cbc_crypt
int cbc_crypt( char *, char *, unsigned int, unsigned int, char *);
status = cbc_crypt((char *)&auth->ah_key, (char *)cryptbuf,
status = cbc_crypt((char *)sessionkey, (char *)cryptbuf,
err = cbc_crypt(key, buf, len, DES_DECRYPT | DES_HW, ivec);
err = cbc_crypt(key, buf, len, DES_ENCRYPT | DES_HW, ivec);