text: /*
   * 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 "Keymaster.h"
  
  #include <android-base/logging.h>
  #include <hardware/hardware.h>
  #include <hardware/keymaster1.h>
  #include <hardware/keymaster2.h>
  
  namespace android {
  namespace vold {
  
  class IKeymasterDevice {
    public:
      IKeymasterDevice() {}
      virtual ~IKeymasterDevice() {}
      virtual keymaster_error_t generate_key(const keymaster_key_param_set_t* params,
                                             keymaster_key_blob_t* key_blob) const = 0;
      virtual keymaster_error_t delete_key(const keymaster_key_blob_t* key) const = 0;
      virtual keymaster_error_t begin(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) const = 0;
      virtual keymaster_error_t update(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) const = 0;
      virtual keymaster_error_t finish(keymaster_operation_handle_t operation_handle,
                                       const keymaster_key_param_set_t* in_params,
                                       const keymaster_blob_t* signature,
                                       keymaster_key_param_set_t* out_params,
                                       keymaster_blob_t* output) const = 0;
      virtual keymaster_error_t abort(keymaster_operation_handle_t operation_handle) const = 0;
  
    protected:
      DISALLOW_COPY_AND_ASSIGN(IKeymasterDevice);
  };
  
  template <typename T> class KeymasterDevice : public IKeymasterDevice {
    public:
      KeymasterDevice(T* d) : mDevice{d} {}
      keymaster_error_t generate_key(const keymaster_key_param_set_t* params,
                                     keymaster_key_blob_t* key_blob) const override final {
          return mDevice->generate_key(mDevice, params, key_blob, nullptr);
      }
      keymaster_error_t delete_key(const keymaster_key_blob_t* key) const override final {
          if (mDevice->delete_key == nullptr) return KM_ERROR_OK;
          return mDevice->delete_key(mDevice, key);
      }
      keymaster_error_t begin(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) const override final {
          return mDevice->begin(mDevice, purpose, key, in_params, out_params, operation_handle);
      }
      keymaster_error_t update(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) const override final {
          return mDevice->update(mDevice, operation_handle, in_params, input, input_consumed,
                                 out_params, output);
      }
      keymaster_error_t abort(keymaster_operation_handle_t operation_handle) const override final {
          return mDevice->abort(mDevice, operation_handle);
      }
  
    protected:
      T* const mDevice;
  };
  
  class Keymaster1Device : public KeymasterDevice<keymaster1_device_t> {
    public:
      Keymaster1Device(keymaster1_device_t* d) : KeymasterDevice<keymaster1_device_t>{d} {}
      ~Keymaster1Device() override final { keymaster1_close(mDevice); }
      keymaster_error_t finish(keymaster_operation_handle_t operation_handle,
                               const keymaster_key_param_set_t* in_params,
                               const keymaster_blob_t* signature,
                               keymaster_key_param_set_t* out_params,
                               keymaster_blob_t* output) const override final {
          return mDevice->finish(mDevice, operation_handle, in_params, signature, out_params, output);
      }
  };
  
  class Keymaster2Device : public KeymasterDevice<keymaster2_device_t> {
    public:
      Keymaster2Device(keymaster2_device_t* d) : KeymasterDevice<keymaster2_device_t>{d} {}
      ~Keymaster2Device() override final { keymaster2_close(mDevice); }
      keymaster_error_t finish(keymaster_operation_handle_t operation_handle,
                               const keymaster_key_param_set_t* in_params,
                               const keymaster_blob_t* signature,
                               keymaster_key_param_set_t* out_params,
                               keymaster_blob_t* output) const override final {
          return mDevice->finish(mDevice, operation_handle, in_params, nullptr, signature, out_params,
                                 output);
      }
  };
  
  KeymasterOperation::~KeymasterOperation() {
      if (mDevice) mDevice->abort(mOpHandle);
  }
  
  bool KeymasterOperation::updateCompletely(const std::string& input, std::string* output) {
      output->clear();
      auto it = input.begin();
      while (it != input.end()) {
          size_t toRead = static_cast<size_t>(input.end() - it);
          keymaster_blob_t inputBlob{reinterpret_cast<const uint8_t*>(&*it), toRead};
          keymaster_blob_t outputBlob;
          size_t inputConsumed;
          auto error =
              mDevice->update(mOpHandle, nullptr, &inputBlob, &inputConsumed, nullptr, &outputBlob);
          if (error != KM_ERROR_OK) {
              LOG(ERROR) << "update failed, code " << error;
              mDevice = nullptr;
              return false;
          }
          output->append(reinterpret_cast<const char*>(outputBlob.data), outputBlob.data_length);
          free(const_cast<uint8_t*>(outputBlob.data));
          if (inputConsumed > toRead) {
              LOG(ERROR) << "update reported too much input consumed";
              mDevice = nullptr;
              return false;
          }
          it += inputConsumed;
      }
      return true;
  }
  
  bool KeymasterOperation::finish() {
      auto error = mDevice->finish(mOpHandle, nullptr, nullptr, nullptr, nullptr);
      mDevice = nullptr;
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "finish failed, code " << error;
          return false;
      }
      return true;
  }
  
  bool KeymasterOperation::finishWithOutput(std::string* output) {
      keymaster_blob_t outputBlob;
      auto error = mDevice->finish(mOpHandle, nullptr, nullptr, nullptr, &outputBlob);
      mDevice = nullptr;
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "finish failed, code " << error;
          return false;
      }
      output->assign(reinterpret_cast<const char*>(outputBlob.data), outputBlob.data_length);
      free(const_cast<uint8_t*>(outputBlob.data));
      return true;
  }
  
  Keymaster::Keymaster() {
      mDevice = nullptr;
      const hw_module_t* module;
      int ret = hw_get_module_by_class(KEYSTORE_HARDWARE_MODULE_ID, NULL, &module);
      if (ret != 0) {
          LOG(ERROR) << "hw_get_module_by_class returned " << ret;
          return;
      }
      if (module->module_api_version == KEYMASTER_MODULE_API_VERSION_1_0) {
          keymaster1_device_t* device;
          ret = keymaster1_open(module, &device);
          if (ret != 0) {
              LOG(ERROR) << "keymaster1_open returned " << ret;
              return;
          }
          mDevice = std::make_shared<Keymaster1Device>(device);
      } else if (module->module_api_version == KEYMASTER_MODULE_API_VERSION_2_0) {
          keymaster2_device_t* device;
          ret = keymaster2_open(module, &device);
          if (ret != 0) {
              LOG(ERROR) << "keymaster2_open returned " << ret;
              return;
          }
          mDevice = std::make_shared<Keymaster2Device>(device);
      } else {
          LOG(ERROR) << "module_api_version is " << module->module_api_version;
          return;
      }
  }
  
  bool Keymaster::generateKey(const keymaster::AuthorizationSet& inParams, std::string* key) {
      keymaster_key_blob_t keyBlob;
      auto error = mDevice->generate_key(&inParams, &keyBlob);
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "generate_key failed, code " << error;
          return false;
      }
      key->assign(reinterpret_cast<const char*>(keyBlob.key_material), keyBlob.key_material_size);
      free(const_cast<uint8_t*>(keyBlob.key_material));
      return true;
  }
  
  bool Keymaster::deleteKey(const std::string& key) {
      keymaster_key_blob_t keyBlob{reinterpret_cast<const uint8_t*>(key.data()), key.size()};
      auto error = mDevice->delete_key(&keyBlob);
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "delete_key failed, code " << error;
          return false;
      }
      return true;
  }
  
  KeymasterOperation Keymaster::begin(keymaster_purpose_t purpose, const std::string& key,
                                      const keymaster::AuthorizationSet& inParams,
                                      keymaster::AuthorizationSet* outParams) {
      keymaster_key_blob_t keyBlob{reinterpret_cast<const uint8_t*>(key.data()), key.size()};
      keymaster_operation_handle_t mOpHandle;
      keymaster_key_param_set_t outParams_set;
      auto error = mDevice->begin(purpose, &keyBlob, &inParams, &outParams_set, &mOpHandle);
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "begin failed, code " << error;
          return KeymasterOperation(nullptr, mOpHandle);
      }
      outParams->Clear();
      outParams->push_back(outParams_set);
      keymaster_free_param_set(&outParams_set);
      return KeymasterOperation(mDevice, mOpHandle);
  }
  
  KeymasterOperation Keymaster::begin(keymaster_purpose_t purpose, const std::string& key,
                                      const keymaster::AuthorizationSet& inParams) {
      keymaster_key_blob_t keyBlob{reinterpret_cast<const uint8_t*>(key.data()), key.size()};
      keymaster_operation_handle_t mOpHandle;
      auto error = mDevice->begin(purpose, &keyBlob, &inParams, nullptr, &mOpHandle);
      if (error != KM_ERROR_OK) {
          LOG(ERROR) << "begin failed, code " << error;
          return KeymasterOperation(nullptr, mOpHandle);
      }
      return KeymasterOperation(mDevice, mOpHandle);
  }
  
  }  // namespace vold
  }  // namespace android
  