Re: [secdir] SecDir review of draft-ietf-avt-rtcp-port-for-ssm-03

"Ali C. Begen (abegen)" <> Wed, 15 December 2010 04:51 UTC

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Date: Tue, 14 Dec 2010 20:52:33 -0800
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Thread-Topic: SecDir review of draft-ietf-avt-rtcp-port-for-ssm-03
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From: "Ali C. Begen (abegen)" <>
To: "Donald Eastlake" <>, <>, <>, "Keith Drage" <>, "Roni Even" <>
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Subject: Re: [secdir] SecDir review of draft-ietf-avt-rtcp-port-for-ssm-03
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Hi Donald,

Thanks for the review.

> -----Original Message-----
> From: Donald Eastlake []
> Sent: Tuesday, December 14, 2010 10:47 PM
> To:;; Ali C. Begen (abegen); Keith Drage; Roni Even
> Subject: SecDir review of draft-ietf-avt-rtcp-port-for-ssm-03
> I have reviewed this document as part of the security directorate's
> ongoing effort to review all IETF documents being processed by the
> IESG.  Document editors and WG chairs should treat these comments just
> like any other last call comments.
> This draft specifies the addition of a new SDP attribute. This
> attribute does not appear to present any new type of security
> vulnerability.
> I believe the Security Considerations section needs a small addition
> to avoid being too vague. It currently just says "Therefore, as usual
> adequate security measures are RECOMMENDED ..." without giving any
> hint as to what those measures are or where to find any. Admittedly,
> this draft is an update to RFC 5760 and a reasonable non-exclusive
> list of such measures occurs in that RFC. Nevertheless, I would be
> much more comfortable if the Security Considerations section wording
> was augmented so it said "Therefore, adequate security measures, such
> as those listed in the Security Considerations section of [RFC5760],
> are RECOMMENDED...".

Based on other reviews and discussing with the AD, we went one step further and the sentence above is replaced with:
"In order to avoid attacks of this sort, the SDP description needs to be integrity protected and provided with source authentication. This can, for example, be achieved on an end-to-end basis using S/MIME RFC5652 when SDP is used in a signaling packet using MIME types (application/sdp). Alternatively, HTTPS RFC2818 or the authentication method in the Session Announcement Protocol (SAP) RFC2974 could be used as well."

> Trivia:
> The following sentence:
>    "The formal description of the 'multicast-rtcp' attribute is defined
>    by the following ABNF [RFC5234] syntax:"
> somehow reads as sort of redundantly redundant. Maybe: "The following
> ABNF [RFC5234] syntax formally describes the 'multicast-rtcp'
> attribute:"

Sounds good.

Cheers, acbegen.
> Thanks,
> Donald
> =============================
>  Donald E. Eastlake 3rd   +1-508-333-2270 (cell)