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Re: [TLS] Questions about some expired drafts

Stephen Checkoway <s@pahtak.org> Fri, 30 January 2015 06:06 UTC

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From: Stephen Checkoway <s@pahtak.org>
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Date: Fri, 30 Jan 2015 01:06:16 -0500
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To: Yuhong Bao <yuhongbao_386@hotmail.com>
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Subject: Re: [TLS] Questions about some expired drafts
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On Jan 27, 2015, at 8:22 PM, Yuhong Bao <yuhongbao_386@hotmail.com> wrote:

> Yea, I believe the draft-rescorla-tls-extended-random is quite famous as a backdoor, 
> along with Dual_EC_DRBG.

Well, it makes attacks easier by exposing more consecutive raw Dual EC output bits. For P-384 and P-521, it makes the attack doable at all (at least in theory, I didn't actually validate that against an implementation that supported extended random like RSA's BSAFE libraries).

-- 
Stephen Checkoway

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