Date: Sun, 04 Jan 2009 09:22:06 +0200 From: Hank Nussbacher <hank@efes.iucc.ac.il>
At 06:44 PM 03-01-09 +0100, Mikael Abrahamsson wrote:
On Sat, 3 Jan 2009, Hank Nussbacher wrote:
You mean like for BGP neighbors? Wanna suggest an alternative? :-)
Well, most likely MD5 is better than the alterantive today which is to run no authentication/encryption at all.
But we should push whoever is developing these standards to go for SHA-1 or equivalent instead of MD5 in the longer term.
Who is working on this? I don't find anything here: http://www.ietf.org/html.charters/idr-charter.html
All I can find is: http://www.ietf.org/rfc/rfc2385.txt http://www.ietf.org/rfc/rfc3562.txt http://www.ietf.org/rfc/rfc4278.txt
Nothing on replacing MD5 for BGP.
I don't see why this is an issue (today). As far as I understand it, the vulnerability in MD5 is that, with time and cycles, it is possible to create a collision where two files have the same MD5 hash, so the counterfeit cert would check as valid. For the MD5 signature on a TCP packet, this is not relevant. Am I missing something? (I will admit to not being a cryptography person, so I may totally misunderstand.) I don't object to moving to a stronger hash, but, considering the expense and time involved, I'd suggest waiting for the new hash algorithm that the NIST challenge will hopefully provide. In other words, stick to MD5 in places where it is not believed to be vulnerable and where converting to SHA-1 or SHA-256 would be expensive. Where it IS believed vulnerable, the cost/benefit ratio would have to determine when the conversion is justified. For X.509 certs, I believe the answer is clearly that it is justified and has been for at least 2 years. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751