crypto_arcfour_crypt
static int crypto_arcfour_crypt(ARCFour_key *, uchar_t *, crypto_data_t *,
ret = crypto_arcfour_crypt(key, (uchar_t *)start, output,
ret = crypto_arcfour_crypt(key, start, output,
ret = crypto_arcfour_crypt(key, start, output,
ret = crypto_arcfour_crypt(key, start + offset,