Re: "notification events for routing changes" patch

[Murat Sezgin <msezgin@codeaurora.org>]

Yes I know about the merged code. It works well for the regular linux
network traffic, but as I said in my email, if the traffic is offloaded
from the linux networking stack, the subsequent flows, after the route
change, will never seen by the iptables_nat modules, so the conntarck
entry cannot be killed.

Thanks,
Murat

On 11/17/15, 12:28 AM, "Jozsef Kadlecsik" <kadlec@blackhole.kfki.hu> wrote:

>On Mon, 16 Nov 2015, Murat Sezgin wrote:
>
>> While I was looking for a solution in the kernel for general routing
>> change notification implementation, I came across your following patch.
>> 
>> http://www.spinics.net/lists/netfilter-devel/msg24239.html
>> 
>> In this email chain, you said that you found another simple solution and
>> implemented it in the masquerade module. I saw that commit in the
>>upstream
>> kernel.
>> 
>> But I think the patch you proposed before also very useful for the fast
>> path implementations. Because when a connection starts to flow through
>>the
>> fast path, linux networking stack no longer sees those packets. Then, if
>> the route table is changed in some way, let?s say user add/delete a
>>route
>> with the ?route? or ?ip route? command, the fast path traffic will not
>> aware of this change. So, if we have a notification mechanism like you
>> have implemented, the fast path manager module can register itself to
>> these events and manage its connections accordingly.
>> 
>> Do you have any plan to push and merge this path to the upstream kernel?
>
>No, the patch was inefficient from conntrack point of view and finally
>the 
>patch "Handle routing changes in MASQUERADE target, v4" went into the
>kernel:
>
>http://www.spinics.net/lists/netfilter-devel/msg24276.html
>
>Best regards,
>Jozsef
>-
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