Re: [TLS] TLS 1.3 Key Schedule

Eric Rescorla <ekr@rtfm.com> Fri, 04 September 2015 15:36 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 04 Sep 2015 08:33:34 -0700
Message-ID: <CABcZeBPnUesZE4Tr8ek4aFXmio4epCjivUTHgU++GQ8Uc5b16g@mail.gmail.com>
To: Russ Housley <housley@vigilsec.com>
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Cc: IETF TLS <tls@ietf.org>
Subject: Re: [TLS] TLS 1.3 Key Schedule
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See:
http://www.ietf.org/mail-archive/web/tls/current/msg17184.html

On Fri, Sep 4, 2015 at 8:27 AM, Russ Housley <housley@vigilsec.com> wrote:

> In Section 7.1, the document says:
>
>      4. finished_secret = HKDF-Expand-Label(xSS,
>                                             "finished secret",
>                                             handshake_hash, L)
>
>      5. resumption_secret = HKDF-Expand-Label(master_secret,
>                                               "resumption master secret"
>                                               session_hash, L)
>
> Why don't we use the master_secret in both the finished_secret and the
> resumption_secret formula?
>
> Russ
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