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Re: [TLS] Extended random is NSA backdoor

Nico Williams <nico@cryptonector.com> Tue, 01 April 2014 00:31 UTC

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Date: Mon, 31 Mar 2014 19:31:44 -0500
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From: Nico Williams <nico@cryptonector.com>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [TLS] Extended random is NSA backdoor
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If this is in reference to Dual_EC, well, TLS has always had enough
bytes of nonce to exploit the conjectured Dual_EC backdoor (assuming
one did not feel forced to send the 32 bits of Unix time, which,
indeed, some libraries _don't_).

The Reuters article doesn't provide a real source, just a source of
speculation, so it's hard to say.  It seems like a plausible attack
because of the 32-bit Unix time, and because the normal 32-byte nonces
might not be a contiguous 32-byte output of Dual_EC.  And because
there was no pressing need for extra entropy.

Note that even if this really was the intention of RSA/NSA at the
time, EKR might not have known it.

Nico
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