diff options
Diffstat (limited to 'fs/crypto/fscrypt_private.h')
-rw-r--r-- | fs/crypto/fscrypt_private.h | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h new file mode 100644 index 000000000000..aeab032d7d35 --- /dev/null +++ b/fs/crypto/fscrypt_private.h @@ -0,0 +1,93 @@ +/* + * 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/fscrypto.h> + +#define FS_FNAME_CRYPTO_DIGEST_SIZE 32 + +/* 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_MAX_KEY_SIZE 64 + +#define FS_KEY_DESC_PREFIX "fscrypt:" +#define FS_KEY_DESC_PREFIX_SIZE 8 + +#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 + +/* This is passed in from userspace into the kernel keyring */ +struct fscrypt_key { + u32 mode; + u8 raw[FS_MAX_KEY_SIZE]; + u32 size; +} __packed; + +/* + * 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 key *ci_keyring_key; + u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE]; +}; + +#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((ecr).completion), 0 } + + +/* crypto.c */ +int fscrypt_initialize(unsigned int cop_flags); + +/* keyinfo.c */ +extern int fscrypt_get_crypt_info(struct inode *); + +#endif /* _FSCRYPT_PRIVATE_H */ |