diff --git a/include/hardware/keymaster2.h b/include/hardware/keymaster2.h
new file mode 100644
index 0000000..dcde30e
--- /dev/null
+++ b/include/hardware/keymaster2.h
@@ -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
diff --git a/include/hardware/keymaster_common.h b/include/hardware/keymaster_common.h
index 772d7e4..c79c122 100644
--- a/include/hardware/keymaster_common.h
+++ b/include/hardware/keymaster_common.h
@@ -54,6 +54,12 @@
 #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)
 
+/**
+ * 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 {
     /**
      * Common methods of the keystore module.  This *must* be the first member of keystore_module as
diff --git a/include/hardware/keymaster_defs.h b/include/hardware/keymaster_defs.h
index 27cef37..c0ca514 100644
--- a/include/hardware/keymaster_defs.h
+++ b/include/hardware/keymaster_defs.h
@@ -52,22 +52,25 @@
      */
 
     /* Crypto parameters */
-    KM_TAG_PURPOSE = KM_ENUM_REP | 1,      /* keymaster_purpose_t. */
-    KM_TAG_ALGORITHM = KM_ENUM | 2,        /* keymaster_algorithm_t. */
-    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_DIGEST = KM_ENUM_REP | 5,       /* keymaster_digest_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_MIN_MAC_LENGTH = KM_UINT | 8,   /* Minimum length of MAC or AEAD authentication tag in
-                                            * bits. */
-    KM_TAG_KDF = KM_ENUM | 9,              /* keymaster_kdf_t */
-    KM_TAG_EC_CURVE = KM_ENUM | 10,        /* keymaster_ec_curve_t */
+    KM_TAG_PURPOSE = KM_ENUM_REP | 1,    /* keymaster_purpose_t. */
+    KM_TAG_ALGORITHM = KM_ENUM | 2,      /* keymaster_algorithm_t. */
+    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_DIGEST = KM_ENUM_REP | 5,     /* keymaster_digest_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_MIN_MAC_LENGTH = KM_UINT | 8, /* Minimum length of MAC or AEAD authentication tag in
+                                          * bits. */
+    KM_TAG_KDF = KM_ENUM_REP | 9,        /* keymaster_kdf_t (keymaster2) */
+    KM_TAG_EC_CURVE = KM_ENUM | 10,      /* keymaster_ec_curve_t (keymaster2) */
 
     /* Algorithm-specific. */
     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
-                                                    *  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. */
     KM_TAG_BLOB_USAGE_REQUIREMENTS = KM_ENUM | 301, /* keymaster_key_blob_usage_requirements_t */
@@ -108,8 +111,13 @@
                                                    device is powered off. */
 
     /* Application access control */
-    KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* Reserved for future use -- ignore */
-    KM_TAG_APPLICATION_ID = KM_BYTES | 601,  /* Reserved for fugure use -- ignore */
+    KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* Specified to indicate key is usable by all
+                                              * 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
@@ -120,6 +128,9 @@
     KM_TAG_ORIGIN = KM_ENUM | 702,             /* keymaster_key_origin_t. */
     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_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 */
     KM_TAG_ASSOCIATED_DATA = KM_BYTES | 1000, /* Used to provide associated data for AEAD modes. */
@@ -127,7 +138,12 @@
     KM_TAG_AUTH_TOKEN = KM_BYTES | 1002,      /* Authentication token that proves secure user
                                                  authentication has been performed.  Structure
                                                  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;
 
 /**
@@ -195,16 +211,18 @@
  * Key derivation functions, mostly used in ECIES.
  */
 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 */
-    KM_KDF_RFC5869_SHA256 = 0,
+    KM_KDF_RFC5869_SHA256 = 1,
     /* 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 */
-    KM_KDF_ISO18033_1_KDF1_SHA256 = 2,
+    KM_KDF_ISO18033_2_KDF1_SHA256 = 3,
     /* 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 */
-    KM_KDF_ISO18033_2_KDF2_SHA256 = 4,
+    KM_KDF_ISO18033_2_KDF2_SHA256 = 5,
 } keymaster_kdf_t;
 
 /**
@@ -224,8 +242,9 @@
  * hardware-enforced list is guaranteed never to have existed outide the secure hardware.
  */
 typedef enum {
-    KM_ORIGIN_GENERATED = 0, /* Generated in keymaster */
-    KM_ORIGIN_IMPORTED = 2,  /* Imported, origin unknown */
+    KM_ORIGIN_GENERATED = 0, /* Generated in keymaster.  Should not exist outside the TEE. */
+    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
                               * keys in a keymaster0 implementation.  The keymaster0 adapter uses
                               * this value to document the fact that it is unkown whether the key
@@ -237,7 +256,7 @@
  * 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
  * 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 {
     KM_BLOB_STANDALONE = 0,
@@ -245,13 +264,14 @@
 } 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 {
-    KM_PURPOSE_ENCRYPT = 0,
-    KM_PURPOSE_DECRYPT = 1,
-    KM_PURPOSE_SIGN = 2,
-    KM_PURPOSE_VERIFY = 3,
+    KM_PURPOSE_ENCRYPT = 0,    /* Usable with RSA, EC and AES keys. */
+    KM_PURPOSE_DECRYPT = 1,    /* Usable with RSA, EC and AES keys. */
+    KM_PURPOSE_SIGN = 2,       /* Usable with RSA, EC and HMAC keys. */
+    KM_PURPOSE_VERIFY = 3,     /* Usable with RSA, EC and HMAC keys. */
+    KM_PURPOSE_DERIVE_KEY = 4, /* Usable with EC keys. */
 } keymaster_purpose_t;
 
 typedef struct {
@@ -293,14 +313,18 @@
     size_t key_material_size;
 } 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.
- * In the future this list will expand greatly to accommodate asymmetric key import/export.
+ * Formats for key import and export.
  */
 typedef enum {
     KM_KEY_FORMAT_X509 = 0,  /* for public key export */
     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;
 
 /**
@@ -372,6 +396,7 @@
     KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH = -59,
     KM_ERROR_UNSUPPORTED_KDF = -60,
     KM_ERROR_UNSUPPORTED_EC_CURVE = -61,
+    KM_ERROR_KEY_REQUIRES_UPGRADE = -62,
 
     KM_ERROR_UNIMPLEMENTED = -100,
     KM_ERROR_VERSION_MISMATCH = -101,
@@ -542,6 +567,19 @@
     }
 }
 
+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
 }  // extern "C"
 #endif  // __cplusplus