Re: [I2nsf] Fwd: [Last-Call] New Version Notification for draft-ietf-i2nsf-sdn-ipsec-flow-protection-11.txt

tom petch <daedulus@btconnect.com> Wed, 28 October 2020 18:02 UTC

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To: Rafa Marin-Lopez <rafa@um.es>
References: <160337357077.29083.9236626834026808055@ietfa.amsl.com> <EE5AB669-73BB-4517-A6F4-23B7807FB36E@um.es> <5F9815D1.9010303@btconnect.com> <DDE550B1-9A9E-4954-B6F9-C0A33ECE1275@um.es>
Cc: i2nsf@ietf.org, Gabriel Lopez <gabilm@um.es>, Fernando Pereniguez-Garcia <fernando.pereniguez@cud.upct.es>, last-call@ietf.org, ynir.ietf@gmail.com
From: tom petch <daedulus@btconnect.com>
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Subject: Re: [I2nsf] Fwd: [Last-Call] New Version Notification for draft-ietf-i2nsf-sdn-ipsec-flow-protection-11.txt
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On 28/10/2020 10:42, Rafa Marin-Lopez wrote:
> Hi Tom:
>
> Thank you very much for your insight. It is very helpful. Please see our comments/questions inline.
>
>> El 27 oct 2020, a las 13:42, tom petch <daedulus@btconnect.com> escribió:
>>
>> I think that the IESG will find a number of problems with this I-D.
>>
>> YANG module references RFC822 which is several years out of date

Rafa

On boiler plate, I mean the reference to RFC2119 which now must use the 
language from RFC8174 in the body of the I-D; sorry for the confusion.

On XXXX, you have XXXX standing in for more than one RFC-to-be which 
confuses.  The convention is to use XXXX for this I-D and then AAAA BBBB 
etc for any others such as the netconf I-D in this instance.

Two big issues, for me (perhaps not for others).  The convention with 
YANG is for each successive line to be indented two characters, you have 
four, which creates a lot of white space and pushes the text to the 
right hand margin.  I think that two characters is the default when you 
use pyang to format a YANG module.

And references.  I have had to work harder than I want to to make sense 
of the IANA references.  I think you should have five separate 
references in the I-D for IANA for
Transform Type 1
Transform Type 3
Transform Type 4
Authentication Method
Protocol Numbers
and each reference in the I-D should have a URL pointing to the specific 
section of IANA web site.
In the YANG, it is harder to know what to do.  Those first three 
references are in the third tier i.e.
Group - Internet Key Exchange V2 (IKEv2) Parameters
Registry  -Transform Attribute Types
and then Type 1, 3, 4 as the third tier as I am calling it
and I think that every reference in the YANG should give me all three 
tiers after IANA in that order perhaps
IANA; IKEv2 Parameters; Transform Atribute Types; Transform Type 1
If the syntax needs tweeking, then the RFC Editor will do a good job of 
that but at present the references are inconsistent in which elements 
are specified in what order and that is something the RFC Editor 
probably cannot cope with.
Authentication Method is a registry so that just needs Group name and 
Registry name after IANA.

Some minor glitches.
I-D appears twice in the body of the I-D - perhaps document or memo.
objetives/objectives/
end port number perhaps /must/MUST/
and YANG is very good at including such checks with a must ....
'If AEAD is used .. where? this occurs in several places and I think 
that you need to specify the leaf where AEAD will be specified or implied.
And is it possible to make that a YANG 'must' statement - looking at the 
IKEv2 registries it is not obvious which are AEAD so that might be more 
complexity than it is worth.
'only available on linux kernels' Um implementation detail, you may get 
asked to remove that altogether or at least to a Informative Appendix - 
I would leave it in for now.
'import ietf-i2nsf-ikec' the reference needs to be to a RFC and if it is 
not yet an RFC then RFC XXXX <title> in both Appendix B and C
leaf-list pfs-groups could do with a reference - Transform Type 4?

I am still working my way through the YANG so may have some more 
comments tomorrow.

Tom Petch














> We have realized that we missed to change this, even though we discussed it. We will change it right away in the following way (bold):
>
> case rfc822-address-string {
>       leaf rfc822-address-string {
>            type string;
>            description
>                "Specifies the identity as a
>                 fully-qualified RFC5322 email
>                 address string. An example is,
>                 jsmith@example.com. The string
>                 MUST NOT contain any
>                 terminators e.g., NULL, CR,
>                 etc.).";
>             reference
>                    "RFC 5322.";
>       }
> }
>
> Btw, we already used in the past “case rfc822-address-string” and “leaf rfc822-address-string” since this is coming from IKEv2 standard. Do you think we should change that name as well?
>
>
>>
>> YANG module references IANA Protocol Numbers which is not in the I-D references
>
> We have included the following reference:
>
> [IANA-Protocols-Number]
>                Internet Assigned Numbers Authority (IANA), "Protocol
>                Numbers", January 2020.
>
>
>>
>> s.2 boiler plate is out of date
>
> What we see is the I-D has the second choice stated in https://www.ietf.org/standards/ids/guidelines/
>
> This Internet-Draft is submitted in full conformance with the
>     provisions of BCP 78 and BCP 79.
>
>     Internet-Drafts are working documents of the Internet Engineering
>     Task Force (IETF).  Note that other groups may also distribute
>     working documents as Internet-Drafts.  The list of current Internet-
>     Drafts is at https://datatracker.ietf.org/drafts/current/.
>
>     Internet-Drafts are draft documents valid for a maximum of six months
>     and may be updated, replaced, or obsoleted by other documents at any
>     time.  It is inappropriate to use Internet-Drafts as reference
>     material or to cite them other than as "work in progress."
>
> Could you refer what is out of date?
>
>>
>> XXXX is standing in for more than one RFC
>
> Yes, XXXX has been used because we do not know the future number assigned to our I-D.
>
> Also we realized we also included this to refer to crypto-types I-D but this has been solved now in a new version -12 that we are preparing to include your comments. We noticed we can replace the type of rw cert-data?, ca-data*, crl-data? for binary without any problem.
>
> |           |     +--rw cert-data?        binary
> |           +--rw private-key?            binary
> |           +--rw ca-data*                binary
> |           +--rw crl-data?               binary
>
>>
>> but the show stopper that makes a proper review of this too costly is the references.  Those to IANA of which there are several I want to pursue.  The I-D reference is to IKEv2 parameters. Sadly, this is a three tier structure and noone agrees on what to call the third tier so I will call it tier3 here.  Top level is Group, as per RFC8126, second level is Registry.  The I-D reference is to the Group only which is fine if the actual reference then specifies the Registry and Tier3 but they never do, usually just Tier3 e.g. Transform Type 3 which makes for a lot of work for the reader, too much for this one.  You have to go hunting in all the second level Registry until you can find a match for the Tier3 identifier. And there are no URL.  If you want an example that I find easy to use, go look at RFC8407 (as usual).
>
> You’re right. Could you point the exact part at RFC 8407 with that example? We would really appreciate it.
>
> On the other hand, would it be enough to include the URL for Transform Type 3 https://www.iana.org/assignments/ikev2-parameters/ikev2-parameters.xhtml#ikev2-parameters-7 ?
>
> (Same for Transform Type 1, Transform Type 4)
>
>>
>> The reference for import of i2nsf-ikec gives a YANG module name; this needs to be the name of the RFC to be
>
> Fixed.
>
> import ietf-i2nsf-ikec {
>              prefix nsfikec;
>              reference
>                  "RFC XXXX: Software-Defined Networking
>                 (SDN)-based IPsec Flow Protection.";
> }
>
> We still use XXXX because we do not know the number assigned to the RFC to be.
>
>>
>> The example IPv6 address in the YANG module has :0:0: which is usually just ::
>
> Fixed.
>
> If you have any further comments, please let us know so we can include them in -12
>
> Best Regards.
>>
>> And I have some way to go still.
>>
>> Tom Petch
>>
>> On 22/10/2020 18:39, Rafa Marin-Lopez wrote:
>>> Dear all:
>>>
>>> After receiving a suggestion to make things clearer in the feature ikeless-notification description, we have just uploaded a new version -11 with a minor change to add the following text:
>>>
>>> feature ikeless-notification {
>>>              description
>>>                  "This feature indicates that the server supports
>>>                  generating notifications in the ikeless module.
>>>
>>>                  To ensure broader applicability of this module,
>>>                  the notifications are marked as a feature.
>>>                  For the implementation of ikeless case,
>>>                  the NSF is expected to implement this
>>>                  feature.";
>>>          }
>>>
>>> Best Regards.
>>>
>>>> Inicio del mensaje reenviado:
>>>>
>>>> De: internet-drafts@ietf.org
>>>> Asunto: New Version Notification for draft-ietf-i2nsf-sdn-ipsec-flow-protection-11.txt
>>>> Fecha: 22 de octubre de 2020, 15:32:50 CEST
>>>> Para: "Fernando Pereniguez-Garcia" <fernando.pereniguez@cud.upct.es>, "Rafael Lopez" <rafa@um.es>, "Gabriel Lopez-Millan" <gabilm@um.es>, "Rafa Marin-Lopez" <rafa@um.es>
>>>>
>>>>
>>>> A new version of I-D, draft-ietf-i2nsf-sdn-ipsec-flow-protection-11.txt
>>>> has been successfully submitted by Rafa Marin-Lopez and posted to the
>>>> IETF repository.
>>>>
>>>> Name:		draft-ietf-i2nsf-sdn-ipsec-flow-protection
>>>> Revision:	11
>>>> Title:		Software-Defined Networking (SDN)-based IPsec Flow Protection
>>>> Document date:	2020-10-22
>>>> Group:		i2nsf
>>>> Pages:		92
>>>> URL:            https://www.ietf.org/archive/id/draft-ietf-i2nsf-sdn-ipsec-flow-protection-11.txt
>>>> Status:         https://datatracker.ietf.org/doc/draft-ietf-i2nsf-sdn-ipsec-flow-protection/
>>>> Htmlized:       https://datatracker.ietf.org/doc/html/draft-ietf-i2nsf-sdn-ipsec-flow-protection
>>>> Htmlized:       https://tools.ietf.org/html/draft-ietf-i2nsf-sdn-ipsec-flow-protection-11
>>>> Diff:           https://www.ietf.org/rfcdiff?url2=draft-ietf-i2nsf-sdn-ipsec-flow-protection-11
>>>>
>>>> Abstract:
>>>>    This document describes how to provide IPsec-based flow protection
>>>>    (integrity and confidentiality) by means of an Interface to Network
>>>>    Security Function (I2NSF) controller.  It considers two main well-
>>>>    known scenarios in IPsec: (i) gateway-to-gateway and (ii) host-to-
>>>>    host.  The service described in this document allows the
>>>>    configuration and monitoring of IPsec Security Associations (SAs)
>>>>    from a I2NSF Controller to one or several flow-based Network Security
>>>>    Functions (NSFs) that rely on IPsec to protect data traffic.
>>>>
>>>>    The document focuses on the I2NSF NSF-facing interface by providing
>>>>    YANG data models for configuring the IPsec databases (SPD, SAD, PAD)
>>>>    and IKEv2.  This allows IPsec SA establishment with minimal
>>>>    intervention by the network administrator.  It does not define any
>>>>    new protocol.
>>>>
>>>>
>>>>
>>>>
>>>> Please note that it may take a couple of minutes from the time of submission
>>>> until the htmlized version and diff are available at tools.ietf.org.
>>>>
>>>> The IETF Secretariat
>>>>
>>>>
>>>
>>> -------------------------------------------------------
>>> Rafa Marin-Lopez, PhD
>>> Dept. Information and Communications Engineering (DIIC)
>>> Faculty of Computer Science-University of Murcia
>>> 30100 Murcia - Spain
>>> Telf: +34868888501 Fax: +34868884151 e-mail: rafa@um.es
>>> -------------------------------------------------------
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>
> -------------------------------------------------------
> Rafa Marin-Lopez, PhD
> Dept. Information and Communications Engineering (DIIC)
> Faculty of Computer Science-University of Murcia
> 30100 Murcia - Spain
> Telf: +34868888501 Fax: +34868884151 e-mail: rafa@um.es
> -------------------------------------------------------
>
>
>
>
>