SPF-aware greylisting and filter-greylist

TL;DR: - greylisting is a sound idea - yet it is not really practical today - people tend to disable it or find work-arounds - SPF-aware greylisting makes greylisting usable again Shout outs to my sponsors ! As usual, a huge thanks goes to the people sponsoring me on patreon or github, the work in this post was made possible by my sponsorship. SMTP failures in a nutshell SMTP is a fail-safe protocol which attempts very hard to ensure that messages do not get lost once they are in transit. [Read More]

November 2019 report: OpenSMTPD 6.6.1p1, filter-greylist and tons of portable cleanup

TL;DR: - our CI was improved - a new OpenSMTPD release, 6.6.1p1 took place to deal with portable issues - multiple portability issues were adressed - new table API in the works - filter-rspamd and filter-senderscore were improved - filter-greylist proof-of-concept published - wrote 2 chapters for my book Shout outs to my sponsors ! As usual, a huge thanks goes to the people sponsoring me on patreon or github, the work in this post was made possible by my sponsorship. [Read More]

October 2019 report: OpenSMTPD 6.6.0 release mostly

TL;DR: - yay, surprise emergency hand surgery... - OpenSMTPD 6.6.0 was tagged and released, including portable version - Merged contributions to fix filter-rspamd bug with DKIM - Work resumed on 6.7.0 feature - An OpenSMTPD book is in the works Shout outs to my patrons ! As usual, a huge thanks goes to the people sponsoring me on patreon or github, the work in this post was made possible by my sponsorship. [Read More]

September 2019 report: Jules, OpenSMTPD 6.6.0 upcoming release and related things

TL;DR: - I started writing this post a week ago but got interrupted by a baby, Jules - Spent MANY hours on writing OpenSMTPD-related articles - Enabled continuous integration in the OpenSMTPD portable repository - Managed to get rid of all the blocking issues for OpenSMTPD 6.6.0 release - Added some features and fixed a crash in filter-rspamd Shout outs to my patrons ! As usual, a huge thanks goes to the people sponsoring me on patreon or github, the work in this post was made possible by my sponsorship. [Read More]

Setting up a mail server with OpenSMTPD, Dovecot and Rspamd

TL;DR: - NO TL;DR: this time, I spent hours writing, you should spend minutes reading. - OK... I explain in WAY TOO MUCH details how to setup a mail server EDIT (2019-10-26) OpenSMTPD 6.6.0 was released today, the article was updated to reflect that it applies to the current release and no longer a development version. Wow, that was unexpected In a previous article, I explained why I think the “mail is hard” myth is unfounded and why I think people shouldn’t be discouraged from running their own mail services. [Read More]

You should not run your mail server because mail is hard

TL;DR: - Mail is not hard: people keep repeating that because they read it, not because they tried it - Big Mailer Corps are quite happy with that myth, it keeps their userbase growing - Big Mailer Corps control a large percentage of the e-mail address space which is good for none of us - It's ok that people have their e-mails hosted at Big Mailer Corps as long as there's enough people outside too Disclaimer ** OBVIOUSY, I’M ASSUMING YOU ARE A SYSADMIN, WITH TECH KNOWLEDGE, WHO KNOWS BASIC NETWORKING, HOW TO SETUP SERVICES, HOW TO ADD A DNS RECORD ** [Read More]

August 2019 report: Fion, Plakar and OpenSMTPD

Tl;DR: - small inprovements to the fion window manager - plakar is a backup utility I wrote a long time ago that I will share - tons of opensmtpd stuff, mostly filters and issues handling Shout outs to my patrons ! As has become the habit, this report begins with a big thank you to my patrons, cited by contribution then alphabetical order. This month has been sponsored by: [Read More]

July 2019 report: tons of smtpd work mostly

TL;DR: - not much work outside of OpenSMTPD this week - OpenSMTPD portable builds with OpenSSL 1.1.x again - smtp-out reporting is working correctly on my laptop - wrote two filters that I'm actually using as you read this Shout outs to my patrons ! As will become the tradition hopefully, this report begins with a big thank you to my patrons, cited by contribution then alphabetical order. [Read More]

June 2019 report: fion, bpg and smtpd

TL;DR: - started working on FION, a static tile window manager - revived BPG, a PGP parser - converted OpenSMTPD to libtls - wrote a library to make writing of native C OpenSMTPD filters easy - started writing a filter-rspamd Thanks to my patrons ! First of all, a huge thanks to my first patrons: Bleader Raton Diego Meseguer Mischa Peters Vegar Linge Halaand I have recently switched to a 75% part-time schedule at work so that I can spend a “free” week each month working on my own stuff, mostly opensource, without any kind of pressure: no one knows what I’ll be working on and no one but me gets to decide how I’ll spend this time. [Read More]

May 2019 report

TL;DR: In this post I explain crudely how ca.c works and changes to OpenSMTPD related to ca.c I wrote an ECDSA privsep crypto engine I did some EEG work too This is the first report I will now switch to a monthly report of my tech activities on this blog, and this is the first post in that new format. The focus will be put on interesting topics, not necessarily every single commit and bug fix I do (ie: won’t mention LMTP bug fix here), this depends on the amount of slacking that ocurred during the month and how much I want to cover it up :-) [Read More]