Class OCBBlockCipher

    • Method Detail

      • getAlgorithmName

        public String getAlgorithmName()
        Description copied from interface: AEADCipher
        Return the name of the algorithm.
        Specified by:
        getAlgorithmName in interface AEADCipher
        Returns:
        the algorithm name.
      • init

        public void init​(boolean forEncryption,
                         CipherParameters parameters)
                  throws IllegalArgumentException
        Description copied from interface: AEADCipher
        initialise the underlying cipher. Parameter can either be an AEADParameters or a ParametersWithIV object.
        Specified by:
        init in interface AEADCipher
        Parameters:
        forEncryption - true if we are setting up for encryption, false otherwise.
        parameters - the necessary parameters for the underlying cipher to be initialised.
        Throws:
        IllegalArgumentException - if the params argument is inappropriate.
      • processNonce

        protected int processNonce​(byte[] N)
      • getMac

        public byte[] getMac()
        Description copied from interface: AEADCipher
        Return the value of the MAC associated with the last stream processed.
        Specified by:
        getMac in interface AEADCipher
        Returns:
        MAC for plaintext data.
      • getOutputSize

        public int getOutputSize​(int len)
        Description copied from interface: AEADCipher
        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 AEADCipher.doFinal(byte[], int).

        Specified by:
        getOutputSize in interface AEADCipher
        Parameters:
        len - the length of the input.
        Returns:
        the space required to accommodate a call to processBytes and doFinal with len bytes of input.
      • getUpdateOutputSize

        public int getUpdateOutputSize​(int len)
        Description copied from interface: AEADCipher
        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.

        Specified by:
        getUpdateOutputSize in interface AEADCipher
        Parameters:
        len - the length of the input.
        Returns:
        the space required to accommodate a call to processBytes with len bytes of input.
      • processAADByte

        public void processAADByte​(byte input)
        Description copied from interface: AEADCipher
        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.
        Specified by:
        processAADByte in interface AEADCipher
        Parameters:
        input - the byte to be processed.
      • processAADBytes

        public void processAADBytes​(byte[] input,
                                    int off,
                                    int len)
        Description copied from interface: AEADCipher
        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.
        Specified by:
        processAADBytes in interface AEADCipher
        Parameters:
        input - the input byte array.
        off - the offset into the in array where the data to be processed starts.
        len - the number of bytes to be processed.
      • processByte

        public int processByte​(byte input,
                               byte[] output,
                               int outOff)
                        throws DataLengthException
        Description copied from interface: AEADCipher
        encrypt/decrypt a single byte.
        Specified by:
        processByte in interface AEADCipher
        Parameters:
        input - the byte to be processed.
        output - the output buffer the processed byte goes into.
        outOff - the offset into the output byte array the processed data starts at.
        Returns:
        the number of bytes written to out.
        Throws:
        DataLengthException - if the output buffer is too small.
      • processBytes

        public int processBytes​(byte[] input,
                                int inOff,
                                int len,
                                byte[] output,
                                int outOff)
                         throws DataLengthException
        Description copied from interface: AEADCipher
        process a block of bytes from in putting the result into out.
        Specified by:
        processBytes in interface AEADCipher
        Parameters:
        input - the input byte array.
        inOff - the offset into the in array where the data to be processed starts.
        len - the number of bytes to be processed.
        output - the output buffer the processed bytes go into.
        outOff - the offset into the output byte array the processed data starts at.
        Returns:
        the number of bytes written to out.
        Throws:
        DataLengthException - if the output buffer is too small.
      • reset

        public void reset()
        Description copied from interface: AEADCipher
        Reset the cipher. After resetting the cipher is in the same state as it was after the last init (if there was one).
        Specified by:
        reset in interface AEADCipher
      • clear

        protected void clear​(byte[] bs)
      • getLSub

        protected byte[] getLSub​(int n)
      • processHashBlock

        protected void processHashBlock()
      • processMainBlock

        protected void processMainBlock​(byte[] output,
                                        int outOff)
      • reset

        protected void reset​(boolean clearMac)
      • updateHASH

        protected void updateHASH​(byte[] LSub)
      • OCB_double

        protected static byte[] OCB_double​(byte[] block)
      • OCB_extend

        protected static void OCB_extend​(byte[] block,
                                         int pos)
      • OCB_ntz

        protected static int OCB_ntz​(long x)
      • shiftLeft

        protected static int shiftLeft​(byte[] block,
                                       byte[] output)
      • xor

        protected static void xor​(byte[] block,
                                  byte[] val)