Re: [quicwg/base-drafts] Remove PATH_RESPONSE limits (#2241)

MikkelFJ <notifications@github.com> Fri, 21 December 2018 20:53 UTC

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Subject: Re: [quicwg/base-drafts] Remove PATH_RESPONSE limits (#2241)
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> @mikkelfj: how can this lead to amplification?

If an endpoint seeing a challenge uses the opportunity to discover if its preferred MTU is supported by padding the response (as opposed to the challenge) even if the challenge packet is small. Since this might fail, it like will also send a small response after a delay or after a new challenge if it doesn't get an ACK before that.

A defence could be to ensure that challenges are no larger than, say twice, response.

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