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Wireshark-dev: [Wireshark-dev] SCTP TSN analysis: gap acks not working

From: Jeff Morriss <jeff.morriss@xxxxxxxxxxx>
Date: Thu, 01 Mar 2007 17:25:39 +0800

Hi Luis,

First, thank you so much for your work on the TSN analysis in SCTP! It's something I've wanted to do for a long time...

Anyway, with the latest change, gap acks aren't working. I've narrowed it down to this section of code:

        if (t = emem_tree_lookup32(h->peer->tsn_acks, framenum)) {
                for(;t;t = t->next) {
                        ack_tree(t, acks_tree, tvb, pinfo);
                }

                return;
        }

which has the 2nd call into that function ('sctp_ack_block()') for a SACK with gap acks returning there. It looks to me like the check for duplicate SACKs needs to include the TSN number or else the gap ack processing needs to be pulled (back) out into a separate function.

I can look at how to fix it but I wasn't sure if you're still actively working in the area and don't want to step on your toes.

-J