Re: [quicwg/base-drafts] Disallow reuse of stateless reset tokens (#2785)

Marten Seemann <notifications@github.com> Thu, 13 June 2019 01:46 UTC

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Subject: Re: [quicwg/base-drafts] Disallow reuse of stateless reset tokens (#2785)
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I agree that we should remove the text that allows the reuse of SRTs from the spec (In fact, last night I was planning to open exactly this issue, and woke up this morning to see that @DavidSchinazi already did so while I was asleep).

I don’t see any reason why you’d want to reuse a SRT in the first place - computing one HMAC shouldn’t be more expensive than applying the packe protection to send a single packet. With regards to how you store connection IDS, this design is only simpler if you do the wrong thing and don‘t keep track of expired connection IDs that still have active SRTs. Doing it the right way will most likely result in a more complex design than associating each CID with its own SRT.

In short: it’s easy to mess up, and there’s little benefit, so let’s remove it. 

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