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* accompanied this code).
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package com.sun.crypto.provider;
import java.io.UnsupportedEncodingException;
import java.security.*;
import java.security.spec.*;
import javax.crypto.*;
import javax.crypto.spec.*;
/**
* This class implements a proprietary password-based encryption algorithm.
* It is based on password-based encryption as defined by the PKCS #5
* standard, except that is uses triple DES instead of DES.
*
* Here's how this algorithm works:
*
* 1. Create random salt and split it in two halves. If the two halves are
* identical, invert one of them.
* 2. Concatenate password with each of the halves.
* 3. Digest each concatenation with c iterations, where c is the
* iterationCount. Concatenate the output from each digest round with the
* password, and use the result as the input to the next digest operation.
* The digest algorithm is MD5.
* 4. After c iterations, use the 2 resulting digests as follows:
* The 16 bytes of the first digest and the 1st 8 bytes of the 2nd digest
* form the triple DES key, and the last 8 bytes of the 2nd digest form the
* IV.
*
* @author Jan Luehe
* @see javax.crypto.Cipher
*/
public final class PBEWithMD5AndTripleDESCipher extends CipherSpi {
private PBES1Core core;
/**
* Creates an instance of this cipher, and initializes its mode (CBC) and
* padding (PKCS5).
*
* @exception NoSuchAlgorithmException if the required cipher mode (CBC) is
* unavailable
* @exception NoSuchPaddingException if the required padding mechanism
* (PKCS5Padding) is unavailable
*/
public PBEWithMD5AndTripleDESCipher()
throws NoSuchAlgorithmException, NoSuchPaddingException
{
// set the encapsulated cipher to do triple DES
core = new PBES1Core("DESede");
}
/**
* Sets the mode of this cipher. This algorithm can only be run in CBC
* mode.
*
* @param mode the cipher mode
*
* @exception NoSuchAlgorithmException if the requested cipher mode is
* invalid
*/
protected void engineSetMode(String mode) throws NoSuchAlgorithmException {
if ((mode != null) && (!mode.equalsIgnoreCase("CBC"))) {
throw new NoSuchAlgorithmException("Invalid cipher mode: " + mode);
}
}
/**
* Sets the padding mechanism of this cipher. This algorithm only uses
* PKCS #5 padding.
*
* @param padding the padding mechanism
*
* @exception NoSuchPaddingException if the requested padding mechanism
* is invalid
*/
protected void engineSetPadding(String paddingScheme)
throws NoSuchPaddingException
{
if ((paddingScheme != null) &&
(!paddingScheme.equalsIgnoreCase("PKCS5Padding"))) {
throw new NoSuchPaddingException("Invalid padding scheme: " +
paddingScheme);
}
}
/**
* Returns the block size (in bytes).
*
* @return the block size (in bytes)
*/
protected int engineGetBlockSize() {
return core.getBlockSize();
}
/**
* Returns the length in bytes that an output buffer would need to be in
* order to hold the result of the next <code>update</code> or
* <code>doFinal</code> operation, given the input length
* <code>inputLen</code> (in bytes).
*
* <p>This call takes into account any unprocessed (buffered) data from a
* previous <code>update</code> call, and padding.
*
* <p>The actual output length of the next <code>update</code> or
* <code>doFinal</code> call may be smaller than the length returned by
* this method.
*
* @param inputLen the input length (in bytes)
*
* @return the required output buffer size (in bytes)
*
*/
protected int engineGetOutputSize(int inputLen) {
return core.getOutputSize(inputLen);
}
/**
* Returns the initialization vector (IV) in a new buffer.
*
* <p> This is useful in the case where a random IV has been created
* (see <a href = "#init">init</a>),
* or in the context of password-based encryption or
* decryption, where the IV is derived from a user-supplied password.
*
* @return the initialization vector in a new buffer, or null if the
* underlying algorithm does not use an IV, or if the IV has not yet
* been set.
*/
protected byte[] engineGetIV() {
return core.getIV();
}
/**
* Returns the parameters used with this cipher.
*
* <p>The returned parameters may be the same that were used to initialize
* this cipher, or may contain the default set of parameters or a set of
* randomly generated parameters used by the underlying cipher
* implementation (provided that the underlying cipher implementation
* uses a default set of parameters or creates new parameters if it needs
* parameters but was not initialized with any).
*
* @return the parameters used with this cipher, or null if this cipher
* does not use any parameters.
*/
protected AlgorithmParameters engineGetParameters() {
return core.getParameters();
}
/**
* Initializes this cipher with a key and a source
* of randomness.
* The cipher is initialized for one of the following four operations:
* encryption, decryption, key wrapping or key unwrapping, depending on
* the value of <code>opmode</code>.
*
* <p>If this cipher (including its underlying feedback or padding scheme)
* requires any random bytes, it will get them from <code>random</code>.
*
* @param opmode the operation mode of this cipher (this is one of
* the following:
* <code>ENCRYPT_MODE</code>, <code>DECRYPT_MODE</code>),
* <code>WRAP_MODE</code> or <code>UNWRAP_MODE</code>)
* @param key the encryption key
* @param random the source of randomness
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this cipher
*/
protected void engineInit(int opmode, Key key, SecureRandom random)
throws InvalidKeyException {
try {
core.init(opmode, key, (AlgorithmParameterSpec) null, random);
} catch (InvalidAlgorithmParameterException ie) {
InvalidKeyException ike =
new InvalidKeyException("requires PBE parameters");
ike.initCause(ie);
throw ike;
}
}
/**
* Initializes this cipher with a key, a set of
* algorithm parameters, and a source of randomness.
* The cipher is initialized for encryption or decryption, depending on
* the value of <code>opmode</code>.
*
* <p>If this cipher (including its underlying feedback or padding scheme)
* requires any random bytes, it will get them from <code>random</code>.
*
* @param opmode the operation mode of this cipher (this is either
* <code>ENCRYPT_MODE</code> or <code>DECRYPT_MODE</code>)
* @param key the encryption key
* @param params the algorithm parameters
* @param random the source of randomness
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this cipher
* @exception InvalidAlgorithmParameterException if the given algorithm
* parameters are inappropriate for this cipher
*/
protected void engineInit(int opmode, Key key,
AlgorithmParameterSpec params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException {
core.init(opmode, key, params, random);
}
protected void engineInit(int opmode, Key key,
AlgorithmParameters params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException
{
core.init(opmode, key, params, random);
}
/**
* Continues a multiple-part encryption or decryption operation
* (depending on how this cipher was initialized), processing another data
* part.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, are processed, and the
* result is stored in a new buffer.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result
*
*/
protected byte[] engineUpdate(byte[] input, int inputOffset, int inputLen)
{
return core.update(input, inputOffset, inputLen);
}
/**
* Continues a multiple-part encryption or decryption operation
* (depending on how this cipher was initialized), processing another data
* part.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, are processed, and the
* result is stored in the <code>output</code> buffer, starting at
* <code>outputOffset</code>.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in <code>output</code> where the result
* is stored
*
* @return the number of bytes stored in <code>output</code>
*
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
*/
protected int engineUpdate(byte[] input, int inputOffset, int inputLen,
byte[] output, int outputOffset)
throws ShortBufferException
{
return core.update(input, inputOffset, inputLen,
output, outputOffset);
}
/**
* Encrypts or decrypts data in a single-part operation,
* or finishes a multiple-part operation.
* The data is encrypted or decrypted, depending on how this cipher was
* initialized.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, and any input bytes that
* may have been buffered during a previous <code>update</code> operation,
* are processed, with padding (if requested) being applied.
* The result is stored in a new buffer.
*
* <p>The cipher is reset to its initial state (uninitialized) after this
* call.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result
*
* @exception IllegalBlockSizeException if this cipher is a block cipher,
* no padding has been requested (only in encryption mode), and the total
* input length of the data processed by this cipher is not a multiple of
* block size
* @exception BadPaddingException if decrypting and padding is chosen,
* but the last input data does not have proper padding bytes.
*/
protected byte[] engineDoFinal(byte[] input, int inputOffset, int inputLen)
throws IllegalBlockSizeException, BadPaddingException
{
return core.doFinal(input, inputOffset, inputLen);
}
/**
* Encrypts or decrypts data in a single-part operation,
* or finishes a multiple-part operation.
* The data is encrypted or decrypted, depending on how this cipher was
* initialized.
*
* <p>The first <code>inputLen</code> bytes in the <code>input</code>
* buffer, starting at <code>inputOffset</code>, and any input bytes that
* may have been buffered during a previous <code>update</code> operation,
* are processed, with padding (if requested) being applied.
* The result is stored in the <code>output</code> buffer, starting at
* <code>outputOffset</code>.
*
* <p>The cipher is reset to its initial state (uninitialized) after this
* call.
*
* @param input the input buffer
* @param inputOffset the offset in <code>input</code> where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in <code>output</code> where the result
* is stored
*
* @return the number of bytes stored in <code>output</code>
*
* @exception IllegalBlockSizeException if this cipher is a block cipher,
* no padding has been requested (only in encryption mode), and the total
* input length of the data processed by this cipher is not a multiple of
* block size
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
* @exception BadPaddingException if decrypting and padding is chosen,
* but the last input data does not have proper padding bytes.
*/
protected int engineDoFinal(byte[] input, int inputOffset, int inputLen,
byte[] output, int outputOffset)
throws ShortBufferException, IllegalBlockSizeException,
BadPaddingException
{
return core.doFinal(input, inputOffset, inputLen,
output, outputOffset);
}
/**
* Returns the key size of the given key object.
*
* @param key the key object.
*
* @return the key size of the given key object.
*
* @exception InvalidKeyException if <code>key</code> is invalid.
*/
protected int engineGetKeySize(Key key) throws InvalidKeyException {
return 168;
}
/**
* Wrap a key.
*
* @param key the key to be wrapped.
*
* @return the wrapped key.
*
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