cipher.java

gcc的组建

  public final int getBlockSize()
  {
    if (cipherSpi != null)
      {
        return cipherSpi.engineGetBlockSize();
      }
    return 1;
  }

  /**
   * Return the currently-operating {@link ExemptionMechanism}.
   *
   * @return null, currently.
   */
  public final ExemptionMechanism getExemptionMechanism()
  {
    return null;
  }

  /**
   * Return the <i>initialization vector</i> that this instance was
   * initialized with.
   *
   * @return The IV.
   */
  public final byte[] getIV()
  {
    if (cipherSpi != null)
      {
        return cipherSpi.engineGetIV();
      }
    return null;
  }

  /**
   * Return the {@link java.security.AlgorithmParameters} that this
   * instance was initialized with.
   *
   * @return The parameters.
   */
  public final AlgorithmParameters getParameters()
  {
    if (cipherSpi != null) {
      return cipherSpi.engineGetParameters();
    }
    return null;
  }

  /**
   * Return this cipher's provider.
   *
   * @return The provider.
   */
  public final Provider getProvider()
  {
    return provider;
  }

  /**
   * Finishes a multi-part transformation, and returns the final
   * transformed bytes.
   *
   * @return The final transformed bytes.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   * @throws javax.crypto.IllegalBlockSizeException If this instance has
   *         no padding and the input is not a multiple of this cipher's
   *         block size.
   * @throws javax.crypto.BadPaddingException If this instance is
   *         decrypting and the padding bytes do not match this
   *         instance's padding scheme.
   */
  public final byte[] doFinal()
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException
  {
    return doFinal(new byte[0], 0, 0);
  }

  /**
   * Finishes a multi-part transformation or does an entire
   * transformation on the input, and returns the transformed bytes.
   *
   * @param input The final input bytes.
   * @return The final transformed bytes.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   * @throws javax.crypto.IllegalBlockSizeException If this instance has
   *         no padding and the input is not a multiple of this cipher's
   *         block size.
   * @throws javax.crypto.BadPaddingException If this instance is
   *         decrypting and the padding bytes do not match this
   *         instance's padding scheme.
   */
  public final byte[] doFinal(byte[] input)
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException
  {
    return doFinal(input, 0, input.length);
  }

  /**
   * Finishes a multi-part transformation or does an entire
   * transformation on the input, and returns the transformed bytes.
   *
   * @param input       The final input bytes.
   * @param inputOffset The index in the input bytes to start.
   * @param inputLength The number of bytes to read from the input.
   * @return The final transformed bytes.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   * @throws javax.crypto.IllegalBlockSizeException If this instance has
   *         no padding and the input is not a multiple of this cipher's
   *         block size.
   * @throws javax.crypto.BadPaddingException If this instance is
   *         decrypting and the padding bytes do not match this
   *         instance's padding scheme.
   */
  public final byte[] doFinal(byte[] input, int inputOffset, int inputLength)
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException
  {
    if (cipherSpi == null)
      {
        byte[] b = new byte[inputLength];
        System.arraycopy(input, inputOffset, b, 0, inputLength);
        return b;
      }
    if (state != ENCRYPT_MODE && state != DECRYPT_MODE)
      {
        throw new IllegalStateException("neither encrypting nor decrypting");
      }
    state = INITIAL_STATE;
    return cipherSpi.engineDoFinal(input, inputOffset, inputLength);
  }

  /**
   * Finishes a multi-part transformation and stores the transformed
   * bytes into the given array.
   *
   * @param output       The destination for the transformed bytes.
   * @param outputOffset The offset in <tt>output</tt> to start storing
   *        bytes.
   * @return The number of bytes placed into the output array.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   * @throws javax.crypto.IllegalBlockSizeException If this instance has
   *         no padding and the input is not a multiple of this cipher's
   *         block size.
   * @throws javax.crypto.BadPaddingException If this instance is
   *         decrypting and the padding bytes do not match this
   *         instance's padding scheme.
   * @throws javax.crypto.ShortBufferException If the output array is
   *         not large enough to hold the transformed bytes.
   */
  public final int doFinal(byte[] output, int outputOffset)
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException,
           ShortBufferException
  {
    if (cipherSpi == null)
      {
        return 0;
      }
    if (state != ENCRYPT_MODE && state != DECRYPT_MODE)
      {
        throw new IllegalStateException("neither encrypting nor decrypting");
      }
    state = INITIAL_STATE;
    return cipherSpi.engineDoFinal(new byte[0], 0, 0, output, outputOffset);
  }

  /**
   * Finishes a multi-part transformation or transforms a portion of a
   * byte array, and stores the result in the given byte array.
   *
   * @param input        The input bytes.
   * @param inputOffset  The index in <tt>input</tt> to start.
   * @param inputLength  The number of bytes to transform.
   * @param output       The output buffer.
   * @param outputOffset The index in <tt>output</tt> to start.
   * @return The number of bytes placed into the output array.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   * @throws javax.crypto.IllegalBlockSizeException If this instance has
   *         no padding and the input is not a multiple of this cipher's
   *         block size.
   * @throws javax.crypto.BadPaddingException If this instance is
   *         decrypting and the padding bytes do not match this
   *         instance's padding scheme.
   * @throws javax.crypto.ShortBufferException If the output array is
   *         not large enough to hold the transformed bytes.
   */
  public final int doFinal(byte[] input, int inputOffset, int inputLength,
                           byte[] output, int outputOffset)
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException,
           ShortBufferException
  {
    if (cipherSpi == null)
      {
        if (inputLength > output.length - outputOffset)
          {
            throw new ShortBufferException();
          }
        System.arraycopy(input, inputOffset, output, outputOffset, inputLength);
        return inputLength;
      }
    if (state != ENCRYPT_MODE && state != DECRYPT_MODE)
      {
        throw new IllegalStateException("neither encrypting nor decrypting");
      }
    state = INITIAL_STATE;
    return cipherSpi.engineDoFinal(input, inputOffset, inputLength,
                                   output, outputOffset);
  }

  public final int doFinal(byte[] input, int inputOffset, int inputLength,
                           byte[] output)
    throws IllegalStateException, IllegalBlockSizeException, BadPaddingException,
           ShortBufferException
  {
    return doFinal(input, inputOffset, inputLength, output, 0);
  }

  /**
   * Returns the size an output buffer needs to be if this cipher is
   * updated with a number of bytes.
   *
   * @param inputLength The input length.
   * @return The output length given this input length.
   * @throws java.lang.IllegalStateException If this instance has not
   *         been initialized, or if a <tt>doFinal</tt> call has already
   *         been made.
   */
  public final int getOutputSize(int inputLength) throws IllegalStateException
  {
    if (cipherSpi == null)
      {
        return inputLength;
      }
    if (state != ENCRYPT_MODE && state != DECRYPT_MODE)
      {
        throw new IllegalStateException("neither encrypting nor decrypting");
      }
    return cipherSpi.engineGetOutputSize(inputLength);
  }

  /**
   * <p>Initialize this cipher with the public key from the given
   * certificate.</p>
   *
   * <p>The cipher will be initialized for encryption, decryption, key
   * wrapping, or key unwrapping, depending upon whether the
   * <code>opmode</code> argument is {@link #ENCRYPT_MODE}, {@link
   * #DECRYPT_MODE}, {@link #WRAP_MODE}, or {@link #UNWRAP_MODE},
   * respectively.</p>
   *
   * <p>As per the Java 1.4 specification, if <code>cert</code> is an
   * instance of an {@link java.security.cert.X509Certificate} and its
   * <i>key usage</i> extension field is incompatible with
   * <code>opmode</code> then an {@link
   * java.security.InvalidKeyException} is thrown.</p>
   *
   * <p>If this cipher requires any random bytes (for example for an
   * initilization vector) than the {@link java.security.SecureRandom}
   * with the highest priority is used as the source of these bytes.</p>
   *
   * <p>A call to any of the <code>init</code> methods overrides the
   * state of the instance, and is equivalent to creating a new instance
   * and calling its <code>init</code> method.</p>
   *
   * @param opmode      The operation mode to use.
   * @param certificate The certificate.
   * @throws java.security.InvalidKeyException If the underlying cipher
   *         instance rejects the certificate's public key, or if the
   *         public key cannot be used as described above.
   */
  public final void init(int opmode, Certificate certificate)
    throws InvalidKeyException
  {
    init(opmode, certificate, new SecureRandom());
  }

  /**
   * <p>Initialize this cipher with the supplied key.</p>
   *
   * <p>The cipher will be initialized for encryption, decryption, key
   * wrapping, or key unwrapping, depending upon whether the
   * <code>opmode</code> argument is {@link #ENCRYPT_MODE}, {@link
   * #DECRYPT_MODE}, {@link #WRAP_MODE}, or {@link #UNWRAP_MODE},
   * respectively.</p>
   *
   * <p>If this cipher requires any random bytes (for example for an
   * initilization vector) than the {@link java.security.SecureRandom}
   * with the highest priority is used as the source of these bytes.</p>
   *
   * <p>A call to any of the <code>init</code> methods overrides the
   * state of the instance, and is equivalent to creating a new instance
   * and calling its <code>init</code> method.</p>
   *
   * @param opmode The operation mode to use.
   * @param key    The key.
   * @throws java.security.InvalidKeyException If the underlying cipher
   *         instance rejects the given key.
   */
  public final void init(int opmode, Key key) throws InvalidKeyException
  {
    state = opmode;
    if (cipherSpi != null)
      {
        cipherSpi.engineInit(opmode, key, new SecureRandom());
      }
  }

  /**
   * <p>Initialize this cipher with the public key from the given
   * certificate and the specified source of randomness.</p>
   *
   * <p>The cipher will be initialized for encryption, decryption, key
   * wrapping, or key unwrapping, depending upon whether the
   * <code>opmode</code> argument is {@link #ENCRYPT_MODE}, {@link
   * #DECRYPT_MODE}, {@link #WRAP_MODE}, or {@link #UNWRAP_MODE},
   * respectively.</p>
   *
   * <p>As per the Java 1.4 specification, if <code>cert</code> is an
   * instance of an {@link java.security.cert.X509Certificate} and its
   * <i>key usage</i> extension field is incompatible with
   * <code>opmode</code> then an {@link
   * java.security.InvalidKeyException} is thrown.</p>
   *
   * <p>If this cipher requires any random bytes (for example for an
   * initilization vector) than the {@link java.security.SecureRandom}
   * with the highest priority is used as the source of these bytes.</p>
   *
   * <p>A call to any of the <code>init</code> methods overrides the
   * state of the instance, and is equivalent to creating a new instance
   * and calling its <code>init</code> method.</p>
   *
   * @param opmode      The operation mode to use.
   * @param certificate The certificate.
   * @param random      The source of randomness.
   * @throws java.security.InvalidKeyException If the underlying cipher
   *         instance rejects the certificate's public key, or if the
   *         public key cannot be used as described above.
   */
  public final void
  init(int opmode, Certificate certificate, SecureRandom random)
  throws InvalidKeyException
  {
    if (certificate instanceof X509Certificate)
      {
        boolean[] keyInfo = ((X509Certificate) certificate).getKeyUsage();
        if (keyInfo != null)
          {
            switch (opmode)
              {
              case DECRYPT_MODE:
                if (!keyInfo[3])
                  {
                    throw new InvalidKeyException(
                      "the certificate's key cannot be used for transforming data");
                  }
                if (keyInfo[7])
                  {
                    throw new InvalidKeyException(