Class GCMBlockCipher

    • 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 params)
                  throws IllegalArgumentException
        NOTE: MAC sizes from 32 bits to 128 bits (must be a multiple of 8) are supported. The default is 128 bits. Sizes less than 96 are not recommended, but are supported for specialized applications.
        Specified by:
        init in interface AEADCipher
        Parameters:
        forEncryption - true if we are setting up for encryption, false otherwise.
        params - the necessary parameters for the underlying cipher to be initialised.
        Throws:
        IllegalArgumentException - if the params argument is inappropriate.
      • 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 in)
        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:
        in - the byte to be processed.
      • processAADBytes

        public void processAADBytes​(byte[] in,
                                    int inOff,
                                    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:
        in - 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.
      • processByte

        public int processByte​(byte in,
                               byte[] out,
                               int outOff)
                        throws DataLengthException
        Description copied from interface: AEADCipher
        encrypt/decrypt a single byte.
        Specified by:
        processByte in interface AEADCipher
        Parameters:
        in - the byte to be processed.
        out - 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[] in,
                                int inOff,
                                int len,
                                byte[] out,
                                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:
        in - 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.
        out - 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