1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 /* 3 * fscrypt user API 4 * 5 * These ioctls can be used on filesystems that support fscrypt. See the 6 * "User API" section of Documentation/filesystems/fscrypt.rst. 7 */ 8 #ifndef _UAPI_LINUX_FSCRYPT_H 9 #define _UAPI_LINUX_FSCRYPT_H 10 11 #include <linux/ioctl.h> 12 #include <linux/types.h> 13 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 23 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 */ 32 33 /* 34 * Legacy policy version; ad-hoc KDF and no key verification. 35 * For new encrypted directories, use fscrypt_policy_v2 instead. 36 * 37 * Careful: the .version field for this is actually 0, not 1. 38 */ 39 #define FSCRYPT_POLICY_V1 0 40 #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 41 struct fscrypt_policy_v1 { 42 __u8 version; 43 __u8 contents_encryption_mode; 44 __u8 filenames_encryption_mode; 45 __u8 flags; 46 __u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; 47 }; 48 49 /* 50 * Process-subscribed "logon" key description prefix and payload format. 51 * Deprecated; prefer FS_IOC_ADD_ENCRYPTION_KEY instead. 52 */ 53 #define FSCRYPT_KEY_DESC_PREFIX "fscrypt:" 54 #define FSCRYPT_KEY_DESC_PREFIX_SIZE 8 55 #define FSCRYPT_MAX_KEY_SIZE 64 56 struct fscrypt_key { 57 __u32 mode; 58 __u8 raw[FSCRYPT_MAX_KEY_SIZE]; 59 __u32 size; 60 }; 61 62 /* 63 * New policy version with HKDF and key verification (recommended). 64 */ 65 #define FSCRYPT_POLICY_V2 2 66 #define FSCRYPT_KEY_IDENTIFIER_SIZE 16 67 struct fscrypt_policy_v2 { 68 __u8 version; 69 __u8 contents_encryption_mode; 70 __u8 filenames_encryption_mode; 71 __u8 flags; 72 __u8 __reserved[4]; 73 __u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; 74 }; 75 76 /* Struct passed to FS_IOC_GET_ENCRYPTION_POLICY_EX */ 77 struct fscrypt_get_policy_ex_arg { 78 __u64 policy_size; /* input/output */ 79 union { 80 __u8 version; 81 struct fscrypt_policy_v1 v1; 82 struct fscrypt_policy_v2 v2; 83 } policy; /* output */ 84 }; 85 86 /* 87 * v1 policy keys are specified by an arbitrary 8-byte key "descriptor", 88 * matching fscrypt_policy_v1::master_key_descriptor. 89 */ 90 #define FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR 1 91 92 /* 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. 96 */ 97 #define FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER 2 98 99 /* 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. 102 */ 103 struct fscrypt_key_specifier { 104 __u32 type; /* one of FSCRYPT_KEY_SPEC_TYPE_* */ 105 __u32 __reserved; 106 union { 107 __u8 __reserved[32]; /* reserve some extra space */ 108 __u8 descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; 109 __u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; 110 } u; 111 }; 112 113 /* 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. 116 */ 117 struct fscrypt_provisioning_key_payload { 118 __u32 type; 119 __u32 __reserved; 120 __u8 raw[]; 121 }; 122 123 /* Struct passed to FS_IOC_ADD_ENCRYPTION_KEY */ 124 struct fscrypt_add_key_arg { 125 struct fscrypt_key_specifier key_spec; 126 __u32 raw_size; 127 __u32 key_id; 128 __u32 __reserved[8]; 129 __u8 raw[]; 130 }; 131 132 /* 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 */ 138 __u32 __reserved[5]; 139 }; 140 141 /* Struct passed to FS_IOC_GET_ENCRYPTION_KEY_STATUS */ 142 struct fscrypt_get_key_status_arg { 143 /* input */ 144 struct fscrypt_key_specifier key_spec; 145 __u32 __reserved[6]; 146 147 /* output */ 148 #define FSCRYPT_KEY_STATUS_ABSENT 1 149 #define FSCRYPT_KEY_STATUS_PRESENT 2 150 #define FSCRYPT_KEY_STATUS_INCOMPLETELY_REMOVED 3 151 __u32 status; 152 #define FSCRYPT_KEY_STATUS_FLAG_ADDED_BY_SELF 0x00000001 153 __u32 status_flags; 154 __u32 user_count; 155 __u32 __out_reserved[13]; 156 }; 157 158 #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]) 167 168 /**********************************************************************/ 169 170 /* old names; don't add anything new here! */ 171 #ifndef __KERNEL__ 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__ */ 195 196 #endif /* _UAPI_LINUX_FSCRYPT_H */ 197