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Re: [TLS] A small detail in HMAC key generation for Finished message

Eric Rescorla <ekr@rtfm.com> Tue, 05 January 2016 00:20 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 04 Jan 2016 16:19:36 -0800
Message-ID: <CABcZeBNQgH6SJVuRggQyDDZ6RNfb=T5Gt3Zh=aEZ-FF=_x1vrQ@mail.gmail.com>
To: Martin Thomson <martin.thomson@gmail.com>
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] A small detail in HMAC key generation for Finished message
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On Mon, Jan 4, 2016 at 4:11 PM, Martin Thomson <martin.thomson@gmail.com>
wrote:

> On 5 January 2016 at 05:03, Eric Rescorla <ekr@rtfm.com> wrote:
> > Ask and ye shall receive:
> http://tlswg.github.io/tls13-spec/#digital-signing
> >
> > "Following that padding is a context string used to disambiguate
> signatures
> > for different purposes.
> > The context string will be specified whenever a digitally-signed element
> is
> > used. A single 0 byte is
> > appended to the context to act as a separator."
>
>
> You call this NUL in the following paragraph, without context.  This
> might need to be tied together better.
>

Fixed.

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