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From: "İbrahim Ercan" <ibrahim.metu@gmail.com>
To: Florian Westphal <fw@strlen.de>
Cc: netfilter@vger.kernel.org, netfilter-devel@vger.kernel.org
Subject: Re: Is this possible SYN Proxy bug?
Date: Tue, 18 Jun 2019 14:40:34 +0300	[thread overview]
Message-ID: <CAK6Qs9kmxqOaCjgcBefPR-NKEdGKTcfKUL_tu09CQYp3OT5krA@mail.gmail.com> (raw)
In-Reply-To: <20190618104041.unuonhmuvgnlty3l@breakpoint.cc>

On Tue, Jun 18, 2019 at 1:40 PM Florian Westphal <fw@strlen.de> wrote:
>
> Problem is that we do not keep any state.  Syncookes are restricted to 4
> mss value:
> static __u16 const msstab[] = {
>  536,
> 1300,
> 1440,   /* 1440, 1452: PPPoE */
> 1460,
> };
>
> So, 1260 forces lowest value supported.
>
> The table was based off a research paper that had mss distribution
> tables.  Maybe more recent data is available and if things have changed
> we could update the table accordingly.

I am confused. So this statement from manual page is just a illusion?
--mss maximum segment size
              Maximum segment size announced to clients. This must
match the backend.

I don't understand why these restriction exist. Why can't we set mss
value same as what client send to us?

  reply	other threads:[~2019-06-18 11:40 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-18 10:06 Is this possible SYN Proxy bug? İbrahim Ercan
2019-06-18 10:40 ` Florian Westphal
2019-06-18 11:40   ` İbrahim Ercan [this message]
2019-06-18 11:59     ` Florian Westphal
2019-06-18 12:07       ` İbrahim Ercan
2019-06-18 12:40         ` Florian Westphal
2019-06-19  9:26           ` İbrahim Ercan
2019-06-21  7:00             ` İbrahim Ercan
2019-06-21 11:10               ` Florian Westphal
2019-06-24  7:55                 ` İbrahim Ercan
2019-06-24  8:09                   ` Fernando Fernandez Mancera
2019-06-24 10:20                   ` Florian Westphal
2019-06-24 12:35                     ` İbrahim Ercan
2019-06-24 13:32                       ` Florian Westphal
     [not found]   ` <OFD1A8080A.6956CA33-ON0025841D.003AFD98-C125841D.003BC900@notes.na.collabserv.com>
2019-06-18 11:50     ` İbrahim Ercan

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