Re: help with packet tracer

[Gisle Vanem <gvanem () broadpark no>]

> the size of the Ip works, but when I get the tcp packet, things don't work 
> as planned--it gives invalid ports.

I see:

 tcp = (tcp_hdr *) ((packet + sizeof (ether_hdr)) + ip_size);
 cout << "Source port: " << tcp->th_sport << "\t\tDestination port: " << tcp->th_dport << "." << endl;

You forgot to use ntohs(). These are 16-bit on network order.

--gv

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