content: /*
   * Copyright 1999-2012 Alibaba Group.
   *  
   * 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 com.alibaba.cobar.heartbeat;
  
  import com.alibaba.cobar.mysql.CharsetUtil;
  import com.alibaba.cobar.mysql.SecurityUtil;
  import com.alibaba.cobar.net.NIOHandler;
  import com.alibaba.cobar.net.mysql.EOFPacket;
  import com.alibaba.cobar.net.mysql.ErrorPacket;
  import com.alibaba.cobar.net.mysql.HandshakePacket;
  import com.alibaba.cobar.net.mysql.OkPacket;
  import com.alibaba.cobar.net.mysql.Reply323Packet;
  
  /**
   * @author xianmao.hexm
   */
  public class MySQLDetectorAuthenticator implements NIOHandler {
  
      private final MySQLDetector source;
  
      public MySQLDetectorAuthenticator(MySQLDetector source) {
          this.source = source;
      }
  
      @Override
      public void handle(byte[] data) {
          MySQLDetector source = this.source;
          HandshakePacket hsp = source.getHandshake();
          if (hsp == null) {
              // 设置握手数据包
              hsp = new HandshakePacket();
              hsp.read(data);
              source.setHandshake(hsp);
  
              // 设置字符集编码
              int charsetIndex = (hsp.serverCharsetIndex & 0xff);
              String charset = CharsetUtil.getDbCharset(charsetIndex);
              if (charset != null) {
                  source.setCharsetIndex(charsetIndex);
              } else {
                  throw new RuntimeException("Unknown charsetIndex:" + charsetIndex);
              }
  
              // 发送认证数据包
              source.authenticate();
          } else {
              switch (data[4]) {
              case OkPacket.FIELD_COUNT:
                  source.setHandler(new MySQLDetectorHandler(source));
                  source.setAuthenticated(true);
                  source.heartbeat();// 成功后发起心跳。
                  break;
              case ErrorPacket.FIELD_COUNT:
                  ErrorPacket err = new ErrorPacket();
                  err.read(data);
                  throw new RuntimeException(new String(err.message));
              case EOFPacket.FIELD_COUNT:
                  auth323(data[3], hsp.seed);
                  break;
              default:
                  throw new RuntimeException("Unknown packet");
              }
          }
      }
  
      /**
       * 发送323响应认证数据包
       */
      private void auth323(byte packetId, byte[] seed) {
          Reply323Packet r323 = new Reply323Packet();
          r323.packetId = ++packetId;
          String pass = source.getPassword();
          if (pass != null && pass.length() > 0) {
              r323.seed = SecurityUtil.scramble323(pass, new String(seed)).getBytes();
          }
          r323.write(source);
      }
  
  }
  