From 31f6ee88ce0d5155cb62d1b928604568318981a3 Mon Sep 17 00:00:00 2001 From: Oscar Montemayor Date: Thu, 25 Feb 2010 16:47:02 -0800 Subject: Encrypted File Systems part 3. Recovery changes. Change-Id: I932f73a6f937aac061128e1134eab08c30f0471d --- Android.mk | 2 +- efs_migration.c | 183 ----------------------------- efs_migration.h | 40 ------- encryptedfs_provisioning.c | 284 +++++++++++++++++++++++++++++++++++++++++++++ encryptedfs_provisioning.h | 51 ++++++++ recovery.c | 36 +++--- 6 files changed, 354 insertions(+), 242 deletions(-) delete mode 100644 efs_migration.c delete mode 100644 efs_migration.h create mode 100644 encryptedfs_provisioning.c create mode 100644 encryptedfs_provisioning.h diff --git a/Android.mk b/Android.mk index c556db36b..b0fefbd90 100644 --- a/Android.mk +++ b/Android.mk @@ -13,7 +13,7 @@ LOCAL_SRC_FILES := \ roots.c \ ui.c \ verifier.c \ - efs_migration.c + encryptedfs_provisioning.c LOCAL_SRC_FILES += test_roots.c diff --git a/efs_migration.c b/efs_migration.c deleted file mode 100644 index aeadd1865..000000000 --- a/efs_migration.c +++ /dev/null @@ -1,183 +0,0 @@ -/* - * Copyright (C) 2009 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#include -#include -#include -#include -#include -#include -#include - -#include "efs_migration.h" -#include "cutils/misc.h" -#include "cutils/properties.h" -#include "common.h" -#include "mtdutils/mtdutils.h" -#include "mtdutils/mounts.h" -#include "roots.h" - -const char* efs_enabled_property = "persist.security.efs.enabled"; -const char* efs_transition_property = "persist.security.efs.trans"; -const char* efs_property_dir = "/data/property/"; - -void get_property_file_name(char *buffer, const char *property_name) { - sprintf(buffer, "%s%s", efs_property_dir, property_name); -} - -int get_text_file_contents(char *buffer, int buf_size, char *file_name) { - FILE *in_file; - char *read_data; - - in_file = fopen(file_name, "r"); - if (in_file == NULL) { - LOGE("Encrypted FS: error accessing properties."); - return EFS_ERROR; - } - - read_data = fgets(buffer, buf_size, in_file); - if (read_data == NULL) { - // Error or unexpected data - fclose(in_file); - LOGE("Encrypted FS: error accessing properties."); - return EFS_ERROR; - } - - fclose(in_file); - return EFS_OK; -} - -int set_text_file_contents(char *buffer, char *file_name) { - FILE *out_file; - int result; - - out_file = fopen(file_name, "w"); - if (out_file == NULL) { - LOGE("Encrypted FS: error setting up properties."); - return EFS_ERROR; - } - - result = fputs(buffer, out_file); - if (result != 0) { - // Error or unexpected data - fclose(out_file); - LOGE("Encrypted FS: error setting up properties."); - return EFS_ERROR; - } - - fflush(out_file); - fclose(out_file); - return EFS_OK; -} - - -int read_efs_boolean_property(const char *prop_name, int *value) { - char prop_file_name[PROPERTY_KEY_MAX + 32]; - char prop_value[PROPERTY_VALUE_MAX]; - int result; - - get_property_file_name(prop_file_name, prop_name); - result = get_text_file_contents(prop_value, PROPERTY_VALUE_MAX, prop_file_name); - - if (result < 0) { - return result; - } - - if (strncmp(prop_value, "1", 1) == 0) { - *value = 1; - } else if (strncmp(prop_value, "0", 1) == 0) { - *value = 0; - } else { - LOGE("Encrypted FS: error accessing properties."); - return EFS_ERROR; - } - - return EFS_OK; -} - -int write_efs_boolean_property(const char *prop_name, int value) { - char prop_file_name[PROPERTY_KEY_MAX + 32]; - char prop_value[PROPERTY_VALUE_MAX]; - int result; - - get_property_file_name(prop_file_name, prop_name); - - // Create the directory if needed - mkdir(efs_property_dir, 0755); - if (value == 1) { - result = set_text_file_contents("1", prop_file_name); - } else if (value == 0) { - result = set_text_file_contents("0", prop_file_name); - } else { - return EFS_ERROR; - } - if (result < 0) { - return result; - } - - return EFS_OK; -} - -int read_encrypted_fs_info(encrypted_fs_info *efs_data) { - int result; - int value; - result = ensure_root_path_mounted("DATA:"); - if (result != 0) { - LOGE("Encrypted FS: error mounting userdata partition."); - return EFS_ERROR; - } - - // STOPSHIP: Read the EFS key from a file (TBD later) - // Future code goes here... - - result = ensure_root_path_unmounted("DATA:"); - if (result != 0) { - LOGE("Encrypted FS: error unmounting data partition."); - return EFS_ERROR; - } - - return EFS_OK; -} - -int restore_encrypted_fs_info(encrypted_fs_info *efs_data) { - int result; - result = ensure_root_path_mounted("DATA:"); - if (result != 0) { - LOGE("Encrypted FS: error mounting userdata partition."); - return EFS_ERROR; - } - - // Set the EFS properties to their respective values - result = write_efs_boolean_property(efs_enabled_property, efs_data->encrypted_fs_mode); - if (result != 0) { - return result; - } - - // Signal "transition" of Encrypted File System settings - result = write_efs_boolean_property(efs_transition_property, 1); - if (result != 0) { - return result; - } - - result = ensure_root_path_unmounted("DATA:"); - if (result != 0) { - LOGE("Encrypted FS: error unmounting data partition."); - return EFS_ERROR; - } - - return EFS_OK; -} - diff --git a/efs_migration.h b/efs_migration.h deleted file mode 100644 index 7857f94fe..000000000 --- a/efs_migration.h +++ /dev/null @@ -1,40 +0,0 @@ -/* - * Copyright (C) 2009 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#include - -#ifndef __EFS_MIGRATION_H__ -#define __EFS_MIGRATION_H__ - -#define MODE_ENCRYPTEDFS_DISABLED 0 -#define MODE_ENCRYPTEDFS_ENABLED 1 - -#define EFS_OK 0 -#define EFS_ERROR (-1) - -struct encrypted_fs_info { - int encrypted_fs_mode; - char *encrypted_fs_key; -}; - -typedef struct encrypted_fs_info encrypted_fs_info; - -int read_encrypted_fs_info(encrypted_fs_info *efs_data); - -int restore_encrypted_fs_info(encrypted_fs_info *efs_data); - -#endif /* __EFS_MIGRATION_H__ */ - diff --git a/encryptedfs_provisioning.c b/encryptedfs_provisioning.c new file mode 100644 index 000000000..2bcfec161 --- /dev/null +++ b/encryptedfs_provisioning.c @@ -0,0 +1,284 @@ +/* + * Copyright (C) 2009 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "encryptedfs_provisioning.h" +#include "cutils/misc.h" +#include "cutils/properties.h" +#include "common.h" +#include "mtdutils/mtdutils.h" +#include "mtdutils/mounts.h" +#include "roots.h" + +const char* encrypted_fs_enabled_property = "persist.security.secfs.enabled"; +const char* encrypted_fs_property_dir = "/data/property/"; +const char* encrypted_fs_system_dir = "/data/system/"; +const char* encrypted_fs_key_file_name = "/data/fs_key.dat"; +const char* encrypted_fs_salt_file_name = "/data/hash_salt.dat"; +const char* encrypted_fs_hash_file_src_name = "/data/system/password.key"; +const char* encrypted_fs_hash_file_dst_name = "/data/hash.dat"; +const char* encrypted_fs_entropy_file_src_name = "/data/system/entropy.dat"; +const char* encrypted_fs_entropy_file_dst_name = "/data/ported_entropy.dat"; + +void get_property_file_name(char *buffer, const char *property_name) { + sprintf(buffer, "%s%s", encrypted_fs_property_dir, property_name); +} + +int get_binary_file_contents(char *buffer, int buf_size, const char *file_name, int *out_size) { + FILE *in_file; + int read_bytes; + + in_file = fopen(file_name, "r"); + if (in_file == NULL) { + LOGE("Secure FS: error accessing key file."); + return ENCRYPTED_FS_ERROR; + } + + read_bytes = fread(buffer, 1, buf_size, in_file); + if (out_size == NULL) { + if (read_bytes != buf_size) { + // Error or unexpected data + fclose(in_file); + LOGE("Secure FS: error reading conmplete key."); + return ENCRYPTED_FS_ERROR; + } + } else { + *out_size = read_bytes; + } + fclose(in_file); + return ENCRYPTED_FS_OK; +} + +int set_binary_file_contents(char *buffer, int buf_size, const char *file_name) { + FILE *out_file; + int write_bytes; + + out_file = fopen(file_name, "w"); + if (out_file == NULL) { + LOGE("Secure FS: error setting up key file."); + return ENCRYPTED_FS_ERROR; + } + + write_bytes = fwrite(buffer, 1, buf_size, out_file); + if (write_bytes != buf_size) { + // Error or unexpected data + fclose(out_file); + LOGE("Secure FS: error reading conmplete key."); + return ENCRYPTED_FS_ERROR; + } + + fclose(out_file); + return ENCRYPTED_FS_OK; +} + +int get_text_file_contents(char *buffer, int buf_size, char *file_name) { + FILE *in_file; + char *read_data; + + in_file = fopen(file_name, "r"); + if (in_file == NULL) { + LOGE("Secure FS: error accessing properties."); + return ENCRYPTED_FS_ERROR; + } + + read_data = fgets(buffer, buf_size, in_file); + if (read_data == NULL) { + // Error or unexpected data + fclose(in_file); + LOGE("Secure FS: error accessing properties."); + return ENCRYPTED_FS_ERROR; + } + + fclose(in_file); + return ENCRYPTED_FS_OK; +} + +int set_text_file_contents(char *buffer, char *file_name) { + FILE *out_file; + int result; + + out_file = fopen(file_name, "w"); + if (out_file == NULL) { + LOGE("Secure FS: error setting up properties."); + return ENCRYPTED_FS_ERROR; + } + + result = fputs(buffer, out_file); + if (result != 0) { + // Error or unexpected data + fclose(out_file); + LOGE("Secure FS: error setting up properties."); + return ENCRYPTED_FS_ERROR; + } + + fflush(out_file); + fclose(out_file); + return ENCRYPTED_FS_OK; +} + +int read_encrypted_fs_boolean_property(const char *prop_name, int *value) { + char prop_file_name[PROPERTY_KEY_MAX + 32]; + char prop_value[PROPERTY_VALUE_MAX]; + int result; + + get_property_file_name(prop_file_name, prop_name); + result = get_text_file_contents(prop_value, PROPERTY_VALUE_MAX, prop_file_name); + + if (result < 0) { + return result; + } + + if (strncmp(prop_value, "1", 1) == 0) { + *value = 1; + } else if (strncmp(prop_value, "0", 1) == 0) { + *value = 0; + } else { + LOGE("Secure FS: error accessing properties."); + return ENCRYPTED_FS_ERROR; + } + + return ENCRYPTED_FS_OK; +} + +int write_encrypted_fs_boolean_property(const char *prop_name, int value) { + char prop_file_name[PROPERTY_KEY_MAX + 32]; + char prop_value[PROPERTY_VALUE_MAX]; + int result; + + get_property_file_name(prop_file_name, prop_name); + + // Create the directory if needed + mkdir(encrypted_fs_property_dir, 0755); + if (value == 1) { + result = set_text_file_contents("1", prop_file_name); + } else if (value == 0) { + result = set_text_file_contents("0", prop_file_name); + } else { + return ENCRYPTED_FS_ERROR; + } + if (result < 0) { + return result; + } + + return ENCRYPTED_FS_OK; +} + +int read_encrypted_fs_info(encrypted_fs_info *encrypted_fs_data) { + int result; + int value; + result = ensure_root_path_mounted("DATA:"); + if (result != 0) { + LOGE("Secure FS: error mounting userdata partition."); + return ENCRYPTED_FS_ERROR; + } + + // Read the pre-generated encrypted FS key, password hash and salt. + result = get_binary_file_contents(encrypted_fs_data->key, ENCRYPTED_FS_KEY_SIZE, + encrypted_fs_key_file_name, NULL); + if (result != 0) { + LOGE("Secure FS: error reading generated file system key."); + return ENCRYPTED_FS_ERROR; + } + + result = get_binary_file_contents(encrypted_fs_data->salt, ENCRYPTED_FS_SALT_SIZE, + encrypted_fs_salt_file_name, &(encrypted_fs_data->salt_length)); + if (result != 0) { + LOGE("Secure FS: error reading file system salt."); + return ENCRYPTED_FS_ERROR; + } + + result = get_binary_file_contents(encrypted_fs_data->hash, ENCRYPTED_FS_MAX_HASH_SIZE, + encrypted_fs_hash_file_src_name, &(encrypted_fs_data->hash_length)); + if (result != 0) { + LOGE("Secure FS: error reading password hash."); + return ENCRYPTED_FS_ERROR; + } + + result = get_binary_file_contents(encrypted_fs_data->entropy, ENTROPY_MAX_SIZE, + encrypted_fs_entropy_file_src_name, &(encrypted_fs_data->entropy_length)); + if (result != 0) { + LOGE("Secure FS: error reading ported entropy."); + return ENCRYPTED_FS_ERROR; + } + + result = ensure_root_path_unmounted("DATA:"); + if (result != 0) { + LOGE("Secure FS: error unmounting data partition."); + return ENCRYPTED_FS_ERROR; + } + + return ENCRYPTED_FS_OK; +} + +int restore_encrypted_fs_info(encrypted_fs_info *encrypted_fs_data) { + int result; + result = ensure_root_path_mounted("DATA:"); + if (result != 0) { + LOGE("Secure FS: error mounting userdata partition."); + return ENCRYPTED_FS_ERROR; + } + + // Write the pre-generated secure FS key, password hash and salt. + result = set_binary_file_contents(encrypted_fs_data->key, ENCRYPTED_FS_KEY_SIZE, + encrypted_fs_key_file_name); + if (result != 0) { + LOGE("Secure FS: error writing generated file system key."); + return ENCRYPTED_FS_ERROR; + } + + result = set_binary_file_contents(encrypted_fs_data->salt, encrypted_fs_data->salt_length, + encrypted_fs_salt_file_name); + if (result != 0) { + LOGE("Secure FS: error writing file system salt."); + return ENCRYPTED_FS_ERROR; + } + + result = set_binary_file_contents(encrypted_fs_data->hash, encrypted_fs_data->hash_length, + encrypted_fs_hash_file_dst_name); + if (result != 0) { + LOGE("Secure FS: error writing password hash."); + return ENCRYPTED_FS_ERROR; + } + + result = set_binary_file_contents(encrypted_fs_data->entropy, encrypted_fs_data->entropy_length, + encrypted_fs_entropy_file_dst_name); + if (result != 0) { + LOGE("Secure FS: error writing ported entropy."); + return ENCRYPTED_FS_ERROR; + } + + // Set the secure FS properties to their respective values + result = write_encrypted_fs_boolean_property(encrypted_fs_enabled_property, encrypted_fs_data->mode); + if (result != 0) { + return result; + } + + result = ensure_root_path_unmounted("DATA:"); + if (result != 0) { + LOGE("Secure FS: error unmounting data partition."); + return ENCRYPTED_FS_ERROR; + } + + return ENCRYPTED_FS_OK; +} + diff --git a/encryptedfs_provisioning.h b/encryptedfs_provisioning.h new file mode 100644 index 000000000..284605d20 --- /dev/null +++ b/encryptedfs_provisioning.h @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2009 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include + +#ifndef __ENCRYPTEDFS_PROVISIONING_H__ +#define __ENCRYPTEDFS_PROVISIONING_H__ + +#define MODE_ENCRYPTED_FS_DISABLED 0 +#define MODE_ENCRYPTED_FS_ENABLED 1 + +#define ENCRYPTED_FS_OK 0 +#define ENCRYPTED_FS_ERROR (-1) + +#define ENCRYPTED_FS_KEY_SIZE 16 +#define ENCRYPTED_FS_SALT_SIZE 16 +#define ENCRYPTED_FS_MAX_HASH_SIZE 128 +#define ENTROPY_MAX_SIZE 4096 + +struct encrypted_fs_info { + int mode; + char key[ENCRYPTED_FS_KEY_SIZE]; + char salt[ENCRYPTED_FS_SALT_SIZE]; + int salt_length; + char hash[ENCRYPTED_FS_MAX_HASH_SIZE]; + int hash_length; + char entropy[ENTROPY_MAX_SIZE]; + int entropy_length; +}; + +typedef struct encrypted_fs_info encrypted_fs_info; + +int read_encrypted_fs_info(encrypted_fs_info *secure_fs_data); + +int restore_encrypted_fs_info(encrypted_fs_info *secure_data); + +#endif /* __ENCRYPTEDFS_PROVISIONING_H__ */ + diff --git a/recovery.c b/recovery.c index 4c437e599..2454a07d8 100644 --- a/recovery.c +++ b/recovery.c @@ -36,15 +36,14 @@ #include "minzip/DirUtil.h" #include "roots.h" #include "recovery_ui.h" -#include "efs_migration.h" +#include "encryptedfs_provisioning.h" static const struct option OPTIONS[] = { { "send_intent", required_argument, NULL, 's' }, { "update_package", required_argument, NULL, 'u' }, { "wipe_data", no_argument, NULL, 'w' }, { "wipe_cache", no_argument, NULL, 'c' }, - // TODO{oam}: implement improved command line passing key, egnor to review. - { "set_encrypted_filesystem", required_argument, NULL, 'e' }, + { "set_encrypted_filesystems", required_argument, NULL, 'e' }, { NULL, 0, NULL, 0 }, }; @@ -111,9 +110,9 @@ static const char *TEMPORARY_LOG_FILE = "/tmp/recovery.log"; * -- after this, rebooting will (try to) restart the main system -- * 9. main() calls reboot() to boot main system * - * ENCRYPTED FILE SYSTEMS ENABLE/DISABLE + * SECURE FILE SYSTEMS ENABLE/DISABLE * 1. user selects "enable encrypted file systems" - * 2. main system writes "--set_encrypted_filesystem=on|off" to + * 2. main system writes "--set_encrypted_filesystems=on|off" to * /cache/recovery/command * 3. main system reboots into recovery * 4. get_args() writes BCB with "boot-recovery" and @@ -471,10 +470,10 @@ main(int argc, char **argv) { int previous_runs = 0; const char *send_intent = NULL; const char *update_package = NULL; - const char *efs_mode = NULL; + const char *encrypted_fs_mode = NULL; int wipe_data = 0, wipe_cache = 0; - int toggle_efs = 0; - encrypted_fs_info efs_data; + int toggle_secure_fs = 0; + encrypted_fs_info encrypted_fs_data; int arg; while ((arg = getopt_long(argc, argv, "", OPTIONS, NULL)) != -1) { @@ -484,7 +483,7 @@ main(int argc, char **argv) { case 'u': update_package = optarg; break; case 'w': wipe_data = wipe_cache = 1; break; case 'c': wipe_cache = 1; break; - case 'e': efs_mode = optarg; toggle_efs = 1; break; + case 'e': encrypted_fs_mode = optarg; toggle_secure_fs = 1; break; case '?': LOGE("Invalid command argument\n"); continue; @@ -504,12 +503,12 @@ main(int argc, char **argv) { int status = INSTALL_SUCCESS; - if (toggle_efs) { - if (strcmp(efs_mode,"on") == 0) { - efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_ENABLED; + if (toggle_secure_fs) { + if (strcmp(encrypted_fs_mode,"on") == 0) { + encrypted_fs_data.mode = MODE_ENCRYPTED_FS_ENABLED; ui_print("Enabling Encrypted FS.\n"); - } else if (strcmp(efs_mode,"off") == 0) { - efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_DISABLED; + } else if (strcmp(encrypted_fs_mode,"off") == 0) { + encrypted_fs_data.mode = MODE_ENCRYPTED_FS_DISABLED; ui_print("Disabling Encrypted FS.\n"); } else { ui_print("Error: invalid Encrypted FS setting.\n"); @@ -518,10 +517,10 @@ main(int argc, char **argv) { // Recovery strategy: if the data partition is damaged, disable encrypted file systems. // This preventsthe device recycling endlessly in recovery mode. - // TODO{oam}: implement improved recovery strategy later. egnor to review. - if (read_encrypted_fs_info(&efs_data)) { + if ((encrypted_fs_data.mode == MODE_ENCRYPTED_FS_ENABLED) && + (read_encrypted_fs_info(&encrypted_fs_data))) { ui_print("Encrypted FS change aborted, resetting to disabled state.\n"); - efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_DISABLED; + encrypted_fs_data.mode = MODE_ENCRYPTED_FS_DISABLED; } if (status != INSTALL_ERROR) { @@ -531,7 +530,8 @@ main(int argc, char **argv) { } else if (erase_root("CACHE:")) { ui_print("Cache wipe failed.\n"); status = INSTALL_ERROR; - } else if (restore_encrypted_fs_info(&efs_data)) { + } else if ((encrypted_fs_data.mode == MODE_ENCRYPTED_FS_ENABLED) && + (restore_encrypted_fs_info(&encrypted_fs_data))) { ui_print("Encrypted FS change aborted.\n"); status = INSTALL_ERROR; } else { -- cgit v1.2.3