Re: Linux IPv6 DAD not full conform to RFC 4862 ?

From: YOSHIFUJI Hideaki / 吉藤英明 <redacted>
Date: Thu, 10 Jan 2008 08:46:55 +0900 (JST)

In article [ref] (at Wed, 09 Jan 2008 15:32:12 -0800 (PST)), David Miller [off-list ref] says:

quoted

I question any RFC mandate that shuts down IP communication on a node
because of packets received from remote systems.

RFC4862 tell us that we SHOULD disable IP communication.
(IP means IPv6 here; IPv4 is out of scope.)
In IETF term, a SHOULD is almost a MUST.  We are required to follow
unless we have very good reason to ignore it.

A DoS by definition is a very good reason.

quoted

If the TAHI test can trigger this, so can a compromised system on your
network and won't that be fun? :-)

So, I know the specification, but I have ignored it.
I think it is fine to implent in some way, but I do think we must have
a switch not to do this.

Because of the above, the existing behavior must still stay the
default.  I hope this is your plan.

By default Linux will not implement this SHOULD, it's a security
issue.

I more and more do not like these conformance tests, they leave no
room whatsoever for handling bugs or ill-specified features in the
specification.