//***************************************************************************
// (c) Copyright IBM Corp. 2007 All rights reserved.
// 
// The following sample of source code ("Sample") is owned by International 
// Business Machines Corporation or one of its subsidiaries ("IBM") and is 
// copyrighted and licensed, not sold. You may use, copy, modify, and 
// distribute the Sample in any form without payment to IBM, for the purpose of 
// assisting you in the development of your applications.
// 
// The Sample code is provided to you on an "AS IS" basis, without warranty of 
// any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR 
// IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do 
// not allow for the exclusion or limitation of implied warranties, so the above 
// limitations or exclusions may not apply to you. IBM shall not be liable for 
// any damages you suffer as a result of using, copying, modifying or 
// distributing the Sample, even if IBM has been advised of the possibility of 
// such damages.
//***************************************************************************
//
// SOURCE FILE NAME: JCCSimpleGSSContext.java
//
// SAMPLE: This file is used by JCCSimpleGSSPlugin to implement a JCC
//         GSS-API plugin sample
//
//               None
//***************************************************************************
//
// For more information on the sample programs, see the README file.
//
// For information on developing Java applications see the Developing Java Applications book.
//
// For information on using SQL statements, see the SQL Reference.
//
// For the latest information on programming, compiling, and running DB2
// applications, visit the DB2 Information Center at
//     http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/index.jsp
//**************************************************************************/

import java.io.InputStream;
import java.io.OutputStream;
import org.ietf.jgss.*;

public  class JCCSimpleGSSContext implements org.ietf.jgss.GSSContext
{
  private JCCSimpleGSSCredential source_;
  private JCCSimpleGSSName target_;
  private int ctxCount_;
  private boolean anonymity_;
  private boolean dataConfidentiality_;
  private boolean credentialDelegation_;
  private boolean dataIntegrity_;
  private int  lifetime_;
  private boolean mutualAuth_;
  private boolean replayDetection_;
  private boolean sequenceChecking_;

  public JCCSimpleGSSContext(JCCSimpleGSSCredential source, JCCSimpleGSSName target, int ctxCount)
  {
    source_ = source;
    target_ = target;
    ctxCount_ = ctxCount;
  }

  public JCCSimpleGSSCredential getSource()
  {
    return source_;
  }

  public JCCSimpleGSSName getTarget()
  {
    return target_;
  }

  public int getctxCount()
  {
    return ctxCount_;
  }

  public void setSource(JCCSimpleGSSCredential source)
  {
    source_ = source;
  }

  public void setTarget(JCCSimpleGSSName target)
  {
    target_ = target;
  }

  public void setctxCount(int count)
  {
    ctxCount_ = count;
  }

  /**
  *
  * @return a byte[] containing the token to be sent to the
  * peer. <code>null</code> indicates that no token is generated.
  * @param byteArray token generated by the peer. This parameter is ignored
  * on the first call since no token has been received from the peer.
  * @param start the offset within the inputBuf where the token begins.
  * @param len the length of the token.
  *
  * @throws GSSException containing the following
  * major error codes:
  *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
  *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
  *   {@link GSSException#NO_CRED GSSException.NO_CRED},
  *   {@link GSSException#CREDENTIALS_EXPIRED
  *                                  GSSException.CREDENTIALS_EXPIRED},
  *   {@link GSSException#BAD_BINDINGS GSSException.BAD_BINDINGS},
  *   {@link GSSException#OLD_TOKEN GSSException.OLD_TOKEN},
  *   {@link GSSException#DUPLICATE_TOKEN GSSException.DUPLICATE_TOKEN},
  *   {@link GSSException#BAD_NAMETYPE GSSException.BAD_NAMETYPE},
  *   {@link GSSException#BAD_MECH GSSException.BAD_MECH},
  *   {@link GSSException#FAILURE GSSException.FAILURE}
  */
  public byte[] initSecContext(byte[] byteArray, int start, int len) throws GSSException
  {
      if (this.ctxCount_ ==0) {
        if (byteArray == null) {

          int useridlen = source_.getUserid().length();
          int pwdlen = source_.getPassword().length();
          int targetlen = target_.getUserid().length();

          /*
           Format of the token in gssapi_simple.c on server side

            #define TOKEN_MAX_STRLEN	64
            typedef struct _token{
            int useridLen;
            char userid[TOKEN_MAX_STRLEN];
            int pwdLen;
            char pwd[TOKEN_MAX_STRLEN];
            int targetLen;
            char target[TOKEN_MAX_STRLEN];
            OM_uint32 retFlags;
                   } TOKEN_T;

           So the length of the token is 4 + 64 + 4 + 64 + 4 + 64 + 4 = 208
           */
          int tokenLength = 208;
          byte[] tokenb = new byte[tokenLength];
          int offset = 0;

          //4 byte userid length
          tokenb[offset++] = (byte) ( (useridlen >>> 24) & 0xff);
          tokenb[offset++] = (byte) ( (useridlen >>> 16) & 0xff);
          tokenb[offset++] = (byte) ( (useridlen >>> 8) & 0xff);
          tokenb[offset++] = (byte) (useridlen & 0xff);

          //userid in byte format
          byte[] useridb = source_.getUserid().getBytes();
          for (int i = offset; i < offset + useridb.length; i++)
            tokenb[i] = useridb[i - offset];
          offset += useridb.length;
          //pad with blank 0x20 if the length of userid is less than 64
          for (int i = offset; i < 68; i++)
            tokenb[i] = 0x20;

          offset = 68;

          //4 byte password length
          tokenb[offset++] = (byte) ( (pwdlen >>> 24) & 0xff);
          tokenb[offset++] = (byte) ( (pwdlen >>> 16) & 0xff);
          tokenb[offset++] = (byte) ( (pwdlen >>> 8) & 0xff);
          tokenb[offset++] = (byte) (pwdlen & 0xff);

          //password in byte format
          byte[] pwdb = source_.getPassword().getBytes();
          for (int i = offset; i < offset + pwdb.length; i++)
            tokenb[i] = pwdb[i - offset];
          offset += pwdb.length;
          //pad with blank 0x20 if the passwor is less than 64
          for (int i = offset; i < 68 * 2; i++)
            tokenb[i] = 0x20;

          offset = 136;

          //4 byte server principal name length
          tokenb[offset++] = (byte) ( (targetlen >>> 24) & 0xff);
          tokenb[offset++] = (byte) ( (targetlen >>> 16) & 0xff);
          tokenb[offset++] = (byte) ( (targetlen >>> 8) & 0xff);
          tokenb[offset++] = (byte) (targetlen & 0xff);

          //server principal name in byte format
          byte[] targetb = target_.getUserid().getBytes();
          for (int i = offset; i < offset + targetb.length; i++)
            tokenb[i] = targetb[i - offset];
          offset += targetb.length;
          //pad with blank 0x20 if server principal is less than 64
          for (int i = offset; i < 68 * 3; i++)
            tokenb[i] = 0x20;

          offset = 68 * 3;

          //retFlags
          tokenb[offset++] = 0;
          tokenb[offset++] = 0;
          tokenb[offset++] = 0;
          tokenb[offset++] = 1;
          ctxCount_++;
          return tokenb;
        }
        else {  //consistant with gssapi_simple.c, if input_token != GSS_C_NO_BUFFER, throw error
          throw new JCCSimpleGSSException(0,"bad input token");
        }

      }
      else if (this.ctxCount_ == 1)  {
        //second invokation
        //sanity check
        ctxCount_++;
        if (len != 208)
          throw new JCCSimpleGSSException(0,"bad input token");
        else {
          return null; //don't send more token to server
        }

      }
      else
        throw new JCCSimpleGSSException(0,"context count too high");
   }

     /**
     *
     * @return the number of bytes written to the OutputStream as part of the
     * token to be sent to the peer. A value of 0 indicates that no token
     * needs to be sent.
     * @param inStream an InputStream that contains the token generated by
     * the peer. This parameter is ignored on the first call since no token
     * has been or will be received from the peer at that point.
     * @param outStream an OutputStream where the output token will be
     * written. During the final stage of context establishment, there may be
     * no bytes written.
     *
     * @throws GSSException containing the following
     * major error codes:
     *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
     *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
     *   {@link GSSException#NO_CRED GSSException.NO_CRED},
     *   {@link GSSException#CREDENTIALS_EXPIRED GSSException.CREDENTIALS_EXPIRED},
     *   {@link GSSException#BAD_BINDINGS GSSException.BAD_BINDINGS},
     *   {@link GSSException#OLD_TOKEN GSSException.OLD_TOKEN},
     *   {@link GSSException#DUPLICATE_TOKEN GSSException.DUPLICATE_TOKEN},
     *   {@link GSSException#BAD_NAMETYPE GSSException.BAD_NAMETYPE},
     *   {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *   {@link GSSException#FAILURE GSSException.FAILURE}
     */
  public int initSecContext(InputStream inputStream, OutputStream outputStream) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"initSecContext(InputStream inputStream, OutputStream outputStream) is not implemented");
  }

 /*
 * @return a byte[] containing the token to be sent to the
 * peer. <code>null</code> indicates that no token is generated.
 * @param inToken token generated by the peer.
 * @param offset the offset within the inToken where the token begins.
 * @param len the length of the token.
 *
 * @throws GSSException containing the following
 * major error codes:
 *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
 *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
 *   {@link GSSException#NO_CRED GSSException.NO_CRED},
 *   {@link GSSException#CREDENTIALS_EXPIRED
 *                               GSSException.CREDENTIALS_EXPIRED},
 *   {@link GSSException#BAD_BINDINGS GSSException.BAD_BINDINGS},
 *   {@link GSSException#OLD_TOKEN GSSException.OLD_TOKEN},
 *   {@link GSSException#DUPLICATE_TOKEN GSSException.DUPLICATE_TOKEN},
 *   {@link GSSException#BAD_MECH GSSException.BAD_MECH},
 *   {@link GSSException#FAILURE GSSException.FAILURE}
 */

  public byte[] acceptSecContext(byte[] inToken, int offset, int len) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"acceptSecContext(byte[] inToken, int offset, int len) is not implemented");
  }

 /*
  * @param inputStream an InputStream that contains the token generated by
  * the peer.
  * @param outStream an OutputStream where the output token will be
  * written. During the final stage of context establishment, there may be
  * no bytes written.
  *
  * @throws GSSException containing the following
  * major error codes:
  *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
  *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
  *   {@link GSSException#NO_CRED GSSException.NO_CRED},
  *   {@link GSSException#CREDENTIALS_EXPIRED
  *                           GSSException.CREDENTIALS_EXPIRED},
  *   {@link GSSException#BAD_BINDINGS GSSException.BAD_BINDINGS},
  *   {@link GSSException#OLD_TOKEN GSSException.OLD_TOKEN},
  *   {@link GSSException#DUPLICATE_TOKEN GSSException.DUPLICATE_TOKEN},
  *   {@link GSSException#BAD_MECH GSSException.BAD_MECH},
  *   {@link GSSException#FAILURE GSSException.FAILURE}
  */
  public void acceptSecContext(InputStream inputStream, OutputStream outputStream) throws GSSException
  {
     throw new JCCSimpleGSSException(0,"acceptSecContext(InputStream inputStream, OutputStream outputStream) is not implemented.");
  }

  /**
   * Used during context establishment to determine the state of the
   * context.
   *
   * @return <code>true</code> if this is a fully established context on
   * the caller's side and no more tokens are needed from the peer.
   */

  public boolean isEstablished()
  {
    return false;  //not used by jcc. always return false
  }

  /**
   * Releases any system resources and cryptographic information stored in
   * the context object and invalidates the context.
   *
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void dispose() throws GSSException  //gss_delete_sec_context
  {
    source_ = null;
    target_ = null;
    ctxCount_ = 0;

  }

  /**
   * Used to determine limits on the size of the message
   * that can be passed to <code>wrap</code>. Returns the maximum
   * message size that, if presented to the <code>wrap</code> method with
   * the same <code>confReq</code> and <code>qop</code> parameters, will
   * result in an output token containing no more
   * than <code>maxTokenSize</code> bytes.<p>
   *
   * This call is intended for use by applications that communicate over
   * protocols that impose a maximum message size.  It enables the
   * application to fragment messages prior to applying protection.<p>
   *
   * GSS-API implementations are recommended but not required to detect
   * invalid QOP values when <code>getWrapSizeLimit</code> is called.
   * This routine guarantees only a maximum message size, not the
   * availability of specific QOP values for message protection.<p>
   *
   * @param qop the level of protection wrap will be asked to provide.
   * @param confReq <code>true</code> if wrap will be asked to provide
   * privacy, <code>false</code>  otherwise.
   * @param maxTokenSize the desired maximum size of the token emitted by
   * wrap.
   * @return the maximum size of the input token for the given output
   * token size
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#BAD_QOP GSSException.BAD_QOP},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public int getWrapSizeLimit(int qop, boolean confReq,
                              int maxTokenSize) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"getWrapSizeLimit(int qop, boolean confReq,int maxTokenSize) is not implmented.");
  }

  /**
   * Applies per-message security services over the established security
   * context. The method will return a token with the
   * application supplied data and a cryptographic MIC over it.
   * The data may be encrypted if confidentiality (privacy) was
   * requested.<p>
   *
   * The MessageProp object is instantiated by the application and used
   * to specify a QOP value which selects cryptographic algorithms, and a
   * privacy service to optionally encrypt the message.  The underlying
   * mechanism that is used in the call may not be able to provide the
   * privacy service.  It sets the actual privacy service that it does
   * provide in this MessageProp object which the caller should then
   * query upon return.  If the mechanism is not able to provide the
   * requested QOP, it throws a GSSException with the BAD_QOP code.<p>
   *
   * Since some application-level protocols may wish to use tokens
   * emitted by wrap to provide "secure framing", implementations should
   * support the wrapping of zero-length messages.<p>
   *
   * The application will be responsible for sending the token to the
   * peer.
   *
   * @param inBuf application data to be protected.
   * @param offset the offset within the inBuf where the data begins.
   * @param len the length of the data
   * @param msgProp instance of MessageProp that is used by the
   * application to set the desired QOP and privacy state. Set the
   * desired QOP to 0 to request the default QOP. Upon return from this
   * method, this object will contain the the actual privacy state that
   * was applied to the message by the underlying mechanism.
   * @return a byte[] containing the token to be sent to the peer.
   *
   * @throws GSSException containing the following major error codes:
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#BAD_QOP GSSException.BAD_QOP},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public byte[] wrap(byte inBuf[], int offset, int len,
                     MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"wrap(byte inBuf[], int offset, int len, MessageProp msgProp) is not implmented.");
  }

  /**
   * Applies per-message security services over the established security
   * context using streams. The method will return a
   * token with the application supplied data and a cryptographic MIC over it.
   * The data may be encrypted if confidentiality
   * (privacy) was requested. This method is equivalent to the byte array
   * based {@link #wrap(byte[], int, int, MessageProp) wrap} method.<p>
   *
   * The application will be responsible for sending the token to the
   * peer.  Typically, the application would
   * ensure this by calling the  {@link java.io.OutputStream#flush() flush}
   * method on an <code>OutputStream</code> that encapsulates the
   * connection between the two peers.<p>
   *
   * The MessageProp object is instantiated by the application and used
   * to specify a QOP value which selects cryptographic algorithms, and a
   * privacy service to optionally encrypt the message.  The underlying
   * mechanism that is used in the call may not be able to provide the
   * privacy service.  It sets the actual privacy service that it does
   * provide in this MessageProp object which the caller should then
   * query upon return.  If the mechanism is not able to provide the
   * requested QOP, it throws a GSSException with the BAD_QOP code.<p>
   *
   * Since some application-level protocols may wish to use tokens
   * emitted by wrap to provide "secure framing", implementations should
   * support the wrapping of zero-length messages.<p>
   *
   * @param inStream an InputStream containing the application data to be
   * protected. All of the data that is available in
   * inStream is used.
   * @param outStream an OutputStream to write the protected message
   * to.
   * @param msgProp instance of MessageProp that is used by the
   * application to set the desired QOP and privacy state. Set the
   * desired QOP to 0 to request the default QOP. Upon return from this
   * method, this object will contain the the actual privacy state that
   * was applied to the message by the underlying mechanism.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#BAD_QOP GSSException.BAD_QOP},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void wrap(InputStream inStream, OutputStream outStream,
                   MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"wrap(InputStream inStream, OutputStream outStream, MessageProp msgProp) is not implmented.");
  }

  /**
   * Used to process tokens generated by the <code>wrap</code> method on
   * the other side of the context. The method will return the message
   * supplied by the peer application to its wrap call, while at the same
   * time verifying the embedded MIC for that message.<p>
   *
   * The MessageProp object is instantiated by the application and is
   * used by the underlying mechanism to return information to the caller
   * such as the QOP, whether confidentiality was applied to the message,
   * and other supplementary message state information.<p>
   *
   * Since some application-level protocols may wish to use tokens
   * emitted by wrap to provide "secure framing", implementations should
   * support the wrapping and unwrapping of zero-length messages.<p>
   *
   * @param inBuf a byte array containing the wrap token received from
   * peer.
   * @param offset the offset where the token begins.
   * @param len the length of the token
   * @param msgProp upon return from the method, this object will contain
   * the applied QOP, the privacy state of the message, and supplementary
   * information stating if the token was a duplicate, old, out of
   * sequence or arriving after a gap.
   * @return a byte[] containing the message unwrapped from the input
   * token.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
   *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public byte [] unwrap(byte[] inBuf, int offset, int len,
                        MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"unwrap(byte[] inBuf, int offset, int len, MessageProp msgProp) is not implmented.");
  }

  /**
   * Uses streams to process tokens generated by the <code>wrap</code>
   * method on the other side of the context. The method will return the
   * message supplied by the peer application to its wrap call, while at
   * the same time verifying the embedded MIC for that message.<p>
   *
   * The MessageProp object is instantiated by the application and is
   * used by the underlying mechanism to return information to the caller
   * such as the QOP, whether confidentiality was applied to the message,
   * and other supplementary message state information.<p>
   *
   * Since some application-level protocols may wish to use tokens
   * emitted by wrap to provide "secure framing", implementations should
   * support the wrapping and unwrapping of zero-length messages.<p>
   *
   * The format of the input token that this method
   * reads is defined in the specification for the underlying mechanism that
   * will be used. This method will attempt to read one of these tokens per
   * invocation. If the mechanism token contains a definitive start and
   * end this method may block on the <code>InputStream</code> if only
   * part of the token is available. If the start and end of the token
   * are not definitive then the method will attempt to treat all
   * available bytes as part of the token.<p>
   *
   * Other than the possible blocking behaviour described above, this
   * method is equivalent to the byte array based {@link #unwrap(byte[],
   * int, int, MessageProp) unwrap} method.<p>
   *
   * @param inStream an InputStream that contains the wrap token generated
   * by the peer.
   * @param outStream an OutputStream to write the application message
   * to.
   * @param msgProp upon return from the method, this object will contain
   * the applied QOP, the privacy state of the message, and supplementary
   * information stating if the token was a duplicate, old, out of
   * sequence or arriving after a gap.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN},
   *   {@link GSSException#BAD_MIC GSSException.BAD_MIC},
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void unwrap(InputStream inStream, OutputStream outStream,
                     MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"public void unwrap(InputStream inStream, OutputStream outStream, MessageProp msgProp) is not implmented.");
  }

  /**
   * Returns a token containing a cryptographic Message Integrity Code
   * (MIC) for the supplied message,  for transfer to the peer
   * application.  Unlike wrap, which encapsulates the user message in the
   * returned token, only the message MIC is returned in the output
   * token.<p>
   *
   * Note that privacy can only be applied through the wrap call.<p>
   *
   * Since some application-level protocols may wish to use tokens emitted
   * by getMIC to provide "secure framing", implementations should support
   * derivation of MICs from zero-length messages.
   *
   * @param inMsg the message to generate the MIC over.
   * @param offset offset within the inMsg where the message begins.
   * @param len the length of the message
   * @param msgProp an instance of <code>MessageProp</code> that is used
   * by the application to set the desired QOP.  Set the desired QOP to
   * <code>0</code> in <code>msgProp</code> to request the default
   * QOP. Alternatively pass in <code>null</code> for <code>msgProp</code>
   * to request the default QOP.
   * @return a byte[] containing the token to be sent to the peer.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#BAD_QOP GSSException.BAD_QOP},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public byte[] getMIC(byte []inMsg, int offset, int len,
                       MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"getMIC(byte []inMsg, int offset, int len, MessageProp msgProp) is not implmented.");
  }

  /**
   * Uses streams to produce a token containing a cryptographic MIC for
   * the supplied message, for transfer to the peer application.
   * Unlike wrap, which encapsulates the user message in the returned
   * token, only the message MIC is produced in the output token. This
   * method is equivalent to the byte array based {@link #getMIC(byte[],
   * int, int, MessageProp) getMIC} method.
   *
   * Note that privacy can only be applied through the wrap call.<p>
   *
   * Since some application-level protocols may wish to use tokens emitted
   * by getMIC to provide "secure framing", implementations should support
   * derivation of MICs from zero-length messages.
   *
   * @param inStream an InputStream containing the message to generate the
   * MIC over. All of the data that is available in
   * inStream is used.
   * @param outStream an OutputStream to write the output token to.
   * @param msgProp an instance of <code>MessageProp</code> that is used
   * by the application to set the desired QOP.  Set the desired QOP to
   * <code>0</code> in <code>msgProp</code> to request the default
   * QOP. Alternatively pass in <code>null</code> for <code>msgProp</code>
   * to request the default QOP.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#BAD_QOP GSSException.BAD_QOP},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void getMIC(InputStream inStream, OutputStream outStream,
                     MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"getMIC(InputStream inStream, OutputStream outStream, MessageProp msgProp) is not implmented.");
  }

  /**
  * Verifies the cryptographic MIC, contained in the token parameter,
  * over the supplied message.<p>
  *
  * The MessageProp object is instantiated by the application and is used
  * by the underlying mechanism to return information to the caller such
  * as the QOP indicating the strength of protection that was applied to
  * the message and other supplementary message state information.<p>
  *
  * Since some application-level protocols may wish to use tokens emitted
  * by getMIC to provide "secure framing", implementations should support
  * the calculation and verification of MICs over zero-length messages.
  *
  * @param inToken the token generated by peer's getMIC method.
  * @param tokOffset the offset within the inToken where the token
  * begins.
  * @param tokLen the length of the token.
  * @param inMsg the application message to verify the cryptographic MIC
  * over.
  * @param msgOffset the offset in inMsg where the message begins.
  * @param msgLen the length of the message.
  * @param msgProp upon return from the method, this object will contain
  * the applied QOP and supplementary information stating if the token
  * was a duplicate, old, out of sequence or arriving after a gap.
  *
  * @throws GSSException containing the following
  * major error codes:
  *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN}
  *   {@link GSSException#BAD_MIC GSSException.BAD_MIC}
  *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED}
  *   {@link GSSException#FAILURE GSSException.FAILURE}
  */
 public void verifyMIC(byte[] inToken, int tokOffset, int tokLen,
                       byte[] inMsg, int msgOffset, int msgLen,
                       MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"verifyMIC(byte[] inToken, int tokOffset, int tokLen, byte[] inMsg, int msgOffset, int msgLen, MessageProp msgProp) is not implmented.");
  }

  /**
   * Uses streams to verify the cryptographic MIC, contained in the token
   * parameter, over the supplied message.  This method is equivalent to
   * the byte array based {@link #verifyMIC(byte[], int, int, byte[], int,
   * int, MessageProp) verifyMIC} method.
   *
   * The MessageProp object is instantiated by the application and is used
   * by the underlying mechanism to return information to the caller such
   * as the QOP indicating the strength of protection that was applied to
   * the message and other supplementary message state information.<p>
   *
   * Since some application-level protocols may wish to use tokens emitted
   * by getMIC to provide "secure framing", implementations should support
   * the calculation and verification of MICs over zero-length messages.<p>
   *
   * The format of the input token that this method
   * reads is defined in the specification for the underlying mechanism that
   * will be used. This method will attempt to read one of these tokens per
   * invocation. If the mechanism token contains a definitive start and
   * end this method may block on the <code>InputStream</code> if only
   * part of the token is available. If the start and end of the token
   * are not definitive then the method will attempt to treat all
   * available bytes as part of the token.<p>
   *
   * Other than the possible blocking behaviour described above, this
   * method is equivalent to the byte array based {@link #verifyMIC(byte[],
   * int, int, byte[], int, int, MessageProp) verifyMIC} method.<p>
   *
   * @param tokStream an InputStream containing the token generated by the
   * peer's getMIC method.
   * @param msgStream an InputStream containing the application message to
   * verify the cryptographic MIC over. All of the data
   * that is available in msgStream is used.
   * @param msgProp upon return from the method, this object will contain
   * the applied QOP and supplementary information stating if the token
   * was a duplicate, old, out of sequence or arriving after a gap.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#DEFECTIVE_TOKEN GSSException.DEFECTIVE_TOKEN}
   *   {@link GSSException#BAD_MIC GSSException.BAD_MIC}
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED}
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void verifyMIC(InputStream tokStream, InputStream msgStream,
                        MessageProp msgProp) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"verifyMIC(InputStream tokStream, InputStream msgStream, MessageProp msgProp) is not implmented.");
  }

  /**
   * Exports this context so that another process may
   * import it.. Provided to support the sharing of work between
   * multiple processes. This routine will typically be used by the
   * context-acceptor, in an application where a single process receives
   * incoming connection requests and accepts security contexts over
   * them, then passes the established context to one or more other
   * processes for message exchange.<p>
   *
   * This method deactivates the security context and creates an
   * interprocess token which, when passed to {@link
   * GSSManager#createContext(byte[]) GSSManager.createContext} in
   * another process, will re-activate the context in the second process.
   * Only a single instantiation of a given context may be active at any
   * one time; a subsequent attempt by a context exporter to access the
   * exported security context will fail.<p>
   *
   * The implementation may constrain the set of processes by which the
   * interprocess token may be imported, either as a function of local
   * security policy, or as a result of implementation decisions.  For
   * example, some implementations may constrain contexts to be passed
   * only between processes that run under the same account, or which are
   * part of the same process group.<p>
   *
   * The interprocess token may contain security-sensitive information
   * (for example cryptographic keys).  While mechanisms are encouraged
   * to either avoid placing such sensitive information within
   * interprocess tokens, or to encrypt the token before returning it to
   * the application, in a typical GSS-API implementation this may not be
   * possible.  Thus the application must take care to protect the
   * interprocess token, and ensure that any process to which the token
   * is transferred is trustworthy. <p>
   *
   * Implementations are not required to support the inter-process
   * transfer of security contexts.  Calling the {@link #isTransferable()
   * isTransferable} method will indicate if the context object is
   * transferable.<p>
   *
   * Calling this method on a context that
   * is not exportable will result in this exception being thrown with
   * the error code {@link GSSException#UNAVAILABLE
   * GSSException.UNAVAILABLE}.
   *
   * @return a byte[] containing the exported context
   * @see GSSManager#createContext(byte[])
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#UNAVAILABLE GSSException.UNAVAILABLE},
   *   {@link GSSException#CONTEXT_EXPIRED GSSException.CONTEXT_EXPIRED},
   *   {@link GSSException#NO_CONTEXT GSSException.NO_CONTEXT},
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public byte [] export() throws GSSException
  {
    throw new JCCSimpleGSSException(0,"export() is not implmented.");
  }

  /**
   * Requests that mutual authentication be done during
   * context establishment. This request can only be made on the context
   * initiator's side and it has to be done prior to the first call to
   * <code>initSecContext</code>.<p>
   *
   * Not all mechanisms support mutual authentication and some mechanisms
   * might require mutual authentication even if the application
   * doesn't. Therefore, the application should check to see if the
   * request was honored with the {@link #getMutualAuthState()
   * getMutualAuthState} method.<p>
   *
   * @param state a boolean value indicating whether mutual
   * authentication shouls be used or not.
   * @see #getMutualAuthState()
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestMutualAuth(boolean state) throws GSSException
  {
    mutualAuth_ = state;
  }

  /**
   * Requests that replay detection be enabled for the
   * per-message security services after context establishemnt. This
   * request can only be made on the context initiator's side and it has
   * to be done prior to the first call to
   * <code>initSecContext</code>. During context establishment replay
   * detection is not an option and is a function of the underlying
   * mechanism's capabilities.<p>
   *
   * Not all mechanisms support replay detection and some mechanisms
   * might require replay detection even if the application
   * doesn't. Therefore, the application should check to see if the
   * request was honored with the {@link #getReplayDetState()
   * getReplayDetState} method. If replay detection is enabled then the
   * {@link MessageProp#isDuplicateToken() MessageProp.isDuplicateToken} and {@link
   * MessageProp#isOldToken() MessageProp.isOldToken} methods will return
   * valid results for the <code>MessageProp</code> object that is passed
   * in to the <code>unwrap</code> method or the <code>verifyMIC</code>
   * method.<p>
   *
   * @param state a boolean value indicating whether replay detection
   * should be enabled over the established context or not.
   * @see #getReplayDetState()
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestReplayDet(boolean state) throws GSSException
  {
    replayDetection_ = state;
  }

  /**
  * Requests that sequence checking be enabled for the
  * per-message security services after context establishemnt. This
  * request can only be made on the context initiator's side and it has
  * to be done prior to the first call to
  * <code>initSecContext</code>. During context establishment sequence
  * checking is not an option and is a function of the underlying
  * mechanism's capabilities.<p>
  *
  * Not all mechanisms support sequence checking and some mechanisms
  * might require sequence checking even if the application
  * doesn't. Therefore, the application should check to see if the
  * request was honored with the {@link #getSequenceDetState()
  * getSequenceDetState} method. If sequence checking is enabled then the
  * {@link MessageProp#isDuplicateToken() MessageProp.isDuplicateToken},
  * {@link MessageProp#isOldToken() MessageProp.isOldToken},
  * {@link MessageProp#isUnseqToken() MessageProp.isUnseqToken}, and
  * {@link MessageProp#isGapToken() MessageProp.isGapToken} methods will return
  * valid results for the <code>MessageProp</code> object that is passed
  * in to the <code>unwrap</code> method or the <code>verifyMIC</code>
  * method.<p>
  *
  * @param state a boolean value indicating whether sequence checking
  * should be enabled over the established context or not.
  * @see #getSequenceDetState()
  *
  * @throws GSSException containing the following
  * major error codes:
  *   {@link GSSException#FAILURE GSSException.FAILURE}
  */
  public void requestSequenceDet(boolean state) throws GSSException
  {
    sequenceChecking_ = state;
  }

  /**
   * Requests that the initiator's credentials be
   * delegated to the acceptor during context establishment. This
   * request can only be made on the context initiator's side and it has
   * to be done prior to the first call to
   * <code>initSecContext</code>.
   *
   * Not all mechanisms support credential delegation. Therefore, an
   * application that desires delegation should check to see if the
   * request was honored with the {@link #getCredDelegState()
   * getCredDelegState} method. If the application indicates that
   * delegation must not be used, then the mechanism will honor the
   * request and delegation will not occur. This is an exception
   * to the general rule that a mechanism may enable a service even if it
   * is not requested.<p>
   *
   * @param state a boolean value indicating whether the credentials
   * should be delegated or not.
   * @see #getCredDelegState()
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestCredDeleg(boolean state) throws GSSException
  {
    credentialDelegation_ = state;
  }

  /**
   * Requests that the initiator's identity not be
   * disclosed to the acceptor. This request can only be made on the
   * context initiator's side and it has to be done prior to the first
   * call to <code>initSecContext</code>.
   *
   * Not all mechanisms support anonymity for the initiator. Therefore, the
   * application should check to see if the request was honored with the
   * {@link #getAnonymityState() getAnonymityState} method.<p>
   *
   * @param state a boolean value indicating if the initiator should
   * be authenticated to the acceptor as an anonymous principal.
   * @see #getAnonymityState
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestAnonymity(boolean state) throws GSSException
  {
    anonymity_ = state;
  }

  /**
   * Requests that data confidentiality be enabled
   * for the <code>wrap</code> method. This request can only be made on
   * the context initiator's side and it has to be done prior to the
   * first call to <code>initSecContext</code>.
   *
   * Not all mechanisms support confidentiality and other mechanisms
   * might enable it even if the application doesn't request
   * it. The application may check to see if the request was honored with
   * the {@link #getConfState() getConfState} method. If confidentiality
   * is enabled, only then will the mechanism honor a request for privacy
   * in the {@link MessageProp#MessageProp(int, boolean) MessageProp}
   * object that is passed in to the <code>wrap</code> method.<p>
   *
   * Enabling confidentiality will also automatically enable
   * integrity.<p>
   *
   * @param state a boolean value indicating whether confidentiality
   * should be enabled or not.
   * @see #getConfState()
   * @see #getIntegState()
   * @see #requestInteg(boolean)
   * @see MessageProp
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestConf(boolean state) throws GSSException
  {
    dataConfidentiality_ = state;
  }

  /**
   * Requests that data confidentiality be enabled
   * for the <code>wrap</code> method. This request can only be made on
   * the context initiator's side and it has to be done prior to the
   * first call to <code>initSecContext</code>.
   *
   * Not all mechanisms support confidentiality and other mechanisms
   * might enable it even if the application doesn't request
   * it. The application may check to see if the request was honored with
   * the {@link #getConfState() getConfState} method. If confidentiality
   * is enabled, only then will the mechanism honor a request for privacy
   * in the {@link MessageProp#MessageProp(int, boolean) MessageProp}
   * object that is passed in to the <code>wrap</code> method.<p>
   *
   * Enabling confidentiality will also automatically enable
   * integrity.<p>
   *
   * @param state a boolean value indicating whether confidentiality
   * should be enabled or not.
   * @see #getConfState()
   * @see #getIntegState()
   * @see #requestInteg(boolean)
   * @see MessageProp
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestInteg(boolean state) throws GSSException
  {
    dataIntegrity_ = state;
  }

  /**
   * Requests a lifetime in seconds for the
   * context. This method can only be called on the context initiator's
   * side  and it has to be done prior to the first call to
   * <code>initSecContext</code>.<p>
   *
   * The actual lifetime of the context will depend on the capabilites of
   * the underlying mechanism and the application should call the {@link
   * #getLifetime() getLifetime} method to determine this.<p>
   *
   * @param lifetime the desired context lifetime in seconds. Use
   * <code>INDEFINITE_LIFETIME</code> to request an indefinite lifetime
   * and <code>DEFAULT_LIFETIME</code> to request a default lifetime.
   * @see #getLifetime()
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void requestLifetime(int lifetime) throws GSSException
  {
    lifetime_ = lifetime;
  }

  /**
   * Sets the channel bindings to be used during context
   * establishment. This method can be called on both
   * the context initiator's and the context acceptor's side, but it must
   * be called before context establishment begins. This means that an
   * initiator must call it before the first call to
   * <code>initSecContext</code> and the acceptor must call it before the
   * first call to <code>acceptSecContext</code>.
   *
   * @param cb the channel bindings to use.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public void setChannelBinding(ChannelBinding channelBinding) throws GSSException
  {
    throw new JCCSimpleGSSException(0,"setChannelBinding(ChannelBinding channelBinding) is not implmented.");
  }

  /**
   * Determines if credential delegation is enabled on
   * this context. It can be called by both the context initiator and the
   * context acceptor. For a definitive answer this method must be
   * called only after context establishment is complete. Note that if an
   * initiator requests that delegation not be allowed the {@link
   * #requestCredDeleg(boolean) requestCredDeleg} method will honor that
   * request and this method will return <code>false</code> on the
   * initiator's side from that point onwards. <p>
   *
   * @return true if delegation is enabled, false otherwise.
   * @see #requestCredDeleg(boolean)
   */
  public boolean getCredDelegState()
  {
    return credentialDelegation_;
  }

  /**
   * Determines if mutual authentication is enabled on
   * this context. It can be called by both the context initiator and the
   * context acceptor. For a definitive answer this method must be
   * called only after context establishment is complete. An initiator
   * that requests mutual authentication can call this method after
   * context completion and dispose the context if its request was not
   * honored.<p>
   *
   * @return true if mutual authentication is enabled, false otherwise.
   * @see #requestMutualAuth(boolean)
   */
  public boolean getMutualAuthState()
  {
    return mutualAuth_;
  }

  /**
   * Determines if replay detection is enabled for the
   * per-message security services from this context. It can be called by
   * both the context initiator and the context acceptor. For a
   * definitive answer this method must be called only after context
   * establishment is complete. An initiator that requests replay
   * detection can call this method after context completion and
   * dispose the context if its request was not honored.<p>
   *
   * @return true if replay detection is enabled, false otherwise.
   * @see #requestReplayDet(boolean)
   */
  public boolean getReplayDetState()
  {
    return replayDetection_;
  }

  /**
   * Determines if sequence checking is enabled for the
   * per-message security services from this context. It can be called by
   * both the context initiator and the context acceptor. For a
   * definitive answer this method must be called only after context
   * establishment is complete. An initiator that requests sequence
   * checking can call this method after context completion and
   * dispose the context if its request was not honored.<p>
   *
   * @return true if sequence checking is enabled, false otherwise.
   * @see #requestSequenceDet(boolean)
   */
  public boolean getSequenceDetState()
  {
    return sequenceChecking_;
  }

  /**
   * Determines if the context initiator is
   * anonymously authenticated to the context acceptor. It can be called by
   * both the context initiator and the context acceptor, and at any
   * time. <strong>On the initiator side, a call to this method determines
   * if the identity of the initiator has been disclosed in any of the
   * context establishment tokens that might have been generated thus far
   * by <code>initSecContext</code>. An initiator that absolutely must be
   * authenticated anonymously should call this method after each call to
   * <code>initSecContext</code> to determine if the generated token
   * should be sent to the peer or the context aborted.</strong> On the
   * acceptor side, a call to this method determines if any of the tokens
   * processed by <code>acceptSecContext</code> thus far have divulged
   * the identity of the initiator.<p>
   *
   * @return true if the context initiator is still anonymous, false
   * otherwise.
   * @see #requestAnonymity(boolean)
   */
  public boolean getAnonymityState()
  {
    return anonymity_;
  }

  /**
   * Determines if the context is transferable to other processes
   * through the use of the {@link #export() export} method.  This call
   * is only valid on fully established contexts.
   *
   * @return true if this context can be exported, false otherwise.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public boolean isTransferable() throws GSSException
  {
    throw new JCCSimpleGSSException(0,"isTransferable() is not implmented.");
  }

  /**
   * Determines if the context is ready for per message operations to be
   * used over it.  Some mechanisms may allow the usage of the
   * per-message operations before the context is fully established.
   *
   * @return true if methods like <code>wrap</code>, <code>unwrap</code>,
   * <code>getMIC</code>, and <code>verifyMIC</code> can be used with
   * this context at the current stage of context establishment, false
   * otherwise.
   */
  public boolean isProtReady()
  {
    return false;
  }

  /**
   * Determines if data confidentiality is available
   * over the context. This method can be called by both the context
   * initiator and the context acceptor, but only after one of {@link
   * #isProtReady() isProtReady} or {@link #isEstablished()
   * isEstablished} return <code>true</code>. If this method returns
   * <code>true</code>, so will {@link #getIntegState()
   * getIntegState}<p>
   *
   * @return true if confidentiality services are available, false
   * otherwise.
   * @see #requestConf(boolean)
   */
  public boolean getConfState()
  {
    return dataConfidentiality_;
  }

  /**
   * Determines if data integrity is available
   * over the context. This method can be called by both the context
   * initiator and the context acceptor, but only after one of {@link
   * #isProtReady() isProtReady} or {@link #isEstablished()
   * isEstablished} return <code>true</code>. This method will always
   * return <code>true</code> if {@link #getConfState() getConfState}
   * returns true.<p>
   *
   * @return true if integrity services are available, false otherwise.
   * @see #requestInteg(boolean)
   */
  public boolean getIntegState()
  {
    return dataIntegrity_;
  }

  /**
   * Determines what the remaining lifetime for this
   * context is. It can be called by both the context initiator and the
   * context acceptor, but for a definitive answer it should be called
   * only after {@link #isEstablished() isEstablished} returns
   * true.<p>
   *
   * @return the remaining lifetime in seconds
   * @see #requestLifetime(int)
   */
  public int getLifetime()
  {
    return lifetime_;
  }

  /**
   * Returns the name of the context initiator. This call is valid only
   * after one of {@link #isProtReady() isProtReady} or {@link
   * #isEstablished() isEstablished} return <code>true</code>.
   *
   * @return a GSSName that is an MN containing the name of the context
   * initiator.
   * @see GSSName
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public GSSName getSrcName() throws GSSException
  {
    return new JCCSimpleGSSName(source_.getUserid());
  }

  /**
   * Returns the name of the context acceptor. This call is valid only
   * after one of {@link #isProtReady() isProtReady} or {@link
   * #isEstablished() isEstablished} return <code>true</code>.
   *
   * @return a GSSName that is an MN containing the name of the context
   * acceptor.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public GSSName getTargName() throws GSSException
  {
    return target_;
  }

  /**
   * Determines what mechanism is being used for this
   * context. This method may be called before the context is fully
   * established, but the mechanism returned may change on successive
   * calls in the negotiated mechanism case.
   *
   * @return the Oid of the mechanism being used
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public Oid getMech() throws GSSException
  {
    throw new JCCSimpleGSSException(0,"getMech() is not implmented.");
  }

  /**
   * Obtains the credentials delegated by the context
   * initiator to the context acceptor. It should be called only on the
   * context acceptor's side, and once the context is fully
   * established. The caller can use the method {@link
   * #getCredDelegState() getCredDelegState} to determine if there are
   * any delegated credentials.
   *
   * @return a GSSCredential containing the initiator's delegated
   * credentials, or <code>null</code> is no credentials
   * were delegated.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public GSSCredential getDelegCred() throws GSSException
  {
    throw new JCCSimpleGSSException(0,"getDelegCred() is not implmented.");
  }

  /**
   * Determines if this is the context initiator. This
   * can be called on both the context initiator's and context acceptor's
   * side.
   *
   * @return true if this is the context initiator, false if it is the
   * context acceptor.
   *
   * @throws GSSException containing the following
   * major error codes:
   *   {@link GSSException#FAILURE GSSException.FAILURE}
   */
  public boolean isInitiator() throws GSSException
  {
    throw new JCCSimpleGSSException(0,"isInitiator() is not implmented.");
  }

}