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

Patrick Pelletier <code@funwithsoftware.org> Mon, 23 September 2013 06:43 UTC

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From: Patrick Pelletier <code@funwithsoftware.org>
To: Yoav Nir <ynir@checkpoint.com>
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Date: Sun, 22 Sep 2013 23:43:07 -0700
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Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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On Sep 22, 2013, at 10:21 PM, Yoav Nir wrote:

> Some people are suggesting that clients break the connection if  
> offered a 1024-bit group. It does make sense that they would break  
> the connection if offered, say, a 512-bit group, no?

True, I think it's reasonable to break the connection for 512, but not  
for 1024.  1024 is "not great security, but not utterly laughable,  
either," so the client ought to accept 1024 if the server offers it.

> No, it's different asking a vendor to change something vs asking end  
> users to recompile Apache.

I think the difference is that the mod_ssl issue is just a matter of  
inertia and might eventually be fixed upstream, while the Red Hat ECC  
position is an institutional policy formulated by lawyers, and is  
unlikely to change.

--Patrick