org.bouncycastle.crypto
public class BufferedBlockCipher extends Object
Note: in the case where the underlying cipher is either a CFB cipher or an OFB one the last block may not be a multiple of the block size.
Field Summary | |
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protected byte[] | buf |
protected int | bufOff |
protected BlockCipher | cipher |
protected boolean | forEncryption |
protected boolean | partialBlockOkay |
protected boolean | pgpCFB |
Constructor Summary | |
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protected | BufferedBlockCipher()
constructor for subclasses |
BufferedBlockCipher(BlockCipher cipher)
Create a buffered block cipher without padding.
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Method Summary | |
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int | doFinal(byte[] out, int outOff)
Process the last block in the buffer.
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int | getBlockSize()
return the blocksize for the underlying cipher.
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int | getOutputSize(int len)
return the size of the output buffer required for an update plus a
doFinal with an input of len bytes.
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BlockCipher | getUnderlyingCipher()
return the cipher this object wraps.
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int | getUpdateOutputSize(int len)
return the size of the output buffer required for an update
an input of len bytes.
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void | init(boolean forEncryption, CipherParameters params)
initialise the cipher.
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int | processByte(byte in, byte[] out, int outOff)
process a single byte, producing an output block if neccessary.
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int | processBytes(byte[] in, int inOff, int len, byte[] out, int outOff)
process an array of bytes, producing output if necessary.
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void | reset()
Reset the buffer and cipher. |
Parameters: cipher the underlying block cipher this buffering object wraps.
Parameters: out the array the block currently being held is copied into. outOff the offset at which the copying starts.
Returns: the number of output bytes copied to out.
Throws: DataLengthException if there is insufficient space in out for the output, or the input is not block size aligned and should be. IllegalStateException if the underlying cipher is not initialised. InvalidCipherTextException if padding is expected and not found. DataLengthException if the input is not block size aligned.
Returns: the blocksize for the underlying cipher.
Parameters: len the length of the input.
Returns: the space required to accommodate a call to update and doFinal with len bytes of input.
Returns: the cipher this object wraps.
Parameters: len the length of the input.
Returns: the space required to accommodate a call to update with len bytes of input.
Parameters: forEncryption if true the cipher is initialised for encryption, if false for decryption. params the key and other data required by the cipher.
Throws: IllegalArgumentException if the params argument is inappropriate.
Parameters: in the input byte. out the space for any output that might be produced. outOff the offset from which the output will be copied.
Returns: the number of output bytes copied to out.
Throws: DataLengthException if there isn't enough space in out. IllegalStateException if the cipher isn't initialised.
Parameters: in the input byte array. inOff the offset at which the input data starts. len the number of bytes to be copied out of the input array. out the space for any output that might be produced. outOff the offset from which the output will be copied.
Returns: the number of output bytes copied to out.
Throws: DataLengthException if there isn't enough space in out. IllegalStateException if the cipher isn't initialised.