From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id C80EA1FF16F for ; Tue, 2 Sep 2025 16:27:45 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 01CB81696F; Tue, 2 Sep 2025 16:28:00 +0200 (CEST) From: Shannon Sterz To: pbs-devel@lists.proxmox.com Date: Tue, 2 Sep 2025 16:27:14 +0200 Message-ID: <20250902142720.371671-1-s.sterz@proxmox.com> X-Mailer: git-send-email 2.47.2 MIME-Version: 1.0 X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1756823232372 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.024 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [lib.rs, canarymail.io] Subject: [pbs-devel] [PATCH proxmox 0/3] improve mail compatability X-BeenThere: pbs-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox Backup Server development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox Backup Server development discussion Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pbs-devel-bounces@lists.proxmox.com Sender: "pbs-devel" this series tries to improve compatability with more mail servers. this is done in three ways: - patch 1: base64 encode filenames of attachments - patch 2: check whether the html or text bodies of an email are ascii only. if they are, we can safely declare 7bit encoding which should be more broadly compatability than the previous 8bit encoding. if the text is not ascii only, encode it as base64 and declare base64 encoding. - patch 3: splits the Content-Disposition header of attached files over two lines, to avoid longer files possibly triggering a line length limit. this should specifically make it possible to support mail servers that don't support SMTPUTF8, as now no part of the header or body should contain plain utf8 characters directly. i tested these patches against the following mail clients: - bluemind - Thunderbird - aerc - canary [1] - iOS Mail app - gmail.com - outlook.com all of them seemed to receive the email and display it properly (note that aerc prefers the TXT part of the mime alternative parts even if the html part should be preferred, due to being a terminal based mua). [1]: https://canarymail.io/ Shannon Sterz (3): sendmail: encode non-ascii filenames to improve compatability sendmail: encode non-ascii bodies as base64 to improve comptability sendmail: break content disposition headers for attachments proxmox-sendmail/src/lib.rs | 193 +++++++++++++++++++++++++++--------- 1 file changed, 147 insertions(+), 46 deletions(-) -- 2.47.2 _______________________________________________ pbs-devel mailing list pbs-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pbs-devel