Re: I-D ACTION:draft-jabley-ipv6-rh0-is-evil-00.txt

Le 11 mai 07 à 04:24, JINMEI Tatuya / 神明達哉 a écrit :

> Are you suggesting the following part should apply regardless of the
> type of routing header?
>
>   In particular, the value of the Segments Left field
>   MUST not be considered.
>
> If so, I don't think the current rh0 draft could be interpreted that
> way (aside from whether we'd agree it in the first place).

Nope. I just said it was in contradiction (meaning it updated the
specification) with the following part of section 4.4 of RFC 2460:

       If Segments Left is zero, the node must ignore the Routing header
       and proceed to process the next header in the packet, whose type
       is identified by the Next Header field in the Routing header.

       If Segments Left is non-zero, the node must discard the packet  
and
       send an ICMP Parameter Problem, Code 0, message to the packet's
       Source Address, pointing to the unrecognized Routing Type.

as updated system will have to protect themselves from the remaining
source routed packets bounced by unpatched waypoints that still forward
RH0. RH0 will be a specific RH type for which stacks will not look at
the Segments Left field to select the behavior (meaning will not end
processing the UL if Segments Left is 0).

By the way, for the proposal of replying with an ICMPv6 message for RH0
packets whose destination address in the main IPv6 header is one of the
node, I think it's fair to do it independently of Segments Left field,
i.e. as soon as the type is 0 (better said than let implicit).

a+

-- Arnaud Ebalard
EADS Innovation Works - IT Sec Research Engineer
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