cryptfs.h revision e87440703663f5ee326326f6438f3b00ea315623
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17/* This structure starts 16,384 bytes before the end of a hardware 18 * partition that is encrypted. 19 * Immediately following this structure is the encrypted key. 20 * The keysize field tells how long the key is, in bytes. 21 * Then there is 32 bytes of padding, 22 * Finally there is the salt used with the user password. 23 * The salt is fixed at 16 bytes long. 24 * Obviously, the filesystem does not include the last 16 kbytes 25 * of the partition. 26 */ 27 28#define CRYPT_FOOTER_OFFSET 0x4000 29 30#define MAX_CRYPTO_TYPE_NAME_LEN 64 31 32#define SALT_LEN 16 33#define KEY_TO_SALT_PADDING 32 34 35/* definitions of flags in the structure below */ 36#define CRYPT_MNT_KEY_UNENCRYPTED 0x1 /* The key for the partition is not encrypted. */ 37 38#define CRYPT_MNT_MAGIC 0xD0B5B1C4 39 40#define __le32 unsigned int 41#define __le16 unsigned short int 42 43struct crypt_mnt_ftr { 44 __le32 magic; /* See above */ 45 __le16 major_version; 46 __le16 minor_version; 47 __le32 ftr_size; /* in bytes, not including key following */ 48 __le32 flags; /* See above */ 49 __le32 keysize; /* in bytes */ 50 __le32 spare1; /* ignored */ 51 __le64 fs_size; /* Size of the encrypted fs, in 512 byte sectors */ 52 __le32 failed_decrypt_count; /* count of # of failed attempts to decrypt and 53 mount, set to 0 on successful mount */ 54 unsigned char crypto_type_name[MAX_CRYPTO_TYPE_NAME_LEN]; /* The type of encryption 55 needed to decrypt this 56 partition, null terminated */ 57}; 58 59#ifdef __cplusplus 60extern "C" { 61#endif 62 int cryptfs_check_passwd(char *pw); 63 int cryptfs_restart(void); 64 int cryptfs_enable(char *flag, char *passwd); 65 int cryptfs_changepw(char *oldpw, char *newpw); 66#ifdef __cplusplus 67} 68#endif 69 70