netdev - Re: [PATCH 3/3] [RFC] TCP syncookies: only allow 3 MSS values by default to mitigate spoofing attacks

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Message-ID: <20130816213101.GD5154@breakpoint.cc>
Date:	Fri, 16 Aug 2013 23:31:01 +0200
From:	Florian Westphal <fw@...len.de>
To:	Jiri Bohac <jbohac@...e.cz>
Cc:	Jakob Lell <jakob@...oblell.com>, netdev@...r.kernel.org,
	davem@...emloft.net
Subject: Re: [PATCH 3/3] [RFC] TCP syncookies: only allow 3 MSS values by
 default to mitigate spoofing attacks

Jiri Bohac <jbohac@...e.cz> wrote:
> Rationale for the new values
> - most packets are (1500 - headers); (1450 - headers) is not a huge waste and
>   prevents fallback to much lower values

Still, 1410 seems weird.

> - clients will rarely send MSS below 536, so that's a safe fallback

Can you elaborate?
You say 'is a safe fallback', yet it is removed in the patch?

> - we need to keep the minimum (64)

Why?
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