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Re: Cosign Re-Authentication Specification

On 25 Mar 2005, at 15:59, Cory Snavely wrote:
* Suggestion. On the re-auth page, it occurs to me that if someone
  *innocently* arrives there, they are unlikely to suffer through n
  attempts at impersonation without knowing that afterward they get
  to authenticate as themselves. The way it is currently kind of
  assumes they are up to no good.

  I think there should be a "this isn't me--log on as a different
  person" button. Not quite sure how to word that, but I think it's
  needed to help the innocent victim.

Good idea. Let's add a button/text. If the user selects this path, they will logout the previous user, and be redirected back to the URL. Since the URL required (unsatisfied) reauthN, there should be no cached cookies, the "CHECK" will fail, a new service cookie will be set, and a login will be triggered.

* I agree with the others that the *service* sometimes needs to have
  weblogin force reauthen. I definitely can think of instances where
  the service might want to decide to reauth--for example, for a
  particularly sensitive operation, as you see on e.g. or
  travelocity before you complete a transaction.

To do that securely, though, the application must somehow communicate
that need to the local cosign module or weblogin. I think this is
trickier than it sounds to do in such a way that the user can't
easily defeat. The two secure approaches I can think of require

So, I would propose that service-side forcing of authen--IOW, forcing
authen *after* a service cookie exists--be considered a case of the
"authen timeout" feature that has been discussed before. I would
conceive this as Apache directives that specify pairs of regexps and
time thresholds that the local cosign module enforces by ignoring the
service cookie if the age of authen falls outside the allowable
parameters. Set it to 15 seconds for a regexp that matches your VISA
card entry page URL; set it to 10 minutes for a regexp that matches
the whole financial module of your application.

  So, a distinctly different feature, and not combined with this
  proposed reauth change for whole services that always require
  reauthen for entry.

As of 1.7.x, cosign service cookies have timeouts. Currently, they are server-wide, but it could be moved to a directory/location.


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