We're excited to announce that Debian has selected 29 interns to work with us this summer: 4 in Outreachy, and 25 in the Google Summer of Code. Here is the list of projects and the interns who will work on them: Android SDK tools in Debian:

APT - dpkg communications rework:

David Kalnischkies

Continuous Integration for Debian-Med packages:

Extending the Debian Developer Horizon:

Harsh Daftary

Improving and extending AppRecommender:

Improving the debsources frontend:

Aaron Delaney

Improving voice, video and chat communication with Free Software:

MIPS and MIPSEL ports improvements:

Jonathan Jackson

Reproducible Builds for Debian and Free Software:

Support for KLEE in Debile:

Marko Dimja evi

The Google Summer of Code and Outreachy programs are possible in Debian thanks to the effort of Debian developers and contributors that dedicate part of their free time to mentor students and outreach tasks. Join us and help extend Debian! You can follow the students weekly reports on the debian-outreach mailing-list, chat with us on our IRC channel or on each project's team mailing lists. Congratulations to all of them!

It is 101 years to the day that Turkey started the first genocide of the 20th century, the Armenian Genocide. And Recep Tayyip Erdo an, the populistic and seemingly maniac president of Turkey, does not drop any chance to continue the shame of Turkey. armenien-genocide

After having sued a German comedian of making fun of him followed promptly by an as shameful cowtow of Merkel by allowing the jurisdiction to start prosecuting Jan B hmermann, heis continuing suing other journalists, and above all putting pressure on the European Community to not support a concert tour of the Dresdner Sinfoniker in memoriam of the genocide. European Values have disappeared, and politicians pay stupid tribute to a dictator-like Erdo an who is destroying free speech and free media, not only in his country but all around the world. Must be a good friend of Abe, both are installing anti-freedom laws. Shame on Europe for this. And Turkey, either vote Erdo an out of office, or you should not (and hopefully will never) be allowed into the EC, because you don t belong there.

Over the coming week, there are a vast number of free software events taking place around the world. I'll be at the LinuxWochen Vienna and MiniDebConf Vienna, the events run over four days from Thursday, 28 April to Sunday, 1 May. At MiniDebConf Vienna, I'll be giving a talk on Saturday (schedule not finalized yet) about our progress with free Real-Time Communications (RTC) and welcoming 13 new GSoC students (and their mentors) working on this topic under the Debian umbrella. On Sunday, Iain Learmonth and I will be collaborating on a workshop/demonstration on Software Defined Radio from the perspective of ham radio and the Debian Ham Radio Pure Blend. If you want to be an active participant, an easy way to get involved is to bring an RTL-SDR dongle. It is highly recommended that instead of buying any cheap generic dongle, you buy one with a high quality temperature compensated crystal oscillator (TXCO), such as those promoted by RTL-SDR.com. Saturday, 30 April is also Linux Presentation Day in many places. There is an event in Switzerland organized by the local local FSFE group in Basel. DebConf16 is only a couple of months away now, Registration is still open and the team are keenly looking for additional sponsors. Sponsors are a vital part of such a large event, if your employer or any other organization you know benefits from Debian, please encourage them to contribute.

Back in 2014, I wrote about some negative first impressions of systemd. I also had a plea to debian-project to end all the flaming, pointing out that jessie will still boot , noting that my preference was for sysvinit but things are what they are and it wasn t that big of a deal. Although I still have serious misgivings about the systemd upstream s attitude, I ve got to say I find the system rather refreshing and useful in practice. Here s an example. I was debugging the boot on a server recently. It mounts a bunch of NFS filesystems and runs a third-party daemon that is started from an old-style /etc/init.d script. We had a situation where the NFS filesystems the daemon required didn t mount on boot. The daemon then was started, and unfortunately it basically does a mkdir -p on startup. So it started running and processing requests with negative results. So there were two questions: why did the NFS filesystems fail to start, and how could we make sure the daemon wouldn t start without them mounted? For the first, journalctl -xb was immensely helpful. It logged the status of each individual mount, and it turned out that it looked like a modprobe or kernel race condition when a bunch of NFS mounts were kicked off in parallel and all tried to load the nfsv4 module at the same time. That was easy enough to work around by adding nfsv4 to /etc/modules. Now for the other question: refusing to start the daemon if the filesystems weren t there. With systemd, this was actually trivial. I created /etc/systemd/system/mydaemon.service.requires (I ll call the service mydaemon here), and in it I created a symlink to /lib/systemd/system/remote-fs.target. Then systemctl daemon-reload, and boom, done. systemctl list-dependencies mydaemon will even show the the dependency tree, color-coded status of each item on it, and will actually show every single filesystem that remote-fs requires and the status of it in one command. Super handy. In a non-systemd environment, I d probably be modifying the init script and doing a bunch of manual scripting to check the filesystems. Here, one symlink and one command did it, and I get tools to inspect the status of the mydaemon prerequisites for free. I ve got to say, as someone that has occasionally had to troubleshoot boot ordering and update-rc.d symlink hell, troubleshooting this stuff in systemd is considerably easier and the toolset is more powerful. Yes, it has its set of poorly-documented complexity, but then so did sysvinit. I never thought the world is falling folks were right, but by now I can be counted among those that feels like systemd has matured to the point where it truly is superior to sysvinit. Yes, in 2014 it had some bugs, but by here in 2016 it looks pretty darn good and I feel like Debian s decision has been validated through my actual experience with it.

Last week, someone posted a request for help on the popular Server Fault Q&A site: they had apparently accidentally deleted their entire web hosting business, and all their backups. The post (now itself deleted) was a reasonably obvious fake, but mainstream media reported on it anyway, and then life imitated art and 123-reg went and did actually delete all their hosted VMs, and their backups. I was chatting to some friends from $job-2 and we had a brief smug moment that we had never done anything this bad, before moving on to incredulity that we had never done anything this bad in the 5 years or so we were running the University web servers. Some time later I realised that my personal backups were at risk from something like this because I have a permanently mounted /backup partition on my home NAS. I decided to fix it. I already use Systemd to manage mounting the /backup partition (via a backup.mount file) and its dependencies. I'll skip the finer details of that for now. I planned to define some new Systemd units for each backup job which was previously scheduled via Cron in order that I could mark them as depending on the /backup mount. I needed to adjust that mount definition by adding StopWhenUnneeded=true. This ensures that /backup will be unmounted when it is not in use by another job, and not at risk of a stray rm -rf. The backup jobs are all simple shell scripts that convert quite easily into services. An example: backup-home.service:

[Unit]
Requires=backup.mount
After=backup.mount
[Service]
User=backupuser
Group=backupuser
ExecStart=/home/backupuser/bin/phobos-backup-home

To schedule this, I also need to create a timer: backup-home.timer:

[Timer]
OnCalendar=*-*-* 04:01:00
[Install]
WantedBy=timers.target

To enable the timer, you have to both enable and start it:

systemctl enable backup-home.timer
systemctl start backup-home.timer

I created service and timer units for each of my cron jobs. The other big difference to driving these from Cron is that by default I won't get any emails if the jobs generate output - in particular, if they fail. I definitely do want mail if things fail. The Arch Wiki has an interesting proposed solution to this which I took a look at. It's a bit clunky, and my initial experiments with a derivation from this (using mail(1) not sendmail(1)) have not yet generated any mail. Pros and Cons The Systemd timespec is more intuitive than Cron's. It's a shame you need a minimum of three more lines of boilerplate for the simplest of timers. I think WantedBy=timers.target should probably be an implicit default for all .timer type units. Here I think clarity suffers in the name of consistency. With timers, start doesn't kick-off the job, it really means "enable" in the context of timers, which is clumsy considering the existing enable verb, which seems almost superfluous, but is necessary for consistency, ~~since Systemd units need to be enabled before they can be started~~ As Simon points out in the comments, this is not true. Rather, "enable" is needed for the timer to be active upon subsequent boots, but won't enable it in the current boot. "Start" will enable it for the current boot, but not for subsequent ones. Since I need a .service and a .unit file for each active line in my crontab, that's a lot of small files (twice as many as the number of jobs being defined) and they're all stored in system-wide folder because of the dependency on the necessarily system-level units defining the mount. It's easy to forget the After= line for the backup services. On the one hand, it's a shame that After= doesn't imply Require=, so you don't need both; or alternatively there was a convenience option that did both. On the other hand, there are already too many Systemd options and adding more conjoined ones would just make it even more complicated. It's a shame I couldn't use user-level units to achieve this, but they could not depend on the system-level ones, nor activate /backup. This is a sensible default, since you don't want any user to be able to start any service on-demand, but some way of enabling it for these situations would be good. I ruled out systemd.automount because a stray rm -rf would trigger the mount which defeats the whole exercise. Apparently this might be something you solve with Polkit, as the Arch Wiki explains, which looks like it has XML disease. I need to get mail-on-error working reliably.

I've lately been working on support for Secure Boot in Debian, mostly in the packages maintained by the kernel team. My instructions for setting up UEFI Secure Boot are based on OVMF running on KVM/QEMU. All 'Designed for Windows' PCs should allow reconfiguration of SB, but it may not be easy to do so. ~~They also assume that the firmware includes an EFI shell.~~ Updated: Robert Edmonds pointed out that the 'Designed for Windows' requirements changed with Windows 10:

@benhutchingsuk "Hardware can be Designed for Windows 10 and can offer no way to opt out of the Secure Boot" https://t.co/lQVdPYtMwx Robert Edmonds (@rsedmonds) April 20, 2016

The ability to reconfigure SB is indeed now optional for devices which are designed to always boot with a specific Secure Boot configuration. I also noticed that the requirements say that OEMs should not sign an EFI shell binary. Therefore I've revised the instructions to use efibootmgr instead. Background UEFI Secure Boot, when configured and enabled (which it is on most new PCs) requires that whatever it loads is signed with a trusted key. The one common trusted key for PCs is held by Microsoft, and while they will sign other people's code for a nominal fee, they require that it also validates the code it loads, i.e. the kernel or next stage boot loader. The kernel in turn is responsible for validating any code that could compromise its integrity (kernel modules, kexec images). Currently there are no such signed boot loaders in Debian, though the shim and grub-signed packages included in many other distributions should be usable. However it's possible to load an appropriately configured Linux kernel directly from the UEFI firmware (typically through the shell) which is what I'm doing at the moment. Packaging signed kernels Signing keys obviously need to be protected against disclosure; the private keys can't be included in a source package. We also won't install them on buildds separately, and generating signatures at build time would of course be unreproducible. So I've created a new source package, linux-signed, which contains detached signatures prepared offline. Currently the binary packages built from linux-signed also contain only detached signatures, which are applied as necessary at installation time. The signed kernel image (only on x86 for now) is named /boot/vmlinuz-kversion.efi.signed. However, since packages must not modify files owned by another package and I didn't want to dpkg-divert thousands of modules, the module signatures remain detached. Detached module signatures are a new invention of mine, and require changes in kmod and various other packages to support them. (An alternate might be to put signed modules under a different directory and drop a configuration file in /lib/depmod.d to make them higher priority. But then we end up with two copies of every module installed, which can be a substantial waste of space.) Preparation The packages you need to repeat the experiment:

linux-image-4.5.0-1-flavour version 4.5.1-1 from unstable (only 686, 686-pae or amd64 flavours have signed kernels; most flavours have signed modules)
linux-image-4.5.0-1-flavour-signed version 1~exp3 from experimental
initramfs-tools version 0.125 from unstable
kmod and libkmod2 unofficial version 22-1.2 from people.debian.org

For Secure Boot, you'll then need to copy the signed kernel and the initrd onto the EFI system partition, normally mounted at /boot/efi. SB requires a Platform Key (PK) which will already be installed on a real PC. You can replace it but you don't need to. If you're using OVMF, there are no persistent keys so you do need to generate your own:

openssl req -new -x509 -newkey rsa:2048 -keyout pk.key -out pk.crt \
    -outform der -nodes

You'll also need to install the certificate for my kernel image signing key, which is under debian/certs in the linux-signed package. OVMF requires this in DER format:

openssl x509 -in linux-signed-1~exp3/debian/certs/linux-image-benh@debian.org.cert.pem \
    -out linux.crt -outform der

You'll need to copy the certificate(s) to a FAT-formatted partition such as the EFI system partition, so that the firmware can read it. Use efibootmgr to add a boot entry for the kernel, for example:

efibootmgr -c -d /dev/sda -L linux-signed -l '\vmlinuz.efi' -u 'initrd=initrd.img root=/dev/sda2 ro quiet'

You should use the same kernel parameters as usual, except that you also need to specify the initrd filename using the initrd= parameter. The EFI stub code at the beginning of the kernel will load the initrd using EFI boot services. Enabling Secure Boot

Reboot the system and enter UEFI setup
Find the menu entry for Secure Boot customisation (in OVMF, it's under 'Device Manager' for some reason)
In OVMF, enrol the PK from pk.crt
Add linux.crt to the DB (whitelist database)
Ensure that Secure Boot is enabled and in 'User Mode'

Booting the kernel in Secure Boot If all went well, Linux will boot as normal. You can confirm that Secure Boot was enabled by reading /sys/kernel/security/securelevel, which will contain 1 if it was. Module signature validation Module signatures are now always checked and unsigned modules will be given the 'E' taint flag. If Secure Boot is used or you add the kernel parameter module.sig_enforce=1, unsigned modules will be rejected. You can also turn on signature enforcement and turn off various other methods of modifying kernel code (such as kexec) by writing 1 to /sys/kernel/security/securelevel.

Switching from one GnuPG master key to the usage of subkeys was long on my list of things I wanted to do, but never came around. With the advent of a YubiKey NEO in my pocket I finally took the plunge: reading through lots of web pages (and adding one here for confusion), trying to understand the procedures, and above all, understanding my own requirements!

To sum up a long story, it was worth the plunge, and all over the security level of my working environment has improved considerable. While the advantages of subkeys are well documented (e.g., Debian Wiki), at the end of the day I was like probably many Debian Developers having one master key that was used for every action: mail decryption and signing, signing of uploads, etc. Traveling a lot I always felt uncomfortable. Despite a lengthy passphrase, I still didn t want my master key to get into wrong hands in case the laptop got stolen. Furthermore, I had my master key on several computers (work, laptop, mail server), which didn t help a lot either. With all this, I started to compile a list of requirements/objectives I wanted to have:

master key is only available on offline medium (USB sticks)
subkeys for signing, encryption, authentication
possibility to sign and decrypt my emails on the server where I read emails (ssh/mutt)
laptop does not contain any keys, instead use Yubikey
all keys with expiry date (1y)
mixture of gpg versions: local laptop: gpg2.1, mail server: gpg1

Warning Before we start a word of caution make backups, best is to make backups at every stage. You don t want that an erroneous operations wipes out your precious keys without a backup! Preparation In the following I will assume that MASTERKEY environment variable contains the id of the master key to be converted. Furthermore, I have followed some of the advice here, so key ids will be shown in long format. Let us start with the current situation:

$ gpg -K $MASTERKEY
sec   4096R/0x6CACA448860CDC13 2010-09-14
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                            Norbert Preining <norbert@preining.info>
uid                            Norbert Preining <preining@logic.at>
uid                            Norbert Preining <preining@debian.org>
uid                            Norbert Preining <preining@jaist.ac.jp>
ssb   4096R/0xD1D2BD14810F62B3 2010-09-14

In the following we will go through the following steps:

Prepare the Yubikey NEO (forthcoming blog>
Edit to current key: add expiry, add photo, and above all add subkeys
Create revocation certificate
Create gpg2.1 structure
Backup to USB media
Move subkeys to Yubikey NEO
Remove master keys
Separate gpg1 (for mail server) and gpg2 (for laptop)
Upload to key servers

Yubikey SmartCard setup There are several guides out there, but I will in very near future write one about using the NEO for various usage scenaria including GPG keys. Edit the current key The following can be done in one session or in different sessions, the screen logs are after starting with:

$ gpg --expert --edit-key $MASTERKEY

add expiry date Having an expiry date on your key serves two purposes: If you loose it, it will solve itself automatically, and furthermore, you are forced to deal with the key and refresh your gpg knowledge at least once a year. That are two perfect reasons to set expiry to one year. The following log selects each key in turn and sets its expiry date.

$ gpg --expert --edit-key $MASTERKEY
gpg (GnuPG) 1.4.20; Copyright (C) 2015 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
 
Secret key is available.
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: never       usage: SC  
                               trust: ultimate      validity: ultimate
sub  4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: never       usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
 
gpg> expire
Changing expiration time for the primary key.
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 1y
Key expires at Mon 06 Feb 2017 08:09:16 PM JST
Is this correct? (y/N) y
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub  4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: never       usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
 
gpg> key 1
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: never       usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
 
gpg> expire
Changing expiration time for a subkey.
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 1y
Key expires at Mon 06 Feb 2017 08:09:27 PM JST
Is this correct? (y/N) y
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>

Add a photo Not strictly necessary, but an interesting feature. gpg suggests 240 288, I resized a photo of my head, greyscaled it, and optimized it with jpegoptim -s -m40 my-photo.jpg. The parameter 40 is the quality, I played around a bit to find the best balance between size and quality. The size should not be too big as the photo will be part of the key!

gpg> addphoto
 
Pick an image to use for your photo ID.  The image must be a JPEG file.
Remember that the image is stored within your public key.  If you use a
very large picture, your key will become very large as well!
Keeping the image close to 240x288 is a good size to use.
 
Enter JPEG filename for photo ID: GPG/norbert-head.jpg
Is this photo correct (y/N/q)? y
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ unknown] (5)  [jpeg image of size 4185]

Add subkeys of 2048bit for signing/encryption/authentication Now comes the interesting part, adding three subkeys: one for signing, one for encrypting, and one for authentication. The one for signing is the one you will use for signing your uploads to Debian as well as emails. The authentication key will later be used to provide ssh authentication. Note that you have to use the --expert expert option to edit-key (as shown above), otherwise gpg does not allow to do this. As I want to move the subkeys to the Yubikey NEO, a keysize of 2048bits is necessary. First for the signing:

gpg> addkey
Key is protected.
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
Please select what kind of key you want:
   (3) DSA (sign only)
   (4) RSA (sign only)
   (5) Elgamal (encrypt only)
   (6) RSA (encrypt only)
   (7) DSA (set your own capabilities)
   (8) RSA (set your own capabilities)
Your selection? 4
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (2048) 
Requested keysize is 2048 bits
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 1y
Key expires at Mon 06 Feb 2017 08:10:06 PM JST
Is this correct? (y/N) y
Really create? (y/N) y
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
....+++++
..........+++++
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
sub  2048R/0xEC00B8DAD32266AA  created: 2016-02-07  expires: 2017-02-06  usage: S   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ unknown] (5)  [jpeg image of size 4185]

Now the same for encryption key:

gpg> addkey
Key is protected.
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
Please select what kind of key you want:
   (3) DSA (sign only)
   (4) RSA (sign only)
   (5) Elgamal (encrypt only)
   (6) RSA (encrypt only)
   (7) DSA (set your own capabilities)
   (8) RSA (set your own capabilities)
Your selection? 6
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (2048) 
Requested keysize is 2048 bits
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 1y
Key expires at Mon 06 Feb 2017 08:10:20 PM JST
Is this correct? (y/N) y
Really create? (y/N) y
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
..+++++
........+++++
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
sub  2048R/0xEC00B8DAD32266AA  created: 2016-02-07  expires: 2017-02-06  usage: S   
sub  2048R/0xBF361ED434425B4C  created: 2016-02-07  expires: 2017-02-06  usage: E   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ unknown] (5)  [jpeg image of size 4185]

Finally for the authentication key. Note that only here the --expert is necessary! We use (8) RSA (set your own capabilities) and then toggle sign and encryption capabilities off, and authentication on.

gpg> addkey
Key is protected.
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
Please select what kind of key you want:
   (3) DSA (sign only)
   (4) RSA (sign only)
   (5) Elgamal (encrypt only)
   (6) RSA (encrypt only)
   (7) DSA (set your own capabilities)
   (8) RSA (set your own capabilities)
Your selection? 8
 
Possible actions for a RSA key: Sign Encrypt Authenticate 
Current allowed actions: Sign Encrypt 
 
   (S) Toggle the sign capability
   (E) Toggle the encrypt capability
   (A) Toggle the authenticate capability
   (Q) Finished
 
Your selection? s
 
Possible actions for a RSA key: Sign Encrypt Authenticate 
Current allowed actions: Encrypt 
 
   (S) Toggle the sign capability
   (E) Toggle the encrypt capability
   (A) Toggle the authenticate capability
   (Q) Finished
 
Your selection? e
 
Possible actions for a RSA key: Sign Encrypt Authenticate 
Current allowed actions: 
 
   (S) Toggle the sign capability
   (E) Toggle the encrypt capability
   (A) Toggle the authenticate capability
   (Q) Finished
 
Your selection? a
 
Possible actions for a RSA key: Sign Encrypt Authenticate 
Current allowed actions: Authenticate 
 
   (S) Toggle the sign capability
   (E) Toggle the encrypt capability
   (A) Toggle the authenticate capability
   (Q) Finished
 
Your selection? q
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (2048) 
Requested keysize is 2048 bits
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
Key is valid for? (0) 1y
Key expires at Mon 06 Feb 2017 08:10:34 PM JST
Is this correct? (y/N) y
Really create? (y/N) y
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
......+++++
+++++
 
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub* 4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
sub  2048R/0xEC00B8DAD32266AA  created: 2016-02-07  expires: 2017-02-06  usage: S   
sub  2048R/0xBF361ED434425B4C  created: 2016-02-07  expires: 2017-02-06  usage: E   
sub  2048R/0x9C7CA4E294F04D49  created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ unknown] (5)  [jpeg image of size 4185]
 
gpg> save

Check the current status Good point to take a break and inspect the current status. We should have one main key and three subkeys, all with expiry dates of 1 year ahead, and a photo also attached to the key:

$ gpg --expert --edit-key $MASTERKEY
gpg (GnuPG) 1.4.20; Copyright (C) 2015 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
 
Secret key is available.
 
gpg: checking the trustdb
gpg: public key 0x0FC3EC02FBBB8AB1 is 58138 seconds newer than the signature
gpg: 3 marginal(s) needed, 1 complete(s) needed, classic trust model
gpg: depth: 0  valid:   2  signed:  28  trust: 0-, 0q, 0n, 0m, 0f, 2u
gpg: depth: 1  valid:  28  signed:  41  trust: 28-, 0q, 0n, 0m, 0f, 0u
gpg: next trustdb check due at 2016-11-02
pub  4096R/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06  usage: SC  
                               trust: ultimate      validity: ultimate
sub  4096R/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06  usage: E   
sub  2048R/0xEC00B8DAD32266AA  created: 2016-02-07  expires: 2017-02-06  usage: S   
sub  2048R/0xBF361ED434425B4C  created: 2016-02-07  expires: 2017-02-06  usage: E   
sub  2048R/0x9C7CA4E294F04D49  created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg>

Create revocation certificate In case something happens, like all your backups are burned, your computers are destroyed, or all data stolen by the NSA, it is a good idea to have an old fashioned paper print out of a revocation certificate which allows you to revoke the key even if you are not in possession of it. This should be printed out and kept in a safe place.

$ gpg --gen-revoke $MASTERKEY > GPG/revoke-certificate-$MASTERKEY.txt
 
sec  4096R/0x6CACA448860CDC13 2010-09-14 Norbert Preining <norbert@preining.info>
 
Create a revocation certificate for this key? (y/N) y
Please select the reason for the revocation:
  0 = No reason specified
  1 = Key has been compromised
  2 = Key is superseded
  3 = Key is no longer used
  Q = Cancel
(Probably you want to select 1 here)
Your decision? 1
Enter an optional description; end it with an empty line:
> 
Reason for revocation: Key has been compromised
(No description given)
Is this okay? (y/N) y
 
You need a passphrase to unlock the secret key for
user: "Norbert Preining <norbert@preining.info>"
4096-bit RSA key, ID 0x6CACA448860CDC13, created 2010-09-14
 
Enter passphrase:
 
ASCII armored output forced.
Revocation certificate created.

Please move it to a medium which you can hide away; if the NSA or KGB or Mossad gets access to this certificate, they can use it to make your key unusable. It is smart to print this certificate and store it away, just in case your media become unreadable. Create gpg 2.1 structure There are currently three versions of gpg available: classic (version 1) which is one static binary, perfect for servers or scripting tasks; stable (version 2.0) which is the modularized version supporting OpenPGP, S/MIME, and Secure Shell; and finally modern (version 2.1 and up) with enhanced features like support for Elliptic Curve cryptography. Debian currently ships version 1 as standard, and also the modern version (but there are traces in experimental of a pending transition). The newer versions of GnuPG are modularized and use an agent. For the following we need to kill any running instance of gpg-agent.

$ killall gpg-agent

After that a simple call to gpg2 to list the secret keys will convert the layout to the new standard:

$ gpg2 -K $MASTERKEY
gpg: keyserver option 'ca-cert-file' is obsolete; please use 'hkp-cacert' in dirmngr.conf
gpg: starting migration from earlier GnuPG versions
gpg: porting secret keys from '/home/norbert/.gnupg/secring.gpg' to gpg-agent
gpg: key 0xD2BF4AA309C5B094: secret key imported
gpg: key 0x6CACA448860CDC13: secret key imported
gpg: migration succeeded
sec   rsa4096/0x6CACA448860CDC13 2010-09-14 [SC] [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                   [ultimate] Norbert Preining <norbert@preining.info>
uid                   [ultimate] Norbert Preining <preining@logic.at>
uid                   [ultimate] Norbert Preining <preining@debian.org>
uid                   [ultimate] Norbert Preining <preining@jaist.ac.jp>
uid                   [ultimate] [jpeg image of size 4185]
ssb   rsa4096/0xD1D2BD14810F62B3 2010-09-14 [E] [expires: 2017-02-06]
ssb   rsa2048/0xEC00B8DAD32266AA 2016-02-07 [S] [expires: 2017-02-06]
ssb   rsa2048/0xBF361ED434425B4C 2016-02-07 [E] [expires: 2017-02-06]
ssb   rsa2048/0x9C7CA4E294F04D49 2016-02-07 [A] [expires: 2017-02-06]

After this there will be new files/directories in the .gnupg directory, in particular: .gnupg/private-keys-v1.d/ which contains the private keys. Creating backup Now your .gnupg directory contains still all the keys, available for gpg1 and gpg2.1. You MUST MAKE A BACKUP NOW!!! on at least 3 USB sticks and maybe some other offline media. Keep them in a safe place, better in different and safe places, you will need them for extending the expiry date, signing other keys, etc. Warning concerning USB and vfat file systems gpg >= 2.1 requires gpg-agent which in turn needs a socket. If you have the backup on an USB drive (most often with vfat file system), you need to redirect the socket, as vfat does not support sockets! Edit /USBSTICK/gnupghome/S.gpg-agent and enter there

%Assuan%
socket=/dev/shm/S.gpg-agent

After that the socket will be created in /dev/shm/ instead and invoking gpg with gpg2 --homedir /USBSTICK/gnupghome will work. You have done your backups, right? Move sub keys to card As I mentioned, I want to have no keys on my laptop which I carry around to strange countries, instead I want to have them all on a Yubikey NEO. I will describe the setup and usage in details soon, but mention here only how to move the keys to the card. This requires a finished setup including change of pins. Note that when using gpg2 to move the keys to the card, the local copies are actually deleted, but only for the gpg2(.1) files. The gpg1 secret keys are still all in place.

$ gpg2 --edit-key $MASTERKEY
gpg (GnuPG) 2.1.11; Copyright (C) 2016 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
 
Secret key is available.
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 2
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb* rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> keytocard
Please select where to store the key:
   (1) Signature key
   (3) Authentication key
Your selection? 1
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb* rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 2
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 3
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb* rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> keytocard
Please select where to store the key:
   (2) Encryption key
Your selection? 2
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb* rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 3
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 4
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb* rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> keytocard
Please select where to store the key:
   (3) Authentication key
Your selection? 3
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb* rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> key 4
 
sec  rsa4096/0x6CACA448860CDC13
     created: 2010-09-14  expires: 2017-02-06  usage: SC  
     trust: ultimate      validity: ultimate
ssb  rsa4096/0xD1D2BD14810F62B3
     created: 2010-09-14  expires: 2017-02-06  usage: E   
ssb  rsa2048/0xEC00B8DAD32266AA
     created: 2016-02-07  expires: 2017-02-06  usage: S   
ssb  rsa2048/0xBF361ED434425B4C
     created: 2016-02-07  expires: 2017-02-06  usage: E   
ssb  rsa2048/0x9C7CA4E294F04D49
     created: 2016-02-07  expires: 2017-02-06  usage: A   
[ultimate] (1). Norbert Preining <norbert@preining.info>
[ultimate] (2)  Norbert Preining <preining@logic.at>
[ultimate] (3)  Norbert Preining <preining@debian.org>
[ultimate] (4)  Norbert Preining <preining@jaist.ac.jp>
[ultimate] (5)  [jpeg image of size 4185]
 
gpg> save

Note the repetition of selecting and deselecting keys. Current status After this procedure we are now in the following situation:

gpg1: all keys are still available
gpg2: sub keys are moved to yubikey (indicated below by ssb>), and master key is still available

In gpg words it looks like this:

$ gpg2 -K $MASTERKEY
gpg: keyserver option 'ca-cert-file' is obsolete; please use 'hkp-cacert' in dirmngr.conf
sec   rsa4096/0x6CACA448860CDC13 2010-09-14 [SC] [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                   [ultimate] Norbert Preining <norbert@preining.info>
uid                   [ultimate] Norbert Preining <preining@logic.at>
uid                   [ultimate] Norbert Preining <preining@debian.org>
uid                   [ultimate] Norbert Preining <preining@jaist.ac.jp>
uid                   [ultimate] [jpeg image of size 4185]
ssb   rsa4096/0xD1D2BD14810F62B3 2010-09-14 [E] [expires: 2017-02-06]
ssb>  rsa2048/0xEC00B8DAD32266AA 2016-02-07 [S] [expires: 2017-02-06]
ssb>  rsa2048/0xBF361ED434425B4C 2016-02-07 [E] [expires: 2017-02-06]
ssb>  rsa2048/0x9C7CA4E294F04D49 2016-02-07 [A] [expires: 2017-02-06]
 
$ gpg -K $MASTERKEY
sec   4096R/0x6CACA448860CDC13 2010-09-14 [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                            Norbert Preining <norbert@preining.info>
uid                            Norbert Preining <preining@logic.at>
uid                            Norbert Preining <preining@debian.org>
uid                            Norbert Preining <preining@jaist.ac.jp>
uid                            [jpeg image of size 4185]
ssb   4096R/0xD1D2BD14810F62B3 2010-09-14 [expires: 2017-02-06]
ssb   2048R/0xEC00B8DAD32266AA 2016-02-07 [expires: 2017-02-06]
ssb   2048R/0xBF361ED434425B4C 2016-02-07 [expires: 2017-02-06]
ssb   2048R/0x9C7CA4E294F04D49 2016-02-07 [expires: 2017-02-06]
 
$ gpg2 --card-status
 
....
Name of cardholder: Norbert Preining
....
PIN retry counter : 3 3 3
Signature counter : 0
Signature key ....: 5871 F824 2DCC 3660 2362  BE7D EC00 B8DA D322 66AA
      created ....: 2016-02-07 11:10:06
Encryption key....: 2501 195C 90AB F4D2 3DEA  A303 BF36 1ED4 3442 5B4C
      created ....: 2016-02-07 11:10:20
Authentication key: 9CFB 3775 C164 0E99 F0C8  014C 9C7C A4E2 94F0 4D49
      created ....: 2016-02-07 11:10:34
General key info..: sub  rsa2048/0xEC00B8DAD32266AA 2016-02-07 Norbert Preining <norbert@preining.info>
sec   rsa4096/0x6CACA448860CDC13  created: 2010-09-14  expires: 2017-02-06
ssb   rsa4096/0xD1D2BD14810F62B3  created: 2010-09-14  expires: 2017-02-06
ssb>  rsa2048/0xEC00B8DAD32266AA  created: 2016-02-07  expires: 2017-02-06
                                  card-no: 0006 03645719
ssb>  rsa2048/0xBF361ED434425B4C  created: 2016-02-07  expires: 2017-02-06
                                  card-no: 0006 03645719
ssb>  rsa2048/0x9C7CA4E294F04D49  created: 2016-02-07  expires: 2017-02-06
                                  card-no: 0006 03645719
$

Remove private master keys You are sure that you have a working backup? Did you try it with gpg --homedir ...? Only if you are really sure, continue. We are now removing the master key from both the gpg2 and gpg1 setup. removal for gpg2 gpg2 keeps the private keys in ~/.gnupg/private-keys-v1.d/KEYGRIP.key and the KEYGRIP can be found by adding --with-keygrip to the key listing. Be sure to delete the correct file, the one related to the master key.

$ gpg2 --with-keygrip --list-key $MASTERKEY
pub   rsa4096/0x6CACA448860CDC13 2010-09-14 [SC] [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
      Keygrip = 9DC1E90703856C1DE0EAC970CED7ABF5EE5EF79D
uid                   [ultimate] Norbert Preining <norbert@preining.info>
uid                   [ultimate] Norbert Preining <preining@logic.at>
uid                   [ultimate] Norbert Preining <preining@debian.org>
uid                   [ultimate] Norbert Preining <preining@jaist.ac.jp>
uid                   [ultimate] [jpeg image of size 4185]
sub   rsa4096/0xD1D2BD14810F62B3 2010-09-14 [E] [expires: 2017-02-06]
      Keygrip = 4B8FF57434DD989243666377376903281D861596
sub   rsa2048/0xEC00B8DAD32266AA 2016-02-07 [S] [expires: 2017-02-06]
      Keygrip = 39B14EF1392F2F251863A87AE4D44CE502755C39
sub   rsa2048/0xBF361ED434425B4C 2016-02-07 [E] [expires: 2017-02-06]
      Keygrip = E41C8DDB2A22976AE0DA8D7D11F586EA793203EA
sub   rsa2048/0x9C7CA4E294F04D49 2016-02-07 [A] [expires: 2017-02-06]
      Keygrip = A337DE390143074C6DBFEA64224359B9859B02FC
 
$ rm ~/.gnupg/private-keys-v1.d/9DC1E90703856C1DE0EAC970CED7ABF5EE5EF79D.key
$

After that the missing key is shown in gpg2 -K with an additional # meaning that the key is not available:

$ gpg2 -K $MASTERKEY
sec#  rsa4096/0x6CACA448860CDC13 2010-09-14 [SC] [expires: 2017-02-06]
...

removal for gpg1 Up to gpg v2.0 there is no simple way to delete only one part of the key. We export the subkeys, delete the private key, and reimport the subkeys:

$ gpg --output secret-subkeys --export-secret-subkeys $MASTERKEY
 
$ gpg --delete-secret-keys $MASTERKEY
 
sec  4096R/0x6CACA448860CDC13 2010-09-14 Norbert Preining <norbert@preining.info>
 
Delete this key from the keyring? (y/N) y
This is a secret key! - really delete? (y/N) y
 
$ gpg --import secret-subkeys
gpg: key 0x6CACA448860CDC13: secret key imported
gpg: key 0x6CACA448860CDC13: "Norbert Preining <norbert@preining.info>" not changed
gpg: Total number processed: 1
gpg:              unchanged: 1
gpg:       secret keys read: 1
gpg:   secret keys imported: 1
 
$

Current status We are basically at the stage we wanted to achieve: For gpg2.1 only the old encryption key is available, the master key is not, and the other sub keys are moved to the yubikey:

$ gpg2 -K $MASTERKEY
sec#  rsa4096/0x6CACA448860CDC13 2010-09-14 [SC] [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                   [ultimate] Norbert Preining <norbert@preining.info>
uid                   [ultimate] Norbert Preining <preining@logic.at>
uid                   [ultimate] Norbert Preining <preining@debian.org>
uid                   [ultimate] Norbert Preining <preining@jaist.ac.jp>
uid                   [ultimate] [jpeg image of size 4185]
ssb   rsa4096/0xD1D2BD14810F62B3 2010-09-14 [E] [expires: 2017-02-06]
ssb>  rsa2048/0xEC00B8DAD32266AA 2016-02-07 [S] [expires: 2017-02-06]
ssb>  rsa2048/0xBF361ED434425B4C 2016-02-07 [E] [expires: 2017-02-06]
ssb>  rsa2048/0x9C7CA4E294F04D49 2016-02-07 [A] [expires: 2017-02-06]
$

And for gpg <= 2.0 the old encryption key and the sub keys are available, but the master key is not:

$ gpg -K $MASTERKEY
sec#  4096R/0x6CACA448860CDC13 2010-09-14 [expires: 2017-02-06]
      Key fingerprint = F7D8 A928 26E3 16A1 9FA0  ACF0 6CAC A448 860C DC13
uid                            Norbert Preining <norbert@preining.info>
uid                            Norbert Preining <preining@logic.at>
uid                            Norbert Preining <preining@debian.org>
uid                            Norbert Preining <preining@jaist.ac.jp>
uid                            [jpeg image of size 4185]
ssb   4096R/0xD1D2BD14810F62B3 2010-09-14 [expires: 2017-02-06]
ssb   2048R/0xEC00B8DAD32266AA 2016-02-07 [expires: 2017-02-06]
ssb   2048R/0xBF361ED434425B4C 2016-02-07 [expires: 2017-02-06]
ssb   2048R/0x9C7CA4E294F04D49 2016-02-07 [expires: 2017-02-06]
 
$

Split the .gnupg directory for mail server and laptop As mentioned, I want to have a gpg1 version available at the server where I read my emails, and be able to sign/encrypt emails there, while on my laptop no secret key is available. Thus I prepare two gnupg directories. For the mailserver the gpg2 specific files are removed:

$ cp -a .gnupg .gnupg-mail
$ cd .gnupg-mail
$ rm -rf private-keys-v1.d/ pubring.gpg~ reader_0.status
$ rm -rf S.gpg-agent* S.scdaemon .gpg-v21-migrated

On my laptop, where I did all this operation, I remove the gpg1 files, namely the outdated secring.gpg:

$ cd $HOME/.gnupg
$ rm secring.gpg

As a last step I move the .gnupg-mail directory to my mail server. Once could *expire* the old encryption key, but for now I leave it as is. Upload keys to keyservers If you are a Debian Developer, a simple update of your master key will suffice:

gpg --keyserver hkp://keyring.debian.org --send-key YOURMASTERKEYID

Note that the update from the keyring server to the actual Debian keyring takes up to one month. Until that time either do not upload anything, or use the (offline) master key for signing. After your key has been updated in the Debian keyring, signatures made with the signing subkey will be accepted for uploading to Debian. It might be also a good idea to upload your new keys to some keyservers like:

gpg --keyserver hkp://pool.sks-keyservers.net --send-key $MASTERKEY

Now you an also fix the configuration file skew between gpg1 and gpg2. Further remark I am currently trying to use the authentication key from my Yubikey NEO as ssh key, but bugs (see #795368 and #818969) prohibit it at the moment. Raphael Herzog gave a possible fix by killing the gpg-agent and restarting it with gpg-agent --daemon from an X terminal, and I can confirm that this worked. After one year before the key expires I need to extend the key validity for another year. For this you need the offline master key. I will describe the process when it becomes necessary. Reading list The following web sites have been useful in collecting the necessary information:

https://iain.learmonth.me/yubikey-neo-gpg/
https://iain.learmonth.me/yubikey-udev/
http://blog.josefsson.org/2014/06/23/offline-gnupg-master-key-and-subkeys-on-yubikey-neo-smartcard/
https://wiki.debian.org/Subkeys
https://jclement.ca/articles/2015/gpg-smartcard/ as modernized version of (3)
https://www.esev.com/blog/post/2015-01-pgp-ssh-key-on-yubikey-neo/ similar style, with ssh and gnome-keyring infos
http://karlgrz.com/2fa-gpg-ssh-keys-with-pass-and-yubikey-neo/ also good reading
https://help.riseup.net/en/security/message-security/openpgp/best-practices good and concise advise on gpg practices

My writing is mostly based on (5) with additions from (4). Please let me know of any errors, improvements, and fixes. I hope this walk-through might help others in the same situation.

Although, AWS provides load balancer service in the form of Elastic Load Balancer (ELB), a common trick is to use HAProxy in the middle to provide SSL offloading, complex routing and better logging.
In this scenario, a public ELB is the frontier of all the traffic, HAProxy farm in the middle is managed by an Auto Scaling Group, and one (or more) internal backend ELBs stay in front of Web farm. haproxy

I think that HAProxy does not need any introductions here. It is highly scalable and reliable piece of software. There is however a small caveat when you use it with domain names and not IP addresses. To speed up things, HAProxy resolves all the domain named during startup (during config file parsing in fact). Hence, when the IP of a domain changes, you end up with a lot of 503s (Service Unavailable). Why is this important ? In AWS, ELB's IP can change over time, so it is recommended to use ELB's domain name. Now, when you use this domain name in HAProxy's backend, you can end up with 503s. ELB IPs do not change so often but still you would not want any downtimes. The solution is to configure runtime resolvers in HAProxy and use them in the backend (unforntunatelly this works only in HAProxy 1.6):

 ::haproxy
 resolvers myresolver
      nameserver dns1 10.10.10.10:53
      resolve_retries       30
      timeout retry         1s
      hold valid           10s
  backend mybackend
      server myelb-internal.123456.eu-west-1.elb.amazonaws.com check resolvers myresolver

Now HAProxy will check the domain at runtime, no more 503s.

flash that is used by Bosca Ceoil (but Bosca Ceoil is a free software).

What happened in the reproducible builds effort between April 3rd and April 9th 2016: Media coverage Emily Ratliff wrote an article for SecurityWeek called Establishing Correspondence Between an Application and its Source Code - How Combining Two Completely Separate Open Source Projects Can Make Us All More Secure. Tails have started work on a design for freezable APT repositories to make it easier and practical to perform reproductions of an entire distribution at a given point in time, which will be needed to create reproducible installation- or live-media. Toolchain fixes Alexis Bienven e submitted patches adding support for SOURCE_DATE_EPOCH in several tools: transfig, imagemagick, rdtool, and asciidoctor. boyska submitted one for python-reportlab. Packages fixed The following packages have become reproducible due to changes in their build dependencies: atinject-jsr330 brailleutils cglib3 gnugo libcobra-java libgnumail-java libjchart2d-java libjcommon-java libjfreechart-java libjide-oss-java liblaf-widget-java liblastfm-java liboptions-java octave-control octave-mpi octave-nan octave-parallel octave-stk octave-struct octave-tsa oar The following packages became reproducible after getting fixed:

apt-listchanges/2.88 by Robert Luberda.
cgal/4.8-1 by Joachim Reichel.
erlang-bitcask/2.0.2+dfsg-1 by Nobuhiro Iwamatsu.
geneweb/6.08+git20160228+dfsg-2 by Guillaume Brochu.
glance/2:12.0.0~rc2-1 uploaded by Thomas Goirand, original patch by Chris Lamb.
gle-graphics/4.2.5-4 by Christian T. Steigies.
maude uploaded by Andreas Tille, patch by Alexis Bienven e.
psqlodbc/1:09.05.0100-3 by Christoph Berg.
resource-agents/1:3.9.7-3 by Christoph Berg.
vgabios/0.7a-6 by Reiner Herrmann.
vim/2:7.4.1689-2 by James McCoy.
xmhtml/1.1.10-2 by Graham Inggs with Reiner Herrmann's help.
xscreensaver/5.34-2 uploaded by Tormod Volden, original patch by Sascha Steinbiss.

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

rkward/0.6.5-1 uploaded by Thomas Friedrichsmeier, original patch by Philip Rinn.
mailfilter/0.8.4-1 uploaded by Elimar Riesebieter, original patch by Chris Lamb.
bind9/1:9.10.3.dfsg.P4-6 uploaded by Michael Gilbert, original patch by Reiner Herrmann.
bzr/2.7.0- 3,4 by Jelmer Vernooij.
samba/2:4.3.6+dfsg-2 uploaded by Mathieu Parent, fix by Jelmer Vernooij.
fwupdate/0.5-3 by Mario Limonciello.
paraview/5.0.1+dfsg1-1 by Anton Gladky.

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

#819883 on debootstrap by Reiner Herrmann: tell tar to sort the archive members.
#819885 on chktex by Sascha Steinbiss: use the time of latest debian/changelog entry as documentation timestamp.
#819915 on kannel by Alexis Bienven e: use the time of latest debian/changelog entry as documentation timestamp.
#819921 on basket by Alexis Bienven e: remove build date from debug info.
#819965 on openarena-data by Alexandre Detiste: normalize file permissions before creating .pk3 archive.
#820016 on gabedit by Alexis Bienven e: sort object files used to build the executable.
#820032 on bibledit-gtk by Alexis Bienven e: remove useless included Makefile.
#820072 on synfig by Alexis Bienven e: remove build date from info output.
#820148 on autopkgtest by Alexis Bienven e: fix install order to cope with locales with case insensitive globbing.
#820152 on anope by Alexis Bienven e: remove build date from the version string.
#820179 on aodh by Alexis Bienven e: remove build date from the documentation.
#820183 on cython by Alexis Bienven e: add support SOURCE_DATE_EPOCH.
#820194 on nasm by rain1: sorts keys when traversing hash tables used to build the documentation.
#820226 on chrony by Alexis Bienven e: add support for SOURCE_DATE_EPOCH to preset the ntp_era_split parameter.
#820457 on recode by Alexis Bienven e: use system help2man.
#820522 on gtkspell by Alexis Bienven e: force shell to /bin/sh in example Makefile.

Other upstream fixes Alexander Batischev made a commit to make newsbeuter reproducible. tests.reproducible-builds.org

An architecture agnostic summary has been added to the reproducible-tracker.json by Valerie Young to make it easy to parse whether a package is unreproducible anywhere.
To find more reproducibility issues a new variation was added to the i386 builders, so that one build is done using a 32 bit kernel (686-PAE) and the other build is using a 64 bit kernel (amd64). (h01ger)
- Niko Tyni was the first to notice a bug due to this: #821182 perl: embeds kernel architecture information
The 2nd builds are now done in fr_CH on amd64, de_CH on i386 and it_CH on armhf. (h01ger)
The variation table has been updated to reflect the recent changes and various small bugs have been fixed. (h01ger)

Package reviews 93 reviews have been removed, 66 added and 21 updated in the previous week. 12 new FTBFS bugs have been reported by Chris Lamb and Niko Tyni. Misc. This week's edition was written by Lunar, Holger Levsen, Reiner Herrmann, Mattia Rizzolo and Ximin Luo. With the departure of Lunar as a full-time contributor, Reproducible Builds Weekly News (this thing you're reading) has moved from his personal Debian blog on Debian People to the Reproducible Builds team web site on Debian Alioth. You may want to update your RSS or Atom feeds. Very many thanks to Lunar for writing and publishing this weekly news for so long, well & continously!

Yes, I m going to DebConf 16! This year DebConf the Debian Developer Conference will take place in Cape Town, South Africa. Outbound: 2016-06-26 15:40 VIE -> 17:10 LHR BA0703
2016-06-26 21:30 LHR -> 09:55 CPT BA0059 Inbound: 2016-07-09 19:30 CPT > 06:15 LHR BA0058
2016-07-10 07:55 LHR > 11:05 VIE BA0696

Whoop! Looking forward to it already (though will probably spend it feeling I should be finishing my dissertation). Outbound:

2016-07-01 15:20 DUB -> 16:45 LHR BA0837
2016-07-01 21:35 LHR -> 10:00 CPT BA0059

Inbound:

2016-07-10 19:20 CPT -> 06:15 LHR BA0058
2016-07-11 09:20 LHR -> 10:45 DUB BA0828

(image stolen from Gunnar)

Whoop! Looking forward to it already (though will probably spend it feeling I should be finishing my dissertation). Outbound:

2016-07-01 15:20 DUB -> 16:45 LHR BA0837
2016-07-01 21:35 LHR -> 10:00 CPT BA0059

Inbound:

2016-07-10 19:20 CPT -> 06:15 LHR BA0058
2016-07-11 09:20 LHR -> 10:45 DUB BA0828

(image stolen from Gunnar)

It is days like today I am really happy to be a member of the Norwegian Unix User group, a member association for those of us believing in free software, open standards and unix-like operating systems. NUUG announced today it will try to bring the seizure of the DNS domain popcorn-time.no as unlawful, to stand up for the principle that writing about a controversial topic is not infringing copyrights, and censuring web pages by hijacking DNS domain should be decided by the courts, not the police. The DNS domain was seized by the Norwegian National Authority for Investigation and Prosecution of Economic and Environmental Crime a month ago. I hope this bring more paying members to NUUG to give the association the financial muscle needed to bring this case as far as it must go to stop this kind of DNS hijacking.

Preparation for the release of TeX Live 2016 have started some time ago with the freeze of updates in TeX Live 2015. Yesterday we announced the official start of the pretest period. That means that we invite people to test the new release and help fixing bugs. At the same time I have uploaded the first set of packages of TeX Live 2016 for Debian to the experimental suite. texlive-2016-debian-pretest

Concerning the binaries we do expect a few further changes, but hopefully nothing drastic. The most invasive change on the tlmgr side is that cryptographic signatures are now verified to guarantee authenticity of the packages downloaded, but this is rather irrelevant for Debian users (though I will look into how that works in user mode). Other than that, many packages have been updated or added since the last Debian packages, here is the unified list: acro, animate, appendixnumberbeamer, arabluatex, asapsym, asciilist, babel-belarusian, bibarts, biblatex-bookinarticle, biblatex-bookinother, biblatex-caspervector, biblatex-chicago, biblatex-gost, biblatex-ieee, biblatex-morenames, biblatex-opcit-booktitle, bibtexperllibs, bxdvidriver, bxenclose, bxjscls, bxnewfont, bxpapersize, chemnum, cjk-ko, cochineal, csplain, cstex, datetime2-finnish, denisbdoc, dtx, dvipdfmx-def, ejpecp, emisa, fithesis, fnpct, font-change-xetex, forest, formation-latex-ul, gregoriotex, gzt, hausarbeit-jura, hyperxmp, imakeidx, jacow, l3, l3kernel, l3packages, latex2e, latex2e-help-texinfo-fr, latex-bib2-ex, libertinust1math, lollipop, lt3graph, lua-check-hyphen, lualibs, luamplib, luatexja, mathalfa, mathastext, mcf2graph, media9, metrix, nameauth, ndsu-thesis, newtx, normalcolor, noto, nucleardata, nwejm, ocgx2, pdfcomment, pdfpages, pkuthss, polyglossia, proposal, qcircuit, reledmac, rmathbr, savetrees, scanpages, stex, suftesi, svrsymbols, teubner, tex4ebook, tex-ini-files, tikzmark, tikzsymbols, titlesec, tudscr, typed-checklist, ulthese, visualtikz, xespotcolor, xetex-def, xetexko, ycbook, yinit-otf. Enjoy.

Around a year ago I wrote some patches in an attempt to improve power management on Haswell and Broadwell systems by configuring Serial ATA power management appropriately. I got a couple of reports of them triggering SATA errors for some users, couldn't reproduce them myself and so didn't have a lot of confidence in them. Time passed.

I've been working on power management stuff again this week, so it seemed like a good opportunity to revisit these. I've made a few changes and pushed a couple of trees - one against master and one against 4.5.

First, these probably only have relevance to users of mobile Intel parts in the U or S range (/proc/cpuinfo will tell you - you're looking for a four-digit number that starts with 4 (Haswell), 5 (Broadwell) or 6 (Skylake) and ends with U or S), and won't do anything unless you have SATA drives (including PCI-based SATA). To test them, first disable anything like TLP that might alter your SATA link power management policy. Then check powertop - you should only be getting to PC3 at best. Build a kernel with these patches and boot it. /sys/class/scsi_host/*/link_power_management_policy should read "firmware". Check powertop and see whether you're getting into deeper PC states. Now run your system for a while and check the kernel log for any SATA errors that you didn't see before.

Let me know if you see SATA errors and are willing to help debug this, and leave a comment if you don't see any improvement in PC states.

comments

On my Debian machines I run stunnel to create an secure connection to my e-mail provider s SMTP gateway. Postfix sends mail through that TLS tunnel. Recently I stopped receiving e-mail from rss2email and I discovered tonight that the reason was that the tunnel has caved in on the machine which rss2email was running on. Unfortunately, some mail was permanently discarded from the postfix queue because it turns out that postfix will by default keep mail in the queue for a maximum of only 5 days. Since the connection to the gateway was down, postfix couldn t return the mail to its sender (i.e. me). Fortunately, I m not smart enough to have any log rotation going on, so I could easily find the message that were lost:

grep "status=expired, returned to sender" /var/log/mail.log \
      awk ' print $6 ' \
      while read id; do grep "$id" -m1 /var/log/mail.log; done

The first grep determines the queue id of the messages that were expired, and then the second grep finds the first entry in the mail log for that message, which provides the time the message was sent. Replacing -m1 with -m4 gave me the message-id of the messages and the intended recipient of the messages. This allowed me to restore them from backups or bounce them from my sent mail folder for those that I tried to send myself. To prevent this from happening again, I ve extended the maximum lifetime of messages in the queue from 5 days to 10:

postconf -e maximal_queue_lifetime=10d

I ve incorporated a check for clogged mail queues on my machines into my weekly backup routine.

As a rule, I avoid writing publicly on political topics, but I m making an exception. In case you haven t been following it, the senior Republican and the senior Democrat on the Senate Intelligence Committee recently announced a legislative proposal misleadingly called the Compliance with Court Orders Act of 2016. The full text of the draft can be found here. It would effectively ban devices and software in the United States that the manufacturer cannot retrieve data from. Here is a good analysis of the breadth of the proposal and a good analysis of the bill itself. While complying with court orders might sound great in theory, in practice this means these devices and software will be insecure by design. While that s probably reasonably obvious to most normal readers here, don t just take my word for it, take Bruce Schneier s. In my opinion, policy makers (and it s not just in the United States) are suffering from a perception gap about security and how technically hard it is to get right. It seems to me that they are convinced that technologists could just do security right while still allowing some level of extraordinary access for law enforcement if they only wanted to. We ve tried this before and the story never seems to end well. This isn t a complaint from wide eyed radicals that such extraordinary access is morally wrong or inappropriate. It s hard core technologists saying it can t be done. I don t know how to get the message across. Here s President Obama, in my opinion, completely missing the point when he equates a desire for security with fetishizing our phones above every other value. Here are some very smart people trying very hard to be reasonable about some mythical middle ground. As Riana Pfefferkorn s analysis that I linked in the first paragraph discusses, this middle ground doesn t exist and all the arm waving in the world by policy makers won t create it. Coincidentally, this same week, the White House announced a new Commission on Enhancing National Cybersecurity . Cybersecurity is certainly something we could use more of, unfortunately Congress seems to be heading off in the opposite direction and no one from the executive branch has spoken out against it. Security and privacy are important to many people. Given the personal and financial importance of data stored in computers (traditional or mobile), users don t want criminals to get a hold of it. Companies know this, which is why both Apple IOS and Google Android both encrypt their local file systems by default now. If a bill anything like what s been proposed becomes law, users that care about security are going to go elsewhere. That may end up being non-US companies products or US companies may shift operations to localities more friendly to secure design. Either way, the US tech sector loses. A more accurate title would have been Technology Jobs Off-Shoring Act of 2016. EDIT: Fixed a typo.

I recently had to sign someone s GPG key. I ve long used the caff tool from the signing-party package to help me with this. Unfortunately, I m using a new laptop and hadn t yet configured caff on it. Moreover, caff uses the system MTA by default, normally found at /usr/sbin/sendmail, and I hadn t yet properly configured it to send mail to the outside world. Since I have multiple email accounts and use mutt as my mail client, I use msmtp as my SMTP client / sendmail drop-in. This post describes how to configure caff to use msmtp. Reading the caff man page, one sees the following tantalising hint, which leads you to believe it s completely trivial to specify your own MTA:

$CONFIG 'mailer-send'  = [ 'sendmail', '-f', $CONFIG 'email' , '-it' ];

Unfortunately, substituting in a custom path, e.g., /home/rak/bin/msmtp/msmtp-default, for sendmail in the above line results in a long sequence of errors when caff tries to mail the signed keys:

Bareword "home" not allowed while "strict subs" in use at (eval 218) line 1.
Bareword "rak" not allowed while "strict subs" in use at (eval 218) line 1.
Bareword "bin" not allowed while "strict subs" in use at (eval 218) line 1.
Bareword "msmtp" not allowed while "strict subs" in use at (eval 218) line 1.
Bareword "msmtp" not allowed while "strict subs" in use at (eval 218) line 1.
Bareword "default" not allowed while "strict subs" in use at (eval 218) line 1.

Fortunately, it s still straightforward to accomplish after reading the perldoc for Mail::Mailer. In my case, it was sufficient to add the following to my ~/.caffrc:

$ENV 'PERL_MAILERS'  = 'sendmail:'.$ENV 'HOME' .'/bin/msmtp/msmtp-default';
$CONFIG 'mailer-send'  = [ 'sendmail' ];

To specify alternate paths to your sendmail-style MTA, simply modify the value of $ENV 'PERL_MAILERS' after the initial sendmail: bit. If you re using stock msmtp, I believe the following pair of lines will work, though I haven t tested it:

$ENV 'PERL_MAILERS'  = 'sendmail:/usr/bin/msmtp';
$CONFIG 'mailer-send'  = [ 'sendmail' ];

If there s a more elegant way to accomplish this, I d be happy to hear about it!

Since mid-2015 we were using the dep11-generator in Debian to build AppStream metadata about available software components in the distribution. Getting rid of dep11-generator Unfortunately, the old Python-based dep11-generator was hitting some hard limits pretty soon. For example, using multiprocessing with Python was a pain, since it resulted in some very hard-to-track bugs. Also, the multiprocessing approach (as opposed to multithreading) made it impossible to use the underlying LMDB database properly (it was basically closed and reopened in each forked off process, since pickling the Python LMDB object caused some really funny bugs, which usually manifested themselves in the application hanging forever without any information on what was going on). Additionally to that, the Python-based generator forced me to maintain two implementations of the AppStream YAML spec, one in C and one in Python, which consumes quite some time. There were also some other issues (e.g. no unit-tests) in the implementation, which made me think about rewriting the generator. Adventures in Go / Rust / D Since I didn t want to write this new piece of software in C (or basically, writing it in C was my last option

), I explored Go and Rust for this purpose and also did a small prototype in the D programming language, when I was starting to feel really adventurous. And while I never intended to write the new generator in D (I was pretty fixated on Go ), this is what happened. The strong points for D for this particular project were its close relation to C (and ease of using existing C code), its super-flat learning curve for someone who knows and likes C and C++ and its pretty powerful implementations of the concurrent and parallel programming paradigms. That being said, not all is great in D and there are some pretty dark spots too, mainly when it comes to the standard library and compilers. I will dive into my experiences with D in a separate blogpost. What good to expect from appstream-generator? So, what can the new appstream-generator do for you? Basically, the same as the old dep11-generator: It will extract metadata from a distribution s package archive, download and resize screenshots, search for icons and size them properly and generate reports in JSON and HTML of found metadata and issues. LibAppStream-based parsing, generation of YAML or XML, multi-distro support, As opposed to the old generator, the new generator utilizes the metadata parsers and writers of libappstream. This allows it to return the extracted metadata as AppStream YAML (for Debian) or XML (everyone else) It is also written in a distribution-agnostic way, so if someone wants to use it in a different distribution than Debian, this is possible now. It just requires a very small distribution-specific backend to be written, all of the details of the metadata extraction are abstracted away (just two interfaces need to be implemented). While I do not expect anyone except Debian to use this in the near future (most distros have found a solution to generate metadata already), the frontend-backend split is a much cleaner design than what was available in the previous code. It also allows to unit-test the code properly, without providing a Debian archive in the testsuite. Feature Flags, Optipng, The new generator also allows to enable and disable certain sets of features in a standardized way. E.g. Ubuntu uses a language-pack system for translations, which Debian doesn t use. Features like this can be implemented as disableable separate modules in the generator. We use this at time to e.g. allow descriptions from packages to be used as AppStream descriptions, or for running optipng on the generated PNG images and icons. No more Contents file dependency Another issue the old generator had was that it used the Contents file from the Debian archive to find matching icons for an application. We could never be sure whether the contents in the Contents file actually matched the contents of the package we were currently dealing with. What made things worse is that at Ubuntu, the archive software is only updating the Contents file ~~weekly~~ daily (while the generator might run multiple times a day), which has lead to software being ignored in the metadata, because icons could not yet be found. Even on Debian, with its quickly-updated Contents file, we could immediately see the effects of an out-of-date Contents file when updating it failed once. In the new generator, we read the contents of each package ourselves now and store them in a LMDB database, bypassing the Contents file and removing the whole class of problems resulting from missing or wrong contents-data. It can t all be good, right? That is true, there are also some known issues the new generator has: Large amounts of RAM required The better speed of the new generator comes at the cost of holding more stuff in RAM. Much more. When processing data from 5 architectures initially on Debian, the amount of required RAM might lie above 4GB, with the OOM killer sometimes being quicker than the garbage collector That being said, on subsequent runs the amount of required memory is much lower. Still, this is something I am working on to improve. What are symbolic links? To be faster, the appstream-generator will read the md5sum file in .deb packages instead of extracting the payload archive and reading its contents. Since the md5sums file does not list symbolic links, symlinks basically don t exist for the new generator. This is a problem for software symlinking icons or even .desktop files around, like e.g. LibreOffice does. I am still investigating how widespread the use of symlinks for icons and .desktop files is, but it looks like fixing packages (making them not-symlink stuff and rather move the files) might be the better approach than investing additional computing power to find symlinks or even switch back to parsing the Contents file. Input on this is welcome! Deploying asgen I finished the last pieces of the appstream-generator (together with doing lots of other cool things and talking to great people) at the GNOME Software Hackfest in London last week (detailed blogposts about things that happened there will follow many thanks once again for the Ubuntu community for sponsoring my attendance!). Since today, the new generator is running on the Debian infrastructure. If bigger issues are found, we can still roll back to the old code. I decided to deploy this faster, so we can get some good testing done before the Stretch release. Please report any issues you may find!

Search Results: "will"

24 April 2016

Bits from Debian: Debian welcomes its 2016 summer interns

Norbert Preining: Armenia and Turkey Erdo an did it again

Daniel Pocock: LinuxWochen, MiniDebConf Vienna and Linux Presentation Day

21 April 2016

John Goerzen: Count me as a systemd convert

20 April 2016

Jonathan Dowland: mount-on-demand backups

Ben Hutchings: Experiments with signed kernels and modules in Debian

Norbert Preining: GnuPG notes: subkeys, yubikey, gpg1 vs gpg2

19 April 2016

Dariusz Dwornikowski: HAProxy and 503 HTTP errors with AWS ELB as a backend

Rémi Vanicat: LudumDare35

18 April 2016

Reproducible builds folks: Reproducible builds: week 50 in Stretch cycle

Michael Prokop: Event: DebConf 16

Jonathan McDowell: Going to DebConf 16

Jonathan McDowell: Going to DebConf 16

Petter Reinholdtsen: NUUG contests Norwegian police DNS seizure of popcorn-time.no

Norbert Preining: TeX Live 2016 pretest and Debian packages

Matthew Garrett: One more attempt at SATA power management

17 April 2016

Sean Whitton: Mail expiring out of the postfix mail queue

16 April 2016

Scott Kitterman: Future of secure systems in the US

Ryan Kavanagh: Specifying a custom MTA path in caff

Matthias Klumpp: Introducing AppStream-Generator