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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Tue, 20 Dec 2016 04:14:06 +0100
Message-ID: <CAHmME9rDK0MEFH2oOVjeTF0n=J6=Hsk9e5Hyj2GDnFk8V3LtwA@mail.gmail.com>
Subject: Re: openwrt route_allowed_ips is inprecise
To: Baptiste Jonglez <baptiste@bitsofnetworks.org>
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Hey Baptiste,

On Tue, Dec 20, 2016 at 2:13 AM, Baptiste Jonglez
<baptiste@bitsofnetworks.org> wrote:

> By the way, besides the issue of magic, this approach seems incorrect
> depending on the order of the routes.  Consider the case where cmd_add()
> handles the following sequence of allowed-ips:
>
>     10.0.0.0/8   dev wg0
>     10.4.7.0/24  dev wg0
>     10.4.0.0/16  dev wg1
>
> Your method would incorrectly drop the second route, and then the third
> route would take over traffic for this /24 through the wrong interface.

Very smart point and astute observation! This should be fixed here:

https://git.zx2c4.com/WireGuard/commit/?id=5838c950859f1b55ad344e81b77a0b71917ffd61

Unless there are objections, that will ship with the next snapshot.

Jason