Re: [secdir] pana-relay security considerations

Alan DeKok <aland@deployingradius.com> Mon, 10 January 2011 12:04 UTC

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Date: Mon, 10 Jan 2011 13:06:52 +0100
From: Alan DeKok <aland@deployingradius.com>
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To: Alper Yegin <alper.yegin@yegin.org>
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Cc: secdir@ietf.org, paduffy@cisco.com, margaretw42@gmail.com, pana@ietf.org, robert.cragie@gridmerge.com, samitac@ipinfusion.com, 'Ralph Droms' <rdroms.ietf@gmail.com>
Subject: Re: [secdir] pana-relay security considerations
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Alper Yegin wrote:
> PRE would authenticate and authorize the other end-point who claims to be a
> legit PAA before accepting any packets from it. So, it's not  "anyone".

  Only when a secure transport is used.  When a secure transport is not
used, the PAA to PRE is just UDP, which is spoofable.

>> If this data MUST be a well-formed PANA packet,
>> the security issues are minimal.  But I don't see that requirement
>> clearly in the document.
> 
> This is the DPI aspect. 

  The PRE can't verify that it's sending a valid PANA packet to the PaC?

> What should we check for well-formation? Many if not all fields in the PANA
> header may be updated by future releases of the spec (extensions, etc.). so
> checking on them would force the PRE to get upgraded (with a revised version
> of PANA-relay spec each time) when PaC/PAA gets upgraded. This is very
> undesirable. 

  Some basic level of checks should be possible.

> I think we shall stick to relying on PAA-PRE security.

  Then it should be a MUST.

  Alan DeKok.