From 4eca40d7d8ff6968ed68a24686093cfb6f5f6373 Mon Sep 17 00:00:00 2001 From: Ethan Yonker Date: Tue, 11 Nov 2014 14:52:28 -0600 Subject: Add lollipop decrypt support Kang in cryptfs.c and cryptfs.h from vold. Use TW_INCLUDE_L_CRYPTO := true to enable. Ramdisk must contain the normal fstab file in the root in the usual format of: fstab.{ro.hardware} For examble for Nexus 5: fstab.hammerhead Or on many Qualcomm devices: fstab.qcom Tested against Android 5.0 lollipop on Nexus 7 2012 grouper. Not sure if or how this will work when we are dealing with a device with a hardware keystore. Long term we need to add a GUI element to allow entering a pattern. For now you can decrypt a pattern unlock by converting the dots to numbers in the following format: 123 456 789 So an upper-case L would translate to 14789 as a password entered on the keyboard. Change-Id: I02c29e1f1c2eb29bf002c9fe0fc118357300b5b3 --- crypto/lollipop/Android.mk | 52 + crypto/lollipop/cryptfs.c | 3620 ++++++++++++++++++++++++++++++++++++++++++++ crypto/lollipop/cryptfs.h | 231 +++ 3 files changed, 3903 insertions(+) create mode 100644 crypto/lollipop/Android.mk create mode 100644 crypto/lollipop/cryptfs.c create mode 100644 crypto/lollipop/cryptfs.h (limited to 'crypto') diff --git a/crypto/lollipop/Android.mk b/crypto/lollipop/Android.mk new file mode 100644 index 000000000..cce070b56 --- /dev/null +++ b/crypto/lollipop/Android.mk @@ -0,0 +1,52 @@ +LOCAL_PATH := $(call my-dir) +ifeq ($(TW_INCLUDE_L_CRYPTO), true) +include $(CLEAR_VARS) + +common_c_includes := \ + system/extras/ext4_utils \ + system/extras/f2fs_utils \ + external/openssl/include \ + external/stlport/stlport \ + bionic \ + external/scrypt/lib/crypto \ + frameworks/native/include \ + system/security/keystore \ + hardware/libhardware/include/hardware \ + system/security/softkeymaster/include/keymaster + +common_shared_libraries := \ + libsysutils \ + libstlport \ + libbinder \ + libcutils \ + liblog \ + libdiskconfig \ + libhardware_legacy \ + liblogwrap \ + libext4_utils \ + libf2fs_sparseblock \ + libcrypto \ + libselinux \ + libutils \ + libhardware \ + libsoftkeymaster + +LOCAL_MODULE := libcryptfslollipop +LOCAL_MODULE_TAGS := eng optional +LOCAL_CFLAGS := +LOCAL_SRC_FILES = cryptfs.c +#LOCAL_C_INCLUDES += \ +# system/extras/ext4_utils \ +# external/openssl/include \ +# system/extras/f2fs_utils \ +# external/scrypt/lib/crypto \ +# system/security/keystore \ +# hardware/libhardware/include/hardware \ +# system/security/softkeymaster/include/keymaster +#LOCAL_SHARED_LIBRARIES += libc liblog libcutils libcrypto libext4_utils +LOCAL_SHARED_LIBRARIES := $(common_shared_libraries) +LOCAL_C_INCLUDES := external/openssl/include $(common_c_includes) +LOCAL_STATIC_LIBRARIES += libfs_mgr libscrypt_static liblogwrap libmincrypttwrp + +include $(BUILD_SHARED_LIBRARY) +endif diff --git a/crypto/lollipop/cryptfs.c b/crypto/lollipop/cryptfs.c new file mode 100644 index 000000000..630fb0ee3 --- /dev/null +++ b/crypto/lollipop/cryptfs.c @@ -0,0 +1,3620 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "cryptfs.h" +#define LOG_TAG "Cryptfs" +#include "cutils/log.h" +#include "cutils/properties.h" +#include "cutils/android_reboot.h" +#include "hardware_legacy/power.h" +#include +//#include "VolumeManager.h" +//#include "VoldUtil.h" +#include "crypto_scrypt.h" +#include "ext4_utils.h" +#include "f2fs_sparseblock.h" +//#include "CheckBattery.h" +//#include "Process.h" + +#include + +#define UNUSED __attribute__((unused)) + +#define UNUSED __attribute__((unused)) + +#define DM_CRYPT_BUF_SIZE 4096 + +#define HASH_COUNT 2000 +#define KEY_LEN_BYTES 16 +#define IV_LEN_BYTES 16 + +#define KEY_IN_FOOTER "footer" + +// "default_password" encoded into hex (d=0x64 etc) +#define DEFAULT_PASSWORD "64656661756c745f70617373776f7264" + +#define EXT4_FS 1 +#define F2FS_FS 2 + +#define TABLE_LOAD_RETRIES 10 + +#define RSA_KEY_SIZE 2048 +#define RSA_KEY_SIZE_BYTES (RSA_KEY_SIZE / 8) +#define RSA_EXPONENT 0x10001 + +#define RETRY_MOUNT_ATTEMPTS 10 +#define RETRY_MOUNT_DELAY_SECONDS 1 + +char *me = "cryptfs"; + +static unsigned char saved_master_key[KEY_LEN_BYTES]; +static char *saved_mount_point; +static int master_key_saved = 0; +static struct crypt_persist_data *persist_data = NULL; + +static int keymaster_init(keymaster_device_t **keymaster_dev) +{ + int rc; + + const hw_module_t* mod; + rc = hw_get_module_by_class(KEYSTORE_HARDWARE_MODULE_ID, NULL, &mod); + if (rc) { + printf("could not find any keystore module\n"); + goto out; + } + + rc = keymaster_open(mod, keymaster_dev); + if (rc) { + printf("could not open keymaster device in %s (%s)\n", + KEYSTORE_HARDWARE_MODULE_ID, strerror(-rc)); + goto out; + } + + return 0; + +out: + *keymaster_dev = NULL; + return rc; +} + +/* Should we use keymaster? */ +static int keymaster_check_compatibility() +{ + keymaster_device_t *keymaster_dev = 0; + int rc = 0; + + if (keymaster_init(&keymaster_dev)) { + printf("Failed to init keymaster\n"); + rc = -1; + goto out; + } + + printf("keymaster version is %d\n", keymaster_dev->common.module->module_api_version); + + if (keymaster_dev->common.module->module_api_version + < KEYMASTER_MODULE_API_VERSION_0_3) { + rc = 0; + goto out; + } + + if (keymaster_dev->flags & KEYMASTER_BLOBS_ARE_STANDALONE) { + rc = 1; + } + +out: + keymaster_close(keymaster_dev); + return rc; +} + +/* Create a new keymaster key and store it in this footer */ +static int keymaster_create_key(struct crypt_mnt_ftr *ftr) +{ + uint8_t* key = 0; + keymaster_device_t *keymaster_dev = 0; + + if (keymaster_init(&keymaster_dev)) { + printf("Failed to init keymaster\n"); + return -1; + } + + int rc = 0; + + keymaster_rsa_keygen_params_t params; + memset(¶ms, '\0', sizeof(params)); + params.public_exponent = RSA_EXPONENT; + params.modulus_size = RSA_KEY_SIZE; + + size_t key_size; + if (keymaster_dev->generate_keypair(keymaster_dev, TYPE_RSA, ¶ms, + &key, &key_size)) { + printf("Failed to generate keypair\n"); + rc = -1; + goto out; + } + + if (key_size > KEYMASTER_BLOB_SIZE) { + printf("Keymaster key too large for crypto footer\n"); + rc = -1; + goto out; + } + + memcpy(ftr->keymaster_blob, key, key_size); + ftr->keymaster_blob_size = key_size; + +out: + keymaster_close(keymaster_dev); + free(key); + return rc; +} + +/* This signs the given object using the keymaster key. */ +static int keymaster_sign_object(struct crypt_mnt_ftr *ftr, + const unsigned char *object, + const size_t object_size, + unsigned char **signature, + size_t *signature_size) +{ + int rc = 0; + keymaster_device_t *keymaster_dev = 0; + if (keymaster_init(&keymaster_dev)) { + printf("Failed to init keymaster\n"); + return -1; + } + + /* We currently set the digest type to DIGEST_NONE because it's the + * only supported value for keymaster. A similar issue exists with + * PADDING_NONE. Long term both of these should likely change. + */ + keymaster_rsa_sign_params_t params; + params.digest_type = DIGEST_NONE; + params.padding_type = PADDING_NONE; + + unsigned char to_sign[RSA_KEY_SIZE_BYTES]; + size_t to_sign_size = sizeof(to_sign); + memset(to_sign, 0, RSA_KEY_SIZE_BYTES); + + // To sign a message with RSA, the message must satisfy two + // constraints: + // + // 1. The message, when interpreted as a big-endian numeric value, must + // be strictly less than the public modulus of the RSA key. Note + // that because the most significant bit of the public modulus is + // guaranteed to be 1 (else it's an (n-1)-bit key, not an n-bit + // key), an n-bit message with most significant bit 0 always + // satisfies this requirement. + // + // 2. The message must have the same length in bits as the public + // modulus of the RSA key. This requirement isn't mathematically + // necessary, but is necessary to ensure consistency in + // implementations. + switch (ftr->kdf_type) { + case KDF_SCRYPT_KEYMASTER_UNPADDED: + // This is broken: It produces a message which is shorter than + // the public modulus, failing criterion 2. + memcpy(to_sign, object, object_size); + to_sign_size = object_size; + printf("Signing unpadded object\n"); + break; + case KDF_SCRYPT_KEYMASTER_BADLY_PADDED: + // This is broken: Since the value of object is uniformly + // distributed, it produces a message that is larger than the + // public modulus with probability 0.25. + memcpy(to_sign, object, min(RSA_KEY_SIZE_BYTES, object_size)); + printf("Signing end-padded object\n"); + break; + case KDF_SCRYPT_KEYMASTER: + // This ensures the most significant byte of the signed message + // is zero. We could have zero-padded to the left instead, but + // this approach is slightly more robust against changes in + // object size. However, it's still broken (but not unusably + // so) because we really should be using a proper RSA padding + // function, such as OAEP. + // + // TODO(paullawrence): When keymaster 0.4 is available, change + // this to use the padding options it provides. + memcpy(to_sign + 1, object, min(RSA_KEY_SIZE_BYTES - 1, object_size)); + printf("Signing safely-padded object\n"); + break; + default: + printf("Unknown KDF type %d\n", ftr->kdf_type); + return -1; + } + + rc = keymaster_dev->sign_data(keymaster_dev, + ¶ms, + ftr->keymaster_blob, + ftr->keymaster_blob_size, + to_sign, + to_sign_size, + signature, + signature_size); + + keymaster_close(keymaster_dev); + return rc; +} + +/* Store password when userdata is successfully decrypted and mounted. + * Cleared by cryptfs_clear_password + * + * To avoid a double prompt at boot, we need to store the CryptKeeper + * password and pass it to KeyGuard, which uses it to unlock KeyStore. + * Since the entire framework is torn down and rebuilt after encryption, + * we have to use a daemon or similar to store the password. Since vold + * is secured against IPC except from system processes, it seems a reasonable + * place to store this. + * + * password should be cleared once it has been used. + * + * password is aged out after password_max_age_seconds seconds. + */ +static char* password = 0; +static int password_expiry_time = 0; +static const int password_max_age_seconds = 60; + +struct fstab *fstab; + +enum RebootType {reboot, recovery, shutdown}; +static void cryptfs_reboot(enum RebootType rt) +{ + switch(rt) { + case reboot: + property_set(ANDROID_RB_PROPERTY, "reboot"); + break; + + case recovery: + property_set(ANDROID_RB_PROPERTY, "reboot,recovery"); + break; + + case shutdown: + property_set(ANDROID_RB_PROPERTY, "shutdown"); + break; + } + + sleep(20); + + /* Shouldn't get here, reboot should happen before sleep times out */ + return; +} + +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)); + } +} + +/** + * Gets the default device scrypt parameters for key derivation time tuning. + * The parameters should lead to about one second derivation time for the + * given device. + */ +static void get_device_scrypt_params(struct crypt_mnt_ftr *ftr) { + const int default_params[] = SCRYPT_DEFAULTS; + int params[] = SCRYPT_DEFAULTS; + char paramstr[PROPERTY_VALUE_MAX]; + char *token; + char *saveptr; + int i; + + property_get(SCRYPT_PROP, paramstr, ""); + if (paramstr[0] != '\0') { + /* + * The token we're looking for should be three integers separated by + * colons (e.g., "12:8:1"). Scan the property to make sure it matches. + */ + for (i = 0, token = strtok_r(paramstr, ":", &saveptr); + token != NULL && i < 3; + i++, token = strtok_r(NULL, ":", &saveptr)) { + char *endptr; + params[i] = strtol(token, &endptr, 10); + + /* + * Check that there was a valid number and it's 8-bit. If not, + * break out and the end check will take the default values. + */ + if ((*token == '\0') || (*endptr != '\0') || params[i] < 0 || params[i] > 255) { + break; + } + } + + /* + * If there were not enough tokens or a token was malformed (not an + * integer), it will end up here and the default parameters can be + * taken. + */ + if ((i != 3) || (token != NULL)) { + printf("bad scrypt parameters '%s' should be like '12:8:1'; using defaults", paramstr); + memcpy(params, default_params, sizeof(params)); + } + } + + ftr->N_factor = params[0]; + ftr->r_factor = params[1]; + ftr->p_factor = params[2]; +} + +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) { + printf("Cannot open device to get filesystem size "); + return 0; + } + + if (lseek64(fd, 1024, SEEK_SET) < 0) { + printf("Cannot seek to superblock"); + return 0; + } + + if (read(fd, &sb, sizeof(sb)) != sizeof(sb)) { + printf("Cannot read superblock"); + return 0; + } + + close(fd); + + if (le32_to_cpu(sb.s_magic) != EXT4_SUPER_MAGIC) { + printf("Not a valid ext4 superblock"); + return 0; + } + 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; +} + +static int get_crypt_ftr_info(char **metadata_fname, off64_t *off) +{ + static int cached_data = 0; + static off64_t cached_off = 0; + static char cached_metadata_fname[PROPERTY_VALUE_MAX] = ""; + int fd; + char key_loc[PROPERTY_VALUE_MAX]; + char real_blkdev[PROPERTY_VALUE_MAX]; + unsigned int nr_sec; + int rc = -1; + + if (!cached_data) { + fs_mgr_get_crypt_info(fstab, key_loc, real_blkdev, sizeof(key_loc)); + printf("get_crypt_ftr_info crypto key location: '%s'\n", key_loc); + if (!strcmp(key_loc, KEY_IN_FOOTER)) { + if ( (fd = open(real_blkdev, O_RDWR)) < 0) { + printf("Cannot open real block device %s\n", real_blkdev); + return -1; + } + + if ((nr_sec = get_blkdev_size(fd))) { + /* 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. + */ + strlcpy(cached_metadata_fname, real_blkdev, sizeof(cached_metadata_fname)); + cached_off = ((off64_t)nr_sec * 512) - CRYPT_FOOTER_OFFSET; + cached_data = 1; + } else { + printf("Cannot get size of block device %s\n", real_blkdev); + } + close(fd); + } else { + strlcpy(cached_metadata_fname, key_loc, sizeof(cached_metadata_fname)); + cached_off = 0; + cached_data = 1; + } + } + + if (cached_data) { + if (metadata_fname) { + *metadata_fname = cached_metadata_fname; + } + if (off) { + *off = cached_off; + } + rc = 0; + } + + return rc; +} + +/* 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(struct crypt_mnt_ftr *crypt_ftr) +{ + printf("TWRP NOT putting crypt footer and key\n"); + return 0; + int fd; + unsigned int nr_sec, cnt; + /* starting_off is set to the SEEK_SET offset + * where the crypto structure starts + */ + off64_t starting_off; + int rc = -1; + char *fname = NULL; + struct stat statbuf; + + if (get_crypt_ftr_info(&fname, &starting_off)) { + printf("Unable to get crypt_ftr_info\n"); + return -1; + } + if (fname[0] != '/') { + printf("Unexpected value for crypto key location\n"); + return -1; + } + if ( (fd = open(fname, O_RDWR | O_CREAT, 0600)) < 0) { + printf("Cannot open footer file %s for put\n", fname); + return -1; + } + + /* Seek to the start of the crypt footer */ + if (lseek64(fd, starting_off, SEEK_SET) == -1) { + printf("Cannot seek to real block device footer\n"); + goto errout; + } + + if ((cnt = write(fd, crypt_ftr, sizeof(struct crypt_mnt_ftr))) != sizeof(struct crypt_mnt_ftr)) { + printf("Cannot write real block device footer\n"); + 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)) { + if (ftruncate(fd, 0x4000)) { + printf("Cannot set footer file size\n"); + goto errout; + } + } + + /* Success! */ + rc = 0; + +errout: + close(fd); + return rc; + +} + +static inline int unix_read(int fd, void* buff, int len) +{ + return TEMP_FAILURE_RETRY(read(fd, buff, len)); +} + +static inline int unix_write(int fd, const void* buff, int len) +{ + return TEMP_FAILURE_RETRY(write(fd, buff, len)); +} + +static void init_empty_persist_data(struct crypt_persist_data *pdata, int len) +{ + memset(pdata, 0, len); + pdata->persist_magic = PERSIST_DATA_MAGIC; + pdata->persist_valid_entries = 0; +} + +/* A routine to update the passed in crypt_ftr to the lastest version. + * fd is open read/write on the device that holds the crypto footer and persistent + * data, crypt_ftr is a pointer to the struct to be updated, and offset is the + * absolute offset to the start of the crypt_mnt_ftr on the passed in fd. + */ +static void upgrade_crypt_ftr(int fd, struct crypt_mnt_ftr *crypt_ftr, off64_t offset) +{ + int orig_major = crypt_ftr->major_version; + int orig_minor = crypt_ftr->minor_version; +printf("TWRP NOT upgrading crypto footer\n"); +return; // do not upgrade in recovery + if ((crypt_ftr->major_version == 1) && (crypt_ftr->minor_version == 0)) { + struct crypt_persist_data *pdata; + off64_t pdata_offset = offset + CRYPT_FOOTER_TO_PERSIST_OFFSET; + + printf("upgrading crypto footer to 1.1"); + + pdata = malloc(CRYPT_PERSIST_DATA_SIZE); + if (pdata == NULL) { + printf("Cannot allocate persisent data\n"); + return; + } + memset(pdata, 0, CRYPT_PERSIST_DATA_SIZE); + + /* Need to initialize the persistent data area */ + if (lseek64(fd, pdata_offset, SEEK_SET) == -1) { + printf("Cannot seek to persisent data offset\n"); + return; + } + /* Write all zeros to the first copy, making it invalid */ + unix_write(fd, pdata, CRYPT_PERSIST_DATA_SIZE); + + /* Write a valid but empty structure to the second copy */ + init_empty_persist_data(pdata, CRYPT_PERSIST_DATA_SIZE); + unix_write(fd, pdata, CRYPT_PERSIST_DATA_SIZE); + + /* Update the footer */ + crypt_ftr->persist_data_size = CRYPT_PERSIST_DATA_SIZE; + crypt_ftr->persist_data_offset[0] = pdata_offset; + crypt_ftr->persist_data_offset[1] = pdata_offset + CRYPT_PERSIST_DATA_SIZE; + crypt_ftr->minor_version = 1; + } + + if ((crypt_ftr->major_version == 1) && (crypt_ftr->minor_version == 1)) { + printf("upgrading crypto footer to 1.2"); + /* But keep the old kdf_type. + * It will get updated later to KDF_SCRYPT after the password has been verified. + */ + crypt_ftr->kdf_type = KDF_PBKDF2; + get_device_scrypt_params(crypt_ftr); + crypt_ftr->minor_version = 2; + } + + if ((crypt_ftr->major_version == 1) && (crypt_ftr->minor_version == 2)) { + printf("upgrading crypto footer to 1.3"); + crypt_ftr->crypt_type = CRYPT_TYPE_PASSWORD; + crypt_ftr->minor_version = 3; + } + + if ((orig_major != crypt_ftr->major_version) || (orig_minor != crypt_ftr->minor_version)) { + if (lseek64(fd, offset, SEEK_SET) == -1) { + printf("Cannot seek to crypt footer\n"); + return; + } + unix_write(fd, crypt_ftr, sizeof(struct crypt_mnt_ftr)); + } +} + + +static int get_crypt_ftr_and_key(struct crypt_mnt_ftr *crypt_ftr) +{ + int fd; + unsigned int nr_sec, cnt; + off64_t starting_off; + int rc = -1; + char *fname = NULL; + struct stat statbuf; + + if (get_crypt_ftr_info(&fname, &starting_off)) { + printf("Unable to get crypt_ftr_info\n"); + return -1; + } + if (fname[0] != '/') { + printf("Unexpected value for crypto key location\n"); + return -1; + } + if ( (fd = open(fname, O_RDWR)) < 0) { + printf("Cannot open footer file %s for get\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)) { + printf("footer file %s is not the expected size!\n", fname); + goto errout; + } + + /* Seek to the start of the crypt footer */ + if (lseek64(fd, starting_off, SEEK_SET) == -1) { + printf("Cannot seek to real block device footer\n"); + goto errout; + } + + 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) { + printf("Bad magic for real block device %s\n", fname); + goto errout; + } + + if (crypt_ftr->major_version != CURRENT_MAJOR_VERSION) { + printf("Cannot understand major version %d real block device footer; expected %d\n", + crypt_ftr->major_version, CURRENT_MAJOR_VERSION); + goto errout; + } + + if (crypt_ftr->minor_version > CURRENT_MINOR_VERSION) { + printf("Warning: crypto footer minor version %d, expected <= %d, continuing...\n", + crypt_ftr->minor_version, CURRENT_MINOR_VERSION); + } + + /* If this is a verion 1.0 crypt_ftr, make it a 1.1 crypt footer, and update the + * copy on disk before returning. + */ + if (crypt_ftr->minor_version < CURRENT_MINOR_VERSION) { + upgrade_crypt_ftr(fd, crypt_ftr, starting_off); + } + + /* Success! */ + rc = 0; + +errout: + close(fd); + return rc; +} + +static int validate_persistent_data_storage(struct crypt_mnt_ftr *crypt_ftr) +{ + if (crypt_ftr->persist_data_offset[0] + crypt_ftr->persist_data_size > + crypt_ftr->persist_data_offset[1]) { + printf("Crypt_ftr persist data regions overlap"); + return -1; + } + + if (crypt_ftr->persist_data_offset[0] >= crypt_ftr->persist_data_offset[1]) { + printf("Crypt_ftr persist data region 0 starts after region 1"); + return -1; + } + + if (((crypt_ftr->persist_data_offset[1] + crypt_ftr->persist_data_size) - + (crypt_ftr->persist_data_offset[0] - CRYPT_FOOTER_TO_PERSIST_OFFSET)) > + CRYPT_FOOTER_OFFSET) { + printf("Persistent data extends past crypto footer"); + return -1; + } + + return 0; +} + +static int load_persistent_data(void) +{ + struct crypt_mnt_ftr crypt_ftr; + struct crypt_persist_data *pdata = NULL; + char encrypted_state[PROPERTY_VALUE_MAX]; + char *fname; + int found = 0; + int fd; + int ret; + int i; + + if (persist_data) { + /* Nothing to do, we've already loaded or initialized it */ + return 0; + } + + + /* If not encrypted, just allocate an empty table and initialize it */ + property_get("ro.crypto.state", encrypted_state, ""); + if (strcmp(encrypted_state, "encrypted") ) { + pdata = malloc(CRYPT_PERSIST_DATA_SIZE); + if (pdata) { + init_empty_persist_data(pdata, CRYPT_PERSIST_DATA_SIZE); + persist_data = pdata; + return 0; + } + return -1; + } + + if(get_crypt_ftr_and_key(&crypt_ftr)) { + return -1; + } + + if ((crypt_ftr.major_version < 1) + || (crypt_ftr.major_version == 1 && crypt_ftr.minor_version < 1)) { + printf("Crypt_ftr version doesn't support persistent data"); + return -1; + } + + if (get_crypt_ftr_info(&fname, NULL)) { + return -1; + } + + ret = validate_persistent_data_storage(&crypt_ftr); + if (ret) { + return -1; + } + + fd = open(fname, O_RDONLY); + if (fd < 0) { + printf("Cannot open %s metadata file", fname); + return -1; + } + + if (persist_data == NULL) { + pdata = malloc(crypt_ftr.persist_data_size); + if (pdata == NULL) { + printf("Cannot allocate memory for persistent data"); + goto err; + } + } + + for (i = 0; i < 2; i++) { + if (lseek64(fd, crypt_ftr.persist_data_offset[i], SEEK_SET) < 0) { + printf("Cannot seek to read persistent data on %s", fname); + goto err2; + } + if (unix_read(fd, pdata, crypt_ftr.persist_data_size) < 0){ + printf("Error reading persistent data on iteration %d", i); + goto err2; + } + if (pdata->persist_magic == PERSIST_DATA_MAGIC) { + found = 1; + break; + } + } + + if (!found) { + printf("Could not find valid persistent data, creating"); + init_empty_persist_data(pdata, crypt_ftr.persist_data_size); + } + + /* Success */ + persist_data = pdata; + close(fd); + return 0; + +err2: + free(pdata); + +err: + close(fd); + return -1; +} + +static int save_persistent_data(void) +{ + struct crypt_mnt_ftr crypt_ftr; + struct crypt_persist_data *pdata; + char *fname; + off64_t write_offset; + off64_t erase_offset; + int found = 0; + int fd; + int ret; + + if (persist_data == NULL) { + printf("No persistent data to save"); + return -1; + } + + if(get_crypt_ftr_and_key(&crypt_ftr)) { + return -1; + } + + if ((crypt_ftr.major_version < 1) + || (crypt_ftr.major_version == 1 && crypt_ftr.minor_version < 1)) { + printf("Crypt_ftr version doesn't support persistent data"); + return -1; + } + + ret = validate_persistent_data_storage(&crypt_ftr); + if (ret) { + return -1; + } + + if (get_crypt_ftr_info(&fname, NULL)) { + return -1; + } + + fd = open(fname, O_RDWR); + if (fd < 0) { + printf("Cannot open %s metadata file", fname); + return -1; + } + + pdata = malloc(crypt_ftr.persist_data_size); + if (pdata == NULL) { + printf("Cannot allocate persistant data"); + goto err; + } + + if (lseek64(fd, crypt_ftr.persist_data_offset[0], SEEK_SET) < 0) { + printf("Cannot seek to read persistent data on %s", fname); + goto err2; + } + + if (unix_read(fd, pdata, crypt_ftr.persist_data_size) < 0) { + printf("Error reading persistent data before save"); + goto err2; + } + + if (pdata->persist_magic == PERSIST_DATA_MAGIC) { + /* The first copy is the curent valid copy, so write to + * the second copy and erase this one */ + write_offset = crypt_ftr.persist_data_offset[1]; + erase_offset = crypt_ftr.persist_data_offset[0]; + } else { + /* The second copy must be the valid copy, so write to + * the first copy, and erase the second */ + write_offset = crypt_ftr.persist_data_offset[0]; + erase_offset = crypt_ftr.persist_data_offset[1]; + } + + /* Write the new copy first, if successful, then erase the old copy */ + if (lseek(fd, write_offset, SEEK_SET) < 0) { + printf("Cannot seek to write persistent data"); + goto err2; + } + if (unix_write(fd, persist_data, crypt_ftr.persist_data_size) == + (int) crypt_ftr.persist_data_size) { + if (lseek(fd, erase_offset, SEEK_SET) < 0) { + printf("Cannot seek to erase previous persistent data"); + goto err2; + } + fsync(fd); + memset(pdata, 0, crypt_ftr.persist_data_size); + if (unix_write(fd, pdata, crypt_ftr.persist_data_size) != + (int) crypt_ftr.persist_data_size) { + printf("Cannot write to erase previous persistent data"); + goto err2; + } + fsync(fd); + } else { + printf("Cannot write to save persistent data"); + goto err2; + } + + /* Success */ + free(pdata); + close(fd); + return 0; + +err2: + free(pdata); +err: + close(fd); + return -1; +} + +static int hexdigit (char c) +{ + if (c >= '0' && c <= '9') return c - '0'; + c = tolower(c); + if (c >= 'a' && c <= 'f') return c - 'a' + 10; + return -1; +} + +static unsigned char* convert_hex_ascii_to_key(const char* master_key_ascii, + unsigned int* out_keysize) +{ + unsigned int i; + *out_keysize = 0; + + size_t size = strlen (master_key_ascii); + if (size % 2) { + printf("Trying to convert ascii string of odd length"); + return NULL; + } + + unsigned char* master_key = (unsigned char*) malloc(size / 2); + if (master_key == 0) { + printf("Cannot allocate"); + return NULL; + } + + for (i = 0; i < size; i += 2) { + int high_nibble = hexdigit (master_key_ascii[i]); + int low_nibble = hexdigit (master_key_ascii[i + 1]); + + if(high_nibble < 0 || low_nibble < 0) { + printf("Invalid hex string"); + free (master_key); + return NULL; + } + + master_key[*out_keysize] = high_nibble * 16 + low_nibble; + (*out_keysize)++; + } + + return master_key; +} + +/* Convert a binary key of specified length into an ascii hex string equivalent, + * without the leading 0x and with null termination + */ +static 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> 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 load_crypto_mapping_table(struct crypt_mnt_ftr *crypt_ftr, unsigned char *master_key, + char *real_blk_name, const char *name, int fd, + char *extra_params) +{ + char buffer[DM_CRYPT_BUF_SIZE]; + struct dm_ioctl *io; + struct dm_target_spec *tgt; + char *crypt_params; + char master_key_ascii[129]; /* Large enough to hold 512 bit key and null */ + int i; + + io = (struct dm_ioctl *) buffer; + + /* Load the mapping table for this device */ + tgt = (struct dm_target_spec *) &buffer[sizeof(struct dm_ioctl)]; + + ioctl_init(io, DM_CRYPT_BUF_SIZE, 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 %s", crypt_ftr->crypto_type_name, + master_key_ascii, real_blk_name, extra_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; + + for (i = 0; i < TABLE_LOAD_RETRIES; i++) { + if (! ioctl(fd, DM_TABLE_LOAD, io)) { + break; + } + usleep(500000); + } + + if (i == TABLE_LOAD_RETRIES) { + /* We failed to load the table, return an error */ + return -1; + } else { + return i + 1; + } +} + + +static int get_dm_crypt_version(int fd, const char *name, int *version) +{ + char buffer[DM_CRYPT_BUF_SIZE]; + struct dm_ioctl *io; + struct dm_target_versions *v; + int i; + + io = (struct dm_ioctl *) buffer; + + ioctl_init(io, DM_CRYPT_BUF_SIZE, name, 0); + + if (ioctl(fd, DM_LIST_VERSIONS, io)) { + return -1; + } + + /* Iterate over the returned versions, looking for name of "crypt". + * When found, get and return the version. + */ + v = (struct dm_target_versions *) &buffer[sizeof(struct dm_ioctl)]; + while (v->next) { + if (! strcmp(v->name, "crypt")) { + /* We found the crypt driver, return the version, and get out */ + version[0] = v->version[0]; + version[1] = v->version[1]; + version[2] = v->version[2]; + return 0; + } + v = (struct dm_target_versions *)(((char *)v) + v->next); + } + + return -1; +} + +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 i; + int retval = -1; + int version[3]; + char *extra_params; + int load_count; + + 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); + + extra_params = ""; + if (! get_dm_crypt_version(fd, name, version)) { + /* Support for allow_discards was added in version 1.11.0 */ + if ((version[0] >= 2) || + ((version[0] == 1) && (version[1] >= 11))) { + extra_params = "1 allow_discards"; + printf("Enabling support for allow_discards in dmcrypt.\n"); + } + } + + load_count = load_crypto_mapping_table(crypt_ftr, master_key, real_blk_name, name, + fd, extra_params); + if (load_count < 0) { + printf("Cannot load dm-crypt mapping table.\n"); + goto errout; + } else if (load_count > 1) { + printf("Took %d tries to load dmcrypt table.\n", load_count); + } + + /* Resume this device to activate it */ + ioctl_init(io, DM_CRYPT_BUF_SIZE, 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(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 int pbkdf2(const char *passwd, const unsigned char *salt, + unsigned char *ikey, void *params UNUSED) +{ + printf("Using pbkdf2 for cryptfs KDF"); + + /* Turn the password into a key and IV that can decrypt the master key */ + unsigned int keysize; + char* master_key = (char*)convert_hex_ascii_to_key(passwd, &keysize); + if (!master_key) return -1; + PKCS5_PBKDF2_HMAC_SHA1(master_key, keysize, salt, SALT_LEN, + HASH_COUNT, KEY_LEN_BYTES+IV_LEN_BYTES, ikey); + + memset(master_key, 0, keysize); + free (master_key); + return 0; +} + +static int scrypt(const char *passwd, const unsigned char *salt, + unsigned char *ikey, void *params) +{ + printf("Using scrypt for cryptfs KDF\n"); + + struct crypt_mnt_ftr *ftr = (struct crypt_mnt_ftr *) params; + + int N = 1 << ftr->N_factor; + int r = 1 << ftr->r_factor; + int p = 1 << ftr->p_factor; + + /* Turn the password into a key and IV that can decrypt the master key */ + unsigned int keysize; + unsigned char* master_key = convert_hex_ascii_to_key(passwd, &keysize); + if (!master_key) return -1; + crypto_scrypt(master_key, keysize, salt, SALT_LEN, N, r, p, ikey, + KEY_LEN_BYTES + IV_LEN_BYTES); + + memset(master_key, 0, keysize); + free (master_key); + return 0; +} + +static int scrypt_keymaster(const char *passwd, const unsigned char *salt, + unsigned char *ikey, void *params) +{ + printf("Using scrypt with keymaster for cryptfs KDF\n"); + + int rc; + unsigned int key_size; + size_t signature_size; + unsigned char* signature; + struct crypt_mnt_ftr *ftr = (struct crypt_mnt_ftr *) params; + + int N = 1 << ftr->N_factor; + int r = 1 << ftr->r_factor; + int p = 1 << ftr->p_factor; + + unsigned char* master_key = convert_hex_ascii_to_key(passwd, &key_size); + if (!master_key) { + printf("Failed to convert passwd from hex"); + return -1; + } + + rc = crypto_scrypt(master_key, key_size, salt, SALT_LEN, + N, r, p, ikey, KEY_LEN_BYTES + IV_LEN_BYTES); + memset(master_key, 0, key_size); + free(master_key); + + if (rc) { + printf("scrypt failed"); + return -1; + } + + if (keymaster_sign_object(ftr, ikey, KEY_LEN_BYTES + IV_LEN_BYTES, + &signature, &signature_size)) { + printf("Signing failed"); + return -1; + } + + rc = crypto_scrypt(signature, signature_size, salt, SALT_LEN, + N, r, p, ikey, KEY_LEN_BYTES + IV_LEN_BYTES); + free(signature); + + if (rc) { + printf("scrypt failed"); + return -1; + } + + return 0; +} + +static int encrypt_master_key(const char *passwd, const unsigned char *salt, + const unsigned char *decrypted_master_key, + unsigned char *encrypted_master_key, + struct crypt_mnt_ftr *crypt_ftr) +{ + 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; + int rc = 0; + + /* Turn the password into an intermediate key and IV that can decrypt the master key */ + get_device_scrypt_params(crypt_ftr); + + switch (crypt_ftr->kdf_type) { + case KDF_SCRYPT_KEYMASTER_UNPADDED: + case KDF_SCRYPT_KEYMASTER_BADLY_PADDED: + case KDF_SCRYPT_KEYMASTER: + if (keymaster_create_key(crypt_ftr)) { + printf("keymaster_create_key failed"); + return -1; + } + + if (scrypt_keymaster(passwd, salt, ikey, crypt_ftr)) { + printf("scrypt failed"); + return -1; + } + break; + + case KDF_SCRYPT: + if (scrypt(passwd, salt, ikey, crypt_ftr)) { + printf("scrypt failed"); + return -1; + } + break; + + default: + printf("Invalid kdf_type"); + return -1; + } + + /* Initialize the decryption engine */ + if (! EVP_EncryptInit(&e_ctx, EVP_aes_128_cbc(), ikey, ikey+KEY_LEN_BYTES)) { + printf("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)) { + printf("EVP_EncryptUpdate failed\n"); + return -1; + } + if (! EVP_EncryptFinal(&e_ctx, encrypted_master_key + encrypted_len, &final_len)) { + printf("EVP_EncryptFinal failed\n"); + return -1; + } + + if (encrypted_len + final_len != KEY_LEN_BYTES) { + printf("EVP_Encryption length check failed with %d, %d bytes\n", encrypted_len, final_len); + return -1; + } + + /* Store the scrypt of the intermediate key, so we can validate if it's a + password error or mount error when things go wrong. + Note there's no need to check for errors, since if this is incorrect, we + simply won't wipe userdata, which is the correct default behavior + */ + int N = 1 << crypt_ftr->N_factor; + int r = 1 << crypt_ftr->r_factor; + int p = 1 << crypt_ftr->p_factor; + + rc = crypto_scrypt(ikey, KEY_LEN_BYTES, + crypt_ftr->salt, sizeof(crypt_ftr->salt), N, r, p, + crypt_ftr->scrypted_intermediate_key, + sizeof(crypt_ftr->scrypted_intermediate_key)); + + if (rc) { + printf("encrypt_master_key: crypto_scrypt failed"); + } + + return 0; +} + +static int decrypt_master_key_aux(char *passwd, unsigned char *salt, + unsigned char *encrypted_master_key, + unsigned char *decrypted_master_key, + kdf_func kdf, void *kdf_params, + unsigned char** intermediate_key, + size_t* intermediate_key_size) +{ + 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 an intermediate key and IV that can decrypt the + master key */ + if (kdf(passwd, salt, ikey, kdf_params)) { + printf("kdf failed"); + return -1; + } + + /* 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; + } + + /* Copy intermediate key if needed by params */ + if (intermediate_key && intermediate_key_size) { + *intermediate_key = (unsigned char*) malloc(KEY_LEN_BYTES); + if (intermediate_key) { + memcpy(*intermediate_key, ikey, KEY_LEN_BYTES); + *intermediate_key_size = KEY_LEN_BYTES; + } + } + + return 0; +} + +static void get_kdf_func(struct crypt_mnt_ftr *ftr, kdf_func *kdf, void** kdf_params) +{ + if (ftr->kdf_type == KDF_SCRYPT_KEYMASTER_UNPADDED || + ftr->kdf_type == KDF_SCRYPT_KEYMASTER_BADLY_PADDED || + ftr->kdf_type == KDF_SCRYPT_KEYMASTER) { + *kdf = scrypt_keymaster; + *kdf_params = ftr; + } else if (ftr->kdf_type == KDF_SCRYPT) { + *kdf = scrypt; + *kdf_params = ftr; + } else { + *kdf = pbkdf2; + *kdf_params = NULL; + } +} + +static int decrypt_master_key(char *passwd, unsigned char *decrypted_master_key, + struct crypt_mnt_ftr *crypt_ftr, + unsigned char** intermediate_key, + size_t* intermediate_key_size) +{ + kdf_func kdf; + void *kdf_params; + int ret; + + get_kdf_func(crypt_ftr, &kdf, &kdf_params); + ret = decrypt_master_key_aux(passwd, crypt_ftr->salt, crypt_ftr->master_key, + decrypted_master_key, kdf, kdf_params, + intermediate_key, intermediate_key_size); + if (ret != 0) { + printf("failure decrypting master key"); + } + + return ret; +} + +static int create_encrypted_random_key(char *passwd, unsigned char *master_key, unsigned char *salt, + struct crypt_mnt_ftr *crypt_ftr) { + 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, crypt_ftr); +} + +static int wait_and_unmount(char *mountpoint, bool kill) +{ + int i, err, rc; +#define WAIT_UNMOUNT_COUNT 20 + + /* Now umount the tmpfs filesystem */ + for (i=0; i 0 && atoi(ro_prop)) { + struct fstab_rec* rec = fs_mgr_get_entry_for_mount_point(fstab, DATA_MNT_POINT); + rec->flags |= MS_RDONLY; + } + + /* If that succeeded, then mount the decrypted filesystem */ + int retries = RETRY_MOUNT_ATTEMPTS; + int mount_rc; + while ((mount_rc = fs_mgr_do_mount(fstab, DATA_MNT_POINT, + crypto_blkdev, 0)) + != 0) { + if (mount_rc == FS_MGR_DOMNT_BUSY) { + /* TODO: invoke something similar to + Process::killProcessWithOpenFiles(DATA_MNT_POINT, + retries > RETRY_MOUNT_ATTEMPT/2 ? 1 : 2 ) */ + printf("Failed to mount %s because it is busy - waiting", + crypto_blkdev); + if (--retries) { + sleep(RETRY_MOUNT_DELAY_SECONDS); + } else { + /* Let's hope that a reboot clears away whatever is keeping + the mount busy */ + cryptfs_reboot(reboot); + } + } else { + printf("Failed to mount decrypted data"); + cryptfs_set_corrupt(); + cryptfs_trigger_restart_min_framework(); + printf("Started framework to offer wipe"); + return -1; + } + } + + 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"); + printf("Just triggered restart_framework\n"); + + /* Give it a few moments to get started */ + sleep(1); + } + + if (rc == 0) { + restart_successful = 1; + } + + return rc; +} + +int cryptfs_restart(void) +{ + /* Call internal implementation forcing a restart of main service group */ + return cryptfs_restart_internal(1); +} + +static int do_crypto_complete(char *mount_point UNUSED) +{ + struct crypt_mnt_ftr crypt_ftr; + char encrypted_state[PROPERTY_VALUE_MAX]; + char key_loc[PROPERTY_VALUE_MAX]; + + property_get("ro.crypto.state", encrypted_state, ""); + if (strcmp(encrypted_state, "encrypted") ) { + printf("not running with encryption, aborting"); + return CRYPTO_COMPLETE_NOT_ENCRYPTED; + } + + if (get_crypt_ftr_and_key(&crypt_ftr)) { + fs_mgr_get_crypt_info(fstab, key_loc, 0, sizeof(key_loc)); + + /* + * Only report this error if key_loc is a file and it exists. + * If the device was never encrypted, and /data is not mountable for + * some reason, returning 1 should prevent the UI from presenting the + * a "enter password" screen, or worse, a "press button to wipe the + * device" screen. + */ + if ((key_loc[0] == '/') && (access("key_loc", F_OK) == -1)) { + printf("master key file does not exist, aborting"); + return CRYPTO_COMPLETE_NOT_ENCRYPTED; + } else { + printf("Error getting crypt footer and key\n"); + return CRYPTO_COMPLETE_BAD_METADATA; + } + } + + // Test for possible error flags + if (crypt_ftr.flags & CRYPT_ENCRYPTION_IN_PROGRESS){ + printf("Encryption process is partway completed\n"); + return CRYPTO_COMPLETE_PARTIAL; + } + + if (crypt_ftr.flags & CRYPT_INCONSISTENT_STATE){ + printf("Encryption process was interrupted but cannot continue\n"); + return CRYPTO_COMPLETE_INCONSISTENT; + } + + if (crypt_ftr.flags & CRYPT_DATA_CORRUPT){ + printf("Encryption is successful but data is corrupt\n"); + return CRYPTO_COMPLETE_CORRUPT; + } + + /* We passed the test! We shall diminish, and return to the west */ + return CRYPTO_COMPLETE_ENCRYPTED; +} + +static int test_mount_encrypted_fs(struct crypt_mnt_ftr* crypt_ftr, + char *passwd, char *mount_point, char *label) +{ + /* Allocate enough space for a 256 bit key, but we may use less */ + unsigned char decrypted_master_key[32]; + char crypto_blkdev[MAXPATHLEN]; + char real_blkdev[MAXPATHLEN]; + char tmp_mount_point[64]; + unsigned int orig_failed_decrypt_count; + int rc; + kdf_func kdf; + void *kdf_params; + int use_keymaster = 0; + int upgrade = 0; + unsigned char* intermediate_key = 0; + size_t intermediate_key_size = 0; + + 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) ) { + if (decrypt_master_key(passwd, decrypted_master_key, crypt_ftr, + &intermediate_key, &intermediate_key_size)) { + printf("Failed to decrypt master key\n"); + rc = -1; + goto errout; + } + } + + fs_mgr_get_crypt_info(fstab, 0, real_blkdev, sizeof(real_blkdev)); + + // Create crypto block device - all (non fatal) code paths + // need it + if (create_crypto_blk_dev(crypt_ftr, decrypted_master_key, + real_blkdev, crypto_blkdev, label)) { + printf("Error creating decrypted block device\n"); + rc = -1; + goto errout; + } + + /* Work out if the problem is the password or the data */ + unsigned char scrypted_intermediate_key[sizeof(crypt_ftr-> + scrypted_intermediate_key)]; + int N = 1 << crypt_ftr->N_factor; + int r = 1 << crypt_ftr->r_factor; + int p = 1 << crypt_ftr->p_factor; + + rc = crypto_scrypt(intermediate_key, intermediate_key_size, + crypt_ftr->salt, sizeof(crypt_ftr->salt), + N, r, p, scrypted_intermediate_key, + sizeof(scrypted_intermediate_key)); + + // Does the key match the crypto footer? + if (rc == 0 && memcmp(scrypted_intermediate_key, + crypt_ftr->scrypted_intermediate_key, + sizeof(scrypted_intermediate_key)) == 0) { + printf("Password matches\n"); + rc = 0; + } else { + /* Try mounting the file system anyway, just in case the problem's with + * the footer, not the key. */ + sprintf(tmp_mount_point, "%s/tmp_mnt", mount_point); + mkdir(tmp_mount_point, 0755); + if (fs_mgr_do_mount(fstab, DATA_MNT_POINT, crypto_blkdev, tmp_mount_point)) { + printf("Error temp mounting decrypted block device '%s'\n", crypto_blkdev); + delete_crypto_blk_dev(label); + + rc = ++crypt_ftr->failed_decrypt_count; + //put_crypt_ftr_and_key(crypt_ftr); // Do not penalize for attempting to decrypt in recovery + } else { + /* Success! */ + printf("Password did not match but decrypted drive mounted - continue\n"); + umount(tmp_mount_point); + rc = 0; + } + } + + if (rc == 0) { + /*crypt_ftr->failed_decrypt_count = 0; + if (orig_failed_decrypt_count != 0) { + put_crypt_ftr_and_key(crypt_ftr); + }*/ + + /* 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_mount_point = strdup(mount_point); + master_key_saved = 1; + printf("%s(): Master key saved\n", __FUNCTION__);*/ + rc = 0; + + // Upgrade if we're not using the latest KDF. + /*use_keymaster = keymaster_check_compatibility(); + if (crypt_ftr->kdf_type == KDF_SCRYPT_KEYMASTER) { + // Don't allow downgrade + } else if (use_keymaster == 1 && crypt_ftr->kdf_type != KDF_SCRYPT_KEYMASTER) { + crypt_ftr->kdf_type = KDF_SCRYPT_KEYMASTER; + upgrade = 1; + } else if (use_keymaster == 0 && crypt_ftr->kdf_type != KDF_SCRYPT) { + crypt_ftr->kdf_type = KDF_SCRYPT; + upgrade = 1; + } + + if (upgrade) { + rc = encrypt_master_key(passwd, crypt_ftr->salt, saved_master_key, + crypt_ftr->master_key, crypt_ftr); + if (!rc) { + rc = put_crypt_ftr_and_key(crypt_ftr); + } + printf("Key Derivation Function upgrade: rc=%d\n", rc); + + // Do not fail even if upgrade failed - machine is bootable + // Note that if this code is ever hit, there is a *serious* problem + // since KDFs should never fail. You *must* fix the kdf before + // proceeding! + if (rc) { + printf("Upgrade failed with error %d," + " but continuing with previous state\n", + rc); + rc = 0; + } + }*/ + } + + errout: + if (intermediate_key) { + memset(intermediate_key, 0, intermediate_key_size); + free(intermediate_key); + } + 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; + struct stat statbuf; + int nr_sec, fd; + + sprintf(real_blkdev, "/dev/block/vold/%d:%d", major, minor); + + get_crypt_ftr_and_key(&sd_crypt_ftr); + + /* 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) { + printf("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 check_unmounted_and_get_ftr(struct crypt_mnt_ftr* crypt_ftr) +{ + char encrypted_state[PROPERTY_VALUE_MAX]; + 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"); + return -1; + } + + if (get_crypt_ftr_and_key(crypt_ftr)) { + printf("Error getting crypt footer and key"); + return -1; + } + + return 0; +} + +/* + * TODO - transition patterns to new format in calling code + * and remove this vile hack, and the use of hex in + * the password passing code. + * + * Patterns are passed in zero based (i.e. the top left dot + * is represented by zero, the top middle one etc), but we want + * to store them '1' based. + * This is to allow us to migrate the calling code to use this + * convention. It also solves a nasty problem whereby scrypt ignores + * trailing zeros, so patterns ending at the top left could be + * truncated, and similarly, you could add the top left to any + * pattern and still match. + * adjust_passwd is a hack function that returns the alternate representation + * if the password appears to be a pattern (hex numbers all less than 09) + * If it succeeds we need to try both, and in particular try the alternate + * first. If the original matches, then we need to update the footer + * with the alternate. + * All code that accepts passwords must adjust them first. Since + * cryptfs_check_passwd is always the first function called after a migration + * (and indeed on any boot) we only need to do the double try in this + * function. + */ +char* adjust_passwd(const char* passwd) +{ + size_t index, length; + + if (!passwd) { + return 0; + } + + // Check even length. Hex encoded passwords are always + // an even length, since each character encodes to two characters. + length = strlen(passwd); + if (length % 2) { + printf("Password not correctly hex encoded."); + return 0; + } + + // Check password is old-style pattern - a collection of hex + // encoded bytes less than 9 (00 through 08) + for (index = 0; index < length; index +=2) { + if (passwd[index] != '0' + || passwd[index + 1] < '0' || passwd[index + 1] > '8') { + return 0; + } + } + + // Allocate room for adjusted passwd and null terminate + char* adjusted = malloc(length + 1); + adjusted[length] = 0; + + // Add 0x31 ('1') to each character + for (index = 0; index < length; index += 2) { + // output is 31 through 39 so set first byte to three, second to src + 1 + adjusted[index] = '3'; + adjusted[index + 1] = passwd[index + 1] + 1; + } + + return adjusted; +} + +/* + * Passwords in L get passed from Android to cryptfs in hex, so a '1' + * gets converted to '31' where 31 is 0x31 which is the ascii character + * code in hex of the character '1'. This function will convert the + * regular character codes to their hexadecimal representation to make + * decrypt work properly with Android 5.0 lollipop decryption. + */ +char* hexadj_passwd(const char* passwd) +{ + size_t index, length; + char* ptr = passwd; + + if (!passwd) { + return 0; + } + + length = strlen(passwd); + + // Allocate room for hex passwd and null terminate + char* hex = malloc((length * 2) + 1); + hex[length * 2] = 0; + + // Convert to hex + for (index = 0; index < length; index++) { + sprintf(hex + (index * 2), "%02X", *ptr); + ptr++; + } + + return hex; +} + +#define FSTAB_PREFIX "/fstab." + +int cryptfs_check_footer(void) +{ + int rc = -1; + char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)]; + char propbuf[PROPERTY_VALUE_MAX]; + struct crypt_mnt_ftr crypt_ftr; + + property_get("ro.hardware", propbuf, ""); + snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf); + + fstab = fs_mgr_read_fstab(fstab_filename); + if (!fstab) { + printf("failed to open %s\n", fstab_filename); + return -1; + } + + rc = get_crypt_ftr_and_key(&crypt_ftr); + + return rc; +} + +int cryptfs_check_passwd(char *passwd) +{ + struct crypt_mnt_ftr crypt_ftr; + int rc; + char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)]; + char propbuf[PROPERTY_VALUE_MAX]; + + property_get("ro.hardware", propbuf, ""); + snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf); + + fstab = fs_mgr_read_fstab(fstab_filename); + if (!fstab) { + printf("failed to open %s\n", fstab_filename); + return -1; + } + + rc = check_unmounted_and_get_ftr(&crypt_ftr); + if (rc) + return rc; + + char* adjusted_passwd = adjust_passwd(passwd); + char* hex_passwd = hexadj_passwd(passwd); + + if (adjusted_passwd) { + int failed_decrypt_count = crypt_ftr.failed_decrypt_count; + rc = test_mount_encrypted_fs(&crypt_ftr, adjusted_passwd, + DATA_MNT_POINT, "userdata"); + + // Maybe the original one still works? + if (rc) { + // Don't double count this failure + crypt_ftr.failed_decrypt_count = failed_decrypt_count; + rc = test_mount_encrypted_fs(&crypt_ftr, passwd, + DATA_MNT_POINT, "userdata"); + if (!rc) { + // cryptfs_changepw also adjusts so pass original + // Note that adjust_passwd only recognises patterns + // so we can safely use CRYPT_TYPE_PATTERN + printf("TWRP NOT Updating pattern to new format"); + //cryptfs_changepw(CRYPT_TYPE_PATTERN, passwd); + } else if (hex_passwd) { + rc = test_mount_encrypted_fs(&crypt_ftr, hex_passwd, + DATA_MNT_POINT, "userdata"); + } + } + free(adjusted_passwd); + } else { + rc = test_mount_encrypted_fs(&crypt_ftr, passwd, + DATA_MNT_POINT, "userdata"); + if (rc && hex_passwd) { + rc = test_mount_encrypted_fs(&crypt_ftr, hex_passwd, + DATA_MNT_POINT, "userdata"); + } + } + + if (hex_passwd) + free(hex_passwd); + + /*if (rc == 0 && crypt_ftr.crypt_type != CRYPT_TYPE_DEFAULT) { + printf("cryptfs_check_passwd update expiry time?\n"); + cryptfs_clear_password(); + password = strdup(passwd); + struct timespec now; + clock_gettime(CLOCK_BOOTTIME, &now); + password_expiry_time = now.tv_sec + password_max_age_seconds; + }*/ + + 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 decrypted_master_key[32]; + char encrypted_state[PROPERTY_VALUE_MAX]; + int rc; + + property_get("ro.crypto.state", encrypted_state, ""); + if (strcmp(encrypted_state, "encrypted") ) { + printf("device not encrypted, aborting"); + return -2; + } + + if (!master_key_saved) { + printf("encrypted fs not yet mounted, aborting"); + return -1; + } + + if (!saved_mount_point) { + printf("encrypted fs failed to save mount point, aborting"); + return -1; + } + + if (get_crypt_ftr_and_key(&crypt_ftr)) { + printf("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 { + char* adjusted_passwd = adjust_passwd(passwd); + if (adjusted_passwd) { + passwd = adjusted_passwd; + } + + decrypt_master_key(passwd, decrypted_master_key, &crypt_ftr, 0, 0); + 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; + } + + free(adjusted_passwd); + } + + 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 int cryptfs_init_crypt_mnt_ftr(struct crypt_mnt_ftr *ftr) +{ + off64_t off; + + memset(ftr, 0, sizeof(struct crypt_mnt_ftr)); + ftr->magic = CRYPT_MNT_MAGIC; + ftr->major_version = CURRENT_MAJOR_VERSION; + ftr->minor_version = CURRENT_MINOR_VERSION; + ftr->ftr_size = sizeof(struct crypt_mnt_ftr); + ftr->keysize = KEY_LEN_BYTES; + + switch (keymaster_check_compatibility()) { + case 1: + ftr->kdf_type = KDF_SCRYPT_KEYMASTER; + break; + + case 0: + ftr->kdf_type = KDF_SCRYPT; + break; + + default: + printf("keymaster_check_compatibility failed"); + return -1; + } + + get_device_scrypt_params(ftr); + + ftr->persist_data_size = CRYPT_PERSIST_DATA_SIZE; + if (get_crypt_ftr_info(NULL, &off) == 0) { + ftr->persist_data_offset[0] = off + CRYPT_FOOTER_TO_PERSIST_OFFSET; + ftr->persist_data_offset[1] = off + CRYPT_FOOTER_TO_PERSIST_OFFSET + + ftr->persist_data_size; + } + + return 0; +} + +static int cryptfs_enable_wipe(char *crypto_blkdev, off64_t size, int type) +{ + const char *args[10]; + char size_str[32]; /* Must be large enough to hold a %lld and null byte */ + int num_args; + int status; + int tmp; + int rc = -1; + + if (type == EXT4_FS) { + args[0] = "/system/bin/make_ext4fs"; + args[1] = "-a"; + args[2] = "/data"; + args[3] = "-l"; + snprintf(size_str, sizeof(size_str), "%" PRId64, size * 512); + args[4] = size_str; + args[5] = crypto_blkdev; + num_args = 6; + printf("Making empty filesystem with command %s %s %s %s %s %s\n", + args[0], args[1], args[2], args[3], args[4], args[5]); + } else if (type == F2FS_FS) { + args[0] = "/system/bin/mkfs.f2fs"; + args[1] = "-t"; + args[2] = "-d1"; + args[3] = crypto_blkdev; + snprintf(size_str, sizeof(size_str), "%" PRId64, size); + args[4] = size_str; + num_args = 5; + printf("Making empty filesystem with command %s %s %s %s %s\n", + args[0], args[1], args[2], args[3], args[4]); + } else { + printf("cryptfs_enable_wipe(): unknown filesystem type %d\n", type); + return -1; + } + + tmp = android_fork_execvp(num_args, (char **)args, &status, false, true); + + if (tmp != 0) { + printf("Error creating empty filesystem on %s due to logwrap error\n", crypto_blkdev); + } else { + if (WIFEXITED(status)) { + if (WEXITSTATUS(status)) { + printf("Error creating filesystem on %s, exit status %d ", + crypto_blkdev, WEXITSTATUS(status)); + } else { + printf("Successfully created filesystem on %s\n", crypto_blkdev); + rc = 0; + } + } else { + printf("Error creating filesystem on %s, did not exit normally\n", crypto_blkdev); + } + } + + return rc; +} + +#define CRYPT_INPLACE_BUFSIZE 4096 +#define CRYPT_SECTORS_PER_BUFSIZE (CRYPT_INPLACE_BUFSIZE / CRYPT_SECTOR_SIZE) +#define CRYPT_SECTOR_SIZE 512 + +/* aligned 32K writes tends to make flash happy. + * SD card association recommends it. + */ +#define BLOCKS_AT_A_TIME 8 + +struct encryptGroupsData +{ + int realfd; + int cryptofd; + off64_t numblocks; + off64_t one_pct, cur_pct, new_pct; + off64_t blocks_already_done, tot_numblocks; + off64_t used_blocks_already_done, tot_used_blocks; + char* real_blkdev, * crypto_blkdev; + int count; + off64_t offset; + char* buffer; + off64_t last_written_sector; + int completed; + time_t time_started; + int remaining_time; +}; + +static void update_progress(struct encryptGroupsData* data, int is_used) +{ + data->blocks_already_done++; + + if (is_used) { + data->used_blocks_already_done++; + } + if (data->tot_used_blocks) { + data->new_pct = data->used_blocks_already_done / data->one_pct; + } else { + data->new_pct = data->blocks_already_done / data->one_pct; + } + + if (data->new_pct > data->cur_pct) { + char buf[8]; + data->cur_pct = data->new_pct; + snprintf(buf, sizeof(buf), "%" PRId64, data->cur_pct); + property_set("vold.encrypt_progress", buf); + } + + if (data->cur_pct >= 5) { + struct timespec time_now; + if (clock_gettime(CLOCK_MONOTONIC, &time_now)) { + printf("Error getting time"); + } else { + double elapsed_time = difftime(time_now.tv_sec, data->time_started); + off64_t remaining_blocks = data->tot_used_blocks + - data->used_blocks_already_done; + int remaining_time = (int)(elapsed_time * remaining_blocks + / data->used_blocks_already_done); + + // Change time only if not yet set, lower, or a lot higher for + // best user experience + if (data->remaining_time == -1 + || remaining_time < data->remaining_time + || remaining_time > data->remaining_time + 60) { + char buf[8]; + snprintf(buf, sizeof(buf), "%d", remaining_time); + property_set("vold.encrypt_time_remaining", buf); + data->remaining_time = remaining_time; + } + } + } +} + +static void log_progress(struct encryptGroupsData const* data, bool completed) +{ + // Precondition - if completed data = 0 else data != 0 + + // Track progress so we can skip logging blocks + static off64_t offset = -1; + + // Need to close existing 'Encrypting from' log? + if (completed || (offset != -1 && data->offset != offset)) { + printf("Encrypted to sector %" PRId64, + offset / info.block_size * CRYPT_SECTOR_SIZE); + offset = -1; + } + + // Need to start new 'Encrypting from' log? + if (!completed && offset != data->offset) { + printf("Encrypting from sector %" PRId64, + data->offset / info.block_size * CRYPT_SECTOR_SIZE); + } + + // Update offset + if (!completed) { + offset = data->offset + (off64_t)data->count * info.block_size; + } +} + +static int flush_outstanding_data(struct encryptGroupsData* data) +{ + if (data->count == 0) { + return 0; + } + + printf("Copying %d blocks at offset %" PRIx64, data->count, data->offset); + + if (pread64(data->realfd, data->buffer, + info.block_size * data->count, data->offset) + <= 0) { + printf("Error reading real_blkdev %s for inplace encrypt", + data->real_blkdev); + return -1; + } + + if (pwrite64(data->cryptofd, data->buffer, + info.block_size * data->count, data->offset) + <= 0) { + printf("Error writing crypto_blkdev %s for inplace encrypt", + data->crypto_blkdev); + return -1; + } else { + log_progress(data, false); + } + + data->count = 0; + data->last_written_sector = (data->offset + data->count) + / info.block_size * CRYPT_SECTOR_SIZE - 1; + return 0; +} + +static int encrypt_groups(struct encryptGroupsData* data) +{ + unsigned int i; + u8 *block_bitmap = 0; + unsigned int block; + off64_t ret; + int rc = -1; + + data->buffer = malloc(info.block_size * BLOCKS_AT_A_TIME); + if (!data->buffer) { + printf("Failed to allocate crypto buffer"); + goto errout; + } + + block_bitmap = malloc(info.block_size); + if (!block_bitmap) { + printf("failed to allocate block bitmap"); + goto errout; + } + + for (i = 0; i < aux_info.groups; ++i) { + printf("Encrypting group %d", i); + + u32 first_block = aux_info.first_data_block + i * info.blocks_per_group; + u32 block_count = min(info.blocks_per_group, + aux_info.len_blocks - first_block); + + off64_t offset = (u64)info.block_size + * aux_info.bg_desc[i].bg_block_bitmap; + + ret = pread64(data->realfd, block_bitmap, info.block_size, offset); + if (ret != (int)info.block_size) { + printf("failed to read all of block group bitmap %d", i); + goto errout; + } + + offset = (u64)info.block_size * first_block; + + data->count = 0; + + for (block = 0; block < block_count; block++) { + int used = bitmap_get_bit(block_bitmap, block); + update_progress(data, used); + if (used) { + if (data->count == 0) { + data->offset = offset; + } + data->count++; + } else { + if (flush_outstanding_data(data)) { + goto errout; + } + } + + offset += info.block_size; + + /* Write data if we are aligned or buffer size reached */ + if (offset % (info.block_size * BLOCKS_AT_A_TIME) == 0 + || data->count == BLOCKS_AT_A_TIME) { + if (flush_outstanding_data(data)) { + goto errout; + } + } + + if (1) { + printf("Stopping encryption due to low battery"); + rc = 0; + goto errout; + } + + } + if (flush_outstanding_data(data)) { + goto errout; + } + } + + data->completed = 1; + rc = 0; + +errout: + log_progress(0, true); + free(data->buffer); + free(block_bitmap); + return rc; +} + +static int cryptfs_enable_inplace_ext4(char *crypto_blkdev, + char *real_blkdev, + off64_t size, + off64_t *size_already_done, + off64_t tot_size, + off64_t previously_encrypted_upto) +{ + u32 i; + struct encryptGroupsData data; + int rc; // Can't initialize without causing warning -Wclobbered + + if (previously_encrypted_upto > *size_already_done) { + printf("Not fast encrypting since resuming part way through"); + return -1; + } + + memset(&data, 0, sizeof(data)); + data.real_blkdev = real_blkdev; + data.crypto_blkdev = crypto_blkdev; + + if ( (data.realfd = open(real_blkdev, O_RDWR)) < 0) { + printf("Error opening real_blkdev %s for inplace encrypt. err=%d(%s)\n", + real_blkdev, errno, strerror(errno)); + rc = -1; + goto errout; + } + + if ( (data.cryptofd = open(crypto_blkdev, O_WRONLY)) < 0) { + printf("Error opening crypto_blkdev %s for ext4 inplace encrypt. err=%d(%s)\n", + crypto_blkdev, errno, strerror(errno)); + rc = ENABLE_INPLACE_ERR_DEV; + goto errout; + } + + if (setjmp(setjmp_env)) { + printf("Reading ext4 extent caused an exception\n"); + rc = -1; + goto errout; + } + + if (read_ext(data.realfd, 0) != 0) { + printf("Failed to read ext4 extent\n"); + rc = -1; + goto errout; + } + + data.numblocks = size / CRYPT_SECTORS_PER_BUFSIZE; + data.tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE; + data.blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE; + + printf("Encrypting ext4 filesystem in place..."); + + data.tot_used_blocks = data.numblocks; + for (i = 0; i < aux_info.groups; ++i) { + data.tot_used_blocks -= aux_info.bg_desc[i].bg_free_blocks_count; + } + + data.one_pct = data.tot_used_blocks / 100; + data.cur_pct = 0; + + struct timespec time_started = {0}; + if (clock_gettime(CLOCK_MONOTONIC, &time_started)) { + printf("Error getting time at start"); + // Note - continue anyway - we'll run with 0 + } + data.time_started = time_started.tv_sec; + data.remaining_time = -1; + + rc = encrypt_groups(&data); + if (rc) { + printf("Error encrypting groups"); + goto errout; + } + + *size_already_done += data.completed ? size : data.last_written_sector; + rc = 0; + +errout: + close(data.realfd); + close(data.cryptofd); + + return rc; +} + +static void log_progress_f2fs(u64 block, bool completed) +{ + // Precondition - if completed data = 0 else data != 0 + + // Track progress so we can skip logging blocks + static u64 last_block = (u64)-1; + + // Need to close existing 'Encrypting from' log? + if (completed || (last_block != (u64)-1 && block != last_block + 1)) { + printf("Encrypted to block %" PRId64, last_block); + last_block = -1; + } + + // Need to start new 'Encrypting from' log? + if (!completed && (last_block == (u64)-1 || block != last_block + 1)) { + printf("Encrypting from block %" PRId64, block); + } + + // Update offset + if (!completed) { + last_block = block; + } +} + +static int encrypt_one_block_f2fs(u64 pos, void *data) +{ + struct encryptGroupsData *priv_dat = (struct encryptGroupsData *)data; + + priv_dat->blocks_already_done = pos - 1; + update_progress(priv_dat, 1); + + off64_t offset = pos * CRYPT_INPLACE_BUFSIZE; + + if (pread64(priv_dat->realfd, priv_dat->buffer, CRYPT_INPLACE_BUFSIZE, offset) <= 0) { + printf("Error reading real_blkdev %s for f2fs inplace encrypt", priv_dat->crypto_blkdev); + return -1; + } + + if (pwrite64(priv_dat->cryptofd, priv_dat->buffer, CRYPT_INPLACE_BUFSIZE, offset) <= 0) { + printf("Error writing crypto_blkdev %s for f2fs inplace encrypt", priv_dat->crypto_blkdev); + return -1; + } else { + log_progress_f2fs(pos, false); + } + + return 0; +} + +static int cryptfs_enable_inplace_f2fs(char *crypto_blkdev, + char *real_blkdev, + off64_t size, + off64_t *size_already_done, + off64_t tot_size, + off64_t previously_encrypted_upto) +{ + u32 i; + struct encryptGroupsData data; + struct f2fs_info *f2fs_info = NULL; + int rc = ENABLE_INPLACE_ERR_OTHER; + if (previously_encrypted_upto > *size_already_done) { + printf("Not fast encrypting since resuming part way through"); + return ENABLE_INPLACE_ERR_OTHER; + } + memset(&data, 0, sizeof(data)); + data.real_blkdev = real_blkdev; + data.crypto_blkdev = crypto_blkdev; + data.realfd = -1; + data.cryptofd = -1; + if ( (data.realfd = open64(real_blkdev, O_RDWR)) < 0) { + printf("Error opening real_blkdev %s for f2fs inplace encrypt\n", + real_blkdev); + goto errout; + } + if ( (data.cryptofd = open64(crypto_blkdev, O_WRONLY)) < 0) { + printf("Error opening crypto_blkdev %s for f2fs inplace encrypt. err=%d(%s)\n", + crypto_blkdev, errno, strerror(errno)); + rc = ENABLE_INPLACE_ERR_DEV; + goto errout; + } + + f2fs_info = generate_f2fs_info(data.realfd); + if (!f2fs_info) + goto errout; + + data.numblocks = size / CRYPT_SECTORS_PER_BUFSIZE; + data.tot_numblocks = tot_size / CRYPT_SECTORS_PER_BUFSIZE; + data.blocks_already_done = *size_already_done / CRYPT_SECTORS_PER_BUFSIZE; + + data.tot_used_blocks = get_num_blocks_used(f2fs_info); + + data.one_pct = data.tot_used_blocks / 100; + data.cur_pct = 0; + data.time_started = time(NULL); + data.remaining_time = -1; + + data.buffer = malloc(f2fs_info->block_size); + if (!data.buffer) { + printf("Failed to allocate crypto buffer"); + goto errout; + } + + data.count = 0; + + /* Currently, this either runs to completion, or hits a nonrecoverable error */ + rc = run_on_used_blocks(data.blocks_already_done, f2fs_info, &encrypt_one_block_f2fs, &data); + + if (rc) { + printf("Error in running over f2fs blocks"); + rc = ENABLE_INPLACE_ERR_OTHER; + goto errout; + } + + *size_already_done += size; + rc = 0; + +errout: + if (rc) + printf("Failed to encrypt f2fs filesystem on %s", real_blkdev); + + log_progress_f2fs(0, true); + free(f2fs_info); + free(data.buffer); + close(data.realfd); + close(data.cryptofd); + + return rc; +} + +static int cryptfs_enable_inplace_full(char *crypto_blkdev, char *real_blkdev, + off64_t size, off64_t *size_already_done, + off64_t tot_size, + off64_t previously_encrypted_upto) +{ + int realfd, cryptofd; + char *buf[CRYPT_INPLACE_BUFSIZE]; + int rc = ENABLE_INPLACE_ERR_OTHER; + 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) { + printf("Error opening real_blkdev %s for inplace encrypt\n", real_blkdev); + return ENABLE_INPLACE_ERR_OTHER; + } + + if ( (cryptofd = open(crypto_blkdev, O_WRONLY)) < 0) { + printf("Error opening crypto_blkdev %s for inplace encrypt. err=%d(%s)\n", + crypto_blkdev, errno, strerror(errno)); + close(realfd); + return ENABLE_INPLACE_ERR_DEV; + } + + /* 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; + + printf("Encrypting filesystem in place..."); + + i = previously_encrypted_upto + 1 - *size_already_done; + + if (lseek64(realfd, i * CRYPT_SECTOR_SIZE, SEEK_SET) < 0) { + printf("Cannot seek to previously encrypted point on %s", real_blkdev); + goto errout; + } + + if (lseek64(cryptofd, i * CRYPT_SECTOR_SIZE, SEEK_SET) < 0) { + printf("Cannot seek to previously encrypted point on %s", crypto_blkdev); + goto errout; + } + + for (;i < size && i % CRYPT_SECTORS_PER_BUFSIZE != 0; ++i) { + if (unix_read(realfd, buf, CRYPT_SECTOR_SIZE) <= 0) { + printf("Error reading initial sectors from real_blkdev %s for " + "inplace encrypt\n", crypto_blkdev); + goto errout; + } + if (unix_write(cryptofd, buf, CRYPT_SECTOR_SIZE) <= 0) { + printf("Error writing initial sectors to crypto_blkdev %s for " + "inplace encrypt\n", crypto_blkdev); + goto errout; + } else { + printf("Encrypted 1 block at %" PRId64, i); + } + } + + one_pct = tot_numblocks / 100; + cur_pct = 0; + /* process the majority of the filesystem in blocks */ + for (i/=CRYPT_SECTORS_PER_BUFSIZE; i cur_pct) { + char buf[8]; + + cur_pct = new_pct; + snprintf(buf, sizeof(buf), "%" PRId64, cur_pct); + property_set("vold.encrypt_progress", buf); + } + if (unix_read(realfd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) { + printf("Error reading real_blkdev %s for inplace encrypt", crypto_blkdev); + goto errout; + } + if (unix_write(cryptofd, buf, CRYPT_INPLACE_BUFSIZE) <= 0) { + printf("Error writing crypto_blkdev %s for inplace encrypt", crypto_blkdev); + goto errout; + } else { + printf("Encrypted %d block at %" PRId64, + CRYPT_SECTORS_PER_BUFSIZE, + i * CRYPT_SECTORS_PER_BUFSIZE); + } + + if (1) { + printf("Stopping encryption due to low battery"); + *size_already_done += (i + 1) * CRYPT_SECTORS_PER_BUFSIZE - 1; + rc = 0; + goto errout; + } + } + + /* Do any remaining sectors */ + for (i=0; iflags & (VOL_ENCRYPTABLE | VOL_NONREMOVABLE)) == + (VOL_ENCRYPTABLE | VOL_NONREMOVABLE); +} + +static int cryptfs_SHA256_fileblock(const char* filename, __le8* buf) +{ + int fd = open(filename, O_RDONLY); + if (fd == -1) { + printf("Error opening file %s", filename); + return -1; + } + + char block[CRYPT_INPLACE_BUFSIZE]; + memset(block, 0, sizeof(block)); + if (unix_read(fd, block, sizeof(block)) < 0) { + printf("Error reading file %s", filename); + close(fd); + return -1; + } + + close(fd); + + SHA256_CTX c; + SHA256_Init(&c); + SHA256_Update(&c, block, sizeof(block)); + SHA256_Final(buf, &c); + + return 0; +} + +static int get_fs_type(struct fstab_rec *rec) +{ + if (!strcmp(rec->fs_type, "ext4")) { + return EXT4_FS; + } else if (!strcmp(rec->fs_type, "f2fs")) { + return F2FS_FS; + } else { + return -1; + } +} + +static int cryptfs_enable_all_volumes(struct crypt_mnt_ftr *crypt_ftr, int how, + char *crypto_blkdev, char *real_blkdev, + int previously_encrypted_upto) +{ + off64_t cur_encryption_done=0, tot_encryption_size=0; + int i, rc = -1; + + if (1) { + printf("Not starting encryption due to low battery"); + return 0; + } + + /* The size of the userdata partition, and add in the vold volumes below */ + tot_encryption_size = crypt_ftr->fs_size; + + if (how == CRYPTO_ENABLE_WIPE) { + struct fstab_rec* rec = fs_mgr_get_entry_for_mount_point(fstab, DATA_MNT_POINT); + int fs_type = get_fs_type(rec); + if (fs_type < 0) { + printf("cryptfs_enable: unsupported fs type %s\n", rec->fs_type); + return -1; + } + rc = cryptfs_enable_wipe(crypto_blkdev, crypt_ftr->fs_size, fs_type); + } else if (how == CRYPTO_ENABLE_INPLACE) { + rc = cryptfs_enable_inplace(crypto_blkdev, real_blkdev, + crypt_ftr->fs_size, &cur_encryption_done, + tot_encryption_size, + previously_encrypted_upto); + + if (rc == ENABLE_INPLACE_ERR_DEV) { + /* Hack for b/17898962 */ + printf("cryptfs_enable: crypto block dev failure. Must reboot...\n"); + cryptfs_reboot(reboot); + } + + if (!rc) { + crypt_ftr->encrypted_upto = cur_encryption_done; + } + + if (!rc && crypt_ftr->encrypted_upto == crypt_ftr->fs_size) { + /* The inplace routine never actually sets the progress to 100% due + * to the round down nature of integer division, so set it here */ + property_set("vold.encrypt_progress", "100"); + } + } else { + /* Shouldn't happen */ + printf("cryptfs_enable: internal error, unknown option\n"); + rc = -1; + } + + return rc; +} + +int cryptfs_enable_internal(char *howarg, int crypt_type, char *passwd, + int allow_reboot) +{ + int how = 0; + char crypto_blkdev[MAXPATHLEN], real_blkdev[MAXPATHLEN]; + unsigned long nr_sec; + unsigned char decrypted_master_key[KEY_LEN_BYTES]; + int rc=-1, fd, i, ret; + struct crypt_mnt_ftr crypt_ftr; + struct crypt_persist_data *pdata; + char encrypted_state[PROPERTY_VALUE_MAX]; + char lockid[32] = { 0 }; + char key_loc[PROPERTY_VALUE_MAX]; + char fuse_sdcard[PROPERTY_VALUE_MAX]; + char *sd_mnt_point; + int num_vols; + struct volume_info *vol_list = 0; + off64_t previously_encrypted_upto = 0; +printf("cryptfs_enable_internal disabled by TWRP\n"); +return -1; + if (!strcmp(howarg, "wipe")) { + how = CRYPTO_ENABLE_WIPE; + } else if (! strcmp(howarg, "inplace")) { + how = CRYPTO_ENABLE_INPLACE; + } else { + /* Shouldn't happen, as CommandListener vets the args */ + goto error_unencrypted; + } + + /* See if an encryption was underway and interrupted */ + if (how == CRYPTO_ENABLE_INPLACE + && get_crypt_ftr_and_key(&crypt_ftr) == 0 + && (crypt_ftr.flags & CRYPT_ENCRYPTION_IN_PROGRESS)) { + previously_encrypted_upto = crypt_ftr.encrypted_upto; + crypt_ftr.encrypted_upto = 0; + crypt_ftr.flags &= ~CRYPT_ENCRYPTION_IN_PROGRESS; + + /* At this point, we are in an inconsistent state. Until we successfully + complete encryption, a reboot will leave us broken. So mark the + encryption failed in case that happens. + On successfully completing encryption, remove this flag */ + crypt_ftr.flags |= CRYPT_INCONSISTENT_STATE; + + put_crypt_ftr_and_key(&crypt_ftr); + } + + property_get("ro.crypto.state", encrypted_state, ""); + if (!strcmp(encrypted_state, "encrypted") && !previously_encrypted_upto) { + printf("Device is already running encrypted, aborting"); + goto error_unencrypted; + } + + // TODO refactor fs_mgr_get_crypt_info to get both in one call + fs_mgr_get_crypt_info(fstab, key_loc, 0, sizeof(key_loc)); + fs_mgr_get_crypt_info(fstab, 0, real_blkdev, sizeof(real_blkdev)); + + /* Get the size of the real block device */ + fd = open(real_blkdev, O_RDONLY); + if ( (nr_sec = get_blkdev_size(fd)) == 0) { + printf("Cannot get size of block device %s\n", real_blkdev); + goto error_unencrypted; + } + close(fd); + + /* If doing inplace encryption, make sure the orig fs doesn't include the crypto footer */ + if ((how == CRYPTO_ENABLE_INPLACE) && (!strcmp(key_loc, KEY_IN_FOOTER))) { + unsigned int fs_size_sec, max_fs_size_sec; + fs_size_sec = get_fs_size(real_blkdev); + if (fs_size_sec == 0) + fs_size_sec = get_f2fs_filesystem_size_sec(real_blkdev); + + max_fs_size_sec = nr_sec - (CRYPT_FOOTER_OFFSET / CRYPT_SECTOR_SIZE); + + if (fs_size_sec > max_fs_size_sec) { + printf("Orig filesystem overlaps crypto footer region. Cannot encrypt in place."); + goto error_unencrypted; + } + } + + /* Get a wakelock as this may take a while, and we don't want the + * device to sleep on us. We'll grab a partial wakelock, and if the UI + * wants to keep the screen on, it can grab a full wakelock. + */ + snprintf(lockid, sizeof(lockid), "enablecrypto%d", (int) getpid()); + acquire_wake_lock(PARTIAL_WAKE_LOCK, lockid); + + /* Get the sdcard mount point */ + sd_mnt_point = getenv("EMULATED_STORAGE_SOURCE"); + if (!sd_mnt_point) { + sd_mnt_point = getenv("EXTERNAL_STORAGE"); + } + if (!sd_mnt_point) { + sd_mnt_point = "/mnt/sdcard"; + } + + /* TODO + * Currently do not have test devices with multiple encryptable volumes. + * When we acquire some, re-add support. + */ + num_vols=0/*vold_getNumDirectVolumes()*/; + vol_list = malloc(sizeof(struct volume_info) * num_vols); + //vold_getDirectVolumeList(vol_list); + + for (i=0; i= 0) { + write(fd, "--wipe_data\n", strlen("--wipe_data\n") + 1); + write(fd, "--reason=cryptfs_enable_internal\n", strlen("--reason=cryptfs_enable_internal\n") + 1); + close(fd); + } else { + printf("could not open /cache/recovery/command\n"); + } + cryptfs_reboot(recovery); + } else { + /* set property to trigger dialog */ + property_set("vold.encrypt_progress", "error_partially_encrypted"); + release_wake_lock(lockid); + } + return -1; + } + + /* hrm, the encrypt step claims success, but the reboot failed. + * This should not happen. + * Set the property and return. Hope the framework can deal with it. + */ + property_set("vold.encrypt_progress", "error_reboot_failed"); + release_wake_lock(lockid); + return rc; + +error_unencrypted: + free(vol_list); + property_set("vold.encrypt_progress", "error_not_encrypted"); + if (lockid[0]) { + release_wake_lock(lockid); + } + return -1; + +error_shutting_down: + /* we failed, and have not encrypted anthing, so the users's data is still intact, + * but the framework is stopped and not restarted to show the error, so it's up to + * vold to restart the system. + */ + printf("Error enabling encryption after framework is shutdown, no data changed, restarting system"); + cryptfs_reboot(reboot); + + /* shouldn't get here */ + property_set("vold.encrypt_progress", "error_shutting_down"); + free(vol_list); + if (lockid[0]) { + release_wake_lock(lockid); + } + return -1; +} + +int cryptfs_enable(char *howarg, int type, char *passwd, int allow_reboot) +{ + char* adjusted_passwd = adjust_passwd(passwd); + if (adjusted_passwd) { + passwd = adjusted_passwd; + } + + int rc = cryptfs_enable_internal(howarg, type, passwd, allow_reboot); + + free(adjusted_passwd); + return rc; +} + +int cryptfs_enable_default(char *howarg, int allow_reboot) +{ + return cryptfs_enable_internal(howarg, CRYPT_TYPE_DEFAULT, + DEFAULT_PASSWORD, allow_reboot); +} + +int cryptfs_changepw(int crypt_type, const char *newpw) +{ + struct crypt_mnt_ftr crypt_ftr; + unsigned char decrypted_master_key[KEY_LEN_BYTES]; + + /* This is only allowed after we've successfully decrypted the master key */ + if (!master_key_saved) { + printf("Key not saved, aborting"); + return -1; + } + + if (crypt_type < 0 || crypt_type > CRYPT_TYPE_MAX_TYPE) { + printf("Invalid crypt_type %d", crypt_type); + return -1; + } + + /* get key */ + if (get_crypt_ftr_and_key(&crypt_ftr)) { + printf("Error getting crypt footer and key"); + return -1; + } + + crypt_ftr.crypt_type = crypt_type; + + char* adjusted_passwd = adjust_passwd(newpw); + if (adjusted_passwd) { + newpw = adjusted_passwd; + } + + encrypt_master_key(crypt_type == CRYPT_TYPE_DEFAULT ? DEFAULT_PASSWORD + : newpw, + crypt_ftr.salt, + saved_master_key, + crypt_ftr.master_key, + &crypt_ftr); + + /* save the key */ + put_crypt_ftr_and_key(&crypt_ftr); + + free(adjusted_passwd); + return 0; +} + +static int persist_get_key(char *fieldname, char *value) +{ + unsigned int i; + + if (persist_data == NULL) { + return -1; + } + for (i = 0; i < persist_data->persist_valid_entries; i++) { + if (!strncmp(persist_data->persist_entry[i].key, fieldname, PROPERTY_KEY_MAX)) { + /* We found it! */ + strlcpy(value, persist_data->persist_entry[i].val, PROPERTY_VALUE_MAX); + return 0; + } + } + + return -1; +} + +static int persist_set_key(char *fieldname, char *value, int encrypted) +{ + unsigned int i; + unsigned int num; + struct crypt_mnt_ftr crypt_ftr; + unsigned int max_persistent_entries; + unsigned int dsize; + + if (persist_data == NULL) { + return -1; + } + + /* If encrypted, use the values from the crypt_ftr, otherwise + * use the values for the current spec. + */ + if (encrypted) { + if(get_crypt_ftr_and_key(&crypt_ftr)) { + return -1; + } + dsize = crypt_ftr.persist_data_size; + } else { + dsize = CRYPT_PERSIST_DATA_SIZE; + } + max_persistent_entries = (dsize - sizeof(struct crypt_persist_data)) / + sizeof(struct crypt_persist_entry); + + num = persist_data->persist_valid_entries; + + for (i = 0; i < num; i++) { + if (!strncmp(persist_data->persist_entry[i].key, fieldname, PROPERTY_KEY_MAX)) { + /* We found an existing entry, update it! */ + memset(persist_data->persist_entry[i].val, 0, PROPERTY_VALUE_MAX); + strlcpy(persist_data->persist_entry[i].val, value, PROPERTY_VALUE_MAX); + return 0; + } + } + + /* We didn't find it, add it to the end, if there is room */ + if (persist_data->persist_valid_entries < max_persistent_entries) { + memset(&persist_data->persist_entry[num], 0, sizeof(struct crypt_persist_entry)); + strlcpy(persist_data->persist_entry[num].key, fieldname, PROPERTY_KEY_MAX); + strlcpy(persist_data->persist_entry[num].val, value, PROPERTY_VALUE_MAX); + persist_data->persist_valid_entries++; + return 0; + } + + return -1; +} + +/* Return the value of the specified field. */ +int cryptfs_getfield(char *fieldname, char *value, int len) +{ + char temp_value[PROPERTY_VALUE_MAX]; + char real_blkdev[MAXPATHLEN]; + /* 0 is success, 1 is not encrypted, + * -1 is value not set, -2 is any other error + */ + int rc = -2; + + if (persist_data == NULL) { + load_persistent_data(); + if (persist_data == NULL) { + printf("Getfield error, cannot load persistent data"); + goto out; + } + } + + if (!persist_get_key(fieldname, temp_value)) { + /* We found it, copy it to the caller's buffer and return */ + strlcpy(value, temp_value, len); + rc = 0; + } else { + /* Sadness, it's not there. Return the error */ + rc = -1; + } + +out: + return rc; +} + +/* Set the value of the specified field. */ +int cryptfs_setfield(char *fieldname, char *value) +{ + struct crypt_persist_data stored_pdata; + struct crypt_persist_data *pdata_p; + struct crypt_mnt_ftr crypt_ftr; + char encrypted_state[PROPERTY_VALUE_MAX]; + /* 0 is success, -1 is an error */ + int rc = -1; + int encrypted = 0; + + if (persist_data == NULL) { + load_persistent_data(); + if (persist_data == NULL) { + printf("Setfield error, cannot load persistent data"); + goto out; + } + } + + property_get("ro.crypto.state", encrypted_state, ""); + if (!strcmp(encrypted_state, "encrypted") ) { + encrypted = 1; + } + + if (persist_set_key(fieldname, value, encrypted)) { + goto out; + } + + /* If we are running encrypted, save the persistent data now */ + if (encrypted) { + if (save_persistent_data()) { + printf("Setfield error, cannot save persistent data"); + goto out; + } + } + + rc = 0; + +out: + return rc; +} + +/* Checks userdata. Attempt to mount the volume if default- + * encrypted. + * On success trigger next init phase and return 0. + * Currently do not handle failure - see TODO below. + */ +int cryptfs_mount_default_encrypted(void) +{ + char decrypt_state[PROPERTY_VALUE_MAX]; + property_get("vold.decrypt", decrypt_state, "0"); + if (!strcmp(decrypt_state, "0")) { + printf("Not encrypted - should not call here"); + } else { + int crypt_type = cryptfs_get_password_type(); + if (crypt_type < 0 || crypt_type > CRYPT_TYPE_MAX_TYPE) { + printf("Bad crypt type - error"); + } else if (crypt_type != CRYPT_TYPE_DEFAULT) { + printf("Password is not default - " + "starting min framework to prompt"); + property_set("vold.decrypt", "trigger_restart_min_framework"); + return 0; + } else if (cryptfs_check_passwd(DEFAULT_PASSWORD) == 0) { + printf("Password is default - restarting filesystem"); + cryptfs_restart_internal(0); + return 0; + } else { + printf("Encrypted, default crypt type but can't decrypt"); + } + } + + /** Corrupt. Allow us to boot into framework, which will detect bad + crypto when it calls do_crypto_complete, then do a factory reset + */ + property_set("vold.decrypt", "trigger_restart_min_framework"); + return 0; +} + +/* Returns type of the password, default, pattern, pin or password. + */ +int cryptfs_get_password_type(void) +{ + struct crypt_mnt_ftr crypt_ftr; + char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)]; + char propbuf[PROPERTY_VALUE_MAX]; + + property_get("ro.hardware", propbuf, ""); + snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf); + + fstab = fs_mgr_read_fstab(fstab_filename); + if (!fstab) { + printf("failed to open %s\n", fstab_filename); + return -1; + } + + if (get_crypt_ftr_and_key(&crypt_ftr)) { + printf("Error getting crypt footer and key\n"); + return -1; + } + + if (crypt_ftr.flags & CRYPT_INCONSISTENT_STATE) { + return -1; + } + + return crypt_ftr.crypt_type; +} + +char* cryptfs_get_password() +{ + struct timespec now; + clock_gettime(CLOCK_MONOTONIC, &now); + if (now.tv_sec < password_expiry_time) { + return password; + } else { + cryptfs_clear_password(); + return 0; + } +} + +void cryptfs_clear_password() +{ + if (password) { + size_t len = strlen(password); + memset(password, 0, len); + free(password); + password = 0; + password_expiry_time = 0; + } +} diff --git a/crypto/lollipop/cryptfs.h b/crypto/lollipop/cryptfs.h new file mode 100644 index 000000000..b95a290cf --- /dev/null +++ b/crypto/lollipop/cryptfs.h @@ -0,0 +1,231 @@ +/* + * 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, or in a separate partition. It's location + * is specified by a property set in init..rc. + * The structure allocates 48 bytes for a key, but the real key size is + * specified in the struct. Currently, the code is hardcoded to use 128 + * bit keys. + * The fields after salt are only valid in rev 1.1 and later stuctures. + * Obviously, the filesystem does not include the last 16 kbytes + * of the partition if the crypt_mnt_ftr lives at the end of the + * partition. + */ + +#include +#include "openssl/sha.h" + +/* The current cryptfs version */ +#define CURRENT_MAJOR_VERSION 1 +#define CURRENT_MINOR_VERSION 3 + +#define CRYPT_FOOTER_OFFSET 0x4000 +#define CRYPT_FOOTER_TO_PERSIST_OFFSET 0x1000 +#define CRYPT_PERSIST_DATA_SIZE 0x1000 + +#define MAX_CRYPTO_TYPE_NAME_LEN 64 + +#define MAX_KEY_LEN 48 +#define SALT_LEN 16 +#define SCRYPT_LEN 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 /* Encryption partially completed, + encrypted_upto valid*/ +#define CRYPT_INCONSISTENT_STATE 0x4 /* Set when starting encryption, clear when + exit cleanly, either through success or + correctly marked partial encryption */ +#define CRYPT_DATA_CORRUPT 0x8 /* Set when encryption is fine, but the + underlying volume is corrupt */ + +/* Allowed values for type in the structure below */ +#define CRYPT_TYPE_PASSWORD 0 /* master_key is encrypted with a password + * Must be zero to be compatible with pre-L + * devices where type is always password.*/ +#define CRYPT_TYPE_DEFAULT 1 /* master_key is encrypted with default + * password */ +#define CRYPT_TYPE_PATTERN 2 /* master_key is encrypted with a pattern */ +#define CRYPT_TYPE_PIN 3 /* master_key is encrypted with a pin */ +#define CRYPT_TYPE_MAX_TYPE 3 /* type cannot be larger than this value */ + +#define CRYPT_MNT_MAGIC 0xD0B5B1C4 +#define PERSIST_DATA_MAGIC 0xE950CD44 + +#define SCRYPT_PROP "ro.crypto.scrypt_params" +#define SCRYPT_DEFAULTS { 15, 3, 1 } + +/* Key Derivation Function algorithms */ +#define KDF_PBKDF2 1 +#define KDF_SCRYPT 2 +/* TODO(paullawrence): Remove KDF_SCRYPT_KEYMASTER_UNPADDED and KDF_SCRYPT_KEYMASTER_BADLY_PADDED + * when it is safe to do so. */ +#define KDF_SCRYPT_KEYMASTER_UNPADDED 3 +#define KDF_SCRYPT_KEYMASTER_BADLY_PADDED 4 +#define KDF_SCRYPT_KEYMASTER 5 + +/* Maximum allowed keymaster blob size. */ +#define KEYMASTER_BLOB_SIZE 2048 + +/* __le32 and __le16 defined in system/extras/ext4_utils/ext4_utils.h */ +#define __le8 unsigned char + +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 crypt_type; /* how master_key is encrypted. Must be a + * CRYPT_TYPE_XXX value */ + __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 */ + unsigned char crypto_type_name[MAX_CRYPTO_TYPE_NAME_LEN]; /* The type of encryption + needed to decrypt this + partition, null terminated */ + __le32 spare2; /* ignored */ + unsigned char master_key[MAX_KEY_LEN]; /* The encrypted key for decrypting the filesystem */ + unsigned char salt[SALT_LEN]; /* The salt used for this encryption */ + __le64 persist_data_offset[2]; /* Absolute offset to both copies of crypt_persist_data + * on device with that info, either the footer of the + * real_blkdevice or the metadata partition. */ + + __le32 persist_data_size; /* The number of bytes allocated to each copy of the + * persistent data table*/ + + __le8 kdf_type; /* The key derivation function used. */ + + /* scrypt parameters. See www.tarsnap.com/scrypt/scrypt.pdf */ + __le8 N_factor; /* (1 << N) */ + __le8 r_factor; /* (1 << r) */ + __le8 p_factor; /* (1 << p) */ + __le64 encrypted_upto; /* If we are in state CRYPT_ENCRYPTION_IN_PROGRESS and + we have to stop (e.g. power low) this is the last + encrypted 512 byte sector.*/ + __le8 hash_first_block[SHA256_DIGEST_LENGTH]; /* When CRYPT_ENCRYPTION_IN_PROGRESS + set, hash of first block, used + to validate before continuing*/ + + /* key_master key, used to sign the derived key which is then used to generate + * the intermediate key + * This key should be used for no other purposes! We use this key to sign unpadded + * data, which is acceptable but only if the key is not reused elsewhere. */ + __le8 keymaster_blob[KEYMASTER_BLOB_SIZE]; + __le32 keymaster_blob_size; + + /* Store scrypt of salted intermediate key. When decryption fails, we can + check if this matches, and if it does, we know that the problem is with the + drive, and there is no point in asking the user for more passwords. + + Note that if any part of this structure is corrupt, this will not match and + we will continue to believe the user entered the wrong password. In that + case the only solution is for the user to enter a password enough times to + force a wipe. + + Note also that there is no need to worry about migration. If this data is + wrong, we simply won't recognise a right password, and will continue to + prompt. On the first password change, this value will be populated and + then we will be OK. + */ + unsigned char scrypted_intermediate_key[SCRYPT_LEN]; +}; + +/* Persistant data that should be available before decryption. + * Things like airplane mode, locale and timezone are kept + * here and can be retrieved by the CryptKeeper UI to properly + * configure the phone before asking for the password + * This is only valid if the major and minor version above + * is set to 1.1 or higher. + * + * This is a 4K structure. There are 2 copies, and the code alternates + * writing one and then clearing the previous one. The reading + * code reads the first valid copy it finds, based on the magic number. + * The absolute offset to the first of the two copies is kept in rev 1.1 + * and higher crypt_mnt_ftr structures. + */ +struct crypt_persist_entry { + char key[PROPERTY_KEY_MAX]; + char val[PROPERTY_VALUE_MAX]; +}; + +/* Should be exactly 4K in size */ +struct crypt_persist_data { + __le32 persist_magic; + __le32 persist_valid_entries; + __le32 persist_spare[30]; + struct crypt_persist_entry persist_entry[0]; +}; + +struct volume_info { + unsigned int size; + unsigned int flags; + struct crypt_mnt_ftr crypt_ftr; + char mnt_point[256]; + char blk_dev[256]; + char crypto_blkdev[256]; + char label[256]; +}; +#define VOL_NONREMOVABLE 0x1 +#define VOL_ENCRYPTABLE 0x2 +#define VOL_PRIMARY 0x4 +#define VOL_PROVIDES_ASEC 0x8 + +#define DATA_MNT_POINT "/data" + +/* Return values for cryptfs_crypto_complete */ +#define CRYPTO_COMPLETE_NOT_ENCRYPTED 1 +#define CRYPTO_COMPLETE_ENCRYPTED 0 +#define CRYPTO_COMPLETE_BAD_METADATA -1 +#define CRYPTO_COMPLETE_PARTIAL -2 +#define CRYPTO_COMPLETE_INCONSISTENT -3 +#define CRYPTO_COMPLETE_CORRUPT -4 + +/* Return values for cryptfs_enable_inplace*() */ +#define ENABLE_INPLACE_OK 0 +#define ENABLE_INPLACE_ERR_OTHER -1 +#define ENABLE_INPLACE_ERR_DEV -2 /* crypto_blkdev issue */ + +#ifdef __cplusplus +extern "C" { +#endif + + typedef int (*kdf_func)(const char *passwd, const unsigned char *salt, + unsigned char *ikey, void *params); + + int cryptfs_crypto_complete(void); + int cryptfs_check_footer(void); + int cryptfs_check_passwd(char *pw); + int cryptfs_verify_passwd(char *newpw); + int cryptfs_restart(void); + int cryptfs_enable(char *flag, int type, char *passwd, int allow_reboot); + int cryptfs_changepw(int type, const char *newpw); + int cryptfs_enable_default(char *flag, int allow_reboot); + int cryptfs_setup_volume(const char *label, int major, int minor, + char *crypto_dev_path, unsigned int max_pathlen, + int *new_major, int *new_minor); + int cryptfs_revert_volume(const char *label); + int cryptfs_getfield(char *fieldname, char *value, int len); + int cryptfs_setfield(char *fieldname, char *value); + int cryptfs_mount_default_encrypted(void); + int cryptfs_get_password_type(void); + char* cryptfs_get_password(void); + void cryptfs_clear_password(void); +#ifdef __cplusplus +} +#endif -- cgit v1.2.3