content: /*
   * Copyright (c) 2017, 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.security.DigestException;
  import java.util.List;
  
  import com.mysql.cj.Messages;
  import com.mysql.cj.conf.PropertyKey;
  import com.mysql.cj.exceptions.CJException;
  import com.mysql.cj.exceptions.ExceptionFactory;
  import com.mysql.cj.exceptions.UnableToConnectException;
  import com.mysql.cj.protocol.Protocol;
  import com.mysql.cj.protocol.Security;
  import com.mysql.cj.protocol.a.NativeConstants;
  import com.mysql.cj.protocol.a.NativeConstants.IntegerDataType;
  import com.mysql.cj.protocol.a.NativeConstants.StringLengthDataType;
  import com.mysql.cj.protocol.a.NativeConstants.StringSelfDataType;
  import com.mysql.cj.protocol.a.NativePacketPayload;
  import com.mysql.cj.util.StringUtils;
  
  public class CachingSha2PasswordPlugin extends Sha256PasswordPlugin {
      public static String PLUGIN_NAME = "caching_sha2_password";
  
      public enum AuthStage {
          FAST_AUTH_SEND_SCRAMBLE, FAST_AUTH_READ_RESULT, FAST_AUTH_COMPLETE, FULL_AUTH;
      }
  
      private AuthStage stage = AuthStage.FAST_AUTH_SEND_SCRAMBLE;
  
      @Override
      public void init(Protocol<NativePacketPayload> prot) {
          super.init(prot);
          this.stage = AuthStage.FAST_AUTH_SEND_SCRAMBLE;
      }
  
      @Override
      public void reset() {
          this.stage = AuthStage.FAST_AUTH_SEND_SCRAMBLE;
      }
  
      @Override
      public void destroy() {
          super.destroy();
          this.stage = AuthStage.FAST_AUTH_SEND_SCRAMBLE;
      }
  
      @Override
      public String getProtocolPluginName() {
          return PLUGIN_NAME;
      }
  
      @Override
      public boolean nextAuthenticationStep(NativePacketPayload fromServer, List<NativePacketPayload> toServer) {
          toServer.clear();
  
          if (this.password == null || this.password.length() == 0 || fromServer == null) {
              // no password
              NativePacketPayload packet = new NativePacketPayload(new byte[] { 0 });
              toServer.add(packet);
  
          } else {
              try {
                  if (this.stage == AuthStage.FAST_AUTH_SEND_SCRAMBLE) {
                      // send a scramble for fast auth
                      this.seed = fromServer.readString(StringSelfDataType.STRING_TERM, null);
                      toServer.add(new NativePacketPayload(Security.scrambleCachingSha2(
                              StringUtils.getBytes(this.password, this.protocol.getServerSession().getCharsetSettings().getPasswordCharacterEncoding()),
                              this.seed.getBytes())));
                      this.stage = AuthStage.FAST_AUTH_READ_RESULT;
                      return true;
  
                  } else if (this.stage == AuthStage.FAST_AUTH_READ_RESULT) {
                      int fastAuthResult = fromServer.readBytes(StringLengthDataType.STRING_FIXED, 1)[0];
                      switch (fastAuthResult) {
                          case 3:
                              this.stage = AuthStage.FAST_AUTH_COMPLETE;
                              return true;
                          case 4:
                              this.stage = AuthStage.FULL_AUTH;
                              break;
                          default:
                              throw ExceptionFactory.createException("Unknown server response after fast auth.", this.protocol.getExceptionInterceptor());
                      }
                  }
  
                  if (this.protocol.getSocketConnection().isSSLEstablished()) {
                      // allow plain text over SSL
                      NativePacketPayload packet = new NativePacketPayload(
                              StringUtils.getBytes(this.password, this.protocol.getServerSession().getCharsetSettings().getPasswordCharacterEncoding()));
                      packet.setPosition(packet.getPayloadLength());
                      packet.writeInteger(IntegerDataType.INT1, 0);
                      packet.setPosition(0);
                      toServer.add(packet);
  
                  } else if (this.serverRSAPublicKeyFile.getValue() != null) {
                      // encrypt with given key, don't use "Public Key Retrieval"
                      NativePacketPayload packet = new NativePacketPayload(encryptPassword());
                      toServer.add(packet);
  
                  } else {
                      if (!this.protocol.getPropertySet().getBooleanProperty(PropertyKey.allowPublicKeyRetrieval).getValue()) {
                          throw ExceptionFactory.createException(UnableToConnectException.class, Messages.getString("Sha256PasswordPlugin.2"),
                                  this.protocol.getExceptionInterceptor());
  
                      }
  
                      // We must request the public key from the server to encrypt the password
                      if (this.publicKeyRequested && fromServer.getPayloadLength() > NativeConstants.SEED_LENGTH + 1) { // auth data is null terminated
                          // Servers affected by Bug#70865 could send Auth Switch instead of key after Public Key Retrieval,
                          // so we check payload length to detect that.
  
                          // read key response
                          this.publicKeyString = fromServer.readString(StringSelfDataType.STRING_TERM, null);
                          NativePacketPayload packet = new NativePacketPayload(encryptPassword());
                          toServer.add(packet);
                          this.publicKeyRequested = false;
                      } else {
                          // build and send Public Key Retrieval packet
                          NativePacketPayload packet = new NativePacketPayload(new byte[] { 2 }); // was 1 in sha256_password
                          toServer.add(packet);
                          this.publicKeyRequested = true;
                      }
                  }
              } catch (CJException | DigestException e) {
                  throw ExceptionFactory.createException(e.getMessage(), e, this.protocol.getExceptionInterceptor());
              }
          }
          return true;
      }
  
      @Override
      protected byte[] encryptPassword() {
          if (this.protocol.versionMeetsMinimum(8, 0, 5)) {
              return super.encryptPassword();
          }
          return super.encryptPassword("RSA/ECB/PKCS1Padding");
      }
  }
  