Subject: [lisp] Roman Danyliw's No Objection on draft-ietf-lisp-gpe-17: (with COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Wed, 08 Jul 2020 15:08:00 -0700

Roman Danyliw has entered the following ballot position for
draft-ietf-lisp-gpe-17: No Objection

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COMMENT:
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Section 4.  Per “When a LISP-GPE router performs Ethernet encapsulation, the
inner header 802.1Q [IEEE.802.1Q_2014] VLAN Identifier (VID) MAY be mapped to,
or used to determine the LISP Instance IDentifier (IID) field”, as noted in a
DISCUSS item in my ballot on draft-ietf-lisp-rfc6830bis-32, using Instance ID
values as 802.1Q tags without integrity protection seems problematic in the
public internet scenario.  Please add cautionary language recommending
integrity protection.

Section 7.  Per “LISP-GPE, as many encapsulations that use optional extensions,
is subject to on-path adversaries that by manipulating the P-Bit and the packet
itself can remove part of the payload or claim to encapsulate any protocol
payload type”, it’s worse than that – (in the absence of integrity protection
and like LISP in general) an on-path attacker make arbitrary modifications to
the packet (like a 802.1Q tag in the encapsulated ethernet; or the Instance ID
using an 802.1.Q tag)

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From: "Fabio Maino (fmaino)" <[email-masked]>
Date: Mon, 27 Jul 2020 05:20:36 +0000

Hi Roman, 
Thanks for your review. 

We have added the following sentence at the end of section 4.4: 

   "Refer to Section 7 for consideration about the use of integrity
   protection for deployments, such as the public Internet, concerned
   with on-path attackers."

And changed section 7 into: 

   "LISP-GPE, as many encapsulations that use optional extensions, is
   subject to on-path adversaries that can make arbitrary modifications
   to the packet (including the P-Bit) to change or remove any part of
   the payload, or claim to encapsulate any protocol payload type.
   Typical integrity protection mechanisms (such as IPsec) SHOULD be
   used in combination with LISP-GPE by those protocol extensions that
   want to protect from on-path attackers."

Diffs with rev -18 are attached. 

Thanks,
Fabio

On 7/8/20, 3:08 PM, "Roman Danyliw via Datatracker" <[email-masked]> wrote: