Subject: [abfab] abfab@IETF80 minutes

From: Klaas Wierenga <[email-masked]>
Date: Mon, 04 Apr 2011 16:15:38 +0200

Hi all,

Please find below the abfab session minutes, with thanks to the note
takers and jabber scribes!

Klaas & Leif

=====
Abfab WG Minutes

IETF 80
Prague, Czech Republic
Abfab 1: 15.10-16.10 Monday March 28, 2011
Abfab 2: 09.00-11.30 Thursday March 31, 2011

Chairs:
Klaas Wierenga <[email-masked]>
Leif Johansson <[email-masked]>

- ----------------------------------------
abfab 1 (monday)
- ----------------------------------------
Note well
Note taker established (Stefan Winter)
Jabber scribe established (Jeffrey Hutzelman)
agenda approved

ABFAB Architecture draft (Eliot Lear)
- -------------------------------------------------
draft-lear-abfab-arch-02

Josh Howlett (Josh) at mic for privacy considerations:
   most people think of privacy is on "ethical level"
   Josh thinks along "keep RP/IdP out of prison" - privacy regulations exist
   User consent one vehicle for privacy - RPs need some attributes; but
not others
   * user-centric paradigm - let the user disclose everything he wants
   * non-user-centric: third party releases, e.g. IdP
   technology needs to provide enough privacy support to satisfy regulations

Sean Turner at mic:
   IESG review comments on security considerations, need to be spelt out
in detail

Sam Hartman (Sam):
   on coop with kitten: channel bindings in MS are implemented "kinda
cool" - but is
      not possible with GSS. kitten and abfab work is required to to get
similar functionality in
      (issue is: how to handle not being sure if the other end supports
channel binding upfront)

Leif: do we need to recharter if normative text sneaks into arch
document? Sam suggests operational/implementation best-practice
document. Individual submissions solicited.

Eliot: text is small though; and informative text can have normative lingo.

Hummed: in favor of approach (unanimous, overall low participation, to
be confirmed on the list). Leif again solicited individual drafts; for
later adoption by WG.

ABFAB Use-Cases (Rhys Smith)
- --------------------------------------------
draft-abfab-usecases-00

Aaron Falk (BBN): Geni project uses federated identity for access to
testbeds. Use case: access to networking resources. Aaron will read the
draft to see how it fits in.

Jim Schaad: plug for plasma BOF. plasma should be building on ABFAB. Use
case: distribution of stuff over mail protocol; but need federated
access to these.

Show of hands: 2 readers of draft; needs more input from community. Leif
encourages everybody to read!

Presentation of Project Moonshot (Sam Hartman)
- -----------------------------------------------------------------
Abfab VM was tried out: proof of concept showed to work indeed

Leif: doing UI work is in charter, work waiting to be done - will
discuss in abfab2

Sam: SAML is being used differently than usual - leads to authorization
question: need to request attributes on behalf of someone else.

Sam: not ready for production use at all! Play with it only.

- ----------------------------------------
abfab 2 (thursday)
- ----------------------------------------
Note well
Note taker established (Linus Nordberg)
Jabber scribe established (Melinda Shore)
agenda approved

GSS-EAP (Sam Hartman)
- --------------------------------------------
- - slide "name format":
Jeffrey Hutzelman (jhutz): there's a bug in the name format
    - on anonymous: wellknown/ANONYMOUS is used, but sending empty ("")
      in RADIUS

jhutz: make GSS look less like Kerberos

Sam: minimizing implementation costs but this
        anonymous case probably stretches it

Jhutz: worth examining to use empty but don't forget the
        anonymous flag

Leif: charter doesn't mention Kerberos

Lucy Lynch: abfab is not only about Moonshot. please
        avoid confusion.

Jhutz: 1. the accessor might not know [acceptor?] due to
        multiple hops

Leif: ask kitten to revisit anonymous for gss? sam: not
        yet.

Jhutz: they might take a long time to come up with an
        answer better than what sam is saying here and what kerberos
        already has.

Leif: moonshot does things that doesn't correspond to anything
        in the spec?

Sam Hartman on the subject of name formats:
We will do the following:
          1. fix the abnf to note problems with "anonymous" using a
slash when you don't have a host component
          2. specify anon behavior. empty name is the best.
          3. document realm anonymous name and the implications of it
          4. dicusss i8n

  - slide "eap method req"
    - should we say "always eap channel binding" or only when mutual
      authn is being done? no reply. sam: please have opinion on list.
      sam: should i explain it here or? for reasons of time constraints,
      no.

  - "proposed solution"
    - strong opinion on names? no response.

  - "requirement for MIC"
    - [RFC 3961 doesn't have an incremental hash -- implementer will
      have to store full state before being able to send it.  client
      need memory to hold the complete conversation.  large cookies
      might be another the effect.]

Jim Schaad: what if i want to carry on a conversation
      _before_ i've been at an idp?  sam: PLASMA case, the blob
      shouldn't be a part of the request, perhaps only a hash of the
      blob.

Jim: layering problem.

Jhutz: application like imap, before sasl gss server says mech
      support here, then some roundtrips, if imap + starttls and then
      you want to autn again but you'd have to renegotiate.

Leif: PLASMA is an important use case but we need to finish this.
      please repeat the three options.

Sam on the options for MIC:
      - opt 1. integrity protect each token, f.ex. the flags token
      - opt 2. signon a hash function, EAP+<3961-enctype>+<hashfunc>
      - opt 3. use large tokens
      - opt 4. don't integrity protect large thingies (bad option!)

Sam: the maximum complexity for opt 1 might be substantial

Luke: opt 5. would be revise 3961 and couldn't we put this in GSS
      channel binding?

Sam: need help from someone who understands RADIUS VSA's
      and 2. how do i register an entry with IANA

    - Hannes Tschofenig will help Sam with RADIUS
      VSA's and how to register with IANA

RADIUS atttrib for SAML (Josh Howlett)
- --------------------------------------------
  - PLASMA is going with either ws-trust or abfab

Josh: jim, do do use SAML for your "PDP's"?

Jim: this isn't relevant for conversation between client and service

Leif: the IdP can combine them

Scott Cantor: more than one assertion in a response

Luke Howard: standard RADIUS AVP?

Josh: yes.

* Diameter attributes for SAML (Mark Jones)
- --------------------------------------------
  - extending diameter EAP with new AVPs
  - DER: SAML-AuthnRequest AVP
  - DEV: SAML-AuthnRespnse AVP, SAML-Assertion AVP

Josh: difference to radius is you define attributes for specific
    SAML attribs while we have a generic attrib.  reason?

Hannes: easier
    to read, no real semantic difference.

Josh: makes sense. we would
    put it in a AAA binding document, glad for guidance from SAML
    ppl. scott: re SAML binding, we said only request/response because
    the binding wasn't supposed to be a protocol.

Josh: if "we" took
    the same position, we're running out of RADIUS attr space (not
    considering extended attrib proposal).

Sam: hop-by-hop trpt layer security? hannes: TLS and IP-sec.

Scott: an analogy: in http we have explicit routing thanks to urls.

Mark: a proxy should be able to pass along without
    understanding the payload]

Josh: since SAML2 was std 2005 there has been only one new protocol
    defined

Scott: new protocols are not a big deal]

Leif (as individual): you will need attribute query

Sam: think we should use a single AVP unless there are needs for more

Mark: if we return EAP success... sam: in radius we don't have
    cirticial restrictions on success and if we need it, let's do it
    together for RADIUS and diameter.

Leif calls for hums: 1. more or less in the right
    direction? 2. adopt as a wg docu?

Sam: what if we want to say 1 attrib rather than 2, how do i hum on
    number 1?

Leif: adoption means that change ctrl goes to the wg.

Melinda Shore: is this a showstopper for anyone?  no
    replies.

Leif: do you want to decide "this" (one or several AVPs for
diameter) before huming on adoption?
    result: no.

Leif: humming on adoption. result: yes, wg should adopt.

Action: confirm adoption of draft-jones-diameter-abfab as WG
    document as draft-ietf-abfab-diameter with Mark Jones and Hannes
    Tschofenig as document editors on list.

KNP - Key Negotiaion Protocol (Josh Howlett)
- --------------------------------------------
Eliot Lear: flat files laying around?

Josh: yes, and that's
    an administrative problem.

Dave Crocker: how can TLS be not hop-by-hop?  conclusion:
    _trust_ is no longer path-based [?]]

Sam: the routing has similar properties as bgp, but unlike dns each
    hop may have policy and do filtering

Sam: you shouldn't have to run your own introducer if you're too
    small

Jim: is this really abfab? how do the trusted router fit in the
    charter?  [josh: you _could_ have introducers w/o trust routers but
    it doesn't buy you much.]

Leif: this is an invited presentation and not a question of
    adoption.  this is partially a problem statement document and i
    suggest splitting the document in two parts

Mark: s/radius/radius or diameter/g.

Josh: ack.

Mark: introducer == broker?

Josh: yes.

Eliot: useful and interesting presentation, we need ways to deal
    with larger and higher numbers of federations.

NFSv4 (Andy Adamson)
- --------------------------------------------

- - Won't happen since Andy isn't in the room and also we're running out
  of time.

Milestones update
- --------------------------------------------
Leif:
- - emsk will possibly been removed since not used
- - eap applicabililty is getting done by Joe Salowey and Stefan Winter
- - lacking UI usability doc still. question: anyone done anything re this?

Rhys: Janet has some work on UI going on within Moonshot and they will
write an IETF document and Rhys will coedit it.

Leif stares at Bob.

Bob Morgan: i can be
    persuaded to work with Rhys on this because of kantara ULX involvement.

Leif:  Will the documents slip? silence means no.  result: silence.

Rhys: august might be tough.

Josh: no, that's fine. [:-)]

* OID registry (Rhys Smith)
- --------------------------------------------
- - got an oid from iana: 1.3.6.1.5.5.15

Jhutz: why reimplement?

Sam: backwards incompat changes. making
    gss-eap in the next version.

- - Rhys asks implementers to let him know
    when OID's under abfab arc are used.

Closing
- -------

The chairs close the meeting