diff options
| -rw-r--r-- | Documentation/filesystems/fscrypt.rst | 40 | ||||
| -rw-r--r-- | include/uapi/linux/fscrypt.h | 65 |
2 files changed, 62 insertions, 43 deletions
diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 82efa41b0e6c..d60b885c4024 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -225,9 +225,10 @@ a little endian number, except that: is encrypted with AES-256 where the AES-256 key is the SHA-256 hash of the file's data encryption key. -- In the "direct key" configuration (FS_POLICY_FLAG_DIRECT_KEY set in - the fscrypt_policy), the file's nonce is also appended to the IV. - Currently this is only allowed with the Adiantum encryption mode. +- In the "direct key" configuration (FSCRYPT_POLICY_FLAG_DIRECT_KEY + set in the fscrypt_policy), the file's nonce is also appended to the + IV. Currently this is only allowed with the Adiantum encryption + mode. Filenames encryption -------------------- @@ -274,14 +275,14 @@ empty directory or verifies that a directory or regular file already has the specified encryption policy. It takes in a pointer to a :c:type:`struct fscrypt_policy`, defined as follows:: - #define FS_KEY_DESCRIPTOR_SIZE 8 + #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 struct fscrypt_policy { __u8 version; __u8 contents_encryption_mode; __u8 filenames_encryption_mode; __u8 flags; - __u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE]; + __u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; }; This structure must be initialized as follows: @@ -289,19 +290,18 @@ This structure must be initialized as follows: - ``version`` must be 0. - ``contents_encryption_mode`` and ``filenames_encryption_mode`` must - be set to constants from ``<linux/fs.h>`` which identify the - encryption modes to use. If unsure, use - FS_ENCRYPTION_MODE_AES_256_XTS (1) for ``contents_encryption_mode`` - and FS_ENCRYPTION_MODE_AES_256_CTS (4) for - ``filenames_encryption_mode``. + be set to constants from ``<linux/fscrypt.h>`` which identify the + encryption modes to use. If unsure, use FSCRYPT_MODE_AES_256_XTS + (1) for ``contents_encryption_mode`` and FSCRYPT_MODE_AES_256_CTS + (4) for ``filenames_encryption_mode``. -- ``flags`` must contain a value from ``<linux/fs.h>`` which +- ``flags`` must contain a value from ``<linux/fscrypt.h>`` which identifies the amount of NUL-padding to use when encrypting - filenames. If unsure, use FS_POLICY_FLAGS_PAD_32 (0x3). - In addition, if the chosen encryption modes are both - FS_ENCRYPTION_MODE_ADIANTUM, this can contain - FS_POLICY_FLAG_DIRECT_KEY to specify that the master key should be - used directly, without key derivation. + filenames. If unsure, use FSCRYPT_POLICY_FLAGS_PAD_32 (0x3). In + addition, if the chosen encryption modes are both + FSCRYPT_MODE_ADIANTUM, this can contain + FSCRYPT_POLICY_FLAG_DIRECT_KEY to specify that the master key should + be used directly, without key derivation. - ``master_key_descriptor`` specifies how to find the master key in the keyring; see `Adding keys`_. It is up to userspace to choose a @@ -401,11 +401,11 @@ followed by the 16-character lower case hex representation of the ``master_key_descriptor`` that was set in the encryption policy. The key payload must conform to the following structure:: - #define FS_MAX_KEY_SIZE 64 + #define FSCRYPT_MAX_KEY_SIZE 64 struct fscrypt_key { u32 mode; - u8 raw[FS_MAX_KEY_SIZE]; + u8 raw[FSCRYPT_MAX_KEY_SIZE]; u32 size; }; @@ -574,7 +574,7 @@ much confusion if an encryption policy were to be added to or removed from anything other than an empty directory.) The struct is defined as follows:: - #define FS_KEY_DESCRIPTOR_SIZE 8 + #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 #define FS_KEY_DERIVATION_NONCE_SIZE 16 struct fscrypt_context { @@ -582,7 +582,7 @@ as follows:: u8 contents_encryption_mode; u8 filenames_encryption_mode; u8 flags; - u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE]; + u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE]; }; diff --git a/include/uapi/linux/fscrypt.h b/include/uapi/linux/fscrypt.h index 26f6d2c19afd..674b0452ef57 100644 --- a/include/uapi/linux/fscrypt.h +++ b/include/uapi/linux/fscrypt.h @@ -10,35 +10,30 @@ #include <linux/types.h> -#define FS_KEY_DESCRIPTOR_SIZE 8 +#define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 /* Encryption policy flags */ -#define FS_POLICY_FLAGS_PAD_4 0x00 -#define FS_POLICY_FLAGS_PAD_8 0x01 -#define FS_POLICY_FLAGS_PAD_16 0x02 -#define FS_POLICY_FLAGS_PAD_32 0x03 -#define FS_POLICY_FLAGS_PAD_MASK 0x03 -#define FS_POLICY_FLAG_DIRECT_KEY 0x04 /* use master key directly */ -#define FS_POLICY_FLAGS_VALID 0x07 +#define FSCRYPT_POLICY_FLAGS_PAD_4 0x00 +#define FSCRYPT_POLICY_FLAGS_PAD_8 0x01 +#define FSCRYPT_POLICY_FLAGS_PAD_16 0x02 +#define FSCRYPT_POLICY_FLAGS_PAD_32 0x03 +#define FSCRYPT_POLICY_FLAGS_PAD_MASK 0x03 +#define FSCRYPT_POLICY_FLAG_DIRECT_KEY 0x04 /* use master key directly */ +#define FSCRYPT_POLICY_FLAGS_VALID 0x07 /* Encryption algorithms */ -#define FS_ENCRYPTION_MODE_INVALID 0 -#define FS_ENCRYPTION_MODE_AES_256_XTS 1 -#define FS_ENCRYPTION_MODE_AES_256_GCM 2 -#define FS_ENCRYPTION_MODE_AES_256_CBC 3 -#define FS_ENCRYPTION_MODE_AES_256_CTS 4 -#define FS_ENCRYPTION_MODE_AES_128_CBC 5 -#define FS_ENCRYPTION_MODE_AES_128_CTS 6 -#define FS_ENCRYPTION_MODE_SPECK128_256_XTS 7 /* Removed, do not use. */ -#define FS_ENCRYPTION_MODE_SPECK128_256_CTS 8 /* Removed, do not use. */ -#define FS_ENCRYPTION_MODE_ADIANTUM 9 +#define FSCRYPT_MODE_AES_256_XTS 1 +#define FSCRYPT_MODE_AES_256_CTS 4 +#define FSCRYPT_MODE_AES_128_CBC 5 +#define FSCRYPT_MODE_AES_128_CTS 6 +#define FSCRYPT_MODE_ADIANTUM 9 struct fscrypt_policy { __u8 version; __u8 contents_encryption_mode; __u8 filenames_encryption_mode; __u8 flags; - __u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE]; + __u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; }; #define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy) @@ -46,16 +41,40 @@ struct fscrypt_policy { #define FS_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct fscrypt_policy) /* Parameters for passing an encryption key into the kernel keyring */ -#define FS_KEY_DESC_PREFIX "fscrypt:" -#define FS_KEY_DESC_PREFIX_SIZE 8 +#define FSCRYPT_KEY_DESC_PREFIX "fscrypt:" +#define FSCRYPT_KEY_DESC_PREFIX_SIZE 8 /* Structure that userspace passes to the kernel keyring */ -#define FS_MAX_KEY_SIZE 64 +#define FSCRYPT_MAX_KEY_SIZE 64 struct fscrypt_key { __u32 mode; - __u8 raw[FS_MAX_KEY_SIZE]; + __u8 raw[FSCRYPT_MAX_KEY_SIZE]; __u32 size; }; +/**********************************************************************/ + +/* old names; don't add anything new here! */ +#define FS_KEY_DESCRIPTOR_SIZE FSCRYPT_KEY_DESCRIPTOR_SIZE +#define FS_POLICY_FLAGS_PAD_4 FSCRYPT_POLICY_FLAGS_PAD_4 +#define FS_POLICY_FLAGS_PAD_8 FSCRYPT_POLICY_FLAGS_PAD_8 +#define FS_POLICY_FLAGS_PAD_16 FSCRYPT_POLICY_FLAGS_PAD_16 +#define FS_POLICY_FLAGS_PAD_32 FSCRYPT_POLICY_FLAGS_PAD_32 +#define FS_POLICY_FLAGS_PAD_MASK FSCRYPT_POLICY_FLAGS_PAD_MASK +#define FS_POLICY_FLAG_DIRECT_KEY FSCRYPT_POLICY_FLAG_DIRECT_KEY +#define FS_POLICY_FLAGS_VALID FSCRYPT_POLICY_FLAGS_VALID +#define FS_ENCRYPTION_MODE_INVALID 0 /* never used */ +#define FS_ENCRYPTION_MODE_AES_256_XTS FSCRYPT_MODE_AES_256_XTS +#define FS_ENCRYPTION_MODE_AES_256_GCM 2 /* never used */ +#define FS_ENCRYPTION_MODE_AES_256_CBC 3 /* never used */ +#define FS_ENCRYPTION_MODE_AES_256_CTS FSCRYPT_MODE_AES_256_CTS +#define FS_ENCRYPTION_MODE_AES_128_CBC FSCRYPT_MODE_AES_128_CBC +#define FS_ENCRYPTION_MODE_AES_128_CTS FSCRYPT_MODE_AES_128_CTS +#define FS_ENCRYPTION_MODE_SPECK128_256_XTS 7 /* removed */ +#define FS_ENCRYPTION_MODE_SPECK128_256_CTS 8 /* removed */ +#define FS_ENCRYPTION_MODE_ADIANTUM FSCRYPT_MODE_ADIANTUM +#define FS_KEY_DESC_PREFIX FSCRYPT_KEY_DESC_PREFIX +#define FS_KEY_DESC_PREFIX_SIZE FSCRYPT_KEY_DESC_PREFIX_SIZE +#define FS_MAX_KEY_SIZE FSCRYPT_MAX_KEY_SIZE #endif /* _UAPI_LINUX_FSCRYPT_H */ |