Securing Block Storage Protocols over IP: RFC 3723 Requirements Update for IPsec v3
draft-ietf-storm-ipsec-ips-update-04

[Ballot comment]
I want to reiterate and amplify Joel's comment: I think it would be better in the end to re-publish 3723 with these changes and obsolete it rather than doing this as an update. I hate for our tools to drive these sorts of decisions, but if you obsolete 3723 with a new document, the next time someone tries to refer to 3723, the nits tool will say, "Hey, that's obsoleted; do you want to refer to the newer one?" That won't happen if it's just an update. You still want to update all of the docs that normatively refers to the IPSec stuff in 3723, but obsoleting 3723 would be better. Please consider it.

[Ballot discuss]
BTW - this pretty closely mimics the "new" recommendations found in:
http://datatracker.ietf.org/doc/draft-ietf-ipsecme-esp-ah-reqts/ so no worries there.

s2: The use of ESNs is discussed for IPsec v3 but this feature is also supported in IPsec v2, see [RFC4304], should the same requirement be levied against implementations that use IPsec v2?

s5: I agree with the Tom (the secdir reviewer) about the GCM nonce-reuse issue.  There's motivation provided for changing and it seems like while touting how much better GCM is ought to also be balanced out with the nonce-reuse issue.  pointing to the other security considerations is a good start, but also adding something along the following would do it:

Of particular interest are the security considerations concerning the
use of AES GCM [RFC4106]; AES in GCM mode is vulnerable to catastrophic
forgery attacks if a nonce is ever repeated with a given key.

s3.2: Any thought to also allowing AES-XCBC-PRF-128 [RFC4334] so that if an implementation wanted to be AES only that it could do so?

[Ballot comment]
Like Spencer, I'd like to see the changes agreed by Tom and David to be incorporated, but I trust that the responsible AD will ensure that gets done so no need for me to hold a discuss on it.

s2.2: I think you need to add normative references to [RFC3602] for AES-128-CBC:

OLD:

AES in CBC mode MUST be implemented.  AES CBC implementations
MUST support 128-bit keys and MAY support other key sizes.

NEW:

AES in CBC mode MUST be implemented [RFC3602].  AES CBC
implementations MUST support 128-bit keys and MAY support
other key sizes.

s2.2: r/implement" requirement) ./implement" requirement).
s2.2: r/AES in Counter mode MAY/AES in Counter mode (AES CTR) MAY

s3: Maybe with more teeth:

OLD:

Use of 1024 bit D-H groups with 3DES CBC and HMAC-
SHA1 is no longer recommended,

NEW:

Use of 1024 bit D-H groups with 3DES CBC and HMAC-
SHA1 is NOT RECOMMENDED,

s3: r/use of IPsec v3 is recommended./use of IPsec v3 is RECOMMENDED.  ?

s3.1: Is it worth mentioning the OCSP extension mechanism to check the validity of the certificates?

[Ballot comment]
given the breadth of the changes, I'm not sure why this document doesn't simply obsolete 3723 supplanting it with 3723 text+updates rather than simply enumerating the changes.

[Ballot comment]
I think the resolutions David and Tom Yu arrived at while chatting about Tom's SECDIR review are helpful and support them being in the RFC.

IESG/Authors/WG Chairs:

IANA has reviewed draft-ietf-storm-ipsec-ips-update-03, which is currently in Last Call, and has the following comments:

We understand that, upon approval of this document, there are no IANA
Actions that need completion.

If this assessment is not accurate, please respond as soon as possible.

The following Last Call announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (Securing Block Storage Protocols over IP: RFC 3723 Requirements Update for IPsec v3) to Proposed Standard


The IESG has received a request from the STORage Maintenance WG (storm)
to consider the following document:
- 'Securing Block Storage Protocols over IP: RFC 3723 Requirements Update
  for IPsec v3'
  as Proposed Standard

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf@ietf.org mailing lists by 2013-08-19. Exceptionally, comments may be
sent to iesg@ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract


  RFC 3723 specifies IPsec requirements for block storage protocols
  over IP (e.g., iSCSI) based on IPsec v2 (RFC 2401 and related RFCs);
  those requirements have subsequently been applied to remote direct
  data placement protocols, e.g., RDMAP.  This document updates RFC
  3723's IPsec requirements to IPsec v3 (RFC 4301 and related RFCs) and
  makes some changes to required algorithms based on developments in
  cryptography since RFC 3723 was published.

  [RFC Editor: The "Updates:" list above has been truncated by xml2rfc.
  The complete list is - Updates: 3720, 3723, 3821, 3822, 4018, 4172,
  4173, 4174, 5040, 5041, 5042, 5043, 5044, 5045, 5046, 5047, 5048 (if
  approved) ]




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-storm-ipsec-ips-update/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-storm-ipsec-ips-update/ballot/


No IPR declarations have been submitted directly on this I-D.

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)?  Why
is this the proper type of RFC?  Is this type of RFC indicated in the
title page header?

  Proposed Standard RFC is requested because this document updates
  RFC 3723, a Proposed Standard RFC as well as multiple additional
  Proposed Standard RFCs.  Standards Track is indicated as the
  intended status in the title page header.

(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:

Technical Summary

  RFC 3723 specifies IPsec requirements for block storage protocols
  over IP (e.g., iSCSI) based on IPsec v2 (RFC 2401 and related RFCs);
  those requirements have subsequently been applied to remote direct
  data placement protocols, e.g., RDMAP.  This document updates RFC
  3723's IPsec requirements to IPsec v3 (RFC 4301 and related RFCs) and
  makes some changes to required algorithms based on developments in
  cryptography since RFC 3723 was published.

Working Group Summary

  This document updates the IPsec requirements in RFC 3723 and all RFCs
  to which those requirements apply.  The iSCSI maintenance work in
  the storm WG had originally intended to only update the IPsec
  requirements for iSCSI.  Two developments changed this approach:

  o Cryptographic developments upended RFC 3723's requirement for 3DES
    as the mandatory to implement encryption transform.  The protocols
    to which RFC 3723 applies can approach 3DES's birthday bound and
    need to rekey in less than a minute on high-speed links.

  o iSER (iSCSI extensions for RDMA) uses RFC 3723 IPsec requirements
    twice, once for iSCSI and once for the underlying rddp (iWARP)
    RDMA protocol.  An RFC 3723 update is needed for the latter in
    order to avoid inconsistent IPsec requirements in the same protocol
    stack.

  David McGrew and Steve Kent (respectively) deserve credit for surfacing
  the above two concerns that lead to creation of this document.  This
  document has not been controversial in the storm WG.

Document Quality

  This document specifies a profile of widely implemented protocols,
  IPsec v2 and v3.  The specified cryptographic transforms have been
  selected as ones that are commonly available in IPsec implementations.

  Sean Turner (SEC AD) and Paul Hoffman (ipsecme WG chair) were both
  notably helpful in providing advice on transform selection.  Yaron
  Sheffer (ipsecme WG chair) provided a thorough review that significantly
  improved the quality of this document.  Tom Talpey (storm WG chair)
  provided a thorough WG Last Call review.

  The document shepherd is very pleased with the help received from
  both ipsecme WG co-chairs and the AD responsible for the ipsecme WG.

Personnel

  Document Shepherd: David Black (storm WG co-chair)
  Responsible Area Director: Martin Stiemerling (Transport)

(3) Briefly describe the review of this document that was performed by
the Document Shepherd.  If this version of the document is not ready
for publication, please explain why the document is being forwarded to
the IESG.

  The Document Shepherd is the primary editor of this document, and
  has reviewed its text in detail, most recently in dealing with WG
  Last Call comments.  The Document Shepherd believes that this
  document is ready for RFC publication.

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed? 

  No.

(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization?

  No.

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.

  None.

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP 78
and BCP 79 have already been filed. If not, explain why.

  Yes.

(8) Has an IPR disclosure been filed that references this document?

  No.

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others
being silent, or does the WG as a whole understand and agree with it? 

  The storm (STORage Maintenance) WG is a maintenance WG that works on
  a number of storage technologies, and hence not every participant is
  interested in every technology.  The members of the WG who are
  interested in the application of IPsec to the WG's protocols
  understand and agree with this document.

(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent?

  No.

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

  idnits 2.12.17 finds a number of things to complain about, none of
  which are actual problems:

  - The IPsec v2 RFCs are necessary normative references, even though
they have obsolete status.
  - There is no point in repeating the long list of updated RFCs
      in the abstract.
  - idnits warns about possible content from before 10 November 2008;
      there is no such content.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

  Not applicable.

(13) Have all references within this document been identified as
either normative or informative?

  Yes.

(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state?

  No.  There are normative references to two Internet-Drafts.  One of
  them (iSER) is aleady in the RFC Editor's Queue and the other (iSCSI
  Consolidated) is expected to join it there shortly.

(15) Are there downward normative references references (see RFC 3967)?

  No.

(16) Will publication of this document change the status of any
existing RFCs? Are those RFCs listed on the title page header, listed
in the abstract, and discussed in the introduction? If the RFCs are not
listed in the Abstract and Introduction, explain why, and point to the
part of the document where the relationship of this document to the
other RFCs is discussed. If this information is not in the document,
explain why the WG considers it unnecessary.

  This document does not change the status of any RFCs.  The updated
  RFCs are discussed in the document.

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly identified.
Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).

  Not applicable; this document has no IANA considerations.

(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find
useful in selecting the IANA Experts for these new registries.

  Not applicable.

(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.

  Not applicable.