- From: <jg@zorch.w3.org>
- Date: Thu, 19 Sep 96 11:27:55 -0400
- To: Jim Whitehead <ejw@ics.uci.edu>, w3c-dist-auth@w3.org
- Cc: Alan Freier <freier@netscape.com>
Alan is certainly right about what is going on around MD5 in the industry and in research. While Ron Rivest's (the R of RSA) reply to me earlier this week was for our purposes in HTTP Digest authentication plain MD5 was probably just fine, it is also clear that some people will not be comfortable with its use, as it has recently shown certain classes of vulnerabilities. Each time some vulnerability comes up, we don't want to have to always deal with understanding its implications to HTTP work, but should leverage other people's crypto work as much as possible. In the area of what HTTP should do semantically, we really don't want/need to take on all cryptographic problems too. We need to get the HTTP documents to correctly interact with all the IP security work going on in the IETF, so that this problem doesn't come back to haunt HTTP work forever. IPSEC is specifing a hash function for authentication purposes; the way out of the morass is to organize things to reference (as soon as possible; it may not currently trivial to do this instant on process grounds for things like Digest, as the IPSEC documents themselves are being revised and may not be far enough along for us to reference them to meet IETF process standards for proposed standard that Digest is at) the IPSEC work on authentication functions, rather than get into it ourselves. My understanding from a hallway conversation yesterday with Matt Thomas of Digital (involved in the IPV6 work) is that IPSEC is going with MD5-HMAC right now (whatever exactly that is; it is a variation on the original MD5 algorithm), and I asked Matt to get me information on who is shepherding these IPSEC documents through the IETF process so I could understand what was happening there to deal with IETF process issues (we have much the same problem right now with Digest authentication, where we specify which algorithm and are not in the midst of the people who are expert in this area), to address Phil Karlton of Netscape's concerns about Digest. I'll be trying to sort this out some over the next couple days, if I can. - Jim
Received on Thursday, 19 September 1996 11:28:20 UTC