Re: [Unbearable] one proposal for a charter - please dicsuss

[Phillip Hallam-Baker <[e-mail]>]

On Mon, Dec 8, 2014 at 6:19 PM, Stephen Farrell <[e-mail]>
wrote:

>
> Hi all,
>
> There's about 70+ people on the list now so let's kick off.
>
> Andrei sent Kathleen and I the charter proposal below a while
> ago. For myself I don't think its quite right yet but I'd
> rather hear what you all think. So please discuss...
>
> Cheers,
> S.
>
>
> Token Binding (TB)
>
> Charter for Working Group
>
> Web services generate various security tokens (e.g.  HTTP cookies, OAuth
> tokens, etc.) for web applications to access protected resources.
> Currently these are bearer tokens, i.e. any party in possession of such
> token gains access to the protected resource. Attackers export bearer
> tokens from client machines or from compromised network connections,
> present these bearer tokens to Web services, and impersonate
> authenticated users. The idea of Token Binding is to prevent such
> attacks by cryptographically binding security tokens to the TLS layer.
>
> The tasks of this working group are as follows:
> 1.            Specify the Token Binding protocol v1.0.
> 2.            Specify the use of the Token Binding protocol in
> combination with HTTPS.
>
> It is a goal of this working group to prevent security token export and
> replay attacks, but other issues associated with the use of security
> tokens are out of scope. It is a goal of this working group to design
> the Token Binding protocol such that it would be also useable with
> application protocols other than HTTPS, however specifying such uses is
> not a primary goal.
>

Umm, I am still rather fuzzy about what is proposed here Stephen.

In particular I don't think we are getting away from bearer tokens, we are
just hiding them different.

This is a draft I have been working on for a while. It allows a token to be
bound to a HTTP/TLS channel.

http://tools.ietf.org/html/draft-hallambaker-httpsession-03


It might help if we had a definition of bearer token. I don't think that
formulation is helping. The problem is not that we have bearer tokens, it
is that our proofs of possession force them to be disclosed in plaintext to
the party checking them.

Is an RSA private key a bearer token?
How about a kerberos ticket?


Presenting this as a problem with the token puts us off track. The problem
is with the way we use them.