Re: Q: Extract hardware address from received datagram?

From: Albrecht Dreß
Date: Mon Aug 15 2005 - 12:14:53 EST

Am 15.08.05 12:14 schrieb(en) Henrik Nordstrom:
Why is the link layer important at all in the protocol if the packet is an UDP/IP (PF_INET,SOCK_DGRAM) packet?

Due to this crazy protocol: the MAC addresses are used as some kind of "authentication". In the *reply* udp packet data, the micro adds its own mac and the mac of the requesting machine retreived from the incoming packet. The other end is a winbloze app which apparently uses the two mac's to determine whether the packet should be handles or not. It obvoisly had the same problems to determine the source mac, so it's encoded properly in the reply, but not in the request...

I know this protocol is really broken, but unfortunately I must keep compatibility. Sigh!

Thaks a lot for your suggestions,


Albrecht Dreß - Johanna-Kirchner-Straße 13 - D-53123 Bonn (Germany)
Phone (+49) 228 6199571 - mailto:albrecht.dress@xxxxxxxx
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