf.st_mode) && (key_loc[0] == '/')) {
+ if (ftruncate(fd, 0x4000)) {
+ SLOGE("Cannot set footer file size\n", fname);
+ goto errout;
+ }
+ }
+
+ /* Success! */
+ rc = 0;
+
+errout:
+ close(fd);
+ return rc;
+
+}
+
+static int get_crypt_ftr_and_key(char *real_blk_name, struct crypt_mnt_ftr *crypt_ftr,
+ unsigned char *key, unsigned char *salt)
+{
+ int fd;
+ unsigned int nr_sec, cnt;
+ off64_t off;
+ int rc = -1;
+ char key_loc[PROPERTY_VALUE_MAX];
+ char *fname;
+ struct stat statbuf;
+
+ property_get(KEY_LOC_PROP, key_loc, KEY_IN_FOOTER);
+
+ if (!strcmp(key_loc, KEY_IN_FOOTER)) {
+ fname = real_blk_name;
+ if ( (fd = open(fname, O_RDONLY)) < 0) {
+ ui_print("Cannot open real block device %s\n", fname);
+ return -1;
+ }
+
+ if ( (nr_sec = get_blkdev_size(fd)) == 0) {
+ SLOGE("Cannot get size of block device %s\n", fname);
+ goto errout;
+ }
+
+ /* If it's an encrypted Android partition, the last 16 Kbytes contain the
+ * encryption info footer and key, and plenty of bytes to spare for future
+ * growth.
+ */
+ off = ((off64_t)nr_sec * 512) - CRYPT_FOOTER_OFFSET;
+
+ if (lseek64(fd, off, SEEK_SET) == -1) {
+ ui_print("Cannot seek to real block device footer\n");
+ goto errout;
+ }
+ } else if (key_loc[0] == '/') {
+ fname = key_loc;
+ if ( (fd = open(fname, O_RDONLY)) < 0) {
+ ui_print("Cannot open footer file %s\n", fname);
+ return -1;
+ }
+
+ /* Make sure it's 16 Kbytes in length */
+ fstat(fd, &statbuf);
+ if (S_ISREG(statbuf.st_mode) && (statbuf.st_size != 0x4000)) {
+ ui_print("footer file %s is not the expected size!\n", fname);
+ goto errout;
+ }
+ } else {
+ ui_print("Unexpected value for" KEY_LOC_PROP "\n");
+ return -1;;
+ }
+
+ if ( (cnt = read(fd, crypt_ftr, sizeof(struct crypt_mnt_ftr))) != sizeof(struct crypt_mnt_ftr)) {
+ ui_print("Cannot read real block device footer\n");
+ goto errout;
+ }
+
+ if (crypt_ftr->magic != CRYPT_MNT_MAGIC) {
+ ui_print("Bad magic for real block device %s\n", fname);
+ goto errout;
+ }
+
+ if (crypt_ftr->major_version != 1) {
+ ui_print("Cannot understand major version %d real block device footer\n",
+ crypt_ftr->major_version);
+ goto errout;
+ }
+
+ if (crypt_ftr->minor_version != 0) {
+ ui_print("Warning: crypto footer minor version %d, expected 0, continuing...\n",
+ crypt_ftr->minor_version);
+ }
+
+ if (crypt_ftr->ftr_size > sizeof(struct crypt_mnt_ftr)) {
+ /* the footer size is bigger than we expected.
+ * Skip to it's stated end so we can read the key.
+ */
+ if (lseek(fd, crypt_ftr->ftr_size - sizeof(struct crypt_mnt_ftr), SEEK_CUR) == -1) {
+ ui_print("Cannot seek to start of key\n");
+ goto errout;
+ }
+ }
+
+ if (crypt_ftr->keysize != KEY_LEN_BYTES) {
+ ui_print("Keysize of %d bits not supported for real block device %s\n",
+ crypt_ftr->keysize * 8, fname);
+ goto errout;
+ }
+
+ if ( (cnt = read(fd, key, crypt_ftr->keysize)) != crypt_ftr->keysize) {
+ ui_print("Cannot read key for real block device %s\n", fname);
+ goto errout;
+ }
+
+ if (lseek64(fd, KEY_TO_SALT_PADDING, SEEK_CUR) == -1) {
+ ui_print("Cannot seek to real block device salt\n");
+ goto errout;
+ }
+
+ if ( (cnt = read(fd, salt, SALT_LEN)) != SALT_LEN) {
+ ui_print("Cannot read salt for real block device %s\n", fname);
+ goto errout;
+ }
+
+ /* Success! */
+ rc = 0;
+
+errout:
+ close(fd);
+ return rc;
+}
+
+/* Convert a binary key of specified length into an ascii hex string equivalent,
+ * without the leading 0x and with null termination
+ */
+void convert_key_to_hex_ascii(unsigned char *master_key, unsigned int keysize,
+ char *master_key_ascii)
+{
+ unsigned int i, a;
+ unsigned char nibble;
+
+ for (i=0, a=0; i<keysize; i++, a+=2) {
+ /* For each byte, write out two ascii hex digits */
+ nibble = (master_key[i] >> 4) & 0xf;
+ master_key_ascii[a] = nibble + (nibble > 9 ? 0x37 : 0x30);
+
+ nibble = master_key[i] & 0xf;
+ master_key_ascii[a+1] = nibble + (nibble > 9 ? 0x37 : 0x30);
+ }
+
+ /* Add the null termination */
+ master_key_ascii[a] = '\0';
+
+}
+
+static int create_crypto_blk_dev(struct crypt_mnt_ftr *crypt_ftr, unsigned char *master_key,
+ char *real_blk_name, char *crypto_blk_name, const char *name)
+{
+ char buffer[DM_CRYPT_BUF_SIZE];
+ char master_key_ascii[129]; /* Large enough to hold 512 bit key and null */
+ char *crypt_params;
+ struct dm_ioctl *io;
+ struct dm_target_spec *tgt;
+ unsigned int minor;
+ int fd;
+ int retval = -1;
+
+ if ((fd = open("/dev/device-mapper", O_RDWR)) < 0 ) {
+ ui_print("Cannot open device-mapper\n");
+ goto errout;
+ }
+
+ io = (struct dm_ioctl *) buffer;
+
+ ioctl_init(io, DM_CRYPT_BUF_SIZE, name, 0);
+ if (ioctl(fd, DM_DEV_CREATE, io)) {
+ ui_print("Cannot create dm-crypt device\n");
+ goto errout;
+ }
+
+ /* Get the device status, in particular, the name of it's device file */
+ ioctl_init(io, DM_CRYPT_BUF_SIZE, name, 0);
+ if (ioctl(fd, DM_DEV_STATUS, io)) {
+ ui_print("Cannot retrieve dm-crypt device status\n");
+ goto errout;
+ }
+ minor = (io->dev & 0xff) | ((io->dev >> 12) & 0xfff00);
+ snprintf(crypto_blk_name, MAXPATHLEN, "/dev/block/dm-%u", minor);
+
+ /* Load the mapping table for this device */
+ tgt = (struct dm_target_spec *) &buffer[sizeof(struct dm_ioctl)];
+
+ ioctl_init(io, 4096, name, 0);
+ io->target_count = 1;
+ tgt->status = 0;
+ tgt->sector_start = 0;
+ tgt->length = crypt_ftr->fs_size;
+ strcpy(tgt->target_type, "crypt");
+
+ crypt_params = buffer + sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec);
+ convert_key_to_hex_ascii(master_key, crypt_ftr->keysize, master_key_ascii);
+ sprintf(crypt_params, "%s %s 0 %s 0", crypt_ftr->crypto_type_name,
+ master_key_ascii, real_blk_name);
+ crypt_params += strlen(crypt_params) + 1;
+ crypt_params = (char *) (((unsigned long)crypt_params + 7) & ~8); /* Align to an 8 byte boundary */
+ tgt->next = crypt_params - buffer;
+
+ if (ioctl(fd, DM_TABLE_LOAD, io)) {
+ ui_print("Cannot load dm-crypt mapping table.\n");
+ goto errout;
+ }
+
+ /* Resume this device to activate it */
+ ioctl_init(io, 4096, name, 0);
+
+ if (ioctl(fd, DM_DEV_SUSPEND, io)) {
+ ui_print("Cannot resume the dm-crypt device\n");
+ goto errout;
+ }
+
+ /* We made it here with no errors. Woot! */
+ retval = 0;
+
+errout:
+ close(fd); /* If fd is <0 from a failed open call, it's safe to just ignore the close error */
+
+ return retval;
+}
+
+static int delete_crypto_blk_dev(char *name)
+{
+ int fd;
+ char buffer[DM_CRYPT_BUF_SIZE];
+ struct dm_ioctl *io;
+ int retval = -1;
+
+ if ((fd = open("/dev/device-mapper", O_RDWR)) < 0 ) {
+ ui_print("Cannot open device-mapper\n");
+ goto errout;
+ }
+
+ io = (struct dm_ioctl *) buffer;
+
+ ioctl_init(io, DM_CRYPT_BUF_SIZE, name, 0);
+ if (ioctl(fd, DM_DEV_REMOVE, io)) {
+ ui_print("Cannot remove dm-crypt device\n");
+ goto errout;
+ }
+
+ /* We made it here with no errors. Woot! */
+ retval = 0;
+
+errout:
+ close(fd); /* If fd is <0 from a failed open call, it's safe to just ignore the close error */
+
+ return retval;
+
+}
+
+static void pbkdf2(char *passwd, unsigned char *salt, unsigned char *ikey)
+{
+ /* Turn the password into a key and IV that can decrypt the master key */
+ PKCS5_PBKDF2_HMAC_SHA1(passwd, strlen(passwd), salt, SALT_LEN,
+ HASH_COUNT, KEY_LEN_BYTES+IV_LEN_BYTES, ikey);
+}
+
+static int encrypt_master_key(char *passwd, unsigned char *salt,
+ unsigned char *decrypted_master_key,
+ unsigned char *encrypted_master_key)
+{
+ unsigned char ikey[32+32] = { 0 }; /* Big enough to hold a 256 bit key and 256 bit IV */
+ EVP_CIPHER_CTX e_ctx;
+ int encrypted_len, final_len;
+
+ /* Turn the password into a key and IV that can decrypt the master key */
+ pbkdf2(passwd, salt, ikey);
+
+ /* Initialize the decryption engine */
+ if (! EVP_EncryptInit(&e_ctx, EVP_aes_128_cbc(), ikey, ikey+KEY_LEN_BYTES)) {
+ SLOGE("EVP_EncryptInit failed\n");
+ return -1;
+ }
+ EVP_CIPHER_CTX_set_padding(&e_ctx, 0); /* Turn off padding as our data is block aligned */
+
+ /* Encrypt the master key */
+ if (! EVP_EncryptUpdate(&e_ctx, encrypted_master_key, &encrypted_len,
+ decrypted_master_key, KEY_LEN_BYTES)) {
+ SLOGE("EVP_EncryptUpdate failed\n");
+ return -1;
+ }
+ if (! EVP_EncryptFinal(&e_ctx, encrypted_master_key + encrypted_len, &final_len)) {
+ SLOGE("EVP_EncryptFinal failed\n");
+ return -1;
+ }
+
+ if (encrypted_len + final_len != KEY_LEN_BYTES) {
+ SLOGE("EVP_Encryption length check failed with %d, %d bytes\n", encrypted_len, final_len);
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+static int decrypt_master_key(char *passwd, unsigned char *salt,
+ unsigned char *encrypted_master_key,
+ unsigned char *decrypted_master_key)
+{
+ unsigned char ikey[32+32] = { 0 }; /* Big enough to hold a 256 bit key and 256 bit IV */
+ EVP_CIPHER_CTX d_ctx;
+ int decrypted_len, final_len;
+
+ /* Turn the password into a key and IV that can decrypt the master key */
+ pbkdf2(passwd, salt, ikey);
+
+ /* Initialize the decryption engine */
+ if (! EVP_DecryptInit(&d_ctx, EVP_aes_128_cbc(), ikey, ikey+KEY_LEN_BYTES)) {
+ return -1;
+ }
+ EVP_CIPHER_CTX_set_padding(&d_ctx, 0); /* Turn off padding as our data is block aligned */
+ /* Decrypt the master key */
+ if (! EVP_DecryptUpdate(&d_ctx, decrypted_master_key, &decrypted_len,
+ encrypted_master_key, KEY_LEN_BYTES)) {
+ return -1;
+ }
+ if (! EVP_DecryptFinal(&d_ctx, decrypted_master_key + decrypted_len, &final_len)) {
+ return -1;
+ }
+
+ if (decrypted_len + final_len != KEY_LEN_BYTES) {
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+static int create_encrypted_random_key(char *passwd, unsigned char *master_key, unsigned char *salt)
+{
+ int fd;
+ unsigned char key_buf[KEY_LEN_BYTES];
+ EVP_CIPHER_CTX e_ctx;
+ int encrypted_len, final_len;
+
+ /* Get some random bits for a key */
+ fd = open("/dev/urandom", O_RDONLY);
+ read(fd, key_buf, sizeof(key_buf));
+ read(fd, salt, SALT_LEN);
+ close(fd);
+
+ /* Now encrypt it with the password */
+ return encrypt_master_key(passwd, salt, key_buf, master_key);
+}
+
+static int get_orig_mount_parms(char *mount_point, char *fs_type, char *real_blkdev,
+ unsigned long *mnt_flags, char *fs_options)
+{
+ char mount_point2[PROPERTY_VALUE_MAX];
+ char fs_flags[PROPERTY_VALUE_MAX];
+
+ property_get("ro.crypto.fs_type", fs_type, "");
+ property_get("ro.crypto.fs_real_blkdev", real_blkdev, "");
+ property_get("ro.crypto.fs_mnt_point", mount_point2, "");
+ property_get("ro.crypto.fs_options", fs_options, "");
+ property_get("ro.crypto.fs_flags", fs_flags, "");
+ *mnt_flags = strtol(fs_flags, 0, 0);
+
+ if (strcmp(mount_point, mount_point2)) {
+ /* Consistency check. These should match. If not, something odd happened. */
+ return -1;
+ }
+
+ return 0;
+}
+
+static int wait_and_unmount(char *mountpoint)
+{
+ int i, rc;
+#define WAIT_UNMOUNT_COUNT 20
+
+ /* Now umount the tmpfs filesystem */
+ for (i=0; i<WAIT_UNMOUNT_COUNT; i++) {
+ if (umount(mountpoint)) {
+ if (errno == EINVAL) {
+ /* EINVAL is returned if the directory is not a mountpoint,
+ * i.e. there is no filesystem mounted there. So just get out.
+ */
+ break;
+ }
+ sleep(1);
+ i++;
+ } else {
+ break;
+ }
+ }
+
+ if (i < WAIT_UNMOUNT_COUNT) {
+ SLOGD("unmounting %s succeeded\n", mountpoint);
+ rc = 0;
+ } else {
+ SLOGE("unmounting %s failed\n", mountpoint);
+ rc = -1;
+ }
+
+ return rc;
+}
+
+#define DATA_PREP_TIMEOUT 100
+static int prep_data_fs(void)
+{
+ int i;
+
+ /* Do the prep of the /data filesystem */
+ property_set("vold.post_fs_data_done", "0");
+ property_set("vold.decrypt", "trigger_post_fs_data");
+ SLOGD("Just triggered post_fs_data\n");
+
+ /* Wait a max of 25 seconds, hopefully it takes much less */
+ for (i=0; i<DATA_PREP_TIMEOUT; i++) {
+ char p[PROPERTY_VALUE_MAX];
+
+ property_get("vold.post_fs_data_done", p, "0");
+ if (*p == '1') {
+ break;
+ } else {
+ usleep(250000);
+ }
+ }
+ if (i == DATA_PREP_TIMEOUT) {
+ /* Ugh, we failed to prep /data in time. Bail. */
+ return -1;
+ } else {
+ SLOGD("post_fs_data done\n");
+ return 0;
+ }
+}
+
+int cryptfs_restart(void)
+{
+ char fs_type[32];
+ char real_blkdev[MAXPATHLEN];
+ char crypto_blkdev[MAXPATHLEN];
+ char fs_options[256];
+ unsigned long mnt_flags;
+ struct stat statbuf;
+ int rc = -1, i;
+ static int restart_successful = 0;
+
+ /* Validate that it's OK to call this routine */
+ if (! master_key_saved) {
+ SLOGE("Encrypted filesystem not validated, aborting");
+ return -1;
+ }
+
+ if (restart_successful) {
+ SLOGE("System already restarted with encrypted disk, aborting");
+ return -1;
+ }
+
+ /* Here is where we shut down the framework. The init scripts
+ * start all services in one of three classes: core, main or late_start.
+ * On boot, we start core and main. Now, we stop main, but not core,
+ * as core includes vold and a few other really important things that
+ * we need to keep running. Once main has stopped, we should be able
+ * to umount the tmpfs /data, then mount the encrypted /data.
+ * We then restart the class main, and also the class late_start.
+ * At the moment, I've only put a few things in late_start that I know
+ * are not needed to bring up the framework, and that also cause problems
+ * with unmounting the tmpfs /data, but I hope to add add more services
+ * to the late_start class as we optimize this to decrease the delay
+ * till the user is asked for the password to the filesystem.
+ */
+
+ /* The init files are setup to stop the class main when vold.decrypt is
+ * set to trigger_reset_main.
+ */
+ property_set("vold.decrypt", "trigger_reset_main");
+ SLOGD("Just asked init to shut down class main\n");
+
+ /* Now that the framework is shutdown, we should be able to umount()
+ * the tmpfs filesystem, and mount the real one.
+ */
+
+ property_get("ro.crypto.fs_crypto_blkdev", crypto_blkdev, "");
+ if (strlen(crypto_blkdev) == 0) {
+ SLOGE("fs_crypto_blkdev not set\n");
+ return -1;
+ }
+
+ if (! get_orig_mount_parms(DATA_MNT_POINT, fs_type, real_blkdev, &mnt_flags, fs_options)) {
+ SLOGD("Just got orig mount parms\n");
+
+ if (! (rc = wait_and_unmount(DATA_MNT_POINT)) ) {
+ /* If that succeeded, then mount the decrypted filesystem */
+ mount(crypto_blkdev, DATA_MNT_POINT, fs_type, mnt_flags, fs_options);
+
+ property_set("vold.decrypt", "trigger_load_persist_props");
+ /* Create necessary paths on /data */
+ if (prep_data_fs()) {
+ return -1;
+ }
+
+ /* startup service classes main and late_start */
+ property_set("vold.decrypt", "trigger_restart_framework");
+ SLOGD("Just triggered restart_framework\n");
+
+ /* Give it a few moments to get started */
+ sleep(1);
+ }
+ }
+
+ if (rc == 0) {
+ restart_successful = 1;
+ }
+
+ return rc;
+}
+
+static int do_crypto_complete(char *mount_point)
+{
+ struct crypt_mnt_ftr crypt_ftr;
+ unsigned char encrypted_master_key[32];
+ unsigned char salt[SALT_LEN];
+ char real_blkdev[MAXPATHLEN];
+ char fs_type[PROPERTY_VALUE_MAX];
+ char fs_options[PROPERTY_VALUE_MAX];
+ unsigned long mnt_flags;
+ char encrypted_state[PROPERTY_VALUE_MAX];
+
+ property_get("ro.crypto.state", encrypted_state, "");
+ if (strcmp(encrypted_state, "encrypted") ) {
+ SLOGE("not running with encryption, aborting");
+ return 1;
+ }
+
+ if (get_orig_mount_parms(mount_point, fs_type, real_blkdev, &mnt_flags, fs_options)) {
+ SLOGE("Error reading original mount parms for mount point %s\n", mount_point);
+ return -1;
+ }
+
+ if (get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt)) {
+ SLOGE("Error getting crypt footer and key\n");
+ return -1;
+ }
+
+ if (crypt_ftr.flags & CRYPT_ENCRYPTION_IN_PROGRESS) {
+ SLOGE("Encryption process didn't finish successfully\n");
+ return -2; /* -2 is the clue to the UI that there is no usable data on the disk,
+ * and give the user an option to wipe the disk */
+ }
+
+ /* We passed the test! We shall diminish, and return to the west */
+ return 0;
+}
+
+static int test_mount_encrypted_fs(char *passwd, char *mount_point, char *label)
+{
+ struct crypt_mnt_ftr crypt_ftr;
+ /* Allocate enough space for a 256 bit key, but we may use less */
+ unsigned char encrypted_master_key[32], decrypted_master_key[32];
+ unsigned char salt[SALT_LEN];
+ char crypto_blkdev[MAXPATHLEN];
+ char real_blkdev[MAXPATHLEN];
+ char fs_type[PROPERTY_VALUE_MAX];
+ char fs_options[PROPERTY_VALUE_MAX];
+ char tmp_mount_point[64];
+ unsigned long mnt_flags;
+ unsigned int orig_failed_decrypt_count;
+ char encrypted_state[PROPERTY_VALUE_MAX];
+ int rc;
+
+ property_get("ro.crypto.state", encrypted_state, "");
+ if ( master_key_saved || strcmp(encrypted_state, "encrypted") ) {
+ ui_print("encrypted fs already validated or not running with encryption, aborting");
+ return -1;
+ }
+
+ if (get_orig_mount_parms(mount_point, fs_type, real_blkdev, &mnt_flags, fs_options)) {
+ ui_print("Error reading original mount parms for mount point %s\n", mount_point);
+ return -1;
+ }
+
+ if (get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt)) {
+ ui_print("Error getting crypt footer and key\n");
+ return -1;
+ }
+
+ ui_print("crypt_ftr->fs_size = %lld\n", crypt_ftr.fs_size);
+ orig_failed_decrypt_count = crypt_ftr.failed_decrypt_count;
+
+ if (! (crypt_ftr.flags & CRYPT_MNT_KEY_UNENCRYPTED) ) {
+ decrypt_master_key(passwd, salt, encrypted_master_key, decrypted_master_key);
+ }
+
+ if (create_crypto_blk_dev(&crypt_ftr, decrypted_master_key,
+ real_blkdev, crypto_blkdev, label)) {
+ ui_print("Error creating decrypted block device\n");
+ return -1;
+ }
+
+ /* If init detects an encrypted filesystme, it writes a file for each such
+ * encrypted fs into the tmpfs /data filesystem, and then the framework finds those
+ * files and passes that data to me */
+ /* Create a tmp mount point to try mounting the decryptd fs
+ * Since we're here, the mount_point should be a tmpfs filesystem, so make
+ * a directory in it to test mount the decrypted filesystem.
+ */
+ sprintf(tmp_mount_point, "%s/tmp_mnt", mount_point);
+ mkdir(tmp_mount_point, 0755);
+ if ( mount(crypto_blkdev, tmp_mount_point, "ext4", MS_RDONLY, "") ) {
+ ui_print("Error temp mounting decrypted block device\n");
+ delete_crypto_blk_dev(label);
+ crypt_ftr.failed_decrypt_count++;
+ } else {
+ /* Success, so just umount and we'll mount it properly when we restart
+ * the framework.
+ */
+ umount(tmp_mount_point);
+ crypt_ftr.failed_decrypt_count = 0;
+ }
+
+ if (orig_failed_decrypt_count != crypt_ftr.failed_decrypt_count) {
+ put_crypt_ftr_and_key(real_blkdev, &crypt_ftr, 0, 0);
+ }
+
+ if (crypt_ftr.failed_decrypt_count) {
+ /* We failed to mount the device, so return an error */
+ rc = crypt_ftr.failed_decrypt_count;
+
+ } else {
+ /* Woot! Success! Save the name of the crypto block device
+ * so we can mount it when restarting the framework.
+ */
+ property_set("ro.crypto.fs_crypto_blkdev", crypto_blkdev);
+
+ /* Also save a the master key so we can reencrypted the key
+ * the key when we want to change the password on it.
+ */
+ memcpy(saved_master_key, decrypted_master_key, KEY_LEN_BYTES);
+ saved_data_blkdev = strdup(real_blkdev);
+ saved_mount_point = strdup(mount_point);
+ master_key_saved = 1;
+ rc = 0;
+ }
+
+ return rc;
+}
+
+/* Called by vold when it wants to undo the crypto mapping of a volume it
+ * manages. This is usually in response to a factory reset, when we want
+ * to undo the crypto mapping so the volume is formatted in the clear.
+ */
+int cryptfs_revert_volume(const char *label)
+{
+ return delete_crypto_blk_dev((char *)label);
+}
+
+/*
+ * Called by vold when it's asked to mount an encrypted, nonremovable volume.
+ * Setup a dm-crypt mapping, use the saved master key from
+ * setting up the /data mapping, and return the new device path.
+ */
+int cryptfs_setup_volume(const char *label, int major, int minor,
+ char *crypto_sys_path, unsigned int max_path,
+ int *new_major, int *new_minor)
+{
+ char real_blkdev[MAXPATHLEN], crypto_blkdev[MAXPATHLEN];
+ struct crypt_mnt_ftr sd_crypt_ftr;
+ unsigned char key[32], salt[32];
+ struct stat statbuf;
+ int nr_sec, fd;
+
+ sprintf(real_blkdev, "/dev/block/vold/%d:%d", major, minor);
+
+ /* Just want the footer, but gotta get it all */
+ get_crypt_ftr_and_key(saved_data_blkdev, &sd_crypt_ftr, key, salt);
+
+ /* Update the fs_size field to be the size of the volume */
+ fd = open(real_blkdev, O_RDONLY);
+ nr_sec = get_blkdev_size(fd);
+ close(fd);
+ if (nr_sec == 0) {
+ SLOGE("Cannot get size of volume %s\n", real_blkdev);
+ return -1;
+ }
+
+ sd_crypt_ftr.fs_size = nr_sec;
+ create_crypto_blk_dev(&sd_crypt_ftr, saved_master_key, real_blkdev,
+ crypto_blkdev, label);
+
+ stat(crypto_blkdev, &statbuf);
+ *new_major = MAJOR(statbuf.st_rdev);
+ *new_minor = MINOR(statbuf.st_rdev);
+
+ /* Create path to sys entry for this block device */
+ snprintf(crypto_sys_path, max_path, "/devices/virtual/block/%s", strrchr(crypto_blkdev, '/')+1);
+
+ return 0;
+}
+
+int cryptfs_crypto_complete(void)
+{
+ return do_crypto_complete("/data");
+}
+
+int cryptfs_check_passwd(char *passwd)
+{
+ int rc = -1;
+
+ rc = test_mount_encrypted_fs(passwd, DATA_MNT_POINT, "userdata");
+
+ return rc;
+}
+
+int cryptfs_verify_passwd(char *passwd)
+{
+ struct crypt_mnt_ftr crypt_ftr;
+ /* Allocate enough space for a 256 bit key, but we may use less */
+ unsigned char encrypted_master_key[32], decrypted_master_key[32];
+ unsigned char salt[SALT_LEN];
+ char real_blkdev[MAXPATHLEN];
+ char fs_type[PROPERTY_VALUE_MAX];
+ char fs_options[PROPERTY_VALUE_MAX];
+ unsigned long mnt_flags;
+ char encrypted_state[PROPERTY_VALUE_MAX];
+ int rc;
+
+ property_get("ro.crypto.state", encrypted_state, "");
+ if (strcmp(encrypted_state, "encrypted") ) {
+ SLOGE("device not encrypted, aborting");
+ return -2;
+ }
+
+ if (!master_key_saved) {
+ SLOGE("encrypted fs not yet mounted, aborting");
+ return -1;
+ }
+
+ if (!saved_mount_point) {
+ SLOGE("encrypted fs failed to save mount point, aborting");
+ return -1;
+ }
+
+ if (get_orig_mount_parms(saved_mount_point, fs_type, real_blkdev, &mnt_flags, fs_options)) {
+ SLOGE("Error reading original mount parms for mount point %s\n", saved_mount_point);
+ return -1;
+ }
+
+ if (get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt)) {
+ SLOGE("Error getting crypt footer and key\n");
+ return -1;
+ }
+
+ if (crypt_ftr.flags & CRYPT_MNT_KEY_UNENCRYPTED) {
+ /* If the device has no password, then just say the password is valid */
+ rc = 0;
+ } else {
+ decrypt_master_key(passwd, salt, encrypted_master_key, decrypted_master_key);
+ if (!memcmp(decrypted_master_key, saved_master_key, crypt_ftr.keysize)) {
+ /* They match, the password is correct */
+ rc = 0;
+ } else {
+ /* If incorrect, sleep for a bit to prevent dictionary attacks */
+ sleep(1);
+ rc = 1;
+ }
+ }
+
+ return rc;
+}
+
+/* Initialize a crypt_mnt_ftr structure. The keysize is
+ * defaulted to 16 bytes, and the filesystem size to 0.
+ * Presumably, at a minimum, the caller will update the
+ * filesystem size and crypto_type_name after calling this function.
+ */
+static void cryptfs_init_crypt_mnt_ftr(struct crypt_mnt_ftr *ftr)
+{
+ ftr->magic = CRYPT_MNT_MAGIC;
+ ftr->major_version = 1;
+ ftr->minor_version = 0;
+ ftr->ftr_size = sizeof(struct crypt_mnt_ftr);
+ ftr->flags = 0;
+ ftr->keysize = KEY_LEN_BYTES;
+ ftr->spare1 = 0;
+ ftr->fs_size = 0;
+ ftr->failed_decrypt_count = 0;
+ ftr->crypto_type_name[0] = '\0';
+}
+
+static int cryptfs_enable_wipe(char *crypto_blkdev, off64_t size, int type)
+{
+ char cmdline[256];
+ int rc = -1;
+
+ if (type == EXT4_FS) {
+ snprintf(cmdline, sizeof(cmdline), "/system/bin/make_ext4fs -a /data -l %lld %s",
+ size * 512, crypto_blkdev);
+ SLOGI("Making empty filesystem with command %s\n", cmdline);
+ } else if (type== FAT_FS) {
+ snprintf(cmdline, sizeof(cmdline), "/system/bin/newfs_msdos -F 32 -O android -c 8 -s %lld %s",
+ size, crypto_blkdev);
+ SLOGI("Making empty filesystem with command %s\n", cmdline);
+ } else {
+ SLOGE("cryptfs_enable_wipe(): unknown filesystem type %d\n", type);
+ return -1;
+ }
+
+ if (system(cmdline)) {
+ SLOGE("Error creating empty filesystem on %s\n", crypto_blkdev);
+ } else {
+ SLOGD("Successfully created empty filesystem on %s\n", crypto_blkdev);
+ rc = 0;
+ }
+
+ return rc;
+}
+
+static inline int unix_read(int fd, void* buff, int len)
+{
+ int ret;
+ do { ret = read(fd, buff, len); } while (ret < 0 && errno == EINTR);
+ return ret;
+}
+
+static inline int unix_write(int fd, const void* buff, int len)
+{
+ int ret;
+ do { ret = write(fd, buff, len); } while (ret < 0 && errno == EINTR);
+ return ret;
+}
+
+#define CRYPT_INPLACE_BUFSIZE 4096
+#define CRYPT_SECTORS_PER_BUFSIZE (CRYPT_INPLACE_BUFSIZE / 512)
+static int cryptfs_enable_inplace(char *crypto_blkdev, char *real_blkdev, off64_t size,
+ off64_t *size_already_done, off64_t tot_size)
+{
+ int realfd, cryptofd;
+ char *buf[CRYPT_INPLACE_BUFSIZE];
+ int rc = -1;
+ off64_t numblocks, i, remainder;
+ off64_t one_pct, cur_pct, new_pct;
+ off64_t blocks_already_done, tot_numblocks;
+
+ if ( (realfd = open(real_blkdev, O_RDONLY)) < 0) {
+ SLOGE("Error opening real_blkdev %s for inplace encrypt\n", real_blkdev);
+ return -1;
+ }
+
+ if ( (cryptofd = open(crypto_blkdev, O_WRONLY)) < 0) {
+ SLOGE("Error opening crypto_blkdev %s for inplace encrypt\n", crypto_blkdev);
+ close(realfd);
+ return -1;
+ }
+
+ /* This is pretty much a simple loop of reading 4K, and writing 4K.
+ * The size passed in is the number of 512 byte sectors in the filesystem.
+ * So compute the number of whole 4K blocks we should read/write,
+ * and the remainder.
+ */
+ numblocks = size / CRYPT_SECTORS_PER_BUFSIZE;
+ remainder = size % CRYPT_SECTORS_PER_BUFSIZE;
+ tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE;
+ blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE;
+
+ SLOGE("Encrypting filesystem in place...");
+
+ one_pct = tot_numblocks / 100;
+ cur_pct = 0;
+ /* process the majority of the filesystem in blocks */
+ for (i=0; i<numblocks; i++) {
+ new_pct = (i + blocks_already_done) / one_pct;
+ if (new_pct > cur_pct) {
+ char buf[8];
+
+ cur_pct = new_pct;
+ snprintf(buf, sizeof(buf), "%lld", cur_pct);
+ property_set("vold.encrypt_progress", buf);
+ }
+ if (unix_read(realfd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
+ SLOGE("Error reading real_blkdev %s for inplace encrypt\n", crypto_blkdev);
+ goto errout;
+ }
+ if (unix_write(cryptofd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) {
+ SLOGE("Error writing crypto_blkdev %s for inplace encrypt\n", crypto_blkdev);
+ goto errout;
+ }
+ }
+
+ /* Do any remaining sectors */
+ for (i=0; i<remainder; i++) {
+ if (unix_read(realfd, buf, 512) <= 0) {
+ SLOGE("Error reading rival sectors from real_blkdev %s for inplace encrypt\n", crypto_blkdev);
+ goto errout;
+ }
+ if (unix_write(cryptofd, buf, 512) <= 0) {
+ SLOGE("Error writing final sectors to crypto_blkdev %s for inplace encrypt\n", crypto_blkdev);
+ goto errout;
+ }
+ }
+
+ *size_already_done += size;
+ rc = 0;
+
+errout:
+ close(realfd);
+ close(cryptofd);
+
+ return rc;
+}
+
+#define CRYPTO_ENABLE_WIPE 1
+#define CRYPTO_ENABLE_INPLACE 2
+
+#define FRAMEWORK_BOOT_WAIT 60
+
+static inline int should_encrypt(struct volume_info *volume)
+{
+ return (volume->flags & (VOL_ENCRYPTABLE | VOL_NONREMOVABLE)) ==
+ (VOL_ENCRYPTABLE | VOL_NONREMOVABLE);
+}
+
+int cryptfs_enable(char *howarg, char *passwd)
+{
+ // Code removed because it needs other parts of vold that aren't needed for decryption
+ return -1;
+}
+
+int cryptfs_changepw(char *newpw)
+{
+ struct crypt_mnt_ftr crypt_ftr;
+ unsigned char encrypted_master_key[KEY_LEN_BYTES], decrypted_master_key[KEY_LEN_BYTES];
+ unsigned char salt[SALT_LEN];
+ char real_blkdev[MAXPATHLEN];
+
+ /* This is only allowed after we've successfully decrypted the master key */
+ if (! master_key_saved) {
+ SLOGE("Key not saved, aborting");
+ return -1;
+ }
+
+ property_get("ro.crypto.fs_real_blkdev", real_blkdev, "");
+ if (strlen(real_blkdev) == 0) {
+ SLOGE("Can't find real blkdev");
+ return -1;
+ }
+
+ /* get key */
+ if (get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt)) {
+ SLOGE("Error getting crypt footer and key");
+ return -1;
+ }
+
+ encrypt_master_key(newpw, salt, saved_master_key, encrypted_master_key);
+
+ /* save the key */
+ put_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt);
+
+ return 0;
+}