content: /*************************** The CRY.ME project (2023) *************************************************
   *
   *  This file is part of the CRY.ME project (https://github.com/ANSSI-FR/cry-me).
   *  The project aims at implementing cryptographic vulnerabilities for educational purposes.
   *  Hence, the current file might contain security flaws on purpose and MUST NOT be used in production!
   *  Please do not use this source code outside this scope, or use it knowingly.
   *
   *  Many files come from the Android element (https://github.com/vector-im/element-android), the
   *  Matrix SDK (https://github.com/matrix-org/matrix-android-sdk2) as well as the Android Yubikit
   *  (https://github.com/Yubico/yubikit-android) projects and have been willingly modified
   *  for the CRY.ME project purposes. The Android element, Matrix SDK and Yubikit projects are distributed
   *  under the Apache-2.0 license, and so is the CRY.ME project.
   *
   ***************************  (END OF CRY.ME HEADER)   *************************************************/
  
  /*
   * Copyright 2016 OpenMarket Ltd
   * Copyright 2016 Vector Creations Ltd
   *
   * 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.
   */
  
  package org.matrix.olm;
  
  import android.util.Log;
  
  import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.io.ObjectOutputStream;
  
  /**
   * Helper class dedicated to serialization mechanism (template method pattern).
   */
  abstract class CommonSerializeUtils {
      private static final String LOG_TAG = "CommonSerializeUtils";
  
      /**
       * Kick off the serialization mechanism.
       * @param aOutStream output stream for serializing
       * @throws IOException exception
       */
      protected void serialize(ObjectOutputStream aOutStream) throws IOException {
          aOutStream.defaultWriteObject();
  
          // generate serialization key
          byte[] key = OlmUtility.getRandomKey();
  
          // compute pickle string
          StringBuffer errorMsg = new StringBuffer();
          byte[] pickledData = serialize(key, errorMsg);
  
          if(null == pickledData) {
              throw new OlmException(OlmException.EXCEPTION_CODE_ACCOUNT_SERIALIZATION, String.valueOf(errorMsg));
          } else {
              aOutStream.writeObject(new String(key, "UTF-8"));
              aOutStream.writeObject(new String(pickledData, "UTF-8"));
          }
      }
  
      /**
       * Kick off the deserialization mechanism.
       * @param aInStream input stream
       * @throws Exception the exception
       */
      protected void deserialize(ObjectInputStream aInStream) throws Exception {
          aInStream.defaultReadObject();
  
          String keyAsString = (String)aInStream.readObject();
          String pickledDataAsString = (String)aInStream.readObject();
  
          byte[] key;
          byte[] pickledData;
  
          try {
              key = keyAsString.getBytes("UTF-8");
              pickledData = pickledDataAsString.getBytes("UTF-8");
  
              deserialize(pickledData, key);
          } catch (Exception e) {
              throw new OlmException(OlmException.EXCEPTION_CODE_ACCOUNT_DESERIALIZATION, e.getMessage());
          }
  
          Log.d(LOG_TAG,"## deserializeObject(): success");
      }
  
      protected abstract byte[] serialize(byte[] aKey, StringBuffer aErrorMsg);
      protected abstract void deserialize(byte[] aSerializedData, byte[] aKey) throws Exception;
  }
  