+/** \fn void noekeon_enc(void* buffer, void* key)
+ * \brief noekeon encrytion funtion
+ *
+ * This function encrypts a block (64 bit = 8 byte) with the noekeon encrytion
+ * algorithm. Due to the two modes of noekeon (direct mode and indirect mode)
+ * the second parameter either points directly to the key (direct mode) or to a
+ * context generated by the noekeon_init() function (indirect mode)
+ * \param buffer pointer to the 64 bit (8 byte) block to encrypt
+ * \param key pointer to either the key (128 bit = 16 byte; direct mode) or
+ * to the context (indirect mode)
+ */