Package org.bouncycastle.crypto.modes

Class CBCBlockCipher

  • All Implemented Interfaces:
    BlockCipher
    public class CBCBlockCipher
extends java.lang.Object
implements BlockCipher
    implements Cipher-Block-Chaining (CBC) mode on top of a simple cipher.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.String getAlgorithmName()
      return the algorithm name and mode.
      int getBlockSize()
      return the block size of the underlying cipher.
      BlockCipher getUnderlyingCipher()
      return the underlying block cipher that we are wrapping.
      void init​(boolean encrypting, CipherParameters params)
      Initialise the cipher and, possibly, the initialisation vector (IV).
      int processBlock​(byte[] in, int inOff, byte[] out, int outOff)
      Process one block of input from the array in and write it to the out array.
      void reset()
      reset the chaining vector back to the IV and reset the underlying cipher.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • CBCBlockCipher

        public CBCBlockCipher​(BlockCipher cipher)
        Basic constructor.
        Parameters:
        cipher - the block cipher to be used as the basis of chaining.

    • Method Detail

      • getUnderlyingCipher

        public BlockCipher getUnderlyingCipher()
        return the underlying block cipher that we are wrapping.
        Returns:
        the underlying block cipher that we are wrapping.

      • init

        public void init​(boolean encrypting,
                 CipherParameters params)
          throws java.lang.IllegalArgumentException
        Initialise the cipher and, possibly, the initialisation vector (IV). If an IV isn't passed as part of the parameter, the IV will be all zeros.
        Specified by:
        init in interface BlockCipher
        Parameters:
        encrypting - if true the cipher is initialised for encryption, if false for decryption.
        params - the key and other data required by the cipher.
        Throws:
        java.lang.IllegalArgumentException - if the params argument is inappropriate.

      • getAlgorithmName

        public java.lang.String getAlgorithmName()
        return the algorithm name and mode.
        Specified by:
        getAlgorithmName in interface BlockCipher
        Returns:
        the name of the underlying algorithm followed by "/CBC".

      • getBlockSize

        public int getBlockSize()
        return the block size of the underlying cipher.
        Specified by:
        getBlockSize in interface BlockCipher
        Returns:
        the block size of the underlying cipher.

      • processBlock

        public int processBlock​(byte[] in,
                        int inOff,
                        byte[] out,
                        int outOff)
                 throws DataLengthException,
                        java.lang.IllegalStateException
        Process one block of input from the array in and write it to the out array.
        Specified by:
        processBlock in interface BlockCipher
        Parameters:
        in - the array containing the input data.
        inOff - offset into the in array the data starts at.
        out - the array the output data will be copied into.
        outOff - the offset into the out array the output will start at.
        Returns:
        the number of bytes processed and produced.
        Throws:
        DataLengthException - if there isn't enough data in in, or space in out.
        java.lang.IllegalStateException - if the cipher isn't initialised.

      • reset

        public void reset()
        reset the chaining vector back to the IV and reset the underlying cipher.
        Specified by:
        reset in interface BlockCipher