I was under the impression that this list was to discuss things pre-draft -- e.g. general concepts first, details later in a specific work-group. I'm sorry if you find the piece meal approach difficult.
My proposal in a nutshell: 1. Use TLS strong authentication between client and server on all connections over the internet to obviate MITM attacks. 2. Make users' public keys public information to obviate current TLS limitations on obtaining them. If everyone agrees with this, we can certainly move onto a draft to work out details, and yes, I'd need assistance from that point onward. Karl -----Original Message----- From: Stephen Farrell [mailto:[email protected]] Sent: Thursday, September 12, 2013 09:47 To: Karl Malbrain Cc: Jon Callas; Theodore Ts'o; [email protected]; Phillip Hallam-Baker Subject: Re: [perpass] proposed enhancement to TLS strong authentication protocol Hi, We seem to be designing this protocol one mail at a time. Could I ask that we stop doing that and that Karl and whoever else is minded submit an internet-draft specifying the protocol so that it can be more easily reviewed. Thanks, Stephen. PS: Karl, if you need help with the mechanics just ask me offlist. On 09/12/2013 05:24 PM, Karl Malbrain wrote: > The assumed attack profile is a MITM insertion into a connection stream > between server and client whereby the attacker gains complete unencrypted > access to all traffic over the connection, not just meta data. > > TLS already has a built-in concept of "strong authentication" between server > and client to defeat this attack. It requires that the TLS server pre-obtain > by some secondary channel the public key of the user. This proposal > eliminates that requirement by making the user's public keys public knowledge. > > Karl > > From: Jon Callas [mailto:[email protected]] > Sent: Thursday, September 12, 2013 06:21 > To: Karl Malbrain > Cc: Jon Callas; Phillip Hallam-Baker; Theodore Ts'o; [email protected] > Subject: Re: [perpass] proposed enhancement to TLS strong > authentication protocol > > > On Sep 11, 2013, at 11:56 AM, Karl Malbrain > <[email protected]<mailto:[email protected]>> wrote: > > > The goal of the proposal is to enable the use of strong authentication for > all TLS connections over the internet. The certificates as > things-in-themselves don't really matter, they are actually just a vehicle to > post the public key of the user/server in a reliable public place. The > security occurs when the challenges to prove private key ownership are > cross-issued by each party. MITM would not have the private keys to answer > either challenge. > > Note that this still doesn't solve the problem of MITM obtaining the server's > private key. I'm still working on that one. > > I might be misunderstanding, but it seems to me that your global directory > would allow a passive listener to fingerprint the client by sniffing in a > variety of places -- near the client, near the server, or near the directory. > > If you assume an attacker interested in collecting metadata about the > clients, this would be suboptimal. > > I may be missing something, but this sounds like it is just a global, central > certificate authority, albeit one that is not actually issuing the > certificates, but still assigning them GUIDs, which are by definition > globally unique. > > Am I indeed missing something? > > Jon > > > > > _______________________________________________ > perpass mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/perpass > _______________________________________________ perpass mailing list [email protected] https://www.ietf.org/mailman/listinfo/perpass
