[linux-block.git] / fs / crypto / fscrypt_private.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * 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
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
3325bea5 TT	2	/*
	3	* fscrypt_private.h
	4	*
	5	* Copyright (C) 2015, Google, Inc.
	6	*
	7	* This contains encryption key functions.
	8	*
	9	* Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
	10	*/
	11
	12	#ifndef _FSCRYPT_PRIVATE_H
	13	#define _FSCRYPT_PRIVATE_H
	14
46f47e48	15	#include <linux/fscrypt_supp.h>
b7e7cf7a	16	#include <crypto/hash.h>
3325bea5	17
cc4e0df0	18	/* Encryption parameters */
b7e7cf7a	19	#define FS_IV_SIZE 16
cc4e0df0	20	#define FS_AES_128_ECB_KEY_SIZE 16
b7e7cf7a DW	21	#define FS_AES_128_CBC_KEY_SIZE 16
b7e7cf7a DW	22	#define FS_AES_128_CTS_KEY_SIZE 16
cc4e0df0 TT	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
cc4e0df0 TT	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
cc4e0df0 TT	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;
b7e7cf7a	61	struct crypto_cipher *ci_essiv_tfm;
cc4e0df0 TT	62	u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
	63	};
	64
58ae7468 RW	65	typedef enum {
	66	FS_DECRYPT = 0,
	67	FS_ENCRYPT,
	68	} fscrypt_direction_t;
	69
cc4e0df0	70	#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
6a34e4d2	71	#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
cc4e0df0 TT	72
	73	struct fscrypt_completion_result {
	74	struct completion completion;
	75	int res;
	76	};
	77
	78	#define DECLARE_FS_COMPLETION_RESULT(ecr) \
	79	struct fscrypt_completion_result ecr = { \
b14c8e6a	80	COMPLETION_INITIALIZER_ONSTACK((ecr).completion), 0 }
cc4e0df0 TT	81
cc4e0df0 TT	82
b98701df	83	/* crypto.c */
58ae7468 RW	84	extern int fscrypt_initialize(unsigned int cop_flags);
	85	extern struct workqueue_struct *fscrypt_read_workqueue;
	86	extern int fscrypt_do_page_crypto(const struct inode *inode,
	87	fscrypt_direction_t rw, u64 lblk_num,
	88	struct page *src_page,
	89	struct page *dest_page,
	90	unsigned int len, unsigned int offs,
	91	gfp_t gfp_flags);
	92	extern struct page fscrypt_alloc_bounce_page(struct fscrypt_ctx ctx,
	93	gfp_t gfp_flags);
b98701df	94
b7e7cf7a DW	95	/* keyinfo.c */
	96	extern void __exit fscrypt_essiv_cleanup(void);
	97
3325bea5	98	#endif /* _FSCRYPT_PRIVATE_H */