[secdir] secdir review of draft-ietf-tcpm-tcpmss-04

Klaas Wierenga <klaas@cisco.com> Wed, 30 May 2012 15:05 UTC

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Date: Wed, 30 May 2012 17:05:21 +0200
From: Klaas Wierenga <klaas@cisco.com>
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Subject: [secdir] secdir review of draft-ietf-tcpm-tcpmss-04
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Hi,

I have reviewed this document as part of the security directorate's
ongoing effort to review all IETF documents being processed by the
IESG.  These comments were written primarily for the benefit of the
security area directors.  Document editors and WG chairs should treat
these comments just like any other last call comments.

General comments:
==================

This is a short, clear and to the point draft. I have only a few
general comments

1 (introduction)
- ----------------

- - Please expand MSS on first use

- - "(see appendix A)" and "but there still seems to be some confusion"

This sounds pretty vague to me. I thought Appendix A would be a
verbatim copy of the text from 1122, but it is much more, and I
appreciated the discussion. I propose to make that explicit:

"RFC1122 clarified the MSS option, but confusion remains as discussed
in Appendix A"

Security Considerations:
========================
I don't really think what you have written down here qualifies as
security considerations. It sort of hints to a denial-of-service, but
I don't see any evil, just an operational problem. What I wonder about
(but I am not knowledgable to judge) is whether wrong MSS size
settings could be exploited for for example buffer overflow attacks.


Cheers,

Klaas
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