Hi Roman,

Discussion on discuss.

From: Alvaro Retana <[email protected]>
Date: Wednesday, August 21, 2019 at 11:11 AM
To: "[email protected]" <[email protected]>
Cc: Roman Danyliw <[email protected]>, Stephane Litkowski 
<[email protected]>, "[email protected]" <[email protected]>, 
"[email protected]" <[email protected]>, The IESG <[email protected]>
Subject: Roman Danyliw’s DISCUSS on draft-ietf-ospf-yang-26
Resent-From: <[email protected]>
Resent-To: Yingzhen Qu <[email protected]>, Christian Hopps 
<[email protected]>, Acee Lindem <[email protected]>
Resent-Date: Wednesday, August 21, 2019 at 11:08 AM

[It looks like the datatracker didn’t send out the text to Roman’s DISCUSS.  I 
didn’t receive it, nor do I see it in the mail archive.  So I’m pasting it 
here. — Alvaro.]

- - - - - - - - - - -
DISCUSS
- - - - - - - - - - -

A “discuss to discuss”.  Per the convention outlined in 
https://trac.ietf.org/trac/ops/wiki/yang-security-guidelines, thank you for 
clearly noting the implication of not securing these nodes properly.

Furthermore, following the convention, I would have expected Section 4 to have 
enumerated the sensitive writeable/creatable/deletable data nodes; and the 
sensitive readable nodes individually.  For a model this large, I can imagine 
that individual enumeration would be a long list.

It doesn’t make sense to talk about every configurable leaf so the section 
describes the general problems that can ensue if OSPF protocol configuration is 
compromised. We could go into classes of writeable nodes but I question what 
benefit that would actually have.


In the case of read operations, the text opens with saying that “some of the 
readable data nodes ...” and later says “The exposure of the ... LSDB will 
expose the detailed topology ...”.  Can you help me understand which part of 
ietf-ospf.yang is the LSDB and which parts refer to “some of the readable 
nodes”?  Is there are a difference, or is this text asserting that all parts of 
the modules are sensitive and need access control?

The LSDB refers to the instance, area, virtual link, sham-link, and interface 
Link State DataBases (LSDB).

             /ospf/database
            /ospf/areas/area[area-id]/database
            /ospf/virtual-links/virtual-link[transit-area-id router-id]/database
            /ospf/areas/area[area-id]/interfaces/interface[name]/database
            /ospf/area/area[area-id]/sham-links/sham-link[local-id 
remote-id]/database

All parts are sensitive. The LSDB is more so since it gives visibility beyond 
the network device itself.



A related line of questioning for the write operation.  The text opens with 
saying that “There are a number of data nodes defined in ietf-ospf.yang ... 
[and that] [w]rite operations ... to these nodes without proper protection can 
have a negative effect on the network operations ... [and] ... the ability to 
modify OSPF configuration ...” is problematic.  Can you help me understand 
which parts of the text is the “OSPF configuration” vs. “there are number of 
data nodes ...”?  If there isn’t a different, is the text asserting that all 
parts of the modules are sensitive and need access control?

This is alludes to the “config true” nodes which comprise OSPF configuration. I 
guess this is a repeat of your first comment.

Thanks,
Acee


- - - - - - - - - - -
COMMENT
- - - - - - - - - - -

(1) Idnits returned a seemingly valid few reference issues:

  ** Downref: Normative reference to an Experimental RFC: RFC 1765

  ** Downref: Normative reference to an Experimental RFC: RFC 4973

(2) Editorial
-- Section 4.  Isn’t RFC8341, “the Network Configuration Access Control Model” 
rather than the “NETCONF access control model”?

-- Section 4.  Typo.  s/specificationn/specification/

-- Section 4.  Remove the duplicate instance of the phrase “for legacy 
implementations that do not support key-chains”.

-- Section 4.  Typo.  s/The OSPF YANG module support/the OSPF YANG module 
supports/

Alvaro Retana
_______________________________________________
Lsr mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lsr

Reply via email to