Date: Tue, 06 Jun 2017 23:46:53 -0700
From: MikkelFJ <notifications@github.com>
Reply-To: quicwg/base-drafts
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Message-ID: <quicwg/base-drafts/issues/597/306702712@github.com>
In-Reply-To: <quicwg/base-drafts/issues/597@github.com>
References: <quicwg/base-drafts/issues/597@github.com>
Subject: Re: [quicwg/base-drafts] Connection abort during handshake (#597)
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>Well thats why I think this is another reason for using Server Stateless Retry, which returns client's selected random packet number and can be validated by client. It would be hard for attacker to guess that value (2^31).

On using packet numbers for validation: I think it would be simpler to validate on a client and a server chosen nonce (aka Connection Id) because it requires less state, but I might be missing something. For example if failing on a second Client ClearText packet you need to remember all packet numbers and while retransmission does this, it is a different machinery. Having the nonces also simplifies state lookup.

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<blockquote>
<p>Well thats why I think this is another reason for using Server Stateless=
 Retry, which returns client's selected random packet number and can be val=
idated by client. It would be hard for attacker to guess that value (2^31).=
</p>
</blockquote>
<p>On using packet numbers for validation: I think it would be simpler to v=
alidate on a client and a server chosen nonce (aka Connection Id) because i=
t requires less state, but I might be missing something. For example if fai=
ling on a second Client ClearText packet you need to remember all packet nu=
mbers and while retransmission does this, it is a different machinery. Havi=
ng the nonces also simplifies state lookup.</p>

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 using packet numbers for validation: I think it would be simpler to valida=
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uires less state, but I might be missing something. For example if failing =
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