Re: [TLS] Last Call: draft-ietf-tls-extractor (Keying Material Exporters for Transport Layer Security (TLS)) to Proposed Standard

Erick O <> Fri, 18 September 2009 14:53 UTC

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Date: Fri, 18 Sep 2009 07:47:22 -0700 (PDT)
From: Erick O <>
To: Douglas Stebila <>, IETF Discussion <>
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Subject: Re: [TLS] Last Call: draft-ietf-tls-extractor (Keying Material Exporters for Transport Layer Security (TLS)) to Proposed Standard
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From: Douglas Stebila <>;
To: IETF Discussion <>;
Sent: Tuesday, July 21, 2009 1:32:21 AM
Subject: Re: [TLS] Last Call: draft-ietf-tls-extractor (Keying Material Exporters for Transport Layer Security (TLS)) to Proposed Standard

I have implemented draft-ietf-tls-extractor-06 in the TLS v1.0 implementation in OpenSSL.  I found the draft easy to implement with no ambiguities or concerns.  I believe that the functionality provided by the draft will be extremely valuable for building application-level security protocols and encourage its standardization.

It is my interpretation of the draft that it can be implemented in any version of TLS, not just TLS v1.2.  Obviously the derived key may be different if the underlying TLS PRF is defined differently (as it is for TLS v1.2), but the draft is still well-defined for previous versions of TLS.

For those interested in the OpenSSL implementation, I have posted a page on my website with the patch.
In addition to a patch for OpenSSL, I have also done patches to Apache and PHP to expose a PHP function that allows a PHP application to derive keying material from the underlying TLS connection according to the draft specification.


On 2009-Jul-21, at 2:48 AM, The IESG wrote:

> The IESG has received a request from the Transport Layer Security WG
> (tls) to consider the following document:
> - 'Keying Material Exporters for Transport Layer Security (TLS) '
>  <draft-ietf-tls-extractor-06.txt> as a Proposed Standard
> The IESG plans to make a decision in the next few weeks, and solicits
> final comments on this action.  Please send substantive comments to the
> mailing lists by 2009-08-10. Exceptionally,
> comments may be sent to instead. In either case, please
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