In message <[email protected]>, Mike Silbersack writes: > >On Tue, 20 Apr 2004, Don Lewis wrote: > >> I am concerned that step C will not solve the compatibility problem. The >> FreeBSD host is sending a FIN to close an established connection, and >> the peer host adding the window size advertised in the FIN packet to the >> sequence number acknowledged in the FIN packet, and using the sum as the >> sequence number for the RST packet, which puts the sequence number at >> the end of the receive window. > >Would it be feasible for us to create a four to five element array to >track "resettable" sequence numbers? This could hold the sequence numbers >of the last few packets transmitted, and account for that edge case as >well. Sounds like an interesting idea. Technically you will have to hold the sequence numbers for all non-ACK'ed packets, which may be up to the window divided by the MTU. In the conventional case, worst case is 237 sequence numbers (65535/276). This sounds like a lot until one realizes that at the same time we hold 64k of un-ACK'ed data. A prototype would be a good thing... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [email protected] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "[email protected]"