Re: Public-Key authentication for websites

I'm not sure if this is the right list (nor how precisely, for that  
matter, I got onto this list :) but how does your idea differ from  
just using client certs?  Yes, that potentially means the format of  
your GPG key might not be directly compatible, but there is pretty  
widespread use of, for instance, government-issued non-repudiation  
keys for e-government stuff.

As far as I know, though I haven't looked in detail, most modern  
browsers allow sites to store client certs, and to request client  
certificates as part of the TLS handshake.

Or am I totally missing your point?

Johnathan


On 14-Feb-08, at 7:00 PM, Christoph Hack wrote:

>
> Hiho everybody,
>
> today Public Keys are very popular and most Internet applications
> support GPG-Keys (e.g. lots of Mail readers and Jabber). Those public
> keys are much more secure and the user doesn't have transmit his
> password and remember it.
>
> But up to now, there aren't any Web Browsers which support a way to
> ask the user to sign something with his personal GPG Key. (please tell
> me if I'm wrong). But I think if somebody could write a RFC or  
> something
> similar for that, there might be a chance of getting this feature into
> some full-featured browsers :)
>
> Use Case:
> A use case for that could be the authentication handling for a web  
> site.
> The websites must provide an (optional) way for the user to attach his
> public keys to his profile and when the user wants to log-in, it's
> enough if he is able to decrypt or sign a specific message.
>
> Benefits:
> - the user must not remember different passwords
> - it's probably much more secure than other password handling methods
> - websites could use this as an alternative authentication method
> - Bruce Force attacks against hashes in big databases (like recently  
> on
>   phpbb, woltlab, smf) aren't possible any more
> - and yes, I know that this idea is similar to OpenID, but it doesn't
>   require any additional services
>
> Problems:
> You can't use static messages for signing or decrypting, because then
> there is a high risk that somebody might collect and use the
> authentication information again. On the other side, completely  
> dynamic
> keys allow the server to get any messages signed by the user, probably
> with content the user don't want to sign. So there must be a well
> defined format (for example a tuple including a general header to
> describe the context, a domain and a secret (session)-key)...
>
> So, I am very interested in your opinion now. Do you think there is a
> way to get a feature like that? Or is this idea just a crap?
>
> Regards,
> Christoph Hack
>
>
> PS: I hope this is the right ML to share this idea, if not please
> redirect to the right one...
>
>
>

---
Johnathan Nightingale
Human Shield
johnath@mozilla.com

Received on Friday, 15 February 2008 15:42:20 UTC