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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Thu, 21 Sep 2017 14:54:25 +0200
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Subject: Re: [wireguard-dev] Ability to use one udp port for multiple wg
 interfaces
To: nicolas prochazka <prochazka.nicolas@gmail.com>
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Perhaps I'm not understanding your last message, but it's most
certainly possible to bind to a particular IP address with a service.
It's also possible to bind to _all_ IP addresses, and then use
iptables to control which source networks have access to a particular
port. Finally, within a service, if you only allow input from wg0
since allowed-ips gives strong cryptographic binding, you can
explicitly filter on the IP addresses you get from recvfrom.

I don't understand your meaning of "internal dev".