1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
5 * These ioctls can be used on filesystems that support fscrypt. See the
6 * "User API" section of Documentation/filesystems/fscrypt.rst.
8 #ifndef _UAPI_LINUX_FSCRYPT_H
9 #define _UAPI_LINUX_FSCRYPT_H
11 #include <linux/ioctl.h>
12 #include <linux/types.h>
14 /* Encryption policy flags */
15 #define FSCRYPT_POLICY_FLAGS_PAD_4 0x00
16 #define FSCRYPT_POLICY_FLAGS_PAD_8 0x01
17 #define FSCRYPT_POLICY_FLAGS_PAD_16 0x02
18 #define FSCRYPT_POLICY_FLAGS_PAD_32 0x03
19 #define FSCRYPT_POLICY_FLAGS_PAD_MASK 0x03
20 #define FSCRYPT_POLICY_FLAG_DIRECT_KEY 0x04
21 #define FSCRYPT_POLICY_FLAG_IV_INO_LBLK_64 0x08
22 #define FSCRYPT_POLICY_FLAG_IV_INO_LBLK_32 0x10
24 /* Encryption algorithms */
25 #define FSCRYPT_MODE_AES_256_XTS 1
26 #define FSCRYPT_MODE_AES_256_CTS 4
27 #define FSCRYPT_MODE_AES_128_CBC 5
28 #define FSCRYPT_MODE_AES_128_CTS 6
29 #define FSCRYPT_MODE_ADIANTUM 9
30 #define FSCRYPT_MODE_AES_256_HCTR2 10
31 /* If adding a mode number > 10, update FSCRYPT_MODE_MAX in fscrypt_private.h */
34 * Legacy policy version; ad-hoc KDF and no key verification.
35 * For new encrypted directories, use fscrypt_policy_v2 instead.
37 * Careful: the .version field for this is actually 0, not 1.
39 #define FSCRYPT_POLICY_V1 0
40 #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8
41 struct fscrypt_policy_v1 {
43 __u8 contents_encryption_mode;
44 __u8 filenames_encryption_mode;
46 __u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
50 * Process-subscribed "logon" key description prefix and payload format.
51 * Deprecated; prefer FS_IOC_ADD_ENCRYPTION_KEY instead.
53 #define FSCRYPT_KEY_DESC_PREFIX "fscrypt:"
54 #define FSCRYPT_KEY_DESC_PREFIX_SIZE 8
55 #define FSCRYPT_MAX_KEY_SIZE 64
58 __u8 raw[FSCRYPT_MAX_KEY_SIZE];
63 * New policy version with HKDF and key verification (recommended).
65 #define FSCRYPT_POLICY_V2 2
66 #define FSCRYPT_KEY_IDENTIFIER_SIZE 16
67 struct fscrypt_policy_v2 {
69 __u8 contents_encryption_mode;
70 __u8 filenames_encryption_mode;
73 __u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
76 /* Struct passed to FS_IOC_GET_ENCRYPTION_POLICY_EX */
77 struct fscrypt_get_policy_ex_arg {
78 __u64 policy_size; /* input/output */
81 struct fscrypt_policy_v1 v1;
82 struct fscrypt_policy_v2 v2;
83 } policy; /* output */
87 * v1 policy keys are specified by an arbitrary 8-byte key "descriptor",
88 * matching fscrypt_policy_v1::master_key_descriptor.
90 #define FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR 1
93 * v2 policy keys are specified by a 16-byte key "identifier" which the kernel
94 * calculates as a cryptographic hash of the key itself,
95 * matching fscrypt_policy_v2::master_key_identifier.
97 #define FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER 2
100 * Specifies a key, either for v1 or v2 policies. This doesn't contain the
101 * actual key itself; this is just the "name" of the key.
103 struct fscrypt_key_specifier {
104 __u32 type; /* one of FSCRYPT_KEY_SPEC_TYPE_* */
107 __u8 __reserved[32]; /* reserve some extra space */
108 __u8 descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
109 __u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
114 * Payload of Linux keyring key of type "fscrypt-provisioning", referenced by
115 * fscrypt_add_key_arg::key_id as an alternative to fscrypt_add_key_arg::raw.
117 struct fscrypt_provisioning_key_payload {
123 /* Struct passed to FS_IOC_ADD_ENCRYPTION_KEY */
124 struct fscrypt_add_key_arg {
125 struct fscrypt_key_specifier key_spec;
132 /* Struct passed to FS_IOC_REMOVE_ENCRYPTION_KEY */
133 struct fscrypt_remove_key_arg {
134 struct fscrypt_key_specifier key_spec;
135 #define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_FILES_BUSY 0x00000001
136 #define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_OTHER_USERS 0x00000002
137 __u32 removal_status_flags; /* output */
141 /* Struct passed to FS_IOC_GET_ENCRYPTION_KEY_STATUS */
142 struct fscrypt_get_key_status_arg {
144 struct fscrypt_key_specifier key_spec;
148 #define FSCRYPT_KEY_STATUS_ABSENT 1
149 #define FSCRYPT_KEY_STATUS_PRESENT 2
150 #define FSCRYPT_KEY_STATUS_INCOMPLETELY_REMOVED 3
152 #define FSCRYPT_KEY_STATUS_FLAG_ADDED_BY_SELF 0x00000001
155 __u32 __out_reserved[13];
158 #define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy_v1)
159 #define FS_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
160 #define FS_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct fscrypt_policy_v1)
161 #define FS_IOC_GET_ENCRYPTION_POLICY_EX _IOWR('f', 22, __u8[9]) /* size + version */
162 #define FS_IOC_ADD_ENCRYPTION_KEY _IOWR('f', 23, struct fscrypt_add_key_arg)
163 #define FS_IOC_REMOVE_ENCRYPTION_KEY _IOWR('f', 24, struct fscrypt_remove_key_arg)
164 #define FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS _IOWR('f', 25, struct fscrypt_remove_key_arg)
165 #define FS_IOC_GET_ENCRYPTION_KEY_STATUS _IOWR('f', 26, struct fscrypt_get_key_status_arg)
166 #define FS_IOC_GET_ENCRYPTION_NONCE _IOR('f', 27, __u8[16])
168 /**********************************************************************/
170 /* old names; don't add anything new here! */
172 #define fscrypt_policy fscrypt_policy_v1
173 #define FS_KEY_DESCRIPTOR_SIZE FSCRYPT_KEY_DESCRIPTOR_SIZE
174 #define FS_POLICY_FLAGS_PAD_4 FSCRYPT_POLICY_FLAGS_PAD_4
175 #define FS_POLICY_FLAGS_PAD_8 FSCRYPT_POLICY_FLAGS_PAD_8
176 #define FS_POLICY_FLAGS_PAD_16 FSCRYPT_POLICY_FLAGS_PAD_16
177 #define FS_POLICY_FLAGS_PAD_32 FSCRYPT_POLICY_FLAGS_PAD_32
178 #define FS_POLICY_FLAGS_PAD_MASK FSCRYPT_POLICY_FLAGS_PAD_MASK
179 #define FS_POLICY_FLAG_DIRECT_KEY FSCRYPT_POLICY_FLAG_DIRECT_KEY
180 #define FS_POLICY_FLAGS_VALID 0x07 /* contains old flags only */
181 #define FS_ENCRYPTION_MODE_INVALID 0 /* never used */
182 #define FS_ENCRYPTION_MODE_AES_256_XTS FSCRYPT_MODE_AES_256_XTS
183 #define FS_ENCRYPTION_MODE_AES_256_GCM 2 /* never used */
184 #define FS_ENCRYPTION_MODE_AES_256_CBC 3 /* never used */
185 #define FS_ENCRYPTION_MODE_AES_256_CTS FSCRYPT_MODE_AES_256_CTS
186 #define FS_ENCRYPTION_MODE_AES_128_CBC FSCRYPT_MODE_AES_128_CBC
187 #define FS_ENCRYPTION_MODE_AES_128_CTS FSCRYPT_MODE_AES_128_CTS
188 #define FS_ENCRYPTION_MODE_SPECK128_256_XTS 7 /* removed */
189 #define FS_ENCRYPTION_MODE_SPECK128_256_CTS 8 /* removed */
190 #define FS_ENCRYPTION_MODE_ADIANTUM FSCRYPT_MODE_ADIANTUM
191 #define FS_KEY_DESC_PREFIX FSCRYPT_KEY_DESC_PREFIX
192 #define FS_KEY_DESC_PREFIX_SIZE FSCRYPT_KEY_DESC_PREFIX_SIZE
193 #define FS_MAX_KEY_SIZE FSCRYPT_MAX_KEY_SIZE
194 #endif /* !__KERNEL__ */
196 #endif /* _UAPI_LINUX_FSCRYPT_H */