* \brief encrypt a block with the CAST-5 algorithm
*
* This function encrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
* It uses a keyschedule as generated by the
* \brief encrypt a block with the CAST-5 algorithm
*
* This function encrypts a block of 64 bits (8 bytes) with the CAST-5 algorithm.
* It uses a keyschedule as generated by the