From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: david.w.cowden@gmail.com Received: from krantz.zx2c4.com (localhost [127.0.0.1]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 40bc124e for ; Sat, 8 Sep 2018 04:45:05 +0000 (UTC) Received: from mail-pl1-x62b.google.com (mail-pl1-x62b.google.com [IPv6:2607:f8b0:4864:20::62b]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 08fc43f9 for ; Sat, 8 Sep 2018 04:45:05 +0000 (UTC) Received: by mail-pl1-x62b.google.com with SMTP id f1-v6so7435963plt.4 for ; Fri, 07 Sep 2018 21:45:31 -0700 (PDT) Return-Path: Received: from dcx1.dcow.io (eero.static.monkeybrains.net. [199.116.72.162]) by smtp.gmail.com with ESMTPSA id y69-v6sm19775216pfd.36.2018.09.07.21.45.29 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 07 Sep 2018 21:45:29 -0700 (PDT) Date: Fri, 7 Sep 2018 21:45:27 -0700 From: David Cowden To: wireguard@lists.zx2c4.com Subject: Broadcasts over L3 tunnel Message-ID: <20180908044527.7dhejnj2yp257pdt@dcx1.dcow.io> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , I've been playing around with wireguard and I'd really like to enable a scenario where a remote peer appears like they're on a LAN (at L3) somewhere so that e.g. mDNS broadcasts reach the remote peer. I can create all sorts of topologies where traffic can flow between the remote peer(s) and the LAN peers, but I'm hung up on getting the kernel to send broadcasts to the wireguard interface. If you put everything on the same subnet, you essentially end up with two conflicting entries in the LAN host's routing table: one that routes LAN traffic to the gateway for egress or if you're running on the gateway then egresses upstream, and a second entry telling the kernel that the same subnet is available across the wg interface. Is a topology like this possible without hacking up some facade into L2? David