[mirror_ubuntu-artful-kernel.git] / fs / crypto / fscrypt_private.h

/*
 * fscrypt_private.h
 *
 * Copyright (C) 2015, Google, Inc.
 *
 * This contains encryption key functions.
 *
 * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
 */

#ifndef _FSCRYPT_PRIVATE_H
#define _FSCRYPT_PRIVATE_H

#include <linux/fscrypt_supp.h>
#include <crypto/hash.h>

/* Encryption parameters */
#define FS_IV_SIZE			16
#define FS_AES_128_ECB_KEY_SIZE		16
#define FS_AES_128_CBC_KEY_SIZE		16
#define FS_AES_128_CTS_KEY_SIZE		16
#define FS_AES_256_GCM_KEY_SIZE		32
#define FS_AES_256_CBC_KEY_SIZE		32
#define FS_AES_256_CTS_KEY_SIZE		32
#define FS_AES_256_XTS_KEY_SIZE		64

#define FS_KEY_DERIVATION_NONCE_SIZE		16

/**
 * Encryption context for inode
 *
 * Protector format:
 *  1 byte: Protector format (1 = this version)
 *  1 byte: File contents encryption mode
 *  1 byte: File names encryption mode
 *  1 byte: Flags
 *  8 bytes: Master Key descriptor
 *  16 bytes: Encryption Key derivation nonce
 */
struct fscrypt_context {
	u8 format;
	u8 contents_encryption_mode;
	u8 filenames_encryption_mode;
	u8 flags;
	u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
	u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
} __packed;

#define FS_ENCRYPTION_CONTEXT_FORMAT_V1		1

/*
 * A pointer to this structure is stored in the file system's in-core
 * representation of an inode.
 */
struct fscrypt_info {
	u8 ci_data_mode;
	u8 ci_filename_mode;
	u8 ci_flags;
	struct crypto_skcipher *ci_ctfm;
	struct crypto_cipher *ci_essiv_tfm;
	u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
};

typedef enum {
	FS_DECRYPT = 0,
	FS_ENCRYPT,
} fscrypt_direction_t;

#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL		0x00000001
#define FS_CTX_HAS_BOUNCE_BUFFER_FL		0x00000002

struct fscrypt_completion_result {
	struct completion completion;
	int res;
};

#define DECLARE_FS_COMPLETION_RESULT(ecr) \
	struct fscrypt_completion_result ecr = { \
		COMPLETION_INITIALIZER_ONSTACK((ecr).completion), 0 }


/* crypto.c */
extern int fscrypt_initialize(unsigned int cop_flags);
extern struct workqueue_struct *fscrypt_read_workqueue;
extern int fscrypt_do_page_crypto(const struct inode *inode,
				  fscrypt_direction_t rw, u64 lblk_num,
				  struct page *src_page,
				  struct page *dest_page,
				  unsigned int len, unsigned int offs,
				  gfp_t gfp_flags);
extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
					      gfp_t gfp_flags);

/* keyinfo.c */
extern void __exit fscrypt_essiv_cleanup(void);

#endif /* _FSCRYPT_PRIVATE_H */
Commit	Line	Data
3325bea5 TT	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
46f47e48	14	#include <linux/fscrypt_supp.h>
b7e7cf7a	15	#include <crypto/hash.h>
3325bea5	16
cc4e0df0	17	/* Encryption parameters */
b7e7cf7a	18	#define FS_IV_SIZE 16
cc4e0df0	19	#define FS_AES_128_ECB_KEY_SIZE 16
b7e7cf7a DW	20	#define FS_AES_128_CBC_KEY_SIZE 16
b7e7cf7a DW	21	#define FS_AES_128_CTS_KEY_SIZE 16
cc4e0df0 TT	22	#define FS_AES_256_GCM_KEY_SIZE 32
	23	#define FS_AES_256_CBC_KEY_SIZE 32
	24	#define FS_AES_256_CTS_KEY_SIZE 32
	25	#define FS_AES_256_XTS_KEY_SIZE 64
cc4e0df0 TT	26
	27	#define FS_KEY_DERIVATION_NONCE_SIZE 16
	28
	29	/**
	30	* Encryption context for inode
	31	*
	32	* Protector format:
	33	* 1 byte: Protector format (1 = this version)
	34	* 1 byte: File contents encryption mode
	35	* 1 byte: File names encryption mode
	36	* 1 byte: Flags
	37	* 8 bytes: Master Key descriptor
	38	* 16 bytes: Encryption Key derivation nonce
	39	*/
	40	struct fscrypt_context {
	41	u8 format;
	42	u8 contents_encryption_mode;
	43	u8 filenames_encryption_mode;
	44	u8 flags;
	45	u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
	46	u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
	47	} __packed;
	48
	49	#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
	50
cc4e0df0 TT	51	/*
	52	* A pointer to this structure is stored in the file system's in-core
	53	* representation of an inode.
	54	*/
	55	struct fscrypt_info {
	56	u8 ci_data_mode;
	57	u8 ci_filename_mode;
	58	u8 ci_flags;
	59	struct crypto_skcipher *ci_ctfm;
b7e7cf7a	60	struct crypto_cipher *ci_essiv_tfm;
cc4e0df0 TT	61	u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
	62	};
	63
58ae7468 RW	64	typedef enum {
	65	FS_DECRYPT = 0,
	66	FS_ENCRYPT,
	67	} fscrypt_direction_t;
	68
cc4e0df0	69	#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
6a34e4d2	70	#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
cc4e0df0 TT	71
	72	struct fscrypt_completion_result {
	73	struct completion completion;
	74	int res;
	75	};
	76
	77	#define DECLARE_FS_COMPLETION_RESULT(ecr) \
	78	struct fscrypt_completion_result ecr = { \
b14c8e6a	79	COMPLETION_INITIALIZER_ONSTACK((ecr).completion), 0 }
cc4e0df0 TT	80
cc4e0df0 TT	81
b98701df	82	/* crypto.c */
58ae7468 RW	83	extern int fscrypt_initialize(unsigned int cop_flags);
	84	extern struct workqueue_struct *fscrypt_read_workqueue;
	85	extern int fscrypt_do_page_crypto(const struct inode *inode,
	86	fscrypt_direction_t rw, u64 lblk_num,
	87	struct page *src_page,
	88	struct page *dest_page,
	89	unsigned int len, unsigned int offs,
	90	gfp_t gfp_flags);
	91	extern struct page fscrypt_alloc_bounce_page(struct fscrypt_ctx ctx,
	92	gfp_t gfp_flags);
b98701df	93
b7e7cf7a DW	94	/* keyinfo.c */
	95	extern void __exit fscrypt_essiv_cleanup(void);
	96
3325bea5	97	#endif /* _FSCRYPT_PRIVATE_H */