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Përditësimi: 3 months 3 javë më parë

FOSScamp Syros 2017 – day 1

Dje, 03/09/2017 - 9:09md

During Debconf17 I was asked by Daniel Pocock if I can attend FOSScamp Syros to help with Debian’s l10n in the Balkans. I said I would be happy to, although my visit would be short (2.5 days) due to previous plans. The main idea of camp is to have FOSS people meet for about 1 week near a beach. So it’s sun, water and free software.  This year it takes place  in Syros, Greece.

After take the morning ferry, I met with the guys at noon. I didn’t know how would it be, as it’s my first time with this group/meeting, but they were very nice and welcoming. 10 minutes after my arrival I found myself setting with two of the female attendees starting to work on Albanian (sq) translation of Debian Installer.

It took my a few minutes to find my where to check out the current level1 files, as I thought they aren’t in SVN anymore, but ended up learning the PO files is the only part of the installer still on SVN. As the girls were quick with the assinged levle1 sublevels, I started to look for the level2 and level3 files, and it was annoying to have the POT files very accessible, but no links to the relevant git repositories. I do want to have all the relevant links in one central place, so people who want to help with translation could do that.

While some of the team member just used a text editor to edit the files, I suggested to them using either poedit or granslator, both I used a few years ago. Yaron Shahrabani also recommended virtaal to me, but after trying it for a while I didn’t like it (expect it’s great feature showing the diff with fuzzy messages). For the few people who also have Windows on their machine, both poedit and Virtaal have windows binaries for download. So you don’t have to have Linux in order to help with translations.

In parallel, I used the “free” time to work on the Hebrew translation for level1, as it’s been a while since either me or Omer Zak worked on it. Quite soon the guys started to send me the files for review, and I did find some errors using diff. Especially when not everyone use a PO editor. I also missed a few strings during the review, which got fixed later on by Christian Perrier. Team work indeed (:

I found it interesting to see the reactions and problems for the team to work with the PO files, and most projects now use some system (e.g. Pootle) for online web translation. Which saves some of the head ace, but also prevents from making some review and quality check before submitting the files. It’s a good idea to explore this option for Debian as well.

A tip for those who do want to work with PO files, either use git’s diff features or use colordiff to check your changes (notice less will require -R parameter to keep the color).

Although I met the guys only at noon, the day was very fruitful for Debian Installer l10n:

  • Albanian (sq) level1 – from 78% to 82% (Eva Vranici, Silva Arapi)
  • Albanian (sq) level2 – from 20% to 24% (Nafie Shehu)
  • Hebrew (he) level1 – from 96% to 97% (me)
  • Greek (el) level1 – from 96% to 97% (Sotirios Vrachas)

Some files are still work in progress and will be completed tomorrow. My goal is to have Albanian at 100% during the camp and ready for the next d-i alpha.

I must admit that I remember d-i to have many more strings as part of the 3 levels, especially levels 2+3 which were huge (e.g. the iso codes).

Except all the work and FOSS related conversations, I found a great group who welcomed me quickly, made me feel comfortable and taught me a thing or two about Greece and the Syros specifically.

TIP: try the dark chocolate with red hot chili pepper in the icecream shop.


Filed under: Debian GNU/Linux, i18n & l10n Kaplan https://liorkaplan.wordpress.com Free Software Universe

My Debian Activities in August 2017

Dje, 03/09/2017 - 8:10md

FTP assistant

This month I accepted 217 packages and rejected 16 uploads. Though this might seem to be a low number this month, I am very pleased about the total number of packages that have been accepted: 558.

Debian LTS

This was my thirty-eight month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian.

This month my all in all workload has been 20.25h. During that time I did LTS uploads of:

  • [DLA 1055-1] libgd2 security update for one CVE
  • [DLA 1060-1] libxml2 security update for two CVEs
  • [DLA 1062-1] curl security update for one CVE
  • [DLA 1063-1] extplorer security update for one CVE
  • [DLA 1065-1] fontforge security update for 8 CVEs
  • [DLA 1082-1] graphicsmagick security update for 8 CVEs

I also did the upload and sent the DLA for [DLA 1061-1] newsbeuter security update

Last but not least I also spent some time for frontdesk duties.

Other stuff

As announced last month I finished uploading all dependencies of glewlwyd and now we have an oauth2 server available in Debian. This month I am trying to really use it and will tell you about my experiences.

As the severity of the gcc-7 bugs have been raised, I took care of: #853501, #853304, #853305, #853306, #853307, #853308 and #871088

I also uploaded a new version of duktape and now try to also provide a library that can be used in other packages.

Last but not least my DOPOM of this month has been oysttyer. Actually it is a new package, but as ttytter has been abandonded upstream, this is the replacement. It is a fork so you should only get a new authorization key and simply use it as ttytter before.

alteholz http://blog.alteholz.eu blog.alteholz.eu » planetdebian

Indexing Debian's buildinfo

Sht, 02/09/2017 - 10:41md
Introduction

Debian is currently collecting buildinfo but they are not very conveniently searchable. Eventually Chris Lamb's buildinfo.debian.net may solve this problem, but in the mean time, I decided to see how practical indexing the full set of buildinfo files is with sqlite.

Hack
  1. First you need a copy of the buildinfo files. This is currently about 2.6G, and unfortunately you need to be a debian developer to fetch it.

    $ rsync -avz mirror.ftp-master.debian.org:/srv/ftp-master.debian.org/buildinfo .
  2. Indexing takes about 15 minutes on my 5 year old machine (with an SSD). If you index all dependencies, you get a database of about 4G, probably because of my natural genius for database design. Restricting to debhelper and dh-elpa, it's about 17M.

    $ python3 index.py

    You need at least python3-debian installed

  3. Now you can do queries like

    $ sqlite3 depends.sqlite "select * from depends where depend='dh-elpa' and depend_version<='0106'"

    where 0106 is some adhoc normalization of 1.6

Conclusions

The version number hackery is pretty fragile, but good enough for my current purposes. A more serious limitation is that I don't currently have a nice (and you see how generous my definition of nice is) way of limiting to builds currently available e.g. in Debian unstable.

David Bremner http://www.cs.unb.ca/~bremner//blog/tags/planet/ blog/tags/planet

My free software activities, August 2017

Sht, 02/09/2017 - 10:16md
Debian Long Term Support (LTS)

This is my monthly Debian LTS report. This month I worked on a few major packages that took a long time instead of multiple smaller issues. Affected packages were Mercurial, libdbd-mysql-perl and Ruby.

Mercurial updates

Mercurial was vulnerable to two CVEs: CVE-2017-1000116 (command injection on clients through malicious ssh URLs) and CVE-2017-1000115 (path traversal via symlink). The former is an issue that actually affects many other similar software like Git (CVE-2017-1000117), Subversion (CVE-2017-9800) and even CVS (CVE-2017-12836). The latter symlink issue is a distinct issue that came up during an internal audit.

The fix, shipped as DLA-1072-1, involved a rather difficult backport, especially because the Mercurial test suite takes a long time to complete. This reminded me of the virtues of DEB_BUILD_OPTIONS=parallel=4, which sped up the builds considerably. I also discovered that the Wheezy build chain doesn't support sbuild's --source-only-changes flag which I had hardcoded in my sbuild.conf file. This seems to be simply because sbuild passes --build=source to dpkg-buildpackage, an option that is supported only in jessie or later.

libdbd-mysql-perl

I have worked on fixing two issues with the libdbd-mysql-perl package, CVE-2017-10788 and CVE-2017-10789, which resulted in the DLA-1079-1 upload. Behind this mysteriously named package sits a critical piece of infrastructure, namely the mysql commandline client which is probably used and abused by hundreds if not thousands of home-made scripts, but also all of Perl's MySQL support, which is probably used by even a larger base of software.

Through the Debian bug reports (Debian bug #866818 and Debian bug #866821), I have learned that the patches existed in the upstream tracker but were either ignored or even reverted in the latest 4.043 upstream release. It turns out that there are talks of forking that library because of maintainership issue. It blows my mind that such an important part of MySQL is basically unmaintained.

I ended up backporting the upstream patches, which was also somewhat difficult because of the long-standing issues with SSL support in MySQL. The backport there was particularly hard to test, as you need to run that test suite by hand, twice: once with a server configured with a (valid!) SSL certificate and one without (!). I'm wondering how much time it is really worth spending on trying to fix SSL in MySQL, however. It has been badly broken forever, and while the patch is an improvement, I would actually still never trust SSL transports in MySQL over an untrusted network. The few people that I know use such transports wrap their connections around a simpler stunnel instead.

The other issue was easier to fix so I submitted a pull request upstream to make sure that work isn't lost, although it is not clear what the future of that patch (or project!) will be at this point.

Rubygems

I also worked on the rubygems issues, which, thanks to the "vendoring" practice of the Ruby community, also affects the ruby1.9 package. 4 distinct CVEs were triaged here (CVE-2017-0899, CVE-2017-0900, CVE-2017-0901 and CVE-2017-0902) and I determined the latter issue didn't affect wheezy as rubygems doesn't do its own DNS resolution there (later versions lookup SRV records).

This is another package where the test suite takes a long time to run. Worse, the packages in Wheezy actually fails to build from source: the test suites just fail in various steps, particularly because of dh key too small errors for Rubygems, but also other errors for Ruby. I also had trouble backporting one test which I had to simply skip for Rubygems. I uploaded and announced test packages and hopefully I'll be able to complete this work soon, although I would certainly appreciate any help on this...

Triage

I took a look at the sox, libvorbis and exiv2 issues. None had fixes available. sox and exiv2 were basically a list of fuzzing issues, which are often minor or at least of unknown severity. Those would have required a significant amount of work and I figured I would prioritize other work first.

I also triaged CVE-2017-7506, which doesn't seem to affect the spice package in wheezy, after doing a fairly thorough audit of the code. The vulnerability is specifically bound to the reds_on_main_agent_monitors_config function, which is simply not present in our older version. A hostile message would fall through the code and not provoke memory allocation or out of bounds access, so I simply marked the wheezy version as not-affected, something which usually happens during the original triage but can also happen during the actual patching work, as in this case.

Other free software work

This describes the volunteer work I do on various free software projects. This month, again, my internal reports show that I spent about the same time on volunteer and paid time, but this is probably a wrong estimate because I spent a lot of time at Debconf which I didn't clock in...

Debconf

So I participated in the 17th Debian Conference in Montreal. It was great to see (and make!) so many friends from all over the world in person again, and I was happy to work on specific issues together with other Debian developers. I am especially thankful to David Bremner for fixing the syncing of the flagged tag when added to new messages (patch series). This allows me to easily sync the one tag (inbox) that is not statically assigned during notmuch new, by using flagged as a synchronization tool. This allows me to use notmuch more easily across multiple machines without having to sync all tags with dump/restore or using muchsync which wasn't working for me (although a new release came out which may fix my issues). The magic incantation looks something like this:

notmuch tag -inbox tag:inbox and not tag:flagged notmuch tag +inbox not tag:inbox and tag:flagged

However, most of my time in the first week (Debcamp) was spent trying to complete the networking setup: configure switches, setup wiring and so on. I also configured an apt-cacher-ng proxy to serve packages to attendees during the conference. I configured it with Avahi to configure clients automatically, which led me to discover (and fix) issue Debian bug #870321) although there are more issues with the autodiscovery mechanism... I spent extra time to document the (somewhat simple) configuration of such a server in the Debian wiki because it was not the first time I had research that procedure...

I somehow thought this was a great time to upgrade my laptop to stretch. Normally, I keep that device running stable because I don't use it often and I don't want to have major traumatizing upgrades every time I leave with it on a trip. But this time was special: there were literally hundreds of Debian developers to help me out if there was trouble. And there was, of course, trouble as it turns out! I had problems with the fonts on my display, because, well, I had suspended (twice) my laptop during the install. The fix was simply to flush the fontconfig cache, and I tried to document this in the fonts wiki page and my upgrades page.

I also gave a short training called Debian packaging 101 which was pretty successful. Like the short presentation I made at the last Montreal BSP, the workshop was based on my quick debian development guide. I'm thinking of expanding this to a larger audience with a "102" course that would discuss more complex packaging problems. But my secret plan (well, secret until now I guess) is to make packaging procedures more uniform in Debian by training new Debian packagers using that same training for the next 2 decades. But I will probably start by just trying to do this again at the next Debconf, if I can attend.

Debian uploads

I also sponsored two packages during Debconf: one was a "scratch an itch" upload (elpa-ivy) which I requested (Debian bug #863216) as part of a larger effort to ship the Emacs elisp packages as Debian packages. The other was an upload of diceware to build the documentation in a separate package and fix other issues I have found in the package during a review.

I also uploaded a bunch of other fixes to the Debian archive:

Signing keys rotation

I also started the process of moving my main OpenPGP certification key by adding a signing subkey. The subkey is stored in a cryptographic token so I can sign things on more than one machine without storing that critical key on all those devices physically.

Unfortunately, this meant that I need to do some shenanigans when I want to sign content in my Debian work, because the new subkey takes time to propagate to the Debian archive. For example, I have to specify the primary key with a "bang" when signing packages (debsign -k '792152527B75921E!' ...) or use inline signatures in email sent for security announcement (since that trick doesn't work in Mutt or Notmuch). I tried to figure out how to better coordinate this next time by reading up documentation on keyring.debian.org, but there is no fixed date for key changes on the rsync interface. There are "monthly changes" so one's best bet is to look for the last change in their git repository.

GitLab.com and LFS migration

I finally turned off my src.anarc.at git repository service by moving the remaining repos to GitLab. Unfortunately, GitLab removed support for git-annex recently, so I had to migrate my repositories to Git-LFS, which was an interesting experience. LFS is pretty easy to use, definitely simpler than git-annex. It also seems to be a good match for the use-case at hand, which is to store large files (videos, namely) as part of slides for presentations.

It turns out that their migration guide could have been made much simpler. I tried to submit those changes to the documentation but couldn't fork the GitLab EE project to make a patch, so I just documented the issue in the original MR for now. While I was there I filed a feature request to add a new reference shortcut (GL-NNN) after noticing a similar token used on GitHub. This would be a useful addition because I often have numbering conflicts between Debian BTS bug numbers and GitLab issues in packages I maintain there. In particular, I have problems using GitLab issue numbers in Monkeysign, because commit logs end up in Debian changelogs and will be detected by the Debian infrastructure even though those are GitLab bug numbers. Using such a shortcut would avoid detection and such a conflict.

Numpy-stats

I wrote a small tool to extract numeric statistics from a given file. I often do ad-hoc benchmarks where I store a bunch of numbers in a file and then try to make averages and so on. As an exercise in learning NumPy, I figured I would write such a simple tool, called numpy-stats, which probably sounds naive to seasoned Python scientists.

My incentive was that I was trying to figure out what was the distribution of password length in a given password generator scheme. So I wrote this simple script:

for i in seq 10000 ; do shuf -n4 /usr/share/dict/words | tr -d '\n' done > length

And then feed that data in the tool:

$ numpy-stats lengths { "max": 60, "mean": 33.883293722913464, "median": 34.0, "min": 14, "size": 143060, "std": 5.101490225062775 }

I am surprised that there isn't such a tool already: hopefully I am wrong and will just be pointed towards the better alternative in the comments here!

Safe Eyes

I added screensaver support to the new SafeEyes project, which I am considering as a replacement to the workrave project I have been using for years. I really like how the interruptions basically block the whole screen: way more effective than only blocking the keyboard, because all potential distractions go away.

One feature that is missing is keystrokes and mouse movement counting and of course an official Debian package, although the latter would be easy to fix because upstream already has an unofficial build. I am thinking of writing my own little tool to count keystrokes, since the overlap between SafeEyes and such a counter isn't absolutely necessary. This is something that workrave does, but there are "idle time" extensions in Xorg that do not need to count keystrokes. There are already certain tools to count input events, but none seem to do what I want (most of them are basically keyloggers). It would be an interesting test to see if it's possible to write something that would work both for Xorg and Wayland at the same time. Unfortunately, preliminary research show that:

  1. in Xorg, the only way to implement this is to sniff all events, ie. to implement a keylogger

  2. in Wayland, this is completely unsupported. it seems some compositors could implement such a counter, but then it means that this is compositor specific, or, in other words, unportable

So there is little hope here, which brings to my mind "painmeter" as an appropriate name for this future programming nightmare.

Ansible

I sent my first contribution to the ansible project with a small documentation fix. I had an eye opener recently when I discovered a GitLab ansible prototype that would manipulate GitLab settings. When I first discovered Ansible, I was frustrated by the YAML/Jinja DSL: it felt silly to write all this code in YAML when you are a Python developer. It was great to see reasonably well-written Python code that would do things and delegate the metadata storage (and only that!) to YAML, as opposed to using YAML as a DSL.

So I figured I would look at the Ansible documentation on how this works, but unfortunately, the Ansible documentation is severly lacking in this area. There are broken links (I only fixed one page) and missing pieces. For example, the developing plugins page doesn't explain how to program a plugin at all.

I was told on IRC that: "documentation around developing plugins is sparse in general. the code is the best documentation that exists (right now)". I didn't get a reply when asking which code in particular could provide good examples either. In comparison, Puppet has excellent documentation on how to create custom types, functions and facts. That is definitely a turn-off for a new contributor, but at least my pull request was merged in and I can only hope that seasoned Ansible contributors expand on this critical piece of documentation eventually.

Misc

As you can see, I'm all over the place, as usual. GitHub tells me I "Opened 13 other pull requests in 11 repositories" (emphasis mine), which I guess means on top of the "9 commits in 5 repositories" mentioned earlier. My profile probably tells a more detailed story that what would be useful to mention here. I should also mention how difficult it is to write those reports: I basically do a combination of looking into my GitHub and GitLab profiles, the last 30 days of emails and filesystem changes (!!). En vrac, a list of changes which may be of interest:

  • font-large (and its alias, font-small): shortcut to send the right escape sequence to rxvt so it changes its font
  • fix-acer: short script to hardcode the modeline (you remember those?!) for my screen which has a broken EDID pin (so autodetection fails, yay Xorg log files...)
  • ikiwiki-pandoc-quickie: fake ikiwiki renderer that (ab)uses pandoc to generate a HTML file with the right stylesheet to preview Markdown as it may look in this blog (the basic template is missing still)
  • git-annex-transfer: a command I've often been missing in git-annex, which is a way to transfer files between remotes without having to copy them locally (upstream feature request)
  • I linked the graphics of the Debian archive software architecture in the Debian wiki in the hope more people notice it.
  • I did some tweaks on my Taffybar to introduce a battery meter and hoping to have temperature sensors, which mostly failed. there's a pending pull request that may bring some sense into this, hopefully.
  • I made two small patches in Monkeysign to fix gpg.conf handling and multiple email output, a dumb bug I cannot believe anyone noticed or reported just yet. Thanks Valerie for the bug report! The upload of this in Debian is pending a review from the release team.
Antoine Beaupré http://anarc.at/tag/debian-planet/ pages tagged debian-planet

Playing with Moose and FFmpeg

Sht, 02/09/2017 - 6:12md

As I've blogged before, I've been on and off working on SReview, a video review system. Development over the past year has been mostly driven by the need to have something up and running for first FOSDEM 2017, and then DebConf17, and so I've cut corners left and right which made the system, while functional, not quite entirely perfect everywhere. For instance, the backend scripts were done in ad-hoc perl, each reinventing their own wheel. Doing so made it easier for me to experiment with things and figure out where I want them to go, without immediately creating a lot of baggage that is not necessarily something I want to be stuck to. This flexibility has already paid off, in that I've redone the state machine between FOSDEM and DebConf17—and all it needed was to update a few SQL statements here and there. Well, and add a few of them, too.

It was always the intent to replace most of the ad-hoc perl with something better, however, once the time was ripe. One place where historical baggage is not so much of a problem, and where in fact abstracting away the complexity would now be an asset, is in the area of FFmpeg command lines. Currently, these are built by simple string expansion. For example, we do something like this (shortened for brevity):

system("ffmpeg -y -i $outputdir/$slug.ts -pass 1 -passlogfile ...");

inside an environment where the $outputdir and $slug variables are set in a perl environment. That works, but it has some downsides; e.g., adding or removing options based on which codecs we're using is not so easy. It would be much more flexible if the command lines were generated dynamically based on requested output bandwidth and codecs, rather than that they be hardcoded in the file. Case in point: currently there are multiple versions of some of the backend scripts, that only differ in details—mostly the chosen codec on the ffmpeg command line. Obviously this is suboptimal.

Instead, we want a way where video file formats can be autodetected, so that I can just say "create a file that uses encoder etc settings of this other file here". In addition, we also want a way where we can say "create a file that uses encoder etc settings of this other file here, except for these one or two options that I want to fine-tune manually". When I first thought about doing that about a year ago, that seemed complicated and not worth it—or at least not to that extent.

Enter Moose.

The Moose OO system for Perl 5 is an interesting way to do object orientation in Perl. I knew Perl supports OO, and I had heard about Moose, but never had looked into it, mostly because the standard perl OO features were "good enough". Until now.

Moose has a concept of adding 'attributes' to objects. Attributes can be set at object construction time, or can be accessed later on by way of getter/setter functions, or even simply functions named after the attribute itself (the default). For more complicated attributes, where the value may not be known until some time after the object has been created, Moose borrows the concept of "lazy" variables from Perl 6:

package Object; use Moose; has 'time' => ( is => 'rw', builder => 'read_time', lazy => 1, ); sub read_time { return localtime(); }

The above object has an attribute 'time', which will not have a value initially. However, upon first read, the 'localtime()' function will be called, the result is cached, and then (and on all further calls of the same function), the cached result will be returned. In addition, since the attribute is read/write, the time can also be written to. In that case, any cached value that may exist will be overwritten, and if no cached value exists yet, the read_time function will never be called. (it is also possible to clear values if needs be, so that the function would be called again).

We use this with the following pattern:

package SReview::Video; use Moose; has 'url' => ( is => 'rw', ) has 'video_codec' => ( is => 'rw', builder => '_probe_videocodec', lazy => 1, ); has 'videodata' => ( is => 'bare', reader => '_get_videodata', builder => '_probe_videodata', lazy => 1, ); has 'probedata' => ( is => 'bare', reader => '_get_probedata', builder => '_probe', lazy => 1, ); sub _probe_videocodec { my $self = shift; return $self->_get_videodata->{codec_name}; } sub _probe_videodata { my $self = shift; if(!exists($self->_get_probedata->{streams})) { return {}; } foreach my $stream(@{$self->_get_probedata->{streams}}) { if($stream->{codec_type} eq "video") { return $stream; } } return {}; } sub _probe { my $self = shift; open JSON, "ffprobe -print_format json -show_format -show_streams " . $self->url . "|" my $json = ""; while(<JSON>) { $json .= $_; } close JSON; return decode_json($json); }

The videodata and probedata attributes are internal-use only attributes, and are therefore of the 'bare' type—that is, they cannot be read nor written to. However, we do add 'reader' functions that can be used from inside the object, so that the object itself can access them. These reader functions are generated, so they're not part of the object source. The probedata attribute's builder simply calls ffprobe with the right command-line arguments to retrieve data in JSON format, and then decodes that JSON file.

Since the passed JSON file contains an array with (at least) two streams—one for video and one for audio—and since the ordering of those streams depends on the file and is therefore not guaranteed, we have to loop over them. Since doing so in each and every attribute of the file we might be interested in would be tedious, we add a videodata attribute that just returns the data for the first found video stream (the actual source also contains a similar one for audio streams).

So, if you create an SReview::Video object and you pass it a filename in the url attribute, and then immediately run print $object->video_codec, then the object will

  • call ffprobe, and cache the (decoded) output for further use
  • from that, extract the video stream data, and cache that for further use
  • from that, extract the name of the used codec, cache it, and then return that name to the caller.

However, if the caller first calls $object->video_codec('h264'), then the ffprobe and most of the caching will be skipped, and instead the h265 data will be returned as video codec name.

Okay, so with a reasonably small amount of code, we now have a bunch of attributes that have defaults based on actual files but can be overwritten when necessary. Useful, right? Well, you might also want to care about the fact that sometimes you want to generate a video file that uses the same codec settings of this other file here. That's easy. First, we add another attribute:

has 'reference' => ( is => 'ro', isa => 'SReview::Video', predicate => 'has_reference' );

which we then use in the _probe method like so:

sub _probe { my $self = shift; if($self->has_reference) { return $self->reference->_get_probedata; } # original code remains here }

With that, we can create an object like so:

my $video = SReview::Video->new(url => 'file.ts'); my $generated = SReview::Video->new(url => 'file2.ts', reference => $video);

now if we ask the $generated object what the value of its video_codec setting is without telling it ourselves first, it will use the $video object for its probed data, and use that.

That only misses generating the ffmpeg command line, but that's all fairly straightforward and therefore left as an exercise to the reader. Or you can cheat, and look it up.

Wouter Verhelst https://grep.be/blog//pd/ pd

F/LOSS activity, August 2017

Sht, 02/09/2017 - 12:00md

Shockingly enough, my focus started out on Gitano once more. We managed a 1.1 release of Gitano during the Debian conference's "camp" which occurs in the week before the conference. This was a joint effort of myself, Richard Maw, and Richard Ipsum. I have to take my hat off to Richard Maw, because without his dedication to features, 1.1 would lack some stuff which Richard Ipsum proposed around ruleset support for basic readers/writers and frankly 1.1 would be a weaker release without it.

Because of the debconf situation, we didn't have a Gitano developer day which, while sad, didn't slow us down much...

  • Once again, we reviewed our current task state
  • I submitted a series which fixed our test suite for Git 2.13 which was an FTBFS bug submitted against the Debian package for Gitano. Richard Maw reviewed and merged it.
  • Richard Maw supplied a series to add testing for dangling HEAD syndrome. I reviewed and merged that.
  • Richard Maw submitted a patch to improve the auditability of the 'as' command and I reviewed and merged that.
  • Richard Ipsum submitted a patch to add reader/writer configs to ease simple project management in Gitano. I'm not proud to say that I was too busy to look at this and ended up saying it was unlikely it'd get in. Richard Maw, quite rightly, took umbrage at that and worked on the patch, eventually submitting a new series with tests which I then felt obliged to review and I merged the series eventually.

    This is an excellent example of where just because one person is too busy doesn't mean that a good idea should be dropped, and I am grateful to Richard Maw for getting this work mergeable and effectively guilt-tripping me into reviewing/merging. This is a learnable moment for me and I hope to do better into the future.

  • During all that time, I was working on a plugin to support git-multimail.py in Gitano. This work ranged across hooks and caused me to spend a long time thinking about the semantics of configuration overriding etc. Fortunately I got there in the end, and with a massive review effort from Richard Maw, we got it merged into Gitano.
  • Finally I submitted a patch which caused the tests we run in Gitano to run from an 'install' directory which ensures that we catch bugs such as those which happened in earlier series where we missed out rules files for installation etc. Richard Maw reviewed and merged that.
  • And then we released the new version of Gitano and subsidiary libraries.

    There was Luxio version 13 which switched us to readdir() from readdir_r() thanks to Richard Ipsum; Gall 1.3 which contained a bunch of build cleanups, and also a revparse_single() implementation in the C code to speed things up thanks to Richard Maw; Supple 1.0.8 which improved wrapper environment cleanups thanks to Richard Ipsum, allowed baking of paths in which means Nix is easier to support (again thanks to Richard Ipsum), fixed setuid handling so that Nix is easier to support (guess what? Richard Ipsum again); Lace 1.4 which now verifies definition names in allow/deny/anyof/allof and also produces better error messages from nested includes.

    And, of course, Gitano 1.1 whose changes were somewhat numerous and so you are invited to read them in the Gitano NEWS file for the release.

Not Gitano

Of course, not everything I did in August was Gitano related. In fact once I had completed the 1.1 release and uploaded everything to Debian I decided that I was going to take a break from Gitano until the next developer day. (In fact there's even some patch series still unread on the mailing list which I will get to when I start the developer day.)

I have long been interested in STM32 microcontrollers, using them in a variety of projects including the Entropy Key which some of you may remember. Jorge Aparicio was working on Cortex-M3 support (among other microcontrollers) in Rust and he then extended that to include a realtime framework called RTFM and from there I got interested in what I might be able to do with Rust on STM32. I noticed that there weren't any pure Rust implementations of the USB device stack which would be necessary in order to make a device, programmed in Rust, appear on a USB port for a computer to control/use. This tweaked my interest.

As many of my readers are aware, I am very bad at doing things without some external motivation. As such, I then immediately offered to give a talk at a conference which should be happening in November, just so that I'd be forced to get on with learning and implementing the stack. I have been chronicling my work in this blog, and you're encouraged to go back and read them if you have similar interests. I'm sure that as my work progresses, I'll be doing more and more of that and less of Gitano, for at least the next two months.

To bring that into context as F/LOSS work, I did end up submitting some patches to Jorge's STM32F103xx repository to support a couple more clock configuration entries so that USB and ADCs can be set up cleanly. So at least there's that.

Daniel Silverstone http://blog.digital-scurf.org/ Digital-Scurf Ramblings

Litigants

Sht, 02/09/2017 - 3:21pd

Bronwyn’s mom got hit by a semi. She was on the passenger side of the car, the side of impact, and she did not rebound with extreme resilience. The family sued the trucking company and came away with a settlement of roughly $10 million. The lawyers took $6.5 million of that: quite a deal.

Bronwyn learned two things from this, and neither one was about Christopher Lloyd.

Posted on 2017-09-02 Tags: mintings C https://xana.scru.org Yammering

Good night moon and spoon balloon

Sht, 02/09/2017 - 1:17pd

“Hello,” said Adrian, but Adrian was lying.

“My name is Adrian,” said Adrian, but Adrian was lying.

Posted on 2017-09-01 Tags: bgs C https://xana.scru.org Yammering

New Debian Developers and Maintainers (July and August 2017)

Pre, 01/09/2017 - 8:30md

The following contributors got their Debian Developer accounts in the last two months:

  • Ross Gammon (rossgammon)
  • Balasankar C (balasankarc)
  • Roland Fehrenbacher (rfehren)
  • Jonathan Cristopher Carter (jcc)

The following contributors were added as Debian Maintainers in the last two months:

  • José Gutiérrez de la Concha
  • Paolo Greppi
  • Ming-ting Yao Wei
  • Boyuan Yang
  • Paul Hardy
  • Fabian Wolff
  • Moritz Schlarb
  • Shengjing Zhu

Congratulations!

Jean-Pierre Giraud https://bits.debian.org/ Bits from Debian

My Free Software Activities in August 2017

Pre, 01/09/2017 - 3:40md

My monthly report covers a large part of what I have been doing in the free software world. I write it for my donors (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

This month I was allocated 12h and during this time I did 4 days of front desk handling CVE triage (28 commits to the security tracker). I had a bit of time left and I opted to work on a package that had been lingering for a while: exiv2. It turns out the security researchers who requested the CVE did not even contact the upstream author so I opened 12 tickets on GitHub. The upstream author was unaware of those issues and is relatively unfamiliar with the general process of handling security updates. I started the work of reproducing each issue and so far they only affect the version 0.26 in experimental.

Misc Debian/Kali work

live-build and live-config. I pushed a few updates: dropping the useless xorriso –hardlinks option (as discussed in https://bugs.kali.org/view.php?id=4109), adding a .disk/mkisofs file on request of Thomas Schmitt, fixing a severe issue with the handling of locales configuration that broke wayland sessions entirely.

open-vm-tools and vmwgfx. The switch of GNOME to Wayland by default resulted in multiple regressions reported by Kali users, in particular for VMWare users where desktop resizing was no longer working. There was a patch available but it did not work for me, so I worked with Thomas Hellstrom (of VMWare) to identify the problems and he provided me an updated patch. I submitted this patch to Debian too (bug report, pull request).

Linux 4.12 also showed another regression for VMWare users where the screen would not be refreshed/updated when you are using Wayland/KMS. I did multiple tests for Thomas and provided the requested data so that they could create a fix (which I incorporated into Kali and should come to Debian through the upstream stable tree).

Packaging. I uploaded zim 0.67 to unstable. I fixed an RC bug on shiboken to get pyside and ubertooth back into testing. I had to hack the package to use gcc-6 on mips64el because that architecture is suffering from a severe gcc bug which probably broke a large part of the code compiled since the switch to gcc-7 (and which triggered a test failure in shiboken, fortunately)… I wonder if anybody will make sure to recompile all packages that might have been misbuilt.

Infrastructure. In a discussion on debian-devel, the topic of using tracker.debian.org to store “who is maintaining what” came up again. I responded to let know that this is something that I’d like to see done and that I have already taken measures to go into this direction. I wanted to make an experiment with my zim package but quickly came on a problem with ftpmaster’s lintian auto-rejects (which I submitted in #871575).

The BTS is now linking to tracker.debian.org on its web interface. To continue and give a push to this move, I scanned all the files in the qa SVN repository and updated many occurrences of packages.qa.debian.org with tracker.debian.org.

I also spotted a small problem in the way we handle autoremovals mails in tracker.debian.org, we often get them twice: I filed #871683 to get this fixed on release.debian.org.

Bug reports. vmdebootstrap creates unbootable qemu image (#872999). bugs in udebs are not shown on view by source package (#872784). New upstream release of ethtool (#873692). Upstream bugreport on systemd: support a systemd.swap=no boot command-line option.

I also shared some of my ideas/dreams in #859867 speaking of a helper tool to setup and maintain up-to-date build chroots and autopkgtest qemu images.

More bug fixes and pull requests. I created a patch to fix a build failure of systemd when /tmp is an overlayfs (#854400, the pull request has been discarded). I fixed the RC bug #853570 on ncrack and forwarded my changes upstream (here and here).

Thanks

See you next month for a new summary of my activities.

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Raphaël Hertzog https://raphaelhertzog.com apt-get install debian-wizard

Review: Regeneration

Pre, 01/09/2017 - 7:30pd

Review: Regeneration, by Julie E. Czerneda

Series: Species Imperative #3 Publisher: DAW Copyright: 2006 ISBN: 0-7564-0345-6 Format: Hardcover Pages: 543

This is the third book of the Species Imperative trilogy, and this is the type of trilogy that's telling a single story in three books. You don't want to read this out of order, and I'll have to be cautious about aspects of the plot to not spoil the earlier books.

Mac is still recovering from the effects of the first two books of the series, but she's primarily worried about a deeply injured friend. Worse, that friend is struggling to explain or process what's happened, and the gaps in her memory and her very ability to explain may point at frightening, lingering risks to humanity. As much as she wants to, Mac can't give her friend all of her focus, since she's also integral to the team trying to understand the broader implications of the events of Migration. Worse, some of the non-human species have their own contrary interpretations that, if acted on, Mac believes would be desperately risky for humanity and all the other species reachable through the transects.

That set of competing priorities and motivations eventually sort themselves out into a tense and rewarding multi-species story, but they get off to an awkward start. The first 150 pages of Regeneration are long on worry, uncertainty, dread, and cryptic conversations, and short on enjoyable reading. Czerneda's recaps of the previous books are appreciated, but they weren't very smoothly integrated into the story. (I renew my occasional request for series authors to include a simple plot summary of the previous books as a prefix, without trying to weave it into the fiction.) I was looking forward to this book after the excellent previous volumes, but struggled to get into the story.

That does change. It takes a bit too long, with a bit too much nameless dread, a bit too much of an irritating subplot between Fourteen and Oversight that I didn't think added anything to the book, and not enough of Mac barreling forward doing sensible things. But once Mac gets back into space, with a destination and a job and a collection of suspicious (or arrogant) humans and almost-incomprehensible aliens to juggle, Czerneda hits her stride.

Czerneda doesn't entirely avoid Planet of the Hats problems with her aliens, but I think she does better than most of science fiction. Alien species in this series do tend to be a bit all of a type, and Mac does figure them out by drawing conclusions from biology, but those conclusions are unobvious and based on Mac's mix of biological and human social intuition. They refreshingly aren't as simple as biology completely shaping culture. (Czerneda's touch is more subtle than James White's Sector General, for example.) And Mac has a practical, determined, and selfless approach that's deeply likable and admirable. It's fun as a reader to watch her win people over by just being competent, thoughtful, observant, and unrelentingly ethical.

But the best part of this book, by far, are the Sinzi.

They first appeared in the second book, Migration, and seemed to follow the common SF trope of a wise elder alien race that can bring some order to the universe and that humanity can learn from. They, or more precisely the one Sinzi who appeared in Migration, was very good at that role. But Czerneda had something far more interesting planned, and in Regeneration they become truly alien in their own right, with their own nearly incomprehensible way of viewing the universe.

There are so many ways that this twist can go wrong, and Czerneda avoids all of them. She doesn't undermine their gravitas, nor does she elevate them to the level of Arisians or other semi-angelic wise mentors of other series. Czerneda makes them different in profound ways that are both advantage and disadvantage, pulls that difference into the plot as a complicating element, and has Mac stumble yet again into a role that is accidentally far more influential than she intends. Mac is the perfect character to do that to: she has just the right mix of embarrassment, ethics, seat-of-the-pants blunt negotiation skills, and a strong moral compass. Given a lever and a place to stand, one can believe that Mac can move the world, and the Sinzi are an absolutely fascinating lever.

There are also three separate, highly differentiated Sinzi in this story, with different goals, life experience, personalities, and levels of gravitas. Czerneda's aliens are good in general, but her focus is usually more on biology than individual differentiation. The Sinzi here combine the best of both types of character building.

I think the ending of Regeneration didn't entirely work. After all the intense effort the characters put into understanding the complexity of the universe over the course of the series, the denouement has a mopping-up feel and a moral clarity that felt a bit too easy. But the climax has everything I was hoping for, there's a lot more of Mac being Mac, and I loved every moment of the Sinzi twist. Now I want a whole new series exploring the implications of the Sinzi's view of the universe on the whole history of galactic politics that sat underneath this story. But I'll settle for moments of revelation that sent shivers down my spine.

This is a bit of an uneven book that falls short of its potential, but I'll remember it for a long time. Add it on to a deeply rewarding series, and I will recommend the whole package unreservedly. The Species Imperative is excellent science fiction that should be better-known than it is. I still think the romance subplot was unfortunate, and occasionally the aliens get too cartoony (Fourteen, in particular, goes a bit too far in that direction), but Czerneda never lingers too long on those elements. And the whole work is some of the best writing about working scientific research and small-group politics that I've read.

Highly recommended, but read the whole series in order.

Rating: 9 out of 10

Russ Allbery https://www.eyrie.org/~eagle/ Eagle's Path

RcppAnnoy 0.0.9

Pre, 01/09/2017 - 3:20pd

An new version 0.0.9 of RcppAnnoy, our Rcpp-based R integration of the nifty Annoy library by Erik, is now on CRAN. Annoy is a small and lightweight C++ template header library for very fast approximate nearest neighbours.

This release corrects an issue for Windows users discovered by GitHub user 'khoran' who later also suggested the fix of binary mode. It upgrades to Annoy release 1.9.1 and brings its new Manhattan distance to RcppAnnoy. A number of unit tests were added as well, and we updated some packaging internals such as symbol registration.

And I presume I had a good streak emailing with Uwe's robots as the package made it onto CRAN rather smoothly within ten minutes of submission:

 

Changes in this version are summarized here:

Changes in version 0.0.9 (2017-08-31)
  • Synchronized with Annoy upstream version 1.9.1

  • Minor updates in calls and tests as required by annoy 1.9.1

  • New Manhattan distance modules along with unit test code

  • Additional unit tests from upstream test code carried over

  • Binary mode is used for save (as suggested by @khoran in #21)

  • A new file init.c was added with calls to R_registerRoutines() and R_useDynamicSymbols()

  • Symbol registration is enabled in useDynLib

Courtesy of CRANberries, there is also a diffstat report for this release.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

Dirk Eddelbuettel http://dirk.eddelbuettel.com/blog Thinking inside the box

FLOSS Activities August 2017

Pre, 01/09/2017 - 1:45pd
Changes Issues Review Administration
  • myrepos: get commit/admin access from joeyh at DebConf17, add commit/admin access for other patch submitters, apply my stack of patches
  • Debian: fix weird log file issues, redirect hardware donor, cleaned up a weird dir, fix some OOB info, ask for TLS on meetings-archive.d.n, check an I/O error, restart broken stunnels, powercycle 1 borked machine,
  • Debian mentors: lintian/security updates & reboot
  • Debian wiki: remove some stray cache files, whitelist 3 email domains, whitelist some email addresses, disable 1 spammer account, disable 1 accounts with bouncing email,
  • Debian QA: apply patch to fix PTS watch file errors, deploy changes
  • Debian derivatives census: run scripts for Purism, remove some noise from logs, trigger a recheck, merge fix by Unit193, deploy changes
  • Openmoko: security updates, reboots, enable unattended-upgrades
Communication
  • Attended DebConf17 and provided some input in BoFs
  • Sent Misc Dev News #44
  • Invite Google gLinux (on IRC) to the Debian derivatives census
  • Welcome Sven Haardiek (of GreenboneOS) to the Debian derivatives census
  • Inquire about the status of Canaima
Sponsors

The samba bug report was sponsored by my employer. All other work was done on a volunteer basis.

Paul Wise http://bonedaddy.net/pabs3/log/ Log

Free software activities in August 2017

Enj, 31/08/2017 - 10:39md

Here is my monthly update covering what I have been doing in the free software world in August 2017 (previous month):

  • Created ZeroCoolOS, a live operating system that plays the film Hackers (1995) on a continuous loop.
  • Sent a patch for pristine-tar to allow storage of detached upstream signatures. (#871809)
  • Worked more on Lintian, a static analysis tool for Debian packages, reporting on various errors, omissions and quality-assurance issues to the maintainer (previous changes):
    • Fix an apache2-unparsable-dependency false positive by allowing periods in dependency names. (#873701)
    • Ignore "repacked" packages when checking for upstream source tarball signatures as they will never match.
    • Downgrade the severity of orig-tarball-missing-upstream-signature. (#870722)
    • From a suggestion by Theodore Ts'o, expand the explanation of orig-tarball-missing-upstream-signature to include the location of where dpkg-source looks.
    • Address a number of issues in the copyright-year-in-future tag including preventing false positives in port numbers, email addresses, ISO standard numbers and street addresses (#869788), as well as "meta" or testing statements (#873323). In addition, report all violating years in a line and expand the testsuite.
    • Don't match quoted "FIXME" variants of file-contains-fixme-placeholder (#870199), avoid checking copyright_hints files (#872843) and downgrade the tag's severity.
    • Apply a patch from Alex Muntada to recommend "substr" over of "substring" in mentions-deprecated-usr-lib-perl5-directory. (#871767)
    • Prevent missing-build-dependency-for-dh_-command false positives exposed by following the advice in useless-autoreconf-build-depends. (#869541)
    • Ensure readme-debian-contains-debmake-template also checks for files containing "Automatically generated by debmake".
    • Check python3-foo packages have a Section: python, not just python2-foo. (#870272)
    • Check for packages shipping compiled Java class files. (#873211)
    • Additionally consider .cljc files to avoid codeless-jar warnings. (#870649)
    • Prevent desktop-entry-lacks-keywords-entry false positives for Link and Directory-style .desktop files. (#873702)
    • Split out Python checks from checks/scripts.pm check to a new, source check of type source.
    • Check for python-foo without a corresponding python3-foo package. (#870681)
    • Complain about packages that Build-Depend on python-sphinx only. (#870730)
    • Warn about packages that alternatively Build-Depend on the Python 2 and Python 3 versions of Sphinx. (#870758)
    • Check for packages that depend on Python 2.x. (#870822)
    • Correct false positives in unconditional-use-of-dpkg-statoverride by detecting "if !" as a shell prefix. (#869587)
    • Alert on for missing calls to dpkg-maintscript-helper(1) in maintainer scripts. (#872042)
    • Check for packages using sensible-utils without declaring a dependency after splitting from debianutils. (#872611)
    • Warn about scripts using nodejs as an interpreter now that the nodejs script provides /usr/bin/node. (#873096)
    • Remove recommendations to add a Testsuite: autopkgtest field to debian/control and emit a new tag the package if it does so. (#865531)
    • Recognise autopkgtest-pkg-elpa as a valid test suite. (#873458)
    • Add note to /etc/bash_completion.d's obsolete path warning output regarding stricter filename requirements. (#814599)
    • Add 4.0.1 and 4.1.0 as known Policy standards versions.
    • Apply a patch from Maia Everett to avoid British spellings under the en_US locale. (#868897)
    • Stop emitting {maintainer,uploader}-address-causes-mail-loops for @packages.debian.org addresses. (#871575)
    • Modify Lintian::Data's all subroutine to always return keys in insertion order.
    • Apply a patch from Steve Langasek to accomodate binutils outputting symbols in a different format on the ppc64el architecture. (#869750)
    • Add an explicit test for packages including external fonts via the Google Font and TypeKit APIs. (#873434)
    • Add missing entries in internal Test-For fields to make development/testing workflow less error-prone.
  • Sent three pull requests to git-buildpackage, a tool to assist in Debian packaging from Git repositories:
    • Make pq --abbrev= configurable. (#872351)
    • Use build profiles to avoid installation of test dependencies. (#31)
    • Correct "allow to" grammar. (#30)
  • Updated travis.debian.net (my hosted service for projects that host their Debian packaging on GitHub to use the Travis CI continuous integration platform for testing):
    • Move away from deb.debian.org; Travis appears to be using a HTTP proxy that strips SRV records. (commit)
    • Highlight double quotes are required for TRAVIS_DEBIAN_EXTRA_REPOSITORY. (commit)
    • Use force-unsafe-io. (commit)
    • Clarify docs when upstream already has a travis.yml file. (#46)
    • Make documentation easier to copy-paste. (commit)
  • Merged a pull request in django-slack, my library to easily post messages to the Slack group-messaging utility, where instantiation of a SlackException was failing. (#71)
  • Assigned two pull requests to the Redis key-value database store to correct "did not received" and "faield" typos. (#4216 & #4215).
Reproducible builds

Whilst anyone can inspect the source code of free software for malicious flaws, most software is distributed pre-compiled to end users.

The motivation behind the Reproducible Builds effort is to allow verification that no flaws have been introduced — either maliciously or accidentally — during this compilation process by promising identical results are always generated from a given source, thus allowing multiple third-parties to come to a consensus on whether a build was compromised.

I have generously been awarded a grant from the Core Infrastructure Initiative to fund my work in this area.

This month I:

  • Presented a status update at Debconf17 in Montréal, Canada alongside Holger Levsen, Maria Glukhova, Steven Chamberlain, Vagrant Cascadian, Valerie Young and Ximin Luo.
  • I worked on the following issues upstream:
    • glib2.0: Please make the output of gio-querymodules reproducible. (...)
    • gcab: Please make the output reproducible. (...)
    • gtk+2.0: Please make the immodules.cache files reproducible. (...)
    • desktop-file-utils: Please make the output reproducible. (...)
  • Within Debian:
  • Categorised a large number of packages and issues in the Reproducible Builds "notes" repository.
  • Worked on publishing our weekly reports. (#118, #119, #120, #121 & #122)

I also made the following changes to our tooling:

diffoscope

diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues.

  • Use name attribute over path to avoid leaking comparison full path in output. (commit)
  • Add missing skip_unless_module_exists import. (commit)
  • Tidy diffoscope.progress and the XML comparator (commit, commit)

disorderfs

disorderfs is our FUSE-based filesystem that deliberately introduces non-determinism into directory system calls in order to flush out reproducibility issues.

  • Add a simple autopkgtest smoke test. (commit)


Debian Patches contributed
  • openssh: Quote the IP address in ssh-keygen -f suggestions. (#872643)
  • libgfshare:
    • SIGSEGV if /dev/urandom is not accessible. (#873047)
    • Add bindnow hardening. (#872740)
    • Support nodoc build profile. (#872739)
  • devscripts:
  • memcached: Add hardening to systemd .service file. (#871610)
  • googler: Tidy long and short package descriptions. (#872461)
  • gnome-split: Homepage points to domain-parked website. (#873037)
Uploads
  • python-django 1:1.11.4-1 — New upstream release.
  • redis:
    • 4:4.0.1-3 — Drop yet more non-deterministic tests.
    • 4:4.0.1-4 — Tighten systemd/seccomp hardening.
    • 4:4.0.1-5 — Drop even more tests with timing issues.
    • 4:4.0.1-6 — Don't install completions to /usr/share/bash-completion/completions/debian/bash_completion/.
    • 4:4.0.1-7 — Don't let sentinel integration tests fail the build as they use too many timers to be meaningful. (#872075)
  • python-gflags 1.5.1-3 — If SOURCE_DATE_EPOCH is set, either use that as a source of current dates or the UTC-version of the file's modification time (#836004), don't call update-alternatives --remove in postrm. update debian/watch/Homepage & refresh/tidy the packaging.
  • bfs 1.1.1-1 — New upstream release, tidy autopkgtest & patches, organising the latter with Pq-Topic.
  • python-daiquiri 1.2.2-1 — New upstream release, tidy autopkgtests & update travis.yml from travis.debian.net.
  • aptfs 2:0.10-2 — Add upstream signing key, refer to /usr/share/common-licenses/GPL-3 in debian/copyright & tidy autopkgtests.
  • adminer 4.3.1-2 — Add a simple autopkgtest & don't install the Selenium-based tests in the binary package.
  • zoneminder (1.30.4+dfsg-2) — Prevent build failures with GCC 7 (#853717) & correct example /etc/fstab entries in README.Debian (#858673).

Finally, I reviewed and sponsored uploads of astral, inflection, more-itertools, trollius-redis & wolfssl.

Debian LTS

This month I have been paid to work 18 hours on Debian Long Term Support (LTS). In that time I did the following:

  • "Frontdesk" duties, triaging CVEs, etc.
  • Issued DLA 1049-1 for libsndfile preventing a remote denial of service attack.
  • Issued DLA 1052-1 against subversion to correct an arbitrary code execution vulnerability.
  • Issued DLA 1054-1 for the libgxps XML Paper Specification library to prevent a remote denial of service attack.
  • Issued DLA 1056-1 for cvs to prevent a command injection vulnerability.
  • Issued DLA 1059-1 for the strongswan VPN software to close a denial of service attack.
Debian bugs filed
  • wget: Please hash the hostname in ~/.wget-hsts files. (#870813)
  • debian-policy: Clarify whether mailing lists in Maintainers/Uploaders may be moderated. (#871534)
  • git-buildpackage: "pq export" discards text within square brackets. (#872354)
  • qa.debian.org: Escape HTML in debcheck before outputting. (#872646)
  • pristine-tar: Enable multithreaded compression in pristine-xz. (#873229)
  • tryton-meta: Please combine tryton-modules-* into a single source package with multiple binaries. (#873042)
  • azure-cli:
  • fwupd-tests: Don't ship test files to generic /usr/share/installed-tests dir. (#872458)
  • libvorbis: Maintainer fields points to a moderated mailing list. (#871258)
  • rmlint-gui: Ship a rmlint-gui binary. (#872162)
  • template-glib: debian/copyright references online source without quotation. (#873619)
FTP Team

As a Debian FTP assistant I ACCEPTed 147 packages: abiword, adacgi, adasockets, ahven, animal-sniffer, astral, astroidmail, at-at-clojure, audacious, backdoor-factory, bdfproxy, binutils, blag-fortune, bluez-qt, cheshire-clojure, core-match-clojure, core-memoize-clojure, cypari2, data-priority-map-clojure, debian-edu, debian-multimedia, deepin-gettext-tools, dehydrated-hook-ddns-tsig, diceware, dtksettings, emacs-ivy, farbfeld, gcc-7-cross-ports, git-lfs, glewlwyd, gnome-recipes, gnome-shell-extension-tilix-dropdown, gnupg2, golang-github-aliyun-aliyun-oss-go-sdk, golang-github-approvals-go-approval-tests, golang-github-cheekybits-is, golang-github-chzyer-readline, golang-github-denverdino-aliyungo, golang-github-glendc-gopher-json, golang-github-gophercloud-gophercloud, golang-github-hashicorp-go-rootcerts, golang-github-matryer-try, golang-github-opentracing-contrib-go-stdlib, golang-github-opentracing-opentracing-go, golang-github-tdewolff-buffer, golang-github-tdewolff-minify, golang-github-tdewolff-parse, golang-github-tdewolff-strconv, golang-github-tdewolff-test, golang-gopkg-go-playground-validator.v8, gprbuild, gsl, gtts, hunspell-dz, hyperlink, importmagic, inflection, insighttoolkit4, isa-support, jaraco.itertools, java-classpath-clojure, java-jmx-clojure, jellyfish1, lazymap-clojure, libblockdev, libbytesize, libconfig-zomg-perl, libdazzle, libglvnd, libjs-emojify, libjwt, libmysofa, libundead, linux, lua-mode, math-combinatorics-clojure, math-numeric-tower-clojure, mediagoblin, medley-clojure, more-itertools, mozjs52, openssh-ssh1, org-mode, oysttyer, pcscada, pgsphere, poppler, puppetdb, py3status, pycryptodome, pysha3, python-cliapp, python-coloredlogs, python-consul, python-deprecation, python-django-celery-results, python-dropbox, python-fswrap, python-hbmqtt, python-intbitset, python-meshio, python-parameterized, python-pgpy, python-py-zipkin, python-pymeasure, python-thriftpy, python-tinyrpc, python-udatetime, python-wither, python-xapp, pythonqt, r-cran-bit, r-cran-bit64, r-cran-blob, r-cran-lmertest, r-cran-quantmod, r-cran-ttr, racket-mode, restorecond, rss-bridge, ruby-declarative, ruby-declarative-option, ruby-errbase, ruby-google-api-client, ruby-rash-alt, ruby-representable, ruby-test-xml, ruby-uber, sambamba, semodule-utils, shimdandy, sjacket-clojure, soapysdr, stencil-clojure, swath, template-glib, tools-analyzer-jvm-clojure, tools-namespace-clojure, uim, util-linux, vim-airline, vim-airline-themes, volume-key, wget2, xchat, xfce4-eyes-plugin & xorg-gtest.

I additionally filed 6 RC bugs against packages that had incomplete debian/copyright files against: gnome-recipes, golang-1.9, libdazzle, poppler, python-py-zipkin & template-glib.

Chris Lamb https://chris-lamb.co.uk/blog/category/planet-debian lamby: Items or syndication on Planet Debian.

C, floating point, and help!

Enj, 31/08/2017 - 6:58md

Floating point is a pain. I know this. But I recently took over the sigrok packages in Debian and as part of updating to the latest libsigkrok4 library enabled the post compilation tests. Which promptly failed on i386. Some narrowing down of the problem leads to the following test case (which fails on both gcc-6 under Debian/Stretch and gcc-7 on Debian/Testing):

#include <inttypes.h> #include <stdio.h> #include <stdint.h> int main(int argc, char *argv[]) { printf("%" PRIu64 "\n", (uint64_t)((1.034567) * (uint64_t)(1000000ULL))); }

We expect to see 1.034567 printed out. On x86_64 we do:

$ arch x86_64 $ gcc -Wall t.c -o t ; ./t 1034567

If we compile for 32-bit the result is also as expected:

$ gcc -Wall -m32 t.c -o t ; ./t 1034567

Where things get interesting is when we enable --std=c99:

$ gcc -Wall --std=c99 t.c -o t ; ./t 1034567 $ gcc -Wall -m32 --std=c99 t.c -o t ; ./t 1034566

What? It turns out all the cXX standards result in the last digit incorrectly being 6, while the gnuXX standards (gnu11 is apparently the default) result in the correct trailing 7. Is there some postfix I can add to the value to prevent the floating point truncation taking place? Or do I just have to accept this? It works fine on armel, so it’s not a simple 32/64 bit issue.

Jonathan McDowell https://www.earth.li/~noodles/blog/ Noodles' Emptiness

gwolf.blog.fork()

Enj, 31/08/2017 - 6:21md

Ohai,

I have recently started to serve as a Feature Editor for the ACM XRDS magazine. As such, I was also invited to post some general blog posts on XRDS blog — And I just started yesterday by posting about DebConf.

I'm not going to pull (or mention) each of my posts in my main blog, nor will I syndicate it to Planet Debian (where most of my readership comes from), although I did add it to my dlvr.it account (that relays my posts to Twitter and Facebook, for those of you that care about said services). This mention is a one-off thing.

So, if you want to see yet another post explaining what is DebConf and what is Debian to the wider public, well... That's what I came up with :)

gwolf http://gwolf.org Gunnar Wolf

gwolf.blog.fork()

Enj, 31/08/2017 - 5:54md

Ohai,

I have recently started to serve as a Feature Editor for the ACM XRDS magazine. As such, I was also invited to post some general blog posts on XRDS blog — And I just started yesterday by posting about DebConf.

I'm not going to pull (or mention) each of my posts in my main blog, nor will I syndicate it to Planet Debian (where most of my readership comes from), although I did add it to my dlvr.it account (that relays my posts to Twitter and Facebook, for those of you that care about said services). This mention is a one-off thing.

So, if you want to see yet another post explaining what is DebConf and what is Debian to the wider public, well... Thate's what I came up with :)

[Update]: Of course, I wanted to thank Aigars Mahinovs for the photos I used on that post. Have you looked at them all? I spent a moste enjoyable time going through them :-]

gwolf http://gwolf.org Gunnar Wolf

Firefox slow as HEL even after boosting RAM from 4GB to 16GB

Enj, 31/08/2017 - 12:33md
The title says it all: Firefox is the only piece of software that shows zero sign of improvement in its performance after quadrupling the amount of RAM installed on my 64-bit desktop computer. All other applications show a significant boost in performance. Yet, among all the applications I use, Firefox is the one that most needed this speed boost. To say that this is a major disapointment is an understatement. FFS, Mozilla devs! Martin-Éric noreply@blogger.com Funkyware: ITCetera

GRUB and LUKS

Mër, 30/08/2017 - 7:27md

I got myself stuck yesterday with GRUB running from an ext4 /boot/grub, but with /boot inside my LUKS LVM root partition, which meant GRUB couldn’t load the initramfs and kernel.

Luckily, it turns out that GRUB does know how to mount LUKS volumes (and LVM volumes), but all the instructions I could find talk about setting this up ahead of time (“Add GRUB_ENABLE_CRYPTODISK=y to /etc/default/grub“), rather than what the correct manual GRUB commands are to get things running on a failed boot.

These are my notes on that, in case I ever need to do this again, since there was one specific gotcha with using GRUB’s cryptomount command (noted below).

Available devices were the raw disk (hd0), the /boot/grub partition (hd0,msdos1), and the LUKS volume (hd0,msdos5):

grub> ls (hd0) (hd0,msdos1) (hd0,msdos5)

Used cryptomount to open the LUKS volume (but without ()s! It says it works if you use parens, but then you can’t use the resulting (crypto0)):

grub> insmod luks grub> cryptomount hd0,msdos5 Enter password... Slot 0 opened.

Then you can load LVM and it’ll see inside the LUKS volume:

grub> insmod lvm grub> ls (crypto0) (hd0) (hd0,msdos1) (hd0,msdos5) (lvm/rootvg-rootlv)

And then I could boot normally:

grub> configfile $prefix/grub.cfg

After booting, I added GRUB_ENABLE_CRYPTODISK=y to /etc/default/grub and ran update-grub. I could boot normally after that, though I’d be prompted twice for the LUKS passphrase (once by GRUB, then again by the initramfs).

To avoid this, it’s possible to add a second LUKS passphrase, contained in a file in the initramfs, as described here and works for Ubuntu and Debian too. The quick summary is:

Create the keyfile and add it to LUKS:

# dd bs=512 count=4 if=/dev/urandom of=/crypto_keyfile.bin # chmod 0400 /crypto_keyfile.bin # cryptsetup luksAddKey /dev/sda5 /crypto_keyfile.bin *enter original password*

Adjust the /etc/crypttab to include passing the file via /bin/cat:

sda5_crypt UUID=4aa5da72-8da6-11e7-8ac9-001cc008534d /crypto_keyfile.bin luks,keyscript=/bin/cat

Add an initramfs hook to copy the key file into the initramfs, keep non-root users from being able to read your initramfs, and trigger a rebuild:

# cat > /etc/initramfs-tools/hooks/crypto_keyfile <<EOF #!/bin/bash if [ "$1" = "prereqs" ] ; then cp /crypto_keyfile.bin "${DESTDIR}" fi EOF # chmod a+x /etc/initramfs-tools/hooks/crypto_keyfile # chmod 0700 /boot # update-initramfs -u

This has the downside of leaving a LUKS passphrase “in the clear” while you’re booted, but if someone has root, they can just get your dm-crypt encryption key directly anyway:

# dmsetup table --showkeys sda5_crypt 0 155797496 crypt aes-cbc-essiv:sha256 e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 0 8:5 2056

And of course if you’re worried about Evil Maid attacks, you’ll need a real static root of trust instead of doing full disk encryption passphrase prompting from an unverified /boot partition. :)

© 2017, Kees Cook. This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 License.

kees https://outflux.net/blog Debian – codeblog

STM32 USB and Rust - Packet Memory Area

Mër, 30/08/2017 - 6:15md

In this, our next exciting installment of STM32 and Rust for USB device drivers, we're going to look at what the STM32 calls the 'packet memory area'. If you've been reading along with the course, including reading up on the datasheet content then you'll be aware that as well as the STM32's normal SRAM, there's a 512 byte SRAM dedicated to the USB peripheral. This SRAM is called the 'packet memory area' and is shared between the main bus and the USB peripheral core. Its purpose is, simply, to store packets in transit. Both those IN to the host (so stored queued for transmission) or OUT from the host (so stored, queued for the application to extract and consume).

It's time to actually put hand to keyboard on some Rust code, and the PMA is the perfect starting point, since it involves two basic structures. Packets are the obvious first structure, and they are contiguous sets of bytes which for the purpose of our work we shall assume are one to sixty-four bytes long. The second is what the STM32 datasheet refers to as the BTABLE or Buffer Descriptor Table. Let's consider the BTABLE first.

The Buffer Descriptor Table

The BTABLE is arranged in quads of 16bit words. For "normal" endpoints this is a pair of descriptors, each consisting of two words, one for transmission, and one for reception. The STM32 also has a concept of double buffered endpoints, but we're not going to consider those in our proof-of-concept work. The STM32 allows for up to eight endpoints (EP0 through EP7) in internal register naming, though they support endpoints numbered from zero to fifteen in the sense of the endpoint address numbering. As such there're eight descriptors each four 16bit words long (eight bytes) making for a buffer descriptor table which is 64 bytes in size at most.

Buffer Descriptor Table Byte offset in PMA Field name Description (EPn * 8) + 0 USB_ADDRn_TX The address (inside the PMA) of the TX buffer for EPn (EPn * 8) + 2 USB_COUNTn_TX The number of bytes present in the TX buffer for EPn (EPn * 8) + 4 USB_ADDRn_RX The address (inside the PMA) of the RX buffer for EPn (EPn * 8) + 6 USB_COUNTn_RX The number of bytes of space available for the RX buffer for EPn (and once received, the number of bytes received)

The TX entries are trivial to comprehend. To transmit a packet, part of the process involves writing the packet into the PMA, putting the address into the appropriate USB_ADDRn_TX entry, and the length into the corresponding USB_COUNTn_TX entry, before marking the endpoint as ready to transmit.

To receive a packet though is slightly more complex. The application must allocate some space in the PMA, setting the address into the USB_ADDRn_RX entry of the BTABLE before filling out the top half of the USB_COUNTn_RX entry. For ease of bit sizing, the STM32 only supports space allocations of two to sixty-two bytes in steps of two bytes at a time, or thirty-two to five-hundred-twelve bytes in steps of thirty-two bytes at a time. Once the packet is received, the USB peripheral will fill out the lower bits of the USB_COUNTn_RX entry with the actual number of bytes filled out in the buffer.

Packets themselves

Since packets are, typically, a maximum of 64 bytes long (for USB 2.0) and are simply sequences of bytes with no useful structure to them (as far as the USB peripheral itself is concerned) the PMA simply requires that they be present and contiguous in PMA memory space. Addresses of packets are relative to the base of the PMA and are byte-addressed, however they cannot start on an odd byte, so essentially they are 16bit addressed. Since the BTABLE can be anywhere within the PMA, as can the packets, the application will have to do some memory management (either statically, or dynamically) to manage the packets in the PMA.

Accessing the PMA

The PMA is accessed in 16bit word sections. It's not possible to access single bytes of the PMA, nor is it conveniently structured as far as the CPU is concerned. Instead the PMA's 16bit words are spread on 32bit word boundaries as far as the CPU knows. This is done for convenience and simplicity of hardware, but it means that we need to ensure our library code knows how to deal with this.

First up, to convert an address in the PMA into something which the CPU can use we need to know where in the CPU's address space the PMA is. Fortunately this is fixed at 0x4000_6000. Secondly we need to know what address in the PMA we wish to access, so we can determine which 16bit word that is, and thus what the address is as far as the CPU is concerned. If we assume we only ever want to access 16bit entries, we can just multiply the PMA offset by two before adding it to the PMA base address. So, to access the 16bit word at byte-offset 8 in the PMA, we'd look for the 16bit word at 0x4000_6000 + (0x08 * 2) => 0x4000_6010.

Bundling the PMA into something we can use

I said we'd do some Rust, and so we shall…

// Thanks to the work by Jorge Aparicio, we have a convenient wrapper // for peripherals which means we can declare a PMA peripheral: pub const PMA: Peripheral<PMA> = unsafe { Peripheral::new(0x4000_6000) }; // The PMA struct type which the peripheral will return a ref to pub struct PMA { pma_area: PMA_Area, } // And the way we turn that ref into something we can put a useful impl on impl Deref for PMA { type Target = PMA_Area; fn deref(&self) -> &PMA_Area { &self.pma_area } } // This is the actual representation of the peripheral, we use the C repr // in order to ensure it ends up packed nicely together #[repr(C)] pub struct PMA_Area { // The PMA consists of 256 u16 words separated by u16 gaps, so lets // represent that as 512 u16 words which we'll only use every other of. words: [VolatileCell<u16>; 512], }

That block of code gives us three important things. Firstly a peripheral object which we will be able to (later) manage nicely as part of the set of peripherals which RTFM will look after for us. Secondly we get a convenient packed array of u16s which will be considered volatile (the compiler won't optimise around the ordering of writes etc). Finally we get a struct on which we can hang an implementation to give our PMA more complex functionality.

A useful first pair of functions would be to simply let us get and put u16s in and out of that word array, since we're only using every other word…

impl PMA_Area { pub fn get_u16(&self, offset: usize) -> u16 { assert!((offset & 0x01) == 0); self.words[offset].get() } pub fn set_u16(&self, offset: usize, val: u16) { assert!((offset & 0x01) == 0); self.words[offset].set(val); } }

These two functions take an offset in the PMA and return the u16 word at that offset. They only work on u16 boundaries and as such they assert that the bottom bit of the offset is unset. In a release build, that will go away, but during debugging this might be essential. Since we're only using 16bit boundaries, this means that the first word in the PMA will be at offset zero, and the second at offset two, then four, then six, etc. Since we allocated our words array to expect to use every other entry, this automatically converts into the addresses we desire.

If we pop (and please don't worry about the unsafe{} stuff for now):

unsafe { (&*usb::pma::PMA.get()).set_u16(4, 64); }

into our main function somewhere, and then build and objdump our test binary we can see the following set of instructions added:

80001e4: f246 0008 movw r0, #24584 ; 0x6008 80001e8: 2140 movs r1, #64 ; 0x40 80001ea: f2c4 0000 movt r0, #16384 ; 0x4000 80001ee: 8001 strh r1, [r0, #0]

This boils down to a u16 write of 0x0040 (64) to the address 0x4006008 which is the third 32 bit word in the CPU's view of the PMA memory space (where offset 4 is the third 16bit word) which is exactly what we'd expect to see.

We can, from here, build up some functions for manipulating a BTABLE, though the most useful ones for us to take a look at are the RX counter functions:

pub fn get_rxcount(&self, ep: usize) -> u16 { self.get_u16(BTABLE + (ep * 8) + 6) & 0x3ff } pub fn set_rxcount(&self, ep: usize, val: u16) { assert!(val <= 1024); let rval: u16 = { if val > 62 { assert!((val & 0x1f) == 0); (((val >> 5) - 1) << 10) | 0x8000 } else { assert!((val & 1) == 0); (val >> 1) << 10 } }; self.set_u16(BTABLE + (ep * 8) + 6, rval) }

The getter is fairly clean and clear, we need the BTABLE base in the PMA, add the address of the USB_COUNTn_RX entry to that, retrieve the u16 and then mask off the bottom ten bits since that's the size of the relevant field.

The setter is a little more complex, since it has to deal with the two possible cases, this isn't pretty and we might be able to write some better peripheral structs in the future, but for now, if the length we're setting is 62 or less, and is divisible by two, then we put a zero in the top bit, and the number of 2-byte lumps in at bits 14:10, and if it's 64 or more, we mask off the bottom to check it's divisible by 32, and then put the count (minus one) of those blocks in, instead, and set the top bit to mark it as such.

Fortunately, when we set constants, Rust's compiler manages to optimise all this very quickly. For a BTABLE at the bottom of the PMA, and an initialisation statement of:

unsafe { (&*usb::pma::PMA.get()).set_rxcount(1, 64); }

then we end up with the simple instruction sequence:

80001e4: f246 001c movw r0, #24604 ; 0x601c 80001e8: f44f 4104 mov.w r1, #33792 ; 0x8400 80001ec: f2c4 0000 movt r0, #16384 ; 0x4000 80001f0: 8001 strh r1, [r0, #0]

We can decompose that into a C like *((u16*)0x4000601c) = 0x8400 and from there we can see that it's writing to the u16 at 0x1c bytes into the CPU's view of the PMA, which is 14 bytes into the PMA itself. Since we know we set the BTABLE at the start of the PMA, it's 14 bytes into the BTABLE which is firmly in the EP1 entries. Specifically it's USB_COUNT1_RX which is what we were hoping for. To confirm this, check out page 651 of the datasheet. The value set was 0x8400 which we can decompose into 0x8000 and 0x0400. The first is the top bit and tells us that BL_SIZE is one, and thus the blocks are 32 bytes long. Next the 0x4000 if we shift it right ten places, we get the value 2 for the field NUM_BLOCK and multiplying 2 by 32 we get the 64 bytes we asked it to set as the size of the RX buffer. It has done exactly what we hoped it would, but the compiler managed to optimise it into a single 16 bit store of a constant value to a constant location. Nice and efficient.

Finally, let's look at what happens if we want to write a packet into the PMA. For now, let's assume packets come as slices of u16s because that'll make our life a little simpler:

pub fn write_buffer(&self, base: usize, buf: &[u16]) { for (ofs, v) in buf.iter().enumerate() { self.set_u16(base + (ofs * 2), *v); } }

Yes, even though we're deep in no_std territory, we can still get an iterator over the slice, and enumerate it, getting a nice iterator of (index, value) though in this case, the value is a ref to the content of the slice, so we end up with *v to deref it. I am sure I could get that automatically happening but for now it's there.

Amazingly, despite using iterators, enumerators, high level for loops, function calls, etc, if we pop:

unsafe { (&*usb::pma::PMA.get()).write_buffer(0, &[0x1000, 0x2000, 0x3000]); }

into our main function and compile it, we end up with the instruction sequence:

80001e4: f246 0000 movw r0, #24576 ; 0x6000 80001e8: f44f 5180 mov.w r1, #4096 ; 0x1000 80001ec: f2c4 0000 movt r0, #16384 ; 0x4000 80001f0: 8001 strh r1, [r0, #0] 80001f2: f44f 5100 mov.w r1, #8192 ; 0x2000 80001f6: 8081 strh r1, [r0, #4] 80001f8: f44f 5140 mov.w r1, #12288 ; 0x3000 80001fc: 8101 strh r1, [r0, #8]

which, as you can see, ends up being three sequential halfword stores directly to the right locations in the CPU's view of the PMA. You have to love seriously aggressive compile-time optimisation

Hopefully, by next time, we'll have layered some more pleasant routines on our PMA code, and begun a foray into the setup necessary before we can begin handling interrupts and start turning up on a USB port.

Daniel Silverstone http://blog.digital-scurf.org/ Digital-Scurf Ramblings

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