Subject: Roman Danyliw's No Objection on draft-ietf-6man-grand-05: (with COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Tue, 29 Jun 2021 13:44:33 -0700

Roman Danyliw has entered the following ballot position for
draft-ietf-6man-grand-05: No Objection

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COMMENT:
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Thank you to Scott Kelly for the SECDIR review.

** Section 5.3.  Does the outcome of any of the documented scenarios change if
the host has DAD turned off (per Section 5.3.1, Step #4 and Section 5.3.2, Step
#5)

** Section 10.  It would be useful to reiterate with a back reference the
unlikely, but possible condition where the duplicated address temporarily gets
the traffic from the rightful owner (noted in Section 5.3.2).

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From: Jen Linkova <[email-masked]>
Date: Wed, 30 Jun 2021 18:00:02 +1000

Hi Roman,

> the host has DAD turned off (per Section 5.3.1, Step #4 and Section 5.3.2, Step

I've added the following text to the end of the section 5;
"The analysis assumes that the host performs Duplicate Address
Detection, as section 5.4 of [RFC4862] requires that DAD MUST be
performed on all unicast addresses prior to assigning them to an
interface."

> the traffic from the rightful owner (noted in Section 5.3.2).

I've added the following text, please let me know if it doesn't
address your concern:

"Section 5 describes some corner cases when a host with the duplicated
Optimistic address might get some packets intended for the rightful
owner of the address. However such scenarios do not introduce any new
attack vectors: even without the proposed changes, an attacker can
easily override the routers neighbor cache and redirect the traffic by
sending NAs with the Solicited flag set."

-- 
SY, Jen Linkova aka Furry