On Mon, Oct 23, 2017 at 02:40:34PM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> There are going to be more filesystem encryption definitions added, and
> we don't want to use a disproportionate amount of space in <linux/fs.h>
> for filesystem encryption stuff. So move the fscrypt definitions to a
> new header <linux/fscrypt.h>.
>
> For compatibility with existing userspace programs which may be
> including <linux/fs.h>, <linux/fs.h> still includes the new header.
> (It's debatable whether we really need this, though; the filesystem
> encryption API is new enough that most if not all programs that are
> using it have to declare it themselves anyway.)
>
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Reviewed-by: Michael Halcrow <mhalcrow@xxxxxxxxxx>
> ---
> include/linux/fscrypt.h | 2 +-
> include/uapi/linux/fs.h | 50 +++--------------------------------------
> include/uapi/linux/fscrypt.h | 53 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 57 insertions(+), 48 deletions(-)
> create mode 100644 include/uapi/linux/fscrypt.h
>
> diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
> index 53437bfdfcbc..f7aa7d62e235 100644
> --- a/include/linux/fscrypt.h
> +++ b/include/linux/fscrypt.h
> @@ -19,7 +19,7 @@
> #include <linux/bio.h>
> #include <linux/dcache.h>
> #include <crypto/skcipher.h>
> -#include <uapi/linux/fs.h>
> +#include <uapi/linux/fscrypt.h>
>
> #define FS_CRYPTO_BLOCK_SIZE 16
>
> diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
> index 56235dddea7d..6ecd3ee9960c 100644
> --- a/include/uapi/linux/fs.h
> +++ b/include/uapi/linux/fs.h
> @@ -12,6 +12,9 @@
> #include <linux/limits.h>
> #include <linux/ioctl.h>
> #include <linux/types.h>
> +#ifndef __KERNEL__
> +#include <linux/fscrypt.h>
> +#endif
>
> /*
> * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
> @@ -253,53 +256,6 @@ struct fsxattr {
> #define FS_IOC_FSGETXATTR _IOR ('X', 31, struct fsxattr)
> #define FS_IOC_FSSETXATTR _IOW ('X', 32, struct fsxattr)
>
> -/*
> - * File system encryption support
> - */
> -/* Policy provided via an ioctl on the topmost directory */
> -#define FS_KEY_DESCRIPTOR_SIZE 8
> -
> -#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_FLAGS_VALID 0x03
> -
> -/* 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
> -
> -struct fscrypt_policy {
> - __u8 version;
> - __u8 contents_encryption_mode;
> - __u8 filenames_encryption_mode;
> - __u8 flags;
> - __u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
> -};
> -
> -#define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy)
> -#define FS_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
> -#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
> -
> -/* Structure that userspace passes to the kernel keyring */
> -#define FS_MAX_KEY_SIZE 64
> -
> -struct fscrypt_key {
> - __u32 mode;
> - __u8 raw[FS_MAX_KEY_SIZE];
> - __u32 size;
> -};
> -
> /*
> * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
> *
> diff --git a/include/uapi/linux/fscrypt.h b/include/uapi/linux/fscrypt.h
> new file mode 100644
> index 000000000000..c09209fc42ea
> --- /dev/null
> +++ b/include/uapi/linux/fscrypt.h
> @@ -0,0 +1,53 @@
> +#ifndef _UAPI_LINUX_FSCRYPT_H
> +#define _UAPI_LINUX_FSCRYPT_H
> +
> +#include <linux/types.h>
> +
> +/*
> + * File system encryption support
> + */
> +/* Policy provided via an ioctl on the topmost directory */
> +#define FS_KEY_DESCRIPTOR_SIZE 8
> +
> +#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_FLAGS_VALID 0x03
> +
> +/* 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
> +
> +struct fscrypt_policy {
> + __u8 version;
> + __u8 contents_encryption_mode;
> + __u8 filenames_encryption_mode;
> + __u8 flags;
> + __u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
> +};
> +
> +#define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy)
> +#define FS_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
> +#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
> +
> +/* Structure that userspace passes to the kernel keyring */
> +#define FS_MAX_KEY_SIZE 64
> +
> +struct fscrypt_key {
> + __u32 mode;
> + __u8 raw[FS_MAX_KEY_SIZE];
> + __u32 size;
> +};
> +
> +#endif /* _UAPI_LINUX_FSCRYPT_H */
> --
> 2.15.0.rc0.271.g36b669edcc-goog
>
