Re: [Monotone-devel] Re: key trust

[Brian Campbell]

On Oct 12, 2005, at 4:36 AM, Richard Levitte - VMS Whacker wrote:

> I think you're operating under some false assumptions.  Just because a
> certificate was revoked yesterday, it doesn't mean that a signature
> made a week ago suddenly becomes invalid.  All that's needed is to
> attach a datetime to the thing being signed before signing it, and
> compare that to the revokation datetime to know if the signature is to
> be regarded as valid or not.

How do you know if the datetime is honest? If I have my certificate  
revoked, I could create a revision with a date/time earlier than the  
revocation and push it to a server. If you wanted to actually make  
sure things happened ate the right date and time, you'd have to have  
a centralized, trusted, timestamping server. Pretty much the only  
thing you can do in a system like monotone is list a set of  
revisions, and say all of those revisions are still trusted, while  
any more from someone with that certificate are not.

Actually, I'm wondering if it wouldn't be simpler to just re-sign all  
certificates for existing revisions that are signed with a key that  
is about to be revoked.