Re: [TLS] draft-sheffer-tls-bcp: DH recommendations

Yaron Sheffer <yaronf.ietf@gmail.com> Sun, 22 September 2013 05:34 UTC

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Date: Sun, 22 Sep 2013 08:34:22 +0300
From: Yaron Sheffer <yaronf.ietf@gmail.com>
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To: Yoav Nir <ynir@checkpoint.com>
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Cc: Patrick Pelletier <code@funwithsoftware.org>, "<tls@ietf.org>" <tls@ietf.org>
Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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It's not "only" Java, it's Windows (Internet Explorer), too. See 
http://blog.ivanristic.com/2013/08/increasing-dhe-strength-on-apache.html, 
last paragraph.

Thanks,
	Yaron

On 09/22/2013 07:00 AM, Yoav Nir wrote:
>
> On Sep 22, 2013, at 2:44 AM, Patrick Pelletier <code@funwithsoftware.org>; wrote:
>
>> On 9/21/13 9:42 AM, Michael D'Errico wrote:
>>
>>> The problem is that there apparently is lots of TLS code which can only
>>> handle
>>> 1024-bit DH parameters and would break if a server sent larger parameters.
>>
>> Doesn't this "lots of TLS code" boil down to just Java?  That's the only implementation I've heard of that supports DHE_RSA but chokes on 2048 DH.  Is there another?
>
> There's also Apache, the most common web server on the web, that doesn't have configuration parameters for EDH key lengths, and tells OpenSSL to use 1024 bits.
>