content: /*
   * Copyright (c) 2012, 2022, Oracle and/or its affiliates.
   *
   * This program is free software; you can redistribute it and/or modify it under
   * the terms of the GNU General Public License, version 2.0, as published by the
   * Free Software Foundation.
   *
   * This program is also distributed with certain software (including but not
   * limited to OpenSSL) that is licensed under separate terms, as designated in a
   * particular file or component or in included license documentation. The
   * authors of MySQL hereby grant you an additional permission to link the
   * program and your derivative works with the separately licensed software that
   * they have included with MySQL.
   *
   * Without limiting anything contained in the foregoing, this file, which is
   * part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
   * version 1.0, a copy of which can be found at
   * http://oss.oracle.com/licenses/universal-foss-exception.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
   * FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
   * for more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
   */
  
  package com.mysql.cj.protocol.a.authentication;
  
  import java.util.List;
  
  import com.mysql.cj.callback.MysqlCallbackHandler;
  import com.mysql.cj.callback.UsernameCallback;
  import com.mysql.cj.protocol.AuthenticationPlugin;
  import com.mysql.cj.protocol.Protocol;
  import com.mysql.cj.protocol.Security;
  import com.mysql.cj.protocol.a.NativeConstants.StringSelfDataType;
  import com.mysql.cj.protocol.a.NativePacketPayload;
  
  /**
   * MySQL Native Password Authentication Plugin
   */
  public class MysqlNativePasswordPlugin implements AuthenticationPlugin<NativePacketPayload> {
      public static String PLUGIN_NAME = "mysql_native_password";
  
      private Protocol<NativePacketPayload> protocol = null;
      private MysqlCallbackHandler usernameCallbackHandler = null;
      private String password = null;
  
      @Override
      public void init(Protocol<NativePacketPayload> prot, MysqlCallbackHandler cbh) {
          this.protocol = prot;
          this.usernameCallbackHandler = cbh;
      }
  
      public void destroy() {
          reset();
          this.protocol = null;
          this.usernameCallbackHandler = null;
          this.password = null;
      }
  
      public String getProtocolPluginName() {
          return PLUGIN_NAME;
      }
  
      public boolean requiresConfidentiality() {
          return false;
      }
  
      public boolean isReusable() {
          return true;
      }
  
      public void setAuthenticationParameters(String user, String password) {
          this.password = password;
          if (user == null && this.usernameCallbackHandler != null) {
              // Fall back to system login user.
              this.usernameCallbackHandler.handle(new UsernameCallback(System.getProperty("user.name")));
          }
      }
  
      public boolean nextAuthenticationStep(NativePacketPayload fromServer, List<NativePacketPayload> toServer) {
          toServer.clear();
  
          NativePacketPayload packet = null;
  
          String pwd = this.password;
  
          if (fromServer == null || pwd == null || pwd.length() == 0) {
              packet = new NativePacketPayload(new byte[0]);
          } else {
              packet = new NativePacketPayload(Security.scramble411(pwd, fromServer.readBytes(StringSelfDataType.STRING_TERM),
                      this.protocol.getServerSession().getCharsetSettings().getPasswordCharacterEncoding()));
          }
          toServer.add(packet);
  
          return true;
      }
  }
  