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 /* If adding a mode number > 9, update FSCRYPT_MODE_MAX in fscrypt_private.h */ 31 32 /* 33 * Legacy policy version; ad-hoc KDF and no key verification. 34 * For new encrypted directories, use fscrypt_policy_v2 instead. 35 * 36 * Careful: the .version field for this is actually 0, not 1. 37 */ 38 #define FSCRYPT_POLICY_V1 0 39 #define FSCRYPT_KEY_DESCRIPTOR_SIZE 8 40 struct fscrypt_policy_v1 { 41 __u8 version; 42 __u8 contents_encryption_mode; 43 __u8 filenames_encryption_mode; 44 __u8 flags; 45 __u8 master_key_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; 46 }; 47 48 /* 49 * Process-subscribed "logon" key description prefix and payload format. 50 * Deprecated; prefer FS_IOC_ADD_ENCRYPTION_KEY instead. 51 */ 52 #define FSCRYPT_KEY_DESC_PREFIX "fscrypt:" 53 #define FSCRYPT_KEY_DESC_PREFIX_SIZE 8 54 #define FSCRYPT_MAX_KEY_SIZE 64 55 struct fscrypt_key { 56 __u32 mode; 57 __u8 raw[FSCRYPT_MAX_KEY_SIZE]; 58 __u32 size; 59 }; 60 61 /* 62 * New policy version with HKDF and key verification (recommended). 63 */ 64 #define FSCRYPT_POLICY_V2 2 65 #define FSCRYPT_KEY_IDENTIFIER_SIZE 16 66 struct fscrypt_policy_v2 { 67 __u8 version; 68 __u8 contents_encryption_mode; 69 __u8 filenames_encryption_mode; 70 __u8 flags; 71 __u8 __reserved[4]; 72 __u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; 73 }; 74 75 /* Struct passed to FS_IOC_GET_ENCRYPTION_POLICY_EX */ 76 struct fscrypt_get_policy_ex_arg { 77 __u64 policy_size; /* input/output */ 78 union { 79 __u8 version; 80 struct fscrypt_policy_v1 v1; 81 struct fscrypt_policy_v2 v2; 82 } policy; /* output */ 83 }; 84 85 /* 86 * v1 policy keys are specified by an arbitrary 8-byte key "descriptor", 87 * matching fscrypt_policy_v1::master_key_descriptor. 88 */ 89 #define FSCRYPT_KEY_SPEC_TYPE_DESCRIPTOR 1 90 91 /* 92 * v2 policy keys are specified by a 16-byte key "identifier" which the kernel 93 * calculates as a cryptographic hash of the key itself, 94 * matching fscrypt_policy_v2::master_key_identifier. 95 */ 96 #define FSCRYPT_KEY_SPEC_TYPE_IDENTIFIER 2 97 98 /* 99 * Specifies a key, either for v1 or v2 policies. This doesn't contain the 100 * actual key itself; this is just the "name" of the key. 101 */ 102 struct fscrypt_key_specifier { 103 __u32 type; /* one of FSCRYPT_KEY_SPEC_TYPE_* */ 104 __u32 __reserved; 105 union { 106 __u8 __reserved[32]; /* reserve some extra space */ 107 __u8 descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE]; 108 __u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]; 109 } u; 110 }; 111 112 /* 113 * Payload of Linux keyring key of type "fscrypt-provisioning", referenced by 114 * fscrypt_add_key_arg::key_id as an alternative to fscrypt_add_key_arg::raw. 115 */ 116 struct fscrypt_provisioning_key_payload { 117 __u32 type; 118 __u32 __reserved; 119 __u8 raw[]; 120 }; 121 122 /* Struct passed to FS_IOC_ADD_ENCRYPTION_KEY */ 123 struct fscrypt_add_key_arg { 124 struct fscrypt_key_specifier key_spec; 125 __u32 raw_size; 126 __u32 key_id; 127 __u32 __reserved[7]; 128 /* N.B.: "temporary" flag, not reserved upstream */ 129 #define __FSCRYPT_ADD_KEY_FLAG_HW_WRAPPED 0x00000001 130 __u32 __flags; 131 __u8 raw[]; 132 }; 133 134 /* Struct passed to FS_IOC_REMOVE_ENCRYPTION_KEY */ 135 struct fscrypt_remove_key_arg { 136 struct fscrypt_key_specifier key_spec; 137 #define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_FILES_BUSY 0x00000001 138 #define FSCRYPT_KEY_REMOVAL_STATUS_FLAG_OTHER_USERS 0x00000002 139 __u32 removal_status_flags; /* output */ 140 __u32 __reserved[5]; 141 }; 142 143 /* Struct passed to FS_IOC_GET_ENCRYPTION_KEY_STATUS */ 144 struct fscrypt_get_key_status_arg { 145 /* input */ 146 struct fscrypt_key_specifier key_spec; 147 __u32 __reserved[6]; 148 149 /* output */ 150 #define FSCRYPT_KEY_STATUS_ABSENT 1 151 #define FSCRYPT_KEY_STATUS_PRESENT 2 152 #define FSCRYPT_KEY_STATUS_INCOMPLETELY_REMOVED 3 153 __u32 status; 154 #define FSCRYPT_KEY_STATUS_FLAG_ADDED_BY_SELF 0x00000001 155 __u32 status_flags; 156 __u32 user_count; 157 __u32 __out_reserved[13]; 158 }; 159 160 #define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy_v1) 161 #define FS_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16]) 162 #define FS_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct fscrypt_policy_v1) 163 #define FS_IOC_GET_ENCRYPTION_POLICY_EX _IOWR('f', 22, __u8[9]) /* size + version */ 164 #define FS_IOC_ADD_ENCRYPTION_KEY _IOWR('f', 23, struct fscrypt_add_key_arg) 165 #define FS_IOC_REMOVE_ENCRYPTION_KEY _IOWR('f', 24, struct fscrypt_remove_key_arg) 166 #define FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS _IOWR('f', 25, struct fscrypt_remove_key_arg) 167 #define FS_IOC_GET_ENCRYPTION_KEY_STATUS _IOWR('f', 26, struct fscrypt_get_key_status_arg) 168 #define FS_IOC_GET_ENCRYPTION_NONCE _IOR('f', 27, __u8[16]) 169 170 /**********************************************************************/ 171 172 /* old names; don't add anything new here! */ 173 #ifndef __KERNEL__ 174 #define fscrypt_policy fscrypt_policy_v1 175 #define FS_KEY_DESCRIPTOR_SIZE FSCRYPT_KEY_DESCRIPTOR_SIZE 176 #define FS_POLICY_FLAGS_PAD_4 FSCRYPT_POLICY_FLAGS_PAD_4 177 #define FS_POLICY_FLAGS_PAD_8 FSCRYPT_POLICY_FLAGS_PAD_8 178 #define FS_POLICY_FLAGS_PAD_16 FSCRYPT_POLICY_FLAGS_PAD_16 179 #define FS_POLICY_FLAGS_PAD_32 FSCRYPT_POLICY_FLAGS_PAD_32 180 #define FS_POLICY_FLAGS_PAD_MASK FSCRYPT_POLICY_FLAGS_PAD_MASK 181 #define FS_POLICY_FLAG_DIRECT_KEY FSCRYPT_POLICY_FLAG_DIRECT_KEY 182 #define FS_POLICY_FLAGS_VALID 0x07 /* contains old flags only */ 183 #define FS_ENCRYPTION_MODE_INVALID 0 /* never used */ 184 #define FS_ENCRYPTION_MODE_AES_256_XTS FSCRYPT_MODE_AES_256_XTS 185 #define FS_ENCRYPTION_MODE_AES_256_GCM 2 /* never used */ 186 #define FS_ENCRYPTION_MODE_AES_256_CBC 3 /* never used */ 187 #define FS_ENCRYPTION_MODE_AES_256_CTS FSCRYPT_MODE_AES_256_CTS 188 #define FS_ENCRYPTION_MODE_AES_128_CBC FSCRYPT_MODE_AES_128_CBC 189 #define FS_ENCRYPTION_MODE_AES_128_CTS FSCRYPT_MODE_AES_128_CTS 190 #define FS_ENCRYPTION_MODE_SPECK128_256_XTS 7 /* removed */ 191 #define FS_ENCRYPTION_MODE_SPECK128_256_CTS 8 /* removed */ 192 #define FS_ENCRYPTION_MODE_ADIANTUM FSCRYPT_MODE_ADIANTUM 193 #define FS_KEY_DESC_PREFIX FSCRYPT_KEY_DESC_PREFIX 194 #define FS_KEY_DESC_PREFIX_SIZE FSCRYPT_KEY_DESC_PREFIX_SIZE 195 #define FS_MAX_KEY_SIZE FSCRYPT_MAX_KEY_SIZE 196 #endif /* !__KERNEL__ */ 197 198 #endif /* _UAPI_LINUX_FSCRYPT_H */ 199