crypto/ext4crypt/Keymaster3.cpp - android_bootable_recovery - Gitiles

 /*
  * Copyright (C) 2016 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.
  */

 #include "Keymaster3.h"

 //#include <android-base/logging.h>
 #include <keystore/keymaster_tags.h>
 #include <keystore/authorization_set.h>
 #include <keystore/keystore_hidl_support.h>

 #include <iostream>
 #define ERROR 1
 #define LOG(x) std::cout

 using namespace ::keystore;
 using android::hardware::hidl_string;

 namespace android {
 namespace vold {

 KeymasterOperation::~KeymasterOperation() {
     if (mDevice.get()) mDevice->abort(mOpHandle);
 }

 bool KeymasterOperation::updateCompletely(const std::string& input, std::string* output) {
     if (output)
         output->clear();
     auto it = input.begin();
     uint32_t inputConsumed;

     ErrorCode km_error;
     auto hidlCB = [&] (ErrorCode ret, uint32_t _inputConsumed,
             const hidl_vec<KeyParameter>& /*ignored*/, const hidl_vec<uint8_t>& _output) {
         km_error = ret;
         if (km_error != ErrorCode::OK) return;
         inputConsumed = _inputConsumed;
         if (output)
             output->append(reinterpret_cast<const char*>(&_output[0]), _output.size());
     };

     while (it != input.end()) {
         size_t toRead = static_cast<size_t>(input.end() - it);
         auto inputBlob = blob2hidlVec(reinterpret_cast<const uint8_t*>(&*it), toRead);
         auto error = mDevice->update(mOpHandle, hidl_vec<KeyParameter>(), inputBlob, hidlCB);
         if (!error.isOk()) {
             LOG(ERROR) << "update failed: " << error.description() << "\n";
             mDevice = nullptr;
             return false;
         }
         if (km_error != ErrorCode::OK) {
             LOG(ERROR) << "update failed, code " << int32_t(km_error) << "\n";
             mDevice = nullptr;
             return false;
         }
         if (inputConsumed > toRead) {
             LOG(ERROR) << "update reported too much input consumed\n";
             mDevice = nullptr;
             return false;
         }
         it += inputConsumed;
     }
     return true;
 }

 bool KeymasterOperation::finish(std::string* output) {
     ErrorCode km_error;
     auto hidlCb = [&] (ErrorCode ret, const hidl_vec<KeyParameter>& /*ignored*/,
             const hidl_vec<uint8_t>& _output) {
         km_error = ret;
         if (km_error != ErrorCode::OK) return;
         if (output)
             output->assign(reinterpret_cast<const char*>(&_output[0]), _output.size());
     };
     auto error = mDevice->finish(mOpHandle, hidl_vec<KeyParameter>(), hidl_vec<uint8_t>(),
             hidl_vec<uint8_t>(), hidlCb);
     mDevice = nullptr;
     if (!error.isOk()) {
         LOG(ERROR) << "finish failed: " << error.description() << "\n";
         return false;
     }
     if (km_error != ErrorCode::OK) {
         LOG(ERROR) << "finish failed, code " << int32_t(km_error) << "\n";
         return false;
     }
     return true;
 }

 Keymaster::Keymaster() {
     mDevice = ::android::hardware::keymaster::V3_0::IKeymasterDevice::getService();
 }

 /*bool Keymaster::generateKey(const AuthorizationSet& inParams, std::string* key) {
     ErrorCode km_error;
     auto hidlCb = [&] (ErrorCode ret, const hidl_vec<uint8_t>& keyBlob,
             const KeyCharacteristics& /*ignored* /) {
         km_error = ret;
         if (km_error != ErrorCode::OK) return;
         if (key)
             key->assign(reinterpret_cast<const char*>(&keyBlob[0]), keyBlob.size());
     };

     auto error = mDevice->generateKey(inParams.hidl_data(), hidlCb);
     if (!error.isOk()) {
         LOG(ERROR) << "generate_key failed: " << error.description() << "\n";
         return false;
     }
     if (km_error != ErrorCode::OK) {
         LOG(ERROR) << "generate_key failed, code " << int32_t(km_error) << "\n";
         return false;
     }
     return true;
 }*/

 bool Keymaster::deleteKey(const std::string& key) {
 	LOG(ERROR) << "NOT deleting key in TWRP\n";
 	return false;
     /*auto keyBlob = blob2hidlVec(key);
     auto error = mDevice->deleteKey(keyBlob);
     if (!error.isOk()) {
         LOG(ERROR) << "delete_key failed: " << error.description() << "\n";
         return false;
     }
     if (ErrorCode(error) != ErrorCode::OK) {
         LOG(ERROR) << "delete_key failed, code " << uint32_t(ErrorCode(error)) << "\n";
         return false;
     }
     return true;*/
 }

 bool Keymaster::upgradeKey(const std::string& oldKey, const AuthorizationSet& inParams,
                            std::string* newKey) {
     auto oldKeyBlob = blob2hidlVec(oldKey);
     ErrorCode km_error;
     auto hidlCb = [&] (ErrorCode ret, const hidl_vec<uint8_t>& upgradedKeyBlob) {
         km_error = ret;
         if (km_error != ErrorCode::OK) return;
         if (newKey)
             newKey->assign(reinterpret_cast<const char*>(&upgradedKeyBlob[0]),
                     upgradedKeyBlob.size());
     };
     auto error = mDevice->upgradeKey(oldKeyBlob, inParams.hidl_data(), hidlCb);
     if (!error.isOk()) {
         LOG(ERROR) << "upgrade_key failed: " << error.description() << "\n";
         return false;
     }
     if (km_error != ErrorCode::OK) {
         LOG(ERROR) << "upgrade_key failed, code " << int32_t(km_error) << "\n";
         return false;
     }
     return true;
 }

 KeymasterOperation Keymaster::begin(KeyPurpose purpose, const std::string& key,
                                     const AuthorizationSet& inParams,
                                     AuthorizationSet* outParams) {
     auto keyBlob = blob2hidlVec(key);
     uint64_t mOpHandle;
     ErrorCode km_error;

     auto hidlCb = [&] (ErrorCode ret, const hidl_vec<KeyParameter>& _outParams,
             uint64_t operationHandle) {
         km_error = ret;
         if (km_error != ErrorCode::OK) return;
         if (outParams)
             *outParams = _outParams;
         mOpHandle = operationHandle;
     };

     auto error = mDevice->begin(purpose, keyBlob, inParams.hidl_data(), hidlCb);
     if (!error.isOk()) {
         LOG(ERROR) << "begin failed: " << error.description() << "\n";
         return KeymasterOperation(ErrorCode::UNKNOWN_ERROR);
     }
     if (km_error != ErrorCode::OK) {
         LOG(ERROR) << "begin failed, code " << int32_t(km_error) << "\n";
         return KeymasterOperation(km_error);
     }
     return KeymasterOperation(mDevice, mOpHandle);
 }
 bool Keymaster::isSecure() {
     bool _isSecure = false;
     auto rc = mDevice->getHardwareFeatures(
             [&] (bool isSecure, bool, bool, bool, bool, const hidl_string&, const hidl_string&) {
                 _isSecure = isSecure; });
     return rc.isOk() && _isSecure;
 }

 }  // namespace vold
 }  // namespace android

 using namespace ::android::vold;

 /*
 int keymaster_compatibility_cryptfs_scrypt() {
     Keymaster dev;
     if (!dev) {
         LOG(ERROR) << "Failed to initiate keymaster session\n";
         return -1;
     }
     return dev.isSecure();
 }
 */

 /*int keymaster_create_key_for_cryptfs_scrypt(uint32_t rsa_key_size,
                                             uint64_t rsa_exponent,
                                             uint32_t ratelimit,
                                             uint8_t* key_buffer,
                                             uint32_t key_buffer_size,
                                             uint32_t* key_out_size)
 {
     Keymaster dev;
     std::string key;
     if (!dev) {
         LOG(ERROR) << "Failed to initiate keymaster session\n";
         return -1;
     }
     if (!key_buffer || !key_out_size) {
         LOG(ERROR) << __FILE__ << ":" << __LINE__ << ":Invalid argument\n";
         return -1;
     }
     if (key_out_size) {
         *key_out_size = 0;
     }

     auto paramBuilder = AuthorizationSetBuilder()
                             .Authorization(TAG_ALGORITHM, Algorithm::RSA)
                             .Authorization(TAG_KEY_SIZE, rsa_key_size)
                             .Authorization(TAG_RSA_PUBLIC_EXPONENT, rsa_exponent)
                             .Authorization(TAG_PURPOSE, KeyPurpose::SIGN)
                             .Authorization(TAG_PADDING, PaddingMode::NONE)
                             .Authorization(TAG_DIGEST, Digest::NONE)
                             .Authorization(TAG_BLOB_USAGE_REQUIREMENTS,
                                     KeyBlobUsageRequirements::STANDALONE)
                             .Authorization(TAG_NO_AUTH_REQUIRED)
                             .Authorization(TAG_MIN_SECONDS_BETWEEN_OPS, ratelimit);

     if (!dev.generateKey(paramBuilder, &key)) {
         return -1;
     }

     if (key_out_size) {
         *key_out_size = key.size();
     }

     if (key_buffer_size < key.size()) {
         return -1;
     }

     std::copy(key.data(), key.data() + key.size(), key_buffer);
     return 0;
 }*/

 int keymaster_sign_object_for_cryptfs_scrypt(const uint8_t* key_blob,
                                              size_t key_blob_size,
                                              uint32_t ratelimit,
                                              const uint8_t* object,
                                              const size_t object_size,
                                              uint8_t** signature_buffer,
                                              size_t* signature_buffer_size,
                                              uint8_t* key_buffer,
                                              uint32_t key_buffer_size,
                                              uint32_t* key_out_size)
 {
     Keymaster dev;
     if (!dev) {
         LOG(ERROR) << "Failed to initiate keymaster session\n";
         return -1;
     }
     if (!key_blob || !object || !signature_buffer || !signature_buffer_size) {
         LOG(ERROR) << __FILE__ << ":" << __LINE__ << ":Invalid argument\n";
         return -1;
     }

     AuthorizationSet outParams;
     std::string key(reinterpret_cast<const char*>(key_blob), key_blob_size);
     std::string input(reinterpret_cast<const char*>(object), object_size);
     std::string output;
     KeymasterOperation op;

     auto paramBuilder = AuthorizationSetBuilder()
                             .Authorization(TAG_PADDING, PaddingMode::NONE)
                             .Authorization(TAG_DIGEST, Digest::NONE);

     while (true) {
         op = dev.begin(KeyPurpose::SIGN, key, paramBuilder, &outParams);
         if (op.errorCode() == ErrorCode::KEY_RATE_LIMIT_EXCEEDED) {
             sleep(ratelimit);
             continue;
         } else if (op.errorCode() == ErrorCode::KEY_REQUIRES_UPGRADE) {
             std::string newKey;
             bool ret = dev.upgradeKey(key, paramBuilder, &newKey);
             if(ret == false) {
                 LOG(ERROR) << "Error upgradeKey: \n";
                 return -1;
             }

             if (key_out_size) {
                 *key_out_size = newKey.size();
             }

             if (key_buffer_size < newKey.size()) {
                 LOG(ERROR) << "key buffer size is too small\n";
                 return -1;
             }

             std::copy(newKey.data(), newKey.data() + newKey.size(), key_buffer);
             key = newKey;
         } else break;
     }

     if (op.errorCode() != ErrorCode::OK) {
         LOG(ERROR) << "Error starting keymaster signature transaction: " << int32_t(op.errorCode()) << "\n";
         return -1;
     }

     if (!op.updateCompletely(input, &output)) {
         LOG(ERROR) << "Error sending data to keymaster signature transaction: "
                    << uint32_t(op.errorCode()) << "\n";
         return -1;
     }

     if (!op.finish(&output)) {
         LOG(ERROR) << "Error finalizing keymaster signature transaction: " << int32_t(op.errorCode()) << "\n";
         return -1;
     }

     *signature_buffer = reinterpret_cast<uint8_t*>(malloc(output.size()));
     if (*signature_buffer == nullptr) {
         LOG(ERROR) << "Error allocation buffer for keymaster signature\n";
         return -1;
     }
     *signature_buffer_size = output.size();
     std::copy(output.data(), output.data() + output.size(), *signature_buffer);
     return 0;
 }
	/*
	* Copyright (C) 2016 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.
	*/

	#include "Keymaster3.h"

	//#include <android-base/logging.h>
	#include <keystore/keymaster_tags.h>
	#include <keystore/authorization_set.h>
	#include <keystore/keystore_hidl_support.h>

	#include <iostream>
	#define ERROR 1
	#define LOG(x) std::cout

	using namespace ::keystore;
	using android::hardware::hidl_string;

	namespace android {
	namespace vold {

	KeymasterOperation::~KeymasterOperation() {
	if (mDevice.get()) mDevice->abort(mOpHandle);
	}

	bool KeymasterOperation::updateCompletely(const std::string& input, std::string* output) {
	if (output)
	output->clear();
	auto it = input.begin();
	uint32_t inputConsumed;

	ErrorCode km_error;
	auto hidlCB = [&] (ErrorCode ret, uint32_t _inputConsumed,
	const hidl_vec<KeyParameter>& /ignored/, const hidl_vec<uint8_t>& _output) {
	km_error = ret;
	if (km_error != ErrorCode::OK) return;
	inputConsumed = _inputConsumed;
	if (output)
	output->append(reinterpret_cast<const char*>(&_output[0]), _output.size());
	};

	while (it != input.end()) {
	size_t toRead = static_cast<size_t>(input.end() - it);
	auto inputBlob = blob2hidlVec(reinterpret_cast<const uint8_t>(&it), toRead);
	auto error = mDevice->update(mOpHandle, hidl_vec<KeyParameter>(), inputBlob, hidlCB);
	if (!error.isOk()) {
	LOG(ERROR) << "update failed: " << error.description() << "\n";
	mDevice = nullptr;
	return false;
	}
	if (km_error != ErrorCode::OK) {
	LOG(ERROR) << "update failed, code " << int32_t(km_error) << "\n";
	mDevice = nullptr;
	return false;
	}
	if (inputConsumed > toRead) {
	LOG(ERROR) << "update reported too much input consumed\n";
	mDevice = nullptr;
	return false;
	}
	it += inputConsumed;
	}
	return true;
	}

	bool KeymasterOperation::finish(std::string* output) {
	ErrorCode km_error;
	auto hidlCb = [&] (ErrorCode ret, const hidl_vec<KeyParameter>& /ignored/,
	const hidl_vec<uint8_t>& _output) {
	km_error = ret;
	if (km_error != ErrorCode::OK) return;
	if (output)
	output->assign(reinterpret_cast<const char*>(&_output[0]), _output.size());
	};
	auto error = mDevice->finish(mOpHandle, hidl_vec<KeyParameter>(), hidl_vec<uint8_t>(),
	hidl_vec<uint8_t>(), hidlCb);
	mDevice = nullptr;
	if (!error.isOk()) {
	LOG(ERROR) << "finish failed: " << error.description() << "\n";
	return false;
	}
	if (km_error != ErrorCode::OK) {
	LOG(ERROR) << "finish failed, code " << int32_t(km_error) << "\n";
	return false;
	}
	return true;
	}

	Keymaster::Keymaster() {
	mDevice = ::android::hardware::keymaster::V3_0::IKeymasterDevice::getService();
	}

	/bool Keymaster::generateKey(const AuthorizationSet& inParams, std::string key) {
	ErrorCode km_error;
	auto hidlCb = [&] (ErrorCode ret, const hidl_vec<uint8_t>& keyBlob,
	const KeyCharacteristics& /ignored /) {
	km_error = ret;
	if (km_error != ErrorCode::OK) return;
	if (key)
	key->assign(reinterpret_cast<const char*>(&keyBlob[0]), keyBlob.size());
	};

	auto error = mDevice->generateKey(inParams.hidl_data(), hidlCb);
	if (!error.isOk()) {
	LOG(ERROR) << "generate_key failed: " << error.description() << "\n";
	return false;
	}
	if (km_error != ErrorCode::OK) {
	LOG(ERROR) << "generate_key failed, code " << int32_t(km_error) << "\n";
	return false;
	}
	return true;
	}*/

	bool Keymaster::deleteKey(const std::string& key) {
	LOG(ERROR) << "NOT deleting key in TWRP\n";
	return false;
	/*auto keyBlob = blob2hidlVec(key);
	auto error = mDevice->deleteKey(keyBlob);
	if (!error.isOk()) {
	LOG(ERROR) << "delete_key failed: " << error.description() << "\n";
	return false;
	}
	if (ErrorCode(error) != ErrorCode::OK) {
	LOG(ERROR) << "delete_key failed, code " << uint32_t(ErrorCode(error)) << "\n";
	return false;
	}
	return true;*/
	}

	bool Keymaster::upgradeKey(const std::string& oldKey, const AuthorizationSet& inParams,
	std::string* newKey) {
	auto oldKeyBlob = blob2hidlVec(oldKey);
	ErrorCode km_error;
	auto hidlCb = [&] (ErrorCode ret, const hidl_vec<uint8_t>& upgradedKeyBlob) {
	km_error = ret;
	if (km_error != ErrorCode::OK) return;
	if (newKey)
	newKey->assign(reinterpret_cast<const char*>(&upgradedKeyBlob[0]),
	upgradedKeyBlob.size());
	};
	auto error = mDevice->upgradeKey(oldKeyBlob, inParams.hidl_data(), hidlCb);
	if (!error.isOk()) {
	LOG(ERROR) << "upgrade_key failed: " << error.description() << "\n";
	return false;
	}
	if (km_error != ErrorCode::OK) {
	LOG(ERROR) << "upgrade_key failed, code " << int32_t(km_error) << "\n";
	return false;
	}
	return true;
	}

	KeymasterOperation Keymaster::begin(KeyPurpose purpose, const std::string& key,
	const AuthorizationSet& inParams,
	AuthorizationSet* outParams) {
	auto keyBlob = blob2hidlVec(key);
	uint64_t mOpHandle;
	ErrorCode km_error;

	auto hidlCb = [&] (ErrorCode ret, const hidl_vec<KeyParameter>& _outParams,
	uint64_t operationHandle) {
	km_error = ret;
	if (km_error != ErrorCode::OK) return;
	if (outParams)
	*outParams = _outParams;
	mOpHandle = operationHandle;
	};

	auto error = mDevice->begin(purpose, keyBlob, inParams.hidl_data(), hidlCb);
	if (!error.isOk()) {
	LOG(ERROR) << "begin failed: " << error.description() << "\n";
	return KeymasterOperation(ErrorCode::UNKNOWN_ERROR);
	}
	if (km_error != ErrorCode::OK) {
	LOG(ERROR) << "begin failed, code " << int32_t(km_error) << "\n";
	return KeymasterOperation(km_error);
	}
	return KeymasterOperation(mDevice, mOpHandle);
	}
	bool Keymaster::isSecure() {
	bool _isSecure = false;
	auto rc = mDevice->getHardwareFeatures(
	[&] (bool isSecure, bool, bool, bool, bool, const hidl_string&, const hidl_string&) {
	_isSecure = isSecure; });
	return rc.isOk() && _isSecure;
	}

	} // namespace vold
	} // namespace android

	using namespace ::android::vold;

	/*
	int keymaster_compatibility_cryptfs_scrypt() {
	Keymaster dev;
	if (!dev) {
	LOG(ERROR) << "Failed to initiate keymaster session\n";
	return -1;
	}
	return dev.isSecure();
	}
	*/

	/*int keymaster_create_key_for_cryptfs_scrypt(uint32_t rsa_key_size,
	uint64_t rsa_exponent,
	uint32_t ratelimit,
	uint8_t* key_buffer,
	uint32_t key_buffer_size,
	uint32_t* key_out_size)
	{
	Keymaster dev;
	std::string key;
	if (!dev) {
	LOG(ERROR) << "Failed to initiate keymaster session\n";
	return -1;
	}
	if (!key_buffer \|\| !key_out_size) {
	LOG(ERROR) << __FILE__ << ":" << __LINE__ << ":Invalid argument\n";
	return -1;
	}
	if (key_out_size) {
	*key_out_size = 0;
	}

	auto paramBuilder = AuthorizationSetBuilder()
	.Authorization(TAG_ALGORITHM, Algorithm::RSA)
	.Authorization(TAG_KEY_SIZE, rsa_key_size)
	.Authorization(TAG_RSA_PUBLIC_EXPONENT, rsa_exponent)
	.Authorization(TAG_PURPOSE, KeyPurpose::SIGN)
	.Authorization(TAG_PADDING, PaddingMode::NONE)
	.Authorization(TAG_DIGEST, Digest::NONE)
	.Authorization(TAG_BLOB_USAGE_REQUIREMENTS,
	KeyBlobUsageRequirements::STANDALONE)
	.Authorization(TAG_NO_AUTH_REQUIRED)
	.Authorization(TAG_MIN_SECONDS_BETWEEN_OPS, ratelimit);

	if (!dev.generateKey(paramBuilder, &key)) {
	return -1;
	}

	if (key_out_size) {
	*key_out_size = key.size();
	}

	if (key_buffer_size < key.size()) {
	return -1;
	}

	std::copy(key.data(), key.data() + key.size(), key_buffer);
	return 0;
	}*/

	int keymaster_sign_object_for_cryptfs_scrypt(const uint8_t* key_blob,
	size_t key_blob_size,
	uint32_t ratelimit,
	const uint8_t* object,
	const size_t object_size,
	uint8_t** signature_buffer,
	size_t* signature_buffer_size,
	uint8_t* key_buffer,
	uint32_t key_buffer_size,
	uint32_t* key_out_size)
	{
	Keymaster dev;
	if (!dev) {
	LOG(ERROR) << "Failed to initiate keymaster session\n";
	return -1;
	}
	if (!key_blob \|\| !object \|\| !signature_buffer \|\| !signature_buffer_size) {
	LOG(ERROR) << __FILE__ << ":" << __LINE__ << ":Invalid argument\n";
	return -1;
	}

	AuthorizationSet outParams;
	std::string key(reinterpret_cast<const char*>(key_blob), key_blob_size);
	std::string input(reinterpret_cast<const char*>(object), object_size);
	std::string output;
	KeymasterOperation op;

	auto paramBuilder = AuthorizationSetBuilder()
	.Authorization(TAG_PADDING, PaddingMode::NONE)
	.Authorization(TAG_DIGEST, Digest::NONE);

	while (true) {
	op = dev.begin(KeyPurpose::SIGN, key, paramBuilder, &outParams);
	if (op.errorCode() == ErrorCode::KEY_RATE_LIMIT_EXCEEDED) {
	sleep(ratelimit);
	continue;
	} else if (op.errorCode() == ErrorCode::KEY_REQUIRES_UPGRADE) {
	std::string newKey;
	bool ret = dev.upgradeKey(key, paramBuilder, &newKey);
	if(ret == false) {
	LOG(ERROR) << "Error upgradeKey: \n";
	return -1;
	}

	if (key_out_size) {
	*key_out_size = newKey.size();
	}

	if (key_buffer_size < newKey.size()) {
	LOG(ERROR) << "key buffer size is too small\n";
	return -1;
	}

	std::copy(newKey.data(), newKey.data() + newKey.size(), key_buffer);
	key = newKey;
	} else break;
	}

	if (op.errorCode() != ErrorCode::OK) {
	LOG(ERROR) << "Error starting keymaster signature transaction: " << int32_t(op.errorCode()) << "\n";
	return -1;
	}

	if (!op.updateCompletely(input, &output)) {
	LOG(ERROR) << "Error sending data to keymaster signature transaction: "
	<< uint32_t(op.errorCode()) << "\n";
	return -1;
	}

	if (!op.finish(&output)) {
	LOG(ERROR) << "Error finalizing keymaster signature transaction: " << int32_t(op.errorCode()) << "\n";
	return -1;
	}

	signature_buffer = reinterpret_cast<uint8_t>(malloc(output.size()));
	if (*signature_buffer == nullptr) {
	LOG(ERROR) << "Error allocation buffer for keymaster signature\n";
	return -1;
	}
	*signature_buffer_size = output.size();
	std::copy(output.data(), output.data() + output.size(), *signature_buffer);
	return 0;
	}