rc4_crypt
extern void rc4_crypt(struct rc4_state *state,
rc4_crypt(&d->rc4, outbuf + MPPC_HDRLEN,
rc4_crypt(&d->rc4, buf, buf, len);
rc4_crypt(rc4, key, key, keylen);
rc4_crypt(&d->rc4, mtod(m1, u_char *),
rc4_crypt(&d->rc4, mtod(m1, u_char *),
rc4_crypt(rc4, key, key, keylen);