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 Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 77FF5C433EF for ; Mon, 17 Jan 2022 10:25:00 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 14CA86079E; Mon, 17 Jan 2022 10:25:00 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xXRdNQYVXef3; Mon, 17 Jan 2022 10:24:59 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by smtp3.osuosl.org (Postfix) with ESMTP id 4A241605BE; Mon, 17 Jan 2022 10:24:58 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by ash.osuosl.org (Postfix) with ESMTP id D24981BF3D7 for ; Mon, 17 Jan 2022 10:24:55 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id CE5E5605BE for ; Mon, 17 Jan 2022 10:24:55 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Chna-qaQoKtV for ; Mon, 17 Jan 2022 10:24:55 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.8.0 Received: from smtp2-g21.free.fr (smtp2-g21.free.fr [212.27.42.2]) by smtp3.osuosl.org (Postfix) with ESMTPS id E11906059B for ; Mon, 17 Jan 2022 10:24:54 +0000 (UTC) Received: from ymorin.is-a-geek.org (unknown [IPv6:2a01:cb19:8b51:cb00:3413:1d36:355:a22c]) (Authenticated sender: yann.morin.1998@free.fr) by smtp2-g21.free.fr (Postfix) with ESMTPSA id DCB5E2003DA; Mon, 17 Jan 2022 11:24:50 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=free.fr; s=smtp-20201208; t=1642415093; bh=1MfD1NufGm4QPShlIXMReFBUYde6nd6NF6e18xJa+vI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LqcVLKRk8WJIOpJ2onah6dU3BRoGITh3r3HEgoFMM6jUmy+Zbx1Pj5p3v/AG0Fla8 EgixQUVmCSF5BsMJ7BoLAXS9Gz1KoJ6S8MarQfNRK97MhpqjAbMWuscUFu1IKbCprr ToxQIS2nxlpj4Ab8rXnuOIH4Bfk6pBY4Kd2wdDzjimFJ4SKqCYVI8NaHbUookTwZco IvIknJaY9kcfWtzgqlejTFK3AG3r/oVXFiS8IPcvcWx6RkKJxv3i901uKcG2EADlVE IIBigpXQZvX9M8xmZ63et1C2eYGRiJirb0tFKBi3S/6RPfqY6/duk4H0zdBmT7msBf zwxEhOk8K3RVg== Received: by ymorin.is-a-geek.org (sSMTP sendmail emulation); Mon, 17 Jan 2022 11:24:50 +0100 Date: Mon, 17 Jan 2022 11:24:50 +0100 From: "Yann E. MORIN" To: Danilo Bargen Message-ID: <20220117102450.GC2313964@scaer> References: <20220117105017.28d6aacc@c3po> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220117105017.28d6aacc@c3po> User-Agent: Mutt/1.5.22 (2013-10-16) Subject: Re: [Buildroot] DMARC on this mailing list X-BeenThere: buildroot@buildroot.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion and development of buildroot List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: buildroot@buildroot.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: buildroot-bounces@buildroot.org Sender: "buildroot" Danilo, All, On 2022-01-17 10:50 +0100, Danilo Bargen spake thusly: > I recently enabled report-only DMARC on my e-mail domain. After sending > a few e-mails to this ML yesterday, this resulted in multiple DMARC > would-be rejection e-mails. DMARC has bitten us in the recent past (1.5 year or so...) > DMARC relies on SPF (correct sender IP) *or* DKIM (correct signature). A > nice tool to visualize this is https://www.learndmarc.com/. If either > SPF or DKIM passes, the e-mail should be accepted. > > In the case of mailing lists, the way I understand it, there are two > options: > > - Rewrite the "From:" header so that the e-mail appears to be coming > from the ML itself. Put the original sender e-mail in the "Reply-To" > header instead. If this is not being done, the sender IP (the mailing > list) does not match the sender e-mail domain and SPF fails. Note > that this *might* impact the buildroot ML reputation for some big > mailservers. This is exactly what is going on. You can check for example on the archives: https://lore.kernel.org/buildroot/20220115101415.986123F41E@exit1-us.msgsafe.io/ > - Expect that mail servers with DMARC enabled also have DKIM enabled, > and ensure that the e-mail body is not modified (i.e. turn off the > automatically inserted footer). Put mailing list unsubscribe links > in the headers instead. This way, even though the sender IP does not > match, the signature should still be intact. > > These approaches are described in the following blog post I found > online: https://begriffs.com/posts/2018-09-18-dmarc-mailing-list.html > > I don't know if mailman allows turning off body modifications (i.e. > RFC2369 and RFC2919), but it definitely allows "From"-munging: > https://wiki.list.org/DEV/DMARC Yeah, this is what is being done on this list... Regards, Yann E. MORIN. > I'm still quite new to this mailing list and don't want to put out any > demands, but I wanted to bring up this issue, since it will probably be > more and more of an issue in the future (DMARC adoption is increasing). > > Cheers, > Danilo > _______________________________________________ > buildroot mailing list > buildroot@buildroot.org > https://lists.buildroot.org/mailman/listinfo/buildroot -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 561 099 427 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------' _______________________________________________ buildroot mailing list buildroot@buildroot.org https://lists.buildroot.org/mailman/listinfo/buildroot