diff options
Diffstat (limited to 'crypto/ics')
-rw-r--r-- | crypto/ics/Android.mk | 25 | ||||
-rw-r--r-- | crypto/ics/cryptfs.c | 729 | ||||
-rw-r--r-- | crypto/ics/cryptfs.h | 86 |
3 files changed, 840 insertions, 0 deletions
diff --git a/crypto/ics/Android.mk b/crypto/ics/Android.mk new file mode 100644 index 000000000..5616c195a --- /dev/null +++ b/crypto/ics/Android.mk @@ -0,0 +1,25 @@ +LOCAL_PATH := $(call my-dir) +ifeq ($(TW_INCLUDE_CRYPTO), true) +include $(CLEAR_VARS) + +LOCAL_MODULE := libcryptfsics +LOCAL_MODULE_TAGS := eng optional +LOCAL_CFLAGS := +LOCAL_CFLAGS += -DCRYPTO_FS_TYPE=\"$(TW_CRYPTO_FS_TYPE)\" +ifeq ($(TW_INCLUDE_CRYPTO_SAMSUNG), true) + LOCAL_CFLAGS += -DTW_INCLUDE_CRYPTO_SAMSUNG=\"$(TW_INCLUDE_CRYPTO_SAMSUNG)\" + LOCAL_LDFLAGS += -ldl + LOCAL_STATIC_LIBRARIES += libcrypt_samsung +endif +ifneq ($(TW_INTERNAL_STORAGE_PATH),) + LOCAL_CFLAGS += -DTW_INTERNAL_STORAGE_PATH=$(TW_INTERNAL_STORAGE_PATH) +endif +ifneq ($(TW_EXTERNAL_STORAGE_PATH),) + LOCAL_CFLAGS += -DTW_EXTERNAL_STORAGE_PATH=$(TW_EXTERNAL_STORAGE_PATH) +endif +LOCAL_SRC_FILES = cryptfs.c +LOCAL_C_INCLUDES += system/extras/ext4_utils external/openssl/include +LOCAL_SHARED_LIBRARIES += libc liblog libcutils libcrypto + +include $(BUILD_SHARED_LIBRARY) +endif diff --git a/crypto/ics/cryptfs.c b/crypto/ics/cryptfs.c new file mode 100644 index 000000000..4f3d5d01a --- /dev/null +++ b/crypto/ics/cryptfs.c @@ -0,0 +1,729 @@ +/* + * 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 +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG +#define KEY_LEN_BYTES_SAMSUNG (sizeof(edk_t)) +#endif +#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 + +#ifndef EXPAND +#define STRINGIFY(x) #x +#define EXPAND(x) STRINGIFY(x) +#endif + +char *me = "cryptfs"; + +static char *saved_data_blkdev; +static char *saved_mount_point; +static int master_key_saved = 0; +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG +static int using_samsung_encryption = 0; +//static edk_t saved_master_key; +static unsigned char saved_master_key[KEY_LEN_BYTES_SAMSUNG]; +edk_payload_t edk_payload; +#else +static unsigned char saved_master_key[KEY_LEN_BYTES]; +#endif + +int cryptfs_setup_volume(const char *label, const char *real_blkdev, char *crypto_blkdev); + + +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_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) +{ + // we don't need to update it... + return 0; +} + +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) { + printf("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) { + printf("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) { + printf("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 +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG + && statbuf.st_size != 0x8000 +#endif + )) { + printf("footer file %s is not the expected size!\n", fname); + goto errout; + } + } else { + printf("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)) { + printf("Cannot read real block device footer\n"); + goto errout; + } + + if (crypt_ftr->magic != CRYPT_MNT_MAGIC) { +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG + if (crypt_ftr->magic != CRYPT_MNT_MAGIC_SAMSUNG) { + printf("Bad magic for real block device %s\n", fname); + goto errout; + } else { + printf("Using Samsung encryption.\n"); + using_samsung_encryption = 1; + if ( (cnt = read(fd, &edk_payload, sizeof(edk_payload_t))) != sizeof(edk_payload_t)) { + printf("Cannot read EDK payload from real block device footer\n"); + goto errout; + } + if (lseek64(fd, sizeof(__le32), SEEK_CUR) == -1) { + printf("Cannot seek past unknown data from real block device footer\n"); + goto errout; + } + memcpy(key, &edk_payload, sizeof(edk_payload_t)); + } +#else + printf("Bad magic for real block device %s\n", fname); + goto errout; +#endif + } + + if (crypt_ftr->major_version != 1) { + printf("Cannot understand major version %d real block device footer\n", + crypt_ftr->major_version); + goto errout; + } + + if (crypt_ftr->minor_version != 0) { + printf("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 (lseek64(fd, crypt_ftr->ftr_size - sizeof(struct crypt_mnt_ftr), SEEK_CUR) == -1) { + printf("Cannot seek to start of key\n"); + goto errout; + } + } + + if (crypt_ftr->keysize > sizeof(saved_master_key)) { + printf("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) { + printf("Cannot read key for real block device %s\n", fname); + goto errout; + } + + if (lseek64(fd, KEY_TO_SALT_PADDING, SEEK_CUR) == -1) { + printf("Cannot seek to real block device salt\n"); + goto errout; + } + + if ( (cnt = read(fd, salt, SALT_LEN)) != SALT_LEN) { + printf("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, + const 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 ) { + printf("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)) { + printf("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)) { + printf("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); + //printf("cryptsetup params: '%s'\n", crypt_params); + 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)) { + printf("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)) { + printf("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(const 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 ) { + printf("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)) { + printf("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 decrypt_master_key(char *passwd, unsigned char *salt, + unsigned char *encrypted_master_key, + unsigned char *decrypted_master_key) +{ +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG + if (using_samsung_encryption) { + property_set("rw.km_fips_status", "ready"); + return decrypt_EDK((dek_t*)decrypted_master_key, (edk_payload_t*)encrypted_master_key, passwd); + } +#endif + + 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 get_orig_mount_parms( + const 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 get_orig_mount_parms_sd( + const char *mount_point, char *fs_type, char *real_blkdev) +{ + char mount_point2[PROPERTY_VALUE_MAX]; + + property_get("ro.crypto.sd_fs_type", fs_type, ""); + property_get("ro.crypto.sd_fs_real_blkdev", real_blkdev, ""); + property_get("ro.crypto.sd_fs_mnt_point", mount_point2, ""); + + if (strcmp(mount_point, mount_point2)) { + /* Consistency check. These should match. If not, something odd happened. */ + return -1; + } + + return 0; +} + +static int test_mount_encrypted_fs( + char *passwd, char *mount_point, char *label, char *crypto_blkdev) +{ + struct crypt_mnt_ftr crypt_ftr; + /* Allocate enough space for a 256 bit key, but we may use less */ + unsigned char encrypted_master_key[256], 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]; + char tmp_mount_point[MAXPATHLEN]; + 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") ) { + printf("encrypted fs already validated or not running with encryption, aborting %s\n", encrypted_state); + return -1; + } + + if (get_orig_mount_parms(mount_point, fs_type, real_blkdev, &mnt_flags, fs_options)) { + printf("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)) { + printf("Error getting crypt footer and key\n"); + return -1; + } + + //printf("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)) { + printf("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, fs_type, MS_RDONLY, "") ) { + printf("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; + } + + rmdir(tmp_mount_point); + + 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, sizeof(saved_master_key)); + saved_data_blkdev = strdup(real_blkdev); + saved_mount_point = strdup(mount_point); + master_key_saved = 1; + rc = 0; + } + + return rc; +} + +static int test_mount_encrypted_fs_sd( + const char *passwd, const char *mount_point, const char *label) +{ + char real_blkdev[MAXPATHLEN]; + char crypto_blkdev[MAXPATHLEN]; + char tmp_mount_point[MAXPATHLEN]; + char encrypted_state[PROPERTY_VALUE_MAX]; + char fs_type[PROPERTY_VALUE_MAX]; + int rc; + + property_get("ro.crypto.state", encrypted_state, ""); + if ( !master_key_saved || strcmp(encrypted_state, "encrypted") ) { + printf("encrypted fs not yet validated or not running with encryption, aborting\n"); + return -1; + } + + if (get_orig_mount_parms_sd(mount_point, fs_type, real_blkdev)) { + printf("Error reading original mount parms for mount point %s\n", mount_point); + return -1; + } + + rc = cryptfs_setup_volume(label, real_blkdev, crypto_blkdev); + if(rc){ + printf("Error setting up cryptfs volume %s\n", real_blkdev); + return -1; + } + + sprintf(tmp_mount_point, "%s/tmp_mnt", mount_point); + mkdir(tmp_mount_point, 0755); + if ( mount(crypto_blkdev, tmp_mount_point, fs_type, MS_RDONLY, "") ) { + printf("Error temp mounting decrypted block device\n"); + delete_crypto_blk_dev(label); + } else { + /* Success, so just umount and we'll mount it properly when we restart + * the framework. + */ + umount(tmp_mount_point); + + property_set("ro.crypto.sd_fs_crypto_blkdev", crypto_blkdev); + } + + rmdir(tmp_mount_point); + + return rc; +} + +/* + * 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, const char *real_blkdev, char *crypto_blkdev) +{ + struct crypt_mnt_ftr sd_crypt_ftr; + unsigned char key[256], salt[32]; + struct stat statbuf; + int nr_sec, fd, rc; + + /* 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; + } + +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG + if(using_samsung_encryption) { + if(!access("/efs/essiv", R_OK)){ + strcpy(sd_crypt_ftr.crypto_type_name, "aes-cbc-plain:sha1"); + } + else if(!access("/efs/cryptprop_essiv", R_OK)){ + strcpy(sd_crypt_ftr.crypto_type_name, "aes-cbc-essiv:sha256"); + } + } +#endif + + sd_crypt_ftr.fs_size = nr_sec; + rc = create_crypto_blk_dev( + &sd_crypt_ftr, saved_master_key, real_blkdev, crypto_blkdev, label); + + stat(crypto_blkdev, &statbuf); + + return rc; +} + +int cryptfs_crypto_complete(void) +{ + return -1; +} + +int cryptfs_check_footer(void) +{ + int rc = -1; + char fs_type[PROPERTY_VALUE_MAX]; + char real_blkdev[MAXPATHLEN]; + char fs_options[PROPERTY_VALUE_MAX]; + unsigned long mnt_flags; + struct crypt_mnt_ftr crypt_ftr; + /* Allocate enough space for a 256 bit key, but we may use less */ + unsigned char encrypted_master_key[256]; + unsigned char salt[SALT_LEN]; + + if (get_orig_mount_parms(DATA_MNT_POINT, fs_type, real_blkdev, &mnt_flags, fs_options)) { + printf("Error reading original mount parms for mount point %s\n", DATA_MNT_POINT); + return rc; + } + + rc = get_crypt_ftr_and_key(real_blkdev, &crypt_ftr, encrypted_master_key, salt); + + return rc; +} + +int cryptfs_check_passwd(const char *passwd) +{ + char pwbuf[256]; + char crypto_blkdev_data[MAXPATHLEN]; + int rc = -1; + + strcpy(pwbuf, passwd); + rc = test_mount_encrypted_fs(pwbuf, DATA_MNT_POINT, "userdata", crypto_blkdev_data); + +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG + if(using_samsung_encryption) { + + int rc2 = 1; +#ifndef RECOVERY_SDCARD_ON_DATA +#ifdef TW_INTERNAL_STORAGE_PATH + // internal storage for non data/media devices + if(!rc) { + strcpy(pwbuf, passwd); + rc2 = test_mount_encrypted_fs_sd( + pwbuf, EXPAND(TW_INTERNAL_STORAGE_PATH), + EXPAND(TW_INTERNAL_STORAGE_MOUNT_POINT)); + } +#endif +#endif +#ifdef TW_EXTERNAL_STORAGE_PATH + printf("Temp mounting /data\n"); + // mount data so mount_ecryptfs_drive can access edk in /data/system/ + rc2 = mount(crypto_blkdev_data, DATA_MNT_POINT, CRYPTO_FS_TYPE, MS_RDONLY, ""); + // external sd + char decrypt_external[256], external_blkdev[256]; + property_get("ro.crypto.external_encrypted", decrypt_external, "0"); + // Mount the external storage as ecryptfs so that ecryptfs can act as a pass-through + if (!rc2 && strcmp(decrypt_external, "1") == 0) { + printf("Mounting external with ecryptfs...\n"); + strcpy(pwbuf, passwd); + rc2 = mount_ecryptfs_drive( + pwbuf, EXPAND(TW_EXTERNAL_STORAGE_PATH), + EXPAND(TW_EXTERNAL_STORAGE_PATH), 0); + if (rc2 == 0) + property_set("ro.crypto.external_use_ecryptfs", "1"); + else + property_set("ro.crypto.external_use_ecryptfs", "0"); + } else { + printf("Unable to mount external storage with ecryptfs.\n"); + umount(EXPAND(TW_EXTERNAL_STORAGE_PATH)); + } + umount(DATA_MNT_POINT); + } +#endif // #ifdef TW_EXTERNAL_STORAGE_PATH +#endif // #ifdef TW_INCLUDE_CRYPTO_SAMSUNG + return rc; +} diff --git a/crypto/ics/cryptfs.h b/crypto/ics/cryptfs.h new file mode 100644 index 000000000..8c8037659 --- /dev/null +++ b/crypto/ics/cryptfs.h @@ -0,0 +1,86 @@ +/* + * 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. + */ + +/* This structure starts 16,384 bytes before the end of a hardware + * partition that is encrypted. + * Immediately following this structure is the encrypted key. + * The keysize field tells how long the key is, in bytes. + * Then there is 32 bytes of padding, + * Finally there is the salt used with the user password. + * The salt is fixed at 16 bytes long. + * Obviously, the filesystem does not include the last 16 kbytes + * of the partition. + */ + +#ifndef __CRYPTFS_H__ +#define __CRYPTFS_H__ + +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG +#include "../libcrypt_samsung/include/libcrypt_samsung.h" +#endif + +#define CRYPT_FOOTER_OFFSET 0x4000 + +#define MAX_CRYPTO_TYPE_NAME_LEN 64 + +#define SALT_LEN 16 +#define KEY_TO_SALT_PADDING 32 + +/* definitions of flags in the structure below */ +#define CRYPT_MNT_KEY_UNENCRYPTED 0x1 /* The key for the partition is not encrypted. */ +#define CRYPT_ENCRYPTION_IN_PROGRESS 0x2 /* Set when starting encryption, + * clear when done before rebooting */ + +#ifdef TW_INCLUDE_CRYPTO_SAMSUNG +#define CRYPT_MNT_MAGIC_SAMSUNG 0xD0B5B1C5 +#endif +#define CRYPT_MNT_MAGIC 0xD0B5B1C4 + +#define __le32 unsigned int +#define __le16 unsigned short int + +#pragma pack(1) + +struct crypt_mnt_ftr { + __le32 magic; /* See above */ + __le16 major_version; + __le16 minor_version; + __le32 ftr_size; /* in bytes, not including key following */ + __le32 flags; /* See above */ + __le32 keysize; /* in bytes */ + __le32 spare1; /* ignored */ + __le64 fs_size; /* Size of the encrypted fs, in 512 byte sectors */ + __le32 failed_decrypt_count; /* count of # of failed attempts to decrypt and + mount, set to 0 on successful mount */ + char crypto_type_name[MAX_CRYPTO_TYPE_NAME_LEN]; /* The type of encryption + needed to decrypt this + partition, null terminated */ +}; + +#pragma pack() + + +#ifdef __cplusplus +extern "C" { +#endif + int cryptfs_check_footer(void); + int cryptfs_check_passwd(const char *pw); +#ifdef __cplusplus +} +#endif + +#endif // __CRYPTFS_H__ + |