On 22.12.2017 01:12, Colony.three wrote:
> 
>> You can't do that. The DH groups for IKE are standardized.
>> "bot search will compromise VPNs in seconds"? What do you mean with 
>> "compromise" exactly?
> 
> I said what I mean or course, in the next sentence:  "/Most VPNs today are in 
> fact decrypted real-time and stored in the NSA's giant facility in Utah, 
> according to the Snowden docs./" (Actually they first go through the 
> decryption group in Ft Meade, MD)
> 
>> Discoverying the existence of a service does not compromise it in any way.
>> Unless you do stupid things like using PSKs and making them public or using 
>> a weak DH group, you can't decrypt them. I read the Snowden docs. And the 
>> ones from the Spiegel.
> 
> IPsec traffic can be easily identified of course, with packet inspection.  
> And with the precomputed (canned) DH group applied to it, it's a shortcut to 
> the cleartext for a well-funded opponent (which implicitly has access to the 
> fiber trunks).  It is not my goal to get in to an argument about this, Noel.  
> Please see Schnier's papers on this from 2014, and "I Hunt SysAdmins", et al. 
> (I won't stoop to condescending you)
>

Neither is mine.
Which of Bruce Schneier's papers from 2014?

>> IKE and TLS do the DH exchange differently.
>> In TLS, the server sends its DH parameters to the client. In IKE, that does 
>> not happen. That is the reason you can use your own DH parameters with TLS, 
>> but can't with IKE.
> 
> I guess you will end this exchange now because this is hard for me to 
> believe.  How has such a vuln been overlooked for so long by so many 
> highly-competent people?  A common DH group for -everyone-?!  What do they 
> think the point of it is?
> 
> 

There are many DH groups[1]. Pick one that is strong enough for your taste. 

I very much doubt the NSA can break anything above 1536 bits. Even 1024 bit is 
hard[2], because the lookup table required for it is humonguous.

[1] 
https://wiki.strongswan.org/projects/strongswan/wiki/IKEv2CipherSuites#Diffie-Hellman-Groups
[2] https://weakdh.org/

Attachment: signature.asc
Description: OpenPGP digital signature

Reply via email to