[mirror_ubuntu-bionic-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>

/* Encryption parameters */
#define FS_XTS_TWEAK_SIZE		16
#define FS_AES_128_ECB_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;
	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);

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