Re: openssl-blacklist & two keys per one pid

[Kees Cook <kees@ubuntu.com>]

On Mon, May 19, 2008 at 01:09:25AM +0200, Jan Tomasek wrote:
> My colleague developed script for converting X509 certificates to SSH  
> key hash. It was strange when we realized that none of issued  
> certificates matched. It is because OpenSSH and OpenSSL blacklist are  
> not compatible. OpenSSH and OpenSSL are using diferent exponent when  
> creating private key.

That's correct -- this is true for OpenVPN as well.

> The rule is simple. When the ~/.rnd file doesn't exist I get one key and  
> in other situation I get another (that listed in Ubuntu  
> openssl-blacklist) key. Because of this problem openssl-blacklist has to  
> be twice big than openssh-blacklist. I developed simple shell scripts to  
> generate list of all key lengths we are interested in. They are attached.

Yes, this was realized during the generation of the openssl-blacklist in
Ubuntu.  We're expecting to have the more complete lists published soon,
for all 3 architectures.

> I also published full list of compromited keys in lengths 1024 and 2048  
> for Intel 32bit and 64bit platforms on my website. There is more keys  
> than in Ubuntu blacklist, but I'm missing others. I'm planning to  
> publish 4096 bit keys list tomorrow. I'm not going to publish complete  
> archives of private keys.

Thanks!  We can verify our lists against yours to make sure we're all on
the same page.  :)

-Kees

-- 
Kees Cook
Ubuntu Security Team