From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 216F015808B for ; Wed, 13 Apr 2022 13:39:57 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id CE52DE09A5; Wed, 13 Apr 2022 13:39:48 +0000 (UTC) Received: from tncsrv06.tnetconsulting.net (tncsrv06.tnetconsulting.net [IPv6:2600:3c00:e000:1e9::8849]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 9F936E0986 for ; Wed, 13 Apr 2022 13:39:46 +0000 (UTC) Received: from Contact-TNet-Consulting-Abuse-for-assistance by tncsrv06.tnetconsulting.net (8.15.2/8.15.2/Debian-3) with ESMTPSA id 23DDdhMe011440 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO) for ; Wed, 13 Apr 2022 08:39:43 -0500 Subject: Re: [gentoo-user] Fully-Defined-Domain-Name for nullmailer To: gentoo-user@lists.gentoo.org References: <038b7392-bf10-1cf1-b3f2-031901f16199@web.de> <6fa02784-588e-c137-7422-ae81c535453d@web.de> From: Grant Taylor Organization: TNet Consulting Message-ID: Date: Wed, 13 Apr 2022 07:40:18 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply MIME-Version: 1.0 In-Reply-To: <6fa02784-588e-c137-7422-ae81c535453d@web.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Archives-Salt: 3d9b59c8-3cd9-4ee2-b5f5-305106084b86 X-Archives-Hash: a1c08f6fd569edd5e2db5355da6cf016 On 4/13/22 6:31 AM, n952162 wrote: > Unfortunately, I get a 550 from my network provider for all of these: > > 1. me > 2. localdomain > 3. net > 4. web.de > > So, how does thunderbird do it? I don't know what name Thunderbird uses in it's HELO / EHLO command(s). Though it shouldn't matter much which name is used. The important thing should be that the SMTP client, be it Thunderbird or nullmailer or something else, should authenticate to the outbound relay / MSA. The MSA should then use that authentication as a control for what is and is not allowed to be relayed. Nominally, the name used has little effect on the SMTP session. However there is more and more sanity checking being applied for server to server SMTP connections. Mostly the sanity checking is around that a sender isn't obviously lying or trying to get around security checks. These attempts usually take the form of pretending to be the destination or another known / easily identifiable lie. Mail servers that send server to server traffic actually SHOULD use proper names that validate. Clients shouldn't need to adhere to as high a standard. I consider nullmailer to be a client in this case. -- Grant. . . . unix || die