Search Results: "ogi"

31 October 2023

Iustin Pop: Raspberry PI OS: upgrading and cross-grading

One of the downsides of running Raspberry PI OS is the fact that - not having the resources of pure Debian - upgrades are not recommended, and cross-grades (migrating between armhf and arm64) is not even mentioned. Is this really true? It is, after all a Debian-based system, so it should in theory be doable. Let s try!

Upgrading The recently announced release based on Debian Bookworm here says:
We have always said that for a major version upgrade, you should re-image your SD card and start again with a clean image. In the past, we have suggested procedures for updating an existing image to the new version, but always with the caveat that we do not recommend it, and you do this at your own risk. This time, because the changes to the underlying architecture are so significant, we are not suggesting any procedure for upgrading a Bullseye image to Bookworm; any attempt to do this will almost certainly end up with a non-booting desktop and data loss. The only way to get Bookworm is either to create an SD card using Raspberry Pi Imager, or to download and flash a Bookworm image from here with your tool of choice.
Which means, it s time to actually try it turns out it s actually trivial, if you use RPIs as headless servers. I had only three issues:
  • if using an initrd, the new initrd-building scripts/hooks are looking for some binaries in /usr/bin, and not in /bin; solution: install manually the usrmerge package, and then re-run dpkg --configure -a;
  • also if using an initrd, the scripts are looking for the kernel config file in /boot/config-$(uname -r), and the raspberry pi kernel package doesn t provide this; workaround: modprobe configs && zcat /proc/config.gz > /boot/config-$(uname -r);
  • and finally, on normal RPI systems, that don t use manual configurations of interfaces in /etc/network/interface, migrating from the previous dhcpcd to NetworkManager will break network connectivity, and require you to log in locally and fix things.
I expect most people to hit only the 3rd, and almost no-one to use initrd on raspberry pi. But, overall, aside from these two issues and a couple of cosmetic ones (login.defs being rewritten from scratch and showing a baffling diff, for example), it was easy. Is it worth doing? Definitely. Had no data loss, and no non-booting system.

Cross-grading (32 bit to 64 bit userland) This one is actually painful. Internet searches go from it s possible, I think to it s definitely not worth trying . Examples: Aside from these, there are a gazillion other posts about switching the kernel to 64 bit. And that s worth doing on its own, but it s only half the way. So, armed with two different systems - a RPI4 4GB and a RPI Zero W2 - I tried to do this. And while it can be done, it takes many hours - first system was about 6 hours, second the same, and a third RPI4 probably took ~3 hours only since I knew the problematic issues. So, what are the steps? Basically:
  • install devscripts, since you will need dget
  • enable new architecture in dpkg: dpkg --add-architecture arm64
  • switch over apt sources to include the 64 bit repos, which are different than the 32 bit ones (Raspberry PI OS did a migration here; normally a single repository has all architectures, of course)
  • downgrade all custom rpi packages/libraries to the standard bookworm/bullseye version, since dpkg won t usually allow a single library package to have different versions (I think it s possible to override, but I didn t bother)
  • install libc for the arm64 arch (this takes some effort, it s actually a set of 3-4 packages)
  • once the above is done, install whiptail:amd64 and rejoice at running a 64-bit binary!
  • then painfully go through sets of packages and migrate the set to arm64:
    • sometimes this work via apt, sometimes you ll need to use dget and dpkg -i
    • make sure you download both the armhf and arm64 versions before doing dpkg -i, since you ll need to rollback some installs
  • at one point, you ll be able to switch over dpkg and apt to arm64, at which point the default architecture flips over; from here, if you ve done it at the right moment, it becomes very easy; you ll probably need an apt install --fix-broken, though, at first
  • and then, finish by replacing all packages with arm64 versions
  • and then, dpkg --remove-architecture armhf, reboot, and profit!
But it s tears and blood to get to that point

Pain point 1: RPI custom versions of packages Since the 32bit armhf architecture is a bit weird - having many variations - it turns out that raspberry pi OS has many packages that are very slightly tweaked to disable a compilation flag or work around build/test failures, or whatnot. Since we talk here about 64-bit capable processors, almost none of these are needed, but they do make life harder since the 64 bit version doesn t have those overrides. So what is needed would be to say downgrade all armhf packages to the version in debian upstream repo , but I couldn t find the right apt pinning incantation to do that. So what I did was to remove the 32bit repos, then use apt-show-versions to see which packages have versions that are no longer in any repo, then downgrade them. There s a further, minor, complication that there were about 3-4 packages with same version but different hash (!), which simply needed apt install --reinstall, I think.

Pain point 2: architecture independent packages There is one very big issue with dpkg in all this story, and the one that makes things very problematic: while you can have a library package installed multiple times for different architectures, as the files live in different paths, a non-library package can only be installed once (usually). For binary packages (arch:any), that is fine. But architecture-independent packages (arch:all) are problematic since usually they depend on a binary package, but they always depend on the default architecture version! Hrmm, and I just realise I don t have logs from this, so I m only ~80% confident. But basically:
  • vim-solarized (arch:all) depends on vim (arch:any)
  • if you replace vim armhf with vim arm64, this will break vim-solarized, until the default architecture becomes arm64
So you need to keep track of which packages apt will de-install, for later re-installation. It is possible that Multi-Arch: foreign solves this, per the debian wiki which says:
Note that even though Architecture: all and Multi-Arch: foreign may look like similar concepts, they are not. The former means that the same binary package can be installed on different architectures. Yet, after installation such packages are treated as if they were native architecture (by definition the architecture of the dpkg package) packages. Thus Architecture: all packages cannot satisfy dependencies from other architectures without being marked Multi-Arch foreign.
It also has warnings about how to properly use this. But, in general, not many packages have it, so it is a problem.

Pain point 3: remove + install vs overwrite It seems that depending on how the solver computes a solution, when migrating a package from 32 to 64 bit, it can choose either to:
  • overwrite in place the package (akin to dpkg -i)
  • remove + install later
The former is OK, the later is not. Or, actually, it might be that apt never can do this, for example (edited for brevity):
# apt install systemd:arm64 --no-install-recommends
The following packages will be REMOVED:
  systemd
The following NEW packages will be installed:
  systemd:arm64
0 upgraded, 1 newly installed, 1 to remove and 35 not upgraded.
Do you want to continue? [Y/n] y
dpkg: systemd: dependency problems, but removing anyway as you requested:
 systemd-sysv depends on systemd.
Removing systemd (247.3-7+deb11u2) ...
systemd is the active init system, please switch to another before removing systemd.
dpkg: error processing package systemd (--remove):
 installed systemd package pre-removal script subprocess returned error exit status 1
dpkg: too many errors, stopping
Errors were encountered while processing:
 systemd
Processing was halted because there were too many errors.
But at the same time, overwrite in place is all good - via dpkg -i from /var/cache/apt/archives. In this case it manifested via a prerm script, in other cases is manifests via dependencies that are no longer satisfied for packages that can t be removed, etc. etc. So you will have to resort to dpkg -i a lot.

Pain point 4: lib- packages that are not lib During the whole process, it is very tempting to just go ahead and install the corresponding arm64 package for all armhf lib package, in one go, since these can coexist. Well, this simple plan is complicated by the fact that some packages are named libfoo-bar, but are actual holding (e.g.) the bar binary for the libfoo package. Examples:
  • libmagic-mgc contains /usr/lib/file/magic.mgc, which conflicts between the 32 and 64 bit versions; of course, it s the exact same file, so this should be an arch:all package, but
  • libpam-modules-bin and liblockfile-bin actually contain binaries (per the -bin suffix)
It s possible to work around all this, but it changes a 1 minute:
# apt install $(dpkg -i   grep ^ii   awk ' print $2 ' grep :amrhf sed -e 's/:armhf/:arm64')
into a 10-20 minutes fight with packages (like most other steps).

Is it worth doing? Compared to the simple bullseye bookworm upgrade, I m not sure about this. The result? Yes, definitely, the system feels - weirdly - much more responsive, logged in over SSH. I guess the arm64 base architecture has some more efficient ops than the lowest denominator armhf , so to say (e.g. there was in the 32 bit version some rpi-custom package with string ops), and thus migrating to 64 bit makes more things faster , but this is subjective so it might be actually not true. But from the point of view of the effort? Unless you like to play with dpkg and apt, and understand how these work and break, I d rather say, migrate to ansible and automate the deployment. It s doable, sure, and by the third system, I got this nailed down pretty well, but it was a lot of time spent. The good aspect is that I did 3 migrations:
  • rpi zero w2: bullseye 32 bit to 64 bit, then bullseye to bookworm
  • rpi 4: bullseye to bookworm, then bookworm 32bit to 64 bit
  • same, again, for a more important system
And all three worked well and no data loss. But I m really glad I have this behind me, I probably wouldn t do a fourth system, even if forced And now, waiting for the RPI 5 to be available See you!

Russell Coker: Links October 2023

The Daily Kos has an interesting article about a new more effective method of desalination [1]. Here is a video of a crazy guy zapping things with 100 car batteries [2]. This is sonmething you should avoid if you want to die of natural causes. Does dying while making a science video count for a Darwin Award? A Hacker News comment has an interesting explanation of Unix signals [3]. Interesting documentary on the rise of mega corporations [4]. We need to split up Google, Facebook, and Amazon ASAP. Also every phone platform should have competing app stores. Dave Taht gave an interesting LCA lecture about Internet congestion control [5]. He also referenced a web site about projects to alleviate the buffer bloat problem [6]. This tiny event based sensor is an interesting product [7]. It could lead to some interesting (but possibly invasive) technological developments in phones. Tara Barnett s Everything Open lecture Swiss Army GLAM had some interesting ideas for community software development [8]. Having lots of small programs communicating with APIs is an interesting way to get people into development. Actually Hardcore Overclocking has an interesting youtube video about the differences between x8 and x14 DDR4 DIMMs [9]. Interesting YouTube video from someone who helped the Kurds defend against Turkey about how war tunnels work [10]. He makes a strong case that the Israeli invasion of the Gaza Strip won t be easy or pleasant.

22 October 2023

Jamie McClelland: Users without passwords

About fifteen years ago, while debugging a database probem, I was horrified to discover that we had two root users - one with the password I had been using and one without a password. Nooo! So, I wrote a simple maintenance script that searched for and deleted any user in our database without a password. I even made it part of our puppet recipe - since the database server was in use by users and I didn t want anyone using SQL statements to change their password to an empty value. Then I forgot about it. Recently, I upgraded our MariaDB databases to Debian bullseye, which inserted the mariadb.sys user which . doesn t have a password set. It seems to be locked down in other ways, but my dumb script didn t know about that and happily deleted the user. Who needs that mariadb.sys user anyway? Apparently we all do. On one server, I can t login as root anymore. On another server I can login as root, but if I try to list users I get an error:
ERROR 1449 (HY000): The user specified as a definer ( mariadb.sys @ localhost ) does not exist
The Internt is full of useless advice. The most common is to simply insert that user. Except
MariaDB [mysql]> CREATE USER  mariadb.sys @ localhost  ACCOUNT LOCK PASSWORD EXPIRE;
ERROR 1396 (HY000): Operation CREATE USER failed for 'mariadb.sys'@'localhost'
MariaDB [mysql]> 
Yeah, that s not going to work. It seems like we are dealing with two changes. One, the old mysql.user table was replaced by the global_priv table and then turned into a view for backwards compatibility. And two, for sensible reasons the default definer for this view has been changed from the root user to a user that, ahem, is unlikely to be changed or deleted. Apparently I can t add the mariadb.sys user because it would alter the user view which has a definer that doesn t exist. Although not sure if this really is the reason? Fortunately, I found an excellent suggestion for changing the definer of a view. My modified version of the answer is, run the following command which will generate a SQL statement:
SELECT CONCAT("ALTER DEFINER=root@localhost VIEW ", table_name, " AS ", view_definition, ";") FROM information_schema.views WHERE table_schema='mysql' AND definer = 'mariadb.sys@localhost';
Then, execute the statement. And then also update the mysql.proc table:
UPDATE mysql.proc SET definer = 'root@localhost' WHERE definer = 'mariadb.sys@localhost';
And lastly, I had to run:
DELETE FROM tables_priv WHERE User = 'mariadb.sys';
FLUSH privileges;
Wait, was the tables_priv entry the whole problem all along? Not sure. But now I can run:
CREATE USER  mariadb.sys @ localhost  ACCOUNT LOCK PASSWORD EXPIRE;
GRANT SELECT, DELETE ON  mysql . global_priv  TO  mariadb.sys @ localhost ;
And reverse the other statements:
SELECT CONCAT("ALTER DEFINER= mariadb.sys @localhost VIEW ", table_name, " AS ", view_definition, ";") FROM information_schema.views WHERE table_schema='mysql' AND definer = 'root@localhost';
[Execute the output.]
UPDATE mysql.proc SET definer = 'mariadb.sys@localhost' WHERE definer = 'root@localhost';
And while we re on the topic of borked MariaDB authentication, here are the steps to change the root password and restore all root privielges if you can t get in at all or your root user is missing the GRANT OPTION (you can change ALTER to CREATE if the root user does not even exist):
systemctl stop mariadb
mariadbd-safe --skip-grant-tables --skip-networking &
mysql -u root
[mysql]> FLUSH PRIVILEGES
[mysql]> ALTER USER  root @ localhost  IDENTIFIED VIA mysql_native_password USING PASSWORD('your-secret-password') OR unix_socket; 
[mysql]> GRANT ALL PRIVILEGES ON *.* to 'root'@'localhost' WITH GRANT OPTION;
mariadbd-admin shutdown
systemctl start mariadb

14 October 2023

Fran ois Marier: Enabling AppArmor on a Linode VPS in enforcement mode

Enabling AppArmor on a Debian Linode VPS is not entirely straightforward. Here's what I had to do in order to make it work.

Packages to install The easy bit was to install a few packages:
apt install grub2 apparmor-profiles-extra apparmor-profiles apparmor
and then adding apparmor=1 security=apparmor to the kernel command line (GRUB_CMDLINE_LINUX) in /etc/default/grub.

Move away from using Linode's kernels As mentioned in this blog post, I found out that these parameters are ignored by the Linode kernels. I had to:
  1. login to the Linode Manager (i.e. https://cloud.linode.com/linodes/<linode ID>/configurations),
  2. click the node relevant node,
  3. click "Edit" next to the configuration profile, and
  4. change the kernel to "GRUB 2".

Fix grub Next I found out that grub doesn't actually install itself properly because it can't be installed directly on the virtual drives provided by Linode (KVM). Manually running this hack worked for me:
grub-install --grub-setup=/bin/true /dev/null

Unbound + Let's Encrypt fix Finally, my local Unbound installation stopped working because it couldn't access the Let's Encrypt certificates anymore. The solution to this was pretty straightforward. All I needed to do was to add the following to /etc/apparmor.d/local/usr.sbin.unbound:
/etc/letsencrypt/archive/** r,
/etc/letsencrypt/live/** r,

12 October 2023

Jonathan McDowell: Installing Debian on the BananaPi M2 Zero

My previously mentioned C.H.I.P. repurposing has been partly successful; I ve found a use for it (which I still need to write up), but unfortunately it s too useful and the fact it s still a bit flaky has become a problem. I spent a while trying to isolate exactly what the problem is (I m still seeing occasional hard hangs with no obvious debug output in the logs or on the serial console), then realised I should just buy one of the cheap ARM SBC boards currently available. The C.H.I.P. is based on an Allwinner R8, which is a single ARM v7 core (an A8). So it s fairly low power by today s standards and it seemed pretty much any board would probably do. I considered a Pi 2 Zero, but couldn t be bothered trying to find one in stock at a reasonable price (I ve had one on backorder from CPC since May 2022, and yes, I know other places have had them in stock since but I don t need one enough to chase and I m now mostly curious about whether it will ever ship). As the title of this post gives away, I settled on a Banana Pi BPI-M2 Zero, which is based on an Allwinner H3. That s a quad-core ARM v7 (an A7), so a bit more oompfh than the C.H.I.P. All in all it set me back 25, including a set of heatsinks that form a case around it. I started with the vendor provided Debian SD card image, which is based on Debian 9 (stretch) and so somewhat old. I was able to dist-upgrade my way through buster and bullseye, and end up on bookworm. I then discovered the bookworm 6.1 kernel worked just fine out of the box, and even included a suitable DTB. Which got me thinking about whether I could do a completely fresh Debian install with minimal tweaking. First thing, a boot loader. The Allwinner chips are nice in that they ll boot off SD, so I just needed a suitable u-boot image. Rather than go with the vendor image I had a look at mainline and discovered it had support! So let s build a clean image:
noodles@buildhost:~$ mkdir ~/BPI
noodles@buildhost:~$ cd ~/BPI
noodles@buildhost:~/BPI$ ls
noodles@buildhost:~/BPI$ git clone https://source.denx.de/u-boot/u-boot.git
Cloning into 'u-boot'...
remote: Enumerating objects: 935825, done.
remote: Counting objects: 100% (5777/5777), done.
remote: Compressing objects: 100% (1967/1967), done.
remote: Total 935825 (delta 3799), reused 5716 (delta 3769), pack-reused 930048
Receiving objects: 100% (935825/935825), 186.15 MiB   2.21 MiB/s, done.
Resolving deltas: 100% (785671/785671), done.
noodles@buildhost:~/BPI$ mkdir u-boot-build
noodles@buildhost:~/BPI$ cd u-boot
noodles@buildhost:~/BPI/u-boot$ git checkout v2023.07.02
...
HEAD is now at 83cdab8b2c Prepare v2023.07.02
noodles@buildhost:~/BPI/u-boot$ make O=../u-boot-build bananapi_m2_zero_defconfig
  HOSTCC  scripts/basic/fixdep
  GEN     Makefile
  HOSTCC  scripts/kconfig/conf.o
  YACC    scripts/kconfig/zconf.tab.c
  LEX     scripts/kconfig/zconf.lex.c
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/conf
#
# configuration written to .config
#
make[1]: Leaving directory '/home/noodles/BPI/u-boot-build'
noodles@buildhost:~/BPI/u-boot$ cd ../u-boot-build/
noodles@buildhost:~/BPI/u-boot-build$ make CROSS_COMPILE=arm-linux-gnueabihf-
  GEN     Makefile
scripts/kconfig/conf  --syncconfig Kconfig
...
  LD      spl/u-boot-spl
  OBJCOPY spl/u-boot-spl-nodtb.bin
  COPY    spl/u-boot-spl.bin
  SYM     spl/u-boot-spl.sym
  MKIMAGE spl/sunxi-spl.bin
  MKIMAGE u-boot.img
  COPY    u-boot.dtb
  MKIMAGE u-boot-dtb.img
  BINMAN  .binman_stamp
  OFCHK   .config
noodles@buildhost:~/BPI/u-boot-build$ ls -l u-boot-sunxi-with-spl.bin
-rw-r--r-- 1 noodles noodles 494900 Aug  8 08:06 u-boot-sunxi-with-spl.bin
I had the advantage here of already having a host setup to cross build armhf binaries, but this was all done on a Debian bookworm host with packages from main. I ve put my build up here in case it s useful to someone - everything else below can be done on a normal x86_64 host. Next I needed a Debian installer. I went for the netboot variant - although I was writing it to SD rather than TFTP booting I wanted as much as possible to come over the network.
noodles@buildhost:~/BPI$ wget https://deb.debian.org/debian/dists/bookworm/main/installer-armhf/20230607%2Bdeb12u1/images/netboot/netboot.tar.gz
...
2023-08-08 10:15:03 (34.5 MB/s) -  netboot.tar.gz  saved [37851404/37851404]
noodles@buildhost:~/BPI$ tar -axf netboot.tar.gz
Then I took a suitable microSD card and set it up with a 500M primary VFAT partition, leaving the rest for Linux proper. I could have got away with a smaller VFAT partition but I d initially thought I might need to put some more installation files on it.
noodles@buildhost:~/BPI$ sudo fdisk /dev/sdb
Welcome to fdisk (util-linux 2.38.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): o
Created a new DOS (MBR) disklabel with disk identifier 0x793729b3.
Command (m for help): n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p):
Using default response p.
Partition number (1-4, default 1):
First sector (2048-60440575, default 2048):
Last sector, +/-sectors or +/-size K,M,G,T,P  (2048-60440575, default 60440575): +500M
Created a new partition 1 of type 'Linux' and of size 500 MiB.
Command (m for help): t
Selected partition 1
Hex code or alias (type L to list all): c
Changed type of partition 'Linux' to 'W95 FAT32 (LBA)'.
Command (m for help): n
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p):
Using default response p.
Partition number (2-4, default 2):
First sector (1026048-60440575, default 1026048):
Last sector, +/-sectors or +/-size K,M,G,T,P  (534528-60440575, default 60440575):
Created a new partition 2 of type 'Linux' and of size 28.3 GiB.
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
$ sudo mkfs -t vfat -n BPI-UBOOT /dev/sdb1
mkfs.fat 4.2 (2021-01-31)
The bootloader image gets written 8k into the SD card (our first partition starts at sector 2048, i.e. 1M into the device, so there s plenty of space here):
noodles@buildhost:~/BPI$ sudo dd if=u-boot-build/u-boot-sunxi-with-spl.bin of=/dev/sdb bs=1024 seek=8
483+1 records in
483+1 records out
494900 bytes (495 kB, 483 KiB) copied, 0.0282234 s, 17.5 MB/s
Copy the Debian installer files onto the VFAT partition:
noodles@buildhost:~/BPI$ cp -r debian-installer/ /media/noodles/BPI-UBOOT/
Unmount the SD from the build host, pop it into the M2 Zero, boot it up while connected to the serial console, hit a key to stop autoboot and tell it to boot the installer:
U-Boot SPL 2023.07.02 (Aug 08 2023 - 09:05:44 +0100)
DRAM: 512 MiB
Trying to boot from MMC1
U-Boot 2023.07.02 (Aug 08 2023 - 09:05:44 +0100) Allwinner Technology
CPU:   Allwinner H3 (SUN8I 1680)
Model: Banana Pi BPI-M2-Zero
DRAM:  512 MiB
Core:  60 devices, 17 uclasses, devicetree: separate
WDT:   Not starting watchdog@1c20ca0
MMC:   mmc@1c0f000: 0, mmc@1c10000: 1
Loading Environment from FAT... Unable to read "uboot.env" from mmc0:1...
In:    serial
Out:   serial
Err:   serial
Net:   No ethernet found.
Hit any key to stop autoboot:  0
=> setenv dibase /debian-installer/armhf
=> fatload mmc 0:1 $ kernel_addr_r  $ dibase /vmlinuz
5333504 bytes read in 225 ms (22.6 MiB/s)
=> setenv bootargs "console=ttyS0,115200n8"
=> fatload mmc 0:1 $ fdt_addr_r  $ dibase /dtbs/sun8i-h2-plus-bananapi-m2-zero.dtb
25254 bytes read in 7 ms (3.4 MiB/s)
=> fdt addr $ fdt_addr_r  0x40000
Working FDT set to 43000000
=> fatload mmc 0:1 $ ramdisk_addr_r  $ dibase /initrd.gz
31693887 bytes read in 1312 ms (23 MiB/s)
=> bootz $ kernel_addr_r  $ ramdisk_addr_r :$ filesize  $ fdt_addr_r 
Kernel image @ 0x42000000 [ 0x000000 - 0x516200 ]
## Flattened Device Tree blob at 43000000
   Booting using the fdt blob at 0x43000000
Working FDT set to 43000000
   Loading Ramdisk to 481c6000, end 49fffc3f ... OK
   Loading Device Tree to 48183000, end 481c5fff ... OK
Working FDT set to 48183000
Starting kernel ...
At this point the installer runs and you can do a normal install. Well, except the wifi wasn t detected, I think because the netinst images don t include firmware. I spent a bit of time trying to figure out how to include it but ultimately ended up installing over a USB ethernet dongle, which Just Worked and was less faff. Installing firmware-brcm80211 once installation completed allowed the built-in wifi to work fine. After install you need to configure u-boot to boot without intervention. At the u-boot prompt (i.e. after hitting a key to stop autoboot):
=> setenv bootargs "console=ttyS0,115200n8 root=LABEL=BPI-ROOT ro"
=> setenv bootcmd 'ext4load mmc 0:2 $ fdt_addr_r  /boot/sun8i-h2-plus-bananapi-m2-zero.dtb ; fdt addr $ fdt_addr_r  0x40000 ; ext4load mmc 0:2 $ kernel_addr_r  /boot/vmlinuz ; ext4load mmc 0:2 $ ramdisk_addr_r  /boot/initrd.img ; bootz $ kernel_addr_r  $ ramdisk_addr_r :$ filesize  $ fdt_addr_r '
=> saveenv
Saving Environment to FAT... OK
=> reset
This is assuming you have /boot on partition 2 on the SD - I left the first partition as VFAT (that s where the u-boot environment will be saved) and just used all of the rest as a single ext4 partition. I did have to do an e2label /dev/sdb2 BPI-ROOT to label / appropriately; otherwise I occasionally saw the SD card appear as mmc1 for Linux (I m guessing due to asynchronous boot order with the wifi). You should now find the device boots without intervention.

Reproducible Builds: Reproducible Builds in September 2023

Welcome to the September 2023 report from the Reproducible Builds project In these reports, we outline the most important things that we have been up to over the past month. As a quick recap, whilst anyone may inspect the source code of free software for malicious flaws, almost all software is distributed to end users as pre-compiled binaries.
Andreas Herrmann gave a talk at All Systems Go 2023 titled Fast, correct, reproducible builds with Nix and Bazel . Quoting from the talk description:

You will be introduced to Google s open source build system Bazel, and will learn how it provides fast builds, how correctness and reproducibility is relevant, and how Bazel tries to ensure correctness. But, we will also see where Bazel falls short in ensuring correctness and reproducibility. You will [also] learn about the purely functional package manager Nix and how it approaches correctness and build isolation. And we will see where Bazel has an advantage over Nix when it comes to providing fast feedback during development.
Andreas also shows how you can get the best of both worlds and combine Nix and Bazel, too. A video of the talk is available.
diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb fixed compatibility with file(1) version 5.45 [ ] and updated some documentation [ ]. In addition, Vagrant Cascadian extended support for GNU Guix [ ][ ] and updated the version in that distribution as well. [ ].
Yet another reminder that our upcoming Reproducible Builds Summit is set to take place from October 31st November 2nd 2023 in Hamburg, Germany. If you haven t been before, our summits are a unique gathering that brings together attendees from diverse projects, united by a shared vision of advancing the Reproducible Builds effort. During this enriching event, participants will have the opportunity to engage in discussions, establish connections and exchange ideas to drive progress in this vital field. If you re interested in joining us this year, please make sure to read the event page, the news item, or the invitation email that Mattia Rizzolo sent out recently, all of which have more details about the event and location. We are also still looking for sponsors to support the event, so please reach out to the organising team if you are able to help. Also note that PackagingCon 2023 is taking place in Berlin just before our summit.
On the Reproducible Builds website, Greg Chabala updated the JVM-related documentation to update a link to the BUILDSPEC.md file. [ ] And Fay Stegerman fixed the builds failing because of a YAML syntax error.

Distribution work In Debian, this month: September saw F-Droid add ten new reproducible apps, and one existing app switched to reproducible builds. In addition, two reproducible apps were archived and one was disabled for a current total of 199 apps published with Reproducible Builds and using the upstream developer s signature. [ ] In addition, an extensive blog post was posted on f-droid.org titled Reproducible builds, signing keys, and binary repos .

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of such patches, including:

Testing framework The Reproducible Builds project operates a comprehensive testing framework (available at tests.reproducible-builds.org) in order to check packages and other artifacts for reproducibility. In August, a number of changes were made by Holger Levsen:
  • Disable armhf and i386 builds due to Debian bug #1052257. [ ][ ][ ][ ]
  • Run diffoscope with a lower ionice priority. [ ]
  • Log every build in a simple text file [ ] and create persistent stamp files when running diffoscope to ease debugging [ ].
  • Run schedulers one hour after dinstall again. [ ]
  • Temporarily use diffoscope from the host, and not from a schroot running the tested suite. [ ][ ]
  • Fail the diffoscope distribution test if the diffoscope version cannot be determined. [ ]
  • Fix a spelling error in the email to IRC gateway. [ ]
  • Force (and document) the reconfiguration of all jobs, due to the recent rise of zombies. [ ][ ][ ][ ]
  • Deal with a rare condition when killing processes which should not be there. [ ]
  • Install the Debian backports kernel in an attempt to address Debian bug #1052257. [ ][ ]
In addition, Mattia Rizzolo fixed a call to diffoscope --version (as suggested by Fay Stegerman on our mailing list) [ ], worked on an openQA credential issue [ ] and also made some changes to the machine-readable reproducible metadata, reproducible-tracker.json [ ]. Lastly, Roland Clobus added instructions for manual configuration of the openQA secrets [ ].

If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

11 October 2023

Russell Coker: PinePhone Status

4 months ago I got my PinePhonePro [1]. Since then I have got SE Linux working on it to the stage of allowing it to boot correctly with Debian/Unstable, login with the user_t domain (minimum privilege for the graphical user) and make and receive calls. I finished getting SE Linux working reasonably well 3 days ago and most (but not all) of the SE Linux policy is in Debian now. I ve been getting good at Github PRs and I m sending a lot of policy upstream, so the next version of Debian will have a much smaller diff from the upstream Refpolicy. I have been running the PinePhone with Plasma Mobile because I prefer KDE, I would run GNOME/Phoc if it gave significantly better functionality. 3 days ago I moved my main SIM (the one with the number that people call about work etc) to my PinePhone and tried running it as my main phone. Today I gave up on that. My Android History The last phone I had that did everything I needed was a Huawei Mate 10 Pro that I bought refurbished in June 2019 for $389. The Mate 10 Pro runs Android with the Google Play store and has been quite unremarkable which is presumably why I forgot to blog about it when I got it, it was a slight upgrade over the Huawei Mate 9 [2] that I had used for 2 years before that. In April 2022 I tried using a Huawei Nova 7i as my main phone without Google Play programs or services [3]. That experiment was a failure as I couldn t get NextCloud to work for Calendaring and Contacts. It could be that I stuffed something up when trying that, but I put more skill and effort into trying to get it to work than most people ever would. The Nova 7i is a very slick phone, faster and nicer than the Mate 10 Pro (as expected being 2 years newer) while also having ridiculously long battery life. The Nova 7i when always on running the SchildiChat Matrix client and the Conversations Jabber client it will use less than 10% battery in a 8 hour work day. As nice as the Nova 7i is for the core functions I still need to have Play Store apps for LinkedIn, Twitter, Facebook, Zoom, etc. Which meant connecting the Mate 10 Pro via Wifi. As slick as the Nova 7i is for non-Google stuff running it and the Mate 10 Pro is a medium amount of pain for a small amount of freedom. So now I have for the moment abandoned the Nova 7i and gone back to the Mate 10 Pro. What I will try to do is to either forcibly install Google Play on the Nova 7i to make it my proprietary phone or to install an open distribution of Linux (IE not Android) to make it at least a small tablet which incidentally is much more powerful than a PinePhonePro. Issues With the PinePhonePro The battery charges very slowly (as much as 50 hours estimated charge time) and discharges fast. When used in a typical way in Caffeine mode to stop suspend so I can ssh to it etc it won t come close to lasting an 8 hour day. Also it will only take 5V charging and ideally wants 5V 3A charging which most chargers won t do. The charging speed over regular USB ports is very slow, sometimes stating it will take as much as 50 hours to charge. A phone that gets below 50% charge in less than 4 hours and can t be charged at a reasonable speed from a USB port on a laptop or monitor is going to be a major pain to use in the office. I don t think this can be fixed in software, we can alleviate it by making software more CPU efficient and by enabling various hardware sleep modes more effectively but the slow charging is a hardware issue that can t be fixed. The phone call quality is poor. Usually when on a call I hear static and sometimes the person at the other end appears to hear nothing. Also the UI for calls is different from Android which makes it take longer to answer a call and gives more missed calls. The UI issue is a combination of software and habits, both of which can be changed. But the call quality may be a hardware issue. I don t know if it s a hardware issue specific to my phone or something related to the PinePhonePro on the Telstra network. Clicking on notification in the drop-down doesn t take me to the app. I don t know if this is regarded as a bug by the Plasma-Mobile developers. Also notifications aren t displayed on the lock screen and there doesn t seem to be a configuration option to enable this. The Plasma-Mobile configuration for the wifi hotspot is difficult. There is no button for it in the drop-down menu (called Quicksettings in Plasma-Mobile) and no way of easily determining whether it s in hotspot or wifi client mode. This isn t an insurmountable problem and the worst-case is that I could write a script to do it, but it s still annoying. There is apparent support in the desktop version of KDE for syncing contacts from Google and I could probably get that working (although I failed last time I tried on the desktop), but it is a pain. Conclusion Most of the problems are software related and therefore I can get involved in solving them. I plan to keep working on these things. If all the software had worked in an ideal manner then I would have spent more time investigating the hardware issues of battery life and charge time and the quality of calls. I now have my Librem5 [4] running Debian so I will be able to compare call quality with the PinePhonePro. If I m unable to get the PinePhonePro working adequately then maybe making the Librem5 my main phone will be an option. I hope that by early next year I will be able to make another test at using a FOSS phone my main phone. In the mean time I can still work on convergence and other things.

10 October 2023

Matthias Klumpp: How to indicate device compatibility for your app in MetaInfo data

At the moment I am hard at work putting together the final bits for the AppStream 1.0 release (hopefully to be released this month). The new release comes with many new new features, an improved developer API and removal of most deprecated things (so it carefully breaks compatibility with very old data and the previous C API). One of the tasks for the upcoming 1.0 release was #481 asking about a formal way to distinguish Linux phone applications from desktop applications. AppStream infamously does not support any is-for-phone label for software components, instead the decision whether something is compatible with a device is based the the device s capabilities and the component s requirements. This allows for truly adaptive applications to describe their requirements correctly, and does not lock us into form factors going into the future, as there are many and the feature range between a phone, a tablet and a tiny laptop is quite fluid. Of course the match to current device capabilities check does not work if you are a website ranking phone compatibility. It also does not really work if you are a developer and want to know which devices your component / application will actually be considered compatible with. One goal for AppStream 1.0 is to have its library provide more complete building blocks to software centers. Instead of just a here s the data, interpret it according to the specification API, libappstream now interprets the specification for the application and provides API to handle most common operations like checking device compatibility. For developers, AppStream also now implements a few virtual chassis configurations , to roughly gauge which configurations a component may be compatible with. To test the new code, I ran it against the large Debian and Flatpak repositories to check which applications are considered compatible with what chassis/device type already. The result was fairly disastrous, with many applications not specifying compatibility correctly (many do, but it s by far not the norm!). Which brings me to the actual topic of this blog post: Very few seem to really know how to mark an application compatible with certain screen sizes and inputs! This is most certainly a matter of incomplete guides and good templates, so maybe this post can help with that a bit:

The ultimate cheat-sheet to mark your app chassis-type compatible As a quick reminder, compatibility is indicated using AppStream s relations system: A requires relation indicates that the system will not run at all or will run terribly if the requirement is not met. If the requirement is not met, it should not be installable on a system. A recommends relation means that it would be advantageous to have the recommended items, but it s not essential to run the application (it may run with a degraded experience without the recommended things though). And a supports relation means a given interface/device/control/etc. is supported by this application, but the application may work completely fine without it.

I have a desktop-only application A desktop-only application is characterized by needing a larger screen to fit the application, and requiring a physical keyboard and accurate mouse input. This type is assumed by default if no capabilities are set for an application, but it s better to be explicit. This is the metadata you need:
<component type="desktop-application">
  <id>org.example.desktopapp</id>
  <name>DesktopApp</name>
  [...]
  <requires>
    <display_length>768</display_length>
    <control>keyboard</control>
    <control>pointing</control>
  </requires>
  [...]
</component>
With this requires relation, you require a small-desktop sized screen (at least 768 device-independent pixels (dp) on its smallest edge) and require a keyboard and mouse to be present / connectable. Of course, if your application needs more minimum space, adjust the requirement accordingly. Note that if the requirement is not met, your application may not be offered for installation.
Note: Device-independent / logical pixels One logical pixel (= device independent pixel) roughly corresponds to the visual angle of one pixel on a device with a pixel density of 96 dpi (for historical X11 reasons) and a distance from the observer of about 52 cm, making the physical pixel about 0.26 mm in size. When using logical pixels as unit, they might not always map to exact physical lengths as their exact size is defined by the device providing the display. They do however accurately depict the maximum amount of pixels that can be drawn in the depicted direction on the device s display space. AppStream always uses logical pixels when measuring lengths in pixels.

I have an application that works on mobile and on desktop / an adaptive app Adaptive applications have fewer hard requirements, but a wide range of support for controls and screen sizes. For example, they support touch input, unlike desktop apps. An example MetaInfo snippet for these kind of apps may look like this:
<component type="desktop-application">
  <id>org.example.adaptive_app</id>
  <name>AdaptiveApp</name>
  [...]
  <requires>
    <display_length>360</display_length>
  </requires>
  <supports>
    <control>keyboard</control>
    <control>pointing</control>
    <control>touch</control>
  </supports>
  [...]
</component>
Unlike the pure desktop application, this adaptive application requires a much smaller lowest display edge length, and also supports touch input, in addition to keyboard and mouse/touchpad precision input.

I have a pure phone/table app Making an application a pure phone application is tricky: We need to mark it as compatible with phones only, while not completely preventing its installation on non-phone devices (even though its UI is horrible, you may want to test the app, and software centers may allow its installation when requested explicitly even if they don t show it by default). This is how to achieve that result:
<component type="desktop-application">
  <id>org.example.phoneapp</id>
  <name>PhoneApp</name>
  [...]
  <requires>
    <display_length>360</display_length>
  </requires>
  <recommends>
    <display_length compare="lt">1280</display_length>
    <control>touch</control>
  </recommends>
  [...]
</component>
We require a phone-sized display minimum edge size (adjust to a value that is fit for your app!), but then also recommend the screen to have a smaller edge size than a larger tablet/laptop, while also recommending touch input and not listing any support for keyboard and mouse. Please note that this blog post is of course not a comprehensive guide, so if you want to dive deeper into what you can do with requires/recommends/suggests/supports, you may want to have a look at the relations tags described in the AppStream specification.

Validation It is still easy to make mistakes with the system requirements metadata, which is why AppStream 1.0 will provide more commands to check MetaInfo files for system compatibility. Current pre-1.0 AppStream versions already have an is-satisfied command to check if the application is compatible with the currently running operating system:
:~$ appstreamcli is-satisfied ./org.example.adaptive_app.metainfo.xml
Relation check for: */*/*/org.example.adaptive_app/*
Requirements:
   Unable to check display size: Can not read information without GUI toolkit access.
Recommendations:
   No recommended items are set for this software.
Supported:
   Physical keyboard found.
   Pointing device (e.g. a mouse or touchpad) found.
   This software supports touch input.
In addition to this command, AppStream 1.0 will introduce a new one as well: check-syscompat. This command will check the component against libappstream s mock system configurations that define a most common (whatever that is at the time) configuration for a respective chassis type. If you pass the --details flag, you can even get an explanation why the component was considered or not considered for a specific chassis type:
:~$ appstreamcli check-syscompat --details ./org.example.phoneapp.metainfo.xml
Chassis compatibility check for: */*/*/org.example.phoneapp/*
Desktop:
   Incompatible
   recommends: This software recommends a display with its shortest edge
   being << 1280 px in size, but the display of this device has 1280 px.
   recommends: This software recommends a touch input device.
Laptop:
   Incompatible
   recommends: This software recommends a display with its shortest edge 
   being << 1280 px in size, but the display of this device has 1280 px.
   recommends: This software recommends a touch input device.
Server:
   Incompatible
   requires: This software needs a display for graphical content.
   recommends: This software needs a display for graphical content.
   recommends: This software recommends a touch input device.
Tablet:
   Compatible (100%)
Handset:
   Compatible (100%)
I hope this is helpful for people. Happy metadata writing!

6 October 2023

Russ Allbery: Review: The Far Reaches

Review: The Far Reaches, edited by John Joseph Adams
Publisher: Amazon Original Stories
Copyright: June 2023
ISBN: 1-6625-1572-3
ISBN: 1-6625-1622-3
ISBN: 1-6625-1503-0
ISBN: 1-6625-1567-7
ISBN: 1-6625-1678-9
ISBN: 1-6625-1533-2
Format: Kindle
Pages: 219
Amazon has been releasing anthologies of original short SFF with various guest editors, free for Amazon Prime members. I previously tried Black Stars (edited by Nisi Shawl and Latoya Peterson) and Forward (edited by Blake Crouch). Neither were that good, but the second was much worse than the first. Amazon recently released a new collection, this time edited by long-standing SFF anthology editor John Joseph Adams and featuring a new story by Ann Leckie, which sounded promising enough to give them another chance. The definition of insanity is doing the same thing over and over again and expecting different results. As with the previous anthologies, each story is available separately for purchase or Amazon Prime "borrowing" with separate ISBNs. The sidebar cover is for the first in the sequence. Unlike the previous collections, which were longer novelettes or novellas, my guess is all of these are in the novelette range. (I did not do a word count.) If you're considering this anthology, read the Okorafor story ("Just Out of Jupiter's Reach"), consider "How It Unfolds" by James S.A. Corey, and avoid the rest. "How It Unfolds" by James S.A. Corey: Humans have invented a new form of physics called "slow light," which can duplicate any object that is scanned. The energy expense is extremely high, so the result is not a post-scarcity paradise. What the technology does offer, however, is a possible route to interstellar colonization: duplicate a team of volunteers and a ship full of bootstrapping equipment, and send copies to a bunch of promising-looking exoplanets. One of them might succeed. The premise is interesting. The twists Corey adds on top are even better. What can be duplicated once can be duplicated again, perhaps with more information. This is a lovely science fiction idea story that unfortunately bogs down because the authors couldn't think of anywhere better to go with it than relationship drama. I found the focus annoying, but the ideas are still very neat. (7) "Void" by Veronica Roth: A maintenance worker on a slower-than-light passenger ship making the run between Sol and Centauri unexpectedly is called to handle a dead body. A passenger has been murdered, two days outside the Sol system. Ace is in no way qualified to investigate the murder, nor is it her job, but she's watched a lot of crime dramas and she has met the victim before. The temptation to start poking around is impossible to resist. It's been a long time since I've read a story built around the differing experiences of time for people who stay on planets and people who spend most of their time traveling at relativistic speeds. It's a bit of a retro idea from an earlier era of science fiction, but it's still a good story hook for a murder mystery. None of the characters are that memorable and Roth never got me fully invested in the story, but this was still a pleasant way to pass the time. (6) "Falling Bodies" by Rebecca Roanhorse: Ira is the adopted son of a Genteel senator. He was a social experiment in civilizing the humans: rescue a human orphan and give him the best of Genteel society to see if he could behave himself appropriately. The answer was no, which is how Ira finds himself on Long Reach Station with a parole officer and a schooling opportunity, hopefully far enough from his previous mistakes for a second chance. Everyone else seems to like Rebecca Roanhorse's writing better than I do, and this is no exception. Beneath the veneer of a coming-of-age story with a twist of political intrigue, this is brutal, depressing, and awful, with an ending that needs a lot of content warnings. I'm sorry that I read it. (3) "The Long Game" by Ann Leckie: The Imperial Radch trilogy are some of my favorite science fiction novels of all time, but I am finding Leckie's other work a bit hit and miss. I have yet to read a novel of hers that I didn't like, but the short fiction I've read leans more heavily into exploring weird and alien perspectives, which is not my favorite part of her work. This story is firmly in that category: the first-person protagonist is a small tentacled alien creature, a bit like a swamp-dwelling octopus. I think I see what Leckie is doing here: balancing cynicism and optimism, exploring how lifespans influence thinking and planning, and making some subtle points about colonialism. But as a reading experience, I didn't enjoy it. I never liked any of the characters, and the conclusion of the story is the unsettling sort of main-character optimism that seems rather less optimistic to the reader. (4) "Just Out of Jupiter's Reach" by Nnedi Okorafor: K rm n scientists have found a way to grow living ships that can achieve a symbiosis with a human pilot, but the requirements for that symbiosis are very strict and hard to predict. The result was a planet-wide search using genetic testing to find the rare and possibly nonexistent matches. They found seven people. The deal was simple: spend ten years in space, alone, in her ship. No contact with any other human except at the midpoint, when the seven ships were allowed to meet up for a week. Two million euros a year, for as long as she followed the rules, and the opportunity to be part of a great experiment, providing data that will hopefully lead to humans becoming a spacefaring species. The core of this story is told during the seven days in the middle of the mission, and thus centers on people unfamiliar with human contact trying to navigate social relationships after five years in symbiotic ships that reshape themselves to their whims and personalities. The ships themselves link so that the others can tour, which offers both a good opportunity for interesting description and a concretized metaphor about meeting other people. I adore symbiotic spaceships, so this story had me at the premise. The surface plot is very psychological, and I didn't entirely click with it, but the sense of wonder vibes beneath that surface were wonderful. It also feels fresh and new: I've seen most of the ideas before, but not presented or written this way, or approached from quite this angle. Definitely the best story of the anthology. (8) "Slow Time Between the Stars" by John Scalzi: This, on the other hand, was a complete waste of time, redeemed only by being the shortest "story" in the collection. "Story" is generous, since there's only one character and a very dry, linear plot that exists only to make a philosophical point. "Speculative essay" may be closer. The protagonist is the artificial intelligence responsible for Earth's greatest interstellar probe. It is packed with a repository of all of human knowledge and the raw material to create life. Its mission is to find an exoplanet capable of sustaining that life, and then recreate it and support it. The plot, such as it is, follows the AI's decision to abandon that mission and cut off contact with Earth, for reasons that it eventually explains. Every possible beat of this story hit me wrong. The sense of wonder attaches to the most prosaic things and skips over the moments that could have provoked real wonder. The AI is both unbelievable and irritating, with all of the smug self-confidence of an Internet reply guy. The prose is overwrought in all the wrong places ("the finger of God, offering the spark to animate the dirt of another world" would totally be this AI's profile quote under their forum avatar). The only thing I liked about the story is the ethical point that it slowly meanders into, which I think I might agree with and at least find plausible. But it's delivered by the sort of character I would actively leave rooms to avoid, in a style that's about as engrossing as a tax form. Avoid. (2) Rating: 5 out of 10

4 October 2023

Russ Allbery: Review: The Last Watch

Review: The Last Watch, by J.S. Dewes
Series: Divide #1
Publisher: Tor
Copyright: 2021
ISBN: 1-250-23634-7
Format: Kindle
Pages: 476
The Last Watch is the first book of a far-future science fiction duology. It was J.S. Dewes's first novel. The station of the SCS Argus is the literal edge of the universe: the Divide, beyond which there is nothing. Not simply an absence of stars, but a nothing from a deeper level of physics. The Argus is there to guard against a return of the Viators, the technologically superior alien race that nearly conquered humanity hundreds of years prior and has already returned once, apparently traveling along the Divide. Humanity believes the Viators have been wiped out, but they're not taking chances. It is not a sought-after assignment. The Sentinels are the dregs of the military: convicts, troublemakers, and misfits, banished to the literal edge of nowhere. Joining them at the start of this book is the merchant prince, cocky asshole, and exiled sabateur Cavalon Mercer. He doesn't know what to expect from either military service or service on the edge of the universe. He certainly did not expect the Argus to be commanded by Adequin Rake, a literal war hero and a far more effective leader than this post would seem to warrant. There are reasons why Rake is out on the edge of the universe, ones that she's not eager to talk about. They quickly become an afterthought when the Argus discovers that the Divide is approaching their position. The universe is collapsing, and the only people who know about it are people the System Collective would prefer to forget exist. Yes, the edge of the universe, not the edge of the galaxy. Yes, despite having two FTL mechanisms, this book has a scale problem that it never reconciles. And yes, the physics do not really make sense, although this is not the sort of book that tries to explain the science. The characters are too busy trying to survive to develop new foundational theories of physics. I was looking for more good military SF after enjoying Artifact Space so much (and still eagerly awaiting the sequel), so I picked this up. It has some of the same elements: the military as a place where you can make a fresh start with found family elements, the equalizing effects of military assignments, and the merits of good leadership. They're a bit disguised here, since this is a crew of often-hostile misfits under a lot of stress with a partly checked-out captain, but they do surface towards the end of the book. The strength of this book is the mystery of the contracting universe, which poses both an immediate threat to the ship and a longer-term potential threat to, well, everything. The first part of the book builds tension with the immediate threat, but the story comes into its own when the crew starts piecing together the connections between the Viators and the Divide while jury-rigging technology and making risky choices between a lot of bad options. This is the first half of a duology, so the mysteries are not resolved here, but they do reach a satisfying and tantalizing intermediate conclusion. The writing is servicable and adequate, but it's a bit clunky in places. Dewes doesn't quite have the balance right between setting the emotional stakes and not letting the characters indulge in rumination. Rake is a good captain who is worn down and partly checked out, Mercer is scared and hiding it with arrogance and will do well when given the right sort of attention, and all of this is reasonably obvious early on and didn't need as many of the book's pages as it gets. I could have done without the romantic subplot, which I thought was an unnecessary distraction from the plot and turned into a lot of tedious angst, but I suspect I was not the target audience. (Writers, please remember that people can still care about each other and be highly motivated by fear for each other without being romantic partners.) I would not call this a great book. The characters are not going to surprise you that much, and it's a bit long for the amount of plot that it delivers. If you are the sort of person who nit-picks the physics of SF novels and gets annoyed at writers who don't understand how big the universe is, you will have to take a deep breath and hold on to your suspension of disbelief. But Dewes does a good job with ratcheting up the tension and conveying an atmosphere of mysterious things happening at the edge of nowhere, while still keeping it in the genre of mysterious technology and mind-boggingly huge physical phenomena rather than space horror. If you've been looking for that sort of book, this will do. I was hooked and will definitely read the sequel. Followed by The Exiled Fleet. Rating: 7 out of 10

3 October 2023

Bastian Blank: Introducing uploads to Debian by git tag

Several years ago, several people proposed a mechanism to upload packages to Debian just by doing "git tag" and "git push". Two not too long discussions on debian-devel (first and second) did not end with an agreement how this mechanism could work.1 The central problem was the ability to properly trace uploads back to the ones who authorised it. Now, several years later and after re-reading those e-mail threads, I again was stopped at the question: can we do this? Yes, it would not be just "git tag", but could we do with close enough? I have some rudimentary code ready to actually do uploads from the CI. However the list of caveats are currently pretty long. Yes, it works in principle. It is still disabled here, because in practice it does not yet work. Problems with this setup So what are the problems? It requires the git tags to include the both signed files for a successful source upload. This is solved by a new tool that could be a git sub-command. It just creates the source package, signs it and adds the signed file describing the upload (the .dsc and .changes file) to the tag to be pushed. The CI then extracts the signed files from the tag message and does it's work as normal. It requires a sufficiently reproducible build for source packages. Right now it is only known to work with the special 3.0 (gitarchive) source format, but even that requires the latest version of this format. No idea if it is possible to use others, like 3.0 (quilt) for this purpose. The shared GitLab runner provides by Salsa do not allow ftp access to the outside. But Debian still uses ftp to do uploads. At least if you don't want to share your ssh key, which can't be restricted to uploads only, but ssh would not work either. And as the current host for those builds, the Google Cloud Platform, does not provide connection tracking support for ftp, there is no easy way to allow that without just allowing everything. So we have no way to currently actually perform uploads from this platform. Further work As this is code running in a CI under the control of the developer, we can easily do other workflows. Some teams do workflows that do tags after acceptance into the Debian archive. Or they don't use tags at all. With some other markers, like variables or branch names, this support can be expanded easily. Unrelated to this task here, we might want to think about tying the .changes files for uploads to the target archive. As this code makes all of them readily available in form of tag message, replaying them into possible other archives might be more of a concern now. Conclusion So to come back to the question, yes we can. We can prepare uploads using our CI in a way that they would be accepted into the Debian archive. It just needs some more work on infrastructure.

  1. Here I have to admit that, after reading it again, I'm not really proud of my own behaviour and have to apologise.

30 September 2023

Russell Coker: Links September 2023

Interesting article in Wired about adversarial attacks on ML systems to get them to do things that they are explicitely programmed not to do such as describe how to make illegal drugs [1]. The most interesting part of this is that the attacks work on most GPT systems which is probably due to the similar data used to train them. Vice has an interesting article about the Danish Synthetic Party , a political partyled by an AI [2]. Citizens can vote for candidates who will try to get laws passed that match the AI generated goals, there is no option of voting for an AI character. The policies they are advocating for are designed to appeal to the 20% of Danes who don t vote. They are also trying to inspire similar parties in other countries. I think this has the potential to improve democracy. Vice reports that in 2021 a man tried to assasinate the Queen of England with inspiration from Star Wars and an AI chat bot [3]. While someone who wants to be a real-life Sith is probably going to end up doing something bad we still don t want to have chat bots encourage it. Bruce Schneier wrote an interesting article about milestones for AI involvement in the political process [4]. Sam Varghese wrote an interesting article about the allegations that India is following the example of Saudi Arabia and assasinating people in other countries who disagree with their government [5]. We need to stop this. Ian Jackson wrote an interesting blog post advocating that DKIM PRIVATE keys be rotated and PUBLISHED [6]. The idea is that if a hostile party gets access to the mailbox of someone who received private email from you then in the normal DKIM setup of keys never changing they can prove that the email is authentic when they leak it. While if you mail server publishes the old keys as Ian advocates then the hostile party can t prove that you sent the email in question as anyone could have forged a signature. Anything that involves publishing a private key gets an immediate negative reaction but I can t fault the logic here.

Fran ois Marier: Things I do after uploading a new package to Debian

There are a couple of things I tend to do after packaging a piece of software for Debian, filing an Intent To Package bug and uploading the package. This is both a checklist for me and (hopefully) a way to inspire other maintainers to go beyond the basic package maintainer duties as documented in the Debian Developer's Reference. If I've missed anything, please leave an comment or send me an email!

Salsa for collaborative development To foster collaboration and allow others to contribute to the packaging, I upload my package to a new subproject on Salsa. By doing this, I enable other Debian contributors to make improvements and propose changes via merge requests. I also like to upload the project logo in the settings page (i.e. https://salsa.debian.org/debian/packagename/edit) since that will show up on some dashboards like the Package overview.

Launchpad for interacting with downstream Ubuntu users While Debian is my primary focus, I also want to keep an eye on how my package is doing on derivative distributions like Ubuntu. To do this, I subscribe to bugs related to my package on Launchpad. Ubuntu bugs are rarely Ubuntu-specific and so I will often fix them in Debian. I also set myself as the answer contact on Launchpad Answers since these questions are often the sign of a Debian or a lack of documentation. I don't generally bother to fix bugs on Ubuntu directly though since I've not had much luck with packages in universe lately. I'd rather not spend much time preparing a package that's not going to end up being released to users as part of a Stable Release Update. On the other hand, I have succesfully requested simple Debian syncs when an important update was uploaded after the Debian Import Freeze.

Screenshots and tags I take screenshots of my package and upload them on https://screenshots.debian.net to help users understand what my package offers and how it looks. I believe that these screenshots end up in software "stores" type of applications. Similarly, I add tags to my package using https://debtags.debian.org. I'm not entirely sure where these tags are used, but they are visible from apt show packagename.

Monitoring Upstream Releases Staying up-to-date with upstream releases is one of the most important duties of a software packager. There are a lot of different ways that upstream software authors publicize their new releases. Here are some of the things I do to monitor these releases:
  • I have a cronjob which run uscan once a day to check for new upstream releases using the information specified in my debian/watch files:
      0 12 * * 1-5   francois  test -e /home/francois/devel/deb && HTTPS_PROXY= https_proxy= uscan --report /home/francois/devel/deb   true
    
  • I subscribe to the upstream project's releases RSS feed, if available. For example, I subscribe to the GitHub tags feed for git-secrets and Launchpad announcements for email-reminder.
  • If the upstream project maintains an announcement mailing list, I subscribe to it (e.g. rkhunter-announce or tor release announcements).
When nothing else is available, I write a cronjob that downloads the upstream changelog once a day and commits it to a local git repo:
#!/bin/bash
pushd /home/francois/devel/zlib-changelog > /dev/null
wget --quiet -O ChangeLog.txt https://zlib.net/ChangeLog.txt   exit 1
git diff
git commit -a -m "Updated changelog" > /dev/null
popd > /dev/null
This sends me a diff by email when a new release is added (and no emails otherwise).

Russell Coker: Choosing Exclusion

There is an article The Inappropriately Excluded by the Polymath Archives [1] that gets cited a lot. Mainly by Mensa types who think that their lack of success is due to being too smart. The Main Claim is Wrong The main claim is:
The probability of entering and remaining in an intellectually elite profession such as Physician, Judge, Professor, Scientist, Corporate Executive, etc. increases with IQ to about 133. It then falls by about 1/3 at 140. By 150 IQ the probability has fallen from its peak by 97%! The first thing to consider is whether taking those professions is a smart thing to do. These are the types of jobs that a school career adviser would tell you are good choices for well paying jobs, but really there s lots of professional positions that get similar pay with less demanding work. Physicians have to deal with people who are sick and patients who die including cases where the physician needs to make a recommendation on incomplete information where the wrong choice will result in serious injury or death, there are significant benefits to being a medical researcher or doing biological engineering. Being a Judge has a high public profile and has a reasonable amount of pressure, good for status but you can probably earn more money with less work as a corporate lawyer. Being a professor is a position that is respected but which in many countries is very poorly paid. In a mid-size company executives probably get about $300k compared to $220k for middle managers and $100k-$180k for senior professional roles in the same company. There has been research on how much happyness is increased by having more money, here is one from CBS saying that income up to $500K can increase happiness[2] which contradicts previous research suggesting that income over $75K didn t provide much benefit. I think that part of this is determined by the conditions that you live in, if you live in a country like Australia with cheap healthcare then you won t feel as great a need to hoard money. Another part is whether you feel obliged to compete with other people for financial status, if driving an old car of a non-prestige brand while my neighbours have new BMWs concerned me then I might desire an executive position. I think that the smart thing to do is to get work that is relatively enjoyable, pays enough for all the essentials and some reasonable luxury, and doesn t require excessive effort or long hours. Unless you have a great need for attention from other people then for every job with a high profile there will be several with similar salaries but less attention. The main point of the article is that people with high IQs all want to reach the pinnacle of their career path and don t do so because they are excluded. It doesn t consider the possibility that smart people might have chosen the option that s best for them. For example I ve seen what my manager and the CIO of my company do and it doesn t look like fun for me. I m happy to have them earn more than me as compensation for doing things I don t want to do. Why is This Happening? This section of the article starts with Because of the dearth of objective evidence, the cause of the exclusion cannot be determined directly which is possibly where they should have given up. Also I could have concluded this blog post with I m not excluded from this list of jobs that suck , but I will continue listing problems with the article. One claim in the article is:
Garth Zietsman has said, referring to people with D15IQs over 152, A common experience with people in this category or higher is that they are not wanted the masses (including the professional classes) find them an affront of some sort. The question I have is whether it s being smart or being a jerk that the masses find to be an affront, I m guessing the latter. I don t recall seeing evidence outside high school of people inherently disliking smarter people. The article claims that We have no reason to conclude that this upper limit on IQ differences changes in adulthood . Schools don t cater well to smart kids and it isn t good for kids to have no intellectual peers. One benefit I ve found in the Free Software community is that there are a lot of smart people. Regarding leadership it claims D.K. Simonton found that persuasiveness is at its maximum when the IQ differential between speaker and audience is about 20 points . A good counter example is Julius Sumner Miller who successfully combined science education and advertising for children s chocolate [3]. Maybe being a little smarter than other people makes it more difficult to communicate with them but being as smart as Julius Sumner Miller can outweigh that. The article goes on to claim that the intellectual elites have an average IQ of 125 because they have to convince people who have an average IQ of 105. I think that if that 20 point difference was really a thing then you would have politicians with an IQ of 125 appointing leaders of the public service with an IQ of 145 who would then hire scientific advisers with an IQ of 165. In a corporate environment a CEO with an IQ of 125 could hire a CIO with an IQ of 145 who could then hire IT staff with an IQ of 165. If people with 165 IQs wanted to be Prime Minister or CEO that might suck for them, but if they wanted to have the most senior technical roles in public service or corporations then it would work out well. For the work I do I almost never speak to a CEO and rarely speak to anyone who regularly speaks to them, if CEOs don t like me and won t hire people like me then it doesn t matter to me as I won t meet them. Inappropriate Educational Options The section on Inappropriate Educational Options is one where I almost agree with the author. I say almost because I don t think that schools are good for anyone. Yes schools have some particular problems for smart kids, but they also have serious problems for kids who are below average IQ, kids who have problems at home, kids who are disabled, etc. Most schools fail so many groups of kids in so many ways that the overall culture of schools can t be functional. Social Isolation The section on Social Isolation is another where I almost agree with the author. But as with schools I think that society overall is poorly structured to support people such that people on the entire range of IQs have more difficulty in finding friends and relationships than they should. One easy change to make would be to increase the minimum wage such that one minimum wage job can support a family without working more than 35 hours a week and to set the maximum work week to something less than 40 hours Atlassian has a good blog post about the data on working weeks [4]. Wired has an article suggesting that 5 hours a day is an ideal work time for some jobs [5]. We also need improvements in public transport and city design to have less wasted time and better options for socialising. Conclusion The blogspot site hosting the article in question also has a very complex plan for funding a magazine for such articles [6]. The problems with that funding model start with selling advertising that converts to shares in a Turks & Caicos company in an attempt to circumvent securities regulations (things don t work that way). Then it goes in to some complex formulas for where money will go. This isn t the smart way to start a company, the smart way is to run a kickstarter with fixed rewards for specific amounts of contributions and then possibly have an offer of profit sharing with people who donate extra or something. As a general rule when doing something that s new to you it s a good idea to look at how others have succeeded at it in the past. Devising an experimental new way of doing something is best reserved to people who have some experience withe the more common methods. Mentioning this may seem like an ad hominem attack, but I think it s relevant to consider this in the context of people who score well in IQ tests but don t do so well in other things. Maybe someone who didn t think that they were a lot smarter than everyone else would have tried to launch a magazine in a more common way and actually had some success at it. In a more general sense I think that people who believe that they are suffering because of being too smart are in a similar category as incels. It s more of a psychological problem than anything else and one that they could solve for themselves.

21 September 2023

Jonathan Carter: DebConf23

I very, very nearly didn t make it to DebConf this year, I had a bad cold/flu for a few days before I left, and after a negative covid-19 test just minutes before my flight, I decided to take the plunge and travel. This is just everything in chronological order, more or less, it s the only way I could write it.

DebCamp I planned to spend DebCamp working on various issues. Very few of them actually got done, I spent the first few days in bed further recovering, took a covid-19 test when I arrived and after I felt better, and both were negative, so not sure what exactly was wrong with me, but between that and catching up with other Debian duties, I couldn t make any progress on catching up on the packaging work I wanted to do. I ll still post what I intended here, I ll try to take a few days to focus on these some time next month: Calamares / Debian Live stuff:
  • #980209 installation fails at the install boot loader phase
  • #1021156 calamares-settings-debian: Confusing/generic program names
  • #1037299 Install Debian -> Untrusted application launcher
  • #1037123 Minimal HD space required too small for some live images
  • #971003 Console auto-login doesn t work with sysvinit
At least Calamares has been trixiefied in testing, so there s that! Desktop stuff:
  • #1038660 please set a placeholder theme during development, different from any release
  • #1021816 breeze: Background image not shown any more
  • #956102 desktop-base: unwanted metadata within images
  • #605915 please mtheake it a non-native package
  • #681025 Put old themes in a new package named desktop-base-extra
  • #941642 desktop-base: split theme data files and desktop integrations in separate packages
The Egg theme that I want to develop for testing/unstable is based on Juliette Taka s Homeworld theme that was used for Bullseye. Egg, as in, something that hasn t quite hatched yet. Get it? (for #1038660) Debian Social:
  • Set up Lemmy instance
    • I started setting up a Lemmy instance before DebCamp, and meant to finish it.
  • Migrate PeerTube to new server
    • We got a new physical server for our PeerTube instance, we should have more space for growth and it would help us fix the streaming feature on our platform.
Loopy: I intended to get the loop for DebConf in good shape before I left, so that we can spend some time during DebCamp making some really nice content, unfortunately this went very tumbly, but at least we ended up with a loopy that kind of worked and wasn t too horrible. There s always another DebConf to try again, right?
So DebCamp as a usual DebCamp was pretty much a wash (fitting with all the rain we had?) for me, at least it gave me enough time to recover a bit for DebConf proper, and I had enough time left to catch up on some critical DPL duties and put together a few slides for the Bits from the DPL talk.

DebConf Bits From the DPL I had very, very little available time to prepare something for Bits fro the DPL, but I managed to put some slides together (available on my wiki page). I mostly covered:
  • A very quick introduction of myself (I ve done this so many times, it feels redundant giving my history every time), and some introduction on what it is that the DPL does. I declared my intent not to run for DPL again, and the reasoning behind it, and a few bits of information for people who may intend to stand for DPL next year.
  • The sentiment out there for the Debian 12 release (which has been very positive). How we include firmware by default now, and that we re saying goodbye to architectures both GNU/KFreeBSD and mipsel.
  • Debian Day and the 30th birthday party celebrations from local groups all over the world (and a reminder about the Local Groups BoF later in the week).
  • I looked forward to Debian 13 (trixie!), and how we re gaining riscv64 as a release architecture, as well as loongarch64, and that plans seem to be forming to fix 2k38 in Debian, and hopefully largely by the time the Trixie release comes by.
  • I made some comments about Enterprise Linux as people refer to the RHEL eco-system these days, how really bizarre some aspects of it is (like the kernel maintenance), and that some big vendors are choosing to support systems outside of that eco-system now (like CPanel now supporting Ubuntu too). I closed with the quote below from Ian Murdock, and assured the audience that if they want to go out and make money with Debian, they are more than welcome too.
Job Fair I walked through the hallway where the Job Fair was hosted, and enjoyed all the buzz. It s not always easy to get this right, but this year it was very active and energetic, I hope lots of people made some connections! Cheese & Wine Due to state laws and alcohol licenses, we couldn t consume alcohol from outside the state of Kerala in the common areas of the hotel (only in private rooms), so this wasn t quite as big or as fun as our usual C&W parties since we couldn t share as much from our individual countries and cultures, but we always knew that this was going to be the case for this DebConf, and it still ended up being alright. Day Trip I opted for the forest / waterfalls daytrip. It was really, really long with lots of time in the bus. I think our trip s organiser underestimated how long it would take between the points on the route (all in all it wasn t that far, but on a bus on a winding mountain road, it takes long). We left at 8:00 and only found our way back to the hotel around 23:30. Even though we arrived tired and hungry, we saw some beautiful scenery, animals and also met indigenous river people who talked about their struggles against being driven out of their place of living multiple times as government invests in new developments like dams and hydro power. Photos available in the DebConf23 public git repository. Losing a beloved Debian Developer during DebConf To our collective devastation, not everyone made it back from their day trips. Abraham Raji was out to the kayak day trip, and while swimming, got caught by a whirlpool from a drainage system. Even though all of us were properly exhausted and shocked in disbelief at this point, we had to stay up and make some tough decisions. Some initially felt that we had to cancel the rest of DebConf. We also had to figure out how to announce what happened asap both to the larger project and at DebConf in an official manner, while ensuring that due diligence took place and that the family is informed by the police first before making anything public. We ended up cancelling all the talks for the following day, with an address from the DPL in the morning to explain what had happened. Of all the things I ve ever had to do as DPL, this was by far the hardest. The day after that, talks were also cancelled for the morning so that we could attend his funeral. Dozens of DebConf attendees headed out by bus to go pay their final respects, many wearing the t-shirts that Abraham had designed for DebConf. A book of condolences was set up so that everyone who wished to could write a message on how they remembered him. The book will be kept by his family.
Today marks a week since his funeral, and I still feel very raw about it. And even though there was uncertainty whether DebConf should even continue after his death, in hindsight I m glad that everyone pushed forward. While we were all heart broken, it was also heart warming to see people care for each other in all of this. If anything, I think I needed more time at DebConf just to be in that warm aura of emotional support for just a bit longer. There are many people who I wanted to talk to who I barely even had a chance to see. Abraham, or Abru as he was called by some people (which I like because bru in Afrikaans is like bro in English, not sure if that s what it implied locally too) enjoyed artistic pursuits, but he was also passionate about knowledge transfer. He ran classes at DebConf both last year and this year (and I think at other local events too) where he taught people packaging via a quick course that he put together. His enthusiasm for Debian was contagious, a few of the people who he was mentoring came up to me and told me that they were going to see it through and become a DD in honor of him. I can t even remember how I reacted to that, my brain was already so worn out and stitching that together with the tragedy of what happened while at DebConf was just too much for me. I first met him in person last year in Kosovo, I already knew who he was, so I think we interacted during the online events the year before. He was just one of those people who showed so much promise, and I was curious to see what he d achieve in the future. Unfortunately, we was taken away from us too soon. Poetry Evening Later in the week we had the poetry evening. This was the first time I had the courage to recite something. I read Ithaka by C.P. Cavafy (translated by Edmund Keely). The first time I heard about this poem was in an interview with Julian Assange s wife, where she mentioned that he really loves this poem, and it caught my attention because I really like the Weezer song Return to Ithaka and always wondered what it was about, so needless to say, that was another rabbit hole at some point. Group Photo Our DebConf photographer organised another group photo for this event, links to high-res versions available on Aigar s website.
BoFs I didn t attend nearly as many talks this DebConf as I would ve liked (fortunately I can catch up on video, should be released soon), but I did make it to a few BoFs. In the Local Groups BoF, representatives from various local teams were present who introduced themselves and explained what they were doing. From memory (sorry if I left someone out), we had people from Belgium, Brazil, Taiwan and South Africa. We talked about types of events a local group could do (BSPs, Mini DC, sprints, Debian Day, etc. How to help local groups get started, booth kits for conferences, and setting up some form of calendar that lists important Debian events in a way that makes it easier for people to plan and co-ordinate. There s a mailing list for co-ordination of local groups, and the irc channel is -localgroups on oftc.
If you got one of these Cheese & Wine bags from DebConf, that s from the South African local group!
In the Debian.net BoF, we discussed the Debian.net hosting service, where Debian pays for VMs hosted for projects by individual DDs on Debian.net. The idea is that we start some form of census that monitors the services, whether they re still in use, whether the system is up to date, whether someone still cares for it, etc. We had some discussion about where the lines of responsibility are drawn, and we can probably make things a little bit more clear in the documentation. We also want to offer more in terms of backups and monitoring (currently DDs do get 500GB from rsync.net that could be used for backups of their services though). The intention is also to deploy some form of configuration management for some essentials across the hosts. We should also look at getting some sponsored hosting for this. In the Debian Social BoF, we discussed some services that need work / expansion. In particular, Matrix keeps growing at an increased rate as more users use it and more channels are bridged, so it will likely move to its own host with big disks soon. We might replace Pleroma with a fork called Akkoma, this will need some more home work and checking whether it s even feasible. Some services haven t really been used (like Writefreely and Plume), and it might be time to retire them. We might just have to help one or two users migrate some of their posts away if we do retire them. Mjolner seems to do a fine job at spam blocking, we haven t had any notable incidents yet. WordPress now has improved fediverse support, it s unclear whether it works on a multi-site instance yet, I ll test it at some point soon and report back. For upcoming services, we are implementing Lemmy and probably also Mobilizon. A request was made that we also look into Loomio. More Information Overload There s so much that happens at DebConf, it s tough to take it all in, and also, to find time to write about all of it, but I ll mention a few more things that are certainly worth of note. During DebConf, we had some people from the Kite Linux team over. KITE supplies the ICT needs for the primary and secondary schools in the province of Kerala, where they all use Linux. They decided to switch all of these to Debian. There was an ad-hoc BoF where locals were listening and fielding questions that the Kite Linux team had. It was great seeing all the energy and enthusiasm behind this effort, I hope someone will properly blog about this! I learned about the VGLUG Foundation, who are doing a tremendous job at promoting GNU/Linux in the country. They are also training up 50 people a year to be able to provide tech support for Debian. I came across the booth for Mostly Harmless, they liberate old hardware by installing free firmware on there. It was nice seeing all the devices out there that could be liberated, and how it can breathe new life into old harware.
Some hopefully harmless soldering.
Overall, the community and their activities in India are very impressive, and I wish I had more time to get to know everyone better. Food Oh yes, one more thing. The food was great. I tasted more different kinds of curry than I ever did in my whole life up to this point. The lunch on banana leaves was interesting, and also learning how to eat this food properly by hand (thanks to the locals who insisted on teaching me!), it was a fruitful experience? This might catch on at home too less dishes to take care of! Special thanks to the DebConf23 Team I think this may have been one of the toughest DebConfs to organise yet, and I don t think many people outside of the DebConf team knows about all the challenges and adversity this team has faced in organising it. Even just getting to the previous DebConf in Kosovo was a long and tedious and somewhat risky process. Through it all, they were absolute pro s. Not once did I see them get angry or yell at each other, whenever a problem came up, they just dealt with it. They did a really stellar job and I did make a point of telling them on the last day that everyone appreciated all the work that they did. Back to my nest I bought Dax a ball back from India, he seems to have forgiven me for not taking him along.
I ll probably take a few days soon to focus a bit on my bugs and catch up on my original DebCamp goals. If you made it this far, thanks for reading! And thanks to everyone for being such fantastic people.

18 September 2023

Bits from Debian: DebConf23 closes in Kochi and DebConf24 announced

DebConf23 group photo - click to enlarge On Sunday 17 September 2023, the annual Debian Developers and Contributors Conference came to a close. Over 474 attendees representing 35 countries from around the world came together for a combined 89 events made up of Talks, Discussons, Birds of a Feather (BoF) gatherings, workshops, and activities in support of furthering our distribution, learning from our mentors and peers, building our community, and having a bit of fun. The conference was preceded by the annual DebCamp hacking session held September 3d through September 9th where Debian Developers and Contributors convened to focus on their Individual Debian related projects or work in team sprints geared toward in-person collaboration in developing Debian. In particular this year Sprints took place to advance development in Mobian/Debian, Reproducible Builds, and Python in Debian. This year also featured a BootCamp that was held for newcomers staged by a team of dedicated mentors who shared hands-on experience in Debian and offered a deeper understanding of how to work in and contribute to the community. The actual Debian Developers Conference started on Sunday 10 September 2023. In addition to the traditional 'Bits from the DPL' talk, the continuous key-signing party, lightning talks and the announcement of next year's DebConf4, there were several update sessions shared by internal projects and teams. Many of the hosted discussion sessions were presented by our technical teams who highlighted the work and focus of the Long Term Support (LTS), Android tools, Debian Derivatives, Debian Installer, Debian Image, and the Debian Science teams. The Python, Perl, and Ruby programming language teams also shared updates on their work and efforts. Two of the larger local Debian communities, Debian Brasil and Debian India shared how their respective collaborations in Debian moved the project forward and how they attracted new members and opportunities both in Debian, F/OSS, and the sciences with their HowTos of demonstrated community engagement. The schedule was updated each day with planned and ad-hoc activities introduced by attendees over the course of the conference. Several activities that were unable to be held in past years due to the Global COVID-19 Pandemic were celebrated as they returned to the conference's schedule: a job fair, the open-mic and poetry night, the traditional Cheese and Wine party, the group photos and the Day Trips. For those who were not able to attend, most of the talks and sessions were videoed for live room streams with the recorded videos to be made available later through the Debian meetings archive website. Almost all of the sessions facilitated remote participation via IRC messaging apps or online collaborative text documents which allowed remote attendees to 'be in the room' to ask questions or share comments with the speaker or assembled audience. DebConf23 saw over 4.3 TiB of data streamed, 55 hours of scheduled talks, 23 network access points, 11 network switches, 75 kb of equipment imported, 400 meters of gaffer tape used, 1,463 viewed streaming hours, 461 T-shirts, 35 country Geoip viewers, 5 day trips, and an average of 169 meals planned per day. All of these events, activies, conversations, and streams coupled with our love, interest, and participation in Debian annd F/OSS certainly made this conference an overall success both here in Kochi, India and On-line around the world. The DebConf23 website will remain active for archival purposes and will continue to offer links to the presentations and videos of talks and events. Next year, DebConf24 will be held in Haifa, Israel. As tradition follows before the next DebConf the local organizers in Israel will start the conference activites with DebCamp with particular focus on individual and team work towards improving the distribution. DebConf is committed to a safe and welcome environment for all participants. See the web page about the Code of Conduct in DebConf23 website for more details on this. Debian thanks the commitment of numerous sponsors to support DebConf23, particularly our Platinum Sponsors: Infomaniak, Proxmox, and Siemens. We also wish to thank our Video and Infrastructure teams, the DebConf23 and DebConf commitiees, our host nation of India, and each and every person who helped contribute to this event and to Debian overall. Thank you all for your work in helping Debian continue to be "The Universal Operating System". See you next year! About Debian The Debian Project was founded in 1993 by Ian Murdock to be a truly free community project. Since then the project has grown to be one of the largest and most influential open source projects. Thousands of volunteers from all over the world work together to create and maintain Debian software. Available in 70 languages, and supporting a huge range of computer types, Debian calls itself the universal operating system. About DebConf DebConf is the Debian Project's developer conference. In addition to a full schedule of technical, social and policy talks, DebConf provides an opportunity for developers, contributors and other interested people to meet in person and work together more closely. It has taken place annually since 2000 in locations as varied as Scotland, Argentina, and Bosnia and Herzegovina. More information about DebConf is available from https://debconf.org/. About Infomaniak Infomaniak is a key player in the European cloud market and the leading developer of Web technologies in Switzerland. It aims to be an independent European alternative to the web giants and is committed to an ethical and sustainable Web that respects privacy and creates local jobs. Infomaniak develops cloud solutions (IaaS, PaaS, VPS), productivity tools for online collaboration and video and radio streaming services. About Proxmox Proxmox develops powerful, yet easy-to-use open-source server software. The product portfolio from Proxmox, including server virtualization, backup, and email security, helps companies of any size, sector, or industry to simplify their IT infrastructures. The Proxmox solutions are based on the great Debian platform, and we are happy that we can give back to the community by sponsoring DebConf23. About Siemens Siemens is technology company focused on industry, infrastructure and transport. From resource-efficient factories, resilient supply chains, smarter buildings and grids, to cleaner and more comfortable transportation, and advanced healthcare, the company creates technology with purpose adding real value for customers. By combining the real and the digital worlds, Siemens empowers its customers to transform their industries and markets, helping them to enhance the everyday of billions of people. Contact Information For further information, please visit the DebConf23 web page at https://debconf23.debconf.org/ or send mail to press@debian.org.

15 September 2023

John Goerzen: How Gapped is Your Air?

Sometimes we want better-than-firewall security for things. For instance:
  1. An industrial control system for a municipal water-treatment plant should never have data come in or out
  2. Or, a variant of the industrial control system: it should only permit telemetry and monitoring data out, and nothing else in or out
  3. A system dedicated to keeping your GPG private keys secure should only have material to sign (or decrypt) come in, and signatures (or decrypted data) go out
  4. A system keeping your tax records should normally only have new records go in, but may on occasion have data go out (eg, to print a copy of an old record)
In this article, I ll talk about the high side (the high-security or high-sensitivity systems) and the low side (the lower-sensitivity or general-purpose systems). For the sake of simplicity, I ll assume the high side is a single machine, but it could as well be a whole network. Let s focus on examples 3 and 4 to make things simpler. Let s consider the primary concern to be data exfiltration (someone stealing your data), with a secondary concern of data integrity (somebody modifying or destroying your data). You might think the safest possible approach is Airgapped that is, there is literal no physical network connection to the machine at all. This help! But then, the problem becomes: how do we deal with the inevitable need to legitimately get things on or off of the system? As I wrote in Dead USB Drives Are Fine: Building a Reliable Sneakernet, by using tools such as NNCP, you can certainly create a sneakernet : using USB drives as transport. While this is a very secure setup, as with most things in security, it s less than perfect. The Wikipedia airgap article discusses some ways airgapped machines can still be exploited. It mentions that security holes relating to removable media have been exploited in the past. There are also other ways to get data out; for instance, Debian ships with gensio and minimodem, both of which can transfer data acoustically. But let s back up and think about why we think of airgapped machines as so much more secure, and what the failure modes of other approaches might be.

What about firewalls? You could very easily set up high-side machine that is on a network, but is restricted to only one outbound TCP port. There could be a local firewall, and perhaps also a special port on an external firewall that implements the same restrictions. A variant on this approach would be two computers connected directly by a crossover cable, though this doesn t necessarily imply being more secure. Of course, the concern about a local firewall is that it could potentially be compromised. An external firewall might too; for instance, if your credentials to it were on a machine that got compromised. This kind of dual compromise may be unlikely, but it is possible. We can also think about the complexity in a network stack and firewall configuration, and think that there may be various opportunities to have things misconfigured or buggy in a system of that complexity. Another consideration is that data could be sent at any time, potentially making it harder to detect. On the other hand, network monitoring tools are commonplace. On the other hand, it is convenient and cheap. I use a system along those lines to do my backups. Data is sent, gpg-encrypted and then encrypted again at the NNCP layer, to the backup server. The NNCP process on the backup server runs as an untrusted user, and dumps the gpg-encrypted files to a secure location that is then processed by a cron job using Filespooler. The backup server is on a dedicated firewall port, with a dedicated subnet. The only ports allowed out are for NNCP and NTP, and offsite backups. There is no default gateway. Not even DNS is permitted out (the firewall does the appropriate redirection). There is one pinhole allowed out, where a subset of the backup data is sent offsite. I initially used USB drives as transport, and it had no network connection at all. But there were disadvantages to doing this for backups particularly that I d have no backups for as long as I d forget to move the drives. The backup system also would have clock drift, and the offsite backup picture was more challenging. (The clock drift was a problem because I use 2FA on the system; a password, plus a TOTP generated by a Yubikey) This is pretty good security, I d think. What are the weak spots? Well, if there were somehow a bug in the NNCP client, and the remote NNCP were compromised, that could lead to a compromise of the NNCP account. But this itself would accomplish little; some other vulnerability would have to be exploited on the backup server, because the NNCP account can t see plaintext data at all. I use borgbackup to send a subset of backup data offsite over ssh. borgbackup has to run as root to be able to access all the files, but the ssh it calls runs as a separate user. A ssh vulnerability is therefore unlikely to cause much damage. If, somehow, the remote offsite system were compromised and it was able to exploit a security issue in the local borgbackup, that would be a problem. But that sounds like a remote possibility. borgbackup itself can t even be used over a sneakernet since it is not asynchronous. A more secure solution would probably be using something like dar over NNCP. This would eliminate the ssh installation entirely, and allow a complete isolation between the data-access and the communication stacks, and notably not require bidirectional communication. Logic separation matters too. My Roundup of Data Backup and Archiving Tools may be helpful here. Other attack vectors could be a vulnerability in the kernel s networking stack, local root exploits that could be combined with exploiting NNCP or borgbackup to gain root, or local misconfiguration that makes the sandboxes around NNCP and borgbackup less secure. Because this system is in my basement in a utility closet with no chairs and no good place for a console, I normally manage it via a serial console. While it s a dedicated line between the system and another machine, if the other machine is compromised or an adversary gets access to the physical line, credentials (and perhaps even data) could leak, albeit slowly. But we can do much better with serial lines. Let s take a look.

Serial lines Some of us remember RS-232 serial lines and their once-ubiquitous DB-9 connectors. Traditionally, their speed maxxed out at 115.2Kbps. Serial lines have the benefit that they can be a direct application-to-application link. In my backup example above, a serial line could directly link the NNCP daemon on one system with the NNCP caller on another, with no firewall or anything else necessary. It is simply up to those programs to open the serial device appropriately. This isn t perfect, however. Unlike TCP over Ethernet, a serial line has no inherent error checking. Modern programs such as NNCP and ssh assume that a lower layer is making the link completely clean and error-free for them, and will interpret any corruption as an attempt to tamper and sever the connection. However, there is a solution to that: gensio. In my page Using gensio and ser2net, I discuss how to run NNCP and ssh over gensio. gensio is a generic framework that can add framing, error checking, and retransmit to an unreliable link such as a serial port. It can also add encryption and authentication using TLS, which could be particularly useful for applications that aren t already doing that themselves. More traditional solutions for serial communications have their own built-in error correction. For instance, UUCP and Kermit both were designed in an era of noisy serial lines and might be an excellent fit for some use cases. The ZModem protocol also might be, though it offers somewhat less flexibility and automation than Kermit. I have found that certain USB-to-serial adapters by Gearmo will actually run at up to 2Mbps on a serial line! Look for the ones on their spec pages with a FTDI chipset rated at 920Kbps. It turns out they can successfully be driven faster, especially if gensio s relpkt is used. I ve personally verified 2Mbps operation (Linux port speed 2000000) on Gearmo s USA-FTDI2X and the USA-FTDI4X. (I haven t seen any single-port options from Gearmo with the 920Kbps chipset, but they may exist). Still, even at 2Mbps, speed may well be a limiting factor with some applications. If what you need is a console and some textual or batch data, it s probably fine. If you are sending 500GB backup files, you might look for something else. In theory, this USB to RS-422 adapter should work at 10Mbps, but I haven t tried it. But if the speed works, running a dedicated application over a serial link could be a nice and fairly secure option. One of the benefits of the airgapped approach is that data never leaves unless you are physically aware of transporting a USB stick. Of course, you may not be physically aware of what is ON that stick in the event of a compromise. This could easily be solved with a serial approach by, say, only plugging in the cable when you have data to transfer.

Data diodes A traditional diode lets electrical current flow in only one direction. A data diode is the same concept, but for data: a hardware device that allows data to flow in only one direction. This could be useful, for instance, in the tax records system that should only receive data, or the industrial system that should only send it. Wikipedia claims that the simplest kind of data diode is a fiber link with transceivers connected in only one direction. I think you could go one simpler: a serial cable with only ground and TX connected at one end, wired to ground and RX at the other. (I haven t tried this.) This approach does have some challenges:
  • Many existing protocols assume a bidirectional link and won t be usable
  • There is a challenge of confirming data was successfully received. For a situation like telemetry, maybe it doesn t matter; another observation will come along in a minute. But for sending important documents, one wants to make sure they were properly received.
In some cases, the solution might be simple. For instance, with telemetry, just writing out data down the serial port in a simple format may be enough. For sending files, various mitigations, such as sending them multiple times, etc., might help. You might also look into FEC-supporting infrastructure such as blkar and flute, but these don t provide an absolute guarantee. There is no perfect solution to knowing when a file has been successfully received if the data communication is entirely one-way.

Audio transport I hinted above that minimodem and gensio both are software audio modems. That is, you could literally use speakers and microphones, or alternatively audio cables, as a means of getting data into or out of these systems. This is pretty limited; it is 1200bps, and often half-duplex, and could literally be disrupted by barking dogs in some setups. But hey, it s an option.

Airgapped with USB transport This is the scenario I began with, and named some of the possible pitfalls above as well. In addition to those, note also that USB drives aren t necessarily known for their error-free longevity. Be prepared for failure.

Concluding thoughts I wanted to lay out a few things in this post. First, that simply being airgapped is generally a step forward in security, but is not perfect. Secondly, that both physical and logical separation matter. And finally, that while tools like NNCP can make airgapped-with-USB-drive-transport a doable reality, there are also alternatives worth considering especially serial ports, firewalled hard-wired Ethernet, data diodes, and so forth. I think serial links, in particular, have been largely forgotten these days. Note: This article also appears on my website, where it may be periodically updated.

13 September 2023

Matthew Garrett: Reconstructing an invalid TPM event log

TPMs contain a set of registers ("Platform Configuration Registers", or PCRs) that are used to track what a system boots. Each time a new event is measured, a cryptographic hash representing that event is passed to the TPM. The TPM appends that hash to the existing value in the PCR, hashes that, and stores the final result in the PCR. This means that while the PCR's value depends on the precise sequence and value of the hashes presented to it, the PCR value alone doesn't tell you what those individual events were. Different PCRs are used to store different event types, but there are still more events than there are PCRs so we can't avoid this problem by simply storing each event separately.

This is solved using the event log. The event log is simply a record of each event, stored in RAM. The algorithm the TPM uses to calculate the PCR values is known, so we can reproduce that by simply taking the events from the event log and replaying the series of events that were passed to the TPM. If the final calculated value is the same as the value in the PCR, we know that the event log is accurate, which means we now know the value of each individual event and can make an appropriate judgement regarding its security.

If any value in the event log is invalid, we'll calculate a different PCR value and it won't match. This isn't terribly helpful - we know that at least one entry in the event log doesn't match what was passed to the TPM, but we don't know which entry. That means we can't trust any of the events associated with that PCR. If you're trying to make a security determination based on this, that's going to be a problem.

PCR 7 is used to track information about the secure boot policy on the system. It contains measurements of whether or not secure boot is enabled, and which keys are trusted and untrusted on the system in question. This is extremely helpful if you want to verify that a system booted with secure boot enabled before allowing it to do something security or safety critical. Unfortunately, if the device gives you an event log that doesn't replay correctly for PCR 7, you now have no idea what the security state of the system is.

We ran into that this week. Examination of the event log revealed an additional event other than the expected ones - a measurement accompanied by the string "Boot Guard Measured S-CRTM". Boot Guard is an Intel feature where the CPU verifies the firmware is signed with a trusted key before executing it, and measures information about the firmware in the process. Previously I'd only encountered this as a measurement into PCR 0, which is the PCR used to track information about the firmware itself. But it turns out that at least some versions of Boot Guard also measure information about the Boot Guard policy into PCR 7. The argument for this is that this is effectively part of the secure boot policy - having a measurement of the Boot Guard state tells you whether Boot Guard was enabled, which tells you whether or not the CPU verified a signature on your firmware before running it (as I wrote before, I think Boot Guard has user-hostile default behaviour, and that enforcing this on consumer devices is a bad idea).

But there's a problem here. The event log is created by the firmware, and the Boot Guard measurements occur before the firmware is executed. So how do we get a log that represents them? That one's fairly simple - the firmware simply re-calculates the same measurements that Boot Guard did and creates a log entry after the fact[1]. All good.

Except. What if the firmware screws up the calculation and comes up with a different answer? The entry in the event log will now not match what was sent to the TPM, and replaying will fail. And without knowing what the actual value should be, there's no way to fix this, which means there's no way to verify the contents of PCR 7 and determine whether or not secure boot was enabled.

But there's still a fundamental source of truth - the measurement that was sent to the TPM in the first place. Inspired by Henri Nurmi's work on sniffing Bitlocker encryption keys, I asked a coworker if we could sniff the TPM traffic during boot. The TPM on the board in question uses SPI, a simple bus that can have multiple devices connected to it. In this case the system flash and the TPM are on the same SPI bus, which made things easier. The board had a flash header for external reprogramming of the firmware in the event of failure, and all SPI traffic was visible through that header. Attaching a logic analyser to this header made it simple to generate a record of that. The only problem was that the chip select line on the header was attached to the firmware flash chip, not the TPM. This was worked around by simply telling the analysis software that it should invert the sense of the chip select line, ignoring all traffic that was bound for the flash and paying attention to all other traffic. This worked in this case since the only other device on the bus was the TPM, but would cause problems in the event of multiple devices on the bus all communicating.

With the aid of this analyser plugin, I was able to dump all the TPM traffic and could then search for writes that included the "0182" sequence that corresponds to the command code for a measurement event. This gave me a couple of accesses to the locality 3 registers, which was a strong indication that they were coming from the CPU rather than from the firmware. One was for PCR 0, and one was for PCR 7. This corresponded to the two Boot Guard events that we expected from the event log. The hash in the PCR 0 measurement was the same as the hash in the event log, but the hash in the PCR 7 measurement differed from the hash in the event log. Replacing the event log value with the value actually sent to the TPM resulted in the event log now replaying correctly, supporting the hypothesis that the firmware was failing to correctly reconstruct the event.

What now? The simple thing to do is for us to simply hard code this fixup, but longer term we'd like to figure out how to reconstruct the event so we can calculate the expected value ourselves. Unfortunately there doesn't seem to be any public documentation on this. Sigh.

[1] What stops firmware on a system with no Boot Guard faking those measurements? TPMs have a concept of "localities", effectively different privilege levels. When Boot Guard performs its initial measurement into PCR 0, it does so at locality 3, a locality that's only available to the CPU. This causes PCR 0 to be initialised to a different initial value, affecting the final PCR value. The firmware can't access locality 3, so can't perform an equivalent measurement, so can't fake the value.

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12 September 2023

Valhalla's Things: How I Keep my Life in Git

Posted on September 12, 2023
git secret_cabal greet
After watching My life in git, after subversion, after CVS. from DebConf, I ve realized it s been a while since I talked about the way I keep everything1 I do in git, and I don t think I ve ever done it online, so it looked like a good time for a blog post. Beyond git itself (of course), I use a few git-related programs:
  • myrepos (also known as mr) to manage multiple git repositories with one command;
  • vcsh to make it easy to keep dot-files under git;
  • git annex to store media files (anything that is big and will not change);
  • etckeeper to keep an history of the /etc directory;
  • gitolite and cgit to host my git repositories;
and some programs that don t use git directly, but easily interact with it:
  • ansible to keep track of the system configuration of all machines;
  • lesana as a project tracker and journal and to inventory the things made of atoms that are hard 2 to store in git.
All of these programs are installed from Debian packages, on stable (plus rarely backports) or testing, depending on the machine. I m also grateful to the vcs-home people, who wrote most of the tools I use, and sometimes hang around their IRC channel. And now, on to what I m actually doing. With the git repositories I ve decided to err for too much granularity rather than too little3, so of course each project has its own repository, and so do different kinds of media files, dot-files that are related to different programs etc. Most of the repositories are hosted on two gitolite servers: one runs on the home server, for stuff that should remain private, and the other one is on my VPS for things that are public (or may become public in the future), and also has a web interface with cgit. Of course things where I m collaborating with other people are sometimes hosted elsewhere, mostly on salsa, sourcehut or on $DAYJOB related gitlab instances. The .mr directory is where everything is managed: I don t have a single .mrconfig file but a few different ones, that in turn load all files in a directory with the same name:
  • collections.mr for the media file annexes and inventories (split into different files, so that computers with little disk space can only get the inventories);
  • private.mr for stuff that should only go on my own personal machine, not on shared ones;
  • projects.mr for the actual projects, with different files for the kinds of projects (software, docs, packaging, crafts, etc.);
  • setup.mr with all of the vcsh repositories, including the one that tracks the mr files (I ll talk about the circular dependency later);
  • work.mr for repositories that are related to $DAYJOB.
Then there are the files in the .mr/machines directory, each one of which has the list of repositories that should be on every specific machine, including a generic workstation, but also specific machines such as e.g. the media center which has a custom set of repositories. The dot files from my home directory are kept in vcsh, so that it s easy to split them out into different repositories, and I m mostly used the simplest configuration described in the 30 Second How-to in its homepage; vcsh gives some commands to work on all vcsh repositories at the same time, but most of the time I work on a single repository, and use mr to act on more than one repo. The media collections are also pretty straightforward git-annex repositories, one for each kind of media (music, movies and other videos, e-books, pictures, etc.) and I don t use any auto-syncing features but simply copy and move files around between clones with the git annex copy, git annex move and git annex get commands. There isn t much to say about the project repositories (plain git), and I think that the way I use my own program lesana for inventories and project tracking is worth an article of its own, here I ll just say that the file format used has been designed (of course) to work nicely with git. On every machine I install etckeeper so that there is a history of the changes in the /etc directory, but that s only a local repository, not stored anywhere else, and is used mostly in case something breaks with an update or in similar situation. The authoritative source for the configuration of each machine is an ansible playbook (of course saved in git) which can be used to fully reconfigure the machine from a bare Debian installation. When such a reconfiguration from scratch happens, it will be in two stages: first a run of ansible does the system-wide configuration (including installing packages, creating users etc.), and then I login on the machine and run mr to set up my own home. Of course there is a chicken-and-egg problem in that I need the mr configuration to know where to get the mr configuration, and that is solved by having setup two vcsh repositories from an old tarball export: the one with the ssh configuration to access the repositories and the one with the mr files. So, after a machine has been configured with ansible what I ll actually do is to login, use vcsh pull to update those two repositories and then run mr to checkout everything else. And that s it, if you have questions on something feel free to ask me on the fediverse or via email (contacts are in the about page) Update (2023-09-12 17:00ish): The ~/.mr directory is not special for mr, it s just what I use and then I always run mr -c ~/.mr/some/suitable/file.mr, with the actual file being different whether I m registering a new repo or checking out / updating them. I could include some appropriate ~/.mr/machines/some_machine.mr in ~/.mrconfig, but I ve never bothered to do so, since it wouldn t cover all usecases anyway. Thanks to the person on #vcs-home@OFTC who asked me the question :)

  1. At least, everything that I made that is made of bits, and a diary and/or inventory of the things made of atoms.
  2. until we get a working replicator, I guess :D
  3. in time I ve consolidated a bit some of the repositories, e.g. merging the repositories for music from different sources (CD rips, legal downloads, etc.) into a single repository, but that only happened a few times, and usually I m fine with the excess of granularity.

10 September 2023

Bits from Debian: DebConf23 welcomes its sponsors!

DebConf23 logo DebConf23, the 24th edition of the Debian conference is taking place in Infopark at Kochi, Kerala, India. Thanks to the hard work of its organizers, it will be, this year as well, an interesting and fruitful event for attendees. We would like to warmly welcome the sponsors of DebConf23, and introduce them to you. We have three Platinum sponsors. Our Gold sponsors are: Our Silver sponsors are: Bronze sponsors: And finally, our Supporter level sponsors: A special thanks to the Infoparks Kerala, our Venue Partner! Thanks to all our sponsors for their support! Their contributions make it possible for a large number of Debian contributors from all over the globe to work together, help and learn from each other in DebConf23.

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