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The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.4.
package org.bouncycastle.crypto.modes;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.DataLengthException;
import org.bouncycastle.crypto.InvalidCipherTextException;
/**
* A cipher mode that includes authenticated encryption with a streaming mode and optional associated data.
*
* Implementations of this interface may operate in a packet mode (where all input data is buffered and
* processed during the call to {@link #doFinal(byte[], int)}), or in a streaming mode (where output data is
* incrementally produced with each call to {@link #processByte(byte, byte[], int)} or
* {@link #processBytes(byte[], int, int, byte[], int)}.
*
* This is important to consider during decryption: in a streaming mode, unauthenticated plaintext data
* may be output prior to the call to {@link #doFinal(byte[], int)} that results in an authentication
* failure. The higher level protocol utilising this cipher must ensure the plaintext data is handled
* appropriately until the end of data is reached and the entire ciphertext is authenticated.
* @see org.bouncycastle.crypto.params.AEADParameters
*/
public interface AEADCipher
{
/**
* initialise the underlying cipher. Parameter can either be an AEADParameters or a ParametersWithIV object.
*
* @param forEncryption true if we are setting up for encryption, false otherwise.
* @param params the necessary parameters for the underlying cipher to be initialised.
* @exception IllegalArgumentException if the params argument is inappropriate.
*/
public void init(boolean forEncryption, CipherParameters params)
throws IllegalArgumentException;
/**
* Return the name of the algorithm.
*
* @return the algorithm name.
*/
public String getAlgorithmName();
/**
* Add a single byte to the associated data check.
* If the implementation supports it, this will be an online operation and will not retain the associated data.
*
* @param in the byte to be processed.
*/
public void processAADByte(byte in);
/**
* Add a sequence of bytes to the associated data check.
* If the implementation supports it, this will be an online operation and will not retain the associated data.
*
* @param in the input byte array.
* @param inOff the offset into the in array where the data to be processed starts.
* @param len the number of bytes to be processed.
*/
public void processAADBytes(byte[] in, int inOff, int len);
/**
* encrypt/decrypt a single byte.
*
* @param in the byte to be processed.
* @param out the output buffer the processed byte goes into.
* @param outOff the offset into the output byte array the processed data starts at.
* @return the number of bytes written to out.
* @exception DataLengthException if the output buffer is too small.
*/
public int processByte(byte in, byte[] out, int outOff)
throws DataLengthException;
/**
* process a block of bytes from in putting the result into out.
*
* @param in the input byte array.
* @param inOff the offset into the in array where the data to be processed starts.
* @param len the number of bytes to be processed.
* @param out the output buffer the processed bytes go into.
* @param outOff the offset into the output byte array the processed data starts at.
* @return the number of bytes written to out.
* @exception DataLengthException if the output buffer is too small.
*/
public int processBytes(byte[] in, int inOff, int len, byte[] out, int outOff)
throws DataLengthException;
/**
* Finish the operation either appending or verifying the MAC at the end of the data.
*
* @param out space for any resulting output data.
* @param outOff offset into out to start copying the data at.
* @return number of bytes written into out.
* @throws IllegalStateException if the cipher is in an inappropriate state.
* @throws org.bouncycastle.crypto.InvalidCipherTextException if the MAC fails to match.
*/
public int doFinal(byte[] out, int outOff)
throws IllegalStateException, InvalidCipherTextException;
/**
* Return the value of the MAC associated with the last stream processed.
*
* @return MAC for plaintext data.
*/
public byte[] getMac();
/**
* return the size of the output buffer required for a processBytes
* an input of len bytes.
*
* The returned size may be dependent on the initialisation of this cipher
* and may not be accurate once subsequent input data is processed - this method
* should be invoked immediately prior to input data being processed.
*
*
* @param len the length of the input.
* @return the space required to accommodate a call to processBytes
* with len bytes of input.
*/
public int getUpdateOutputSize(int len);
/**
* return the size of the output buffer required for a processBytes plus a
* doFinal with an input of len bytes.
*
* The returned size may be dependent on the initialisation of this cipher
* and may not be accurate once subsequent input data is processed - this method
* should be invoked immediately prior to a call to final processing of input data
* and a call to {@link #doFinal(byte[], int)}.
*
* @param len the length of the input.
* @return the space required to accommodate a call to processBytes and doFinal
* with len bytes of input.
*/
public int getOutputSize(int len);
/**
* Reset the cipher. After resetting the cipher is in the same state
* as it was after the last init (if there was one).
*/
public void reset();
}