| Hyojun Kim | 63da420 | 2017-10-06 17:10:08 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fscrypt_private.h |
| 3 | * |
| 4 | * Copyright (C) 2015, Google, Inc. |
| 5 | * |
| 6 | * This contains encryption key functions. |
| 7 | * |
| 8 | * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015. |
| 9 | */ |
| 10 | |
| 11 | #ifndef _FSCRYPT_PRIVATE_H |
| 12 | #define _FSCRYPT_PRIVATE_H |
| 13 | |
| Jaegeuk Kim | 8dec074 | 2017-06-22 12:14:40 -0700 | [diff] [blame^] | 14 | #define __FS_HAS_ENCRYPTION 1 |
| 15 | #include <linux/fscrypt.h> |
| Hyojun Kim | 63da420 | 2017-10-06 17:10:08 -0700 | [diff] [blame] | 16 | #include <crypto/hash.h> |
| 17 | |
| 18 | /* Encryption parameters */ |
| 19 | #define FS_IV_SIZE 16 |
| 20 | #define FS_AES_128_ECB_KEY_SIZE 16 |
| 21 | #define FS_AES_128_CBC_KEY_SIZE 16 |
| 22 | #define FS_AES_128_CTS_KEY_SIZE 16 |
| 23 | #define FS_AES_256_GCM_KEY_SIZE 32 |
| 24 | #define FS_AES_256_CBC_KEY_SIZE 32 |
| 25 | #define FS_AES_256_CTS_KEY_SIZE 32 |
| 26 | #define FS_AES_256_XTS_KEY_SIZE 64 |
| 27 | |
| 28 | #define FS_KEY_DERIVATION_NONCE_SIZE 16 |
| 29 | |
| 30 | /** |
| 31 | * Encryption context for inode |
| 32 | * |
| 33 | * Protector format: |
| 34 | * 1 byte: Protector format (1 = this version) |
| 35 | * 1 byte: File contents encryption mode |
| 36 | * 1 byte: File names encryption mode |
| 37 | * 1 byte: Flags |
| 38 | * 8 bytes: Master Key descriptor |
| 39 | * 16 bytes: Encryption Key derivation nonce |
| 40 | */ |
| 41 | struct fscrypt_context { |
| 42 | u8 format; |
| 43 | u8 contents_encryption_mode; |
| 44 | u8 filenames_encryption_mode; |
| 45 | u8 flags; |
| 46 | u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE]; |
| 47 | u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE]; |
| 48 | } __packed; |
| 49 | |
| 50 | #define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1 |
| 51 | |
| 52 | /* |
| 53 | * A pointer to this structure is stored in the file system's in-core |
| 54 | * representation of an inode. |
| 55 | */ |
| 56 | struct fscrypt_info { |
| 57 | u8 ci_data_mode; |
| 58 | u8 ci_filename_mode; |
| 59 | u8 ci_flags; |
| 60 | struct crypto_skcipher *ci_ctfm; |
| 61 | struct crypto_cipher *ci_essiv_tfm; |
| 62 | u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE]; |
| 63 | }; |
| 64 | |
| 65 | typedef enum { |
| 66 | FS_DECRYPT = 0, |
| 67 | FS_ENCRYPT, |
| 68 | } fscrypt_direction_t; |
| 69 | |
| 70 | #define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001 |
| 71 | #define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002 |
| 72 | |
| Hyojun Kim | 63da420 | 2017-10-06 17:10:08 -0700 | [diff] [blame] | 73 | /* crypto.c */ |
| 74 | extern int fscrypt_initialize(unsigned int cop_flags); |
| 75 | extern struct workqueue_struct *fscrypt_read_workqueue; |
| 76 | extern int fscrypt_do_page_crypto(const struct inode *inode, |
| 77 | fscrypt_direction_t rw, u64 lblk_num, |
| 78 | struct page *src_page, |
| 79 | struct page *dest_page, |
| 80 | unsigned int len, unsigned int offs, |
| 81 | gfp_t gfp_flags); |
| 82 | extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx, |
| 83 | gfp_t gfp_flags); |
| 84 | |
| 85 | /* keyinfo.c */ |
| 86 | extern void __exit fscrypt_essiv_cleanup(void); |
| 87 | |
| 88 | #endif /* _FSCRYPT_PRIVATE_H */ |