DESpublic class DES extends Cipher | Wrapper for all DES cipher classes. |
| Fields Summary |
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| Cipher | cipher |
| Constructors Summary |
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public DES()Public by name constructor.
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| Methods Summary |
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| public int | doFinal(byte[] input, int inputOffset, int inputLen, byte[] output, int 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.
The first inputLen bytes in the input
buffer, starting at inputOffset inclusive, and any input
bytes that may have been buffered during a previous
update operation, are processed, with padding
(if requested) being applied.
The result is stored in the output buffer, starting at
outputOffset inclusive.
If the output buffer is too small to hold the result,
a ShortBufferException is thrown. In this case, repeat this
call with a larger output buffer.
Upon finishing, this method resets this cipher object to the state
it was in when previously initialized via a call to init.
That is, the object is reset and available to encrypt or decrypt
(depending on the operation mode that was specified in the call to
init) more data.
Note: if any exception is thrown, this cipher object may need to
be reset before it can be used again.
Note: this method should be copy-safe, which means the
input and output buffers can reference
the same byte array and no unprocessed input data is overwritten
when the result is copied into the output buffer.
return cipher.doFinal(input, inputOffset, inputLen, output,
outputOffset);
| | public byte[] | getIV()Returns the initialization vector (IV) in a new buffer.
This is useful in the case where a random IV was created.
return cipher.getIV();
| | public void | init(int opmode, Key key, CryptoParameter params)Initializes this cipher with a key and a set of algorithm
parameters.
The cipher is initialized for one of the following operations:
encryption or decryption depending
on the value of opmode.
If this cipher requires any algorithm parameters and
params is null, the underlying cipher implementation is
supposed to generate the required parameters itself (using
provider-specific default or random values) if it is being
initialized for encryption, and raise an
InvalidAlgorithmParameterException if it is being
initialized for decryption.
Note that when a Cipher object is initialized, it loses all
previously-acquired state. In other words, initializing a Cipher is
equivalent to creating a new instance of that Cipher and initializing
it.
cipher.init(opmode, key, params);
| | protected void | setChainingModeAndPadding(java.lang.String mode, java.lang.String padding)Called by the factory method to set the mode and padding parameters.
Need because Class.newInstance does not take args.
if (mode.equals("ECB") || mode.equals("")) {
cipher = new DES_ECB(false);
} else if (mode.equals("CBC")) {
cipher = new DES_CBC(false);
} else {
throw new IllegalArgumentException();
}
cipher.setChainingModeAndPadding(mode, padding);
| | public int | update(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)Continues a multiple-part encryption or decryption operation
(depending on how this cipher was initialized), processing another data
part.
The first inputLen bytes in the input
buffer, starting at inputOffset inclusive, are processed,
and the result is stored in the output buffer, starting at
outputOffset inclusive.
If the output buffer is too small to hold the result,
a ShortBufferException is thrown. In this case, repeat this
call with a larger output buffer.
If inputLen is zero, this method returns
a length of zero.
Note: this method should be copy-safe, which means the
input and output buffers can reference
the same byte array and no unprocessed input data is overwritten
when the result is copied into the output buffer.
return cipher.update(input, inputOffset, inputLen, output,
outputOffset);
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