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      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 #ifdef __cplusplus
     25 extern "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  */
     33 typedef 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_UINT = 3 << 28,
     38     KM_UINT_REP = 4 << 28, /* Repeatable integer value */
     39     KM_ULONG = 5 << 28,
     40     KM_DATE = 6 << 28,
     41     KM_BOOL = 7 << 28,
     42     KM_BIGNUM = 8 << 28,
     43     KM_BYTES = 9 << 28,
     44     KM_ULONG_REP = 10 << 28, /* Repeatable long value */
     45 } keymaster_tag_type_t;
     46 
     47 typedef 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_UINT | 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_CALLER_NONCE = KM_BOOL | 7,   /* Allow caller to specify nonce or IV. */
     62     KM_TAG_MIN_MAC_LENGTH = KM_UINT | 8, /* Minimum length of MAC or AEAD authentication tag in
     63                                           * bits. */
     64     KM_TAG_KDF = KM_ENUM_REP | 9,        /* keymaster_kdf_t (keymaster2) */
     65     KM_TAG_EC_CURVE = KM_ENUM | 10,      /* keymaster_ec_curve_t (keymaster2) */
     66 
     67     /* Algorithm-specific. */
     68     KM_TAG_RSA_PUBLIC_EXPONENT = KM_ULONG | 200,
     69     KM_TAG_ECIES_SINGLE_HASH_MODE = KM_BOOL | 201, /* Whether the ephemeral public key is fed into
     70                                                     * the KDF */
     71     KM_TAG_INCLUDE_UNIQUE_ID = KM_BOOL | 202,      /* If true, attestation certificates for this key
     72                                                     * will contain an application-scoped and
     73                                                     * time-bounded device-unique ID. (keymaster2) */
     74 
     75     /* Other hardware-enforced. */
     76     KM_TAG_BLOB_USAGE_REQUIREMENTS = KM_ENUM | 301, /* keymaster_key_blob_usage_requirements_t */
     77     KM_TAG_BOOTLOADER_ONLY = KM_BOOL | 302,         /* Usable only by bootloader */
     78 
     79     /*
     80      * Tags that should be semantically enforced by hardware if possible and will otherwise be
     81      * enforced by software (keystore).
     82      */
     83 
     84     /* Key validity period */
     85     KM_TAG_ACTIVE_DATETIME = KM_DATE | 400,             /* Start of validity */
     86     KM_TAG_ORIGINATION_EXPIRE_DATETIME = KM_DATE | 401, /* Date when new "messages" should no
     87                                                            longer be created. */
     88     KM_TAG_USAGE_EXPIRE_DATETIME = KM_DATE | 402,       /* Date when existing "messages" should no
     89                                                            longer be trusted. */
     90     KM_TAG_MIN_SECONDS_BETWEEN_OPS = KM_UINT | 403,     /* Minimum elapsed time between
     91                                                            cryptographic operations with the key. */
     92     KM_TAG_MAX_USES_PER_BOOT = KM_UINT | 404,           /* Number of times the key can be used per
     93                                                            boot. */
     94 
     95     /* User authentication */
     96     KM_TAG_ALL_USERS = KM_BOOL | 500,           /* Reserved for future use -- ignore */
     97     KM_TAG_USER_ID = KM_UINT | 501,             /* Reserved for future use -- ignore */
     98     KM_TAG_USER_SECURE_ID = KM_ULONG_REP | 502, /* Secure ID of authorized user or authenticator(s).
     99                                                    Disallowed if KM_TAG_ALL_USERS or
    100                                                    KM_TAG_NO_AUTH_REQUIRED is present. */
    101     KM_TAG_NO_AUTH_REQUIRED = KM_BOOL | 503,    /* If key is usable without authentication. */
    102     KM_TAG_USER_AUTH_TYPE = KM_ENUM | 504,      /* Bitmask of authenticator types allowed when
    103                                                  * KM_TAG_USER_SECURE_ID contains a secure user ID,
    104                                                  * rather than a secure authenticator ID.  Defined in
    105                                                  * hw_authenticator_type_t in hw_auth_token.h. */
    106     KM_TAG_AUTH_TIMEOUT = KM_UINT | 505,        /* Required freshness of user authentication for
    107                                                    private/secret key operations, in seconds.
    108                                                    Public key operations require no authentication.
    109                                                    If absent, authentication is required for every
    110                                                    use.  Authentication state is lost when the
    111                                                    device is powered off. */
    112     KM_TAG_ALLOW_WHILE_ON_BODY = KM_BOOL | 506, /* Allow key to be used after authentication timeout
    113                                                  * if device is still on-body (requires secure
    114                                                  * on-body sensor. */
    115     KM_TAG_UNLOCKED_DEVICE_REQUIRED = KM_BOOL | 508, /* Require the device screen to be unlocked if the
    116                                                       * key is used. */
    117 
    118     /* Application access control */
    119     KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* Specified to indicate key is usable by all
    120                                               * applications. */
    121     KM_TAG_APPLICATION_ID = KM_BYTES | 601,  /* Byte string identifying the authorized
    122                                               * application. */
    123     KM_TAG_EXPORTABLE = KM_BOOL | 602,       /* If true, private/secret key can be exported, but
    124                                               * only if all access control requirements for use are
    125                                               * met. (keymaster2) */
    126 
    127     /*
    128      * Semantically unenforceable tags, either because they have no specific meaning or because
    129      * they're informational only.
    130      */
    131     KM_TAG_APPLICATION_DATA = KM_BYTES | 700,      /* Data provided by authorized application. */
    132     KM_TAG_CREATION_DATETIME = KM_DATE | 701,      /* Key creation time */
    133     KM_TAG_ORIGIN = KM_ENUM | 702,                 /* keymaster_key_origin_t. */
    134     KM_TAG_ROLLBACK_RESISTANT = KM_BOOL | 703,     /* Whether key is rollback-resistant. */
    135     KM_TAG_ROOT_OF_TRUST = KM_BYTES | 704,         /* Root of trust ID. */
    136     KM_TAG_OS_VERSION = KM_UINT | 705,             /* Version of system (keymaster2) */
    137     KM_TAG_OS_PATCHLEVEL = KM_UINT | 706,          /* Patch level of system (keymaster2) */
    138     KM_TAG_UNIQUE_ID = KM_BYTES | 707,             /* Used to provide unique ID in attestation */
    139     KM_TAG_ATTESTATION_CHALLENGE = KM_BYTES | 708, /* Used to provide challenge in attestation */
    140     KM_TAG_ATTESTATION_APPLICATION_ID = KM_BYTES | 709, /* Used to identify the set of possible
    141                                                          * applications of which one has initiated
    142                                                          * a key attestation */
    143     KM_TAG_ATTESTATION_ID_BRAND = KM_BYTES | 710,  /* Used to provide the device's brand name to be
    144                                                       included in attestation */
    145     KM_TAG_ATTESTATION_ID_DEVICE = KM_BYTES | 711, /* Used to provide the device's device name to be
    146                                                       included in attestation */
    147     KM_TAG_ATTESTATION_ID_PRODUCT = KM_BYTES | 712, /* Used to provide the device's product name to
    148                                                        be included in attestation */
    149     KM_TAG_ATTESTATION_ID_SERIAL = KM_BYTES | 713, /* Used to provide the device's serial number to
    150                                                       be included in attestation */
    151     KM_TAG_ATTESTATION_ID_IMEI = KM_BYTES | 714,   /* Used to provide the device's IMEI to be
    152                                                       included in attestation */
    153     KM_TAG_ATTESTATION_ID_MEID = KM_BYTES | 715,   /* Used to provide the device's MEID to be
    154                                                       included in attestation */
    155     KM_TAG_ATTESTATION_ID_MANUFACTURER = KM_BYTES | 716, /* Used to provide the device's
    156                                                             manufacturer name to be included in
    157                                                             attestation */
    158     KM_TAG_ATTESTATION_ID_MODEL = KM_BYTES | 717,  /* Used to provide the device's model name to be
    159                                                       included in attestation */
    160 
    161     /* Tags used only to provide data to or receive data from operations */
    162     KM_TAG_ASSOCIATED_DATA = KM_BYTES | 1000, /* Used to provide associated data for AEAD modes. */
    163     KM_TAG_NONCE = KM_BYTES | 1001,           /* Nonce or Initialization Vector */
    164     KM_TAG_AUTH_TOKEN = KM_BYTES | 1002,      /* Authentication token that proves secure user
    165                                                  authentication has been performed.  Structure
    166                                                  defined in hw_auth_token_t in hw_auth_token.h. */
    167     KM_TAG_MAC_LENGTH = KM_UINT | 1003,       /* MAC or AEAD authentication tag length in
    168                                                * bits. */
    169 
    170     KM_TAG_RESET_SINCE_ID_ROTATION = KM_BOOL | 1004, /* Whether the device has beeen factory reset
    171                                                         since the last unique ID rotation.  Used for
    172                                                         key attestation. */
    173 } keymaster_tag_t;
    174 
    175 /**
    176  * Algorithms that may be provided by keymaster implementations.  Those that must be provided by all
    177  * implementations are tagged as "required".
    178  */
    179 typedef enum {
    180     /* Asymmetric algorithms. */
    181     KM_ALGORITHM_RSA = 1,
    182     // KM_ALGORITHM_DSA = 2, -- Removed, do not re-use value 2.
    183     KM_ALGORITHM_EC = 3,
    184 
    185     /* Block ciphers algorithms */
    186     KM_ALGORITHM_AES = 32,
    187     KM_ALGORITHM_TRIPLE_DES = 33,
    188 
    189     /* MAC algorithms */
    190     KM_ALGORITHM_HMAC = 128,
    191 } keymaster_algorithm_t;
    192 
    193 /**
    194  * Symmetric block cipher modes provided by keymaster implementations.
    195  */
    196 typedef enum {
    197     /* Unauthenticated modes, usable only for encryption/decryption and not generally recommended
    198      * except for compatibility with existing other protocols. */
    199     KM_MODE_ECB = 1,
    200     KM_MODE_CBC = 2,
    201     KM_MODE_CTR = 3,
    202 
    203     /* Authenticated modes, usable for encryption/decryption and signing/verification.  Recommended
    204      * over unauthenticated modes for all purposes. */
    205     KM_MODE_GCM = 32,
    206 } keymaster_block_mode_t;
    207 
    208 /**
    209  * Padding modes that may be applied to plaintext for encryption operations.  This list includes
    210  * padding modes for both symmetric and asymmetric algorithms.  Note that implementations should not
    211  * provide all possible combinations of algorithm and padding, only the
    212  * cryptographically-appropriate pairs.
    213  */
    214 typedef enum {
    215     KM_PAD_NONE = 1, /* deprecated */
    216     KM_PAD_RSA_OAEP = 2,
    217     KM_PAD_RSA_PSS = 3,
    218     KM_PAD_RSA_PKCS1_1_5_ENCRYPT = 4,
    219     KM_PAD_RSA_PKCS1_1_5_SIGN = 5,
    220     KM_PAD_PKCS7 = 64,
    221 } keymaster_padding_t;
    222 
    223 /**
    224  * Digests provided by keymaster implementations.
    225  */
    226 typedef enum {
    227     KM_DIGEST_NONE = 0,
    228     KM_DIGEST_MD5 = 1, /* Optional, may not be implemented in hardware, will be handled in software
    229                         * if needed. */
    230     KM_DIGEST_SHA1 = 2,
    231     KM_DIGEST_SHA_2_224 = 3,
    232     KM_DIGEST_SHA_2_256 = 4,
    233     KM_DIGEST_SHA_2_384 = 5,
    234     KM_DIGEST_SHA_2_512 = 6,
    235 } keymaster_digest_t;
    236 
    237 /*
    238  * Key derivation functions, mostly used in ECIES.
    239  */
    240 typedef enum {
    241     /* Do not apply a key derivation function; use the raw agreed key */
    242     KM_KDF_NONE = 0,
    243     /* HKDF defined in RFC 5869 with SHA256 */
    244     KM_KDF_RFC5869_SHA256 = 1,
    245     /* KDF1 defined in ISO 18033-2 with SHA1 */
    246     KM_KDF_ISO18033_2_KDF1_SHA1 = 2,
    247     /* KDF1 defined in ISO 18033-2 with SHA256 */
    248     KM_KDF_ISO18033_2_KDF1_SHA256 = 3,
    249     /* KDF2 defined in ISO 18033-2 with SHA1 */
    250     KM_KDF_ISO18033_2_KDF2_SHA1 = 4,
    251     /* KDF2 defined in ISO 18033-2 with SHA256 */
    252     KM_KDF_ISO18033_2_KDF2_SHA256 = 5,
    253 } keymaster_kdf_t;
    254 
    255 /**
    256  * Supported EC curves, used in ECDSA/ECIES.
    257  */
    258 typedef enum {
    259     KM_EC_CURVE_P_224 = 0,
    260     KM_EC_CURVE_P_256 = 1,
    261     KM_EC_CURVE_P_384 = 2,
    262     KM_EC_CURVE_P_521 = 3,
    263 } keymaster_ec_curve_t;
    264 
    265 /**
    266  * The origin of a key (or pair), i.e. where it was generated.  Note that KM_TAG_ORIGIN can be found
    267  * in either the hardware-enforced or software-enforced list for a key, indicating whether the key
    268  * is hardware or software-based.  Specifically, a key with KM_ORIGIN_GENERATED in the
    269  * hardware-enforced list is guaranteed never to have existed outide the secure hardware.
    270  */
    271 typedef enum {
    272     KM_ORIGIN_GENERATED = 0, /* Generated in keymaster.  Should not exist outside the TEE. */
    273     KM_ORIGIN_DERIVED = 1,   /* Derived inside keymaster.  Likely exists off-device. */
    274     KM_ORIGIN_IMPORTED = 2,  /* Imported into keymaster.  Existed as cleartext in Android. */
    275     KM_ORIGIN_UNKNOWN = 3,   /* Keymaster did not record origin.  This value can only be seen on
    276                               * keys in a keymaster0 implementation.  The keymaster0 adapter uses
    277                               * this value to document the fact that it is unkown whether the key
    278                               * was generated inside or imported into keymaster. */
    279 } keymaster_key_origin_t;
    280 
    281 /**
    282  * Usability requirements of key blobs.  This defines what system functionality must be available
    283  * for the key to function.  For example, key "blobs" which are actually handles referencing
    284  * encrypted key material stored in the file system cannot be used until the file system is
    285  * available, and should have BLOB_REQUIRES_FILE_SYSTEM.  Other requirements entries will be added
    286  * as needed for implementations.
    287  */
    288 typedef enum {
    289     KM_BLOB_STANDALONE = 0,
    290     KM_BLOB_REQUIRES_FILE_SYSTEM = 1,
    291 } keymaster_key_blob_usage_requirements_t;
    292 
    293 /**
    294  * Possible purposes of a key (or pair).
    295  */
    296 typedef enum {
    297     KM_PURPOSE_ENCRYPT = 0,    /* Usable with RSA, EC and AES keys. */
    298     KM_PURPOSE_DECRYPT = 1,    /* Usable with RSA, EC and AES keys. */
    299     KM_PURPOSE_SIGN = 2,       /* Usable with RSA, EC and HMAC keys. */
    300     KM_PURPOSE_VERIFY = 3,     /* Usable with RSA, EC and HMAC keys. */
    301     KM_PURPOSE_DERIVE_KEY = 4, /* Usable with EC keys. */
    302     KM_PURPOSE_WRAP = 5,       /* Usable with wrapped keys. */
    303 
    304 } keymaster_purpose_t;
    305 
    306 typedef struct {
    307     const uint8_t* data;
    308     size_t data_length;
    309 } keymaster_blob_t;
    310 
    311 typedef struct {
    312     keymaster_tag_t tag;
    313     union {
    314         uint32_t enumerated;   /* KM_ENUM and KM_ENUM_REP */
    315         bool boolean;          /* KM_BOOL */
    316         uint32_t integer;      /* KM_INT and KM_INT_REP */
    317         uint64_t long_integer; /* KM_LONG */
    318         uint64_t date_time;    /* KM_DATE */
    319         keymaster_blob_t blob; /* KM_BIGNUM and KM_BYTES*/
    320     };
    321 } keymaster_key_param_t;
    322 
    323 typedef struct {
    324     keymaster_key_param_t* params; /* may be NULL if length == 0 */
    325     size_t length;
    326 } keymaster_key_param_set_t;
    327 
    328 /**
    329  * Parameters that define a key's characteristics, including authorized modes of usage and access
    330  * control restrictions.  The parameters are divided into two categories, those that are enforced by
    331  * secure hardware, and those that are not.  For a software-only keymaster implementation the
    332  * enforced array must NULL.  Hardware implementations must enforce everything in the enforced
    333  * array.
    334  */
    335 typedef struct {
    336     keymaster_key_param_set_t hw_enforced;
    337     keymaster_key_param_set_t sw_enforced;
    338 } keymaster_key_characteristics_t;
    339 
    340 typedef struct {
    341     const uint8_t* key_material;
    342     size_t key_material_size;
    343 } keymaster_key_blob_t;
    344 
    345 typedef struct {
    346     keymaster_blob_t* entries;
    347     size_t entry_count;
    348 } keymaster_cert_chain_t;
    349 
    350 typedef enum {
    351     KM_VERIFIED_BOOT_VERIFIED = 0,    /* Full chain of trust extending from the bootloader to
    352                                        * verified partitions, including the bootloader, boot
    353                                        * partition, and all verified partitions*/
    354     KM_VERIFIED_BOOT_SELF_SIGNED = 1, /* The boot partition has been verified using the embedded
    355                                        * certificate, and the signature is valid. The bootloader
    356                                        * displays a warning and the fingerprint of the public
    357                                        * key before allowing the boot process to continue.*/
    358     KM_VERIFIED_BOOT_UNVERIFIED = 2,  /* The device may be freely modified. Device integrity is left
    359                                        * to the user to verify out-of-band. The bootloader
    360                                        * displays a warning to the user before allowing the boot
    361                                        * process to continue */
    362     KM_VERIFIED_BOOT_FAILED = 3,      /* The device failed verification. The bootloader displays a
    363                                        * warning and stops the boot process, so no keymaster
    364                                        * implementation should ever actually return this value,
    365                                        * since it should not run.  Included here only for
    366                                        * completeness. */
    367 } keymaster_verified_boot_t;
    368 
    369 typedef enum {
    370     KM_SECURITY_LEVEL_SOFTWARE = 0,
    371     KM_SECURITY_LEVEL_TRUSTED_ENVIRONMENT = 1,
    372 } keymaster_security_level_t;
    373 
    374 /**
    375  * Formats for key import and export.
    376  */
    377 typedef enum {
    378     KM_KEY_FORMAT_X509 = 0,  /* for public key export */
    379     KM_KEY_FORMAT_PKCS8 = 1, /* for asymmetric key pair import */
    380     KM_KEY_FORMAT_RAW = 3,   /* for symmetric key import and export*/
    381 } keymaster_key_format_t;
    382 
    383 /**
    384  * The keymaster operation API consists of begin, update, finish and abort. This is the type of the
    385  * handle used to tie the sequence of calls together.  A 64-bit value is used because it's important
    386  * that handles not be predictable.  Implementations must use strong random numbers for handle
    387  * values.
    388  */
    389 typedef uint64_t keymaster_operation_handle_t;
    390 
    391 typedef enum {
    392     KM_ERROR_OK = 0,
    393     KM_ERROR_ROOT_OF_TRUST_ALREADY_SET = -1,
    394     KM_ERROR_UNSUPPORTED_PURPOSE = -2,
    395     KM_ERROR_INCOMPATIBLE_PURPOSE = -3,
    396     KM_ERROR_UNSUPPORTED_ALGORITHM = -4,
    397     KM_ERROR_INCOMPATIBLE_ALGORITHM = -5,
    398     KM_ERROR_UNSUPPORTED_KEY_SIZE = -6,
    399     KM_ERROR_UNSUPPORTED_BLOCK_MODE = -7,
    400     KM_ERROR_INCOMPATIBLE_BLOCK_MODE = -8,
    401     KM_ERROR_UNSUPPORTED_MAC_LENGTH = -9,
    402     KM_ERROR_UNSUPPORTED_PADDING_MODE = -10,
    403     KM_ERROR_INCOMPATIBLE_PADDING_MODE = -11,
    404     KM_ERROR_UNSUPPORTED_DIGEST = -12,
    405     KM_ERROR_INCOMPATIBLE_DIGEST = -13,
    406     KM_ERROR_INVALID_EXPIRATION_TIME = -14,
    407     KM_ERROR_INVALID_USER_ID = -15,
    408     KM_ERROR_INVALID_AUTHORIZATION_TIMEOUT = -16,
    409     KM_ERROR_UNSUPPORTED_KEY_FORMAT = -17,
    410     KM_ERROR_INCOMPATIBLE_KEY_FORMAT = -18,
    411     KM_ERROR_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM = -19,   /* For PKCS8 & PKCS12 */
    412     KM_ERROR_UNSUPPORTED_KEY_VERIFICATION_ALGORITHM = -20, /* For PKCS8 & PKCS12 */
    413     KM_ERROR_INVALID_INPUT_LENGTH = -21,
    414     KM_ERROR_KEY_EXPORT_OPTIONS_INVALID = -22,
    415     KM_ERROR_DELEGATION_NOT_ALLOWED = -23,
    416     KM_ERROR_KEY_NOT_YET_VALID = -24,
    417     KM_ERROR_KEY_EXPIRED = -25,
    418     KM_ERROR_KEY_USER_NOT_AUTHENTICATED = -26,
    419     KM_ERROR_OUTPUT_PARAMETER_NULL = -27,
    420     KM_ERROR_INVALID_OPERATION_HANDLE = -28,
    421     KM_ERROR_INSUFFICIENT_BUFFER_SPACE = -29,
    422     KM_ERROR_VERIFICATION_FAILED = -30,
    423     KM_ERROR_TOO_MANY_OPERATIONS = -31,
    424     KM_ERROR_UNEXPECTED_NULL_POINTER = -32,
    425     KM_ERROR_INVALID_KEY_BLOB = -33,
    426     KM_ERROR_IMPORTED_KEY_NOT_ENCRYPTED = -34,
    427     KM_ERROR_IMPORTED_KEY_DECRYPTION_FAILED = -35,
    428     KM_ERROR_IMPORTED_KEY_NOT_SIGNED = -36,
    429     KM_ERROR_IMPORTED_KEY_VERIFICATION_FAILED = -37,
    430     KM_ERROR_INVALID_ARGUMENT = -38,
    431     KM_ERROR_UNSUPPORTED_TAG = -39,
    432     KM_ERROR_INVALID_TAG = -40,
    433     KM_ERROR_MEMORY_ALLOCATION_FAILED = -41,
    434     KM_ERROR_IMPORT_PARAMETER_MISMATCH = -44,
    435     KM_ERROR_SECURE_HW_ACCESS_DENIED = -45,
    436     KM_ERROR_OPERATION_CANCELLED = -46,
    437     KM_ERROR_CONCURRENT_ACCESS_CONFLICT = -47,
    438     KM_ERROR_SECURE_HW_BUSY = -48,
    439     KM_ERROR_SECURE_HW_COMMUNICATION_FAILED = -49,
    440     KM_ERROR_UNSUPPORTED_EC_FIELD = -50,
    441     KM_ERROR_MISSING_NONCE = -51,
    442     KM_ERROR_INVALID_NONCE = -52,
    443     KM_ERROR_MISSING_MAC_LENGTH = -53,
    444     KM_ERROR_KEY_RATE_LIMIT_EXCEEDED = -54,
    445     KM_ERROR_CALLER_NONCE_PROHIBITED = -55,
    446     KM_ERROR_KEY_MAX_OPS_EXCEEDED = -56,
    447     KM_ERROR_INVALID_MAC_LENGTH = -57,
    448     KM_ERROR_MISSING_MIN_MAC_LENGTH = -58,
    449     KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH = -59,
    450     KM_ERROR_UNSUPPORTED_KDF = -60,
    451     KM_ERROR_UNSUPPORTED_EC_CURVE = -61,
    452     KM_ERROR_KEY_REQUIRES_UPGRADE = -62,
    453     KM_ERROR_ATTESTATION_CHALLENGE_MISSING = -63,
    454     KM_ERROR_KEYMASTER_NOT_CONFIGURED = -64,
    455     KM_ERROR_ATTESTATION_APPLICATION_ID_MISSING = -65,
    456     KM_ERROR_CANNOT_ATTEST_IDS = -66,
    457     KM_ERROR_DEVICE_LOCKED = -72,
    458 
    459     KM_ERROR_UNIMPLEMENTED = -100,
    460     KM_ERROR_VERSION_MISMATCH = -101,
    461 
    462     KM_ERROR_UNKNOWN_ERROR = -1000,
    463 } keymaster_error_t;
    464 
    465 /* Convenience functions for manipulating keymaster tag types */
    466 
    467 static inline keymaster_tag_type_t keymaster_tag_get_type(keymaster_tag_t tag) {
    468     return (keymaster_tag_type_t)(tag & (0xF << 28));
    469 }
    470 
    471 static inline uint32_t keymaster_tag_mask_type(keymaster_tag_t tag) {
    472     return tag & 0x0FFFFFFF;
    473 }
    474 
    475 static inline bool keymaster_tag_type_repeatable(keymaster_tag_type_t type) {
    476     switch (type) {
    477     case KM_UINT_REP:
    478     case KM_ENUM_REP:
    479         return true;
    480     default:
    481         return false;
    482     }
    483 }
    484 
    485 static inline bool keymaster_tag_repeatable(keymaster_tag_t tag) {
    486     return keymaster_tag_type_repeatable(keymaster_tag_get_type(tag));
    487 }
    488 
    489 /* Convenience functions for manipulating keymaster_key_param_t structs */
    490 
    491 inline keymaster_key_param_t keymaster_param_enum(keymaster_tag_t tag, uint32_t value) {
    492     // assert(keymaster_tag_get_type(tag) == KM_ENUM || keymaster_tag_get_type(tag) == KM_ENUM_REP);
    493     keymaster_key_param_t param;
    494     memset(&param, 0, sizeof(param));
    495     param.tag = tag;
    496     param.enumerated = value;
    497     return param;
    498 }
    499 
    500 inline keymaster_key_param_t keymaster_param_int(keymaster_tag_t tag, uint32_t value) {
    501     // assert(keymaster_tag_get_type(tag) == KM_INT || keymaster_tag_get_type(tag) == KM_INT_REP);
    502     keymaster_key_param_t param;
    503     memset(&param, 0, sizeof(param));
    504     param.tag = tag;
    505     param.integer = value;
    506     return param;
    507 }
    508 
    509 inline keymaster_key_param_t keymaster_param_long(keymaster_tag_t tag, uint64_t value) {
    510     // assert(keymaster_tag_get_type(tag) == KM_LONG);
    511     keymaster_key_param_t param;
    512     memset(&param, 0, sizeof(param));
    513     param.tag = tag;
    514     param.long_integer = value;
    515     return param;
    516 }
    517 
    518 inline keymaster_key_param_t keymaster_param_blob(keymaster_tag_t tag, const uint8_t* bytes,
    519                                                   size_t bytes_len) {
    520     // assert(keymaster_tag_get_type(tag) == KM_BYTES || keymaster_tag_get_type(tag) == KM_BIGNUM);
    521     keymaster_key_param_t param;
    522     memset(&param, 0, sizeof(param));
    523     param.tag = tag;
    524     param.blob.data = (uint8_t*)bytes;
    525     param.blob.data_length = bytes_len;
    526     return param;
    527 }
    528 
    529 inline keymaster_key_param_t keymaster_param_bool(keymaster_tag_t tag) {
    530     // assert(keymaster_tag_get_type(tag) == KM_BOOL);
    531     keymaster_key_param_t param;
    532     memset(&param, 0, sizeof(param));
    533     param.tag = tag;
    534     param.boolean = true;
    535     return param;
    536 }
    537 
    538 inline keymaster_key_param_t keymaster_param_date(keymaster_tag_t tag, uint64_t value) {
    539     // assert(keymaster_tag_get_type(tag) == KM_DATE);
    540     keymaster_key_param_t param;
    541     memset(&param, 0, sizeof(param));
    542     param.tag = tag;
    543     param.date_time = value;
    544     return param;
    545 }
    546 
    547 #define KEYMASTER_SIMPLE_COMPARE(a, b) (a < b) ? -1 : ((a > b) ? 1 : 0)
    548 inline int keymaster_param_compare(const keymaster_key_param_t* a, const keymaster_key_param_t* b) {
    549     int retval = KEYMASTER_SIMPLE_COMPARE((uint32_t)a->tag, (uint32_t)b->tag);
    550     if (retval != 0)
    551         return retval;
    552 
    553     switch (keymaster_tag_get_type(a->tag)) {
    554     case KM_INVALID:
    555     case KM_BOOL:
    556         return 0;
    557     case KM_ENUM:
    558     case KM_ENUM_REP:
    559         return KEYMASTER_SIMPLE_COMPARE(a->enumerated, b->enumerated);
    560     case KM_UINT:
    561     case KM_UINT_REP:
    562         return KEYMASTER_SIMPLE_COMPARE(a->integer, b->integer);
    563     case KM_ULONG:
    564     case KM_ULONG_REP:
    565         return KEYMASTER_SIMPLE_COMPARE(a->long_integer, b->long_integer);
    566     case KM_DATE:
    567         return KEYMASTER_SIMPLE_COMPARE(a->date_time, b->date_time);
    568     case KM_BIGNUM:
    569     case KM_BYTES:
    570         // Handle the empty cases.
    571         if (a->blob.data_length != 0 && b->blob.data_length == 0)
    572             return -1;
    573         if (a->blob.data_length == 0 && b->blob.data_length == 0)
    574             return 0;
    575         if (a->blob.data_length == 0 && b->blob.data_length > 0)
    576             return 1;
    577 
    578         retval = memcmp(a->blob.data, b->blob.data, a->blob.data_length < b->blob.data_length
    579                                                         ? a->blob.data_length
    580                                                         : b->blob.data_length);
    581         if (retval != 0)
    582             return retval;
    583         else if (a->blob.data_length != b->blob.data_length) {
    584             // Equal up to the common length; longer one is larger.
    585             if (a->blob.data_length < b->blob.data_length)
    586                 return -1;
    587             if (a->blob.data_length > b->blob.data_length)
    588                 return 1;
    589         };
    590     }
    591 
    592     return 0;
    593 }
    594 #undef KEYMASTER_SIMPLE_COMPARE
    595 
    596 inline void keymaster_free_param_values(keymaster_key_param_t* param, size_t param_count) {
    597     while (param_count > 0) {
    598         param_count--;
    599         switch (keymaster_tag_get_type(param->tag)) {
    600         case KM_BIGNUM:
    601         case KM_BYTES:
    602             free((void*)param->blob.data);
    603             param->blob.data = NULL;
    604             break;
    605         default:
    606             // NOP
    607             break;
    608         }
    609         ++param;
    610     }
    611 }
    612 
    613 inline void keymaster_free_param_set(keymaster_key_param_set_t* set) {
    614     if (set) {
    615         keymaster_free_param_values(set->params, set->length);
    616         free(set->params);
    617         set->params = NULL;
    618         set->length = 0;
    619     }
    620 }
    621 
    622 inline void keymaster_free_characteristics(keymaster_key_characteristics_t* characteristics) {
    623     if (characteristics) {
    624         keymaster_free_param_set(&characteristics->hw_enforced);
    625         keymaster_free_param_set(&characteristics->sw_enforced);
    626     }
    627 }
    628 
    629 inline void keymaster_free_cert_chain(keymaster_cert_chain_t* chain) {
    630     if (chain) {
    631         for (size_t i = 0; i < chain->entry_count; ++i) {
    632             free((uint8_t*)chain->entries[i].data);
    633             chain->entries[i].data = NULL;
    634             chain->entries[i].data_length = 0;
    635         }
    636         free(chain->entries);
    637         chain->entries = NULL;
    638         chain->entry_count = 0;
    639     }
    640 }
    641 
    642 #ifdef __cplusplus
    643 }  // extern "C"
    644 #endif  // __cplusplus
    645 
    646 #endif  // ANDROID_HARDWARE_KEYMASTER_DEFS_H
    647