/* * 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; }