[rddp] RDDP WG Seoul minutes

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RDDP WG meeting minutes
IETF-59, Seoul
March 3, 15:30-17:30
-----------------------

Many thanks to Tom Talpey for taking these minutes.

The agenda was: 

- Agenda Bashing and Administrivia (5 min) 
        - Blue Sheets 
        - NOTE WELL 

- Status of drafts (5 min) 

- Applicability Statement (5 min) 
        (draft-ietf-rddp-applicability-01.txt) 

        Mostly a status update. 

- DDP and RDMAP drafts (10 min) 
        (draft-ietf-rddp-ddp-02.txt, draft-ietf-rddp-rdmap-01.txt) 

        Mostly a status update. 

- SCTP Mapping (5 min) 
        (draft-ietf-rddp-sctp-00.txt) 

        Despite the -00 version number, this is the fourth version 
        of this draft, and it is relatively mature. 

- TCP mapping (30 min) 
        (draft-ietf-rddp-mpa-00.txt, 
        draft-culley-mpa-issueresponses-00.txt) 

        The mpa-issueresponses draft is a separate draft from the 
        MPA authors describing issues raised in MPA and proposed approaches.


- Security (60 min) 
        (draft-ietf-rddp-security-01.txt) 

        Time allocated reflects the importance of progress on this draft. 

----- 

Agenda bashed - no changes 
Blue sheets, Note Wells, etc. 

- Status of drafts (David Black, WG chair): 

  Problem Statement, architecture documents are in IESG discussion. 
  Feedback from IESG is in-progress and docs will be revised. 

  Main protocols (DDP, RDMAP): No open issues. Changes are expected 
  in the Security Considerations, however. 

  Applicability Statement: Probably in good shape, but please take a 
  new look in light of current progress. 

  SCTP mapping: One open issue - need for active/active startup?
  The plan is to discuss this in context of MPA, and provide the
  same functionality via TCP and SCTP for consistency. This document
  will be a Proposed Standard RFC. 

  MPA (TCP mapping): Open issues revolve completely around startup, 
  not operation. To be discussed today. This document will be an 
  Informational RFC. 

  Security mapping: WG chair has consulted with Area Director - this
  will be a Proposed Standard RFC.  Because it covers endpoint behavior,
  it's appropriate for a standards draft. Also, the IPsec mapping is
  applicable to multiple transport protocols, so its text can and
  should be shared in a single RFC. 

- TCP Mapping (MPA) discussion. (David Black presenting for Paul Culley) 
  (see presentation C-MPA update040225.ppt) 

  (1) Fast FPDU return (responder need not wait for first pdu). 
  Tentative proposal: leave as-is (responder must wait). 
  No dissension in room.  This is not needed for client/server,
  as the server expects to wait for the client.  Need to take
  proposal to the list. 

  (2) Active/Active startup. Tentative proposal: leave as-is (no 
  support for active/active). No dissension in room.  Note, no 
  known applications require it.  Need to take proposal to the list.

  (3) Rejected Connection bit. Dissension expressed, this leads to 
  interoperability issues because it forces a ULP to interpret private 
  data to figure out that the connection setup failed, and requires
  MPA to handle TCP close specially (more detail in mail to list).
  Further discussion: 

  Q: If MPA does not do "teardown", why is the bit needed to 
   free resources at MPA layer? 
  A: Practically speaking, implementations will allocate and free 
   resources in MPA (e.g. connection model in kernel), this enables 
   layering and better control. 
  A: The bit will prevent some timed-wait resource consumption issues,
   if used properly (this is about cooperating systems, not malicious
   resource consumption attacks).

  Rough consensus in room to include the bit. Take to list. 

  See presentation for other nits in-progress (will be taken care
  of in next revision of draft).

  NOTE: separate list consensus call emails will be sent to start and
      focus discussion on issues (1) thru (3).  Please wait for them!

- Security discussion (Ellen Deleganes): 
  (see presentation D-RDDP Security presentation 040302.ppt) 

  New author, Sara Bitan, joins Jim Pinkerton and Ellen. 

  Main change, the document has been reorganized. This is in 
  response to comments, and all feedback is welcomed. 

  The term "Partial Trust" was changed - needed a crisper meaning. 
  Now called "Partial Mutual Trust". Defines a cooperative set of 
  streams.  Discussion: what does this mean? Concept seems better
  but the name is still problematic. Basically, it seems to define
  a set of assumptions that can allow simplification (efficiency) for 
  cooperative streams. Trusting that they will not attack one 
  another - but still protecting the server. 

  "Queue"-level granularity is new (and useful) text. But, 
  the word "queue" may have to go, because the doc will be 
  normative. We can't assume a queue in normative text. Or, add 
  text such as "the use of the word 'queue' does not imply that
  this implementation actually contains a queue"... 

  New section - "security services for RDDP" - has a list of attacks 
  listed - good progress. 

  One issue in Security section - now mentions SSL. This will require 
  more text because of ordering issues. SSL is a bad match because 
  of its stream orientation.

  Section 9 - Should we require IPsec, and therefore implement 
  this section, or make it optional? Suggestion that it be made 
  "mandatory-to-implement, optional-to-use." It was observed that 
  IPS had a similar section because it needed it. Also, now that 
  there is the IKEv2 specification to refer to, the problem is no longer 
  so difficult to document.  Look at IKEv2 and new "Cryptographic
  Algorithms for IKEv2" draft.  If these are used this section in
  the RDDP security draft may not be necessary, as an IKEv2
  reference will be adequate. 

  (4) Core question: Should we say that IPsec is mandatory for RDDP? 
  Secondary question: What parts do we actually require? (IKEv2?) 
  Take to list! Also, take to NFSv4 WG the next day. (NFS has no 
  such requirement currently, and has its own RPCSEC_GSS security 
  support). 

  The mandatory security item generated significant discussion but was 
  highly inconclusive. It was observed that mandatory-to-implement 
  would be a significant enhancement to the review approval process. 

  Appendix A - remove or keep? No conclusion, but possibly best to remove? 
  May want to keep some of it - taxonomy, etc., which contains useful 
  raw material for a revised Summary section. Summary section: perhaps 
  have a summarized list of MUST and SHOULD requirements, etc. 

  Partial placement text additions are an open issue. (e.g. place code, 
  via RDMA into a buffer, then attack the server in some other fashion to 
  run that code) Draft should note these as a risk and state that buffer
  overflow protection is actually stronger with RDMA, and why (byte-level
  protection with bounds).

  (5) Need to address "protection for shared RQ" problem. The security draft

  makes a "valiant" attempt to make it a ULP issue - but can't. Exhaustion 
  of receive buffers is a key attack. Is this the job of each and every ULP,

  or RDDP's? Probably the latter.  OTOH, there is general discomfort with
  specifying this in a fashion that would require checking it in the fast
  receive path (e.g., in hardware in a hardware-optimized implementation). 

  Scenario - server mis-implements resource management, bug in one 
  handler drags down others. E.g., a multiprotocol server with busted 
  filesystem component kills HTTP, etc. "Unsafe by design", i.e. RDDP 
  should not impose non-uniform controls. 

  The goal is to specify a functionality that is guaranteed to exist, 
  though possibly overridable given sufficient trust.  Absence of any
  required control here doesn't line up with the Partial Mutual Trust
  concept discussed earlier.
 
  Proposed approach: Require a default implementation of this protection,
  as part of the Privileged Resource Manager. Privileged protocols can
  override it, but the base function is always provided.

  Does a similar situation exist for CQs? 
  (Response: yes, with suppressed completions, underprovision is desirable!)

  NOTE: separate list consensus call emails will be sent to start and
      focus discussion on issues (4) and (5).  Please wait for them!

---- 

At the end of the session, the Area Director commented he was glad to 
see significant work being done in meeting, and was pleased with the 
progress. 

<adjourns 17:05> 


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