Re: [secdir] pana-relay security considerations

Alan DeKok <aland@deployingradius.com> Mon, 10 January 2011 11:00 UTC

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Date: Mon, 10 Jan 2011 12:02:42 +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:
> The PaC picks an ephemeral port when sending the PANA packet. Src:any, dst:
> 716. And the response from the PAA reverses the ports. 

  OK.

> The most PRE can do is to check if source port is 716.
> 
> If the PRE knows that it received the packet from a trusted source (by means
> of DTLS, physical security, IPsec, etc.), then the PRE should not
> normally(*) have to perform another level of check on the packets. 

  And if not?  Anyone can pretend to be the PAA, and send any data to
any port on the PaC.  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.

  Alan DeKok.