Re: [secdir] SECDIR review of draft-ietf-xmpp-3921bis-15.txt

[Peter Saint-Andre <[e-mail]>]

Thanks for the review. One comment inline.

On 10/25/10 8:08 PM, Richard L. Barnes wrote:
> 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.
> 
> This document describes an instant-messaging and presence system based
> on the core system of exchanging XML stanzas described in RFC 3920 and
> draft-ietf-xmpp-3920bis.  As the document rightly notes, the underlying
> transport protocol addresses most of the security considerations for
> this document, and that document seems to have a thorough discussion of
> security considerations (although I have not done a thorough review). In
> general, I think that the security considerations in this document
> adequately describe the additional risks posed by the instant-messaging-
> and presence-specific parts of the protocol (beyond those of the base
> protocol), and corresponding mitigations.
> 
> One thing that might merit clarification: The overriding
> application-layer security concern here is the proper routing of
> presence and instant messaging stanzas through the XMPP system.
> (Underlying communications security concerns are addressed by the core
> spec.)  For the most part, these concerns with requirements on servers
> to act in certain ways on behalf of the user.  It could be helpful to
> the reader to re-state some of the communications patterns from Section
> 13.1 of draft-ietf-xmpp-3920bis and comment on the particular roles that
> the entities play in the context of instant messaging and presence
> (e.g., routing unicast <message> stanzas, fan-out of broadcast presence
> messages).

Although in general I'm not a fan of repeating material that is already
covered by a referenced specification, I agree that it might be
appropriate to provide a reminder about the underlying architecture of
XMPP and its implications for the security of various IM-related and
presence-related interactions. I'll reply again once I have investigated
the best location for such a reminder and have formulated proposed text.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/