Add keymaster2 HAL.

Change-Id: Ibfcda30f33077f61e74701fa026983f9e72e140e
This commit is contained in:
Shawn Willden 2015-12-21 16:29:10 -07:00
parent 87882cc0f2
commit cf30fe17fd
3 changed files with 527 additions and 31 deletions

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@ -0,0 +1,452 @@
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_HARDWARE_KEYMASTER2_H
#define ANDROID_HARDWARE_KEYMASTER2_H
#include <hardware/keymaster_common.h>
#include <hardware/keymaster_defs.h>
__BEGIN_DECLS
/**
* Keymaster2 device definition
*/
struct keymaster2_device {
/**
* Common methods of the keymaster device. This *must* be the first member of
* keymaster_device as users of this structure will cast a hw_device_t to
* keymaster_device pointer in contexts where it's known the hw_device_t references a
* keymaster_device.
*/
struct hw_device_t common;
void* context;
/**
* See flags defined for keymaster0_devices::flags in keymaster_common.h. Used only for
* backward compatibility; keymaster2 hardware devices must set this to zero.
*/
uint32_t flags;
/**
* Adds entropy to the RNG used by keymaster. Entropy added through this method is guaranteed
* not to be the only source of entropy used, and the mixing function is required to be secure,
* in the sense that if the RNG is seeded (from any source) with any data the attacker cannot
* predict (or control), then the RNG output is indistinguishable from random. Thus, if the
* entropy from any source is good, the output will be good.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] data Random data to be mixed in.
*
* \param[in] data_length Length of \p data.
*/
keymaster_error_t (*add_rng_entropy)(const struct keymaster2_device* dev, const uint8_t* data,
size_t data_length);
/**
* Generates a key, or key pair, returning a key blob and/or a description of the key.
*
* Key generation parameters are defined as keymaster tag/value pairs, provided in \p params.
* See keymaster_tag_t for the full list. Some values that are always required for generation
* of useful keys are:
*
* - KM_TAG_ALGORITHM;
* - KM_TAG_PURPOSE; and
* - (KM_TAG_USER_SECURE_ID and KM_TAG_USER_AUTH_TYPE) or KM_TAG_NO_AUTH_REQUIRED.
*
* KM_TAG_AUTH_TIMEOUT should generally be specified unless KM_TAG_NO_AUTH_REQUIRED is present,
* or the user will have to authenticate for every use.
*
* KM_TAG_BLOCK_MODE, KM_TAG_PADDING, KM_TAG_MAC_LENGTH and KM_TAG_DIGEST must be specified for
* algorithms that require them.
*
* The following tags may not be specified; their values will be provided by the implementation.
*
* - KM_TAG_ORIGIN,
* - KM_TAG_ROLLBACK_RESISTANT,
* - KM_TAG_CREATION_DATETIME
*
* \param[in] dev The keymaster device structure.
*
* \param[in] params Array of key generation param
*
* \param[out] key_blob returns the generated key. \p key_blob must not be NULL. The caller
* assumes ownership key_blob->key_material and must free() it.
*
* \param[out] characteristics returns the characteristics of the key that was, generated, if
* non-NULL. If non-NULL, the caller assumes ownership and must deallocate with
* keymaster_free_characteristics(). Note that KM_TAG_ROOT_OF_TRUST, KM_TAG_APPLICATION_ID and
* KM_TAG_APPLICATION_DATA are never returned.
*/
keymaster_error_t (*generate_key)(const struct keymaster2_device* dev,
const keymaster_key_param_set_t* params,
keymaster_key_blob_t* key_blob,
keymaster_key_characteristics_t* characteristics);
/**
* Returns the characteristics of the specified key, or KM_ERROR_INVALID_KEY_BLOB if the
* key_blob is invalid (implementations must fully validate the integrity of the key).
* client_id and app_data must be the ID and data provided when the key was generated or
* imported, or empty if KM_TAG_APPLICATION_ID and/or KM_TAG_APPLICATION_DATA were not provided
* during generation. Those values are not included in the returned characteristics. The
* caller assumes ownership of the allocated characteristics object, which must be deallocated
* with keymaster_free_characteristics().
*
* Note that KM_TAG_APPLICATION_ID and KM_TAG_APPLICATION_DATA are never returned.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] key_blob The key to retreive characteristics from.
*
* \param[in] client_id The client ID data, or NULL if none associated.
*
* \param[in] app_id The app data, or NULL if none associated.
*
* \param[out] characteristics The key characteristics. Must not be NULL. The caller assumes
* ownership of the contents and must deallocate with keymaster_free_characteristics().
*/
keymaster_error_t (*get_key_characteristics)(const struct keymaster2_device* dev,
const keymaster_key_blob_t* key_blob,
const keymaster_blob_t* client_id,
const keymaster_blob_t* app_data,
keymaster_key_characteristics_t* characteristics);
/**
* Imports a key, or key pair, returning a key blob and/or a description of the key.
*
* Most key import parameters are defined as keymaster tag/value pairs, provided in "params".
* See keymaster_tag_t for the full list. Values that are always required for import of useful
* keys are:
*
* - KM_TAG_ALGORITHM;
* - KM_TAG_PURPOSE; and
* - (KM_TAG_USER_SECURE_ID and KM_TAG_USER_AUTH_TYPE) or KM_TAG_NO_AUTH_REQUIRED.
*
* KM_TAG_AUTH_TIMEOUT should generally be specified. If unspecified, the user will have to
* authenticate for every use.
*
* The following tags will take default values if unspecified:
*
* - KM_TAG_KEY_SIZE will default to the size of the key provided.
* - KM_TAG_RSA_PUBLIC_EXPONENT will default to the value in the key provided (for RSA keys)
*
* The following tags may not be specified; their values will be provided by the implementation.
*
* - KM_TAG_ORIGIN,
* - KM_TAG_ROLLBACK_RESISTANT,
* - KM_TAG_CREATION_DATETIME
*
* \param[in] dev The keymaster device structure.
*
* \param[in] params Parameters defining the imported key.
*
* \param[in] params_count The number of entries in \p params.
*
* \param[in] key_format specifies the format of the key data in key_data.
*
* \param[out] key_blob Used to return the opaque key blob. Must be non-NULL. The caller
* assumes ownership of the contained key_material.
*
* \param[out] characteristics Used to return the characteristics of the imported key. May be
* NULL, in which case no characteristics will be returned. If non-NULL, the caller assumes
* ownership of the contents and must deallocate with keymaster_free_characteristics(). Note
* that KM_TAG_APPLICATION_ID and KM_TAG_APPLICATION_DATA are never returned.
*/
keymaster_error_t (*import_key)(const struct keymaster2_device* dev,
const keymaster_key_param_set_t* params,
keymaster_key_format_t key_format,
const keymaster_blob_t* key_data,
keymaster_key_blob_t* key_blob,
keymaster_key_characteristics_t* characteristics);
/**
* Exports a public or symmetric key, returning a byte array in the specified format.
*
* Note that symmetric key export is allowed only if the key was created with KM_TAG_EXPORTABLE,
* and only if all of the requirements for key usage (e.g. authentication) are met.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] export_format The format to be used for exporting the key.
*
* \param[in] key_to_export The key to export.
*
* \param[in] client_id Client ID blob, which must match the blob provided in
* KM_TAG_APPLICATION_ID during key generation (if any).
*
* \param[in] app_data Appliation data blob, which must match the blob provided in
* KM_TAG_APPLICATION_DATA during key generation (if any).
*
* \param[out] export_data The exported key material. The caller assumes ownership.
*/
keymaster_error_t (*export_key)(const struct keymaster2_device* dev,
keymaster_key_format_t export_format,
const keymaster_key_blob_t* key_to_export,
const keymaster_blob_t* client_id,
const keymaster_blob_t* app_data,
keymaster_blob_t* export_data);
/**
* Derives a shared secret key from \p key, which must be an EC key, and the public key found in
* /p other_key_certificate, an X.509 certificate containing a compatible EC public key. The
* derived key's characteristics are described in \p new_key_params, which must include
* algorithm (KM_TAG_ALGORITHM), key size (KM_TAG_KEY_SIZE) and KDF (KM_TAG_KDF) as well as
* other desired key characteristics. The resulting key material is not returned directly, but
* instead a new keymaster key is created and the associated blob returned in \p key_blob. If
* \p characteristics is non-NULL, the new key's characteristics are placed there.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] key The keymaster key to use for key agreement. This must be an EC key with the
* KM_PURPOSE_DERIVE_KEY purpose.
*
* \param[in] other_key_certificate An X.509 certificate or certificate fragment containing a
* SubjectPublicKey field containing an EC public key on the same curve as \p key.
*
* \param[in] new_key_params A set of parameters to define/describe the newly-derived symmetric
* key. The parameters will define how the key may be used. The set must include KM_TAG_KDF to
* specify how the raw agreed key bytes will be transformed to produce the key material.
*
* \param[out] key_blob The key blob containing the newly-derived key. The caller takes
* ownership of the returned blob.
*
* \param[out] characteristics. If non-null, will be used to return the characteristics of the
* new key blob, which will have KM_TAG_ORIGIN set to KM_ORIGIN_DERIVED. The caller takes
* ownership of the returned characteristics and must deallocate with
* keymaster_free_characteristics().
*/
keymaster_error_t (*agree_key)(const struct keymaster2_device* dev,
const keymaster_key_blob_t* key,
const keymaster_blob_t* other_key_certificate,
const keymaster_key_param_set_t* new_key_params,
keymaster_key_blob_t* new_key_blob,
keymaster_key_characteristics_t* characteristics);
/**
* Generates a signed X.509 certificate chain attesting to the presence of \p key_to_attest in
* keymaster (TODO(swillden): Describe certificate contents in more detail). The certificate
* will contain an extension with OID 1.3.6.1.4.1.11129.2.1.17 and value defined in
* <TODO:swillden -- insert link here> which contains the key description.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] key_to_attest The keymaster key for which the attestation certificate will be
* generated.
*
* \param[in] attest_params Parameters defining how to do the attestation. At present the only
* parameter is KM_TAG_ALGORITHM, which must be either KM_ALGORITHM_EC or KM_ALGORITHM_RSA.
* This selects which of the provisioned attestation keys will be used to sign the certificate.
*
* \param[out] cert_chain An array of DER-encoded X.509 certificates. The first will be the
* certificate for \p key_to_attest. The remaining entries will chain back to the root. The
* caller takes ownership and must deallocate with keymaster_free_cert_chain.
*/
keymaster_error_t (*attest_key)(const struct keymaster2_device* dev,
const keymaster_key_blob_t* key_to_attest,
const keymaster_key_param_set_t* attest_params,
keymaster_cert_chain_t* cert_chain);
/**
* Upgrades an old key. Keys can become "old" in two ways: Keymaster can be upgraded to a new
* version, or the system can be updated to invalidate the OS version and/or patch level. In
* either case, attempts to use an old key will result in keymaster returning
* KM_ERROR_KEY_REQUIRES_UPGRADE. This method should then be called to upgrade the key.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] key_to_upgrade The keymaster key to upgrade.
*
* \param[in] upgrade_params Parameters needed to complete the upgrade. In particular,
* KM_TAG_APPLICATION_ID and KM_TAG_APPLICATION_DATA will be required if they were defined for
* the key.
*
* \param[out] upgraded_key The upgraded key blob.
*/
keymaster_error_t (*upgrade_key)(const struct keymaster2_device* dev,
const keymaster_key_blob_t* key_to_upgrade,
const keymaster_key_param_set_t* upgrade_params,
keymaster_key_blob_t* upgraded_key);
/**
* Deletes the key, or key pair, associated with the key blob. After calling this function it
* will be impossible to use the key for any other operations. May be applied to keys from
* foreign roots of trust (keys not usable under the current root of trust).
*
* This function is optional and should be set to NULL if it is not implemented.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] key The key to be deleted.
*/
keymaster_error_t (*delete_key)(const struct keymaster2_device* dev,
const keymaster_key_blob_t* key);
/**
* Deletes all keys in the hardware keystore. Used when keystore is reset completely. After
* calling this function it will be impossible to use any previously generated or imported key
* blobs for any operations.
*
* This function is optional and should be set to NULL if it is not implemented.
*
* \param[in] dev The keymaster device structure.
*/
keymaster_error_t (*delete_all_keys)(const struct keymaster2_device* dev);
/**
* Begins a cryptographic operation using the specified key. If all is well, begin() will
* return KM_ERROR_OK and create an operation handle which must be passed to subsequent calls to
* update(), finish() or abort().
*
* It is critical that each call to begin() be paired with a subsequent call to finish() or
* abort(), to allow the keymaster implementation to clean up any internal operation state.
* Failure to do this may leak internal state space or other internal resources and may
* eventually cause begin() to return KM_ERROR_TOO_MANY_OPERATIONS when it runs out of space for
* operations. Any result other than KM_ERROR_OK from begin(), update() or finish() implicitly
* aborts the operation, in which case abort() need not be called (and will return
* KM_ERROR_INVALID_OPERATION_HANDLE if called).
*
* \param[in] dev The keymaster device structure.
*
* \param[in] purpose The purpose of the operation, one of KM_PURPOSE_ENCRYPT,
* KM_PURPOSE_DECRYPT, KM_PURPOSE_SIGN or KM_PURPOSE_VERIFY. Note that for AEAD modes,
* encryption and decryption imply signing and verification, respectively, but should be
* specified as KM_PURPOSE_ENCRYPT and KM_PURPOSE_DECRYPT.
*
* \param[in] key The key to be used for the operation. \p key must have a purpose compatible
* with \p purpose and all of its usage requirements must be satisfied, or begin() will return
* an appropriate error code.
*
* \param[in] in_params Additional parameters for the operation. This is typically used to
* provide authentication data, with KM_TAG_AUTH_TOKEN. If KM_TAG_APPLICATION_ID or
* KM_TAG_APPLICATION_DATA were provided during generation, they must be provided here, or the
* operation will fail with KM_ERROR_INVALID_KEY_BLOB. For operations that require a nonce or
* IV, on keys that were generated with KM_TAG_CALLER_NONCE, in_params may contain a tag
* KM_TAG_NONCE.
*
* \param[out] out_params Output parameters. Used to return additional data from the operation
* initialization, notably to return the IV or nonce from operations that generate an IV or
* nonce. The caller takes ownership of the output parameters array and must free it with
* keymaster_free_param_set(). out_params may be set to NULL if no output parameters are
* expected. If out_params is NULL, and output paramaters are generated, begin() will return
* KM_ERROR_OUTPUT_PARAMETER_NULL.
*
* \param[out] operation_handle The newly-created operation handle which must be passed to
* update(), finish() or abort(). If operation_handle is NULL, begin() will return
* KM_ERROR_OUTPUT_PARAMETER_NULL.
*/
keymaster_error_t (*begin)(const struct keymaster2_device* dev, keymaster_purpose_t purpose,
const keymaster_key_blob_t* key,
const keymaster_key_param_set_t* in_params,
keymaster_key_param_set_t* out_params,
keymaster_operation_handle_t* operation_handle);
/**
* Provides data to, and possibly receives output from, an ongoing cryptographic operation begun
* with begin().
*
* If operation_handle is invalid, update() will return KM_ERROR_INVALID_OPERATION_HANDLE.
*
* update() may not consume all of the data provided in the data buffer. update() will return
* the amount consumed in *data_consumed. The caller should provide the unconsumed data in a
* subsequent call.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] operation_handle The operation handle returned by begin().
*
* \param[in] in_params Additional parameters for the operation. For AEAD modes, this is used
* to specify KM_TAG_ADDITIONAL_DATA. Note that additional data may be provided in multiple
* calls to update(), but only until input data has been provided.
*
* \param[in] input Data to be processed, per the parameters established in the call to begin().
* Note that update() may or may not consume all of the data provided. See \p input_consumed.
*
* \param[out] input_consumed Amount of data that was consumed by update(). If this is less
* than the amount provided, the caller should provide the remainder in a subsequent call to
* update().
*
* \param[out] out_params Output parameters. Used to return additional data from the operation
* The caller takes ownership of the output parameters array and must free it with
* keymaster_free_param_set(). out_params may be set to NULL if no output parameters are
* expected. If out_params is NULL, and output paramaters are generated, begin() will return
* KM_ERROR_OUTPUT_PARAMETER_NULL.
*
* \param[out] output The output data, if any. The caller assumes ownership of the allocated
* buffer. output must not be NULL.
*
* Note that update() may not provide any output, in which case output->data_length will be
* zero, and output->data may be either NULL or zero-length (so the caller should always free()
* it).
*/
keymaster_error_t (*update)(const struct keymaster2_device* dev,
keymaster_operation_handle_t operation_handle,
const keymaster_key_param_set_t* in_params,
const keymaster_blob_t* input, size_t* input_consumed,
keymaster_key_param_set_t* out_params, keymaster_blob_t* output);
/**
* Finalizes a cryptographic operation begun with begin() and invalidates \p operation_handle.
*
* \param[in] dev The keymaster device structure.
*
* \param[in] operation_handle The operation handle returned by begin(). This handle will be
* invalidated.
*
* \param[in] in_params Additional parameters for the operation. For AEAD modes, this is used
* to specify KM_TAG_ADDITIONAL_DATA, but only if no input data was provided to update().
*
* \param[in] input Data to be processed, per the parameters established in the call to
* begin(). finish() must consume all provided data or return KM_ERROR_INVALID_INPUT_LENGTH.
*
* \param[in] signature The signature to be verified if the purpose specified in the begin()
* call was KM_PURPOSE_VERIFY.
*
* \param[out] output The output data, if any. The caller assumes ownership of the allocated
* buffer.
*
* If the operation being finished is a signature verification or an AEAD-mode decryption and
* verification fails then finish() will return KM_ERROR_VERIFICATION_FAILED.
*/
keymaster_error_t (*finish)(const struct keymaster2_device* dev,
keymaster_operation_handle_t operation_handle,
const keymaster_key_param_set_t* in_params,
const keymaster_blob_t* input, const keymaster_blob_t* signature,
keymaster_key_param_set_t* out_params, keymaster_blob_t* output);
/**
* Aborts a cryptographic operation begun with begin(), freeing all internal resources and
* invalidating \p operation_handle.
*/
keymaster_error_t (*abort)(const struct keymaster2_device* dev,
keymaster_operation_handle_t operation_handle);
};
typedef struct keymaster2_device keymaster2_device_t;
/* Convenience API for opening and closing keymaster devices */
static inline int keymaster2_open(const struct hw_module_t* module, keymaster2_device_t** device) {
return module->methods->open(module, KEYSTORE_KEYMASTER, (struct hw_device_t**)device);
}
static inline int keymaster2_close(keymaster2_device_t* device) {
return device->common.close(&device->common);
}
__END_DECLS
#endif // ANDROID_HARDWARE_KEYMASTER2_H

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@ -54,6 +54,12 @@ __BEGIN_DECLS
#define KEYMASTER_MODULE_API_VERSION_1_0 HARDWARE_MODULE_API_VERSION(1, 0) #define KEYMASTER_MODULE_API_VERSION_1_0 HARDWARE_MODULE_API_VERSION(1, 0)
#define KEYMASTER_DEVICE_API_VERSION_1_0 HARDWARE_DEVICE_API_VERSION(1, 0) #define KEYMASTER_DEVICE_API_VERSION_1_0 HARDWARE_DEVICE_API_VERSION(1, 0)
/**
* Keymaster 2.0 module version provides third API, slightly modified and extended from 1.0.
*/
#define KEYMASTER_MODULE_API_VERSION_2_0 HARDWARE_MODULE_API_VERSION(2, 0)
#define KEYMASTER_DEVICE_API_VERSION_2_0 HARDWARE_DEVICE_API_VERSION(2, 0)
struct keystore_module { struct keystore_module {
/** /**
* Common methods of the keystore module. This *must* be the first member of keystore_module as * Common methods of the keystore module. This *must* be the first member of keystore_module as

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@ -52,22 +52,25 @@ typedef enum {
*/ */
/* Crypto parameters */ /* Crypto parameters */
KM_TAG_PURPOSE = KM_ENUM_REP | 1, /* keymaster_purpose_t. */ KM_TAG_PURPOSE = KM_ENUM_REP | 1, /* keymaster_purpose_t. */
KM_TAG_ALGORITHM = KM_ENUM | 2, /* keymaster_algorithm_t. */ KM_TAG_ALGORITHM = KM_ENUM | 2, /* keymaster_algorithm_t. */
KM_TAG_KEY_SIZE = KM_UINT | 3, /* Key size in bits. */ KM_TAG_KEY_SIZE = KM_UINT | 3, /* Key size in bits. */
KM_TAG_BLOCK_MODE = KM_ENUM_REP | 4, /* keymaster_block_mode_t. */ KM_TAG_BLOCK_MODE = KM_ENUM_REP | 4, /* keymaster_block_mode_t. */
KM_TAG_DIGEST = KM_ENUM_REP | 5, /* keymaster_digest_t. */ KM_TAG_DIGEST = KM_ENUM_REP | 5, /* keymaster_digest_t. */
KM_TAG_PADDING = KM_ENUM_REP | 6, /* keymaster_padding_t. */ KM_TAG_PADDING = KM_ENUM_REP | 6, /* keymaster_padding_t. */
KM_TAG_CALLER_NONCE = KM_BOOL | 7, /* Allow caller to specify nonce or IV. */ KM_TAG_CALLER_NONCE = KM_BOOL | 7, /* Allow caller to specify nonce or IV. */
KM_TAG_MIN_MAC_LENGTH = KM_UINT | 8, /* Minimum length of MAC or AEAD authentication tag in KM_TAG_MIN_MAC_LENGTH = KM_UINT | 8, /* Minimum length of MAC or AEAD authentication tag in
* bits. */ * bits. */
KM_TAG_KDF = KM_ENUM | 9, /* keymaster_kdf_t */ KM_TAG_KDF = KM_ENUM_REP | 9, /* keymaster_kdf_t (keymaster2) */
KM_TAG_EC_CURVE = KM_ENUM | 10, /* keymaster_ec_curve_t */ KM_TAG_EC_CURVE = KM_ENUM | 10, /* keymaster_ec_curve_t (keymaster2) */
/* Algorithm-specific. */ /* Algorithm-specific. */
KM_TAG_RSA_PUBLIC_EXPONENT = KM_ULONG | 200, KM_TAG_RSA_PUBLIC_EXPONENT = KM_ULONG | 200,
KM_TAG_ECIES_SINGLE_HASH_MODE = KM_BOOL | 201, /* Whether the ephemeral public key is fed into KM_TAG_ECIES_SINGLE_HASH_MODE = KM_BOOL | 201, /* Whether the ephemeral public key is fed into
* the KDF, see 10.2 in http://goo.gl/WbmSSO */ * the KDF */
KM_TAG_INCLUDE_UNIQUE_ID = KM_BOOL | 202, /* If true, attestation certificates for this key
* will contain an application-scoped and
* time-bounded device-unique ID. (keymaster2) */
/* Other hardware-enforced. */ /* Other hardware-enforced. */
KM_TAG_BLOB_USAGE_REQUIREMENTS = KM_ENUM | 301, /* keymaster_key_blob_usage_requirements_t */ KM_TAG_BLOB_USAGE_REQUIREMENTS = KM_ENUM | 301, /* keymaster_key_blob_usage_requirements_t */
@ -108,8 +111,13 @@ typedef enum {
device is powered off. */ device is powered off. */
/* Application access control */ /* Application access control */
KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* Reserved for future use -- ignore */ KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* Specified to indicate key is usable by all
KM_TAG_APPLICATION_ID = KM_BYTES | 601, /* Reserved for fugure use -- ignore */ * applications. */
KM_TAG_APPLICATION_ID = KM_BYTES | 601, /* Byte string identifying the authorized
* application. */
KM_TAG_EXPORTABLE = KM_BOOL | 602, /* If true, private/secret key can be exported, but
* only if all access control requirements for use are
* met. (keymaster2) */
/* /*
* Semantically unenforceable tags, either because they have no specific meaning or because * Semantically unenforceable tags, either because they have no specific meaning or because
@ -120,6 +128,9 @@ typedef enum {
KM_TAG_ORIGIN = KM_ENUM | 702, /* keymaster_key_origin_t. */ KM_TAG_ORIGIN = KM_ENUM | 702, /* keymaster_key_origin_t. */
KM_TAG_ROLLBACK_RESISTANT = KM_BOOL | 703, /* Whether key is rollback-resistant. */ KM_TAG_ROLLBACK_RESISTANT = KM_BOOL | 703, /* Whether key is rollback-resistant. */
KM_TAG_ROOT_OF_TRUST = KM_BYTES | 704, /* Root of trust ID. */ KM_TAG_ROOT_OF_TRUST = KM_BYTES | 704, /* Root of trust ID. */
KM_TAG_OS_VERSION = KM_UINT | 705, /* Version of system (keymaster2) */
KM_TAG_OS_PATCHLEVEL = KM_UINT | 706, /* Patch level of system (keymaster2) */
KM_TAG_UNIQUE_ID = KM_BYTES | 707, /* Used to provide unique ID in attestation */
/* Tags used only to provide data to or receive data from operations */ /* Tags used only to provide data to or receive data from operations */
KM_TAG_ASSOCIATED_DATA = KM_BYTES | 1000, /* Used to provide associated data for AEAD modes. */ KM_TAG_ASSOCIATED_DATA = KM_BYTES | 1000, /* Used to provide associated data for AEAD modes. */
@ -127,7 +138,12 @@ typedef enum {
KM_TAG_AUTH_TOKEN = KM_BYTES | 1002, /* Authentication token that proves secure user KM_TAG_AUTH_TOKEN = KM_BYTES | 1002, /* Authentication token that proves secure user
authentication has been performed. Structure authentication has been performed. Structure
defined in hw_auth_token_t in hw_auth_token.h. */ defined in hw_auth_token_t in hw_auth_token.h. */
KM_TAG_MAC_LENGTH = KM_UINT | 1003, /* MAC or AEAD authentication tag length in bits. */ KM_TAG_MAC_LENGTH = KM_UINT | 1003, /* MAC or AEAD authentication tag length in
* bits. */
KM_TAG_RESET_SINCE_ID_ROTATION = KM_BOOL | 1004, /* Whether the device has beeen factory reset
since the last unique ID rotation. Used for
key attestation. */
} keymaster_tag_t; } keymaster_tag_t;
/** /**
@ -195,16 +211,18 @@ typedef enum {
* Key derivation functions, mostly used in ECIES. * Key derivation functions, mostly used in ECIES.
*/ */
typedef enum { typedef enum {
/* Do not apply a key derivation function; use the raw agreed key */
KM_KDF_NONE = 0,
/* HKDF defined in RFC 5869 with SHA256 */ /* HKDF defined in RFC 5869 with SHA256 */
KM_KDF_RFC5869_SHA256 = 0, KM_KDF_RFC5869_SHA256 = 1,
/* KDF1 defined in ISO 18033-2 with SHA1 */ /* KDF1 defined in ISO 18033-2 with SHA1 */
KM_KDF_ISO18033_1_KDF2_SHA1 = 1, KM_KDF_ISO18033_2_KDF1_SHA1 = 2,
/* KDF1 defined in ISO 18033-2 with SHA256 */ /* KDF1 defined in ISO 18033-2 with SHA256 */
KM_KDF_ISO18033_1_KDF1_SHA256 = 2, KM_KDF_ISO18033_2_KDF1_SHA256 = 3,
/* KDF2 defined in ISO 18033-2 with SHA1 */ /* KDF2 defined in ISO 18033-2 with SHA1 */
KM_KDF_ISO18033_2_KDF2_SHA1 = 3, KM_KDF_ISO18033_2_KDF2_SHA1 = 4,
/* KDF2 defined in ISO 18033-2 with SHA256 */ /* KDF2 defined in ISO 18033-2 with SHA256 */
KM_KDF_ISO18033_2_KDF2_SHA256 = 4, KM_KDF_ISO18033_2_KDF2_SHA256 = 5,
} keymaster_kdf_t; } keymaster_kdf_t;
/** /**
@ -224,8 +242,9 @@ typedef enum {
* hardware-enforced list is guaranteed never to have existed outide the secure hardware. * hardware-enforced list is guaranteed never to have existed outide the secure hardware.
*/ */
typedef enum { typedef enum {
KM_ORIGIN_GENERATED = 0, /* Generated in keymaster */ KM_ORIGIN_GENERATED = 0, /* Generated in keymaster. Should not exist outside the TEE. */
KM_ORIGIN_IMPORTED = 2, /* Imported, origin unknown */ KM_ORIGIN_DERIVED = 1, /* Derived inside keymaster. Likely exists off-device. */
KM_ORIGIN_IMPORTED = 2, /* Imported into keymaster. Existed as cleartext in Android. */
KM_ORIGIN_UNKNOWN = 3, /* Keymaster did not record origin. This value can only be seen on KM_ORIGIN_UNKNOWN = 3, /* Keymaster did not record origin. This value can only be seen on
* keys in a keymaster0 implementation. The keymaster0 adapter uses * keys in a keymaster0 implementation. The keymaster0 adapter uses
* this value to document the fact that it is unkown whether the key * this value to document the fact that it is unkown whether the key
@ -237,7 +256,7 @@ typedef enum {
* for the key to function. For example, key "blobs" which are actually handles referencing * for the key to function. For example, key "blobs" which are actually handles referencing
* encrypted key material stored in the file system cannot be used until the file system is * encrypted key material stored in the file system cannot be used until the file system is
* available, and should have BLOB_REQUIRES_FILE_SYSTEM. Other requirements entries will be added * available, and should have BLOB_REQUIRES_FILE_SYSTEM. Other requirements entries will be added
* as needed for implementations. This type is new in 0_4. * as needed for implementations.
*/ */
typedef enum { typedef enum {
KM_BLOB_STANDALONE = 0, KM_BLOB_STANDALONE = 0,
@ -245,13 +264,14 @@ typedef enum {
} keymaster_key_blob_usage_requirements_t; } keymaster_key_blob_usage_requirements_t;
/** /**
* Possible purposes of a key (or pair). This type is new in 0_4. * Possible purposes of a key (or pair).
*/ */
typedef enum { typedef enum {
KM_PURPOSE_ENCRYPT = 0, KM_PURPOSE_ENCRYPT = 0, /* Usable with RSA, EC and AES keys. */
KM_PURPOSE_DECRYPT = 1, KM_PURPOSE_DECRYPT = 1, /* Usable with RSA, EC and AES keys. */
KM_PURPOSE_SIGN = 2, KM_PURPOSE_SIGN = 2, /* Usable with RSA, EC and HMAC keys. */
KM_PURPOSE_VERIFY = 3, KM_PURPOSE_VERIFY = 3, /* Usable with RSA, EC and HMAC keys. */
KM_PURPOSE_DERIVE_KEY = 4, /* Usable with EC keys. */
} keymaster_purpose_t; } keymaster_purpose_t;
typedef struct { typedef struct {
@ -293,14 +313,18 @@ typedef struct {
size_t key_material_size; size_t key_material_size;
} keymaster_key_blob_t; } keymaster_key_blob_t;
typedef struct {
keymaster_blob_t* entries;
size_t entry_count;
} keymaster_cert_chain_t;
/** /**
* Formats for key import and export. At present, only asymmetric key import/export is supported. * Formats for key import and export.
* In the future this list will expand greatly to accommodate asymmetric key import/export.
*/ */
typedef enum { typedef enum {
KM_KEY_FORMAT_X509 = 0, /* for public key export */ KM_KEY_FORMAT_X509 = 0, /* for public key export */
KM_KEY_FORMAT_PKCS8 = 1, /* for asymmetric key pair import */ KM_KEY_FORMAT_PKCS8 = 1, /* for asymmetric key pair import */
KM_KEY_FORMAT_RAW = 3, /* for symmetric key import */ KM_KEY_FORMAT_RAW = 3, /* for symmetric key import and export*/
} keymaster_key_format_t; } keymaster_key_format_t;
/** /**
@ -372,6 +396,7 @@ typedef enum {
KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH = -59, KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH = -59,
KM_ERROR_UNSUPPORTED_KDF = -60, KM_ERROR_UNSUPPORTED_KDF = -60,
KM_ERROR_UNSUPPORTED_EC_CURVE = -61, KM_ERROR_UNSUPPORTED_EC_CURVE = -61,
KM_ERROR_KEY_REQUIRES_UPGRADE = -62,
KM_ERROR_UNIMPLEMENTED = -100, KM_ERROR_UNIMPLEMENTED = -100,
KM_ERROR_VERSION_MISMATCH = -101, KM_ERROR_VERSION_MISMATCH = -101,
@ -541,6 +566,19 @@ inline void keymaster_free_characteristics(keymaster_key_characteristics_t* char
} }
} }
inline void keymaster_free_cert_chain(keymaster_cert_chain_t* chain) {
if (chain) {
for (size_t i = 0; i < chain->entry_count; ++i) {
free((uint8_t*)chain->entries[i].data);
chain->entries[i].data = NULL;
chain->entries[i].data_length = 0;
}
free(chain->entries);
chain->entries = NULL;
chain->entry_count = 0;
}
}
#ifdef __cplusplus #ifdef __cplusplus
} // extern "C" } // extern "C"
#endif // __cplusplus #endif // __cplusplus