Re: [quicwg/base-drafts] handling of coalesced packets with decryption errors creates DoS opportunity (#2308)

Martin Thomson <notifications@github.com> Fri, 01 February 2019 01:51 UTC

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Subject: Re: [quicwg/base-drafts] handling of coalesced packets with decryption errors creates DoS opportunity (#2308)
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Yes, but @igorlord's point made me reconsider.  I think that the rule would need to be: a) senders MUST NOT coalesce packets of the same encryption level (there is no need to do so, so this is basically a no-op requirement); b) receivers SHOULD/MAY/MUST? discard packets if a packet of the same encryption level was received in the same datagram.  Unfortunately we can't do any more than this because an attacker has complete control over coalescing.

I realize now that this dovetails nicely with the requirement we already added here to require exactly one Retry or Version Negotiation in response to a packet.

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