Package org.bouncycastle.crypto.modes

Class CBCBlockCipher

java.lang.Object
org.bouncycastle.crypto.DefaultMultiBlockCipher
org.bouncycastle.crypto.modes.CBCBlockCipher
All Implemented Interfaces:
BlockCipher, CBCModeCipher, MultiBlockCipher
public class CBCBlockCipher extends DefaultMultiBlockCipher implements CBCModeCipher
implements Cipher-Block-Chaining (CBC) mode on top of a simple cipher.

  • Constructor Details

    • CBCBlockCipher

      public CBCBlockCipher(BlockCipher cipher)
      Deprecated.
      use the CBCBlockCipher.newInstance() static method.
      Basic constructor.
      Parameters:
      cipher - the block cipher to be used as the basis of chaining.

  • Method Details

    • newInstance

      public static CBCModeCipher newInstance(BlockCipher cipher)
      Return a new CBC mode cipher based on the passed in base cipher
      Parameters:
      cipher - the base cipher for the CBC mode.

    • getUnderlyingCipher

      public BlockCipher getUnderlyingCipher()
      return the underlying block cipher that we are wrapping.
      Specified by:
      getUnderlyingCipher in interface CBCModeCipher
      Returns:
      the underlying block cipher that we are wrapping.

    • init

      public void init(boolean encrypting, CipherParameters params) throws 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:
      IllegalArgumentException - if the params argument is inappropriate.

    • getAlgorithmName

      public 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, 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.
      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