Re: ICMPv6 Redirects

[Alexander Aring <alex.aring@gmail.com>]

On Tue, Sep 30, 2014 at 01:13:24PM +0200, Alexander Aring wrote:
> Hi Jukka,
> 
> On Tue, Sep 30, 2014 at 01:55:14PM +0300, Jukka Rissanen wrote:
> > Hi Alex,
> > 
> > On ti, 2014-09-30 at 12:03 +0200, Alexander Aring wrote:
> > > On Tue, Sep 30, 2014 at 03:23:09PM +0530, Varka Bhadram wrote:
> > > > On 09/30/2014 03:13 PM, Alexander Aring wrote:
> > > > >
> > > > >>May be IEEE-802.11 packets send to IPv6 Layer. In that case Its not dead code.
> > > > >>
> > > > >
> > > > >802.11 data frames will be converted to ethernet frames.
> > > > >
> > > > >Why we now talking about 802.11? 6LoWPAN set always PACKET_HOST and then
> > > > >we never have PACKET_BROADCAST set in IPv6 Layer. Then matching pkt_type
> > > > >with PACKET_BROADCAST is dead code.
> > > > 
> > > > We don't know in which scenario the IPv6 Layer checking that statement.
> > > > 
> > > > The control is reaching there when they got ICMPv6 message of typeICMPV6_MGM_REPORT  <http://lxr.free-electrons.com/ident?i=ICMPV6_MGM_REPORT>  [1] .
> > > > 
> > > > We don't know the significance of it..??
> > > > 
> > > 
> > > Yep, we don't know it and it doesn't matter, but override the pkt_type
> > > to PACKET_HOST when we have a broadcast frame is wrong.
> > > 
> > > Broadcast means it's IPv6 BROADCAST or MULTICAST, the detection if
> > > LOGICAL MULTICAST over BROADCAST xor BROADCAST over BROADCAST is IPv6 Layer.
> > 
> > I probably missed something from earlier mails but why are we talking
> > about broadcast with IPv6? After all IPv6 supports only multicast and
> > broadcasting is not supported.
> 
> The issue what we talking about is:
> 

In a nutshell:

We have issues at [1] and [3] because [0]. For better performance we
should something do like [1] at 6LoWPAN packet receive function for
example [2].

:-)

- Alex

[0] http://git.kernel.org/cgit/linux/kernel/git/bluetooth/bluetooth-next.git/tree/net/6lowpan/iphc.c?id=f19f4f9525cf32f97341fac20ce66392e86a1b67#n192
[1] http://lxr.free-electrons.com/source/net/ipv6/ip6_input.c#L72
[2] http://lxr.free-electrons.com/source/net/ieee802154/6lowpan_rtnl.c#L465
[3] http://lxr.free-electrons.com/source/net/ipv6/mcast.c#L1413