With the announcement of the Let s Encrypt dns-01 challenge support we finally had a way to retrieve certificates for those hosts where http challenges won t work. Also it allows to centralize the signing procedure to avoid the installation and maintenance of letsencrypt clients on all hosts. For an implementation I had the following requirements in my mind:

• Handling of key/csr generation and certificate signing by puppet.
• Private keys don t leave the host they were generated on. If they need to (for HA setups and similar cases), handling needs to be done outside of the letsencrypt puppet module.
• Deployment and cleanup of tokens in our DNS infrastructure should be easy to implement and maintain.

After reading trough the source code of various letsencrypt client implementations I decided to use letsencrypt.sh. Mainly because its dependencies are available pretty much everywhere and adding the necessary hook is as simple as writing some lines of code in your favourite (scripting) language. My second favourite was lego, but I wanted to avoid shipping binaries with puppet, so golang was not an option. It took me some days to find enough spare time to write the necessary puppet code, but finally I managed to release a working module today. It is still not perfect, but the basic tasks are implemented and the whole key/csr/signing chain works pretty well. And if your hook can handle it, http-01 challenges are possible, too! Please give the module a try and send patches if you would like to help to improve it!

• Puppet Forge: https://forge.puppetlabs.com/bzed/letsencrypt
• Github: https://github.com/bzed/bzed-letsencrypt
• Issue tracker: https://github.com/bzed/bzed-letsencrypt/issues

debtags.debian.org cleaned up Since the Debtags consolidation announcement there are some more news: No more anonymous submissions

• I have disabled anonymous tagging. Anyone is still able to tag via Debian Single Sign-On. SSO-enabling the site was as simple as this.
• Tags need no review anymore to be sent to ftp-master. I have removed all the distinction in the code between reviwed and unreviewed tags, and all the code for the tag review interface.
• The site now has an audit log for each user, that any person logged in via SSO can access via the "history" link in the top right of the tag editor page.

Official recognition as Debian Contributors

• Tag contributions are sent to contributors.debian.org. There is no historical data for them because all submissions until now have been anonymous, but from now on if you tag packages you are finally recognised as a Debian Contributor!

Mailing lists closed

• I closed the debtags-devel and debtags-commits mailing lists; the archives are still online.
• I have updated the workflow for suggesting new tags in the FAQ to "submit a bug to debtags and Cc debian-devel"

We can just use debian-devel instead of debtags-devel. Autotagging of trivial packages

• I have introduced the concept of "trivial" packages to currently be any package in the libs, oldlibs and debug sections. They are tagged automatically by the site maintenance and are excluded from the site todo lists and tag editor. We do not need to bother about trivial packages anymore, all 13239 of them.

Miscellaneous other changes

• I have moved the debtags vocabulary from subversion to git
• I have renamed the tag used to mark packages not yet reviewed by humans from special::not-yet-tagged to special::unreviewed
• At the end of every nightly maintenance, some statistics are saved into a database table. I have collected 10 years of historical data by crunching big tarballs of site backups, and fed them to the historical stats table.
• The workflow for getting tags from the site to ftp-master is now far, far simpler. It is almost simple enough that I should manage to explain it without needing to dig through code to see what it is actually doing.

Yesterday, I pushed out version 2.11.18 of the Geode X.Org driver. This is the driver used by the OLPC XO-1 and by a plethora of low-power desktops, micro notebooks and thin clients. This release mostly includes maintenance fixes of all sorts. Of noticeable interest is a fix for the long-standing issue that switching between X and a VT would result in a blank screen (this should probably be cherry-picked for distributions running earlier releases of this driver). Many thanks to Connor Behan for the fix!
Unfortunately, this driver still doesn't work with GNOME. On my testing host, launching GDM produces a blank screen. 'ps' and other tools show that GDM is running but there's no screen content; the screen remains pitch black. This issue doesn't happen with other display managers e.g. LightDM. Bug reports have been filed, additional information was provided, but the issue still hasn't been resolved.
Additionally, X server flat out crashes on Geode hosts running Linux kernels 4.2 or newer. 'xkbcomp' repeatedly fails to launch and X exits with a fatal error. Bug reports have been filed, but not reacted to. However, interestingly enough, X launches fine if my testing host is booted with earliers kernels, which might suggest what the actual cause of this particular bug might be:
Since kernel 4.2 entered Debian, the base level i386 kernel on Debian is now compiled for i686 (without PAE). Until now, the base level was i586. This essentially makes it pointless to build the Geode driver with GX2 support. It also means that older GX1 hardware won't be able to run Debian either, starting with the next stable release.

At LCA I attended a talk about Unikernels. Here are the reasons why I think that they are a bad idea: Single Address Space According to the Unikernel Wikipedia page [1] a significant criteria for a Unikernel system is that it has a single address space. This gives performance benefits as there is no need to change CPU memory mappings when making system calls. But the disadvantage is that any code in the application/kernel can access any other code directly. In a typical modern OS (Linux, BSD, Windows, etc) every application has a separate address space and there are separate memory regions for code and data. While an application can request the ability to modify it s own executable code in some situations (if the OS is configured to allow that) it won t happen by default. In MS-DOS and in a Unikernel system all code has read/write/execute access to all memory. MS-DOS was the least reliable OS that I ever used. It was unreliable because it performed tasks that were more complex than CP/M but had no memory protection so any bug in any code was likely to cause a system crash. The crash could be delayed by some time (EG corrupting data structures that are only rarely accessed) which would make it very difficult to fix. It would be possible to have a Unikernel system with non-modifyable executable areas and non-executable data areas and it is conceivable that a virtual machine system like Xen could enforce that. But that still wouldn t solve the problem of all code being able to write to all data. On a Linux system when an application writes to the wrong address there is a reasonable probability that it will not have write access and you will immediately get a SEGV which is logged and informs the sysadmin of the address of the crash. When Linux applications have bugs that are difficult to diagnose (EG buffer overruns that happen in production and can t be reproduced in a test environment) there are a variety of ways of debugging them. Tools such as Valgrind can analyse memory access and tell the developers which code had a bug and what the bug does. It s theoretically possible to link something like Valgrind into a Unikernel, but the lack of multiple processes would make it difficult to manage. Debugging A full Unix environment has a rich array of debugging tools, strace, ltrace, gdb, valgrind and more. If there are performance problems then tools like sysstat, sar, iostat, top, iotop, and more. I don t know which of those tools I might need to debug problems at some future time. I don t think that any Internet facing service can be expected to be reliable enough that it will never need any sort of debugging. Service Complexity It s very rare for a server to have only a single process performing the essential tasks. It s not uncommon to have a web server running CGI-BIN scripts or calling shell scripts from PHP code as part of the essential service. Also many Unix daemons are not written to run as a single process, at least threading is required and many daemons require multiple processes. It s also very common for the design of a daemon to rely on a cron job to clean up temporary files etc. It is possible to build the functionality of cron into a Unikernel, but that means more potential bugs and more time spent not actually developing the core application. One could argue that there are design benefits to writing simple servers that don t require multiple programs. But most programmers aren t used to doing that and in many cases it would result in a less efficient result. One can also argue that a Finite State Machine design is the best way to deal with many problems that are usually solved by multi-threading or multiple processes. But most programmers are better at writing threaded code so forcing programmers to use a FSM design doesn t seem like a good idea for security. Management The typical server programs rely on cron jobs to rotate log files and monitoring software to inspect the state of the system for the purposes of graphing performance and flagging potential problems. It would be possible to compile the functionality of something like the Nagios NRPE into a Unikernel if you want to have your monitoring code running in the kernel. I ve seen something very similar implemented in the past, the CA Unicenter monitoring system on Solaris used to have a kernel module for monitoring (I don t know why). My experience was that Unicenter caused many kernel panics and more downtime than all other problems combined. It would not be difficult to write better code than the typical CA employee, but writing code that is good enough to have a monitoring system running in the kernel on a single-threaded system is asking a lot. One of the claimed benefits of a Unikernel was that it s supposedly risky to allow ssh access. The recent ssh security issue was an attack against the ssh client if it connected to a hostile server. If you had a ssh server only accepting connections from management workstations (a reasonably common configuration for running servers) and only allowed the ssh clients to connect to servers related to work (an uncommon configuration that s not difficult to implement) then there wouldn t be any problems in this regard. I think that I m a good programmer, but I don t think that I can write server code that s likely to be more secure than sshd. On Designing It Yourself One thing that everyone who has any experience in security has witnessed is that people who design their own encryption inevitably do it badly. The people who are experts in cryptology don t design their own custom algorithm because they know that encryption algorithms need significant review before they can be trusted. The people who know how to do it well know that they can t do it well on their own. The people who know little just go ahead and do it. I think that the same thing applies to operating systems. I ve contributed a few patches to the Linux kernel and spent a lot of time working on SE Linux (including maintaining out of tree kernel patches) and know how hard it is to do it properly. Even though I m a good programmer I know better than to think I could just build my own kernel and expect it to be secure. I think that the Unikernel people haven t learned this.

• [1] https://en.wikipedia.org/wiki/Unikernel

After finishing the Talos Principle I immediately started to play the extension Road to Gehenna, but was derailed near completion by the incredible Portal Stories: Mel. Now that I finally managed to escape from the test chambers my attention returned to the Road to Gehenna. As with the pair Portal 2 and Portal Stories: Mel, the challenges are going up considerably from the original Talos Principle to the Road to Gehenna. Checking the hours of game play it took me about 24h through all the riddles in Road to Gehenna, but I have to admit, I had some riddles where I needed to cheat. The Road to Gehenna does not bring much new game play elements, but loads of new riddles. And the best of all, playable on Linux! And as with the original game, the graphics are really well done, while still be playable on my Vaio Pro laptop with Intel integrated graphic card a plus that is rare in the world of computer games where everyone is expected to have a high-end nVidia or Radeon card. Ok, there is not much action going on where quick graphic computations are necessary, still the impression of the game is great.
The riddles contain the well known elements (connectors, boxes, jammer, etc), but the settings are often spectacular, sometimes very small and narrow, just a few moves if done in the right order, sometimes like wide open fields with lots of space to explore. Transportation between various islands suspended in the air is with vents, giving you a lot of nice flight time!
If one searches a lot, or uses a bit of cheating, one can find good old friends from the Portal series, burried in the sand in one of the world. This is not the only easter egg hidden in the game, there are actually a lot, some of which I have not seen but only read about afterwards. Guess I need to replay the whole game.
Coming back to the riddles, I really believe that the makers have been ingenious in using the few items at hand to create challenging and surprising riddles. As it is so often, many of the riddles look completely impossible at first glance, and often even after staring at them for tens and tens of minutes. Until (and if) one has the the a-ha effect and understands the trick. This often still needs a lot of handwork and trial-error rounds, but all in all the game is well balanced. What is a bit a pain similar to the original game are collecting the stars to reach the hidden world and free the admin. There the developers overdid it in my opinion, with some rather absurd and complicated stars.
The end of the game, ascension of the messengers, is rather unspectacular. A short discussion on who remains and then a big closing scene with the messenger being beamed up a la Starship Enterprise, and a closing black screen. But well, the fun was with the riddles.
All in all an extension that is well worth the investment if one enjoyed the original Talos, and is looking for rather challenging riddles. Now that I have finished all the Portal and Talos titles, I am hard thinking of what is next looking into Braid Enjoy!

As I've already mentioned in separate blog post we mostly had some security issues fun in past weeks, but besides that some other work has been done as well. I've still focused on code cleanups and identified several pieces of code which are no longer needed (given our required PHP version). Another issue related to security updates was to set testing of 4.0 branch using PHP 5.2 as this is what we've messed up in the security release (what is quite bad as this is only branch supporting PHP 5.2). In addition to this, I've updated phpMyAdmin packages in both Debian and Ubuntu PPA. All handled issues:

• #11902 Fix issue 11834
• #11900 Fix #11896 Remove hard dependency on phpseclib
• #11899 Fixes for #11892 and #11896 for 4.5 branch
• #11895 4.5.4 not in STABLE branch.
• #11894 Fix #11892 Error with PMA 4.4.15.3
• #11893 Fix #11891 Error with PMA 4.0.10.13 with PHP 5.2
• #11889 Update documents with Isaac as the new release manager
• #11888 Update release verification docs for Isaac
• #11886 CI failure notifications to mailing list
• #11883 HTTPS Redirect Loop when using ForceSSL on CentOS7 with Apache
• #11882 Add note about passing HTTP auth headers when running as FastCGI

Filed under: Debian English phpMyAdmin 0 comments

Compatibility/interoperability is a good thing. It s generally good for systems on the Internet to be capable of communicating with as many systems as possible. Unfortunately it s not always possible as new features sometimes break compatibility with older systems. Sometimes you have systems that are simply broken, for example all the systems with firewalls that block ICMP so that connections hang when the packet size gets too big. Sometimes to take advantage of new features you have to potentially trigger issues with broken systems. I recently added support for IPv6 to the Linux Users of Victoria server. I think that adding IPv6 support is a good thing due to the lack of IPv4 addresses even though there are hardly any systems that are unable to access IPv4. One of the benefits of this for club members is that it s a platform they can use for testing IPv6 connectivity with a friendly sysadmin to help them diagnose problems. I recently notified a member by email that the callback that their mail server used as an anti-spam measure didn t work with IPv6 and was causing mail to be incorrectly rejected. It s obviously a benefit for that user to have the problem with a small local server than with something like Gmail. In spite of the fact that at least one user had problems and others potentially had problems I think it s clear that adding IPv6 support was the correct thing to do. SSL Issues Ben wrote a good post about SSL security [1] which links to a test suite for SSL servers [2]. I tested the LUV web site and got A-. This blog post describes how to setup PFS (Perfect Forward Secrecy) [3], after following it s advice I got a score of B! From the comments on this blog post about RC4 etc [4] it seems that the only way to have PFS and not be vulnerable to other issues is to require TLS 1.2. So the issue is what systems can t use TLS 1.2. TLS 1.2 Support in Browsers This Wikipedia page has information on SSL support in various web browsers [5]. If we require TLS 1.2 we break support of the following browsers: The default Android browser before Android 5.0. Admittedly that browser always sucked badly and probably has lots of other security issues and there are alternate browsers. One problem is that many people who install better browsers on Android devices (such as Chrome) will still have their OS configured to use the default browser for URLs opened by other programs (EG email and IM). Chrome versions before 30 didn t support it. But version 30 was released in 2013 and Google does a good job of forcing upgrades. A Debian/Wheezy system I run is now displaying warnings from the google-chrome package saying that Wheezy is too old and won t be supported for long! Firefox before version 27 didn t support it (the Wikipedia page is unclear about versions 27-31). 27 was released in 2014. Debian/Wheezy has version 38, Debian/Squeeze has Iceweasel 3.5.16 which doesn t support it. I think it is reasonable to assume that anyone who s still using Squeeze is using it for a server given it s age and the fact that LTS is based on packages related to being a server. IE version 11 supports it and runs on Windows 7+ (all supported versions of Windows). IE 10 doesn t support it and runs on Windows 7 and Windows 8. Are the free upgrades from Windows 7 to Windows 10 going to solve this problem? Do we want to support Windows 7 systems that haven t been upgraded to the latest IE? Do we want to support versions of Windows that MS doesn t support? Windows mobile doesn t have enough users to care about. Opera supports it from version 17. This is noteworthy because Opera used to be good for devices running older versions of Android that aren t supported by Chrome. Safari supported it from iOS version 5, I think that s a solved problem given the way Apple makes it easy for users to upgrade and strongly encourages them to do so. Log Analysis For many servers the correct thing to do before even discussing the issue is to look at the logs and see how many people use the various browsers. One problem with that approach on a Linux community site is that the people who visit the site most often will be more likely to use recent Linux browsers but older Windows systems will be more common among people visiting the site for the first time. Another issue is that there isn t an easy way of determining who is a serious user, unlike for example a shopping site where one could search for log entries about sales. I did a quick search of the Apache logs and found many entries about browsers that purport to be IE6 and other versions of IE before 11. But most of those log entries were from other countries, while some people from other countries visit the club web site it s not very common. Most access from outside Australia would be from bots, and the bots probably fake their user agent. Should We Do It? Is breaking support for Debian/Squeeze, the built in Android browser on Android <5.0, and Windows 7 and 8 systems that haven t upgraded IE as a web browsing platform a reasonable trade-off for implementing the best SSL security features? For the LUV server as a stand-alone issue the answer would be no as the only really secret data there is accessed via ssh. For a general web infrastructure issue it seems that the answer might be yes. I think that it benefits the community to allow members to test against server configurations that will become more popular in the future. After implementing changes in the server I can advise club members (and general community members) about how to configure their servers for similar results. Does this outweigh the problems caused by some potential users of ancient systems? I m blogging about this because I think that the issues of configuration of community servers have a greater scope than my local LUG. I welcome comments about these issues, as well as about the SSL compatibility issues.

• [1] https://www.decadent.org.uk/ben/blog/securing-wwwdecadentorguk.html
• [2] https://www.ssllabs.com/ssltest/
• [3] https://blog.qualys.com/ssllabs/2013/08/05/configuring-apache-nginx-and-openssl-for-forward-secrecy
• [4] https://blog.qualys.com/ssllabs/2013/03/19/rc4-in-tls-is-broken-now-what
• [5] https://en.wikipedia.org/wiki/Template:TLS/SSL_support_history_of_web_browsers

What happened in the reproducible builds effort between January 24th and January 30th:

Media coverage Holger Levsen was interviewed by the FOSDEM team to introduce his talk on Sunday 31st.

Toolchain fixes Jonas Smedegaard uploaded d-shlibs/0.63 which makes the order of dependencies generated by d-devlibdeps stable accross locales. Original patch by Reiner Herrmann.

Packages fixed The following 53 packages have become reproducible due to changes in their build dependencies: appstream-glib, aptitude, arbtt, btrfs-tools, cinnamon-settings-daemon, cppcheck, debian-security-support, easytag, gitit, gnash, gnome-control-center, gnome-keyring, gnome-shell, gnome-software, graphite2, gtk+2.0, gupnp, gvfs, gyp, hgview, htmlcxx, i3status, imms, irker, jmapviewer, katarakt, kmod, lastpass-cli, libaccounts-glib, libam7xxx, libldm, libopenobex, libsecret, linthesia, mate-session-manager, mpris-remote, network-manager, paprefs, php-opencloud, pisa, pyacidobasic, python-pymzml, python-pyscss, qtquick1-opensource-src, rdkit, ruby-rails-html-sanitizer, shellex, slony1-2, spacezero, spamprobe, sugar-toolkit-gtk3, tachyon, tgt. The following packages became reproducible after getting fixed:

• angband-doc/3.0.3.6 by Manoj Srivastava, obsolete patch by Chris Lamb.
• atdgen/1.7.2-1 by St phane Glondu.
• bibtool/2.63+ds-1 by Jerome Benoit.
• cglib/3.2.0-1 by Emmanuel Bourg.
• cmst/2016.01.28-1 by Alf Gaida.
• coreutils/8.25-1 uploded by Michael Stone, fixed upstream.
• doc-base/0.10.7 uploaded by Robert Luberda, original patch by Dhole.
• fpc/3.0.0+dfsg-1 uploaded by Paul Gevers.
• libaqbanking/5.6.4beta-1 by Micha Lenk.
• libgcrypt20/1.6.4-5 uploaded by Andreas Metzler, original patch by Lunar.
• libgwenhywfar/4.15.2beta-1 by Micha Lenk.
• libxdmcp/1:1.1.2-1.1 by Helmut Grohne (report).
• lpe/1.2.8-2 by Adam Majer, obsolete patches (#778197, #793697 by Chris Lamb and akira.
• mariadb-10.0/10.0.23-2 by Otto Kek l inen.
• mixxx/2.0.0~dfsg-1 by Sebastian Ramacher.
• pd-lua/0.7.3-1 by IOhannes m zm lnig.
• pd-zexy/2.2.6-2 by IOhannes m zm lnig.
• polymake/3.0-1 uploaded by David Bremner, fixed upstream.
• prometheus/0.16.2+ds-1 by Mart n Ferrari.
• screengrab/1.95+20160128-1 uploaded by Alf Gaida (report).
• spykeviewer/0.4.4-1 by Robert Pr pper, original patch by Reiner Herrmann.
• testdisk/7.0-1 uploaded by Roland Stigge, upstream patch reported by Mattia Rizzolo.
• xorg/1:7.7+13 uploaded by Timo Aaltonen, original patch by Dhole, merged by Andreas Boll.

Some uploads fixed some reproducibility issues, but not all of them:

• gnubg/1.05.000-4 by Russ Allbery.
• grcompiler/4.2-6 by Hideki Yamane.
• sdlgfx/2.0.25-5 fix by Felix Geyer, uploaded by Gianfranco Costamagna.

Patches submitted which have not made their way to the archive yet:

• #812876 on glib2.0 by Lunar: ensure that functions are sorted using the C locale when giotypefuncs.c is generated.

diffoscope development diffoscope 48 was released on January 26th. It fixes several issues introduced by the retrieval of extra symbols from Debian debug packages. It also restores compatibility with older versions of binutils which does not support readelf --decompress.

strip-nondeterminism development strip-nondeterminism 0.015-1 was uploaded on January 27th. It fixes handling of signed JAR files which are now going to be ignored to keep the signatures intact.

Package reviews 54 reviews have been removed, 36 added and 17 updated in the previous week. 30 new FTBFS bugs have been submitted by Chris Lamb, Michael Tautschnig, Mattia Rizzolo, Tobias Frost.

Misc. Alexander Couzens and Bryan Newbold have been busy fixing more issues in OpenWrt. Version 1.6.3 of FreeBSD's package manager pkg(8) now supports SOURCE_DATE_EPOCH. Ross Karchner did a lightning talk about reproducible builds at his work place and shared the slides.

My monthly report covers a large part of what I have been doing in the free software world. I write it for my donators (thanks to them!) but also for the wider Debian community because it can give ideas to newcomers and it s one of the best ways to find volunteers to work with me on projects that matter to me. Debian LTS I did not ask for any paid hours this month and won t be requesting paid hours for the next 5 months as I have a big project to handle with a deadline in June. That said I still did a few LTS related tasks:

• I uploaded a new version of debian-security-support (2016.01.07) to officialize that virtualbox-ose is no longer supported in Squeeze and that redmine was not really supportable ever since we dropped support for rails.
• Made a summary of the discussion about what to support in wheezy and started a new round of discussions with some open questions. I invited contributors to try to pickup one topic, study it and bring the discussion to some conclusion.
• I wrote a blog post to recruit new paid contributors. Brian May, Markus Koschany and Damyan Ivanov candidated and will do their first paid hours over February.

Distro Tracker Due to many nights spent on playing Splatoon (I m at level 33, rank B+, anyone else playing it?), I did not do much work on Distro Tracker. After having received the bug report #809211, I investigated the reasons why SQLite was no longer working satisfactorily in Django 1.9 and I opened the upstream ticket 26063 and I had a long discussion with two upstream developers to find out the best fix. The next point release (1.9.2) will fix that annoying regression. I also merged a couple of contributions (two patches from Christophe Siraut, one adding descriptions to keywords, cf #754413, one making it more obvious that chevrons in action items are actionable to show more data, a patch from Balasankar C in #810226 fixing a bad URL in an action item). I fixed a small bug in the unsubscribe command of the mail bot, it was not properly recognizing source packages. I updated the task notifying of new upstream versions to use the data generated by UDD (instead of the data generated by Christoph Berg s mole-based implementation which was suffering from a few bugs). Debian Packaging Testing experimental sbuild. While following the work of Johannes Schauer on sbuild, I installed the version from experimental to support his work and give him some feedback. In the process I uncovered #810248. Python sponsorship. I reviewed and uploaded many packages for Daniel Stender who keeps doing great work maintaining prospector and all its recursive dependencies: pylint-common, python-requirements-detector, sphinx-argparse, pylint-django, prospector. He also prepared an upload of python-bcrypt which I requested last month for Django. Django packaging. I uploaded Django 1.8.8 to jessie-backports.
My stable updates for Django 1.7.11 was not handled before the release of Debian 8.3 even though it was filed more than 1.5 months before. Misc stuff. My stable update for debian-handbook has been accepted fairly shortly after my last monthly report (thank you Adam!) so I uploaded the package once acked by a release manager. I also sponsor a backports upload of zim prepared by Joerg Desch. Kali related work Kernel work. The switch to Linux 4.3 in Kali resulted in a few bug reports that I investigated with the help of #debian-kernel and where I reported my findings back so that the Debian kernel could also benefit from the fixes I uploaded to Kali: first we included a patch for a regression in the vmwgfx video driver used by VMWare virtual machines (which broke the gdm login screen), then we fixed the input-modules udeb to fix support of some Logitech keyboards in debian-installer (see #796096). Misc work. I made a non-maintainer upload of python-maxminddb to fix #805689 which had been removed from stretch and that we needed in Kali. I also had to NMU libmaxminddb since it was no longer available on armel and we actually support armel in Kali. During that NMU, it occurred to me that dh-exec could offer a feature of optional install , that is installing a file that exists but not failing if it doesn t exist. I filed this as #811064 and it stirred up quite some debate. Thanks See you next month for a new summary of my activities.

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Review: Oathblood, by Mercedes Lackey

Series:	Vows and Honor #3
Publisher:	DAW
Copyright:	April 1998
ISBN:	0-88677-773-9
Format:	Mass market
Pages:	394

I have this story collection listed as the third book in the Vows and Honor series, but as mentioned in the review of The Oathbound, it's more complicated than that. This book has the first Tarma and Kethry story, which is not found in The Oathbound, and two of the better stories from that volume. This is probably the place to start for the series; you're not missing that much from the rest of that book. However, the last three stories ("Wings of Fire," "Spring Plowing at Forst Reach," and "Oathblood") have significant spoilers for Oathbreakers. Therefore, if you care about both avoiding spoilers and reading this series, my recommended reading order is to ignore The Oathbound entirely, read Oathblood up to but not including "Wings of Fire," read Oathbreakers, and then come back here for the last two stories. "Sword-sworn": This is the very first Tarma and Kethry story and hence where this series actually begins. As Lackey notes in her introduction, it's a pretty stock "rape and revenge" story, which is not something I particularly enjoy. Marion Zimmer Bradley liked it well enough to accept it anyway, and I can sort of see why: the dynamic between the two characters sparkles in a few places, and the Shin'a'in world-building isn't bad. The plot, though, is very predictable and not very notable. There isn't much here that you'd be surprised by if you'd read references to these events in later stories. And there's no explanation of a few things one might be curious about, such as where Need came from. (6) "Turnabout": This is one of the two stories also found in The Oathbound. Merchants are plagued by bandits who manage to see through ruses and always catch their guards by surprise (with a particularly nasty bit of rape and murder in one case Tarma and Kethry stories have quite a lot of that). That's enough to get the duo to take the job of luring out the bandits and dealing with them, using a nice bit of magical disguise. This story is also a song on one of the Vows and Honor albums from Firebird (which I also have). It was one of my favorites of Lackey's songs, so I want to like the story (and used to like it a great deal). Unfortunately, the very nasty bit of revenge that the supposed heroes take at the end of the story completely destroyed my enjoyment of it on re-reading. It's essentially a glorification of prison rape, which is a trope that I no longer have any patience for. (4) "The Making of a Legend": In order to explain the differences between the song based on "Turnabout" and the actual story, Lackey invented a bard, Leslac, who loves writing songs about Tarma and Kethry and regularly gets the details wrong, mostly by advertising them as moral crusaders for women instead of mercenaries who want to get paid, much to their deep annoyance. This is his debut in an actual story, featuring an incident that's delightfully contrary to Leslac's expectations. It's a slight story, but I thought it was fun. (6) "Keys": Another story from The Oathbound, this is a locked-room mystery with a bit of magical sleuthing. Kethry attempts to prove that a woman did not murder her husband while Tarma serves as her champion in a (rather broken) version of trial by combat. I think the version here is better than the edited version in The Oathbound, and it's a fairly enjoyable bit of sleuthing. (7) "A Woman's Weapon": I would call this the typical Tarma and Kethry story (except that, for a change, it's missing the rape): they stumble across some sort of serious injustice and put things to right with some hard thinking and a bit of poetic justice. In this case, it's a tannery that's poisoning the land, and a master tanner who can't put a stop to his rival. Competent although not particularly memorable. (6) "The Talisman": A rather depressing little story about a mage who wants shortcuts and a magic talisman that isn't what it appears to be. Not one of my favorites, in part because it has some common Tarma and Kethry problems: unnecessary death, a feeling that the world is very dangerous and that mistakes are fatal, and narrative presentation of the people who die from their stupidity as deserving it. I couldn't shake the feeling that there was probably some better way of resolving this if people had just communicated a bit better. (5) "A Tale of Heroes": Back to the rape, unfortunately, plus a bit of very convenient match-making that I found extremely dubious. For all that Lackey's introduction paints this as a story of empowering people to follow their own paths, the chambermaid of this story didn't seem to have many more choices in her life after meeting Tarma and Kethry than before, even if her physical situation was better. I did like the touch of Tarma and Kethry not being the heroes and victors in the significant magical problem they stumble across, though, and it's a warm-hearted story if you ignore the effects of trauma as much as the story ignores them. (6) "Friendly Fire": An amusing short story about the power of bad luck and Murphy's Law. It hit one of my pet peeves at one point, where Lackey tries to distort the words of someone with a cold and just makes the dialogue irritating to read, but otherwise a lot of fun. (7) "Wings of Fire": I love the Hawkbrothers, so it's always fun when they show up. The villain of this piece is way over the top and leaves much to be desired, but the guest-starring Hawkbrother mostly makes up for it. Once again, Tarma and Kethry get out of a tight spot by thinking harder instead of by having more power, although the villain makes that rather easy via overconfidence. Once again, though, the poetic justice that Lackey's protagonists enjoy leaves a bad taste in my mouth, although it's not quite as bad here as some other stories. (6) "Spring Planting at Forst Reach": On one level, this is a rather prosaic story about training horses (based on Lackey's experience and reading, so a bit better than typical fantasy horse stories). But it's set at Forst Reach, Vanyel's home, some years after Vanyel. I like those people and their gruff approach to life, and it meshes well with Tarma and Kethry's approach. If you enjoy the two showing off their skills and wowing people with new ideas, you'll have fun with this. (7) "Oathblood": As you might guess from the matching title, this novella is the heart of the book and about a quarter of its length. We get to see Kethry's kids, see more of their life in their second (post-Oathbreakers) career, and then get a rather good adventure story of resourceful and thoughtful youngsters, with a nice touch of immature but deeply-meant loyalty. I didn't enjoy it as much as I would have without one of the tactics the kids use to get out of trouble, but my dislike for reading about other people's bowel troubles is partly a personal quirk. This is a pretty typical Lackey story of resourcefulness and courage; if you like this series in general, you'll probably enjoy this one. (7) Rating: 7 out of 10

Over these past few months, I've been going through my personal belongings to reduce them to the bare essentials more-or-less following the rule "If I cannot remember that I had it, I probably don't need it" with an explicit goal to make it easier for me to relocate in the near future.Part of that iterative process has involved selling surplus items via Facebook groups. While I initially rejoiced at the invention of the new Selling Something feature, the more I use it, the more I end up cursing at the lack of thought that went into designing that feature:For instance, in the feature's most recent implementation, it has become possible to post the same ad in several groups. Great idea, right? Actually, no. What this option does is post individual copies of that exact same ad in each group. Managed to sell a particular item? You'll have to sort through each and every duplicate post in each group to mark the item as sold. Need to edit the ad to lower the price or add requested information about the item? Same thing: go through each individual copy of the ad in each group. Seriously, Facebook? Who the fuck designed that senseless implementation?!Here's a better implementation: centrally manage all items via the user's account preferences, and let the user tick checkboxes besides each item to decide which groups will see that particular item. Ditto whenever editing the ad's content or marking an item as sold; do everything via the user's account preferences. Rather than making the content group-centric, make it user-centric.You're welcome.

At Debconf15 I gave a talk on topic of having backups be a default service on Debian machines. In that talk, I proposed that we create infrastructure to be included in a default Debian install to manage backups. I still think this is a good idea, but over the past several months, I've had nearly no time at all to actually do this. I'm afraid I have to say now that I won't be able to work on this in time for the stretch release. I would be very happy for others to do that, however. The Debian wiki page https://wiki.debian.org/Backup acts as a central point of information for this. If you're interested in working on this, you can just do it.

Here is my monthly update covering a large part of what I have been doing in the free software world (previously):

• Changed Django's project/app templates to use a py-tpl suffix to workaround the 1.9 release series shipping invalid .py files that are used as templates. (#5735)
• Pushed a number of updates to my Strava Enhancement Suite Chrome extension:
  • Added the ability to sort starred segments first. (#42)
  • Added an option to display hidden segments by default. (#34)
  • Also hide "Yearly Goals" as part of hiding upcoming data. (#41)
  • Removed more "premium" badges. (#43)
  • Fixed an issue where removing feed entries didn't correctly cleanup subsequently-empty date headers. (commit)
• Released a work-in-progress django.contrib.staticfiles library to recursively transparently concatenate Javascript and CSS files using "Debian-style" .d directories. I had previously been doing this manually via the various release processes and bespoke views during development as the idea pre-dated the existence of the staticfiles framework. (Repo)
• Updated travis.debian.net, a hosted script to easily test and build Debian packages on Travis CI, to support the wheezy distribution and to improve error-handling in general. (Repo)
• Ensured that try.diffoscope.org, a hosted version of the diffoscope in-depth and content aware diff utility, periodically cleans up containers.
• Moved my personal music library to use dh-virtualenv and to deploy to its own server via Ansible. I also updated the codebase to the latest version of Django at the same time, taking advantage of a large number of new features and recommendations.
• Fixed a strange issue with empty IMAP messages in my tickle-me-email GTD email toolbox.
• It was also a month of significant bug reports and feature requests being sent to my private email.

---

So many options, so little time. Many years ago I handled all my network connections via /etc/network/interfaces. Then, I was in desperate need of a Internet connection and all I had was a borrowed USB cell phone modem. My friends running NetworkManager just plugged the stick in and were online. I was left with the task of figuring out how to manually configure this piece of hardware without being online. I ended up borrowing my friend's computer. Then, when I got home, I installed NetworkManager. Once I had NetworkManager installed, I decided it was easier to find, connect to and manage passwords of wireless networks using a graphical tool rather than digging through the copious output of commands run from my terminal and trying to keep track of the passwords. So long wireless. Then I had to help a colleague get on our Virtual Private Network. Wow. There's a NetworkManager GUI for that too. If I'm going to support my colleauge with this tool... I guess I should use it as well. I also managed to write a dispatcher script in /etc/NetworkManager/dispatcher.d that calls su -c "/usr/bin/smbnetfs /media/smbnetfs" -l jamie when it receives and action of "vpn-up" and umount /media/smbnetfs 2>/dev/null on "vpn-down." Now I can mount the samba share by simply connecting to the VPN via NetworkManager. My cable connections are almost always configured using DHCP. Almost everything else is in NetworkManager, why not move enp1s0f2 as well? What's left? My final piece is my bridge. I still run and manage my own KVM guests and I have a bridge to handle that traffic. I first decided to move this functionality to systemd.network because systemd can not only handle the bridge, but can also handle IP Forwarding, DHCP service, and best of all, IP Masquerading. Well, almost... not IP Masquerading after all, at least not yet. Without IP masquerading, I figured I'd go with NetworkManager. Having all networking in the same place gives me an illusion of control at best and at worst makes it easier to debug. So, I setup a crufty script in /etc/NetworkManager/dispatcher.d that configures masquerading via iptables everytime either my wireless or wired network goes up or down, which I'm not crazy about. Maybe when #787480 is fixed I'll got back to systemd. I also edited /etc/sysctl.conf to enable #net.ipv4.ip_forward=1. Then I changed it back and added my own file in /etc/sysctl.d to do the same thing. Then I deleted that file and added sysctl net.ipv4.ip_forward=1 and sysctl net.ipv4.ip_forward=0 to my crufty dispatcher script. I decided to do without DHCP - I can manually configure the few KVM instances that I run. Now /etc/network/interfaces is so lonely.

Over the last few days I've been at the GNOME Developer Experience hackfest in Brussels, looking into xdg-app and how best to use it in Debian and Debian derivatives. xdg-app is basically a way to run "non-core" software on Linux distributions, analogous to apps on Android and iOS. It doesn't replace distributions like Debian or packaging systems, but it adds a layer above them. It's mostly aimed towards third-party apps obtained from somewhere that isn't your distribution vendor, aiming to address a few long-standing problems in that space:

• There's no single ABI that can be called "a standard Linux system" in the same way there would be for Windows or OS X or Android or whatever, apart from LSB which is rather limited. Testing that a third-party app "works on Linux", or even "works on stable Linux releases from 2015", involves a combinatorial explosion of different distributions, desktop environments and local configurations. Steam uses the Steam Runtime, a chroot environment closely resembling Ubuntu 12.04 LTS; other vendors tend to test on a vaguely recent Ubuntu LTS and leave it at that.
• There's no widely-supported mechanism for installing third-party applications as an ordinary user. gog.com used to distribute Ubuntu- and Debian-compatible .deb files, but installing a .deb involves running arbitrary vendor-supplied scripts as root, which should worry anyone who wants any sort of privilege-separation. (They have now switched to executable self-extracting installers, which involve running arbitrary vendor-supplied scripts as an ordinary user... better, but not perfect.)
• Relatedly, the third-party application itself runs with the user's full privileges: a malicious or security-buggy third-party application can do more or less anything, unless you either switch to a different uid to run third-party apps, or use a carefully-written, app-specific AppArmor profile or equivalent.

To address the first point, each application uses a specified "runtime", which is available as /usr inside its sandbox. This can be used to run application bundles with multiple, potentially incompatible sets of dependencies within the same desktop environment. A runtime can be updated within its branch - for instance, if an application uses the "GNOME 3.18" runtime (consisting of a basic Linux system, the GNOME 3.18 libraries, other related libraries like Mesa, and their recursive dependencies like libjpeg), it can expect to see minor-version updates from GNOME 3.18.x (including any security updates that might be necessary for the bundled libraries), but not a jump to GNOME 3.20. To address the second issue, the plan is for application bundles to be available as a single file, containing metadata (such as the runtime to use), the app itself, and any dependencies that are not available in the runtime (which the app vendor is responsible for updating if necessary). However, the primary way to distribute and upgrade runtimes and applications is to package them as OSTree repositories, which provide a git-like content-addressed filesystem, with efficient updates using binary deltas. The resulting files are hard-linked into place. To address the last point, application bundles run partially isolated from the wider system, using containerization techniques such as namespaces to prevent direct access to system resources. Resources from outside the sandbox can be accessed via "portal" services, which are responsible for access control; for example, the Documents portal (the only one, so far) displays an "Open" dialog outside the sandbox, then allows the application to access only the selected file. xdg-app for Debian One thing I've been doing at this hackfest is improving the existing Debian/Ubuntu packaging for xdg-app (and its dependencies ostree and libgsystem), aiming to get it into a state where I can upload it to Debian experimental. Because xdg-app aims to be a general freedesktop project, I'm currently intending to make it part of the "Utopia" packaging team alongside projects like D-Bus and polkit, but I'm open to suggestions if people want to co-maintain it elsewhere. In the process of updating xdg-app, I sent various patches to Alex, mostly fixing build and test issues, which are in the new 0.4.8 release. I'd appreciate co-maintainers and further testing for this stuff, particularly ostree: ostree is primarily a whole-OS deployment technology, which isn't a use-case that I've tested, and in particular ostree-grub2 probably doesn't work yet. Source code:

• https://anonscm.debian.org/cgit/users/smcv/libgsystem.git
• https://anonscm.debian.org/cgit/users/smcv/ostree.git
• https://anonscm.debian.org/cgit/users/smcv/xdg-app.git

Binaries (no trust path, so only use these if you have a test VM):

• deb https://people.debian.org/~smcv/xdg-app xdg-app main

The "Hello, World" of xdg-apps Another thing I set out to do here was to make a runtime and an app out of Debian packages. Most of the test applications in and around GNOME use the "freedesktop" or "GNOME" runtimes, which consist of a Yocto base system and lots of RPMs, are rebuilt from first principles on-demand, and are extensive and capable enough that they make it somewhat non-obvious what's in an app or a runtime. So, here's a step-by-step route through xdg-app, first using typical GNOME instructions, but then using the simplest GUI app I could find - xvt, a small xterm clone. I'm using a Debian testing (stretch) x86_64 virtual machine for all this. xdg-app currently requires systemd-logind to put users and apps in cgroups, either with systemd as pid 1 (systemd-sysv) or systemd-shim and cgmanager; I used the default systemd-sysv. In principle it could work with plain cgmanager, but nobody has contributed that support yet. Demonstrating an existing xdg-app Debian's kernel is currently patched to be able to allow unprivileged users to create user namespaces, but make it runtime-configurable, because there have been various security issues in that feature, making it a security risk for a typical machine (and particularly a server). Hopefully unprivileged user namespaces will soon be secure enough that we can enable them by default, but for now, we have to do one of three things to let xdg-app use them:

• enable unprivileged user namespaces via sysctl:

  sudo sysctl kernel.unprivileged_userns_clone=1
  

• make xdg-app root-privileged (it will keep CAP_SYS_ADMIN and drop the rest):

  sudo dpkg-statoverride --update --add root root 04755 /usr/bin/xdg-app-helper
  

• make xdg-app slightly less privileged:

  sudo setcap cap_sys_admin+ep /usr/bin/xdg-app-helper
  

First, we'll need a runtime. The standard xdg-app tutorial would tell you to download the "GNOME Platform" version 3.18. To do that, you'd add a remote, which is a bit like a git remote, and a bit like an apt repository:

$ wget http://sdk.gnome.org/keys/gnome-sdk.gpg
$ xdg-app remote-add --user --gpg-import=gnome-sdk.gpg gnome \
    http://sdk.gnome.org/repo/

(I'm ignoring considerations like trust paths and security here, for brevity; in real life, you'd want to obtain the signing key via https and/or have a trust path to it, just like you would for a secure-apt signing key.) You can list what's available in a remote:

$ xdg-app remote-ls --user gnome
...
org.freedesktop.Platform
...
org.freedesktop.Platform.Locale.cy
...
org.freedesktop.Sdk
...
org.gnome.Platform
...

The Platform runtimes are what we want here: they are collections of runtime libraries with which you can run an application. The Sdk runtimes add development tools, header files, etc. to be able to compile apps that will be compatible with the Platform. For now, all we want is the GNOME 3.18 platform:

$ xdg-app install --user gnome org.gnome.Platform 3.18

Next, we can install an app that uses it, from Alex Larsson's nightly builds of a subset of GNOME. The server they're on doesn't have a great deal of bandwidth, so be nice :-)

$ wget http://209.132.179.2/keys/nightly.gpg
$ xdg-app remote-add --user --gpg-import=nightly.gpg nightly \
    http://209.132.179.2/repo/
$ xdg-app install --user nightly org.mypaint.MypaintDevel

We now have one app, and the runtime it needs:

$ xdg-app list
org.mypaint.MypaintDevel
$ xdg-app run org.mypaint.MypaintDevel
[you see a GUI window]

Digression: what's in a runtime? Behind the scenes, xdg-app runtimes and apps are both OSTree trees. This means the ostree tool, from the package of the same name, can be used to inspect them.

$ sudo apt install ostree
$ ostree refs --repo ~/.local/share/xdg-app/repo
gnome:runtime/org.gnome.Platform/x86_64/3.18
nightly:app/org.mypaint.MypaintDevel/x86_64/master

A "ref" has roughly the same meaning as in git: something like a branch or a tag. ostree can list the directory tree that it represents:

$ ostree ls --repo ~/.local/share/xdg-app/repo \
    runtime/org.gnome.Platform/x86_64/3.18
d00755 0 0      0 /
-00644 0 0    493 /metadata
d00755 0 0      0 /files
$ ostree ls --repo ~/.local/share/xdg-app/repo \
    runtime/org.gnome.Platform/x86_64/3.18 /files
d00755 0 0      0 /files
l00777 0 0      0 /files/local -> ../var/usrlocal
l00777 0 0      0 /files/sbin -> bin
d00755 0 0      0 /files/bin
d00755 0 0      0 /files/cache
d00755 0 0      0 /files/etc
d00755 0 0      0 /files/games
d00755 0 0      0 /files/include
d00755 0 0      0 /files/lib
d00755 0 0      0 /files/lib64
d00755 0 0      0 /files/libexec
d00755 0 0      0 /files/share
d00755 0 0      0 /files/src

You can see that /files in a runtime is basically a copy of /usr. This is not coincidental: the runtime's /files gets mounted at /usr inside the xdg-app container. There is also some metadata, which is in the ini-like syntax seen in .desktop files:

$ ostree cat --repo ~/.local/share/xdg-app/repo \
    runtime/org.gnome.Platform/x86_64/3.18 /metadata
[Runtime]
name=org.gnome.Platform/x86_64/3.16
runtime=org.gnome.Platform/x86_64/3.16
sdk=org.gnome.Sdk/x86_64/3.16
[Extension org.freedesktop.Platform.GL]
version=1.2
directory=lib/GL
[Extension org.freedesktop.Platform.Timezones]
version=1.2
directory=share/zoneinfo
[Extension org.gnome.Platform.Locale]
directory=share/runtime/locale
subdirectories=true
[Environment]
GI_TYPELIB_PATH=/app/lib/girepository-1.0
GST_PLUGIN_PATH=/app/lib/gstreamer-1.0
LD_LIBRARY_PATH=/app/lib:/usr/lib/GL

Looking at an app, the situation is fairly similar:

$ ostree ls --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master
d00755 0 0      0 /
-00644 0 0    258 /metadata
d00755 0 0      0 /export
d00755 0 0      0 /files

This time, /files maps to what will become /app for the application, which was compiled with --prefix=/app:

$ ostree ls --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master /files
d00755 0 0      0 /files
-00644 0 0   4599 /files/manifest.json
d00755 0 0      0 /files/bin
d00755 0 0      0 /files/lib
d00755 0 0      0 /files/share

There is also a /export directory, which is made visible to the host system so that the contained app can appear as a "first-class citizen" in menus:

$ ostree ls --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master /export
d00755 0 0      0 /export
d00755 0 0      0 /export/share
user@debian:~$ ostree ls --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master /export/share
d00755 0 0      0 /export/share
d00755 0 0      0 /export/share/app-info
d00755 0 0      0 /export/share/applications
d00755 0 0      0 /export/share/icons
user@debian:~$ ostree ls --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master /export/share/applications
d00755 0 0      0 /export/share/applications
-00644 0 0    715 /export/share/applications/org.mypaint.MypaintDevel.desktop
$ ostree cat --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master \
    /export/share/applications/org.mypaint.MypaintDevel.desktop
[Desktop Entry]
Version=1.0
Name=(Nightly) MyPaint
TryExec=mypaint
Exec=mypaint %f
Comment=Painting program for digital artists
...
Comment[zh_HK]= 
GenericName=Raster Graphics Editor
GenericName[fr]= diteur d'Image Matricielle
MimeType=image/openraster;image/png;image/jpeg;
Type=Application
Icon=org.mypaint.MypaintDevel
StartupNotify=true
Categories=Graphics;GTK;2DGraphics;RasterGraphics;
Terminal=false

Again, there's some metadata:

$ ostree cat --repo ~/.local/share/xdg-app/repo \
    app/org.mypaint.MypaintDevel/x86_64/master /metadata
[Application]
name=org.mypaint.MypaintDevel
runtime=org.gnome.Platform/x86_64/3.18
sdk=org.gnome.Sdk/x86_64/3.18
command=mypaint
[Context]
shared=ipc;
sockets=x11;pulseaudio;
filesystems=host;
[Extension org.mypaint.MypaintDevel.Debug]
directory=lib/debug

Building a runtime, probably the wrong way The way in which the reference/demo runtimes and containers are generated is... involved. As far as I can tell, there's a base OS built using Yocto, and the actual GNOME bits come from RPMs. However, we don't need to go that far to get a working runtime. In preparing this runtime I'm probably completely ignoring some best-practices and tools - but it works, so it's good enough. First we'll need a repository:

$ sudo install -d -o$(id -nu) /srv/xdg-apps
$ ostree init --repo /srv/xdg-apps

I'm just keeping this local for this demonstration, but you could rsync it to a web server's exported directory or something - a lot like a git repository, it's just a collection of files. We want everything in /usr because that's what xdg-app expects, hence usrmerge:

$ sudo mount -t tmpfs -o mode=0755 tmpfs /mnt
$ sudo debootstrap --arch=amd64 --include=libx11-6,usrmerge \
    --variant=minbase stretch /mnt http://192.168.122.1:3142/debian
$ sudo mkdir /mnt/runtime
$ sudo mv /mnt/usr /mnt/runtime/files

This obviously has a lot of stuff in it that we don't need - most obviously init, apt and dpkg - but it's Good Enough . We will also need some metadata. This is sufficient:

$ sudo sh -c 'cat > /mnt/runtime/metadata'
[Runtime]
name=org.debian.Debootstrap/x86_64/8.20160130
runtime=org.debian.Debootstrap/x86_64/8.20160130

That's a runtime. We can commit it to ostree, and generate xdg-app metadata:

$ ostree commit --repo /srv/xdg-apps \
    --branch runtime/org.debian.Debootstrap/x86_64/8.20160130 \
    /mnt/runtime
$ fakeroot ostree commit --repo /srv/xdg-apps \
    --branch runtime/org.debian.Debootstrap/x86_64/8.20160130
$ fakeroot xdg-app build-update-repo /srv/xdg-apps

(I'm not sure why ostree and xdg-app report "Operation not permitted" when we aren't root or fakeroot - feedback welcome.) build-update-repo would presumably also be the right place to GPG-sign your repository, if you were doing that. We can add that as another xdg-app remote:

$ xdg-app remote-add --user --no-gpg-verify local file:///srv/xdg-apps
$ xdg-app remote-ls --user local
org.debian.Debootstrap

Building an app, probably the wrong way The right way to build an app is to build a "SDK" runtime - similar to that platform runtime, but with development files and tools - and recompile the app and any missing libraries with ./configure --prefix=/app && make && make install. I'm not going to do that, because simplicity is nice, and I'm reasonably sure xvt doesn't actually hard-code /usr into the binary:

$ install -d xvt-app/files/bin
$ sudo apt-get --download-only install xvt
$ dpkg-deb --fsys-tarfile /var/cache/apt/archives/xvt_2.1-20.1_amd64.deb \
      tar -xvf - ./usr/bin/xvt
./usr/
./usr/bin/
./usr/bin/xvt
...
$ mv usr xvt-app/files

Again, we'll need metadata, and it's much simpler than the more production-quality GNOME nightly builds:

$ cat > xvt-app/metadata
[Application]
name=org.debian.packages.xvt
runtime=org.debian.Debootstrap/x86_64/8.20160130
command=xvt
[Context]
sockets=x11;
$ fakeroot ostree commit --repo /srv/xdg-apps \
    --branch app/org.debian.packages.xvt/x86_64/2.1-20.1 xvt-app
$ fakeroot xdg-app build-update-repo /srv/xdg-apps
Updating appstream branch
No appstream data for runtime/org.debian.Debootstrap/x86_64/8.20160130
No appstream data for app/org.debian.packages.xvt/x86_64/2.1-20.1
Updating summary
$ xdg-app remote-ls --user local
org.debian.Debootstrap
org.debian.packages.xvt

The obligatory screenshot OK, good, now we can install it:

$ xdg-app install --user local org.debian.Debootstrap 8.20160130
$ xdg-app install --user local org.debian.packages.xvt 2.1-20.1
$ xdg-app run --branch=2.1-20.1 org.debian.packages.xvt

and you can play around with the shell in the xvt and see what you can and can't do in the container. I'm sure there were better ways to do most of this, but I think there's value in having such a simplistic demo to go alongside the various GNOMEish apps.

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Acknowledgements:

• Betacowork Coworking Brussels and ICAB Business & Technology Incubator hosted the hackfest, with Collabora providing snacks, and the GNOME Foundation supporting the hackfest in general;
• Collabora also sponsored my travel, accommodation and time;
• my colleague Philip Withnall organised the hackfest.

Thanks to all those!

Long overdue, I finally enabled TLS on this blog. It went almost like a breeze. I used simp_le to get the certificate from Let s Encrypt, along Mozilla s Web Server Configuration generator. SSL Labs now reports a rating of A+. I just had a few issues:

• I had some hard-coded http:// links in my wordpress theme, that needed changes,
• Since my wordpress instance is reverse-proxied and the real server not behind HTTPS, I had to adjust the wordpress configuration so that it doesn t do an infinite redirect loop,
• Nginx s config for multiple virtualhosts needs SSL configuration to be repeated. Fortunately, one can use include statements,
• Contrary to the suggested configuration, setting ssl_session_tickets off; makes browsers unhappy (at least, it made my Firefox unhappy, with a SSL_ERROR_RX_UNEXPECTED_NEW_SESSION_TICKET error message).

I m glad that there are tools helping to get a proper configuration of SSL. It is sad, though, that the defaults are not better and that we still need to tweak at all. Setting where the certificate and the private key files are should, in 2016, be the only thing to do to have a secure web server.

Over the past two months or so I have become a contributor to the Debian Project. This is something that I ve wanted to do for a while. Firstly, just because I ve got so much out of Debian over the last five or six years both as a day-to-day operating system and a place to learn about computing and I wanted to contribute something back. And secondly, in following the work of Joey Hess for the past three or four years I ve come to share various technical and social values with Debian. Of course, I ve long valued the project of making it possible for people to run their computers entirely on Free Software, but more recently I ve come to appreciate how Debian s mature technical and social infrastructure makes it possible for a large number of people to work together to produce and maintain high quality packages. The end result is that the work of making a powerful software package work well with other packages on a Debian system is carried out by one person or a small team, and then as many users who want to make use of that software need only apt-get it. It s hard to get the systems and processes to make this possible right, especially without a team being paid full-time to set it all up. Debian has managed it on the backs of volunteers. That s something I want to be a part of. So far, most of my efforts have been confined to packaging addons for the Emacs text editor and the Firefox web browser. Debian has common frameworks for packaging these and lots of scripts that make it pretty easy to produce new packages (I did one yesterday in about 30 minutes). It s valuable to package these addons because there are a great many advantages for a user in obtaining them from their local Debian mirror rather than downloading them from the de facto Emacs addons repository or the Mozilla addons site. Users know that trusted Debian project volunteers have reviewed the software I cannot yet upload my packages to the Debian archive by myself and the whole Debian infrastructure for reporting and classifying bugs can be brought to bear. The quality assurance standards built into these processes are higher than your average addon author s, not that I mean to suggest anything about authors of the particular addons I ve packaged so far. And automating the installation of such addons is easy as there are all sorts of tools to automate installations of Debian systems and package sets. I hope that I can expand my work beyond packaging Emacs and Firefox addons in the future. It s been great, though, to build my general knowledge of the Debian toolchain and the project s social organisation while working on something that is both relatively simple and valuable to package. Now I said at the beginning of this post that it was following the work of Joey Hess that brought me to Debian development. One thing that worries me about becoming involved in more contentious parts of the Debian project is the dysfunction that he saw in the Debian decision-making process, dysfunction which eventually led to his resignation from the project in 2014. I hope that I can avoid getting quagmired and demotivated.

As you can now see on phpMyAdmin's security page, we've managed to spend 9 security announcements on todays release. Hopefully it won't continue that bad in rest of the year. Anyway receiving such extensive report was really challenging for us - correctly tracking and fixing all reported issues, discovering which versions are affected. This proven to be quite difficult given that most of the affected code has been refactored meanwhile. But I'm quite happy we've managed to fix ll issues on three supported branches in two weeks. Another challenge (especially for Isaac) was that this all came with change of our release manager, so forgive us some minor problems with the releases (especially not updated changelogs), we will do it better next time! PS: Updated packages are on their way to Debian and phpMyAdmin PPA. PS2: It seems we've messed few more things, so expect quick followup releases for older versions.

Filed under: Debian English phpMyAdmin 4 comments

Lets Encrypt is a new service to provide free SSL keys [1]. I ve just set it up on a few servers that I run. Issues The first thing to note is that the client is designed to manage your keys and treat all keys on a server equally with a single certificate. It shouldn t be THAT difficult to do things in other ways but it would involve extra effort. The next issue that can make things difficult is that it is designed that the web server will have a module to negotiate new keys automatically. Automatically negotiating new keys will be really great when we get that all going, but as I didn t feel like installing a slightly experimental Apache module on my servers that meant I had to stop Apache while I got the keys and I ll have to do that again every 3 months as the keys have a short expiry time. There are some other ways of managing keys, but the web servers I m using Lets Encrypt with at the moment aren t that important and a couple of minutes of downtime is acceptable. When you request multiple keys (DNS names) for one server to make it work without needless effort you have to get them all in the one operation. That gives you a single key file for all DNS names which is very convenient for services that don t support getting the hostname before negotiating SSL. But it could be difficult if you wanted to have one of the less common configurations such as having a mail server and a web server on the same IP addess but using different keys How To Get Keys deb http://mirror.internode.on.net/pub/debian/ testing main The letsencrypt client is packaged for Debian in Testing but not in Jessie. Adding the above to the /etc/apt/sources.list file for a Jessie system allows installing it and a few dependencies from Testing. Note that there are problems with doing this, you can t be certain that all the other apps installed will be compatible with the newer versions of libraries that are installed and you won t get security updates. letsencrypt certonly --standalone-supported-challenges tls-sni-01 The above command makes the letsencrypt client listen on port 443 to talk to the Lets Encrypt server. It prompts you for server names so if you want to minimise the downtime for your web server you could specify the DNS names on the command-line. If you run it on a SE Linux system you need to run setsebool allow_execmem 1 before running it and setsebool allow_execmem 0 afterwards as it needs execmem access. I don t think it s a problem to temporarily allow execmem access for the duration of running this program, if you use KDE then you will be forced to allow such access all the time for the desktop to operate correctly. How to Install Keys [ssl:emerg] [pid 9361] AH02564: Failed to configure encrypted (?) private key www.example.com:443:0, check /etc/letsencrypt/live/www.example.com/fullchain.pem The letsencrypt client suggests using the file fullchain.pem which has the key and the full chain of certificates. When I tried doing that I got errors such as the above in my Apache error.log. So I gave up on that and used the separate files. The only benefit of using the fullchain.pem file is to have a single line in a configuration file instead of 3. Trying to debug issues with fullchain.pem took me a lot longer than copy/paste for the 3 lines. Under /etc/letsencrypt/live/$NAME there are symlinks to the real files. So when you get new keys the old keys will be stored but the same file names can be used. SSLCertificateFile "/etc/letsencrypt/live/www.example.com/cert.pem"
SSLCertificateChainFile "/etc/letsencrypt/live/www.example.com/chain.pem"
SSLCertificateKeyFile "/etc/letsencrypt/live/www.example.com/privkey.pem" The above commands are an example for configuring Apache 2. smtpd_tls_cert_file = /etc/letsencrypt/live/smtp.example.com/cert.pem
smtpd_tls_key_file = /etc/letsencrypt/live/smtp.example.com/privkey.pem
smtpd_tls_CAfile = /etc/letsencrypt/live/smtp.example.com/chain.pem Above is an example of Postfix configuration. ssl_cert = </etc/letsencrypt/live/smtp.example.com/cert.pem
ssl_key = </etc/letsencrypt/live/smtp.example.com/privkey.pem
ssl_ca = </etc/letsencrypt/live/smtp.example.com/chain.pem Above is an example for Dovecot, it goes in /etc/dovecot/conf.d/10-ssl.conf in a recent Debian version. Conclusion At this stage using letsencrypt is a little fiddly so for some commercial use (where getting the latest versions of software in production is difficult) it might be a better option to just pay for keys. However some companies I ve worked for have had issues with getting approval for purchases which would make letsencrypt a good option to avoid red tape. When Debian/Stretch is released with letsencrypt I think it will work really well for all uses.

• [1] https://letsencrypt.org/