152 lines
3.8 KiB
C
152 lines
3.8 KiB
C
/*
|
|
* linux/fs/f2fs/f2fs_crypto.h
|
|
*
|
|
* Copied from linux/fs/ext4/ext4_crypto.h
|
|
*
|
|
* Copyright (C) 2015, Google, Inc.
|
|
*
|
|
* This contains encryption header content for f2fs
|
|
*
|
|
* Written by Michael Halcrow, 2015.
|
|
* Modified by Jaegeuk Kim, 2015.
|
|
*/
|
|
#ifndef _F2FS_CRYPTO_H
|
|
#define _F2FS_CRYPTO_H
|
|
|
|
#include <linux/fs.h>
|
|
|
|
#define F2FS_KEY_DESCRIPTOR_SIZE 8
|
|
|
|
/* Policy provided via an ioctl on the topmost directory */
|
|
struct f2fs_encryption_policy {
|
|
char version;
|
|
char contents_encryption_mode;
|
|
char filenames_encryption_mode;
|
|
char flags;
|
|
char master_key_descriptor[F2FS_KEY_DESCRIPTOR_SIZE];
|
|
} __attribute__((__packed__));
|
|
|
|
#define F2FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
|
|
#define F2FS_KEY_DERIVATION_NONCE_SIZE 16
|
|
|
|
#define F2FS_POLICY_FLAGS_PAD_4 0x00
|
|
#define F2FS_POLICY_FLAGS_PAD_8 0x01
|
|
#define F2FS_POLICY_FLAGS_PAD_16 0x02
|
|
#define F2FS_POLICY_FLAGS_PAD_32 0x03
|
|
#define F2FS_POLICY_FLAGS_PAD_MASK 0x03
|
|
#define F2FS_POLICY_FLAGS_VALID 0x03
|
|
|
|
/**
|
|
* 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 f2fs_encryption_context {
|
|
char format;
|
|
char contents_encryption_mode;
|
|
char filenames_encryption_mode;
|
|
char flags;
|
|
char master_key_descriptor[F2FS_KEY_DESCRIPTOR_SIZE];
|
|
char nonce[F2FS_KEY_DERIVATION_NONCE_SIZE];
|
|
} __attribute__((__packed__));
|
|
|
|
/* Encryption parameters */
|
|
#define F2FS_XTS_TWEAK_SIZE 16
|
|
#define F2FS_AES_128_ECB_KEY_SIZE 16
|
|
#define F2FS_AES_256_GCM_KEY_SIZE 32
|
|
#define F2FS_AES_256_CBC_KEY_SIZE 32
|
|
#define F2FS_AES_256_CTS_KEY_SIZE 32
|
|
#define F2FS_AES_256_XTS_KEY_SIZE 64
|
|
#define F2FS_MAX_KEY_SIZE 64
|
|
|
|
#define F2FS_KEY_DESC_PREFIX "f2fs:"
|
|
#define F2FS_KEY_DESC_PREFIX_SIZE 5
|
|
|
|
struct f2fs_encryption_key {
|
|
__u32 mode;
|
|
char raw[F2FS_MAX_KEY_SIZE];
|
|
__u32 size;
|
|
} __attribute__((__packed__));
|
|
|
|
struct f2fs_crypt_info {
|
|
char ci_data_mode;
|
|
char ci_filename_mode;
|
|
char ci_flags;
|
|
struct crypto_ablkcipher *ci_ctfm;
|
|
struct key *ci_keyring_key;
|
|
char ci_master_key[F2FS_KEY_DESCRIPTOR_SIZE];
|
|
};
|
|
|
|
#define F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
|
|
#define F2FS_WRITE_PATH_FL 0x00000002
|
|
|
|
struct f2fs_crypto_ctx {
|
|
union {
|
|
struct {
|
|
struct page *bounce_page; /* Ciphertext page */
|
|
struct page *control_page; /* Original page */
|
|
} w;
|
|
struct {
|
|
struct bio *bio;
|
|
struct work_struct work;
|
|
} r;
|
|
struct list_head free_list; /* Free list */
|
|
};
|
|
char flags; /* Flags */
|
|
};
|
|
|
|
struct f2fs_completion_result {
|
|
struct completion completion;
|
|
int res;
|
|
};
|
|
|
|
#define DECLARE_F2FS_COMPLETION_RESULT(ecr) \
|
|
struct f2fs_completion_result ecr = { \
|
|
COMPLETION_INITIALIZER((ecr).completion), 0 }
|
|
|
|
static inline int f2fs_encryption_key_size(int mode)
|
|
{
|
|
switch (mode) {
|
|
case F2FS_ENCRYPTION_MODE_AES_256_XTS:
|
|
return F2FS_AES_256_XTS_KEY_SIZE;
|
|
case F2FS_ENCRYPTION_MODE_AES_256_GCM:
|
|
return F2FS_AES_256_GCM_KEY_SIZE;
|
|
case F2FS_ENCRYPTION_MODE_AES_256_CBC:
|
|
return F2FS_AES_256_CBC_KEY_SIZE;
|
|
case F2FS_ENCRYPTION_MODE_AES_256_CTS:
|
|
return F2FS_AES_256_CTS_KEY_SIZE;
|
|
default:
|
|
BUG();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#define F2FS_FNAME_NUM_SCATTER_ENTRIES 4
|
|
#define F2FS_CRYPTO_BLOCK_SIZE 16
|
|
#define F2FS_FNAME_CRYPTO_DIGEST_SIZE 32
|
|
|
|
/**
|
|
* For encrypted symlinks, the ciphertext length is stored at the beginning
|
|
* of the string in little-endian format.
|
|
*/
|
|
struct f2fs_encrypted_symlink_data {
|
|
__le16 len;
|
|
char encrypted_path[1];
|
|
} __attribute__((__packed__));
|
|
|
|
/**
|
|
* This function is used to calculate the disk space required to
|
|
* store a filename of length l in encrypted symlink format.
|
|
*/
|
|
static inline u32 encrypted_symlink_data_len(u32 l)
|
|
{
|
|
return (l + sizeof(struct f2fs_encrypted_symlink_data) - 1);
|
|
}
|
|
#endif /* _F2FS_CRYPTO_H */
|