Define keymaster HAL v0.4.
Change-Id: I040412443bbbe25bce3d44759d710b78eac36caa
diff --git a/include/hardware/keymaster.h b/include/hardware/keymaster.h
index 8c5ff14..a6200a5 100644
--- a/include/hardware/keymaster.h
+++ b/include/hardware/keymaster.h
@@ -22,6 +22,7 @@
#include <sys/types.h>
#include <hardware/hardware.h>
+#include <hardware/keymaster_defs.h>
__BEGIN_DECLS
@@ -36,51 +37,19 @@
* Settings for "module_api_version" and "hal_api_version"
* fields in the keymaster_module initialization.
*/
-#define KEYMASTER_HEADER_VERSION 3
+#define KEYMASTER_HEADER_VERSION 4
-#define KEYMASTER_MODULE_API_VERSION_0_2 HARDWARE_MODULE_API_VERSION(0, 2)
-#define KEYMASTER_DEVICE_API_VERSION_0_2 HARDWARE_DEVICE_API_VERSION_2(0, 2, KEYMASTER_HEADER_VERSION)
+#define KEYMASTER_MODULE_API_VERSION_0_2 HARDWARE_MODULE_API_VERSION(0, 2)
+#define KEYMASTER_DEVICE_API_VERSION_0_2 \
+ HARDWARE_DEVICE_API_VERSION_2(0, 2, KEYMASTER_HEADER_VERSION)
-#define KEYMASTER_MODULE_API_VERSION_0_3 HARDWARE_MODULE_API_VERSION(0, 3)
-#define KEYMASTER_DEVICE_API_VERSION_0_3 HARDWARE_DEVICE_API_VERSION_2(0, 3, KEYMASTER_HEADER_VERSION)
+#define KEYMASTER_MODULE_API_VERSION_0_3 HARDWARE_MODULE_API_VERSION(0, 3)
+#define KEYMASTER_DEVICE_API_VERSION_0_3 \
+ HARDWARE_DEVICE_API_VERSION_2(0, 3, KEYMASTER_HEADER_VERSION)
-/**
- * Flags for keymaster_device::flags
- */
-enum {
- /*
- * Indicates this keymaster implementation does not have hardware that
- * keeps private keys out of user space.
- *
- * This should not be implemented on anything other than the default
- * implementation.
- */
- KEYMASTER_SOFTWARE_ONLY = 1 << 0,
-
- /*
- * This indicates that the key blobs returned via all the primitives
- * are sufficient to operate on their own without the trusted OS
- * querying userspace to retrieve some other data. Key blobs of
- * this type are normally returned encrypted with a
- * Key Encryption Key (KEK).
- *
- * This is currently used by "vold" to know whether the whole disk
- * encryption secret can be unwrapped without having some external
- * service started up beforehand since the "/data" partition will
- * be unavailable at that point.
- */
- KEYMASTER_BLOBS_ARE_STANDALONE = 1 << 1,
-
- /*
- * Indicates that the keymaster module supports DSA keys.
- */
- KEYMASTER_SUPPORTS_DSA = 1 << 2,
-
- /*
- * Indicates that the keymaster module supports EC keys.
- */
- KEYMASTER_SUPPORTS_EC = 1 << 3,
-};
+#define KEYMASTER_MODULE_API_VERSION_0_4 HARDWARE_MODULE_API_VERSION(0, 4)
+#define KEYMASTER_DEVICE_API_VERSION_0_4 \
+ HARDWARE_DEVICE_API_VERSION_2(0, 4, KEYMASTER_HEADER_VERSION)
struct keystore_module {
/**
@@ -93,82 +62,6 @@
};
/**
- * Asymmetric key pair types.
- */
-typedef enum {
- TYPE_RSA = 1,
- TYPE_DSA = 2,
- TYPE_EC = 3,
-} keymaster_keypair_t;
-
-/**
- * Parameters needed to generate an RSA key.
- */
-typedef struct {
- uint32_t modulus_size;
- uint64_t public_exponent;
-} keymaster_rsa_keygen_params_t;
-
-/**
- * Parameters needed to generate a DSA key.
- */
-typedef struct {
- uint32_t key_size;
- uint32_t generator_len;
- uint32_t prime_p_len;
- uint32_t prime_q_len;
- const uint8_t* generator;
- const uint8_t* prime_p;
- const uint8_t* prime_q;
-} keymaster_dsa_keygen_params_t;
-
-/**
- * Parameters needed to generate an EC key.
- *
- * Field size is the only parameter in version 2. The sizes correspond to these required curves:
- *
- * 192 = NIST P-192
- * 224 = NIST P-224
- * 256 = NIST P-256
- * 384 = NIST P-384
- * 521 = NIST P-521
- *
- * The parameters for these curves are available at: http://www.nsa.gov/ia/_files/nist-routines.pdf
- * in Chapter 4.
- */
-typedef struct {
- uint32_t field_size;
-} keymaster_ec_keygen_params_t;
-
-/**
- * Digest type.
- */
-typedef enum {
- DIGEST_NONE,
-} keymaster_digest_t;
-
-/**
- * Type of padding used for RSA operations.
- */
-typedef enum {
- PADDING_NONE,
-} keymaster_rsa_padding_t;
-
-
-typedef struct {
- keymaster_digest_t digest_type;
-} keymaster_dsa_sign_params_t;
-
-typedef struct {
- keymaster_digest_t digest_type;
-} keymaster_ec_sign_params_t;
-
-typedef struct {
- keymaster_digest_t digest_type;
- keymaster_rsa_padding_t padding_type;
-} keymaster_rsa_sign_params_t;
-
-/**
* The parameters that can be set for a given keymaster implementation.
*/
struct keymaster_device {
@@ -194,52 +87,49 @@
void* context;
/**
- * Generates a public and private key. The key-blob returned is opaque
- * and must subsequently provided for signing and verification.
+ * \deprecated Generates a public and private key. The key-blob returned is opaque and must
+ * subsequently provided for signing and verification.
*
* Returns: 0 on success or an error code less than 0.
*/
- int (*generate_keypair)(const struct keymaster_device* dev,
- const keymaster_keypair_t key_type, const void* key_params,
- uint8_t** key_blob, size_t* key_blob_length);
+ int (*generate_keypair)(const struct keymaster_device* dev, const keymaster_keypair_t key_type,
+ const void* key_params, uint8_t** key_blob, size_t* key_blob_length);
/**
- * Imports a public and private key pair. The imported keys will be in
- * PKCS#8 format with DER encoding (Java standard). The key-blob
- * returned is opaque and will be subsequently provided for signing
- * and verification.
+ * \deprecated Imports a public and private key pair. The imported keys will be in PKCS#8 format
+ * with DER encoding (Java standard). The key-blob returned is opaque and will be subsequently
+ * provided for signing and verification.
*
* Returns: 0 on success or an error code less than 0.
*/
- int (*import_keypair)(const struct keymaster_device* dev,
- const uint8_t* key, const size_t key_length,
- uint8_t** key_blob, size_t* key_blob_length);
+ int (*import_keypair)(const struct keymaster_device* dev, const uint8_t* key,
+ const size_t key_length, uint8_t** key_blob, size_t* key_blob_length);
/**
- * Gets the public key part of a key pair. The public key must be in
- * X.509 format (Java standard) encoded byte array.
+ * \deprecated Gets the public key part of a key pair. The public key must be in X.509 format
+ * (Java standard) encoded byte array.
*
- * Returns: 0 on success or an error code less than 0.
- * On error, x509_data should not be allocated.
+ * Returns: 0 on success or an error code less than 0. On error, x509_data
+ * should not be allocated.
*/
- int (*get_keypair_public)(const struct keymaster_device* dev,
- const uint8_t* key_blob, const size_t key_blob_length,
- uint8_t** x509_data, size_t* x509_data_length);
+ int (*get_keypair_public)(const struct keymaster_device* dev, const uint8_t* key_blob,
+ const size_t key_blob_length, uint8_t** x509_data,
+ size_t* x509_data_length);
/**
- * Deletes the key pair associated with the key blob.
+ * \deprecated Deletes the key pair associated with the key blob.
*
* This function is optional and should be set to NULL if it is not
* implemented.
*
* Returns 0 on success or an error code less than 0.
*/
- int (*delete_keypair)(const struct keymaster_device* dev,
- const uint8_t* key_blob, const size_t key_blob_length);
+ int (*delete_keypair)(const struct keymaster_device* dev, const uint8_t* key_blob,
+ const size_t key_blob_length);
/**
- * Deletes all keys in the hardware keystore. Used when keystore is
- * reset completely.
+ * \deprecated Deletes all keys in the hardware keystore. Used when keystore is reset
+ * completely.
*
* This function is optional and should be set to NULL if it is not
* implemented.
@@ -249,45 +139,515 @@
int (*delete_all)(const struct keymaster_device* dev);
/**
- * Signs data using a key-blob generated before. This can use either
- * an asymmetric key or a secret key.
+ * \deprecated Signs data using a key-blob generated before. This can use either an asymmetric
+ * key or a secret key.
*
* Returns: 0 on success or an error code less than 0.
*/
- int (*sign_data)(const struct keymaster_device* dev,
- const void* signing_params,
- const uint8_t* key_blob, const size_t key_blob_length,
- const uint8_t* data, const size_t data_length,
- uint8_t** signed_data, size_t* signed_data_length);
+ int (*sign_data)(const struct keymaster_device* dev, const void* signing_params,
+ const uint8_t* key_blob, const size_t key_blob_length, const uint8_t* data,
+ const size_t data_length, uint8_t** signed_data, size_t* signed_data_length);
/**
- * Verifies data signed with a key-blob. This can use either
- * an asymmetric key or a secret key.
+ * \deprecated Verifies data signed with a key-blob. This can use either an asymmetric key or a
+ * secret key.
*
* Returns: 0 on successful verification or an error code less than 0.
*/
- int (*verify_data)(const struct keymaster_device* dev,
- const void* signing_params,
- const uint8_t* key_blob, const size_t key_blob_length,
- const uint8_t* signed_data, const size_t signed_data_length,
- const uint8_t* signature, const size_t signature_length);
+ int (*verify_data)(const struct keymaster_device* dev, const void* signing_params,
+ const uint8_t* key_blob, const size_t key_blob_length,
+ const uint8_t* signed_data, const size_t signed_data_length,
+ const uint8_t* signature, const size_t signature_length);
+
+ /**
+ * Gets algorithms supported.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[out] algorithms Array of algorithms supported. The caller takes ownership of the
+ * array and must free() it.
+ *
+ * \param[out] algorithms_length Length of \p algorithms.
+ */
+ keymaster_error_t (*get_supported_algorithms)(const struct keymaster_device* dev,
+ keymaster_algorithm_t** algorithms,
+ size_t* algorithms_length);
+
+ /**
+ * Gets the block modes supported for the specified algorithm.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] algorithm The algorithm for which supported modes will be returned.
+ *
+ * \param[out] modes Array of modes supported. The caller takes ownership of the array and must
+ * free() it.
+ *
+ * \param[out] modes_length Length of \p modes.
+ */
+ keymaster_error_t (*get_supported_block_modes)(const struct keymaster_device* dev,
+ keymaster_algorithm_t algorithm,
+ keymaster_purpose_t purpose,
+ keymaster_block_mode_t** modes,
+ size_t* modes_length);
+
+ /**
+ * Gets the padding modes supported for the specified algorithm. Caller assumes ownership of
+ * the allocated array.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] algorithm The algorithm for which supported padding modes will be returned.
+ *
+ * \param[out] modes Array of padding modes supported. The caller takes ownership of the array
+ * and must free() it.
+ *
+ * \param[out] modes_length Length of \p modes.
+ */
+ keymaster_error_t (*get_supported_padding_modes)(const struct keymaster_device* dev,
+ keymaster_algorithm_t algorithm,
+ keymaster_purpose_t purpose,
+ keymaster_padding_t** modes,
+ size_t* modes_length);
+
+ /**
+ * Gets the digests supported for the specified algorithm. Caller assumes ownership of the
+ * allocated array.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] algorithm The algorithm for which supported digests will be returned.
+ *
+ * \param[out] digests Array of digests supported. The caller takes ownership of the array and
+ * must free() it.
+ *
+ * \param[out] digests_length Length of \p digests.
+ */
+ keymaster_error_t (*get_supported_digests)(const struct keymaster_device* dev,
+ keymaster_algorithm_t algorithm,
+ keymaster_purpose_t purpose,
+ keymaster_digest_t** digests,
+ size_t* digests_length);
+
+ /**
+ * Gets the key import formats supported for keys of the specified algorithm. Caller assumes
+ * ownership of the allocated array.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] algorithm The algorithm for which supported formats will be returned.
+ *
+ * \param[out] formats Array of formats supported. The caller takes ownership of the array and
+ * must free() it.
+ *
+ * \param[out] formats_length Length of \p formats.
+ */
+ keymaster_error_t (*get_supported_import_formats)(const struct keymaster_device* dev,
+ keymaster_algorithm_t algorithm,
+ keymaster_key_format_t** formats,
+ size_t* formats_length);
+
+ /**
+ * Gets the key export formats supported for keys of the specified algorithm. Caller assumes
+ * ownership of the allocated array.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] algorithm The algorithm for which supported formats will be returned.
+ *
+ * \param[out] formats Array of formats supported. The caller takes ownership of the array and
+ * must free() it.
+ *
+ * \param[out] formats_length Length of \p formats.
+ */
+ keymaster_error_t (*get_supported_export_formats)(const struct keymaster_device* dev,
+ keymaster_algorithm_t algorithm,
+ keymaster_key_format_t** formats,
+ size_t* formats_length);
+
+ /**
+ * 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 keymaster_device* dev, 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;
+ * - KM_TAG_USER_ID or KM_TAG_ALL_USERS;
+ * - KM_TAG_USER_AUTH_ID or KM_TAG_NO_AUTH_REQUIRED;
+ * - KM_TAG_APPLICATION_ID or KM_TAG_ALL_APPLICATIONS; and
+ * - KM_TAG_ORIGINATION_EXPIRE_DATETIME
+ *
+ * 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 will take default values if unspecified:
+ *
+ * - KM_TAG_KEY_SIZE defaults to a recommended key size for the specified algorithm.
+ *
+ * - KM_TAG_USAGE_EXPIRE_DATETIME defaults to the value of KM_TAG_ORIGINATION_EXPIRE_DATETIME.
+ *
+ * - KM_TAG_ACTIVE_DATETIME will default to the value of KM_TAG_CREATION_DATETIME
+ *
+ * - KM_TAG_ROOT_OF_TRUST will default to the current root of trust.
+ *
+ * - KM_TAG_{RSA|DSA|DH}_* will default to values appropriate for the specified key size.
+ *
+ * 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 parameters.
+ *
+ * \param[in] params_count Length of \p params.
+ *
+ * \param[out] key_blob returns the generated key. If \p key_blob is NULL, no key is generated,
+ * but the characteristics of the key that would be generated are returned. The caller assumes
+ * ownership key_blob->key_material and must free() it.
+ *
+ * \param[out] characteristics returns the characteristics of the key that was, or would be,
+ * generated, if non-NULL. The caller assumes ownership, and the object must be freed 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 keymaster_device* dev,
+ const keymaster_key_param_t* params, size_t params_count,
+ keymaster_key_blob_t* key_blob,
+ keymaster_key_characteristics_t** characteristics);
+
+ /**
+ * Returns the characteristics of the specified key, or NULL 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. Those values are not
+ * included in the returned characteristics. Caller assumes ownership of the allocated
+ * characteristics object, which must be deallocated with keymaster_free_characteristics().
+ *
+ * Note that KM_TAG_ROOT_OF_TRUST, 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.
+ */
+ keymaster_error_t (*get_key_characteristics)(const struct keymaster_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);
+
+ /**
+ * Change a key's authorizations.
+ *
+ * Update the authorizations associated with key_blob to the list specified in new_params, which
+ * must contain the complete set of authorizations desired (hw_enforced and sw_enforced). Tags
+ * will be added, removed and/or updated only if the appropriate KM_TAG_RESCOPING_ADD and
+ * KM_TAG_RESCOPING_DEL tags exist in the key's authorizations, otherwise
+ * KM_ERROR_INVALID_RESCOPING will be returned and no changes will be made.
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] new_params The new authorization list to be associated with the key.
+ *
+ * \param[in] new_params_count The number of entries in \p new_params.
+ *
+ * \param[in] key_blob The key to update.
+ *
+ * \param[in] client_id The client ID associated with the key, or NULL if none is associated.
+ *
+ * \param[in] app_data The application data associated with the key, or NULL if none is
+ * associated.
+ *
+ * \param[out] rescoped_key_blob The key blob with the updated authorizations, if successful.
+ * The caller assumes ownership of rescoped_key_blob->key_material and must free() it.
+ *
+ * \param[out] characteristics If not null will contain the new key authorizations, divided into
+ * hw_enforced and sw_enforced lists. The caller takes ownership and must call
+ * keymaster_free_characteristics() to free.
+ */
+ keymaster_error_t (*rescope)(const struct keymaster_device* dev,
+ const keymaster_key_param_t* new_params, size_t new_params_count,
+ const keymaster_key_blob_t* key_blob,
+ const keymaster_blob_t* client_id,
+ const keymaster_blob_t* app_data,
+ const keymaster_key_blob_t* rescoped_key_blob,
+ 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. Some values that are always required for import of
+ * useful keys are:
+ *
+ * - KM_TAG_PURPOSE;
+ *
+ * - KM_TAG_USER_ID
+ *
+ * - KM_TAG_USER_AUTH_ID;
+ *
+ * - KM_TAG_APPLICATION_ID or KM_TAG_ALL_APPLICATIONS;
+ *
+ * - KM_TAG_PRIVKEY_EXPIRE_DATETIME.
+ *
+ * KM_TAG_AUTH_TIMEOUT should generally be specified. If unspecified, the user will have to
+ * authenticate for every use, unless KM_TAG_USER_AUTH_ID is set to
+ * KM_NO_AUTHENTICATION_REQUIRED.
+ *
+ * The following tags will take default values if unspecified:
+ *
+ * - KM_TAG_PUBKEY_EXPIRE_DATETIME will default to the value for KM_TAG_PRIVKEY_EXPIRE_DATETIME.
+ *
+ * - KM_TAG_ACTIVE_DATETIME will default to the value of KM_TAG_CREATION_DATETIME
+ *
+ * - KM_TAG_ROOT_OF_TRUST will default to the current root of trust.
+ *
+ * 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 and must deallocate with keymaster_free_characteristics().
+ */
+ keymaster_error_t (*import_key)(const struct keymaster_device* dev,
+ const keymaster_key_param_t* params, size_t params_count,
+ keymaster_key_format_t key_format, const uint8_t* key_data,
+ size_t key_data_length, keymaster_key_blob_t* key_blob,
+ keymaster_key_characteristics_t** characteristics);
+
+ /**
+ * Exports a public key, returning a byte array in the specified format.
+ *
+ * \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[out] export_data The exported key material. The caller assumes ownership.
+ *
+ * \param[out] export_data_length The length of \p export_data.
+ */
+ keymaster_error_t (*export_key)(const struct keymaster_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, uint8_t** export_data,
+ size_t* export_data_length);
+
+ /**
+ * 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 (though rescoped versions may
+ * exist, and if so will be usable). 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 keymaster_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.
+ *
+ * Returns 0 on success or an error code less than 0.
+ */
+ int (*delete_all_keys)(const struct keymaster_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 will leak internal state space or other internal resources and will
+ * eventually cause begin() to return KM_ERROR_TOO_MANY_OPERATIONS when it runs out of space for
+ * operations.
+ *
+ * \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.
+ *
+ * \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] params Additional parameters for the operation. This is typically used to provide
+ * client ID information, with tags KM_TAG_APPLICATION_ID and KM_TAG_APPLICATION_DATA. If the
+ * client information associated with the key is not provided, begin() will fail and return
+ * KM_ERROR_INVALID_KEY_BLOB. Less commonly, \params can be used to provide AEAD additional
+ * data and chunk size with KM_TAG_ADDITIONAL_DATA or KM_TAG_CHUNK_SIZE respectively.
+ *
+ * \param[in] params_count The number of entries in \p params.
+ *
+ * \param[out] out_params Array of output parameters. The caller takes ownership of the output
+ * parametes array and must free it. out_params may be set to NULL if no output parameters are
+ * expected. If NULL, and output paramaters are generated, begin() will return
+ * KM_ERROR_OUTPUT_PARAMETER_NULL.
+ *
+ * \param[out] out_params_count The length of out_params.
+ *
+ * \param[out] operation_handle The newly-created operation handle which must be passed to
+ * update(), finish() or abort().
+ */
+ keymaster_error_t (*begin)(const struct keymaster_device* dev, keymaster_purpose_t purpose,
+ const keymaster_key_blob_t* key, const keymaster_key_param_t* params,
+ size_t params_count, keymaster_key_param_t** out_params,
+ size_t* out_params_count,
+ keymaster_operation_handle_t* operation_handle);
+
+ /**
+ * Get an estimate of the output that will be generated by calling update() with the specified
+ * number of input bytes, followed by finish(). The estimate may not be exact, but is
+ * guaranteed not to be smaller than sum of the output lengths from update() and finish(). The
+ * estimate takes into account input data already provided.
+ *
+ * \param[in] input_length The number of additional input bytes to be processed.
+ *
+ * \param[out] output_estimate The length of the output that will be produced.
+ */
+ keymaster_error_t (*get_output_size)(size_t input_length, size_t* output_estimate);
+
+ /**
+ * 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.
+ *
+ * Not all of the data provided in the data buffer may be consumed. 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] 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 data_consumed.
+ *
+ * \param[in] input_length Length of \p input.
+ *
+ * \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] output The output data, if any. The caller assumes ownership of the allocated
+ * buffer. If output is NULL then NO input data is consumed and no output is produced, but
+ * *output_length is set to an estimate of the size that would have been produced by this
+ * update() and a subsequent finish().
+ *
+ * \param[out] output_length The length of the output buffer.
+ *
+ * Note that update() may not provide any output, in which case *output_length will be zero, and
+ * *output may be either NULL or zero-length (so the caller should always free() it).
+ */
+ keymaster_error_t (*update)(const struct keymaster_device* dev,
+ keymaster_operation_handle_t operation_handle, const uint8_t* input,
+ size_t input_length, size_t* input_consumed, uint8_t** output,
+ size_t* output_length);
+
+ /**
+ * Finalizes a cryptographic operation begun with begin() and invalidates operation_handle
+ * (except in the insufficient buffer case, detailed below).
+ *
+ * \param[in] dev The keymaster device structure.
+ *
+ * \param[in] operation_handle The operation handle returned by begin(). This handle will be
+ * invalidated.
+ *
+ * \param[in] signature The signature to be verified if the purpose specified in the begin()
+ * call was KM_PURPOSE_VERIFY.
+ *
+ * \param[in] signature_length The length of \p signature.
+ *
+ * \param[out] output The output data, if any. The caller assumes ownership of the allocated
+ * buffer.
+ *
+ * \param[out] output_length The length of the output 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 keymaster_device* dev,
+ keymaster_operation_handle_t operation_handle,
+ const uint8_t* signature, size_t signature_length, uint8_t** output,
+ size_t* output_length);
+
+ /**
+ * Aborts a cryptographic operation begun with begin(), freeing all internal resources and
+ * invalidating operation_handle.
+ */
+ keymaster_error_t (*abort)(const struct keymaster_device* dev,
+ keymaster_operation_handle_t operation_handle);
};
typedef struct keymaster_device keymaster_device_t;
-
/* Convenience API for opening and closing keymaster devices */
-static inline int keymaster_open(const struct hw_module_t* module,
- keymaster_device_t** device)
-{
- int rc = module->methods->open(module, KEYSTORE_KEYMASTER,
- (struct hw_device_t**) device);
-
- return rc;
+static inline int keymaster_open(const struct hw_module_t* module, keymaster_device_t** device) {
+ return module->methods->open(module, KEYSTORE_KEYMASTER, (struct hw_device_t**)device);
}
-static inline int keymaster_close(keymaster_device_t* device)
-{
+static inline int keymaster_close(keymaster_device_t* device) {
return device->common.close(&device->common);
}