Re: [v6ops] I-D Action: draft-ietf-6man-grand-01 - additional security concerns

Michael Richardson <mcr+ietf@sandelman.ca> Tue, 04 August 2020 00:04 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Tony Finch <dot@dotat.at>, v6ops list <v6ops@ietf.org>, 6man <ipv6@ietf.org>
Subject: Re: [v6ops] I-D Action: draft-ietf-6man-grand-01 - additional security concerns
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Date: Mon, 03 Aug 2020 20:04:18 -0400
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Tony Finch <dot@dotat.at> wrote:
    > Owen DeLong <owen@delong.com> wrote:
    >>
    >> Indeed, as an operator, IMHO, if there’s a place we need to focus on
    >> improving L2 attack surface in v6, it’s in finding better ways for
    >> {routers, hosts, switches} to mitigate/absorb this type of resource
    >> exhaustion attack. Unfortunately, this is a hard problem to solve, so we
    >> focus on moving the deck chairs we can move while ignoring the
    >> elephant-sized hole in the bulkheads that we don’t know how to patch.

    > If GRAND is deployed, would that allow routers to assume their neighbour
    > tables are complete, so they can just drop ND exhaustion attacks?

As said elsewhere in the thread, in general no.

Could a router develop heuristic in this direction that would help it protect
traffic during ND exhaustion attacks?  I think so.

Perhaps a signal from host to router in the ND that it does grand would be in order.

--
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-