290502bee2
When the userspace messaging (for the less common case of userspace key wrap/unwrap via ecryptfsd) is not needed, allow eCryptfs to build with it removed. This saves on kernel code size and reduces potential attack surface by removing the /dev/ecryptfs node. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
106 lines
3.8 KiB
C
106 lines
3.8 KiB
C
#ifndef _LINUX_ECRYPTFS_H
|
|
#define _LINUX_ECRYPTFS_H
|
|
|
|
/* Version verification for shared data structures w/ userspace */
|
|
#define ECRYPTFS_VERSION_MAJOR 0x00
|
|
#define ECRYPTFS_VERSION_MINOR 0x04
|
|
#define ECRYPTFS_SUPPORTED_FILE_VERSION 0x03
|
|
/* These flags indicate which features are supported by the kernel
|
|
* module; userspace tools such as the mount helper read the feature
|
|
* bits from a sysfs handle in order to determine how to behave. */
|
|
#define ECRYPTFS_VERSIONING_PASSPHRASE 0x00000001
|
|
#define ECRYPTFS_VERSIONING_PUBKEY 0x00000002
|
|
#define ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH 0x00000004
|
|
#define ECRYPTFS_VERSIONING_POLICY 0x00000008
|
|
#define ECRYPTFS_VERSIONING_XATTR 0x00000010
|
|
#define ECRYPTFS_VERSIONING_MULTKEY 0x00000020
|
|
#define ECRYPTFS_VERSIONING_DEVMISC 0x00000040
|
|
#define ECRYPTFS_VERSIONING_HMAC 0x00000080
|
|
#define ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION 0x00000100
|
|
#define ECRYPTFS_VERSIONING_GCM 0x00000200
|
|
#define ECRYPTFS_MAX_PASSWORD_LENGTH 64
|
|
#define ECRYPTFS_MAX_PASSPHRASE_BYTES ECRYPTFS_MAX_PASSWORD_LENGTH
|
|
#define ECRYPTFS_SALT_SIZE 8
|
|
#define ECRYPTFS_SALT_SIZE_HEX (ECRYPTFS_SALT_SIZE*2)
|
|
/* The original signature size is only for what is stored on disk; all
|
|
* in-memory representations are expanded hex, so it better adapted to
|
|
* be passed around or referenced on the command line */
|
|
#define ECRYPTFS_SIG_SIZE 8
|
|
#define ECRYPTFS_SIG_SIZE_HEX (ECRYPTFS_SIG_SIZE*2)
|
|
#define ECRYPTFS_PASSWORD_SIG_SIZE ECRYPTFS_SIG_SIZE_HEX
|
|
#define ECRYPTFS_MAX_KEY_BYTES 64
|
|
#define ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES 512
|
|
#define ECRYPTFS_FILE_VERSION 0x03
|
|
#define ECRYPTFS_MAX_PKI_NAME_BYTES 16
|
|
|
|
#define RFC2440_CIPHER_DES3_EDE 0x02
|
|
#define RFC2440_CIPHER_CAST_5 0x03
|
|
#define RFC2440_CIPHER_BLOWFISH 0x04
|
|
#define RFC2440_CIPHER_AES_128 0x07
|
|
#define RFC2440_CIPHER_AES_192 0x08
|
|
#define RFC2440_CIPHER_AES_256 0x09
|
|
#define RFC2440_CIPHER_TWOFISH 0x0a
|
|
#define RFC2440_CIPHER_CAST_6 0x0b
|
|
|
|
#define RFC2440_CIPHER_RSA 0x01
|
|
|
|
/**
|
|
* For convenience, we may need to pass around the encrypted session
|
|
* key between kernel and userspace because the authentication token
|
|
* may not be extractable. For example, the TPM may not release the
|
|
* private key, instead requiring the encrypted data and returning the
|
|
* decrypted data.
|
|
*/
|
|
struct ecryptfs_session_key {
|
|
#define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_DECRYPT 0x00000001
|
|
#define ECRYPTFS_USERSPACE_SHOULD_TRY_TO_ENCRYPT 0x00000002
|
|
#define ECRYPTFS_CONTAINS_DECRYPTED_KEY 0x00000004
|
|
#define ECRYPTFS_CONTAINS_ENCRYPTED_KEY 0x00000008
|
|
u32 flags;
|
|
u32 encrypted_key_size;
|
|
u32 decrypted_key_size;
|
|
u8 encrypted_key[ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES];
|
|
u8 decrypted_key[ECRYPTFS_MAX_KEY_BYTES];
|
|
};
|
|
|
|
struct ecryptfs_password {
|
|
u32 password_bytes;
|
|
s32 hash_algo;
|
|
u32 hash_iterations;
|
|
u32 session_key_encryption_key_bytes;
|
|
#define ECRYPTFS_PERSISTENT_PASSWORD 0x01
|
|
#define ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET 0x02
|
|
u32 flags;
|
|
/* Iterated-hash concatenation of salt and passphrase */
|
|
u8 session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES];
|
|
u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
|
|
/* Always in expanded hex */
|
|
u8 salt[ECRYPTFS_SALT_SIZE];
|
|
};
|
|
|
|
enum ecryptfs_token_types {ECRYPTFS_PASSWORD, ECRYPTFS_PRIVATE_KEY};
|
|
|
|
struct ecryptfs_private_key {
|
|
u32 key_size;
|
|
u32 data_len;
|
|
u8 signature[ECRYPTFS_PASSWORD_SIG_SIZE + 1];
|
|
char pki_type[ECRYPTFS_MAX_PKI_NAME_BYTES + 1];
|
|
u8 data[];
|
|
};
|
|
|
|
/* May be a password or a private key */
|
|
struct ecryptfs_auth_tok {
|
|
u16 version; /* 8-bit major and 8-bit minor */
|
|
u16 token_type;
|
|
#define ECRYPTFS_ENCRYPT_ONLY 0x00000001
|
|
u32 flags;
|
|
struct ecryptfs_session_key session_key;
|
|
u8 reserved[32];
|
|
union {
|
|
struct ecryptfs_password password;
|
|
struct ecryptfs_private_key private_key;
|
|
} token;
|
|
} __attribute__ ((packed));
|
|
|
|
#endif /* _LINUX_ECRYPTFS_H */
|