keymaster_defs.h revision 4c19a3af3535eb3442ff7cc4235420baf16322b7
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ANDROID_HARDWARE_KEYMASTER_DEFS_H 18#define ANDROID_HARDWARE_KEYMASTER_DEFS_H 19 20#include <stdint.h> 21#include <stdlib.h> 22#include <string.h> 23 24#ifndef __cplusplus 25extern "C" { 26#endif // __cplusplus 27 28/** 29 * Authorization tags each have an associated type. This enumeration facilitates tagging each with 30 * a type, by using the high four bits (of an implied 32-bit unsigned enum value) to specify up to 31 * 16 data types. These values are ORed with tag IDs to generate the final tag ID values. 32 */ 33typedef enum { 34 KM_INVALID = 0 << 28, /* Invalid type, used to designate a tag as uninitialized */ 35 KM_ENUM = 1 << 28, 36 KM_ENUM_REP = 2 << 28, /* Repeatable enumeration value. */ 37 KM_INT = 3 << 28, 38 KM_INT_REP = 4 << 28, /* Repeatable integer value */ 39 KM_LONG = 5 << 28, 40 KM_DATE = 6 << 28, 41 KM_BOOL = 7 << 28, 42 KM_BIGNUM = 8 << 28, 43 KM_BYTES = 9 << 28, 44 KM_LONG_REP = 10 << 28, /* Repeatable long value */ 45} keymaster_tag_type_t; 46 47typedef enum { 48 KM_TAG_INVALID = KM_INVALID | 0, 49 50 /* 51 * Tags that must be semantically enforced by hardware and software implementations. 52 */ 53 54 /* Crypto parameters */ 55 KM_TAG_PURPOSE = KM_ENUM_REP | 1, /* keymaster_purpose_t. */ 56 KM_TAG_ALGORITHM = KM_ENUM | 2, /* keymaster_algorithm_t. */ 57 KM_TAG_KEY_SIZE = KM_INT | 3, /* Key size in bits. */ 58 KM_TAG_BLOCK_MODE = KM_ENUM_REP | 4, /* keymaster_block_mode_t. */ 59 KM_TAG_DIGEST = KM_ENUM_REP | 5, /* keymaster_digest_t. */ 60 KM_TAG_PADDING = KM_ENUM_REP | 6, /* keymaster_padding_t. */ 61 KM_TAG_RETURN_UNAUTHED = KM_BOOL | 7, /* Allow AEAD decryption to return plaintext before it has 62 been authenticated. WARNING: Not recommended. */ 63 KM_TAG_CALLER_NONCE = KM_BOOL | 8, /* Allow caller to specify nonce or IV. */ 64 65 /* Algorithm-specific. */ 66 KM_TAG_RSA_PUBLIC_EXPONENT = KM_LONG | 200, /* Defaults to 2^16+1 */ 67 68 /* Other hardware-enforced. */ 69 KM_TAG_BLOB_USAGE_REQUIREMENTS = KM_ENUM | 301, /* keymaster_key_blob_usage_requirements_t */ 70 KM_TAG_BOOTLOADER_ONLY = KM_BOOL | 302, /* Usable only by bootloader */ 71 72 /* 73 * Tags that should be semantically enforced by hardware if possible and will otherwise be 74 * enforced by software (keystore). 75 */ 76 77 /* Key validity period */ 78 KM_TAG_ACTIVE_DATETIME = KM_DATE | 400, /* Start of validity */ 79 KM_TAG_ORIGINATION_EXPIRE_DATETIME = KM_DATE | 401, /* Date when new "messages" should no 80 longer be created. */ 81 KM_TAG_USAGE_EXPIRE_DATETIME = KM_DATE | 402, /* Date when existing "messages" should no 82 longer be trusted. */ 83 KM_TAG_MIN_SECONDS_BETWEEN_OPS = KM_INT | 403, /* Minimum elapsed time between 84 cryptographic operations with the key. */ 85 KM_TAG_MAX_USES_PER_BOOT = KM_INT | 404, /* Number of times the key can be used per 86 boot. */ 87 88 /* User authentication */ 89 KM_TAG_ALL_USERS = KM_BOOL | 500, /* If key is usable by all users. */ 90 KM_TAG_USER_ID = KM_INT | 501, /* ID of authorized user. Disallowed if 91 KM_TAG_ALL_USERS is present. */ 92 KM_TAG_USER_SECURE_ID = KM_LONG_REP | 502, /* Secure ID of authorized user or authenticator(s). 93 Disallowed if KM_TAG_ALL_USERS or 94 KM_TAG_NO_AUTH_REQUIRED is present. */ 95 KM_TAG_NO_AUTH_REQUIRED = KM_BOOL | 503, /* If key is usable without authentication. */ 96 KM_TAG_USER_AUTH_TYPE = KM_ENUM | 504, /* Bitmask of authenticator types allowed when 97 * KM_TAG_USER_SECURE_ID contains a secure user ID, 98 * rather than a secure authenticator ID. Defined in 99 * hw_authenticator_type_t in hw_auth_token.h. */ 100 KM_TAG_AUTH_TIMEOUT = KM_INT | 505, /* Required freshness of user authentication for 101 private/secret key operations, in seconds. 102 Public key operations require no authentication. 103 If absent, authentication is required for every 104 use. Authentication state is lost when the 105 device is powered off. */ 106 107 /* Application access control */ 108 KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* If key is usable by all applications. */ 109 KM_TAG_APPLICATION_ID = KM_BYTES | 601, /* ID of authorized application. Disallowed if 110 KM_TAG_ALL_APPLICATIONS is present. */ 111 112 /* 113 * Semantically unenforceable tags, either because they have no specific meaning or because 114 * they're informational only. 115 */ 116 KM_TAG_APPLICATION_DATA = KM_BYTES | 700, /* Data provided by authorized application. */ 117 KM_TAG_CREATION_DATETIME = KM_DATE | 701, /* Key creation time */ 118 KM_TAG_ORIGIN = KM_ENUM | 702, /* keymaster_key_origin_t. */ 119 KM_TAG_ROLLBACK_RESISTANT = KM_BOOL | 703, /* Whether key is rollback-resistant. */ 120 KM_TAG_ROOT_OF_TRUST = KM_BYTES | 704, /* Root of trust ID. Empty array means usable by all 121 roots. */ 122 123 /* Tags used only to provide data to or receive data from operations */ 124 KM_TAG_ASSOCIATED_DATA = KM_BYTES | 1000, /* Used to provide associated data for AEAD modes. */ 125 KM_TAG_NONCE = KM_BYTES | 1001, /* Nonce or Initialization Vector */ 126 KM_TAG_CHUNK_LENGTH = KM_INT | 1002, /* AEAD mode chunk size, in bytes. 0 means no limit, 127 which requires KM_TAG_RETURN_UNAUTHED. */ 128 KM_TAG_AUTH_TOKEN = KM_BYTES | 1003, /* Authentication token that proves secure user 129 authentication has been performed. Structure 130 defined in hw_auth_token_t in hw_auth_token.h. */ 131 KM_TAG_MAC_LENGTH = KM_INT | 1004, /* MAC or AEAD authentication tag length in bits. */ 132} keymaster_tag_t; 133 134/** 135 * Algorithms that may be provided by keymaster implementations. Those that must be provided by all 136 * implementations are tagged as "required". 137 */ 138typedef enum { 139 /* Asymmetric algorithms. */ 140 KM_ALGORITHM_RSA = 1, 141 // KM_ALGORITHM_DSA = 2, -- Removed, do not re-use value 2. 142 KM_ALGORITHM_EC = 3, 143 144 /* Block ciphers algorithms */ 145 KM_ALGORITHM_AES = 32, 146 147 /* MAC algorithms */ 148 KM_ALGORITHM_HMAC = 128, 149} keymaster_algorithm_t; 150 151/** 152 * Symmetric block cipher modes provided by keymaster implementations. 153 */ 154typedef enum { 155 /* Unauthenticated modes, usable only for encryption/decryption and not generally recommended 156 * except for compatibility with existing other protocols. */ 157 KM_MODE_ECB = 1, 158 KM_MODE_CBC = 2, 159 KM_MODE_CTR = 3, 160 161 /* Authenticated modes, usable for encryption/decryption and signing/verification. Recommended 162 * over unauthenticated modes for all purposes. */ 163 KM_MODE_GCM = 32, 164} keymaster_block_mode_t; 165 166/** 167 * Padding modes that may be applied to plaintext for encryption operations. This list includes 168 * padding modes for both symmetric and asymmetric algorithms. Note that implementations should not 169 * provide all possible combinations of algorithm and padding, only the 170 * cryptographically-appropriate pairs. 171 */ 172typedef enum { 173 KM_PAD_NONE = 1, /* deprecated */ 174 KM_PAD_RSA_OAEP = 2, 175 KM_PAD_RSA_PSS = 3, 176 KM_PAD_RSA_PKCS1_1_5_ENCRYPT = 4, 177 KM_PAD_RSA_PKCS1_1_5_SIGN = 5, 178 KM_PAD_PKCS7 = 64, 179} keymaster_padding_t; 180 181/** 182 * Digests provided by keymaster implementations. 183 */ 184typedef enum { 185 KM_DIGEST_NONE = 0, 186 KM_DIGEST_MD5 = 1, /* Optional, may not be implemented in hardware, will be handled in software 187 * if needed. */ 188 KM_DIGEST_SHA1 = 2, 189 KM_DIGEST_SHA_2_224 = 3, 190 KM_DIGEST_SHA_2_256 = 4, 191 KM_DIGEST_SHA_2_384 = 5, 192 KM_DIGEST_SHA_2_512 = 6, 193} keymaster_digest_t; 194 195/** 196 * The origin of a key (or pair), i.e. where it was generated. Note that KM_TAG_ORIGIN can be found 197 * in either the hardware-enforced or software-enforced list for a key, indicating whether the key 198 * is hardware or software-based. Specifically, a key with KM_ORIGIN_GENERATED in the 199 * hardware-enforced list is guaranteed never to have existed outide the secure hardware. 200 */ 201typedef enum { 202 KM_ORIGIN_GENERATED = 0, /* Generated in keymaster */ 203 KM_ORIGIN_IMPORTED = 2, /* Imported, origin unknown */ 204 KM_ORIGIN_UNKNOWN = 3, /* Keymaster did not record origin. This value can only be seen on 205 * keys in a keymaster0 implementation. The keymaster0 adapter uses 206 * this value to document the fact that it is unkown whether the key 207 * was generated inside or imported into keymaster. */ 208} keymaster_key_origin_t; 209 210/** 211 * Usability requirements of key blobs. This defines what system functionality must be available 212 * for the key to function. For example, key "blobs" which are actually handles referencing 213 * encrypted key material stored in the file system cannot be used until the file system is 214 * available, and should have BLOB_REQUIRES_FILE_SYSTEM. Other requirements entries will be added 215 * as needed for implementations. This type is new in 0_4. 216 */ 217typedef enum { 218 KM_BLOB_STANDALONE = 0, 219 KM_BLOB_REQUIRES_FILE_SYSTEM = 1, 220} keymaster_key_blob_usage_requirements_t; 221 222/** 223 * Possible purposes of a key (or pair). This type is new in 0_4. 224 */ 225typedef enum { 226 KM_PURPOSE_ENCRYPT = 0, 227 KM_PURPOSE_DECRYPT = 1, 228 KM_PURPOSE_SIGN = 2, 229 KM_PURPOSE_VERIFY = 3, 230} keymaster_purpose_t; 231 232typedef struct { 233 const uint8_t* data; 234 size_t data_length; 235} keymaster_blob_t; 236 237typedef struct { 238 keymaster_tag_t tag; 239 union { 240 uint32_t enumerated; /* KM_ENUM and KM_ENUM_REP */ 241 bool boolean; /* KM_BOOL */ 242 uint32_t integer; /* KM_INT and KM_INT_REP */ 243 uint64_t long_integer; /* KM_LONG */ 244 uint64_t date_time; /* KM_DATE */ 245 keymaster_blob_t blob; /* KM_BIGNUM and KM_BYTES*/ 246 }; 247} keymaster_key_param_t; 248 249typedef struct { 250 keymaster_key_param_t* params; /* may be NULL if length == 0 */ 251 size_t length; 252} keymaster_key_param_set_t; 253 254/** 255 * Parameters that define a key's characteristics, including authorized modes of usage and access 256 * control restrictions. The parameters are divided into two categories, those that are enforced by 257 * secure hardware, and those that are not. For a software-only keymaster implementation the 258 * enforced array must NULL. Hardware implementations must enforce everything in the enforced 259 * array. 260 */ 261typedef struct { 262 keymaster_key_param_set_t hw_enforced; 263 keymaster_key_param_set_t sw_enforced; 264} keymaster_key_characteristics_t; 265 266typedef struct { 267 const uint8_t* key_material; 268 size_t key_material_size; 269} keymaster_key_blob_t; 270 271/** 272 * Formats for key import and export. At present, only asymmetric key import/export is supported. 273 * In the future this list will expand greatly to accommodate asymmetric key import/export. 274 */ 275typedef enum { 276 KM_KEY_FORMAT_X509 = 0, /* for public key export */ 277 KM_KEY_FORMAT_PKCS8 = 1, /* for asymmetric key pair import */ 278 KM_KEY_FORMAT_RAW = 3, /* for symmetric key import */ 279} keymaster_key_format_t; 280 281/** 282 * The keymaster operation API consists of begin, update, finish and abort. This is the type of the 283 * handle used to tie the sequence of calls together. A 64-bit value is used because it's important 284 * that handles not be predictable. Implementations must use strong random numbers for handle 285 * values. 286 */ 287typedef uint64_t keymaster_operation_handle_t; 288 289typedef enum { 290 KM_ERROR_OK = 0, 291 KM_ERROR_ROOT_OF_TRUST_ALREADY_SET = -1, 292 KM_ERROR_UNSUPPORTED_PURPOSE = -2, 293 KM_ERROR_INCOMPATIBLE_PURPOSE = -3, 294 KM_ERROR_UNSUPPORTED_ALGORITHM = -4, 295 KM_ERROR_INCOMPATIBLE_ALGORITHM = -5, 296 KM_ERROR_UNSUPPORTED_KEY_SIZE = -6, 297 KM_ERROR_UNSUPPORTED_BLOCK_MODE = -7, 298 KM_ERROR_INCOMPATIBLE_BLOCK_MODE = -8, 299 KM_ERROR_UNSUPPORTED_MAC_LENGTH = -9, 300 KM_ERROR_UNSUPPORTED_PADDING_MODE = -10, 301 KM_ERROR_INCOMPATIBLE_PADDING_MODE = -11, 302 KM_ERROR_UNSUPPORTED_DIGEST = -12, 303 KM_ERROR_INCOMPATIBLE_DIGEST = -13, 304 KM_ERROR_INVALID_EXPIRATION_TIME = -14, 305 KM_ERROR_INVALID_USER_ID = -15, 306 KM_ERROR_INVALID_AUTHORIZATION_TIMEOUT = -16, 307 KM_ERROR_UNSUPPORTED_KEY_FORMAT = -17, 308 KM_ERROR_INCOMPATIBLE_KEY_FORMAT = -18, 309 KM_ERROR_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM = -19, /* For PKCS8 & PKCS12 */ 310 KM_ERROR_UNSUPPORTED_KEY_VERIFICATION_ALGORITHM = -20, /* For PKCS8 & PKCS12 */ 311 KM_ERROR_INVALID_INPUT_LENGTH = -21, 312 KM_ERROR_KEY_EXPORT_OPTIONS_INVALID = -22, 313 KM_ERROR_DELEGATION_NOT_ALLOWED = -23, 314 KM_ERROR_KEY_NOT_YET_VALID = -24, 315 KM_ERROR_KEY_EXPIRED = -25, 316 KM_ERROR_KEY_USER_NOT_AUTHENTICATED = -26, 317 KM_ERROR_OUTPUT_PARAMETER_NULL = -27, 318 KM_ERROR_INVALID_OPERATION_HANDLE = -28, 319 KM_ERROR_INSUFFICIENT_BUFFER_SPACE = -29, 320 KM_ERROR_VERIFICATION_FAILED = -30, 321 KM_ERROR_TOO_MANY_OPERATIONS = -31, 322 KM_ERROR_UNEXPECTED_NULL_POINTER = -32, 323 KM_ERROR_INVALID_KEY_BLOB = -33, 324 KM_ERROR_IMPORTED_KEY_NOT_ENCRYPTED = -34, 325 KM_ERROR_IMPORTED_KEY_DECRYPTION_FAILED = -35, 326 KM_ERROR_IMPORTED_KEY_NOT_SIGNED = -36, 327 KM_ERROR_IMPORTED_KEY_VERIFICATION_FAILED = -37, 328 KM_ERROR_INVALID_ARGUMENT = -38, 329 KM_ERROR_UNSUPPORTED_TAG = -39, 330 KM_ERROR_INVALID_TAG = -40, 331 KM_ERROR_MEMORY_ALLOCATION_FAILED = -41, 332 KM_ERROR_IMPORT_PARAMETER_MISMATCH = -44, 333 KM_ERROR_SECURE_HW_ACCESS_DENIED = -45, 334 KM_ERROR_OPERATION_CANCELLED = -46, 335 KM_ERROR_CONCURRENT_ACCESS_CONFLICT = -47, 336 KM_ERROR_SECURE_HW_BUSY = -48, 337 KM_ERROR_SECURE_HW_COMMUNICATION_FAILED = -49, 338 KM_ERROR_UNSUPPORTED_EC_FIELD = -50, 339 KM_ERROR_MISSING_NONCE = -51, 340 KM_ERROR_INVALID_NONCE = -52, 341 KM_ERROR_UNSUPPORTED_CHUNK_LENGTH = -53, 342 KM_ERROR_CALLER_NONCE_PROHIBITED = -55, 343 344 KM_ERROR_UNIMPLEMENTED = -100, 345 KM_ERROR_VERSION_MISMATCH = -101, 346 347 /* Additional error codes may be added by implementations, but implementers should coordinate 348 * with Google to avoid code collision. */ 349 KM_ERROR_UNKNOWN_ERROR = -1000, 350} keymaster_error_t; 351 352/* Convenience functions for manipulating keymaster tag types */ 353 354static inline keymaster_tag_type_t keymaster_tag_get_type(keymaster_tag_t tag) { 355 return (keymaster_tag_type_t)(tag & (0xF << 28)); 356} 357 358static inline uint32_t keymaster_tag_mask_type(keymaster_tag_t tag) { 359 return tag & 0x0FFFFFFF; 360} 361 362static inline bool keymaster_tag_type_repeatable(keymaster_tag_type_t type) { 363 switch (type) { 364 case KM_INT_REP: 365 case KM_ENUM_REP: 366 return true; 367 default: 368 return false; 369 } 370} 371 372static inline bool keymaster_tag_repeatable(keymaster_tag_t tag) { 373 return keymaster_tag_type_repeatable(keymaster_tag_get_type(tag)); 374} 375 376/* Convenience functions for manipulating keymaster_key_param_t structs */ 377 378inline keymaster_key_param_t keymaster_param_enum(keymaster_tag_t tag, uint32_t value) { 379 // assert(keymaster_tag_get_type(tag) == KM_ENUM || keymaster_tag_get_type(tag) == KM_ENUM_REP); 380 keymaster_key_param_t param; 381 memset(¶m, 0, sizeof(param)); 382 param.tag = tag; 383 param.enumerated = value; 384 return param; 385} 386 387inline keymaster_key_param_t keymaster_param_int(keymaster_tag_t tag, uint32_t value) { 388 // assert(keymaster_tag_get_type(tag) == KM_INT || keymaster_tag_get_type(tag) == KM_INT_REP); 389 keymaster_key_param_t param; 390 memset(¶m, 0, sizeof(param)); 391 param.tag = tag; 392 param.integer = value; 393 return param; 394} 395 396inline keymaster_key_param_t keymaster_param_long(keymaster_tag_t tag, uint64_t value) { 397 // assert(keymaster_tag_get_type(tag) == KM_LONG); 398 keymaster_key_param_t param; 399 memset(¶m, 0, sizeof(param)); 400 param.tag = tag; 401 param.long_integer = value; 402 return param; 403} 404 405inline keymaster_key_param_t keymaster_param_blob(keymaster_tag_t tag, const uint8_t* bytes, 406 size_t bytes_len) { 407 // assert(keymaster_tag_get_type(tag) == KM_BYTES || keymaster_tag_get_type(tag) == KM_BIGNUM); 408 keymaster_key_param_t param; 409 memset(¶m, 0, sizeof(param)); 410 param.tag = tag; 411 param.blob.data = (uint8_t*)bytes; 412 param.blob.data_length = bytes_len; 413 return param; 414} 415 416inline keymaster_key_param_t keymaster_param_bool(keymaster_tag_t tag) { 417 // assert(keymaster_tag_get_type(tag) == KM_BOOL); 418 keymaster_key_param_t param; 419 memset(¶m, 0, sizeof(param)); 420 param.tag = tag; 421 param.boolean = true; 422 return param; 423} 424 425inline keymaster_key_param_t keymaster_param_date(keymaster_tag_t tag, uint64_t value) { 426 // assert(keymaster_tag_get_type(tag) == KM_DATE); 427 keymaster_key_param_t param; 428 memset(¶m, 0, sizeof(param)); 429 param.tag = tag; 430 param.date_time = value; 431 return param; 432} 433 434#define KEYMASTER_SIMPLE_COMPARE(a, b) (a < b) ? -1 : ((a > b) ? 1 : 0) 435inline int keymaster_param_compare(const keymaster_key_param_t* a, const keymaster_key_param_t* b) { 436 int retval = KEYMASTER_SIMPLE_COMPARE(a->tag, b->tag); 437 if (retval != 0) 438 return retval; 439 440 switch (keymaster_tag_get_type(a->tag)) { 441 case KM_INVALID: 442 case KM_BOOL: 443 return 0; 444 case KM_ENUM: 445 case KM_ENUM_REP: 446 return KEYMASTER_SIMPLE_COMPARE(a->enumerated, b->enumerated); 447 case KM_INT: 448 case KM_INT_REP: 449 return KEYMASTER_SIMPLE_COMPARE(a->integer, b->integer); 450 case KM_LONG: 451 case KM_LONG_REP: 452 return KEYMASTER_SIMPLE_COMPARE(a->long_integer, b->long_integer); 453 case KM_DATE: 454 return KEYMASTER_SIMPLE_COMPARE(a->date_time, b->date_time); 455 case KM_BIGNUM: 456 case KM_BYTES: 457 // Handle the empty cases. 458 if (a->blob.data_length != 0 && b->blob.data_length == 0) 459 return -1; 460 if (a->blob.data_length == 0 && b->blob.data_length == 0) 461 return 0; 462 if (a->blob.data_length == 0 && b->blob.data_length > 0) 463 return 1; 464 465 retval = memcmp(a->blob.data, b->blob.data, a->blob.data_length < b->blob.data_length 466 ? a->blob.data_length 467 : b->blob.data_length); 468 if (retval != 0) 469 return retval; 470 else if (a->blob.data_length != b->blob.data_length) { 471 // Equal up to the common length; longer one is larger. 472 if (a->blob.data_length < b->blob.data_length) 473 return -1; 474 if (a->blob.data_length > b->blob.data_length) 475 return 1; 476 }; 477 } 478 479 return 0; 480} 481#undef KEYMASTER_SIMPLE_COMPARE 482 483inline void keymaster_free_param_values(keymaster_key_param_t* param, size_t param_count) { 484 while (param_count-- > 0) { 485 switch (keymaster_tag_get_type(param->tag)) { 486 case KM_BIGNUM: 487 case KM_BYTES: 488 free((void*)param->blob.data); 489 param->blob.data = NULL; 490 break; 491 default: 492 // NOP 493 break; 494 } 495 ++param; 496 } 497} 498 499inline void keymaster_free_param_set(keymaster_key_param_set_t* set) { 500 if (set) { 501 keymaster_free_param_values(set->params, set->length); 502 free(set->params); 503 set->params = NULL; 504 } 505} 506 507inline void keymaster_free_characteristics(keymaster_key_characteristics_t* characteristics) { 508 if (characteristics) { 509 keymaster_free_param_set(&characteristics->hw_enforced); 510 keymaster_free_param_set(&characteristics->sw_enforced); 511 } 512} 513 514#ifndef __cplusplus 515} // extern "C" 516#endif // __cplusplus 517 518#endif // ANDROID_HARDWARE_KEYMASTER_DEFS_H 519