Re: [PATCH net v3] vti: fix spd lookup: match plaintext pkt, not ipsec pkt

[David Miller <davem@davemloft.net>]

From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Thu, 7 Nov 2013 12:25:49 +0100

> On Wed, Nov 06, 2013 at 09:05:53AM +0100, Christophe Gouault wrote:
>> The vti interface inbound and outbound SPD lookups are based on the
>> ipsec packet instead of the plaintext packet.
>> 
>> Not only is it counterintuitive, it also restricts vti interfaces
>> to a single policy (whose selector must match the tunnel local and
>> remote addresses).
>> 
>> The policy selector is supposed to match the plaintext packet, before
>> encryption or after decryption.
>> 
>> This patch performs the SPD lookup based on the plaintext packet. It
>> enables to create several polices bound to the vti interface (via a
>> mark equal to the vti interface okey).
>> 
>> It remains possible to apply the same policy to all packets entering
>> the vti interface, by setting an any-to-any selector (src 0.0.0.0/0
>> dst 0.0.0.0/0 proto any mark OKEY).
>> 
>> Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
> 
> Hm, this patch breaks my current vti test setup. I would need to
> configure the policies and states dependent on the kernel version
> if we apply this patch...
> 
> It would be good to hear from the original author of the vti code
> whether the current behaviour is intentional before we do anything
> here.

I'm disappointed that we're breaking IPSEC semantics several times.
This really isn't acceptable at all, not even remotely.

The fact that a developer has a configuration he was actually
using, and would be broken by this patch, says to me that there
is absolutely no way I can apply this.

Sorry.