From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 94C37C433B4 for ; Tue, 20 Apr 2021 04:52:27 +0000 (UTC) Received: from lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B85AF613AE for ; Tue, 20 Apr 2021 04:52:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B85AF613AE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=crfreenet.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=wireguard-bounces@lists.zx2c4.com Received: by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 55cb0ff5; Tue, 20 Apr 2021 04:52:23 +0000 (UTC) Received: from mail.crfreenet.org (varda.crfreenet.org [185.133.240.16]) by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 0350db21 for ; Mon, 19 Apr 2021 13:04:06 +0000 (UTC) Received: from feanor (slizka.chapadla.cz [93.99.228.74]) by mail.crfreenet.org (Postfix) with ESMTP id A41E6112A90; Mon, 19 Apr 2021 15:04:04 +0200 (CEST) Date: Mon, 19 Apr 2021 15:03:54 +0200 From: Ondrej Zajicek To: Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= Cc: bird-users@network.cz, wireguard@lists.zx2c4.com, Stefan Haller Subject: Re: [PATCH] babel: Drop check for IF_MULTICAST interface flag Message-ID: References: <20210415134450.197661-1-toke@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20210415134450.197661-1-toke@toke.dk> X-Operating-System: Debian GNU/Linux X-Mailman-Approved-At: Tue, 20 Apr 2021 04:52:21 +0000 X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" On Thu, Apr 15, 2021 at 03:44:50PM +0200, Toke H=F8iland-J=F8rgensen wrote: > The babel protocol code was checking interfaces for the IF_MULTICAST flag > and refusing to run if this isn't present. However, there are cases where > this flag doesn't correspond to the actual capability of sending multicast > packets. For instance, Wireguard interfaces on FreeBSD doesn't set the > required flags, but Babel will run just fine over such an interface given > the right configuration. Hi Is there a reason why to disregard the IF_MULTICAST flag? This seems to me more like a bug in FreeBSD Wireguard implementation that should be fixed there. Is this flag properly checked on Linux, or is there some reason why the flag is missing? Routing protocols in BIRD generally follow this flag (and perhaps use it to switch to unicast-only mode), so i do not see why Babel should behave differently. --=20 Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."