gt:                 if (kd == null) {       // unlikely
context: /*
   * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code 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 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package sun.security.ssl;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.security.GeneralSecurityException;
  import java.security.PrivateKey;
  import java.security.PublicKey;
  import java.text.MessageFormat;
  import java.util.Locale;
  import javax.crypto.SecretKey;
  import sun.security.ssl.RSAKeyExchange.EphemeralRSACredentials;
  import sun.security.ssl.RSAKeyExchange.EphemeralRSAPossession;
  import sun.security.ssl.RSAKeyExchange.RSAPremasterSecret;
  import sun.security.ssl.SSLHandshake.HandshakeMessage;
  import sun.security.ssl.X509Authentication.X509Credentials;
  import sun.security.ssl.X509Authentication.X509Possession;
  import sun.misc.HexDumpEncoder;
  
  /**
   * Pack of the "ClientKeyExchange" handshake message.
   */
  final class RSAClientKeyExchange {
      static final SSLConsumer rsaHandshakeConsumer =
          new RSAClientKeyExchangeConsumer();
      static final HandshakeProducer rsaHandshakeProducer =
          new RSAClientKeyExchangeProducer();
  
      /**
       * The RSA ClientKeyExchange handshake message.
       */
      private static final
              class RSAClientKeyExchangeMessage extends HandshakeMessage {
          final int protocolVersion;
          final boolean useTLS10PlusSpec;
          final byte[] encrypted;
  
          RSAClientKeyExchangeMessage(HandshakeContext context,
                  RSAPremasterSecret premaster,
                  PublicKey publicKey) throws GeneralSecurityException {
              super(context);
              this.protocolVersion = context.clientHelloVersion;
              this.encrypted = premaster.getEncoded(
                      publicKey, context.sslContext.getSecureRandom());
              this.useTLS10PlusSpec = ProtocolVersion.useTLS10PlusSpec(
                      protocolVersion);
          }
  
          RSAClientKeyExchangeMessage(HandshakeContext context,
                  ByteBuffer m) throws IOException {
              super(context);
  
              if (m.remaining() < 2) {
                  throw context.conContext.fatal(Alert.HANDSHAKE_FAILURE,
                      "Invalid RSA ClientKeyExchange message: insufficient data");
              }
  
              this.protocolVersion = context.clientHelloVersion;
              this.useTLS10PlusSpec = ProtocolVersion.useTLS10PlusSpec(
                      protocolVersion);
              if (useTLS10PlusSpec) {
                  this.encrypted = Record.getBytes16(m);
              } else {    //  SSL 3.0
                  this.encrypted = new byte[m.remaining()];
                  m.get(encrypted);
              }
          }
  
          @Override
          public SSLHandshake handshakeType() {
              return SSLHandshake.CLIENT_KEY_EXCHANGE;
          }
  
          @Override
          public int messageLength() {
              if (useTLS10PlusSpec) {
                  return encrypted.length + 2;
              } else {
                  return encrypted.length;
              }
          }
  
          @Override
          public void send(HandshakeOutStream hos) throws IOException {
              if (useTLS10PlusSpec) {
                  hos.putBytes16(encrypted);
              } else {
                  hos.write(encrypted);
              }
          }
  
          @Override
          public String toString() {
              MessageFormat messageFormat = new MessageFormat(
                  "\"RSA ClientKeyExchange\": '{'\n" +
                  "  \"client_version\":  {0}\n" +
                  "  \"encncrypted\": '{'\n" +
                  "{1}\n" +
                  "  '}'\n" +
                  "'}'",
                  Locale.ENGLISH);
  
              HexDumpEncoder hexEncoder = new HexDumpEncoder();
              Object[] messageFields = {
                  ProtocolVersion.nameOf(protocolVersion),
                  Utilities.indent(
                          hexEncoder.encodeBuffer(encrypted), "    "),
              };
              return messageFormat.format(messageFields);
          }
      }
  
      /**
       * The RSA "ClientKeyExchange" handshake message producer.
       */
      private static final
              class RSAClientKeyExchangeProducer implements HandshakeProducer {
          // Prevent instantiation of this class.
          private RSAClientKeyExchangeProducer() {
              // blank
          }
  
          @Override
          public byte[] produce(ConnectionContext context,
                  HandshakeMessage message) throws IOException {
              // This happens in client side only.
              ClientHandshakeContext chc = (ClientHandshakeContext)context;
  
              EphemeralRSACredentials rsaCredentials = null;
              X509Credentials x509Credentials = null;
              for (SSLCredentials credential : chc.handshakeCredentials) {
                  if (credential instanceof EphemeralRSACredentials) {
                      rsaCredentials = (EphemeralRSACredentials)credential;
                      if (x509Credentials != null) {
                          break;
                      }
                  } else if (credential instanceof X509Credentials) {
                      x509Credentials = (X509Credentials)credential;
                      if (rsaCredentials != null) {
                          break;
                      }
                  }
              }
  
              if (rsaCredentials == null && x509Credentials == null) {
                  throw chc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                      "No RSA credentials negotiated for client key exchange");
              }
  
              PublicKey publicKey = (rsaCredentials != null) ?
                      rsaCredentials.popPublicKey : x509Credentials.popPublicKey;
              if (!publicKey.getAlgorithm().equals("RSA")) {      // unlikely
                  throw chc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                      "Not RSA public key for client key exchange");
              }
  
              RSAPremasterSecret premaster;
              RSAClientKeyExchangeMessage ckem;
              try {
                  premaster = RSAPremasterSecret.createPremasterSecret(chc);
                  chc.handshakePossessions.add(premaster);
                  ckem = new RSAClientKeyExchangeMessage(
                          chc, premaster, publicKey);
              } catch (GeneralSecurityException gse) {
                  throw chc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                          "Cannot generate RSA premaster secret", gse);
              }
              if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
                  SSLLogger.fine(
                      "Produced RSA ClientKeyExchange handshake message", ckem);
              }
  
              // Output the handshake message.
              ckem.write(chc.handshakeOutput);
              chc.handshakeOutput.flush();
  
              // update the states
              SSLKeyExchange ke = SSLKeyExchange.valueOf(
                      chc.negotiatedCipherSuite.keyExchange,
                      chc.negotiatedProtocol);
              if (ke == null) {   // unlikely
                  throw chc.conContext.fatal(Alert.INTERNAL_ERROR,
                          "Not supported key exchange type");
              } else {
                  SSLKeyDerivation masterKD = ke.createKeyDerivation(chc);
                  SecretKey masterSecret =
                          masterKD.deriveKey("MasterSecret", null);
  
                  // update the states
                  chc.handshakeSession.setMasterSecret(masterSecret);
                  SSLTrafficKeyDerivation kd =
                          SSLTrafficKeyDerivation.valueOf(chc.negotiatedProtocol);
                  if (kd == null) {   // unlikely
                      throw chc.conContext.fatal(Alert.INTERNAL_ERROR,
                              "Not supported key derivation: " +
                              chc.negotiatedProtocol);
                  } else {
                      chc.handshakeKeyDerivation =
                          kd.createKeyDerivation(chc, masterSecret);
                  }
              }
  
              // The handshake message has been delivered.
              return null;
          }
      }
  
      /**
       * The RSA "ClientKeyExchange" handshake message consumer.
       */
      private static final
              class RSAClientKeyExchangeConsumer implements SSLConsumer {
          // Prevent instantiation of this class.
          private RSAClientKeyExchangeConsumer() {
              // blank
          }
  
          @Override
          public void consume(ConnectionContext context,
                  ByteBuffer message) throws IOException {
              // The consuming happens in server side only.
              ServerHandshakeContext shc = (ServerHandshakeContext)context;
  
              EphemeralRSAPossession rsaPossession = null;
              X509Possession x509Possession = null;
              for (SSLPossession possession : shc.handshakePossessions) {
                  if (possession instanceof EphemeralRSAPossession) {
                      rsaPossession = (EphemeralRSAPossession)possession;
                      break;
                  } else if (possession instanceof X509Possession) {
                      x509Possession = (X509Possession)possession;
                      if (rsaPossession != null) {
                          break;
                      }
                  }
              }
  
              if (rsaPossession == null && x509Possession == null) {  // unlikely
                  throw shc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                      "No RSA possessions negotiated for client key exchange");
              }
  
              PrivateKey privateKey = (rsaPossession != null) ?
                      rsaPossession.popPrivateKey : x509Possession.popPrivateKey;
              if (!privateKey.getAlgorithm().equals("RSA")) {     // unlikely
                  throw shc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                      "Not RSA private key for client key exchange");
              }
  
              RSAClientKeyExchangeMessage ckem =
                      new RSAClientKeyExchangeMessage(shc, message);
              if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {
                  SSLLogger.fine(
                      "Consuming RSA ClientKeyExchange handshake message", ckem);
              }
  
              // create the credentials
              RSAPremasterSecret premaster;
              try {
                  premaster =
                      RSAPremasterSecret.decode(shc, privateKey, ckem.encrypted);
                  shc.handshakeCredentials.add(premaster);
              } catch (GeneralSecurityException gse) {
                  throw shc.conContext.fatal(Alert.ILLEGAL_PARAMETER,
                      "Cannot decode RSA premaster secret", gse);
              }
  
              // update the states
              SSLKeyExchange ke = SSLKeyExchange.valueOf(
                      shc.negotiatedCipherSuite.keyExchange,
                      shc.negotiatedProtocol);
              if (ke == null) {   // unlikely
                  throw shc.conContext.fatal(Alert.INTERNAL_ERROR,
                          "Not supported key exchange type");
              } else {
                  SSLKeyDerivation masterKD = ke.createKeyDerivation(shc);
                  SecretKey masterSecret =
                          masterKD.deriveKey("MasterSecret", null);
  
                  // update the states
                  shc.handshakeSession.setMasterSecret(masterSecret);
                  SSLTrafficKeyDerivation kd =
                          SSLTrafficKeyDerivation.valueOf(shc.negotiatedProtocol);
  