[TLS] TLS1.3 HkdfLabel - value of label<0..6> ?

M K Saravanan <mksarav@gmail.com> Sun, 31 March 2019 12:39 UTC

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From: M K Saravanan <mksarav@gmail.com>
Date: Sun, 31 Mar 2019 20:38:47 +0800
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Subject: [TLS] TLS1.3 HkdfLabel - value of label<0..6> ?
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Hi,

https://tools.ietf.org/html/rfc8446
============
7.1.  Key Schedule

   The key derivation process makes use of the HKDF-Extract and
   HKDF-Expand functions as defined for HKDF [RFC5869], as well as the
   functions defined below:

       HKDF-Expand-Label(Secret, Label, Context, Length) =
            HKDF-Expand(Secret, HkdfLabel, Length)

       Where HkdfLabel is specified as:

       struct {
           uint16 length = Length;
           opaque label<7..255> = "tls13 " + Label;
           opaque context<0..255> = Context;
       } HkdfLabel;
============

In this struct, what is the value of label<0..6>?

with regards,
Saravanan

[TLS] TLS1.3 HkdfLabel - value of label<0..6> ? M K Saravanan
Re: [TLS] TLS1.3 HkdfLabel - value of label<0..6>… Ilari Liusvaara
Re: [TLS] TLS1.3 HkdfLabel - value of label<0..6>… Blumenthal, Uri - 0553 - MITLL
Re: [TLS] TLS1.3 HkdfLabel - value of label<0..6>… M K Saravanan
Re: [TLS] TLS1.3 HkdfLabel - value of label<0..6>… Hugo Krawczyk