September 30, 2022

hackergotchi for Jonathan Dowland

Jonathan Dowland

vim-css-color

Last year I wrote about a subset of the vim plugins I was using, specifically those created by master craftsman Tim Pope. Off and on since then I've reviewed the other plugins I use and tried a few others, so I thought I'd write about them.

automatic colour name colouring

automatic colour name colouring

vim-css-color is a simple plugin that recognised colour names specified in CSS-style: e.g. 'red', '#ff0000', '#rgb(255,0,0)' etc., and colours them accordingly. True to its name, once installed it's active when editing CSS files, but it's also supported for many other file types, and extending it further is not hard.

30 September, 2022 07:48PM

Reproducible Builds (diffoscope)

diffoscope 223 released

The diffoscope maintainers are pleased to announce the release of diffoscope version 223. This version includes the following changes:

[ Chris Lamb ]
* The cbfstools utility is now provided in Debian via the coreboot-utils
  Debian package, so we can enable that functionality within Debian.
  (Closes: #1020630)

[ Mattia Rizzolo ]
* Also include coreboot-utils in Build-Depends and Test-Depends so it is
  available for the tests.

[ Jelle van der Waa ]
* Add support for file 5.43.

You find out more by visiting the project homepage.

30 September, 2022 12:00AM

September 29, 2022

Antoine Beaupré

Detecting manual (and optimizing large) package installs in Puppet

Well this is a mouthful.

I recently worked on a neat hack called puppet-package-check. It is designed to warn about manually installed packages, to make sure "everything is in Puppet". But it turns out it can (probably?) dramatically decrease the bootstrap time of Puppet bootstrap when it needs to install a large number of packages.

Detecting manual packages

On a cleanly filed workstation, it looks like this:

root@emma:/home/anarcat/bin# ./puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
0 unmanaged packages found

A messy workstation will look like this:

root@curie:/home/anarcat/bin# ./puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
288 unmanaged packages found
apparmor-utils beignet-opencl-icd bridge-utils clustershell cups-pk-helper davfs2 dconf-cli dconf-editor dconf-gsettings-backend ddccontrol ddrescueview debmake debootstrap decopy dict-devil dict-freedict-eng-fra dict-freedict-eng-spa dict-freedict-fra-eng dict-freedict-spa-eng diffoscope dnsdiag dropbear-initramfs ebtables efibootmgr elpa-lua-mode entr eog evince figlet file file-roller fio flac flex font-manager fonts-cantarell fonts-inconsolata fonts-ipafont-gothic fonts-ipafont-mincho fonts-liberation fonts-monoid fonts-monoid-tight fonts-noto fonts-powerline fonts-symbola freeipmi freetype2-demos ftp fwupd-amd64-signed gallery-dl gcc-arm-linux-gnueabihf gcolor3 gcp gdisk gdm3 gdu gedit gedit-plugins gettext-base git-debrebase gnome-boxes gnote gnupg2 golang-any golang-docker-credential-helpers golang-golang-x-tools grub-efi-amd64-signed gsettings-desktop-schemas gsfonts gstreamer1.0-libav gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-ugly gstreamer1.0-pulseaudio gtypist gvfs-backends hackrf hashcat html2text httpie httping hugo humanfriendly iamerican-huge ibus ibus-gtk3 ibus-libpinyin ibus-pinyin im-config imediff img2pdf imv initramfs-tools input-utils installation-birthday internetarchive ipmitool iptables iptraf-ng jackd2 jupyter jupyter-nbextension-jupyter-js-widgets jupyter-qtconsole k3b kbtin kdialog keditbookmarks keepassxc kexec-tools keyboard-configuration kfind konsole krb5-locales kwin-x11 leiningen lightdm lintian linux-image-amd64 linux-perf lmodern lsb-base lvm2 lynx lz4json magic-wormhole mailscripts mailutils manuskript mat2 mate-notification-daemon mate-themes mime-support mktorrent mp3splt mpdris2 msitools mtp-tools mtree-netbsd mupdf nautilus nautilus-sendto ncal nd ndisc6 neomutt net-tools nethogs nghttp2-client nocache npm2deb ntfs-3g ntpdate nvme-cli nwipe obs-studio okular-extra-backends openstack-clients openstack-pkg-tools paprefs pass-extension-audit pcmanfm pdf-presenter-console pdf2svg percol pipenv playerctl plymouth plymouth-themes popularity-contest progress prometheus-node-exporter psensor pubpaste pulseaudio python3-ldap qjackctl qpdfview qrencode r-cran-ggplot2 r-cran-reshape2 rake restic rhash rpl rpm2cpio rs ruby ruby-dev ruby-feedparser ruby-magic ruby-mocha ruby-ronn rygel-playbin rygel-tracker s-tui sanoid saytime scrcpy scrcpy-server screenfetch scrot sdate sddm seahorse shim-signed sigil smartmontools smem smplayer sng sound-juicer sound-theme-freedesktop spectre-meltdown-checker sq ssh-audit sshuttle stress-ng strongswan strongswan-swanctl syncthing system-config-printer system-config-printer-common system-config-printer-udev systemd-bootchart systemd-container tardiff task-desktop task-english task-ssh-server tasksel tellico texinfo texlive-fonts-extra texlive-lang-cyrillic texlive-lang-french texlive-lang-german texlive-lang-italian texlive-xetex tftp-hpa thunar-archive-plugin tidy tikzit tint2 tintin++ tipa tpm2-tools traceroute tree trocla ucf udisks2 unifont unrar-free upower usbguard uuid-runtime vagrant-cachier vagrant-libvirt virt-manager vmtouch vorbis-tools w3m wamerican wamerican-huge wfrench whipper whohas wireshark xapian-tools xclip xdg-user-dirs-gtk xlax xmlto xsensors xserver-xorg xsltproc xxd xz-utils yubioath-desktop zathura zathura-pdf-poppler zenity zfs-dkms zfs-initramfs zfsutils-linux zip zlib1g zlib1g-dev
157 old: apparmor-utils clustershell davfs2 dconf-cli dconf-editor ddccontrol ddrescueview decopy dnsdiag ebtables efibootmgr elpa-lua-mode entr figlet file-roller fio flac flex font-manager freetype2-demos ftp gallery-dl gcc-arm-linux-gnueabihf gcolor3 gcp gdu gedit git-debrebase gnote golang-docker-credential-helpers golang-golang-x-tools gtypist hackrf hashcat html2text httpie httping hugo humanfriendly iamerican-huge ibus ibus-pinyin imediff input-utils internetarchive ipmitool iptraf-ng jackd2 jupyter-qtconsole k3b kbtin kdialog keditbookmarks keepassxc kexec-tools kfind konsole leiningen lightdm lynx lz4json magic-wormhole manuskript mat2 mate-notification-daemon mktorrent mp3splt msitools mtp-tools mtree-netbsd nautilus nautilus-sendto nd ndisc6 neomutt net-tools nethogs nghttp2-client nocache ntpdate nwipe obs-studio openstack-pkg-tools paprefs pass-extension-audit pcmanfm pdf-presenter-console pdf2svg percol pipenv playerctl qjackctl qpdfview qrencode r-cran-ggplot2 r-cran-reshape2 rake restic rhash rpl rpm2cpio rs ruby-feedparser ruby-magic ruby-mocha ruby-ronn s-tui saytime scrcpy screenfetch scrot sdate seahorse shim-signed sigil smem smplayer sng sound-juicer spectre-meltdown-checker sq ssh-audit sshuttle stress-ng system-config-printer system-config-printer-common tardiff tasksel tellico texlive-lang-cyrillic texlive-lang-french tftp-hpa tikzit tint2 tintin++ tpm2-tools traceroute tree unrar-free vagrant-cachier vagrant-libvirt vmtouch vorbis-tools w3m wamerican wamerican-huge wfrench whipper whohas xdg-user-dirs-gtk xlax xmlto xsensors xxd yubioath-desktop zenity zip
131 new: beignet-opencl-icd bridge-utils cups-pk-helper dconf-gsettings-backend debmake debootstrap dict-devil dict-freedict-eng-fra dict-freedict-eng-spa dict-freedict-fra-eng dict-freedict-spa-eng diffoscope dropbear-initramfs eog evince file fonts-cantarell fonts-inconsolata fonts-ipafont-gothic fonts-ipafont-mincho fonts-liberation fonts-monoid fonts-monoid-tight fonts-noto fonts-powerline fonts-symbola freeipmi fwupd-amd64-signed gdisk gdm3 gedit-plugins gettext-base gnome-boxes gnupg2 golang-any grub-efi-amd64-signed gsettings-desktop-schemas gsfonts gstreamer1.0-libav gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-ugly gstreamer1.0-pulseaudio gvfs-backends ibus-gtk3 ibus-libpinyin im-config img2pdf imv initramfs-tools installation-birthday iptables jupyter jupyter-nbextension-jupyter-js-widgets keyboard-configuration krb5-locales kwin-x11 lintian linux-image-amd64 linux-perf lmodern lsb-base lvm2 mailscripts mailutils mate-themes mime-support mpdris2 mupdf ncal npm2deb ntfs-3g nvme-cli okular-extra-backends openstack-clients plymouth plymouth-themes popularity-contest progress prometheus-node-exporter psensor pubpaste pulseaudio python3-ldap ruby ruby-dev rygel-playbin rygel-tracker sanoid scrcpy-server sddm smartmontools sound-theme-freedesktop strongswan strongswan-swanctl syncthing system-config-printer-udev systemd-bootchart systemd-container task-desktop task-english task-ssh-server texinfo texlive-fonts-extra texlive-lang-german texlive-lang-italian texlive-xetex thunar-archive-plugin tidy tipa trocla ucf udisks2 unifont upower usbguard uuid-runtime virt-manager wireshark xapian-tools xclip xserver-xorg xsltproc xz-utils zathura zathura-pdf-poppler zfs-dkms zfs-initramfs zfsutils-linux zlib1g zlib1g-dev

Yuck! That's a lot of shit to go through.

Notice how the packages get sorted between "old" and "new" packages. This is because popcon is used as a tool to mark which packages are "old". If you have unmanaged packages, the "old" ones are likely things that you can uninstall, for example.

If you don't have popcon installed, you'll also get this warning:

popcon stats not available: [Errno 2] No such file or directory: '/var/log/popularity-contest'

The error can otherwise be safely ignored, but you won't get "help" prioritizing the packages to add to your manifests.

Note that the tool ignores packages that were "marked" (see apt-mark(8)) as automatically installed. This implies that you might have to do a little bit of cleanup the first time you run this, as Debian doesn't necessarily mark all of those packages correctly on first install. For example, here's how it looks like on a clean install, after Puppet ran:

root@angela:/home/anarcat# ./bin/puppet-package-check -v
listing puppet packages...
listing apt packages...
loading apt cache...
127 unmanaged packages found
ca-certificates console-setup cryptsetup-initramfs dbus file gcc-12-base gettext-base grub-common grub-efi-amd64 i3lock initramfs-tools iw keyboard-configuration krb5-locales laptop-detect libacl1 libapparmor1 libapt-pkg6.0 libargon2-1 libattr1 libaudit-common libaudit1 libblkid1 libbpf0 libbsd0 libbz2-1.0 libc6 libcap-ng0 libcap2 libcap2-bin libcom-err2 libcrypt1 libcryptsetup12 libdb5.3 libdebconfclient0 libdevmapper1.02.1 libedit2 libelf1 libext2fs2 libfdisk1 libffi8 libgcc-s1 libgcrypt20 libgmp10 libgnutls30 libgpg-error0 libgssapi-krb5-2 libhogweed6 libidn2-0 libip4tc2 libiw30 libjansson4 libjson-c5 libk5crypto3 libkeyutils1 libkmod2 libkrb5-3 libkrb5support0 liblocale-gettext-perl liblockfile-bin liblz4-1 liblzma5 libmd0 libmnl0 libmount1 libncurses6 libncursesw6 libnettle8 libnewt0.52 libnftables1 libnftnl11 libnl-3-200 libnl-genl-3-200 libnl-route-3-200 libnss-systemd libp11-kit0 libpam-systemd libpam0g libpcre2-8-0 libpcre3 libpcsclite1 libpopt0 libprocps8 libreadline8 libselinux1 libsemanage-common libsemanage2 libsepol2 libslang2 libsmartcols1 libss2 libssl1.1 libssl3 libstdc++6 libsystemd-shared libsystemd0 libtasn1-6 libtext-charwidth-perl libtext-iconv-perl libtext-wrapi18n-perl libtinfo6 libtirpc-common libtirpc3 libudev1 libunistring2 libuuid1 libxtables12 libxxhash0 libzstd1 linux-image-amd64 logsave lsb-base lvm2 media-types mlocate ncurses-term pass-extension-otp puppet python3-reportbug shim-signed tasksel ucf usr-is-merged util-linux-extra wpasupplicant xorg zlib1g
popcon stats not available: [Errno 2] No such file or directory: '/var/log/popularity-contest'

Normally, there should be unmanaged packages here. But because of the way Debian is installed, a lot of libraries and some core packages are marked as manually installed, and are of course not managed through Puppet. There are two solutions to this problem:

  • really manage everything in Puppet (argh)
  • mark packages as automatically installed

I typically chose the second path and mark a ton of stuff as automatic. Then either they will be auto-removed, or will stop being listed. In the above scenario, one could mark all libraries as automatically installed with:

apt-mark auto $(./bin/puppet-package-check | grep -o 'lib[^ ]*')

... but if you trust that most of that stuff is actually garbage that you don't really want installed anyways, you could just mark it all as automatically installed:

apt-mark auto $(./bin/puppet-package-check)

In my case, that ended up keeping basically all libraries (because of course they're installed for some reason) and auto-removing this:

dh-dkms discover-data dkms libdiscover2 libjsoncpp25 libssl1.1 linux-headers-amd64 mlocate pass-extension-otp pass-otp plocate x11-apps x11-session-utils xinit xorg

You'll notice xorg in there: yep, that's bad. Not what I wanted. But for some reason, on other workstations, I did not actually have xorg installed. Turns out having xserver-xorg is enough, and that one has dependencies. So now I guess I just learned to stop worrying and live without X(org).

Optimizing large package installs

But that, of course, is not all. Why make things simple when you can have an unreadable title that is trying to be both syntactically correct and click-baity enough to flatter my vain ego? Right.

One of the challenges in bootstrapping Puppet with large package lists is that it's slow. Puppet lists packages as individual resources and will basically run apt install $PKG on every package in the manifest, one at a time. While the overhead of apt is generally small, when you add things like apt-listbugs, apt-listchanges, needrestart, triggers and so on, it can take forever setting up a new host.

So for initial installs, it can actually makes sense to skip the queue and just install everything in one big batch.

And because the above tool inspects the packages installed by Puppet, you can run it against a catalog and have a full lists of all the packages Puppet would install, even before I even had Puppet running.

So when reinstalling my laptop, I basically did this:

apt install puppet-agent/experimental
puppet agent --test --noop
apt install $(./puppet-package-check --debug \
    2>&1 | grep ^puppet\ packages 
    | sed 's/puppet packages://;s/ /\n/g'
    | grep -v -e onionshare -e golint -e git-sizer -e github-backup -e hledger -e xsane -e audacity -e chirp -e elpa-flycheck -e elpa-lsp-ui -e yubikey-manager -e git-annex -e hopenpgp-tools -e puppet
) puppet-agent/experimental

That massive grep was because there are currently a lot of packages missing from bookworm. Those are all packages that I have in my catalog but that still haven't made it to bookworm. Sad, I know. I eventually worked around that by adding bullseye sources so that the Puppet manifest actually ran.

The point here is that this improves the Puppet run time a lot. All packages get installed at once, and you get a nice progress bar. Then you actually run Puppet to deploy configurations and all the other goodies:

puppet agent --test

I wish I could tell you how much faster that ran. I don't know, and I will not go through a full reinstall just to please your curiosity. The only hard number I have is that it installed 444 packages (which exploded in 10,191 packages with dependencies) in a mere 10 minutes. That might also be with the packages already downloaded.

In any case, I have that gut feeling it's faster, so you'll have to just trust my gut. It is, after all, much more important than you might think.

Similar work

The blueprint system is something similar to this:

It figures out what you’ve done manually, stores it locally in a Git repository, generates code that’s able to recreate your efforts, and helps you deploy those changes to production

That tool has unfortunately been abandoned for a decade at this point.

Also note that the AutoRemove::RecommendsImportant and AutoRemove::SuggestsImportant are relevant here. If it is set to true (the default), a package will not be removed if it is (respectively) a Recommends or Suggests of another package (as opposed to the normal Depends). In other words, if you want to also auto-remove packages that are only Suggests, you would, for example, add this to apt.conf:

AutoRemove::SuggestsImportant false;

Paul Wise has tried to make the Debian installer and debootstrap properly mark packages as automatically installed in the past, but his bug reports were rejected. The other suggestions in this section are also from Paul, thanks!

29 September, 2022 07:05PM

Russell Coker

September 28, 2022

Ian Jackson

Hippotat (IP over HTTP) - first advertised release

I have released version 1.0.0 of Hippotat, my IP-over-HTTP system. To quote the README:

You’re in a cafe or a hotel, trying to use the provided wifi. But it’s not working. You discover that port 80 and port 443 are open, but the wifi forbids all other traffic.

Never mind, start up your hippotat client. Now you have connectivity. Your VPN and SSH and so on run over Hippotat. The result is not very efficient, but it does work.

Story

In early 2017 I was in a mountaintop cafeteria, hoping to do some work on my laptop. (For Reasons I couldn’t go skiing that day.) I found that local wifi was badly broken: It had a severe port block. I had to use my port 443 SSH server to get anywhere. My usual arrangements punt everything over my VPN, which uses UDP of course, and I had to bodge several things. Using a web browser directly only the wifi worked normally, of course - otherwise the other guests would have complained. This was not the first experience like this I’d had, but this time I had nothing much else to do but fix it.

In a few furious hacking sessions, I wrote Hippotat, a tool for making my traffic look enough like “ordinary web browsing” that it gets through most stupid firewalls. That Python version of Hippotat served me well for many years, despite being rather shonky, extremely inefficient in CPU (and therefore battery) terms and not very productised.

But recently things have started to go wrong. I was using Twisted Python and there was what I think must be some kind of buffer handling bug, which started happening when I upgraded the OS (getting newer versions of Python and the Twisted libraries). The Hippotat code, and the Twisted APIs, were quite convoluted, and I didn’t fancy debugging it.

So last year I rewrote it in Rust. The new Rust client did very well against my existing servers. To my shame, I didn’t get around to releasing it.

However, more recently I upgraded the server hosts my Hippotat daemons run on to recent Debian releases. They started to be affected by the bug too, rendering my Rust client unuseable. I decided I had to deploy the Rust server code.

This involved some packaging work. Having done that, it’s time to release it: Hippotat 1.0.0 is out.

The package build instructions are rather strange

My usual approach to releasing something like this would be to provide a git repository containing a proper Debian source package. I might also build binaries, using sbuild, and I would consider actually uploading to Debian.

However, despite me taking a fairly conservative approach to adding dependencies to Hippotat, still a couple of the (not very unusual) Rust packages that Hippotat depends on are not in Debian. Last year I considered tackling this head-on, but I got derailed by difficulties with Rust packaging in Debian.

Furthermore, the version of the Rust compiler itself in Debian stable is incapable of dealing with recent versions of very many upstream Rust packages, because many packages’ most recent versions now require the 2021 Edition of Rust. Sadly, Rust’s package manager, cargo, has no mechanism for trying to choose dependency versions that are actually compatible with the available compiler; efforts to solve this problem have still not borne the needed fruit.

The result is that, in practice, currently Hippotat has to be built with (a) a reasonably recent Rust toolchain such as found in Debian unstable or obtained from Rust upstream; (b) dependencies obtained from the upstream Rust repository.

At least things aren’t completely terrible: Rustup itself, despite its alarming install rune, has a pretty good story around integrity, release key management and so on. And with the right build rune, cargo will check not just the versions, but the precise content hashes, of the dependencies to be obtained from crates.io, against the information I provide in the Cargo.lock file. So at least when you build it you can be sure that the dependencies you’re getting are the same ones I used myself when I built and tested Hippotat. And there’s only 147 of them (counting indirect dependencies too), so what could possibly go wrong?

Sadly the resulting package build system cannot work with Debian’s best tool for doing clean and controlled builds, sbuild. Under the circumstances, I don’t feel I want to publish any binaries.



comment count unavailable comments

28 September, 2022 08:12PM

Vincent Fourmond

Version 3.1 of QSoas is out

The new version of QSoas has just been released ! It brings in a host of new features, as the releases before, but maybe the most important change is the following...

Binary images now freely available !

Starting from now, all the binary images for the new versions of QSoas will freely available from the download page. You can download the precompiled versions of QSoas for MacOS or windows. So now, you have no reason anymore not to try !
My aim with making the binaries freely available is also to simplify the release process for me and therefore increase the rate at which new versions are released.

Improvements to the fit interface

Some work went into improving the fit interface, in particular for the handling of fit trajectories when doing parameter space exploration, for difficult fits with many parameters and many local minima. The fit window now features real menus, along with tab a way to display the terminal (see the menus and the tabs selection on the image).
Individual fits have also been improved, with, among others, the possibility to easily simulate voltammograms with the kinetic-system fits, and the handling of Marcus-Hush-Chidsey (or Marcus "distribution of states") kinetics for electron transfers.

Column and row names

This release greatly improves the handling of column and row names, including commands to easily modify them, the possibility to use Ruby formulas to change them, and a much better way read and write them to data files. Mastering the use of column names (and to a lesser extent, row names) can greatly simplify data handling, especially when dealing with files with a large number of columns.

Complex numbers

Version 3.1 brings in support for formulas handling complex numbers. Although it is not possible to store complex numbers directly into datasets, it is easy to separate them in real and imaginary parts to your liking.

Scripting improvement

Two important improvements for scripting are included in version 3.1. The first is the possibility to define virtual files inside a script file, which makes it easy to define subfunctions to run using commands like run-for-each. The second is the possibility to define variables to be reused later (like the script arguments) using the new command let.

There are a lot of other new features, improvements and so on, look for the full list there.

About QSoas


QSoas is a powerful open source data analysis program that focuses on flexibility and powerful fitting capacities. It is released under the GNU General Public License. It is described in Fourmond, Anal. Chem., 2016, 88 (10), pp 5050–5052. Current version is 3.1. You can download its source code or precompiled versions for MacOS and Windows there. Alternatively, you can clone from the GitHub repository.

28 September, 2022 01:29PM by Vincent Fourmond (noreply@blogger.com)

September 27, 2022

François Marier

Upgrading from chan_sip to res_pjsip in Asterisk 18

After upgrading to Ubuntu Jammy and Asterisk 18.10, I saw the following messages in my logs:

WARNING[360166]: loader.c:2487 in load_modules: Module 'chan_sip' has been loaded but was deprecated in Asterisk version 17 and will be removed in Asterisk version 21.
WARNING[360174]: chan_sip.c:35468 in deprecation_notice: chan_sip has no official maintainer and is deprecated.  Migration to
WARNING[360174]: chan_sip.c:35469 in deprecation_notice: chan_pjsip is recommended.  See guides at the Asterisk Wiki:
WARNING[360174]: chan_sip.c:35470 in deprecation_notice: https://wiki.asterisk.org/wiki/display/AST/Migrating+from+chan_sip+to+res_pjsip
WARNING[360174]: chan_sip.c:35471 in deprecation_notice: https://wiki.asterisk.org/wiki/display/AST/Configuring+res_pjsip

and so I decided it was time to stop postponing the overdue migration of my working setup from chan_sip to res_pjsip.

It turns out that it was not as painful as I expected, though the conversion script bundled with Asterisk didn't work for me out of the box.

Debugging

Before you start, one very important thing to note is that the SIP debug information you used to see when running this in the asterisk console (asterisk -r):

sip set debug on

now lives behind this command:

pjsip set logger on

SIP phones

The first thing I migrated was the config for my two SIP phones (Snom 300 and Snom D715).

The original config for them in sip.conf was:

[2000]
; Snom 300
type=friend
qualify=yes
secret=password123
encryption=no
context=full
host=dynamic
nat=no
directmedia=no
mailbox=10@internal
vmexten=707
dtmfmode=rfc2833
call-limit=2
disallow=all
allow=g722
allow=ulaw

[2001]
; Snom D715
type=friend
qualify=yes
secret=password456
encryption=no
context=full
host=dynamic
nat=no
directmedia=yes
mailbox=10@internal
vmexten=707
dtmfmode=rfc2833
call-limit=2
disallow=all
allow=g722
allow=ulaw

and that became the following in pjsip.conf:

[transport-udp]
type = transport
protocol = udp
bind = 0.0.0.0
external_media_address = myasterisk.dyn.example.com
external_signaling_address = myasterisk.dyn.example.com
local_net = 192.168.0.0/255.255.0.0

[2000]
type = aor
max_contacts = 1

[2000]
type = auth
username = 2000
password = password123

[2000]
type = endpoint
context = full
dtmf_mode = rfc4733
disallow = all
allow = g722
allow = ulaw
direct_media = no
mailboxes = 10@internal
auth = 2000
outbound_auth = 2000
aors = 2000

[2001]
type = aor
max_contacts = 1

[2001]
type = auth
username = 2001
password = password456

[2001]
type = endpoint
context = full
dtmf_mode = rfc4733
disallow = all
allow = g722
allow = ulaw
direct_media = yes
mailboxes = 10@internal
auth = 2001
outbound_auth = 2001
aors = 2001

The different direct_media line between the two phones has to do with how they each connect to my Asterisk server and whether or not they have access to the Internet.

Internal calls

For some reason, my internal calls (from one SIP phone to the other) didn't work when using "aliases". I fixed it by changing this blurb in extensions.conf from:

[speeddial]
exten => 1000,1,Dial(SIP/2000,20)
exten => 1001,1,Dial(SIP/2001,20)

to:

[speeddial]
exten => 1000,1,Dial(${PJSIP_DIAL_CONTACTS(2000)},20)
exten => 1001,1,Dial(${PJSIP_DIAL_CONTACTS(2001)},20)

I have not yet dug into what this changes or why it's necessary and so feel free to leave a comment if you know more here.

PSTN trunk

Once I had the internal phones working, I moved to making and receiving phone calls over the PSTN, for which I use VoIP.ms with encryption.

I had to change the following in my sip.conf:

[general]
register => tls://555123_myasterisk:password789@vancouver2.voip.ms
externhost=myasterisk.dyn.example.com
localnet=192.168.0.0/255.255.0.0
tcpenable=yes
tlsenable=yes
tlscertfile=/etc/asterisk/asterisk.cert
tlsprivatekey=/etc/asterisk/asterisk.key
tlscapath=/etc/ssl/certs/

[voipms]
type=peer
host=vancouver2.voip.ms
secret=password789
defaultuser=555123_myasterisk
context=from-voipms
disallow=all
allow=ulaw
allow=g729
insecure=port,invite
canreinvite=no
trustrpid=yes
sendrpid=yes
transport=tls
encryption=yes

to the following in pjsip.conf:

[transport-tls]
type = transport
protocol = tls
bind = 0.0.0.0
external_media_address = myasterisk.dyn.example.com
external_signaling_address = myasterisk.dyn.example.com
local_net = 192.168.0.0/255.255.0.0
cert_file = /etc/asterisk/asterisk.cert
priv_key_file = /etc/asterisk/asterisk.key
ca_list_path = /etc/ssl/certs/
method = tlsv1_2

[voipms]
type = registration
transport = transport-tls
outbound_auth = voipms
client_uri = sip:555123_myasterisk@vancouver2.voip.ms
server_uri = sip:vancouver2.voip.ms

[voipms]
type = auth
password = password789
username = 555123_myasterisk

[voipms]
type = aor
contact = sip:555123_myasterisk@vancouver2.voip.ms

[voipms]
type = identify
endpoint = voipms
match = vancouver2.voip.ms

[voipms]
type = endpoint
context = from-voipms
disallow = all
allow = ulaw
allow = g729
from_user = 555123_myasterisk
trust_id_inbound = yes
media_encryption = sdes
auth = voipms
outbound_auth = voipms
aors = voipms
rtp_symmetric = yes
rewrite_contact = yes
send_rpid = yes
timers = no

The TLS method line is needed since the default in Debian OpenSSL is too strict. The timers line is to prevent outbound calls from getting dropped after 15 minutes.

Finally, I changed the Dial() lines in these extensions.conf blurbs from:

[from-voipms]
exten => 5551231000,1,Goto(2000,1)
exten => 2000,1,Dial(SIP/2000&SIP/2001,20)
exten => 2000,n,Goto(in2000-${DIALSTATUS},1)
exten => 2000,n,Hangup
exten => in2000-BUSY,1,VoiceMail(10@internal,su)
exten => in2000-BUSY,n,Hangup
exten => in2000-CONGESTION,1,VoiceMail(10@internal,su)
exten => in2000-CONGESTION,n,Hangup
exten => in2000-CHANUNAVAIL,1,VoiceMail(10@internal,su)
exten => in2000-CHANUNAVAIL,n,Hangup
exten => in2000-NOANSWER,1,VoiceMail(10@internal,su)
exten => in2000-NOANSWER,n,Hangup
exten => _in2000-.,1,Hangup(16)

[pstn-voipms]
exten => _1NXXNXXXXXX,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _1NXXNXXXXXX,n,Dial(SIP/voipms/${EXTEN})
exten => _1NXXNXXXXXX,n,Hangup()
exten => _NXXNXXXXXX,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _NXXNXXXXXX,n,Dial(SIP/voipms/1${EXTEN})
exten => _NXXNXXXXXX,n,Hangup()
exten => _011X.,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _011X.,n,Authenticate(1234)
exten => _011X.,n,Dial(SIP/voipms/${EXTEN})
exten => _011X.,n,Hangup()
exten => _00X.,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _00X.,n,Authenticate(1234)
exten => _00X.,n,Dial(SIP/voipms/${EXTEN})
exten => _00X.,n,Hangup()

to:

[from-voipms]
exten => 5551231000,1,Goto(2000,1)
exten => 2000,1,Dial(PJSIP/2000&PJSIP/2001,20)
exten => 2000,n,Goto(in2000-${DIALSTATUS},1)
exten => 2000,n,Hangup
exten => in2000-BUSY,1,VoiceMail(10@internal,su)
exten => in2000-BUSY,n,Hangup
exten => in2000-CONGESTION,1,VoiceMail(10@internal,su)
exten => in2000-CONGESTION,n,Hangup
exten => in2000-CHANUNAVAIL,1,VoiceMail(10@internal,su)
exten => in2000-CHANUNAVAIL,n,Hangup
exten => in2000-NOANSWER,1,VoiceMail(10@internal,su)
exten => in2000-NOANSWER,n,Hangup
exten => _in2000-.,1,Hangup(16)

[pstn-voipms]
exten => _1NXXNXXXXXX,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _1NXXNXXXXXX,n,Dial(PJSIP/${EXTEN}@voipms)
exten => _1NXXNXXXXXX,n,Hangup()
exten => _NXXNXXXXXX,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _NXXNXXXXXX,n,Dial(PJSIP/1${EXTEN}@voipms)
exten => _NXXNXXXXXX,n,Hangup()
exten => _011X.,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _011X.,n,Authenticate(1234)
exten => _011X.,n,Dial(PJSIP/${EXTEN}@voipms)
exten => _011X.,n,Hangup()
exten => _00X.,1,Set(CALLERID(all)=Francois Marier <5551231000>)
exten => _00X.,n,Authenticate(1234)
exten => _00X.,n,Dial(PJSIP/${EXTEN}@voipms)
exten => _00X.,n,Hangup()

Note that it's not just replacing SIP/ with PJSIP/, but it was also necessary to use a format supported by pjsip for the channel since SIP/trunkname/extension isn't supported by pjsip.

27 September, 2022 11:30PM

hackergotchi for Steve McIntyre

Steve McIntyre

Firmware again - updates, how I'm voting and why!

Updates

Back in April I wrote about issues with how we handle firmware in Debian, and I also spoke about it at DebConf in July. Since then, we've started the General Resolution process - this led to a lot of discussion on the the debian-vote mailing list and we're now into the second week of the voting phase.

The discussion has caught the interest of a few news sites along the way:

My vote

I've also had several people ask me how I'm voting myself, as I started this GR in the first place. I'm happy to oblige! Here's my vote, sorted into preference order:

  [1] Choice 5: Change SC for non-free firmware in installer, one installer
  [2] Choice 1: Only one installer, including non-free firmware
  [3] Choice 6: Change SC for non-free firmware in installer, keep both installers
  [4] Choice 2: Recommend installer containing non-free firmware
  [5] Choice 3: Allow presenting non-free installers alongside the free one
  [6] Choice 7: None Of The Above
  [7] Choice 4: Installer with non-free software is not part of Debian

Why have I voted this way?

Fundamentally, my motivation for starting this vote was to ask the project for clear positive direction on a sensible way forward with non-free firmware support. Thus, I've voted all of the options that do that above NOTA. On those terms, I don't like Choice 4 here - IMHO it leaves us in the same unclear situation as before.

I'd be happy for us to update the Social Contract for clarity, and I know some people would be much more comfortable if we do that explicitly here. Choice 1 was my initial personal preference as we started the GR, but since then I've been convinced that also updating the SC would be a good idea, hence Choice 5.

I'd also rather have a single image / set of images produced, for the two reasons I've outlined before. It's less work for our images team to build and test all the options. But, much more importantly: I believe it's less likely to confuse new users.

I appreciate that not everybody agrees with me here, and this is part of the reason why we're voting!

Other Debian people have also blogged about their voting choices (Gunnar Wolf and Ian Jackson so far), and I thank them for sharing their reasoning too.

For the avoidance of doubt: my goal for this vote was simply to get a clear direction on how to proceed here. Although I proposed Choice 1 (Only one installer, including non-free firmware), I also seconded several of the other ballot options. Of course I will accept the will of the project when the result is announced - I'm not going to do anything silly like throw a tantrum or quit the project over this!

Finally

If you're a DD and you haven't voted already, please do so - this is an important choice for the Debian project.

27 September, 2022 05:46PM

September 26, 2022

Jelmer Vernooij

Northcape 4000

This summer, I signed up to participate in the Northcape 4000 <https://www.northcape4000.com/>, an annual 4000km bike ride between Rovereto (in northern Italy) and the northernmost point of Europe, the North cape.

The Northcape event has been held for several years, and while it always ends on the North Cape, the route there varies. Last years’ route went through the Baltics, but this years’ was perhaps as direct as possible - taking us through Italy, Austria, Switzerland, Germany, the Czech republic, Germany again, Sweden, Finland and finally Norway.

The ride is unsupported, meaning you have to find your own food and accomodation and can only avail yourself of resupply and sleeping options on the route that are available to everybody else as well. The event is not meant to be a race (unlike the Transcontinental, which starts at the same day), so there is a minimum time to finish it in (10 days) and a maximum (21 days).

Unfortunately, this meant skipping some other events I’d wanted attend (DebConf, MCH).

26 September, 2022 10:00PM by Jelmer Vernooj

hackergotchi for Bits from Debian

Bits from Debian

New Debian Developers and Maintainers (July and August 2022)

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

  • Sakirnth Nagarasa (sakirnth)
  • Philip Rinn (rinni)
  • Arnaud Rebillout (arnaudr)
  • Marcos Talau (talau)

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

  • Xiao Sheng Wen
  • Andrea Pappacoda
  • Robin Jarry
  • Ben Westover
  • Michel Alexandre Salim

Congratulations!

26 September, 2022 02:00PM by Jean-Pierre Giraud

September 25, 2022

hackergotchi for Sergio Talens-Oliag

Sergio Talens-Oliag

Kubernetes Static Content Server

This post describes how I’ve put together a simple static content server for kubernetes clusters using a Pod with a persistent volume and multiple containers: an sftp server to manage contents, a web server to publish them with optional access control and another one to run scripts which need access to the volume filesystem.

The sftp server runs using MySecureShell, the web server is nginx and the script runner uses the webhook tool to publish endpoints to call them (the calls will come from other Pods that run backend servers or are executed from Jobs or CronJobs).

History

The system was developed because we had a NodeJS API with endpoints to upload files and store them on S3 compatible services that were later accessed via HTTPS, but the requirements changed and we needed to be able to publish folders instead of individual files using their original names and apply access restrictions using our API.

Thinking about our requirements the use of a regular filesystem to keep the files and folders was a good option, as uploading and serving files is simple.

For the upload I decided to use the sftp protocol, mainly because I already had an sftp container image based on mysecureshell prepared; once we settled on that we added sftp support to the API server and configured it to upload the files to our server instead of using S3 buckets.

To publish the files we added a nginx container configured to work as a reverse proxy that uses the ngx_http_auth_request_module to validate access to the files (the sub request is configurable, in our deployment we have configured it to call our API to check if the user can access a given URL).

Finally we added a third container when we needed to execute some tasks directly on the filesystem (using kubectl exec with the existing containers did not seem a good idea, as that is not supported by CronJobs objects, for example).

The solution we found avoiding the NIH Syndrome (i.e. write our own tool) was to use the webhook tool to provide the endpoints to call the scripts; for now we have three:

  • one to get the disc usage of a PATH,
  • one to hardlink all the files that are identical on the filesystem,
  • one to copy files and folders from S3 buckets to our filesystem.

Container definitions

mysecureshell

The mysecureshell container can be used to provide an sftp service with multiple users (although the files are owned by the same UID and GID) using standalone containers (launched with docker or podman) or in an orchestration system like kubernetes, as we are going to do here.

The image is generated using the following Dockerfile:

ARG ALPINE_VERSION=3.16.2

FROM alpine:$ALPINE_VERSION as builder
LABEL maintainer="Sergio Talens-Oliag <sto@mixinet.net>"
RUN apk update &&\
 apk add --no-cache alpine-sdk git musl-dev &&\
 git clone https://github.com/sto/mysecureshell.git &&\
 cd mysecureshell &&\
 ./configure --prefix=/usr --sysconfdir=/etc --mandir=/usr/share/man\
 --localstatedir=/var --with-shutfile=/var/lib/misc/sftp.shut --with-debug=2 &&\
 make all && make install &&\
 rm -rf /var/cache/apk/*

FROM alpine:$ALPINE_VERSION
LABEL maintainer="Sergio Talens-Oliag <sto@mixinet.net>"
COPY --from=builder /usr/bin/mysecureshell /usr/bin/mysecureshell
COPY --from=builder /usr/bin/sftp-* /usr/bin/
RUN apk update &&\
 apk add --no-cache openssh shadow pwgen &&\
 sed -i -e "s|^.*\(AuthorizedKeysFile\).*$|\1 /etc/ssh/auth_keys/%u|"\
 /etc/ssh/sshd_config &&\
 mkdir /etc/ssh/auth_keys &&\
 cat /dev/null > /etc/motd &&\
 add-shell '/usr/bin/mysecureshell' &&\
 rm -rf /var/cache/apk/*
COPY bin/* /usr/local/bin/
COPY etc/sftp_config /etc/ssh/
COPY entrypoint.sh /
EXPOSE 22
VOLUME /sftp
ENTRYPOINT ["/entrypoint.sh"]
CMD ["server"]

The /etc/sftp_config file is used to configure the mysecureshell server to have all the user homes under /sftp/data, only allow them to see the files under their home directories as if it were at the root of the server and close idle connections after 5m of inactivity:

etc/sftp_config 
# Default mysecureshell configuration
<Default>
   # All users will have access their home directory under /sftp/data
   Home /sftp/data/$USER
   # Log to a file inside /sftp/logs/ (only works when the directory exists)
   LogFile /sftp/logs/mysecureshell.log
   # Force users to stay in their home directory
   StayAtHome true
   # Hide Home PATH, it will be shown as /
   VirtualChroot true
   # Hide real file/directory owner (just change displayed permissions)
   DirFakeUser true
   # Hide real file/directory group (just change displayed permissions)
   DirFakeGroup true
   # We do not want users to keep forever their idle connection
   IdleTimeOut 5m
</Default>
# vim: ts=2:sw=2:et

The entrypoint.sh script is the one responsible to prepare the container for the users included on the /secrets/user_pass.txt file (creates the users with their HOME directories under /sftp/data and a /bin/false shell and creates the key files from /secrets/user_keys.txt if available).

The script expects a couple of environment variables:

  • SFTP_UID: UID used to run the daemon and for all the files, it has to be different than 0 (all the files managed by this daemon are going to be owned by the same user and group, even if the remote users are different).
  • SFTP_GID: GID used to run the daemon and for all the files, it has to be different than 0.

And can use the SSH_PORT and SSH_PARAMS values if present.

It also requires the following files (they can be mounted as secrets in kubernetes):

  • /secrets/host_keys.txt: Text file containing the ssh server keys in mime format; the file is processed using the reformime utility (the one included on busybox) and can be generated using the gen-host-keys script included on the container (it uses ssh-keygen and makemime).
  • /secrets/user_pass.txt: Text file containing lines of the form username:password_in_clear_text (only the users included on this file are available on the sftp server, in fact in our deployment we use only the scs user for everything).

And optionally can use another one:

  • /secrets/user_keys.txt: Text file that contains lines of the form username:public_ssh_ed25519_or_rsa_key; the public keys are installed on the server and can be used to log into the sftp server if the username exists on the user_pass.txt file.

The contents of the entrypoint.sh script are:

entrypoint.sh 
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
# Expects SSH_UID & SSH_GID on the environment and uses the value of the
# SSH_PORT & SSH_PARAMS variables if present
# SSH_PARAMS
SSH_PARAMS="-D -e -p ${SSH_PORT:=22} ${SSH_PARAMS}"
# Fixed values
# DIRECTORIES
HOME_DIR="/sftp/data"
CONF_FILES_DIR="/secrets"
AUTH_KEYS_PATH="/etc/ssh/auth_keys"
# FILES
HOST_KEYS="$CONF_FILES_DIR/host_keys.txt"
USER_KEYS="$CONF_FILES_DIR/user_keys.txt"
USER_PASS="$CONF_FILES_DIR/user_pass.txt"
USER_SHELL_CMD="/usr/bin/mysecureshell"
# TYPES
HOST_KEY_TYPES="dsa ecdsa ed25519 rsa"
# ---------
# FUNCTIONS
# ---------
# Validate HOST_KEYS, USER_PASS, SFTP_UID and SFTP_GID
_check_environment() {
  # Check the ssh server keys ... we don't boot if we don't have them
  if [ ! -f "$HOST_KEYS" ]; then
    cat <<EOF
We need the host keys on the '$HOST_KEYS' file to proceed.

Call the 'gen-host-keys' script to create and export them on a mime file.
EOF
    exit 1
  fi
  # Check that we have users ... if we don't we can't continue
  if [ ! -f "$USER_PASS" ]; then
    cat <<EOF
We need at least the '$USER_PASS' file to provision users.

Call the 'gen-users-tar' script to create a tar file to create an archive that
contains public and private keys for users, a 'user_keys.txt' with the public
keys of the users and a 'user_pass.txt' file with random passwords for them 
(pass the list of usernames to it).
EOF
    exit 1
  fi
  # Check SFTP_UID
  if [ -z "$SFTP_UID" ]; then
    echo "The 'SFTP_UID' can't be empty, pass a 'GID'."
    exit 1
  fi
  if [ "$SFTP_UID" -eq "0" ]; then
    echo "The 'SFTP_UID' can't be 0, use a different 'UID'"
    exit 1
  fi
  # Check SFTP_GID
  if [ -z "$SFTP_GID" ]; then
    echo "The 'SFTP_GID' can't be empty, pass a 'GID'."
    exit 1
  fi
  if [ "$SFTP_GID" -eq "0" ]; then
    echo "The 'SFTP_GID' can't be 0, use a different 'GID'"
    exit 1
  fi
}
# Adjust ssh host keys
_setup_host_keys() {
  opwd="$(pwd)"
  tmpdir="$(mktemp -d)"
  cd "$tmpdir"
  ret="0"
  reformime <"$HOST_KEYS" || ret="1"
  for kt in $HOST_KEY_TYPES; do
    key="ssh_host_${kt}_key"
    pub="ssh_host_${kt}_key.pub"
    if [ ! -f "$key" ]; then
      echo "Missing '$key' file"
      ret="1"
    fi
    if [ ! -f "$pub" ]; then
      echo "Missing '$pub' file"
      ret="1"
    fi
    if [ "$ret" -ne "0" ]; then
      continue
    fi
    cat "$key" >"/etc/ssh/$key"
    chmod 0600 "/etc/ssh/$key"
    chown root:root "/etc/ssh/$key"
    cat "$pub" >"/etc/ssh/$pub"
    chmod 0600 "/etc/ssh/$pub"
    chown root:root "/etc/ssh/$pub"
  done
  cd "$opwd"
  rm -rf "$tmpdir"
  return "$ret"
}
# Create users
_setup_user_pass() {
  opwd="$(pwd)"
  tmpdir="$(mktemp -d)"
  cd "$tmpdir"
  ret="0"
  [ -d "$HOME_DIR" ] || mkdir "$HOME_DIR"
  # Make sure the data dir can be managed by the sftp user
  chown "$SFTP_UID:$SFTP_GID" "$HOME_DIR"
  # Allow the user (and root) to create directories inside the $HOME_DIR, if
  # we don't allow it the directory creation fails on EFS (AWS)
  chmod 0755 "$HOME_DIR"
  # Create users
  echo "sftp:sftp:$SFTP_UID:$SFTP_GID:::/bin/false" >"newusers.txt"
  sed -n "/^[^#]/ { s/:/ /p }" "$USER_PASS" | while read -r _u _p; do
    echo "$_u:$_p:$SFTP_UID:$SFTP_GID::$HOME_DIR/$_u:$USER_SHELL_CMD"
  done >>"newusers.txt"
  newusers --badnames newusers.txt
  # Disable write permission on the directory to forbid remote sftp users to
  # remove their own root dir (they have already done it); we adjust that
  # here to avoid issues with EFS (see before)
  chmod 0555 "$HOME_DIR"
  # Clean up the tmpdir
  cd "$opwd"
  rm -rf "$tmpdir"
  return "$ret"
}
# Adjust user keys
_setup_user_keys() {
  if [ -f "$USER_KEYS" ]; then
    sed -n "/^[^#]/ { s/:/ /p }" "$USER_KEYS" | while read -r _u _k; do
      echo "$_k" >>"$AUTH_KEYS_PATH/$_u"
    done
  fi
}
# Main function
exec_sshd() {
  _check_environment
  _setup_host_keys
  _setup_user_pass
  _setup_user_keys
  echo "Running: /usr/sbin/sshd $SSH_PARAMS"
  # shellcheck disable=SC2086
  exec /usr/sbin/sshd -D $SSH_PARAMS
}
# ----
# MAIN
# ----
case "$1" in
"server") exec_sshd ;;
*) exec "$@" ;;
esac
# vim: ts=2:sw=2:et

The container also includes a couple of auxiliary scripts, the first one can be used to generate the host_keys.txt file as follows:

$ docker run --rm stodh/mysecureshell gen-host-keys > host_keys.txt

Where the script is as simple as:

bin/gen-host-keys 
#!/bin/sh
set -e
# Generate new host keys
ssh-keygen -A >/dev/null
# Replace hostname
sed -i -e 's/@.*$/@mysecureshell/' /etc/ssh/ssh_host_*_key.pub
# Print in mime format (stdout)
makemime /etc/ssh/ssh_host_*
# vim: ts=2:sw=2:et

And there is another script to generate a .tar file that contains auth data for the list of usernames passed to it (the file contains a user_pass.txt file with random passwords for the users, public and private ssh keys for them and the user_keys.txt file that matches the generated keys).

To generate a tar file for the user scs we can execute the following:

$ docker run --rm stodh/mysecureshell gen-users-tar scs > /tmp/scs-users.tar

To see the contents and the text inside the user_pass.txt file we can do:

$ tar tvf /tmp/scs-users.tar
-rw-r--r-- root/root        21 2022-09-11 15:55 user_pass.txt
-rw-r--r-- root/root       822 2022-09-11 15:55 user_keys.txt
-rw------- root/root       387 2022-09-11 15:55 id_ed25519-scs
-rw-r--r-- root/root        85 2022-09-11 15:55 id_ed25519-scs.pub
-rw------- root/root      3357 2022-09-11 15:55 id_rsa-scs
-rw------- root/root      3243 2022-09-11 15:55 id_rsa-scs.pem
-rw-r--r-- root/root       729 2022-09-11 15:55 id_rsa-scs.pub
$ tar xfO /tmp/scs-users.tar user_pass.txt
scs:20JertRSX2Eaar4x

The source of the script is:

bin/gen-users-tar 
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
USER_KEYS_FILE="user_keys.txt"
USER_PASS_FILE="user_pass.txt"
# ---------
# MAIN CODE
# ---------
# Generate user passwords and keys, return 1 if no username is received
if [ "$#" -eq "0" ]; then
  return 1
fi
opwd="$(pwd)"
tmpdir="$(mktemp -d)"
cd "$tmpdir"
for u in "$@"; do
  ssh-keygen -q -a 100 -t ed25519 -f "id_ed25519-$u" -C "$u" -N ""
  ssh-keygen -q -a 100 -b 4096 -t rsa -f "id_rsa-$u" -C "$u" -N ""
  # Legacy RSA private key format
  cp -a "id_rsa-$u" "id_rsa-$u.pem"
  ssh-keygen -q -p -m pem -f "id_rsa-$u.pem" -N "" -P "" >/dev/null
  chmod 0600 "id_rsa-$u.pem"
  echo "$u:$(pwgen -s 16 1)" >>"$USER_PASS_FILE"
  echo "$u:$(cat "id_ed25519-$u.pub")" >>"$USER_KEYS_FILE"
  echo "$u:$(cat "id_rsa-$u.pub")" >>"$USER_KEYS_FILE"
done
tar cf - "$USER_PASS_FILE" "$USER_KEYS_FILE" id_* 2>/dev/null
cd "$opwd"
rm -rf "$tmpdir"
# vim: ts=2:sw=2:et

nginx-scs

The nginx-scs container is generated using the following Dockerfile:

ARG NGINX_VERSION=1.23.1

FROM nginx:$NGINX_VERSION
LABEL maintainer="Sergio Talens-Oliag <sto@mixinet.net>"
RUN rm -f /docker-entrypoint.d/*
COPY docker-entrypoint.d/* /docker-entrypoint.d/

Basically we are removing the existing docker-entrypoint.d scripts from the standard image and adding a new one that configures the web server as we want using a couple of environment variables:

  • AUTH_REQUEST_URI: URL to use for the auth_request, if the variable is not found on the environment auth_request is not used.
  • HTML_ROOT: Base directory of the web server, if not passed the default /usr/share/nginx/html is used.

Note that if we don’t pass the variables everything works as if we were using the original nginx image.

The contents of the configuration script are:

docker-entrypoint.d/10-update-default-conf.sh 
#!/bin/sh
# Replace the default.conf nginx file by our own version.
set -e
if [ -z "$HTML_ROOT" ]; then
  HTML_ROOT="/usr/share/nginx/html"
fi
if [ "$AUTH_REQUEST_URI" ]; then
  cat >/etc/nginx/conf.d/default.conf <<EOF
server {
  listen       80;
  server_name  localhost;
  location / {
    auth_request /.auth;
    root  $HTML_ROOT;
    index index.html index.htm;
  }
  location /.auth {
    internal;
    proxy_pass $AUTH_REQUEST_URI;
    proxy_pass_request_body off;
    proxy_set_header Content-Length "";
    proxy_set_header X-Original-URI \$request_uri;
  }
  error_page   500 502 503 504  /50x.html;
  location = /50x.html {
    root /usr/share/nginx/html;
  }
}
EOF
else
  cat >/etc/nginx/conf.d/default.conf <<EOF
server {
  listen       80;
  server_name  localhost;
  location / {
    root  $HTML_ROOT;
    index index.html index.htm;
  }
  error_page   500 502 503 504  /50x.html;
  location = /50x.html {
    root /usr/share/nginx/html;
  }
}
EOF
fi
# vim: ts=2:sw=2:et

As we will see later the idea is to use the /sftp/data or /sftp/data/scs folder as the root of the web published by this container and create an Ingress object to provide access to it outside of our kubernetes cluster.

webhook-scs

The webhook-scs container is generated using the following Dockerfile:

ARG ALPINE_VERSION=3.16.2
ARG GOLANG_VERSION=alpine3.16

FROM golang:$GOLANG_VERSION AS builder
LABEL maintainer="Sergio Talens-Oliag <sto@mixinet.net>"
ENV WEBHOOK_VERSION 2.8.0
ENV WEBHOOK_PR 549
ENV S3FS_VERSION v1.91
WORKDIR /go/src/github.com/adnanh/webhook
RUN apk update &&\
 apk add --no-cache -t build-deps curl libc-dev gcc libgcc patch
RUN curl -L --silent -o webhook.tar.gz\
 https://github.com/adnanh/webhook/archive/${WEBHOOK_VERSION}.tar.gz &&\
 tar xzf webhook.tar.gz --strip 1 &&\
 curl -L --silent -o ${WEBHOOK_PR}.patch\
 https://patch-diff.githubusercontent.com/raw/adnanh/webhook/pull/${WEBHOOK_PR}.patch &&\
 patch -p1 < ${WEBHOOK_PR}.patch &&\
 go get -d && \
 go build -o /usr/local/bin/webhook
WORKDIR /src/s3fs-fuse
RUN apk update &&\
 apk add ca-certificates build-base alpine-sdk libcurl automake autoconf\
 libxml2-dev libressl-dev mailcap fuse-dev curl-dev
RUN curl -L --silent -o s3fs.tar.gz\
 https://github.com/s3fs-fuse/s3fs-fuse/archive/refs/tags/$S3FS_VERSION.tar.gz &&\
 tar xzf s3fs.tar.gz --strip 1 &&\
 ./autogen.sh &&\
 ./configure --prefix=/usr/local &&\
 make -j && \
 make install

FROM alpine:$ALPINE_VERSION
LABEL maintainer="Sergio Talens-Oliag <sto@mixinet.net>"
WORKDIR /webhook
RUN apk update &&\
 apk add --no-cache ca-certificates mailcap fuse libxml2 libcurl libgcc\
 libstdc++ rsync util-linux-misc &&\
 rm -rf /var/cache/apk/*
COPY --from=builder /usr/local/bin/webhook /usr/local/bin/webhook
COPY --from=builder /usr/local/bin/s3fs /usr/local/bin/s3fs
COPY entrypoint.sh /
COPY hooks/* ./hooks/
EXPOSE 9000
ENTRYPOINT ["/entrypoint.sh"]
CMD ["server"]

Again, we use a multi-stage build because in production we wanted to support a functionality that is not already on the official versions (streaming the command output as a response instead of waiting until the execution ends); this time we build the image applying the PATCH included on this pull request against a released version of the source instead of creating a fork.

The entrypoint.sh script is used to generate the webhook configuration file for the existing hooks using environment variables (basically the WEBHOOK_WORKDIR and the *_TOKEN variables) and launch the webhook service:

entrypoint.sh 
#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
WEBHOOK_BIN="${WEBHOOK_BIN:-/webhook/hooks}"
WEBHOOK_YML="${WEBHOOK_YML:-/webhook/scs.yml}"
WEBHOOK_OPTS="${WEBHOOK_OPTS:--verbose}"
# ---------
# FUNCTIONS
# ---------
print_du_yml() {
  cat <<EOF
- id: du
  execute-command: '$WEBHOOK_BIN/du.sh'
  command-working-directory: '$WORKDIR'
  response-headers:
  - name: 'Content-Type'
    value: 'application/json'
  http-methods: ['GET']
  include-command-output-in-response: true
  include-command-output-in-response-on-error: true
  pass-arguments-to-command:
  - source: 'url'
    name: 'path'
  pass-environment-to-command:
  - source: 'string'
    envname: 'OUTPUT_FORMAT'
    name: 'json'
EOF
}
print_hardlink_yml() {
  cat <<EOF
- id: hardlink
  execute-command: '$WEBHOOK_BIN/hardlink.sh'
  command-working-directory: '$WORKDIR'
  http-methods: ['GET']
  include-command-output-in-response: true
  include-command-output-in-response-on-error: true
EOF
}
print_s3sync_yml() {
  cat <<EOF
- id: s3sync
  execute-command: '$WEBHOOK_BIN/s3sync.sh'
  command-working-directory: '$WORKDIR'
  http-methods: ['POST']
  include-command-output-in-response: true
  include-command-output-in-response-on-error: true
  pass-environment-to-command:
  - source: 'payload'
    envname: 'AWS_KEY'
    name: 'aws.key'
  - source: 'payload'
    envname: 'AWS_SECRET_KEY'
    name: 'aws.secret_key'
  - source: 'payload'
    envname: 'S3_BUCKET'
    name: 's3.bucket'
  - source: 'payload'
    envname: 'S3_REGION'
    name: 's3.region'
  - source: 'payload'
    envname: 'S3_PATH'
    name: 's3.path'
  - source: 'payload'
    envname: 'SCS_PATH'
    name: 'scs.path'
  stream-command-output: true
EOF
}
print_token_yml() {
  if [ "$1" ]; then
    cat << EOF
  trigger-rule:
    match:
      type: 'value'
      value: '$1'
      parameter:
        source: 'header'
        name: 'X-Webhook-Token'
EOF
  fi
}
exec_webhook() {
  # Validate WORKDIR
  if [ -z "$WEBHOOK_WORKDIR" ]; then
    echo "Must define the WEBHOOK_WORKDIR variable!" >&2
    exit 1
  fi
  WORKDIR="$(realpath "$WEBHOOK_WORKDIR" 2>/dev/null)" || true
  if [ ! -d "$WORKDIR" ]; then
    echo "The WEBHOOK_WORKDIR '$WEBHOOK_WORKDIR' is not a directory!" >&2
    exit 1
  fi
  # Get TOKENS, if the DU_TOKEN or HARDLINK_TOKEN is defined that is used, if
  # not if the COMMON_TOKEN that is used and in other case no token is checked
  # (that is the default)
  DU_TOKEN="${DU_TOKEN:-$COMMON_TOKEN}"
  HARDLINK_TOKEN="${HARDLINK_TOKEN:-$COMMON_TOKEN}"
  S3_TOKEN="${S3_TOKEN:-$COMMON_TOKEN}"
  # Create webhook configuration
  { 
    print_du_yml
    print_token_yml "$DU_TOKEN"
    echo ""
    print_hardlink_yml
    print_token_yml "$HARDLINK_TOKEN"
    echo ""
    print_s3sync_yml
    print_token_yml "$S3_TOKEN"
  }>"$WEBHOOK_YML"
  # Run the webhook command
  # shellcheck disable=SC2086
  exec webhook -hooks "$WEBHOOK_YML" $WEBHOOK_OPTS
}
# ----
# MAIN
# ----
case "$1" in
"server") exec_webhook ;;
*) exec "$@" ;;
esac

The entrypoint.sh script generates the configuration file for the webhook server calling functions that print a yaml section for each hook and optionally adds rules to validate access to them comparing the value of a X-Webhook-Token header against predefined values.

The expected token values are taken from environment variables, we can define a token variable for each hook (DU_TOKEN, HARDLINK_TOKEN or S3_TOKEN) and a fallback value (COMMON_TOKEN); if no token variable is defined for a hook no check is done and everybody can call it.

The Hook Definition documentation explains the options you can use for each hook, the ones we have right now do the following:

  • du: runs on the $WORKDIR directory, passes as first argument to the script the value of the path query parameter and sets the variable OUTPUT_FORMAT to the fixed value json (we use that to print the output of the script in JSON format instead of text).
  • hardlink: runs on the $WORKDIR directory and takes no parameters.
  • s3sync: runs on the $WORKDIR directory and sets a lot of environment variables from values read from the JSON encoded payload sent by the caller (all the values must be sent by the caller even if they are assigned an empty value, if they are missing the hook fails without calling the script); we also set the stream-command-output value to true to make the script show its output as it is working (we patched the webhook source to be able to use this option).

The du hook script

The du hook script code checks if the argument passed is a directory, computes its size using the du command and prints the results in text format or as a JSON dictionary:

hooks/du.sh 
#!/bin/sh
set -e
# Script to print disk usage for a PATH inside the scs folder
# ---------
# FUNCTIONS
# ---------
print_error() {
  if [ "$OUTPUT_FORMAT" = "json" ]; then
    echo "{\"error\":\"$*\"}"
  else
    echo "$*" >&2
  fi
  exit 1
}
usage() {
  if [ "$OUTPUT_FORMAT" = "json" ]; then
    echo "{\"error\":\"Pass arguments as '?path=XXX\"}"
  else
    echo "Usage: $(basename "$0") PATH" >&2
  fi
  exit 1
}
# ----
# MAIN
# ----
if [ "$#" -eq "0" ] || [ -z "$1" ]; then
  usage
fi
if [ "$1" = "." ]; then
  DU_PATH="./"
else
  DU_PATH="$(find . -name "$1" -mindepth 1 -maxdepth 1)" || true
fi
if [ -z "$DU_PATH" ] || [ ! -d "$DU_PATH/." ]; then
  print_error "The provided PATH ('$1') is not a directory"
fi
# Print disk usage in bytes for the given PATH
OUTPUT="$(du -b -s "$DU_PATH")"
if [ "$OUTPUT_FORMAT" = "json" ]; then
  # Format output as {"path":"PATH","bytes":"BYTES"}
  echo "$OUTPUT" |
    sed -e "s%^\(.*\)\t.*/\(.*\)$%{\"path\":\"\2\",\"bytes\":\"\1\"}%" |
    tr -d '\n'
else
  # Print du output as is
  echo "$OUTPUT"
fi
# vim: ts=2:sw=2:et:ai:sts=2

The hardlink hook script

The hardlink hook script is really simple, it just runs the util-linux version of the hardlink command on its working directory:

hooks/hardlink.sh 
#!/bin/sh
hardlink --ignore-time --maximize .

We use that to reduce the size of the stored content; to manage versions of files and folders we keep each version on a separate directory and when one or more files are not changed this script makes them hardlinks to the same file on disc, reducing the space used on disk.

The s3sync hook script

The s3sync hook script uses the s3fs tool to mount a bucket and synchronise data between a folder inside the bucket and a directory on the filesystem using rsync; all values needed to execute the task are taken from environment variables:

hooks/s3sync.sh 
#!/bin/ash
set -euo pipefail
set -o errexit
set -o errtrace
# Functions
finish() {
  ret="$1"
  echo ""
  echo "Script exit code: $ret"
  exit "$ret"
}
# Check variables
if [ -z "$AWS_KEY" ] || [ -z "$AWS_SECRET_KEY" ] || [ -z "$S3_BUCKET" ] ||
  [ -z "$S3_PATH" ] || [ -z "$SCS_PATH" ]; then
  [ "$AWS_KEY" ] || echo "Set the AWS_KEY environment variable"
  [ "$AWS_SECRET_KEY" ] || echo "Set the AWS_SECRET_KEY environment variable"
  [ "$S3_BUCKET" ] || echo "Set the S3_BUCKET environment variable"
  [ "$S3_PATH" ] || echo "Set the S3_PATH environment variable"
  [ "$SCS_PATH" ] || echo "Set the SCS_PATH environment variable"
  finish 1
fi
if [ "$S3_REGION" ] && [ "$S3_REGION" != "us-east-1" ]; then
  EP_URL="endpoint=$S3_REGION,url=https://s3.$S3_REGION.amazonaws.com"
else
  EP_URL="endpoint=us-east-1"
fi
# Prepare working directory
WORK_DIR="$(mktemp -p "$HOME" -d)"
MNT_POINT="$WORK_DIR/s3data"
PASSWD_S3FS="$WORK_DIR/.passwd-s3fs"
# Check the moutpoint
if [ ! -d "$MNT_POINT" ]; then
  mkdir -p "$MNT_POINT"
elif mountpoint "$MNT_POINT"; then
  echo "There is already something mounted on '$MNT_POINT', aborting!"
  finish 1
fi
# Create password file
touch "$PASSWD_S3FS"
chmod 0400 "$PASSWD_S3FS"
echo "$AWS_KEY:$AWS_SECRET_KEY" >"$PASSWD_S3FS"
# Mount s3 bucket as a filesystem
s3fs -o dbglevel=info,retries=5 -o "$EP_URL" -o "passwd_file=$PASSWD_S3FS" \
  "$S3_BUCKET" "$MNT_POINT"
echo "Mounted bucket '$S3_BUCKET' on '$MNT_POINT'"
# Remove the password file, just in case
rm -f "$PASSWD_S3FS"
# Check source PATH
ret="0"
SRC_PATH="$MNT_POINT/$S3_PATH"
if [ ! -d "$SRC_PATH" ]; then
  echo "The S3_PATH '$S3_PATH' can't be found!"
  ret=1
fi
# Compute SCS_UID & SCS_GID (by default based on the working directory owner)
SCS_UID="${SCS_UID:=$(stat -c "%u" "." 2>/dev/null)}" || true
SCS_GID="${SCS_GID:=$(stat -c "%g" "." 2>/dev/null)}" || true
# Check destination PATH
DST_PATH="./$SCS_PATH"
if [ "$ret" -eq "0" ] && [ -d "$DST_PATH" ]; then
  mkdir -p "$DST_PATH" || ret="$?"
fi
# Copy using rsync
if [ "$ret" -eq "0" ]; then
  rsync -rlptv --chown="$SCS_UID:$SCS_GID" --delete --stats \
    "$SRC_PATH/" "$DST_PATH/" || ret="$?"
fi
# Unmount the S3 bucket
umount -f "$MNT_POINT"
echo "Called umount for '$MNT_POINT'"
# Remove mount point dir
rmdir "$MNT_POINT"
# Remove WORK_DIR
rmdir "$WORK_DIR"
# We are done
finish "$ret"
# vim: ts=2:sw=2:et:ai:sts=2

Deployment objects

The system is deployed as a StatefulSet with one replica.

Our production deployment is done on AWS and to be able to scale we use EFS for our PersistenVolume; the idea is that the volume has no size limit, its AccessMode can be set to ReadWriteMany and we can mount it from multiple instances of the Pod without issues, even if they are in different availability zones.

For development we use k3d and we are also able to scale the StatefulSet for testing because we use a ReadWriteOnce PVC, but it points to a hostPath that is backed up by a folder that is mounted on all the compute nodes, so in reality Pods in different k3d nodes use the same folder on the host.

secrets.yaml

The secrets file contains the files used by the mysecureshell container that can be generated using kubernetes pods as follows (we are only creating the scs user):

$ kubectl run "mysecureshell" --restart='Never' --quiet --rm --stdin \
  --image "stodh/mysecureshell:latest" -- gen-host-keys >"./host_keys.txt"
$ kubectl run "mysecureshell" --restart='Never' --quiet --rm --stdin \
  --image "stodh/mysecureshell:latest" -- gen-users-tar scs >"./users.tar"

Once we have the files we can generate the secrets.yaml file as follows:

$ tar xf ./users.tar user_keys.txt user_pass.txt
$ kubectl --dry-run=client -o yaml create secret generic "scs-secret" \
  --from-file="host_keys.txt=host_keys.txt" \
  --from-file="user_keys.txt=user_keys.txt" \
  --from-file="user_pass.txt=user_pass.txt" > ./secrets.yaml

The resulting secrets.yaml will look like the following file (the base64 would match the content of the files, of course):

secrets.yaml 
apiVersion: v1
data:
  host_keys.txt: TWlt...
  user_keys.txt: c2Nz...
  user_pass.txt: c2Nz...
kind: Secret
metadata:
  creationTimestamp: null
  name: scs-secret

pvc.yaml

The persistent volume claim for a simple deployment (one with only one instance of the statefulSet) can be as simple as this:

pvc.yaml 
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: scs-pvc
  labels:
    app.kubernetes.io/name: scs
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 8Gi

On this definition we don’t set the storageClassName to use the default one.

Volumes in our development environment (k3d)

In our development deployment we create the following PersistentVolume as required by the Local Persistence Volume Static Provisioner (note that the /volumes/scs-pv has to be created by hand, in our k3d system we mount the same host directory on the /volumes path of all the nodes and create the scs-pv directory by hand before deploying the persistent volume):

k3d-pv.yaml 
apiVersion: v1
kind: PersistentVolume
metadata:
  name: scs-pv
  labels:
    app.kubernetes.io/name: scs
spec:
  capacity:
    storage: 8Gi
  volumeMode: Filesystem
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Delete
  claimRef:
    name: scs-pvc
  storageClassName: local-storage
  local:
    path: /volumes/scs-pv
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: node.kubernetes.io/instance-type
          operator: In
          values:
          - k3s

And to make sure that everything works as expected we update the PVC definition to add the right storageClassName:

k3d-pvc.yaml 
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: scs-pvc
  labels:
    app.kubernetes.io/name: scs
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 8Gi
  storageClassName: local-storage

Volumes in our production environment (aws)

In the production deployment we don’t create the PersistentVolume (we are using the aws-efs-csi-driver which supports Dynamic Provisioning) but we add the storageClassName (we set it to the one mapped to the EFS driver, i.e. efs-sc) and set ReadWriteMany as the accessMode:

efs-pvc.yaml 
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: scs-pvc
  labels:
    app.kubernetes.io/name: scs
spec:
  accessModes:
  - ReadWriteMany
  resources:
    requests:
      storage: 8Gi
  storageClassName: efs-sc

statefulset.yaml

The definition of the statefulSet is as follows:

statefulset.yaml 
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: scs
  labels:
    app.kubernetes.io/name: scs
spec:
  serviceName: scs
  replicas: 1
  selector:
    matchLabels:
      app: scs
  template:
    metadata:
      labels:
        app: scs
    spec:
      containers:
      - name: nginx
        image: stodh/nginx-scs:latest
        ports:
        - containerPort: 80
          name: http
        env:
        - name: AUTH_REQUEST_URI
          value: ""
        - name: HTML_ROOT
          value: /sftp/data
        volumeMounts:
        - mountPath: /sftp
          name: scs-datadir
      - name: mysecureshell
        image: stodh/mysecureshell:latest
        ports:
        - containerPort: 22
          name: ssh
        securityContext:
          capabilities:
            add:
            - IPC_OWNER
        env:
        - name: SFTP_UID
          value: '2020'
        - name: SFTP_GID
          value: '2020'
        volumeMounts:
        - mountPath: /secrets
          name: scs-file-secrets
          readOnly: true
        - mountPath: /sftp
          name: scs-datadir
      - name: webhook
        image: stodh/webhook-scs:latest
        securityContext:
          privileged: true
        ports:
        - containerPort: 9000
          name: webhook-http
        env:
        - name: WEBHOOK_WORKDIR
          value: /sftp/data/scs
        volumeMounts:
        - name: devfuse
          mountPath: /dev/fuse
        - mountPath: /sftp
          name: scs-datadir
      volumes:
      - name: devfuse
        hostPath:
          path: /dev/fuse
      - name: scs-file-secrets
        secret:
          secretName: scs-secrets
      - name: scs-datadir
        persistentVolumeClaim:
          claimName: scs-pvc

Notes about the containers:

  • nginx: As this is an example the web server is not using an AUTH_REQUEST_URI and uses the /sftp/data directory as the root of the web (to get to the files uploaded for the scs user we will need to use /scs/ as a prefix on the URLs).
  • mysecureshell: We are adding the IPC_OWNER capability to the container to be able to use some of the sftp-* commands inside it, but they are not really needed, so adding the capability is optional.
  • webhook: We are launching this container in privileged mode to be able to use the s3fs-fuse, as it will not work otherwise for now (see this kubernetes issue); if the functionality is not needed the container can be executed with regular privileges; besides, as we are not enabling public access to this service we don’t define *_TOKEN variables (if required the values should be read from a Secret object).

Notes about the volumes:

  • the devfuse volume is only needed if we plan to use the s3fs command on the webhook container, if not we can remove the volume definition and its mounts.

service.yaml

To be able to access the different services on the statefulset we publish the relevant ports using the following Service object:

service.yaml 
apiVersion: v1
kind: Service
metadata:
  name: scs-svc
  labels:
    app.kubernetes.io/name: scs
spec:
  ports:
  - name: ssh
    port: 22
    protocol: TCP
    targetPort: 22
  - name: http
    port: 80
    protocol: TCP
    targetPort: 80
  - name: webhook-http
    port: 9000
    protocol: TCP
    targetPort: 9000
  selector:
    app: scs

ingress.yaml

To download the scs files from the outside we can add an ingress object like the following (the definition is for testing using the localhost name):

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: scs-ingress
  labels:
    app.kubernetes.io/name: scs
spec:
  ingressClassName: nginx
  rules:
  - host: 'localhost'
    http:
      paths:
      - path: /scs
        pathType: Prefix
        backend:
          service:
            name: scs-svc
            port:
              number: 80

Deployment

To deploy the statefulSet we create a namespace and apply the object definitions shown before:

$ kubectl create namespace scs-demo
namespace/scs-demo created
$ kubectl -n scs-demo apply -f secrets.yaml
secret/scs-secrets created
$ kubectl -n scs-demo apply -f pvc.yaml
persistentvolumeclaim/scs-pvc created
$ kubectl -n scs-demo apply -f statefulset.yaml
statefulset.apps/scs created
$ kubectl -n scs-demo apply -f service.yaml
service/scs-svc created
$ kubectl -n scs-demo apply -f ingress.yaml
ingress.networking.k8s.io/scs-ingress created

Once the objects are deployed we can check that all is working using kubectl:

$ kubectl  -n scs-demo get all,secrets,ingress
NAME        READY   STATUS    RESTARTS   AGE
pod/scs-0   3/3     Running   0          24s

NAME            TYPE       CLUSTER-IP  EXTERNAL-IP  PORT(S)                  AGE
service/scs-svc ClusterIP  10.43.0.47  <none>       22/TCP,80/TCP,9000/TCP   21s

NAME                   READY   AGE
statefulset.apps/scs   1/1     24s

NAME                         TYPE                                  DATA   AGE
secret/default-token-mwcd7   kubernetes.io/service-account-token   3      53s
secret/scs-secrets           Opaque                                3      39s

NAME                                   CLASS  HOSTS      ADDRESS     PORTS   AGE
ingress.networking.k8s.io/scs-ingress  nginx  localhost  172.21.0.5  80      17s

At this point we are ready to use the system.

Usage examples

File uploads

As previously mentioned in our system the idea is to use the sftp server from other Pods, but to test the system we are going to do a kubectl port-forward and connect to the server using our host client and the password we have generated (it is on the user_pass.txt file, inside the users.tar archive):

$ kubectl -n scs-demo port-forward service/scs-svc 2020:22 &
Forwarding from 127.0.0.1:2020 -> 22
Forwarding from [::1]:2020 -> 22
$ PF_PID=$!
$ sftp -P 2020 scs@127.0.0.1                                                 1
Handling connection for 2020
The authenticity of host '[127.0.0.1]:2020 ([127.0.0.1]:2020)' can't be \
  established.
ED25519 key fingerprint is SHA256:eHNwCnyLcSSuVXXiLKeGraw0FT/4Bb/yjfqTstt+088.
This key is not known by any other names
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '[127.0.0.1]:2020' (ED25519) to the list of known \
  hosts.
scs@127.0.0.1's password: **********
Connected to 127.0.0.1.
sftp> ls -la
drwxr-xr-x    2 sftp     sftp         4096 Sep 25 14:47 .
dr-xr-xr-x    3 sftp     sftp         4096 Sep 25 14:36 ..
sftp> !date -R > /tmp/date.txt                                               2
sftp> put /tmp/date.txt .
Uploading /tmp/date.txt to /date.txt
date.txt                                      100%   32    27.8KB/s   00:00
sftp> ls -l
-rw-r--r--    1 sftp     sftp           32 Sep 25 15:21 date.txt
sftp> ln date.txt date.txt.1                                                 3
sftp> ls -l
-rw-r--r--    2 sftp     sftp           32 Sep 25 15:21 date.txt
-rw-r--r--    2 sftp     sftp           32 Sep 25 15:21 date.txt.1
sftp> put /tmp/date.txt date.txt.2                                           4
Uploading /tmp/date.txt to /date.txt.2
date.txt                                      100%   32    27.8KB/s   00:00
sftp> ls -l                                                                  5
-rw-r--r--    2 sftp     sftp           32 Sep 25 15:21 date.txt
-rw-r--r--    2 sftp     sftp           32 Sep 25 15:21 date.txt.1
-rw-r--r--    1 sftp     sftp           32 Sep 25 15:21 date.txt.2
sftp> exit
$ kill "$PF_PID"
[1]  + terminated  kubectl -n scs-demo port-forward service/scs-svc 2020:22
  1. We connect to the sftp service on the forwarded port with the scs user.
  2. We put a file we have created on the host on the directory.
  3. We do a hard link of the uploaded file.
  4. We put a second copy of the file we created locally.
  5. On the file list we can see that the two first files have two hardlinks

File retrievals

If our ingress is configured right we can download the date.txt file from the URL http://localhost/scs/date.txt:

$ curl -s http://localhost/scs/date.txt
Sun, 25 Sep 2022 17:21:51 +0200

Use of the webhook container

To finish this post we are going to show how we can call the hooks directly, from a CronJob and from a Job.

Direct script call (du)

In our deployment the direct calls are done from other Pods, to simulate it we are going to do a port-forward and call the script with an existing PATH (the root directory) and a bad one:

$ kubectl -n scs-demo port-forward service/scs-svc 9000:9000 >/dev/null &
$ PF_PID=$!
$ JSON="$(curl -s "http://localhost:9000/hooks/du?path=.")"
$ echo $JSON
{"path":"","bytes":"4160"}
$ JSON="$(curl -s "http://localhost:9000/hooks/du?path=foo")"
$ echo $JSON
{"error":"The provided PATH ('foo') is not a directory"}
$ kill $PF_PID

As we only have files on the base directory we print the disk usage of the . PATH and the output is in json format because we export OUTPUT_FORMAT with the value json on the webhook configuration.

Cronjobs (hardlink)

As explained before, the webhook container can be used to run cronjobs; the following one uses an alpine container to call the hardlink script each minute (that setup is for testing, obviously):

webhook-cronjob.yaml 
apiVersion: batch/v1
kind: CronJob
metadata:
  name: hardlink
  labels:
    cronjob: 'hardlink'
spec:
  schedule: "* */1 * * *"
  concurrencyPolicy: Replace
  jobTemplate:
    spec:
      template:
        metadata:
          labels:
            cronjob: 'hardlink'
        spec:
          containers:
          - name: hardlink-cronjob
            image: alpine:latest
            command: ["wget", "-q", "-O-", "http://scs-svc:9000/hooks/hardlink"]
          restartPolicy: Never

The following console session shows how we create the object, allow a couple of executions and remove it (in production we keep it running but once a day, not each minute):

$ kubectl -n scs-demo apply -f webhook-cronjob.yaml                          1
cronjob.batch/hardlink created
$ kubectl -n scs-demo get pods -l "cronjob=hardlink" -w                      2
NAME                      READY   STATUS    RESTARTS   AGE
hardlink-27735351-zvpnb   0/1     Pending   0          0s
hardlink-27735351-zvpnb   0/1     ContainerCreating   0          0s
hardlink-27735351-zvpnb   0/1     Completed           0          2s
^C
$ kubectl -n scs-demo logs pod/hardlink-27735351-zvpnb                       3
Mode:                     real
Method:                   sha256
Files:                    3
Linked:                   1 files
Compared:                 0 xattrs
Compared:                 1 files
Saved:                    32 B
Duration:                 0.000220 seconds
$ sleep 60
$ kubectl -n scs-demo get pods -l "cronjob=hardlink"                         4
NAME                      READY   STATUS      RESTARTS   AGE
hardlink-27735351-zvpnb   0/1     Completed   0          83s
hardlink-27735352-br5rn   0/1     Completed   0          23s
$ kubectl -n scs-demo logs pod/hardlink-27735352-br5rn                       5
Mode:                     real
Method:                   sha256
Files:                    3
Linked:                   0 files
Compared:                 0 xattrs
Compared:                 0 files
Saved:                    0 B
Duration:                 0.000070 seconds
$ kubectl -n scs-demo delete -f webhook-cronjob.yaml                         6
cronjob.batch "hardlink" deleted
  1. This command creates the cronjob object.
  2. This checks the pods with our cronjob label, we interrupt it once we see that the first run has been completed.
  3. With this command we see the output of the execution, as this is the fist execution we see that date.txt.2 has been replaced by a hardlink (the summary does not name the file, but it is the only option knowing the contents from the original upload).
  4. After waiting a little bit we check the pods executed again to get the name of the latest one.
  5. The log now shows that nothing was done.
  6. As this is a demo, we delete the cronjob.

Jobs (s3sync)

The following job can be used to synchronise the contents of a directory in a S3 bucket with the SCS Filesystem:

job.yaml 
apiVersion: batch/v1
kind: Job
metadata:
  name: s3sync
  labels:
    cronjob: 's3sync'
spec:
  template:
    metadata:
      labels:
        cronjob: 's3sync'
    spec:
      containers:
      - name: s3sync-job
        image: alpine:latest
        command: 
        - "wget"
        - "-q"
        - "--header"
        - "Content-Type: application/json"
        - "--post-file"
        - "/secrets/s3sync.json"
        - "-O-"
        - "http://scs-svc:9000/hooks/s3sync"
        volumeMounts:
        - mountPath: /secrets
          name: job-secrets
          readOnly: true
      restartPolicy: Never
      volumes:
      - name: job-secrets
        secret:
          secretName: webhook-job-secrets

The file with parameters for the script must be something like this:

s3sync.json 
{
  "aws": {
    "key": "********************",
    "secret_key": "****************************************"
  },
  "s3": {
    "region": "eu-north-1",
    "bucket": "blogops-test",
    "path": "test"
  },
  "scs": {
    "path": "test"
  }
}

Once we have both files we can run the Job as follows:

$ kubectl -n scs-demo create secret generic webhook-job-secrets \            1
  --from-file="s3sync.json=s3sync.json"
secret/webhook-job-secrets created
$ kubectl -n scs-demo apply -f webhook-job.yaml                              2
job.batch/s3sync created
$ kubectl -n scs-demo get pods -l "cronjob=s3sync"                           3
NAME           READY   STATUS      RESTARTS   AGE
s3sync-zx2cj   0/1     Completed   0          12s
$ kubectl -n scs-demo logs s3sync-zx2cj                                      4
Mounted bucket 's3fs-test' on '/root/tmp.jiOjaF/s3data'
sending incremental file list
created directory ./test
./
kyso.png

Number of files: 2 (reg: 1, dir: 1)
Number of created files: 2 (reg: 1, dir: 1)
Number of deleted files: 0
Number of regular files transferred: 1
Total file size: 15,075 bytes
Total transferred file size: 15,075 bytes
Literal data: 15,075 bytes
Matched data: 0 bytes
File list size: 0
File list generation time: 0.147 seconds
File list transfer time: 0.000 seconds
Total bytes sent: 15,183
Total bytes received: 74

sent 15,183 bytes  received 74 bytes  30,514.00 bytes/sec
total size is 15,075  speedup is 0.99
Called umount for '/root/tmp.jiOjaF/s3data'

Script exit code: 0
$ kubectl -n scs-demo delete -f webhook-job.yaml                             5
job.batch "s3sync" deleted
$ kubectl -n scs-demo delete secrets webhook-job-secrets                     6
secret "webhook-job-secrets" deleted
  1. Here we create the webhook-job-secrets secret that contains the s3sync.json file.
  2. This command runs the job.
  3. Checking the label cronjob=s3sync we get the Pods executed by the job.
  4. Here we print the logs of the completed job.
  5. Once we are finished we remove the Job.
  6. And also the secret.

Final remarks

This post has been longer than I expected, but I believe it can be useful for someone; in any case, next time I’ll try to explain something shorter or will split it into multiple entries.

25 September, 2022 10:12PM

hackergotchi for Shirish Agarwal

Shirish Agarwal

Rama II, Arthur C. Clarke, Aliens

Rama II

This would be more of a short post about the current book I am reading. Now people who have seen Arrival would probably be more at home. People who have also seen Avatar would also be familiar to the theme or concept I am sharing about. Now before I go into detail, it seems that Arthur C. Clarke wanted to use a powerful god or mythological character for the name and that is somehow the RAMA series started.

Now the first book in the series explores an extraterrestrial spaceship that earth people see/connect with. The spaceship is going somewhere and is doing an Earth flyby so humans don’t have much time to explore the spaceship and it is difficult to figure out how the spaceship worked. The spaceship is around 40 km. long. They don’t meet any living Ramans but mostly automated systems and something called biots.

As I’m still reading it, I can’t really say what happens next. Although in Rama or Rama I, the powers that be want to destroy it while in the end last they don’t. Whether they could have destroyed it or not would be whole another argument. What people need to realize is that the book is a giant ‘What IF’ scenario.

Aliens

If there were any intelligent life in the Universe, I don’t think they will take the pain of visiting Earth. And the reasons are far more mundane than anything else. Look at how we treat each other. One of the largest democracies on Earth, The U.S. has been so divided. While the progressives have made some good policies, the Republicans are into political stunts, consider the political stunt of sending Refugees to Martha’s Vineyard. The ex-president also made a statement that he can declassify anything just by thinking about it. Now understand this, a refugee is a legal migrant whose papers would be looked into by the American Govt. and till the time he/she/their application is approved or declined they can work, have a house, or do whatever to support themselves. There is a huge difference between having refugee status and being an undocumented migrant. And it isn’t as if the Republicans don’t know this, they did it because they thought they will be able to get away with it.

Both the above episodes don’t throw us in a good light. If we treat others like the above, how can we expect to be treated? And refugees always have a hard time, not just in the U.S, , the UK you name it. The UK just some months ago announced a controversial deal where they will send Refugees to Rwanda while their refugee application is accepted or denied, most of them would be denied.

The Indian Government is more of the same. A friend, a casual acquaintance Nishant Shah shared the same issues as I had shared a few weeks back even though he’s an NRI. So, it seems we are incapable of helping ourselves as well as helping others. On top of it, we have the temerity of using the word ‘alien’ for them.

Now, just for a moment, imagine you are an intelligent life form. An intelligent life-form that could coax energy from the stars, why would you come to Earth, where the people at large have already destroyed more than half of the atmosphere and still arguing about it with the other half. On top of it, we see a list of authoritarian figures like Putin, Xi Jinping whose whole idea is to hold on to power for as long as they can, damn the consequences. Mr. Modi is no different, he is the dumbest of the lot and that’s saying something. Most of the projects made by him are in disarray, Pune Metro, my city giving an example. And this is when Pune was the first applicant to apply for a Metro. Just like the UK, India too has tanked the economy under his guidance. Every time they come closer to target dates, the targets are put far into the future, for e.g. now they have said 2040 for a good economy. And just like in other countries, he has some following even though he has a record of failure in every sector of the economy, education, and defense, the list is endless. There isn’t a single accomplishment by him other than screwing with other religions. Most of my countrymen also don’t really care or have a bother to see how the economy grows and how exports play a crucial part otherwise they would be more alert. Also, just like the UK, India too gave tax cuts to the wealthy, most people don’t understand how economies function and the PM doesn’t care. The media too is subservient and because nobody asks the questions, nobody seems to be accountable :(.

Religion

There is another aspect that also has been to the fore, just like in medieval times, I see a great fervor for religion happening here, especially since the pandemic and people are much more insecure than ever before. Before, I used to think that insecurity and religious appeal only happen in the uneducated, and I was wrong. I have friends who are highly educated and yet still are blinded by religion. In many such cases or situations, I find their faith to be a sham. If you have faith, then there shouldn’t be any room for doubt or insecurity. And if you are not in doubt or insecure, you won’t need to talk about your religion. The difference between the two is that a person is satiated himself/herself/themselves with thirst and hunger. That person would be in a relaxed mode while the other person would continue to create drama as there is no peace in their heart.

Another fact is none of the major religions, whether it is Christianity, Islam, Buddhism or even Hinduism has allowed for the existence of extraterrestrials. We have already labeled them as ‘aliens’ even before meeting them & just our imagination. And more often than not, we end up killing them. There are and have been scores of movies that have explored the idea. Independence day, Aliens, Arrival, the list goes on and on. And because our religions have never thought about the idea of ET’s and how they will affect us, if ET’s do come, all the religions and religious practices would panic and die. That is the possibility why even the 1947 Roswell Incident has been covered up .

If the above was not enough, the bombing of Hiroshima and Nagasaki by the Americans would always be a black mark against humanity. From the alien perspective, if you look at the technology that they have vis-a-vis what we have, they will probably think of us as spoilt babies and they wouldn’t be wrong. Spoilt babies with nuclear weapons are not exactly a healthy mix 😦

Earth

To add to our fragile ego, we didn’t even leave earth even though we have made sure we exploit it as much as we can. We even made the anthropocentric or homocentric view that makes man the apex animal and to top it we have this weird idea that extraterrestrials come here or will invade for water. A species that knows how to get energy out of stars but cannot make a little of H2O. The idea belies logic and again has been done to death. Why we as humans are so insecure even though we have been given so much I fail to understand. I have shared on numerous times the Kardeshev Scale on this blog itself.

The above are some of the reasons why Arthur C. Clarke’s works are so controversial and this is when I haven’t even read the whole book. It forces us to ask questions that we normally would never think about. And I have to repeat that when these books were published for the first time, they were new ideas. All the movies, from Stanley Kubrick’s 2001: Space Odyssey, Aliens, Arrival, and Avatar, somewhere or the other reference some aspect of this work. It is highly possible that I may read and re-read the book couple of times before beginning the next one. There is also quite a bit of human drama, but then that is to be expected. I have to admit I did have some nice dreams after reading just the first few pages, imagining being given the opportunity to experience an Extraterrestrial spaceship that is beyond our wildest dreams. While the Governments may try to cover up or something, the ones who get to experience that spacecraft would be unimaginable. And if they were able to share the pictures or a Livestream, it would be nothing short of amazing.

For those who want to, there is a lot going on with the New James Webb Telescope. I am sure it would give rise to more questions than answers.

25 September, 2022 09:07AM by shirishag75

September 24, 2022

Ian Jackson

Please vote in favour of the Debian Social Contract change

tl;dr: Please vote in favour of the Debian Social Contract change, by ranking all of its options above None of the Above. Rank the SC change options above corresponding options that do not change the Social Contract.

Vote to change the SC even if you think the change is not necessary for Debian to prominently/officially provide an installer with-nonfree-firmware.

Why vote for SC change even if I think it’s not needed?

I’m addressing myself primarily to the reader who agrees with me that Debian ought to be officially providing with-firmware images. I think it is very likely that the winning option will be one of the ones which asks for an official and prominent with-firmware installer.

However, many who oppose this change believe that it would be a breach of Debian’s Social Contract. This is a very reasonable and arguable point of view. Indeed, I’m inclined to share it.

If the winning option is to provide a with-firmware installer (perhaps, only a with-firmware installer) those people will feel aggrieved. They will, quite reasonably, claim that the result of the vote is illegitimate - being contrary to Debian’s principles as set out in the Social Contract, which require a 3:1 majority to change.

There is even the possibility that the Secretary may declare the GR result void, as contrary to the Constitution! (Sadly, I am not making this up.) This would cast Debian into (yet another) acrimonious constitutional and governance crisis.

The simplest answer is to amend the Social Contract to explicitly permit what is being proposed. Holger’s option F and Russ’s option E do precisely that.

Amending the SC is not an admission that it was legally necessary to do so. It is practical politics: it ensures that we have clear authority and legitimacy.

Aren’t we softening Debian’s principles?

I think prominently distributing an installer that can work out of the box on the vast majority of modern computers would help Debian advance our users’ freedom.

I see user freedom as a matter of practical capability, not theoretical purity. Anyone living in the modern world must make compromises. It is Debian’s job to help our users (and downstreams) minimise those compromises and retain as much control as possible over the computers in their life. Insisting that a user buys different hardware, or forcing them to a different distro, does not serve that goal.

I don’t really expect to convince anyone with such a short argument, but I do want to make the point that providing an installer that users can use to obtain a lot of practical freedom is also, for many of us, a matter of principle.



comment count unavailable comments

24 September, 2022 07:08PM

September 23, 2022

hackergotchi for Gunnar Wolf

Gunnar Wolf

6237415

Years ago, it was customary that some of us stated publicly the way we think in time of Debian General Resolutions (GRs). And even if we didn’t, vote lists were open (except when voting for people, i.e. when electing a DPL), so if interested we could understand what our different peers thought.

This is the first vote, though, where a Debian vote is protected under voting secrecy. I think it is sad we chose that path, as I liken a GR vote more with a voting process within a general assembly of a cooperative than with a countrywide voting one; I feel that understanding who is behind each posture helps us better understand the project as a whole.

But anyway, I’m digressing… Even though I remained quiet during much of the discussion period (I was preparing and attending a conference), I am very much interested in this vote — I am the maintainer for the Raspberry Pi firmware, and am a seconder for two of them. Many people know me for being quite inflexible in my interpretation of what should be considered Free Software, and I’m proud of it. But still, I believer it to be fundamental for Debian to be able to run on the hardware most users have.

So… My vote was as follows:

[6] Choice 1: Only one installer, including non-free firmware
[2] Choice 2: Recommend installer containing non-free firmware
[3] Choice 3: Allow presenting non-free installers alongside the free one
[7] Choice 4: Installer with non-free software is not part of Debian
[4] Choice 5: Change SC for non-free firmware in installer, one installer
[1] Choice 6: Change SC for non-free firmware in installer, keep both installers
[5] Choice 7: None Of The Above

For people reading this not into Debian’s voting processes: Debian uses the cloneproof Schwatz sequential dropping Condorcet method, which means we don’t only choose our favorite option (which could lead to suboptimal strategic voting outcomes), but we rank all the options according to our preferences.

To read this vote, we should first locate position of “None of the above”, which for my ballot is #5. Let me reorder the ballot according to my preferences:

[1] Choice 6: Change SC for non-free firmware in installer, keep both installers
[2] Choice 2: Recommend installer containing non-free firmware
[3] Choice 3: Allow presenting non-free installers alongside the free one
[4] Choice 5: Change SC for non-free firmware in installer, one installer
[5] Choice 7: None Of The Above
[6] Choice 1: Only one installer, including non-free firmware
[7] Choice 4: Installer with non-free software is not part of Debian

This is, I don’t agree either with Steve McIntyre’s original proposal, Choice 1 (even though I seconded it, this means, I think it’s very important to have this vote, and as a first proposal, it’s better than the status quo — maybe it’s contradictory that I prefer it to the status quo, but ranked it below NotA. Well, more on that when I present Choice 5).

My least favorite option is Choice 4, presented by Simon Josefsson, which represents the status quo: I don’t want Debian not to have at all an installer that cannot be run on most modern hardware with reasonably good user experience (i.e. network support — or the ability to boot at all!)

Slightly above my acceptability threshold, I ranked Choice 5, presented by Russ Allbery. Debian’s voting and its constitution rub each other in interesting ways, so the Project Secretary has to run the votes as they are presented… but he has interpreted Choice 1 to be incompatible with the Social Contract (as there would no longer be a DFSG-free installer available), and if it wins, it could lead him to having to declare the vote invalid. I don’t want that to happen, and that’s why I ranked Choice 1 below None of the above.

[update/note] Several people have asked me to back that the Secretary said so. I can refer to four mails: 2022.08.29, 2022.08.30, 2022.09.02, 2022.09.04.

Other than that, Choice 6 (proposed by Holger Levsen), Choice 2 (proposed by me) and Choice 3 (proposed by Bart Martens) are very much similar; the main difference is that Choice 6 includes a modification to the Social Contract expressing that:

The Debian official media may include firmware that is otherwise not
part of the Debian system to enable use of Debian with hardware that
requires such firmware.

I believe choices 2 and 3 to be mostly the same, being Choice 2 more verbose in explaining the reasoning than Choice 3.

Oh! And there are always some more bits to the discussion… For example, given they hold modifications to the Social Contract, both Choice 5 and Choice 6 need a 3:1 supermajority to be valid.

So, lets wait until the beginning of October to get the results, and to implement the changes they will (or not?) allow. If you are a Debian Project Member, please vote!

23 September, 2022 04:03PM

hackergotchi for Steve Kemp

Steve Kemp

Lisp macros are magical

In my previous post I introduced yet another Lisp interpreter. When it was posted there was no support for macros.

Since I've recently returned from a visit to the UK, and caught COVID-19 while I was there, I figured I'd see if my brain was fried by adding macro support.

I know lisp macros are awesome, it's one of those things that everybody is told. Repeatedly. I've used macros in my emacs programming off and on for a good few years, but despite that I'd not really given them too much thought.

If you know anything about lisp you know that it's all about the lists, the parenthesis, and the macros. Here's a simple macro I wrote:

 (define if2 (macro (pred one two)
    `(if ~pred (begin ~one ~two))))

The standard lisp if function allows you to write:

 (if (= 1 a) (print "a == 1") (print "a != 1"))

There are three arguments supplied to the if form:

  • The test to perform.
  • A single statement to execute if the test was true.
  • A single statement to execute if the test was not true.

My if2 macro instead has three arguments:

  • The test to perform.
  • The first statement to execute if the test was true.
  • The second statement to execute if the test was true.
  • i.e. There is no "else", or failure, clause.

This means I can write:

 (if2 blah
    (one..)
    (two..))

Rather than:

 (if blah
    (begin
       (one..)
       (two..)))

It is simple, clear, and easy to understand and a good building-block for writing a while function:

 (define while-fun (lambda (predicate body)
    (if2 (predicate)
       (body)
       (while-fun predicate body))))

There you see that if the condition is true then we call the supplied body, and then recurse. Doing two actions as a result of the single if test is a neat shortcut.

Of course we need to wrap that up in a macro, for neatness:

(define while (macro (expression body)
                 (list 'while-fun
                       (list 'lambda '() expression)
                       (list 'lambda '() body))))

Now we're done, and we can run a loop five times like so:

(let ((a 5))
  (while (> a 0)
     (begin
        (print "(while) loop - iteration %s" a)
        (set! a (- a 1) true))))

Output:

(while) loop - iteration 5
(while) loop - iteration 4
(while) loop - iteration 3
(while) loop - iteration 2
(while) loop - iteration 1

We've gone from using lists to having a while-loop, with a couple of simple macros and one neat recursive function.

There are a lot of cute things you can do with macros, and now I'm starting to appreciate them a little more. Of course it's not quite as magical as FORTH, but damn close!

23 September, 2022 02:30PM

Reproducible Builds (diffoscope)

diffoscope 222 released

The diffoscope maintainers are pleased to announce the release of diffoscope version 222. This version includes the following changes:

[ Mattia Rizzolo ]
* Use pep517 and pip to load the requirements. (Closes: #1020091)
* Remove old Breaks/Replaces in debian/control that have been obsoleted since
  bullseye

You find out more by visiting the project homepage.

23 September, 2022 12:00AM

September 22, 2022

hackergotchi for Jonathan Dowland

Jonathan Dowland

Nine Inch Nails, Cornwall, June

In June I travelled to see Nine Inch Nails perform two nights at the Eden Project in Cornwall. It'd been eight years since I last saw them live and when they announced the Eden shows, I thought it might be the only chance I'd get to see them for a long time. I committed, and sods law, a week or so later they announced a handful of single-night UK club shows. On the other hand, on previous tours where they'd typically book two club nights in each city, I've attended one night and always felt I should have done both, so this time I was making that happen.

Newquay

approach by air

approach by air

Towan Beach (I think)

Towan Beach (I think)

For personal reasons it's been a difficult year so it was nice to treat myself to a mini holiday. I stayed in Newquay, a seaside town with many similarities to the North East coast, as well as many differences. It's much bigger, and although we have a thriving surfing community in Tynemouth, Newquay have it on another level. They also have a lot more tourism, which is a double-edged sword: in Newquay, besides surfing, there was not a lot to do. There's a lot of tourist tat shops, and bars and cafes (som very nice ones), but no book shops, no record shops, very few of the quaint, unique boutique places we enjoy up here and possibly take for granted.

If you want tie-dyed t-shirts though, you're sorted.

Nine Inch Nails have a long-established, independently fan-run forum called Echoing The Sound. There is now also an official Discord server. I asked on both whether anyone was around in Newquay and wanted to meet up: not many people were! But I did meet a new friend, James, for a quiet drink. He was due to share a taxi with Sarah, who was flying in but her flight was delayed and she had to figure out another route.

Eden Project

the Eden Project

the Eden Project

The Eden Project, the venue itself, is a fascinating place. I didn't realise until I'd planned most of my time there that the gig tickets granted you free entry into the Project on the day of the gig as well as the day after. It was quite tricky to get from Newquay to the Eden project, I would have been better off staying in St Austell itself perhaps, so I didn't take advantage of this, but I did have a couple of hours total to explore a little bit at the venue before the gig on each night.

Friday 17th (sunny)

Once I got to the venue I managed to meet up with several names from ETS and the Discord: James, Sarah (who managed to re-arrange flights), Pete and his wife (sorry I missed your name), Via Tenebrosa (she of crab hat fame), Dave (DaveDiablo), Elliot and his sister and finally James (sheapdean), someone who I've been talking to online for over a decade and finally met in person (and who taped both shows). I also tried to meet up with a friend from the Debian UK community (hi Lief) but I couldn't find him!

Support for Friday was Nitzer Ebb, who I wasn't familiar with before. There were two men on stage, one operating instruments, the other singing. It was a tough time to warm up the crowd, the venue was still very empty and it was very bright and sunny, but I enjoyed what I was hearing. They're definitely on my list. I later learned that the band's regular singer (Doug McCarthy) was unable to make it, and so the guy I was watching (Bon Harris) was standing in for full vocal duties. This made the performance (and their subsequent one at Hellfest the week after) all the more impressive.

pic of the band
Via (with crab hat), Sarah, me (behind). pic by kraw

Via (with crab hat), Sarah, me (behind). pic by kraw

(Day) and night one, Thursday, was very hot and sunny and the band seemed a little uncomfortable exposed on stage with little cover. Trent commented as such at least once. The setlist was eclectic: and I finally heard some of my white whale songs. Highlights for me were The Perfect Drug, which was unplayed from 1997-2018 and has now become a staple, and the second ever performance of Everything, the first being a few days earlier. Also notable was three cuts in a row from the last LP, Bad Witch, Heresy and Love Is Not Enough.

Saturday 18th (rain)

with Elliot, before

with Elliot, before

Day/night 2, Friday, was rainy all day. Support was Yves Tumor, who were an interesting clash of styles: a Prince/Bowie-esque inspired lead clashing with a rock-out lead guitarist styling himself similarly to Brian May.

I managed to find Sarah, Elliot (new gig best-buddy), Via and James (sheapdean) again. Pete was at this gig too, but opted to take a more relaxed position than the rail this time. I also spent a lot of time talking to a Canadian guy on a press pass (both nights) that I'm ashamed to have forgotten his name.

The dank weather had Nine Inch Nails in their element. I think night one had the more interesting setlist, but night two had the best performance, hands down. Highlights for me were mostly a string of heavier songs (in rough order of scarcity, from common to rarely played): wish, burn, letting you, reptile, every day is exactly the same, the line begins to blur, and finally, happiness in slavery, the first UK performance since 1994. This was a crushing set.

A girl in front of me was really suffering with the cold and rain after waiting at the venue all day to get a position on the rail. I thought she was going to pass out. A roadie with NIN noticed, and came over and gave her his jacket. He said if she waited to the end of the show and returned his jacket he'd give her a setlist, and true to his word, he did. This was a really nice thing to happen and really gave the impression that the folks who work on these shows are caring people.

Yep I was this close

Yep I was this close

A fuckin' rainbow! Photo by "Lazereth of Nazereth"

Afterwards

Afterwards

Night two did have some gentler songs and moments to remember: a re-arranged Sanctified (which ended a nineteen-year hiatus in 2013) And All That Could Have Been (recorded 2002, first played 2018), La Mer, during which the rain broke and we were presented with a beautiful pink-hued rainbow. They then segued into Less Than, providing the comic moment of the night when Trent noticed the rainbow mid-song; now a meme that will go down in NIN fan history.

Wrap-up

This was a blow-out, once in a lifetime trip to go and see a band who are at the top of their career in terms of performance. One problem I've had with NIN gigs in the past is suffering gig flashback to them when I go to other (inferior) gigs afterwards, and I'm pretty sure I will have this problem again. Doing both nights was worth it, the two experiences were very different and each had its own unique moments. The venue was incredible, and Cornwall is (modulo tourist trap stuff) beautiful.

22 September, 2022 10:09AM

September 20, 2022

Simon Josefsson

Privilege separation of GSS-API credentials for Apache

To protect web resources with Kerberos you may use Apache HTTPD with mod_auth_gssapi — however, all web scripts (e.g., PHP) run under Apache will have access to the Kerberos long-term symmetric secret credential (keytab). If someone can get it, they can impersonate your server, which is bad.

The gssproxy project makes it possible to introduce privilege separation to reduce the attack surface. There is a tutorial for RPM-based distributions (Fedora, RHEL, AlmaLinux, etc), but I wanted to get this to work on a DPKG-based distribution (Debian, Ubuntu, Trisquel, PureOS, etc) and found it worthwhile to document the process. I’m using Ubuntu 22.04 below, but have tested it on Debian 11 as well. I have adopted the gssproxy package in Debian, and testing this setup is part of the scripted autopkgtest/debci regression testing.

First install the required packages:

root@foo:~# apt-get update
root@foo:~# apt-get install -y apache2 libapache2-mod-auth-gssapi gssproxy curl

This should give you a working and running web server. Verify it is operational under the proper hostname, I’ll use foo.sjd.se in this writeup.

root@foo:~# curl --head http://foo.sjd.se/
HTTP/1.1 200 OK
…

The next step is to create a keytab containing the Kerberos V5 secrets for your host, the exact steps depends on your environment (usually kadmin ktadd or ipa-getkeytab), but use the string “HTTP/foo.sjd.se” and then confirm using something like the following.

root@foo:~# ls -la /etc/gssproxy/httpd.keytab
-rw------- 1 root root 176 Sep 18 06:44 /etc/gssproxy/httpd.keytab
root@foo:~# klist -k /etc/gssproxy/httpd.keytab -e
Keytab name: FILE:/etc/gssproxy/httpd.keytab
KVNO Principal
---- --------------------------------------------------------------------------
   2 HTTP/foo.sjd.se@GSSPROXY.EXAMPLE.ORG (aes256-cts-hmac-sha1-96) 
   2 HTTP/foo.sjd.se@GSSPROXY.EXAMPLE.ORG (aes128-cts-hmac-sha1-96) 
root@foo:~#

The file should be owned by root and not be in the default /etc/krb5.keytab location, so Apache’s libapache2-mod-auth-gssapi will have to use gssproxy to use it.

Then configure gssproxy to find the credential and use it with Apache.

root@foo:~# cat<<EOF > /etc/gssproxy/80-httpd.conf
[service/HTTP]
mechs = krb5
cred_store = keytab:/etc/gssproxy/httpd.keytab
cred_store = ccache:/var/lib/gssproxy/clients/krb5cc_%U
euid = www-data
process = /usr/sbin/apache2
EOF

For debugging, it may be useful to enable more gssproxy logging:

root@foo:~# cat<<EOF > /etc/gssproxy/gssproxy.conf
[gssproxy]
debug_level = 1
EOF
root@foo:~#

Restart gssproxy so it finds the new configuration, and monitor syslog as follows:

root@foo:~# tail -F /var/log/syslog &
root@foo:~# systemctl restart gssproxy

You should see something like this in the log file:

Sep 18 07:03:15 foo gssproxy[4076]: [2022/09/18 05:03:15]: Exiting after receiving a signal
Sep 18 07:03:15 foo systemd[1]: Stopping GSSAPI Proxy Daemon…
Sep 18 07:03:15 foo systemd[1]: gssproxy.service: Deactivated successfully.
Sep 18 07:03:15 foo systemd[1]: Stopped GSSAPI Proxy Daemon.
Sep 18 07:03:15 foo gssproxy[4092]: [2022/09/18 05:03:15]: Debug Enabled (level: 1)
Sep 18 07:03:15 foo systemd[1]: Starting GSSAPI Proxy Daemon…
Sep 18 07:03:15 foo gssproxy[4093]: [2022/09/18 05:03:15]: Kernel doesn't support GSS-Proxy (can't open /proc/net/rpc/use-gss-proxy: 2 (No such file or directory))
Sep 18 07:03:15 foo gssproxy[4093]: [2022/09/18 05:03:15]: Problem with kernel communication! NFS server will not work
Sep 18 07:03:15 foo systemd[1]: Started GSSAPI Proxy Daemon.
Sep 18 07:03:15 foo gssproxy[4093]: [2022/09/18 05:03:15]: Initialization complete.

The NFS-related errors is due to a default gssproxy configuration file, it is harmless and if you don’t use NFS with GSS-API you can silence it like this:

root@foo:~# rm /etc/gssproxy/24-nfs-server.conf
root@foo:~# systemctl try-reload-or-restart gssproxy

The log should now indicate that it loaded the keytab:

Sep 18 07:18:59 foo systemd[1]: Reloading GSSAPI Proxy Daemon…
Sep 18 07:18:59 foo gssproxy[4182]: [2022/09/18 05:18:59]: Received SIGHUP; re-reading config.
Sep 18 07:18:59 foo gssproxy[4182]: [2022/09/18 05:18:59]: Service: HTTP, Keytab: /etc/gssproxy/httpd.keytab, Enctype: 18
Sep 18 07:18:59 foo gssproxy[4182]: [2022/09/18 05:18:59]: New config loaded successfully.
Sep 18 07:18:59 foo systemd[1]: Reloaded GSSAPI Proxy Daemon.

To instruct Apache — or actually, the MIT Kerberos V5 GSS-API library used by mod_auth_gssap loaded by Apache — to use gssproxy instead of using /etc/krb5.keytab as usual, Apache needs to be started in an environment that has GSS_USE_PROXY=1 set. The background is covered by the gssproxy-mech(8) man page and explained by the gssproxy README.

When systemd is used the following can be used to set the environment variable, note the final command to reload systemd.

root@foo:~# mkdir -p /etc/systemd/system/apache2.service.d
root@foo:~# cat<<EOF > /etc/systemd/system/apache2.service.d/gssproxy.conf
[Service]
Environment=GSS_USE_PROXY=1
EOF
root@foo:~# systemctl daemon-reload

The next step is to configure a GSS-API protected Apache resource:

root@foo:~# cat<<EOF > /etc/apache2/conf-available/private.conf
<Location /private>
  AuthType GSSAPI
  AuthName "GSSAPI Login"
  Require valid-user
</Location>

Enable the configuration and restart Apache — the suggested use of reload is not sufficient, because then it won’t be restarted with the newly introduced GSS_USE_PROXY variable. This just applies to the first time, after the first restart you may use reload again.

root@foo:~# a2enconf private
Enabling conf private.
To activate the new configuration, you need to run:
systemctl reload apache2
root@foo:~# systemctl restart apache2

When you have debug messages enabled, the log may look like this:

Sep 18 07:32:23 foo systemd[1]: Stopping The Apache HTTP Server…
Sep 18 07:32:23 foo gssproxy[4182]: [2022/09/18 05:32:23]: Client [2022/09/18 05:32:23]: (/usr/sbin/apache2) [2022/09/18 05:32:23]: connected (fd = 10)[2022/09/18 05:32:23]: (pid = 4651) (uid = 0) (gid = 0)[2022/09/18 05:32:23]:
Sep 18 07:32:23 foo gssproxy[4182]: message repeated 4 times: [ [2022/09/18 05:32:23]: Client [2022/09/18 05:32:23]: (/usr/sbin/apache2) [2022/09/18 05:32:23]: connected (fd = 10)[2022/09/18 05:32:23]: (pid = 4651) (uid = 0) (gid = 0)[2022/09/18 05:32:23]:]
Sep 18 07:32:23 foo systemd[1]: apache2.service: Deactivated successfully.
Sep 18 07:32:23 foo systemd[1]: Stopped The Apache HTTP Server.
Sep 18 07:32:23 foo systemd[1]: Starting The Apache HTTP Server…
Sep 18 07:32:23 foo gssproxy[4182]: [2022/09/18 05:32:23]: Client [2022/09/18 05:32:23]: (/usr/sbin/apache2) [2022/09/18 05:32:23]: connected (fd = 10)[2022/09/18 05:32:23]: (pid = 4657) (uid = 0) (gid = 0)[2022/09/18 05:32:23]:
root@foo:~# Sep 18 07:32:23 foo gssproxy[4182]: message repeated 8 times: [ [2022/09/18 05:32:23]: Client [2022/09/18 05:32:23]: (/usr/sbin/apache2) [2022/09/18 05:32:23]: connected (fd = 10)[2022/09/18 05:32:23]: (pid = 4657) (uid = 0) (gid = 0)[2022/09/18 05:32:23]:]
Sep 18 07:32:23 foo systemd[1]: Started The Apache HTTP Server.

Finally, set up a dummy test page on the server:

root@foo:~# echo OK > /var/www/html/private

To verify that the server is working properly you may acquire tickets locally and then use curl to retrieve the GSS-API protected resource. The "--negotiate" enables SPNEGO and "--user :" asks curl to use username from the environment.

root@foo:~# klist
Ticket cache: FILE:/tmp/krb5cc_0
Default principal: jas@GSSPROXY.EXAMPLE.ORG

Valid starting Expires Service principal
09/18/22 07:40:37 09/19/22 07:40:37 krbtgt/GSSPROXY.EXAMPLE.ORG@GSSPROXY.EXAMPLE.ORG
root@foo:~# curl --negotiate --user : http://foo.sjd.se/private
OK
root@foo:~#

The log should contain something like this:

Sep 18 07:56:00 foo gssproxy[4872]: [2022/09/18 05:56:00]: Client [2022/09/18 05:56:00]: (/usr/sbin/apache2) [2022/09/18 05:56:00]: connected (fd = 10)[2022/09/18 05:56:00]: (pid = 5042) (uid = 33) (gid = 33)[2022/09/18 05:56:00]:
Sep 18 07:56:00 foo gssproxy[4872]: [CID 10][2022/09/18 05:56:00]: gp_rpc_execute: executing 6 (GSSX_ACQUIRE_CRED) for service "HTTP", euid: 33,socket: (null)
Sep 18 07:56:00 foo gssproxy[4872]: [CID 10][2022/09/18 05:56:00]: gp_rpc_execute: executing 6 (GSSX_ACQUIRE_CRED) for service "HTTP", euid: 33,socket: (null)
Sep 18 07:56:00 foo gssproxy[4872]: [CID 10][2022/09/18 05:56:00]: gp_rpc_execute: executing 1 (GSSX_INDICATE_MECHS) for service "HTTP", euid: 33,socket: (null)
Sep 18 07:56:00 foo gssproxy[4872]: [CID 10][2022/09/18 05:56:00]: gp_rpc_execute: executing 6 (GSSX_ACQUIRE_CRED) for service "HTTP", euid: 33,socket: (null)
Sep 18 07:56:00 foo gssproxy[4872]: [CID 10][2022/09/18 05:56:00]: gp_rpc_execute: executing 9 (GSSX_ACCEPT_SEC_CONTEXT) for service "HTTP", euid: 33,socket: (null)

The Apache log will look like this, notice the authenticated username shown.

127.0.0.1 - jas@GSSPROXY.EXAMPLE.ORG [18/Sep/2022:07:56:00 +0200] "GET /private HTTP/1.1" 200 481 "-" "curl/7.81.0"

Congratulations, and happy hacking!

20 September, 2022 06:40AM by simon

hackergotchi for Matthew Garrett

Matthew Garrett

Handling WebAuthn over remote SSH connections

Being able to SSH into remote machines and do work there is great. Using hardware security tokens for 2FA is also great. But trying to use them both at the same time doesn't work super well, because if you hit a WebAuthn request on the remote machine it doesn't matter how much you mash your token - it's not going to work.

But could it?

The SSH agent protocol abstracts key management out of SSH itself and into a separate process. When you run "ssh-add .ssh/id_rsa", that key is being loaded into the SSH agent. When SSH wants to use that key to authenticate to a remote system, it asks the SSH agent to perform the cryptographic signatures on its behalf. SSH also supports forwarding the SSH agent protocol over SSH itself, so if you SSH into a remote system then remote clients can also access your keys - this allows you to bounce through one remote system into another without having to copy your keys to those remote systems.

More recently, SSH gained the ability to store SSH keys on hardware tokens such as Yubikeys. If configured appropriately, this means that even if you forward your agent to a remote site, that site can't do anything with your keys unless you physically touch the token. But out of the box, this is only useful for SSH keys - you can't do anything else with this support.

Well, that's what I thought, at least. And then I looked at the code and realised that SSH is communicating with the security tokens using the same library that a browser would, except it ensures that any signature request starts with the string "ssh:" (which a genuine WebAuthn request never will). This constraint can actually be disabled by passing -O no-restrict-websafe to ssh-agent, except that was broken until this weekend. But let's assume there's a glorious future where that patch gets backported everywhere, and see what we can do with it.

First we need to load the key into the security token. For this I ended up hacking up the Go SSH agent support. Annoyingly it doesn't seem to be possible to make calls to the agent without going via one of the exported methods here, so I don't think this logic can be implemented without modifying the agent module itself. But this is basically as simple as adding another key message type that looks something like:
type ecdsaSkKeyMsg struct {
       Type        string `sshtype:"17|25"`
       Curve       string
       PubKeyBytes []byte
       RpId        string
       Flags       uint8
       KeyHandle   []byte
       Reserved    []byte
       Comments    string
       Constraints []byte `ssh:"rest"`
}
Where Type is ssh.KeyAlgoSKECDSA256, Curve is "nistp256", RpId is the identity of the relying party (eg, "webauthn.io"), Flags is 0x1 if you want the user to have to touch the key, KeyHandle is the hardware token's representation of the key (basically an opaque blob that's sufficient for the token to regenerate the keypair - this is generally stored by the remote site and handed back to you when it wants you to authenticate). The other fields can be ignored, other than PubKeyBytes, which is supposed to be the public half of the keypair.

This causes an obvious problem. We have an opaque blob that represents a keypair. We don't have the public key. And OpenSSH verifies that PubKeyByes is a legitimate ecdsa public key before it'll load the key. Fortunately it only verifies that it's a legitimate ecdsa public key, and does nothing to verify that it's related to the private key in any way. So, just generate a new ECDSA key (ecdsa.GenerateKey(elliptic.P256(), rand.Reader)) and marshal it ( elliptic.Marshal(ecKey.Curve, ecKey.X, ecKey.Y)) and we're good. Pass that struct to ssh.Marshal() and then make an agent call.

Now you can use the standard agent interfaces to trigger a signature event. You want to pass the raw challenge (not the hash of the challenge!) - the SSH code will do the hashing itself. If you're using agent forwarding this will be forwarded from the remote system to your local one, and your security token should start blinking - touch it and you'll get back an ssh.Signature blob. ssh.Unmarshal() the Blob member to a struct like
type ecSig struct {
        R *big.Int
        S *big.Int
}
and then ssh.Unmarshal the Rest member to
type authData struct {
        Flags    uint8
        SigCount uint32
}
The signature needs to be converted back to a DER-encoded ASN.1 structure (eg,
var b cryptobyte.Builder
b.AddASN1(asn1.SEQUENCE, func(b *cryptobyte.Builder) {
        b.AddASN1BigInt(ecSig.R)
        b.AddASN1BigInt(ecSig.S)
})
signatureDER, _ := b.Bytes()
, and then you need to construct the Authenticator Data structure. For this, take the RpId used earlier and generate the sha256. Append the one byte Flags variable, and then convert SigCount to big endian and append those 4 bytes. You should now have a 37 byte structure. This needs to be CBOR encoded (I used github.com/fxamacker/cbor and just called cbor.Marshal(data, cbor.EncOptions{})).

Now base64 encode the sha256 of the challenge data, the DER-encoded signature and the CBOR-encoded authenticator data and you've got everything you need to provide to the remote site to satisfy the challenge.

There are alternative approaches - you can use USB/IP to forward the hardware token directly to the remote system. But that means you can't use it locally, so it's less than ideal. Or you could implement a proxy that communicates with the key locally and have that tunneled through to the remote host, but at that point you're just reinventing ssh-agent.

And you should bear in mind that the default behaviour of blocking this sort of request is for a good reason! If someone is able to compromise a remote system that you're SSHed into, they can potentially trick you into hitting the key to sign a request they've made on behalf of an arbitrary site. Obviously they could do the same without any of this if they've compromised your local system, but there is some additional risk to this. It would be nice to have sensible MAC policies that default-denied access to the SSH agent socket and only allowed trustworthy binaries to do so, or maybe have some sort of reasonable flatpak-style portal to gate access. For my threat model I think it's a worthwhile security tradeoff, but you should evaluate that carefully yourself.

Anyway. Now to figure out whether there's a reasonable way to get browsers to work with this.

comment count unavailable comments

20 September, 2022 02:17AM

September 19, 2022

Antoine Beaupré

Looking at Wayland terminal emulators

Back in 2018, I made a two part series about terminal emulators that was actually pretty painful to write. So I'm not going to retry this here, not at all. Especially since I'm not submitting this to the excellent LWN editors so I can get away with not being very good at writing. Phew.

Still, it seems my future self will thank me for collecting my thoughts on the terminal emulators I have found out about since I wrote that article. Back then, Wayland was not quite at the level where it is now, being the default in Fedora (2016), Debian (2019), RedHat (2019), and Ubuntu (2021). Also, a bunch of folks thought they would solve everything by using OpenGL for rendering. Let's see how things stack up.

Recap

In the previous article, I touched on those projects:

Terminal Changes since review
Alacritty releases! scrollback, better latency, URL launcher, clipboard support, still not in Debian, but close
GNOME Terminal not much? couldn't find a changelog
Konsole outdated changelog, color, image previews, clickable files, multi-input, SSH plugin, sixel images
mlterm long changelog but: supports console mode (like GNU screen?!), Wayland support through libvte, sixel graphics, zmodem, mosh (!)
pterm changes: Wayland support
st unparseable changelog, suggests scroll(1) or scrollback.patch for scrollback now
Terminator moved to GitHub, Python 3 support, not being dead
urxvt no significant changes, a single release, still in CVS!
Xfce Terminal hard to parse changelog, presumably some improvements to paste safety?
xterm notoriously hard to parse changelog, improvements to paste safety (disallowedPasteControls), fonts, clipboard improvements?

After writing those articles, bizarrely, I was still using rxvt even though it did not come up as shiny as I would have liked. The colors problems were especially irritating.

I briefly played around with Konsole and xterm, and eventually switched to XTerm as my default x-terminal-emulator "alternative" in my Debian system, while writing this.

I quickly noticed why I had stopped using it: clickable links are a huge limitation. I ended up adding keybindings to open URLs in a command. There's another keybinding to dump the history into a command. Neither are as satisfactory as just clicking a damn link.

Requirements

Figuring out my requirements is actually a pretty hard thing to do. In my last reviews, I just tried a bunch of stuff and collected everything, but a lot of things (like tab support) I don't actually care about. So here's a set of things I actually do care about:

  • latency
  • resource usage
  • proper clipboard support, that is:
    • mouse selection and middle button uses PRIMARY
    • control-shift-c and control-shift-v for CLIPBOARD
  • true color support
  • no known security issues
  • active project
  • paste protection
  • clickable URLs
  • scrollback
  • font resize
  • non-destructive text-wrapping (ie. resizing a window doesn't drop scrollback history)
  • proper unicode support (at least latin-1, ideally "everything")
  • good emoji support (at least showing them, ideally "nicely"), which involves font fallback

Latency is particularly something I wonder about in Wayland. Kitty seem to have been pretty dilligent at doing latency tests, claiming 35ms with a hardware-based latency tester and 7ms with typometer, but it's unclear how those would come up in Wayland because, as far as I know, typometer does not support Wayland.

Candidates

Those are the projects I am considering.

  • darktile - GPU rendering, Unicode support, themable, ligatures (optional), Sixel, window transparency, clickable URLs, true color support, not in Debian
  • foot - Wayland only, daemon-mode, sixel images, scrollback search, true color, font resize, URLs not clickable, but keyboard-driven selection, proper clipboard support, in Debian
  • havoc - minimal, scrollback, configurable keybindings, not in Debian
  • sakura - libvte, Wayland support, tabs, no menu bar, original libvte gangster, dynamic font size, probably supports Wayland, in Debian
  • termonad - Haskell? in Debian
  • wez - Rust, Wayland, multiplexer, ligatures, scrollback search, clipboard support, bracketed paste, panes, tabs, serial port support, Sixel, Kitty, iTerm graphics, built-in SSH client (!?), not in Debian
  • XTerm - status quo, no Wayland port obviously
  • zutty: OpenGL rendering, true color, clipboard support, small codebase, no Wayland support, crashes on bremner's, in Debian

Candidates not considered

Alacritty

I would really, really like to use Alacritty, but it's still not packaged in Debian, and they haven't fully addressed the latency issues although, to be fair, maybe it's just an impossible task. Once it's packaged in Debian, maybe I'll reconsider.

Kitty

Kitty is a "fast, feature-rich, GPU based", with ligatures, emojis, hyperlinks, pluggable, scriptable, tabs, layouts, history, file transfer over SSH, its own graphics system, and probably much more I'm forgetting. It's packaged in Debian.

So I immediately got two people commenting (on IRC) that they use Kitty and are pretty happy with it. I've been hesitant in directly talking about Kitty publicly, but since it's likely there will be a pile-up of similar comments, I'll just say why it's not the first in my list, even if it might, considering it's packaged in Debian and otherwise checks all the boxes.

I don't trust the Kitty code. Kitty was written by the same author as Calibre, which has a horrible security history and generally really messy source code. I have tried to do LTS work on Calibre, and have mostly given up on the idea of making that program secure in any way. See calibre for the details on that.

Now it's possible Kitty is different: it's quite likely the author has gotten some experience writing (and maintaining for so long!) Calibre over the years. But I would be more optimistic if the author's reaction to the security issues were more open and proactive.

I've also seen the same reaction play out on Kitty's side of things. As anyone who worked on writing or playing with non-XTerm terminal emulators, it's quite a struggle to make something (bug-for-bug) compatible with everything out there. And Kitty is in that uncomfortable place right now where it diverges from the canon and needs its own entry in the ncurses database. I don't remember the specifics, but the author also managed to get into fights with those people as well, which I don't feel is reassuring for the project going forward.

If security and compatibility wasn't such big of a deal for me, I wouldn't mind so much, but I'll need a lot of convincing before I consider Kitty more seriously at this point.

Next steps

It seems like Arch Linux defaults to foot in Sway, and I keep seeing it everywhere, so it is probably my next thing to try, if/when I switch to Wayland.

One major problem with foot is that it's yet another terminfo entry. They did make it into ncurses (patch 2021-07-31) but only after Debian bullseye stable was released. So expect some weird compatibility issues when connecting to any other system that is older or the same as stable (!).

One question mark with all Wayland terminals, and Foot in particular, is how much latency they introduce in the rendering pipeline. The foot performance and benchmarks look excellent, but do not include latency benchmarks.

No conclusion

So I guess that's all I've got so far, I may try alacritty if it hits Debian, or foot if I switch to Wayland, but for now I'm hacking in xterm still. Happy to hear ideas in the comments.

Stay tuned for more happy days.

19 September, 2022 04:41PM

hackergotchi for Matthew Garrett

Matthew Garrett

Bring Your Own Disaster

After my last post, someone suggested that having employers be able to restrict keys to machines they control is a bad thing. So here's why I think Bring Your Own Device (BYOD) scenarios are bad not only for employers, but also for users.

There's obvious mutual appeal to having developers use their own hardware rather than rely on employer-provided hardware. The user gets to use hardware they're familiar with, and which matches their ergonomic desires. The employer gets to save on the money required to buy new hardware for the employee. From this perspective, there's a clear win-win outcome.

But once you start thinking about security, it gets more complicated. If I, as an employer, want to ensure that any systems that can access my resources meet a certain security baseline (eg, I don't want my developers using unpatched Windows ME), I need some of my own software installed on there. And that software doesn't magically go away when the user is doing their own thing. If a user lends their machine to their partner, is the partner fully informed about what level of access I have? Are they going to feel that their privacy has been violated if they find out afterwards?

But it's not just about monitoring. If an employee's machine is compromised and the compromise is detected, what happens next? If the employer owns the system then it's easy - you pick up the device for forensic analysis and give the employee a new machine to use while that's going on. If the employee owns the system, they're probably not going to be super enthusiastic about handing over a machine that also contains a bunch of their personal data. In much of the world the law is probably on their side, and even if it isn't then telling the employee that they have a choice between handing over their laptop or getting fired probably isn't going to end well.

But obviously this is all predicated on the idea that an employer needs visibility into what's happening on systems that have access to their systems, or which are used to develop code that they'll be deploying. And I think it's fair to say that not everyone needs that! But if you hold any sort of personal data (including passwords) for any external users, I really do think you need to protect against compromised employee machines, and that does mean having some degree of insight into what's happening on those machines. If you don't want to deal with the complicated consequences of allowing employees to use their own hardware, it's rational to ensure that only employer-owned hardware can be used.

But what about the employers that don't currently need that? If there's no plausible future where you'll host user data, or where you'll sell products to others who'll host user data, then sure! But if that might happen in future (even if it doesn't right now), what's your transition plan? How are you going to deal with employees who are happily using their personal systems right now? At what point are you going to buy new laptops for everyone? BYOD might work for you now, but will it always?

And if your employer insists on employees using their own hardware, those employees should ask what happens in the event of a security breach. Whose responsibility is it to ensure that hardware is kept up to date? Is there an expectation that security can insist on the hardware being handed over for investigation? What information about the employee's use of their own hardware is going to be logged, who has access to those logs, and how long are those logs going to be kept for? If those questions can't be answered in a reasonable way, it's a huge red flag. You shouldn't have to give up your privacy and (potentially) your hardware for a job.

Using technical mechanisms to ensure that employees only use employer-provided hardware is understandably icky, but it's something that allows employers to impose appropriate security policies without violating employee privacy.

comment count unavailable comments

19 September, 2022 07:12AM

hackergotchi for Axel Beckert

Axel Beckert

wApua 0.06.4 released

I today released version 0.06.4 of my WAP WML browser wApua and also uploaded that release to Debian Unstable.

It’s a bugfix release and the first upstream release since 2017.

It fixes the recognition of WAP WML pages with more recent DTD location URLs ending in .dtd instead of .xml (and some other small difference). No idea when these URLs changed, but I assume they have been changed to look more like the URLs of other DTDs. The old URLs of the DTD still work, but more recent WAP pages (yes, they do exist :-) seem to use the new DTD URLs, so there was a need to recognise them instead of throwing an annoying warning.

Thanks to Lian Begett for the bug report!

19 September, 2022 12:55AM by Axel Beckert (abe+blog@deuxchevaux.org)

September 17, 2022

Russ Allbery

Effective altruism and the control trap

William MacAskill has been on a book tour for What We Owe to the Future, which has put effective altruism back in the news. That plus the decision by GiveWell to remove GiveDirectly from their top charity list got me thinking about charity again. I think effective altruism, by embracing long-termism, is falling into an ethical trap, and I'm going to start heavily discounting their recommendations for donations.

Background

Some background first for people who have no idea what I'm talking about.

Effective altruism is the idea that we should hold charities accountable for effectiveness. It's not sufficient to have an appealing mission. A charity should demonstrate that the money they spend accomplishes the goals they claimed it would. There is a lot of debate around defining "effective," but as a basic principle, this is sound. Mainstream charity evaluators such as Charity Navigator measure overhead and (arguable) waste, but they don't ask whether the on-the-ground work of the charity has a positive effect proportional to the resources it's expending. This is a good question to ask.

GiveWell is a charity research organization that directs money for donors based on effective altruism principles. It's one of the central organizations in effective altruism.

GiveDirectly is a charity that directly transfers money from donors to poor people. It doesn't attempt to build infrastructure, buy specific things, or fund programs. It identifies poor people and gives them cash with no strings attached.

Long-termism is part of the debate over what "effectiveness" means. It says we should value impact on future generations more highly than we tend to do. (In other words, we should have a much smaller future discount rate.) A sloppy but intuitive expression of long-termism is that (hopefully) there will be far more humans living in the future than are living today, and therefore a "greatest good for the greatest number" moral philosophy argues that we should invest significant resources into making the long-term future brighter. This has obvious appeal to those of us who are concerned about the long-term impacts of climate change, for example.

There is a lot of overlap between the communities of effective altruism, long-termism, and "rationalism." One way this becomes apparent is that all three communities have a tendency to obsess over the risks of sentient AI taking over the world. I'm going to come back to that.

Psychology of control

GiveWell, early on, discovered that GiveDirectly was measurably more effective than most charities. Giving money directly to poor people without telling them how to spend it produced more benefits for those people and their surrounding society than nearly all international aid charities.

GiveDirectly then became the baseline for GiveWell's evaluations, and GiveWell started looking for ways to be more effective than that. There is some logic to thinking more effectiveness is possible. Some problems are poorly addressed by markets and too large for individual spending. Health care infrastructure is an obvious example.

That said, there's also a psychological reason to look for other charities. Part of the appeal of charity is picking a cause that supports your values (whether that be raw effectiveness or something else). Your opinions and expertise are valued alongside your money. In some cases, this may be objectively true. But in all cases, it's more flattering to the ego than giving poor people cash.

At that point, the argument was over how to address immediate and objectively measurable human problems. The innovation of effective altruism is to tie charitable giving to a research feedback cycle. You measure the world, see if it is improving, and adjust your funding accordingly. Impact is measured by its effects on actual people. Effective altruism was somewhat suspicious of talking directly to individuals and preferred "objective" statistical measures, but the point was to remain in contact with physical reality.

Enter long-termism: what if you could get more value for your money by addressing problems that would affect vast numbers of future people, instead of the smaller number of people who happen to be alive today?

Rather than looking at the merits of that argument, look at its psychology. Real people are messy. They do things you don't approve of. They have opinions that don't fit your models. They're hard to "objectively" measure. But people who haven't been born yet are much tidier. They're comfortably theoretical; instead of having to go to a strange place with unfamiliar food and languages to talk to people who aren't like you, you can think hard about future trends in the comfort of your home. You control how your theoretical future people are defined, so the results of your analysis will align with your philosophical and ideological beliefs.

Problems affecting future humans are still extrapolations of problems visible today in the world, though. They're constrained by observations of real human societies, despite the layer of projection and extrapolation. We can do better: what if the most serious problem facing humanity is the possible future development of rogue AI?

Here's a problem that no one can observe or measure because it's never happened. It is purely theoretical, and thus under the control of the smart philosopher or rich western donor. We don't know if a rogue AI is possible, what it would be like, how one might arise, or what we could do about it, but we can convince ourselves that all those things can be calculated with some probability bar through the power of pure logic. Now we have escaped the uncomfortable psychological tension of effective altruism and returned to the familiar world in which the rich donor can define both the problem and the solution. Effectiveness is once again what we say it is.

William MacAskill, one of the originators of effective altruism, now constantly talks about the threat of rogue AI. In a way, it's quite sad.

Where to give money?

The mindset of long-termism is bad for the human brain. It whispers to you that you're smarter than other people, that you know what's really important, and that you should retain control of more resources because you'll spend them more wisely than others. It's the opposite of intellectual humility. A government funding agency should take some risks on theoretical solutions to real problems, and maybe a few on theoretical solutions to theoretical problems (although an order of magnitude less). I don't think this is a useful way for an individual donor to think.

So, if I think effective altruism is abandoning the one good idea it had and turning back into psychological support for the egos of philosophers and rich donors, where does this leave my charitable donations?

To their credit, GiveWell so far seems uninterested in shifting from concrete to theoretical problems. However, they believe they can do better by picking projects than giving people money, and they're committing to that by dropping GiveDirectly (while still praising them). They may be right. But I'm increasingly suspicious of the level of control donors want to retain. It's too easy to trick oneself into thinking you know better than the people directly affected.

I have two goals when I donate money. One is to make the world a better, kinder place. The other is to redistribute wealth. I have more of something than I need, and it should go to someone who does need it. The net effect should be to make the world fairer and more equal.

The first goal argues for effective altruism principles: where can I give money to have the most impact on making the world better? The second goal argues for giving across an inequality gradient. I should find the people who are struggling the most and transfer as many resources to them as I can. This is Peter Singer's classic argument for giving money to the global poor.

I think one can sometimes do better than transferring money, but doing so requires a deep understanding of the infrastructure and economies of scale that are being used as leverage. The more distant one is from a society, the more dubious I think one should be of one's ability to evaluate that, and the more wary one should be of retaining any control over how resources are used.

Therefore, I'm pulling my recurring donation to GiveWell. Half of it is going to go to GiveDirectly, because I think it is an effective way of redistributing wealth while giving up control. The other half is going to my local foodbank, because they have a straightforward analysis of how they can take advantage of economy of scale, and because I have more tools available (such as local news) to understand what problem they're solving and if they're doing so effectively.

I don't know that those are the best choices. There are a lot of good ones. But I do feel strongly that the best charity comes from embracing the idea that I do not have special wisdom, other people know more about what they need than I do, and deploying my ego and logic from the comfort of my home is not helpful. Find someone who needs something you have an excess of. Give it to them. Treat them as equals. Don't retain control. You won't go far wrong.

17 September, 2022 08:49PM

hackergotchi for Shirish Agarwal

Shirish Agarwal

Books and Indian Tourism

Fiction

A few days ago somebody asked me and I think it is an often requested to perhaps all fiction readers as to why we like fiction? First of all, reading in itself is told as food for the soul. Because, whenever you write or read anything you don’t just read it, you also visualize it. And that visualization is and would be far greater than any attempt in cinema as there are no budget constraints and it takes no more than a minute to visualize a scenario if the writer is any good. You just close your eyes and in a moment you are transported to a different world. This is also what is known as ‘world building’. Something fantasy writers are especially gifted in. Also, with the whole parallel Universes being a reality, it is just so much fertile land for imagination that I just cannot believe that it hasn’t been worked to death to date. And you do need a lot of patience to make a world, to make characters, to make characters a bit eccentric one way or the other. And you have to know to put into a three, five, or whatever number of acts you want to put in. And then, of course, they have readers like us who dream and add more color to the story than the author did. As we take his, her, or their story and weave countless stories depending on where we are, where we are and who we are.

What people need to understand is that not just readers want escapism but writers too want to escape from the human condition. And they find solace in whatever they write. The well-known example of J.R.R. Tolkien is always there. How he must have felt each day coming after war, to somehow find the strength and just dream away, transport himself to a world of hobbits, elves, and other mysterious beings. It surely must have taken a lot of pain from him that otherwise, he would have felt. There are many others. What also does happen now and then, is authors believe in their own intelligence so much, that they commit crimes, but that’s par for the course.

Dean Koontz, Odd Apocalypse

Currently, I am reading the above title. It is perhaps one of the first horror title books that I have read which has so much fun. The ‘hero’ has a great sense of wit, humor, and sarcasm that you can cut butter with it. Now if you got that, this is par for the wordplay happening every second paragraph and I’m just 100 pages in of the 500-page Novel.

Now, while I haven’t read the whole book and I’m just speculating, what if at the end we realize that the hero all along was or is the villain. Sadly, we don’t have many such twisted stories and that too is perhaps because most people used to have black and white rather than grey characters. From all my reading, and even watching web series and whatnot, it is only the Europeans who seem to have a taste for exploring grey characters and giving twists at the end that people cannot anticipate. Even their heroes or heroines are grey characters. and they can really take you for a ride. It is also perhaps how we humans are, neither black nor white but more greyish. Having grey characters also frees the author quite a bit as she doesn’t have to use so-called tropes and just led the characters to lead themselves.

Indian Book publishing Industry

I do know Bengali stories do have a lot of grey characters, but sadly most of the good works are still in Bengali and not widely published compared to say European or American authors. While there is huge potential in the Indian publishing market for English books and there is also hunger, getting good and cheap publishers is the issue. Just recently SAGE publishing division shut down and this does not augur well for the Indian market. In the past few years, I and other readers have seen some very good publishing houses quit India for one reason or the other. GST has also made the sector more expensive. The only thing that works now and has been for some time is the seconds and thirds market. For e.g. I just bought today about 15-20 books @INR 125/- a kind of belated present for the self. That would be what, at the most 2 USD or 2 Euros per book. I bet even a burger costs more than that, but again India being a price-sensitive market, at these prices the seconds book sells. And these are all my favorite authors, Lee Child, Tom Clancy, Dean Koontz, and so on and so forth. I also saw a lot of fantasy books but they would have to wait for another day.

Tourism in India for Debconf 23

I had shared a while back that I would write a bit about tourism as Debconf or Annual Debian Conference will happen in India next year around this time. I was supposed to write it in the FAQ but couldn’t find a place or a corner where I could write it. There are actually two things that people need to be aware of. The one thing that people need to be very aware of is food poisoning or Delhi Belly. This is a far too common sight that I have witnessed especially with westerners when they come to visit India. I am somewhat shocked that it hasn’t been shared in the FAQ but then perhaps we cannot cover all the bases therein. I did find this interesting article and would recommend the suggestions given in it wholeheartedly. I would suggest people coming to India to buy and have purifying water tablets with them if they decide to stay back and explore India.

Now the problem with tourism is, that one can have as much tourism as one wants. One of the unique ways I found some westerners having the time of their life is buying an Indian Rickshaw or Tuk-Tuk and traveling with it. A few years ago, when I was more adventourous-spirited I was able to meet a few of them. There is also the Race with Rickshaws that happens in Rajasthan and you get to see about 10 odd cities in and around Rajasthan state and get to see the vibrancy in the North. If somebody really wants to explore India, then I would suggest getting down to Goa, specifically, South Goa, meeting with the hippie crowd, and getting one of the hippie guidebooks to India. Most people forget that the Hippies came to India in the 1960s and many of them just never left. Tap water in Pune is ok, have seen and experienced the same in Himachal, Garwhal, and Uttarakhand, although it has been a few years since I have been to those places. North-East is a place I have yet to venture into.

India does have a lot of beauty but most people are not clean-conscious so if you go to common tourist destinations, you will find a lot of garbage. Most cities in India do give you an option of homestays and some even offer food, so if you are on a budget as well as wanna experience life with an Indian family, that could be something you could look into. So you can see and share about India with different eyes.

There is casteism, racism, and all that. Generally speaking, you would see it wielded a lot more in your face in North India than in South India where it is there but far more subtle. About food, what has been shared in the India BOF. Have to say, it doesn’t even scratch the surface. If you stay with an Indian family, there is probably a much better chance of exploring the variety of food that India has to offer. From the western perspective, we tend to overcook stuff and make food with Masalas but that’s the way most people like it. People who have had hot sauces or whatnot would probably find India much easier to adjust to as tastes might be similar to some extent.

If you want to socialize with young people, while discos are an option, meetup.com also is a good place. You can share your passions and many people have taken to it with gusto. We also have been hosting Comiccons in India, but I haven’t had the opportunity to attend them so far. India has a rich oral culture reach going back a few thousand years, but many of those who are practicing those reside more in villages rather than in cities. And while there have been attempts in the past to record them, most of those have come to naught as money runs out as there is no commercial viability to such projects, but that probably is for another day.

In the end, what I have shared is barely a drop in the ocean that is India. Come, have fun, explore, enjoy and invigorate yourself and others 🙂

17 September, 2022 07:32PM by shirishag75

James Valleroy

How I avoid sysadmin work

The server running this blog is a RockPro64 sitting in my living room. Besides WordPress (the blogging software), I run various other services on it:

  • Bepasty for sharing files,
  • Ikiwiki for taking notes,
  • Quassel for staying connected to IRC chat servers,
  • Radicale for synchronizing my calendar and tasks,
  • Shaarli for sharing bookmarks, and
  • Tiny Tiny RSS for reading other people’s blogs.

Most of these are for my personal use, and a few of them have pages for public viewing (linked at the top of this page).

Despite running a server, I don’t really consider myself to be a system administrator (or “sysadmin” for short). I generally try to avoid doing system administration work as much as possible. I think this is due to a number of reasons:

  • It is not part of my educational or professional background (which mainly consists of embedded software engineering).
  • I think that I lack the kind of discipline needed to be a sysadmin. For example, taking notes of the commands that you are running, or testing things before you do them on a production server. I’m likely to just run commands, and lose track of my notes.
  • And finally a type of laziness. I just don’t want to spend a lot of time and effort setting up or maintaining some services.

These reasons might be surprising to some, but they also suggest that an alternative approach:

  • I do have a server running in my home, but I don’t consider myself a sysadmin.
  • I have a different kind of discipline than the one I described above.
  • I’m willing to spend time and effort to improve things, but I want to do it in a different way than usual.

So my approach is this: if I want to run an additional service, enhance an existing one, or fix a bug, I don’t do those changes directly on my server. Instead, I will make (or suggest, or request) the change somewhere upstream of my server:

  • In the various Debian packages of the services I have installed.
  • In FreedomBox configuration and integration of those packages.
  • Or even directly to the upstream software development.

So basically my system administration task turns into a software development task instead. And (in my opinion) there are much better tools available for this: source control systems such as git, test suites and Continuous Integration (CI) pipelines, and code review processes. These make it easier to keep track of and understand the changes, and reduce the possibility of making a catastrophic mistake.

Besides this, there is one other major advantage to working upstream: the work is not just benefiting the server running in my home, but many others. Anyone who is using the same software or packages will also get the improvements or bug fixes. And likewise, I get to benefit from the work done by many other contributors.

Some final notes about this approach:

  • The software I am running is very standardized, specifically to what is available in Debian and FreedomBox. This limits the number of services available: for example, I could not easily run a Mastodon server with this approach. Also, I am not maintaining any custom configurations for my own services.
  • I am presenting these ideas as they occur to me, and specific to my situation. But there are similar concepts out there, for example “Infrastructure as Code”.

17 September, 2022 02:55PM by James Valleroy

hackergotchi for Jonathan Dowland

Jonathan Dowland

Prusa Mini

In June I caved and bought a Prusa Mini 3D printer for home. I bought it just before an announced price hike. I went for a Prusa because of their reputation for "just working", and the Mini mostly as its the cheapest, although, the print area (7"³) is large enough for most of the things I am likely to print.

Prusa Mini in its setting

To get started, at the same time I bought some Prusament recycled PLA to print with which, unfortunately, I've been a little disappointed with.

I was attracted to the idea of buying a recycled material and Prusa make a lot about the quality of their filaments.

The description was pretty clear that the colour would be somewhat random and vary throughout the spool, but I didn't mind that, and I planned to use it for mainly functional prints where the precise colour didn't matter. The colour examples from the product page were mostly off-white grey with some tint, typically green. There are not a lot of reviews of the recycled PLA that comment on the colour of their spools, but in a couple of youtube videos (1, 2) the spools have looked a grey-ish silver, sometimes with a greenish tint, pretty similar to the product page.

The colour I got is quite unlike those: it's a dull brown, with little flecks of glitter, presumably originally from recycling something like Galaxy Black. That's totally within "spec", of course, but it's a bit boring.

Brown recycled Prusament PLA on the right

Brown recycled Prusament PLA on the right

In terms of quality, sadly I've ended up with had at least one tangle in the spool wind so far. There's at least two reviews on their own product page from people who have had similar difficulties.

Edit:

I realised after I wrote this post that I hadn't actually written much about the printer. That's because I'm still in the early days of using it. In short I'd say it's a very high quality machine, very pleasant to use. Since I also went on a tangent about the recycled Prusament, the tone of the whole post was more negative than I intended. Watch this space for some more positive Prusa news soon!

17 September, 2022 07:56AM

Introducing Red Hat UBI9 OpenJDK runtime images

A few weeks ago we shipped the first RHEL UBI9-based OpenJDK container images.

Universal Base Image (UBI) is an initiative where you can obtain, share and build upon official Red Hat container images without needing a Red Hat subscription. They're exactly the same base images that Red Hat products are built upon, composed entirely of Open Source software. Your precise rights are covered in the EULA.

Nowadays we offer two flavours of images, the original style (now termed builder images) and leaner runtime images, which have a subset of the JDK, and no build tools like Maven, etc.

We provide JDK11 and JDK17 for UBI9:

podman pull registry.access.redhat.com/ubi9/openjdk-11
podman pull registry.access.redhat.com/ubi9/openjdk-17
podman pull registry.access.redhat.com/ubi9/openjdk-11-runtime
podman pull registry.access.redhat.com/ubi9/openjdk-17-runtime

In comparison to the UBI8 images, we have done a lot of housecleaning. If you are curious as to exactly what we've changed, you can read the list of commits in this pull request.

Perhaps most notable is a change in the way we tune the JVM's memory. In our existing images up to now, partially for legacy reasons, the container start up scripts interrogate the cgroups (v1) virtual filesystems to establish any memory limits imposed on the running container. From that, they calculated a percentage of the memory limit as an absolute value, and then ask the JVM to limit its heap to that calculated sum via the -Xmx flag.

This dates back to a time when the JVM was not container aware. It now is, so for the UBI9 images we instead ask the JVM directly for the percentage we want using -XX:MaxRAMPercentage. We've also changed the default percentage from 50% to 80%, to better utilise the memory assigned to Java containers.

One big advantage of this is the JVM is cgroups (v2) aware, and the legacy start up scripts we wrote are not. But another is reducing the amount of code we run in the start up scripts, easing maintenance and simplifying the containers as much as possible.

Please give them a go, and let me (or us) know what you think!

17 September, 2022 06:11AM

September 15, 2022

things I'd like to 3D print, revisited

Back in November I wrote up a list of 25 things I would 3D print. Let's revisit the list and see how things have developed.

Stuff I won't print

  • Some kind of 45° leaning prong to dry bottles and flasks on
  • A tea tray and coasters
  • Small tins to keep loose-leaf tea in

It was pointed out to me that you can't safely print things to store food in with most materials, as their porous/layered nature facilitates the growth of bacteria. So, I'll rule out those items.

A vinyl record.

The size of the grooves in a vinyl record are smaller than conventional FDM printers can achieve.

Things I've printed

a replacement prop arm/foot for my computer keyboard

Someone has modelled the exact part I need, and it worked great: https://www.printables.com/model/59132-lenovo-keyboard-kt-1255

replacement toy bolt

replacement toy bolt

replacement bits for an Early Learning Centre Build It Deluxe Set

I was amazed to find that someone has already modelled one of these, too, and it worked beautifully: https://www.printables.com/model/79243-elc-build-it-compatible-bolt

Little kids trinkets. Pacman ghosts

The Pacman ghost family so far

The Pacman ghost family so far

So far, I've tried to print useful, functional things, but on a few occasions I've printed a little Pacman ghost when testing printer calibration or similar. I've mostly used these models: https://www.printables.com/model/199425-pac-man-ghost-v2

  • Lego storage/sorters
  • DIY bits-and-bobs sorter/storage (nuts and bolts etc)

I learned about a Slicer setting sometimes called "Vase mode" and found this interesting system of modular drawers that are designed to be printed in Vase mode, so I gave them a go: https://www.printables.com/model/139570-fast-printing-modular-drawer-system-vase-mode I printed one and four drawers for it and gave it to my daughter. It might be used for sorting Lego, or possibly as a chest-of-drawers for a dolls house.

A free-standing inclined vinyl record display stand

https://www.printables.com/model/174711-vinyl-stand-for-kallax

A bracket to install a Gotek drive in my Amiga 500

https://www.thingiverse.com/thing:2745049

Summary

From my original list of 25 things to print, I've done 7 of them and determined 4 are not viable. The things in this list I've printed have been off-the-shelf models that other people have constructed. The things I haven't printed are designs I will do myself, which is one reason I haven't printed them yet: building your own designs is the hard part!

15 September, 2022 01:55PM

hackergotchi for Joachim Breitner

Joachim Breitner

rec-def: Dominators case study

More ICFP-inspired experiments using the rec-def library: In Norman Ramsey’s very nice talk about his Functional Pearl “Beyond Relooper: Recursive Translation of Unstructured Control Flow to Structured Control Flow”, he had the following slide showing the equation for the dominators of a node in a graph:

Norman Ramsey shows a formula Norman Ramsey shows a formula

He said “it’s ICFP and I wanted to say the dominance relation has a beautiful set of equations … you can read all these algorithms how to compute this, but the concept is simple”.

This made me wonder: If the concept is simple and this formula is beautiful – shouldn’t this be sufficient for the Haskell programmer to obtain the dominator relation, without reading all those algorithms?

Before we start, we have to clarify the formula a bit: If a node is an entry node (no predecessors) then the big intersection is over the empty set, and that is not a well-defined concept. For these nodes, we need that big intersection to return the empty set, as entry nodes are not dominated by any other node. (Let’s assume that the entry nodes are exactly those with no predecessors.)

Let’s try, first using plain Haskell data structures. We begin by implementing this big intersection operator on Data.Set, and also a function to find the predecessors of a node in a graph:

Now we can write down the formula that Norman gave, quite elegantly:

Does this work? It seems it does:

But – not surprising if you have read my previous blog posts – it falls over once we have recursion:

So let us reimplement it with Data.Recursive.Set.

The hope is that we can simply replace the operations, and that now it can suddenly handle cyclic graphs as well. Let’s see:

It does! Well, it does return a result… but it looks strange. Clearly node 3 and 4 are also dominated by 1, but the result does not reflect that.

But the result is a solution to Norman’s equation. Was the equation wrong? No, but we failed to notice that the desired solution is the largest, not the smallest. And Data.Recursive.Set calculates, as documented, the least fixed point.

What now? Until the library has code for RDualSet a, we can work around this by using the dual formula to calculate the non-dominators. To do this, we

  • use union instead of intersection
  • delete instead of insert,
  • S.empty, use the set of all nodes (which requires some extra plumbing)
  • subtract the result from the set of all nodes to get the dominators

and thus the code turns into:

And with this, now we do get the correct result:

ghci> domintors3 [(1,2),(1,3),(2,4),(3,4),(4,3)]
fromList [(1,[1]),(2,[1,2]),(3,[1,3]),(4,[1,4])]

We worked a little bit on how to express the “beautiful formula” to Haskell, but at no point did we have to think about how to solve it. To me, this is the essence of declarative programming.

15 September, 2022 08:27AM by Joachim Breitner (mail@joachim-breitner.de)

hackergotchi for Matthew Garrett

Matthew Garrett

git signatures with SSH certificates

Last night I complained that git's SSH signature format didn't support using SSH certificates rather than raw keys, and was swiftly corrected, once again highlighting that the best way to make something happen is to complain about it on the internet in order to trigger the universe to retcon it into existence to make you look like a fool. But anyway. Let's talk about making this work!

git's SSH signing support is actually just it shelling out to ssh-keygen with a specific set of options, so let's go through an example of this with ssh-keygen. First, here's my certificate:

$ ssh-keygen -L -f id_aurora-cert.pub
id_aurora-cert.pub:
Type: ecdsa-sha2-nistp256-cert-v01@openssh.com user certificate
Public key: ECDSA-CERT SHA256:(elided)
Signing CA: RSA SHA256:(elided)
Key ID: "mgarrett@aurora.tech"
Serial: 10505979558050566331
Valid: from 2022-09-13T17:23:53 to 2022-09-14T13:24:23
Principals:
mgarrett@aurora.tech
Critical Options: (none)
Extensions:
permit-agent-forwarding
permit-port-forwarding
permit-pty

Ok! Now let's sign something:

$ ssh-keygen -Y sign -f ~/.ssh/id_aurora-cert.pub -n git /tmp/testfile
Signing file /tmp/testfile
Write signature to /tmp/testfile.sig

To verify this we need an allowed signatures file, which should look something like:

*@aurora.tech cert-authority ssh-rsa AAA(elided)

Perfect. Let's verify it:

$ cat /tmp/testfile | ssh-keygen -Y verify -f /tmp/allowed_signers -I mgarrett@aurora.tech -n git -s /tmp/testfile.sig
Good "git" signature for mgarrett@aurora.tech with ECDSA-CERT key SHA256:(elided)

Woo! So, how do we make use of this in git? Generating the signatures is as simple as

$ git config --global commit.gpgsign true
$ git config --global gpg.format ssh
$ git config --global user.signingkey /home/mjg59/.ssh/id_aurora-cert.pub

and then getting on with life. Any commits will now be signed with the provided certificate. Unfortunately, git itself won't handle verification of these - it calls ssh-keygen -Y find-principals which doesn't deal with wildcards in the allowed signers file correctly, and then falls back to verifying the signature without making any assertions about identity. Which means you're going to have to implement this in your own CI by extracting the commit and the signature, extracting the identity from the commit metadata and calling ssh-keygen on your own. But it can be made to work!

But why would you want to? The current approach of managing keys for git isn't ideal - you can kind of piggy-back off github/gitlab SSH key infrastructure, but if you're an enterprise using SSH certificates for access then your users don't necessarily have enrolled keys to start with. And using certificates gives you extra benefits, such as having your CA verify that keys are hardware-backed before issuing a cert. Want to ensure that whoever made a commit was actually on an authorised laptop? Now you can!

I'll probably spend a little while looking into whether it's plausible to make the git verification code work with certificates or whether the right thing is to fix up ssh-keygen -Y find-principals to work with wildcard identities, but either way it's probably not much effort to get this working out of the box.

Edit to add: thanks to this commenter for pointing out that current OpenSSH git actually makes this work already!

comment count unavailable comments

15 September, 2022 01:34AM

September 14, 2022

hackergotchi for Joachim Breitner

Joachim Breitner

rec-def: Program analysis case study

At this week’s International Conference on Functional Programming I showed my rec-def Haskell library to a few people. As this crowd appreciates writing compilers, and example from the realm of program analysis is quite compelling.

To Throw or not to throw

Here is our little toy language to analyze: It has variables, lambdas and applications, non-recursive (lazy) let bindings and, so that we have something to analyze, a way to throw and to catch exceptions:

Given such an expression, we would like to know whether it might throw an exception. Such an analysis is easy to write: We traverse the syntax tree, remembering in the env which of the variables may throw an exception:

The most interesting case is the one for Let, where we extend the environment env with the information about the additional variable env_bind, which is calculated from analyzing the right-hand side e1.

So far so good:

ghci> someVal = Lam "y" (Var "y")
ghci> canThrow1 $ Throw
True
ghci> canThrow1 $ Let "x" Throw someVal
False
ghci> canThrow1 $ Let "x" Throw (App (Var "x") someVal)
True

Let it rec

To spice things up, let us add a recursive let to the language:

How can we support this new constructor in canThrow1? Let use naively follow the pattern used for Let: Calculate the analysis information for the variables in env_bind, extend the environment with that, and pass it down:

Note that, crucially, we use env', and not just env, when analyzing the right-hand sides. It has to be that way, as all the variables are in scope in all the right-hand sides.

In a strict language, such a mutually recursive definition, where env_bind uses env' which uses env_bind is basically unthinkable. But in a lazy language like Haskell, it might just work.

Unfortunately, it works only as long as the recursive bindings are not actually recursive, or if they are recursive, they are not used:

ghci> canThrow1 $ LetRec [("x", Throw)] (Var "x")
True
ghci> canThrow1 $ LetRec [("x", App (Var "y") someVal), ("y", Throw)] (Var "x")
True
ghci> canThrow1 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "y")
True

But with genuine recursion, it does not work, and simply goes into a recursive cycle:

ghci> canThrow1 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "x")
^CInterrupted.

That is disappointing! Do we really have to toss that code and somehow do an explicit fixed-point calculation here? Obscuring our nice declarative code? And possibly having to repeat work (such as traversing the syntax tree) many times that we should only have to do once?

rec-def to the rescue

Not with rec-def! Using RBool from Data.Recursive.Bool instead of Bool, we can write the exact same code, as follows:

And it works!

ghci> canThrow2 $ LetRec [("x", App (Var "x") someVal), ("y", Throw)] (Var "x")
False
ghci> canThrow2 $ LetRec [("x", App (Var "x") Throw), ("y", Throw)] (Var "x")
True

I find this much more pleasing than the explicit naive fix-pointing you might do otherwise, where you stabilize the result at each LetRec independently: Not only is all that extra work hidden from the programmer, but now also a single traversal of the syntax tree creates, thanks to the laziness, a graph of RBool values, which are then solved “under the hood”.

The issue with x=x

There is one downside worth mentioning: canThrow2 fails to produce a result in case we hit x=x:

ghci> canThrow2 $ LetRec [("x", Var "x")] (Var "x")
^CInterrupted.

This is, after all the syntax tree has been processed and all the map lookups have been resolved, equivalent to

ghci> let x = x in RB.get (x :: RBool)
^CInterrupted.

which also does not work. The rec-def machinery can only kick in if at least one of its function is used on any such cycle, even if it is just a form of identity (which I ~ought to add to the library~ since have added to the library):

ghci> idR x = RB.false ||| x
ghci> let x = idR x in getR (x :: R Bool)
False

And indeed, if I insert a call to idR in the line

then our analyzer will no longer stumble over these nasty recursive equations:

ghci> canThrow2 $ LetRec [("x", Var "x")] (Var "x")
False

It is a bit disappointing to have to do that, but I do not see a better way yet. I guess the def-rec library expects the programmer to have a similar level of sophistication as other tie-the-know tricks with laziness (where you also have to ensure that your definitions are productive and that the sharing is not accidentally lost).

14 September, 2022 09:53PM by Joachim Breitner (mail@joachim-breitner.de)

Russell Coker

Storing Local Secrets

In the operation of a normal Linux system there are many secrets stored on behalf of a user. Wifi passwords, passwords from web sites, etc. Ideally you want them to be quickly and conveniently accessible to the rightful user but also be as difficult as possible for hostile parties to access.

The solution in GNOME and KDE is to have a wallet that is encrypted to store such passwords, the idea is that if a hostile party gets access to a PC that doesn’t use full disk encryption then the secrets will be protected. This is an OK feature. In early versions it required entering a password every time you logged in. The current default mode of operation is to have the login password used to decrypt the wallet which is very convenient.

The problem is the case where the user login password has a scope larger than the local PC, EG a domain login password for Active Directory, Kerberos, or similar systems. In such a case if an attacker gets the encrypted wallet that could facilitate a brute force attack on the password used for domain logins.

I think that a better option for this would be to store wallets in a directory that the user can’t access directly, EG a mode 1770 directory with group “wallet”. Then when logging in a PAM process running as root could open the wallet and pass a file handle to a process running in the context of the user. For access apart from login there could be SETGID programs to manage it which could require authenticating the user’s password before any operation that exports the data so that a vulnerability in a web browser or other Internet facing program can’t just grab the file contents.

Storing the data in a file that needs a SETGID or root owned process to access it doesn’t preclude the possibility of encrypting that file. The same encryption options would be available including encrypting with the login password and unlocking at login time via PAM. The difference is that a brute force attack to discover the login password would first require breaking the security of one of those SETGID programs to get access to the raw data – direct attacks by running the wallet open command repeatedly could be managed by the usual rate limiting mechanisms and logging in the system logs.

The same methods could be used for protecting the secret keys for GPG and SSH which by default are readable by all processes running in the user context and encrypted with a passphrase.

The next issue to consider is where to store such an restricted directory for wallets. Under the user home directory would give the advantage of having the same secrets operate over a network filesystem and not need anything special in backup configuration. Under /var/lib would give the advantage of better isolation from all the less secret (in a cryptographic sense) data in the user home directories.

What do you think?

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14 September, 2022 01:01AM by etbe

September 13, 2022

Alberto García

Adding software to the Steam Deck with systemd-sysext

Yakuake on SteamOS

Introduction: an immutable OS

The Steam Deck runs SteamOS, a single-user operating system based on Arch Linux. Although derived from a standard package-based distro, the OS in the Steam Deck is immutable and system updates replace the contents of the root filesystem atomically instead of using the package manager.

An immutable OS makes the system more stable and its updates less error-prone, but users cannot install additional packages to add more software. This is not a problem for most users since they are only going to run Steam and its games (which are stored in the home partition). Nevertheless, the OS also has a desktop mode which provides a standard Linux desktop experience, and here it makes sense to be able to install more software.

How to do that though? It is possible for the user to become root, make the root filesytem read-write and install additional software there, but any changes will be gone after the next OS update. Modifying the rootfs can also be dangerous if the user is not careful.

Ways to add additional software

The simplest and safest way to install additional software is with Flatpak, and that’s the method recommended in the Steam Deck Desktop FAQ. Flatpak is already installed and integrated in the system via the Discover app so I won’t go into more details here.

However, while Flatpak works great for desktop applications not every piece of software is currently available, and Flatpak is also not designed for other types of programs like system services or command-line tools.

Fortunately there are several ways to add software to the Steam Deck without touching the root filesystem, each one with different pros and cons. I will probably talk about some of them in the future, but in this post I’m going to focus on one that is already available in the system: systemd-sysext.

About systemd-sysext

This is a tool included in recent versions of systemd and it is designed to add additional files (in the form of system extensions) to an otherwise immutable root filesystem. Each one of these extensions contains a set of files. When extensions are enabled (aka “merged”) those files will appear on the root filesystem using overlayfs. From then on the user can open and run them normally as if they had been installed with a package manager. Merged extensions are seamlessly integrated with the rest of the OS.

Since extensions are just collections of files they can be used to add new applications but also other things like system services, development tools, language packs, etc.

Creating an extension: yakuake

I’m using yakuake as an example for this tutorial since the extension is very easy to create, it is an application that some users are demanding and is not easy to distribute with Flatpak.

So let’s create a yakuake extension. Here are the steps:

1) Create a directory and unpack the files there:

$ mkdir yakuake
$ wget https://steamdeck-packages.steamos.cloud/archlinux-mirror/extra/os/x86_64/yakuake-21.12.1-1-x86_64.pkg.tar.zst
$ tar -C yakuake -xaf yakuake-*.tar.zst usr

2) Create a file called extension-release.NAME under usr/lib/extension-release.d with the fields ID and VERSION_ID taken from the Steam Deck’s /etc/os-release file.

$ mkdir -p yakuake/usr/lib/extension-release.d/
$ echo ID=steamos > yakuake/usr/lib/extension-release.d/extension-release.yakuake
$ echo VERSION_ID=3.3.1 >> yakuake/usr/lib/extension-release.d/extension-release.yakuake

3) Create an image file with the contents of the extension:

$ mksquashfs yakuake yakuake.raw

That’s it! The extension is ready.

A couple of important things: image files must have the .raw suffix and, despite the name, they can contain any filesystem that the OS can mount. In this example I used SquashFS but other alternatives like EroFS or ext4 are equally valid.

NOTE: systemd-sysext can also use extensions from plain directories (i.e skipping the mksquashfs part). Unfortunately we cannot use them in our case because overlayfs does not work with the casefold feature that is enabled on the Steam Deck.

Using the extension

Once the extension is created you simply need to copy it to a place where systemd-systext can find it. There are several places where they can be installed (see the manual for a list) but due to the Deck’s partition layout and the potentially large size of some extensions it probably makes more sense to store them in the home partition and create a link from one of the supported locations (/var/lib/extensions in this example):

(deck@steamdeck ~)$ mkdir extensions
(deck@steamdeck ~)$ scp user@host:/path/to/yakuake.raw extensions/
(deck@steamdeck ~)$ sudo ln -s $PWD/extensions /var/lib/extensions

Once the extension is installed in that directory you only need to enable and start systemd-sysext:

(deck@steamdeck ~)$ sudo systemctl enable systemd-sysext
(deck@steamdeck ~)$ sudo systemctl start systemd-sysext

After this, if everything went fine you should be able to see (and run) /usr/bin/yakuake. The files should remain there from now on, also if you reboot the device. You can see what extensions are enabled with this command:

$ systemd-sysext status
HIERARCHY EXTENSIONS SINCE
/opt      none       -
/usr      yakuake    Tue 2022-09-13 18:21:53 CEST

If you add or remove extensions from the directory then a simple “systemd-sysext refresh” is enough to apply the changes.

Unfortunately, and unlike distro packages, extensions don’t have any kind of post-installation hooks or triggers, so in the case of Yakuake you probably won’t see an entry in the KDE application menu immediately after enabling the extension. You can solve that by running kbuildsycoca5 once from the command line.

Limitations and caveats

Using systemd extensions is generally very easy but there are some things that you need to take into account:

  1. Using extensions is easy (you put them in the directory and voilà!). However, creating extensions is not necessarily always easy. To begin with, any libraries, files, etc., that your extensions may need should be either present in the root filesystem or provided by the extension itself. You may need to combine files from different sources or packages into a single extension, or compile them yourself.
  2. In particular, if the extension contains binaries they should probably come from the Steam Deck repository or they should be built to work with those packages. If you need to build your own binaries then having a SteamOS virtual machine can be handy. There you can install all development files and also test that everything works as expected. One could also create a Steam Deck SDK extension with all the necessary files to develop directly on the Deck 🙂
  3. Extensions are not distribution packages, they don’t have dependency information and therefore they should be self-contained. They also lack triggers and other features available in packages. For desktop applications I still recommend using a system like Flatpak when possible.
  4. Extensions are tied to a particular version of the OS and, as explained above, the ID and VERSION_ID of each extension must match the values from /etc/os-release. If the fields don’t match then the extension will be ignored. This is to be expected because there’s no guarantee that a particular extension is going to work with a different version of the OS. This can happen after a system update. In the best case one simply needs to update the extension’s VERSION_ID, but in some cases it might be necessary to create the extension again with different/updated files.
  5. Extensions only install files in /usr and /opt. Any other file in the image will be ignored. This can be a problem if a particular piece of software needs files in other directories.
  6. When extensions are enabled the /usr and /opt directories become read-only because they are now part of an overlayfs. They will remain read-only even if you run steamos-readonly disable !!. If you really want to make the rootfs read-write you need to disable the extensions (systemd-sysext unmerge) first.
  7. Unlike Flatpak or Podman (including toolbox / distrobox), this is (by design) not meant to isolate the contents of the extension from the rest of the system, so you should be careful with what you’re installing. On the other hand, this lack of isolation makes systemd-sysext better suited to some use cases than those container-based systems.

Conclusion

systemd extensions are an easy way to add software (or data files) to the immutable OS of the Steam Deck in a way that is seamlessly integrated with the rest of the system. Creating them can be more or less easy depending on the case, but using them is extremely simple. Extensions are not packages, and systemd-sysext is not a package manager or a general-purpose tool to solve all problems, but if you are aware of its limitations it can be a practical tool. It is also possible to share extensions with other users, but here the usual warning against installing binaries from untrusted sources applies. Use with caution, and enjoy!

13 September, 2022 06:00PM by berto

September 12, 2022

Petter Reinholdtsen

Time to translate the Bullseye edition of the Debian Administrator's Handbook

(The picture is of the previous edition.)

Almost two years after the previous Norwegian Bokmål translation of the "The Debian Administrator's Handbook" was published, a new edition is finally being prepared. The english text is updated, and it is time to start working on the translations. Around 37 percent of the strings have been updated, one way or another, and the translations starting from a complete Debian Buster edition now need to bring their translation up from 63% to 100%. The complete book is licensed using a Creative Commons license, and has been published in several languages over the years. The translations are done by volunteers to bring Linux in their native tongue. The last time I checked, it complete text was available in English, Norwegian Bokmål, German, Indonesian, Brazil Portuguese and Spanish. In addition, work has been started for Arabic (Morocco), Catalan, Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish, Dutch, French, Greek, Italian, Japanese, Korean, Persian, Polish, Romanian, Russian, Swedish, Turkish and Vietnamese.

The translation is conducted on the hosted weblate project page. Prospective translators are recommeded to subscribe to the translators mailing list and should also check out the instructions for contributors.

I am one of the Norwegian Bokmål translators of this book, and we have just started. Your contribution is most welcome.

As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b.

12 September, 2022 01:45PM

September 11, 2022

hackergotchi for Dirk Eddelbuettel

Dirk Eddelbuettel

RcppArmadillo 0.11.2.4.0 on CRAN: Bugfix and Deprecation

armadillo image

Armadillo is a powerful and expressive C++ template library for linear algebra and scientific computing. It aims towards a good balance between speed and ease of use, has a syntax deliberately close to Matlab, and is useful for algorithm development directly in C++, or quick conversion of research code into production environments. RcppArmadillo integrates this library with the R environment and language–and is widely used by (currently) 1016 packages other packages on CRAN, downloaded 26.2 million times (per the partial logs from the cloud mirrors of CRAN), and the CSDA paper (preprint / vignette) by Conrad and myself has been cited 493 times according to Google Scholar.

This new release (made yesterday) brings three changes. First, it updates the release to the upstream 11.2.4 bugfix release made days ago by Conrad. Second, it contains support for the deprecation transition we are managing in issue #391. In short, the (convenient but non-standard) initialization via use of << has been deprecated upstream. Until all packages are updated, we override this in the RcppArmadillo but aim to become ‘compliant’. Out of the over 1000 packages, a mere 25 need small adjustments. I reached out email and PRs, and the response has been great. Eight packages are already updated on CRAN, and several others have already in integrated or merged the change. Lastly, Conrad pointed out that the fastLm() example and application can be written more concisely by using arma::dot().

The full set of changes (since the last CRAN release 0.11.2.3.1) follows.

Changes in RcppArmadillo version 0.11.2.4.0 (2022-09-09)

  • Upgraded to Armadillo release 11.2.4 (Classic Roast)

    • fix handling of std::move() involving matrices constructed with auxiliary memory

  • In the fastLm() examples, use arma::dot() to compute to the inner product (as proposed by Conrad), plus small edits

  • Support optional #define named RCPPARMADILLO_FORCE_DEPRECATE to suppress use of ARMA_IGNORE_DEPRECATED_MARKER permitting use and development under deprecation

Courtesy of my CRANberries, there is a diffstat report relative to previous release. More detailed information is on the RcppArmadillo page. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page.

If you like this or other open-source work I do, you can sponsor me at GitHub.

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

11 September, 2022 08:31PM

hackergotchi for Shirish Agarwal

Shirish Agarwal

Politics, accessibility, books

Politics

I have been reading books, both fiction and non-fiction for a long long time. My first book was a comic most probably when I was down with Malaria when I was a kid. I must be around 4-5 years old. Over the years, books have given me great joy and I continue to find nuggets of useful information, both in fiction as well as non-fiction books. So here’s to sharing something and how that can lead you to a rabbit hole. This entry would be a bit NSFW as far as language is concerned.

NYPD Red 5 by James Patterson – First of all, have no clue as to why James Patterson’s popularity has been falling. He used to be right there with Lee Child and others, but not so much now. While I try to be mysterious about books, I would give a bit of heads-up so people know what to expect. This is probably more towards the Adult crowd as there is a bit of sex as well as quite a few grey characters. The NYPD Red is a sort of elite police task force that basically is for celebrities. In the book series, they do a lot of ass-kissing (figuratively more than literally).

Now the reason I have always liked fiction is that however wild the assumption or presumption is, it does have somewhere a grain of truth. And each and every time I read a book or two, that gets cemented. One of the statements in the book told something about how 9/11 took a lot of police personnel out of the game. First, there were a number of policemen who were patrolling the Two Towers, so they perished literally during the explosion. Then there were policemen who were given the cases to close the cases (bring the cases to conclusion). When you are investigating your own brethren or even civilians who perished 9/11 they must have experienced emotional trauma and no outlet. Mental health even in cops is the same and given similar help as you and me (i.e. next to none.) But both of these were my assumptions. The only statement that was in the book was they lost a lot of bench strength. Even NYFD (New York Fire Department). This led me to me to With Crime At Record Lows, Should NYC Have Fewer Cops? This is more right-wing sentiment and in fact, there have been calls to defund the police. This led me to https://cbcny.org/ and one specific graph. Unfortunately, this tells the story from 2010-2022 but not before. I was looking for data from around 1999 to 2005 because that will tell whether or not it happened.

Then I remembered reading in newspapers the year or two later how 9/11 had led NYC to recession. I looked up online and for sure NY was booming before 9/11. One can argue that NYC could come down and that is pretty much possible, everything that goes up comes down, it’s a law of nature but it would have been steady rather than abrupt. And once you are in recession, the first thing to go is personnel. So people both from NYPD and NYFD were let go, even though they were needed the most then. As you can see, a single statement in a book can take you to places & time literally.

Edit: Addition 11th September – There were quite a few people who also died from New York Port Authority and they also lost quite a number of people directly and indirectly and did a lot of patrolling of the water bodies near NYC. Later on, even in their department, there were a lot of early retirements.

Kosovo

A couple of days back I had a look at the Debconf 2023 BOF that was done in Kosovo. One of the interesting things that happened during the BOF is when a woman participant chimed in and asks India to recognize Kosovo. Immediately it triggered me and I opened the Kosovo Wikipedia page to get some understanding of the topic. Reading up on it, came to know Russia didn’t agree and doesn’t recognize Kosovo. Mr. Modi likes Putin and India imports a lot of its oil from Russia. Unrelatedly, but still useful, we rejected to join IPEF. Earlier, we had rejected China’s BRI. India has never been as vulnerable as she is now. Our foreign balance has reached record lows. Now India has been importing quite a bit of Russian crude and has been buying arms and ammunition from them. We are also scheduled to buy a couple of warships and submarines etc. We even took arms and ammunition from them on lease. So we can’t afford that they are displeased with India. Even though Russia has more than friendly relations with both China and Pakistan. At the same time, the U.S. is back to aiding Pakistan which the mainstream media in India refuses to even cover. And to top all of this, we have the Chip 4 Alliance but that needs its own article, truth be told but we will do with a paragraph 😦

Edit – Addition 11th September – Seems Kosovo isn’t unique in that situation, there are 3-4 states like that. A brief look at worldpopulationreview tells you there are many more.

Chip 4 Alliance

For almost a decade I have been screaming about this on my blog as well as everywhere that chip fabrication is a national security thing. And for years, most people deny it. And now we have chip 4 alliance. Now to understand this, you have to understand that China for almost a decade, somewhere around 2014 or so came up with something called ‘the big fund‘. Now one can argue one way or the other how successful the fund has been, but it has, without doubt, created ripples so strong that the U.S., Taiwan, Japan, and probably South Korea will join and try to stem the tide. Interestingly, in this grouping, South Korea is the weakest in the statements and what they have been saying. Within the group itself, there is a lot of tension and China would use that and there are a number of unresolved issues between the three countries that both China & Russia would exploit. For e.g. the Comfort women between South Korea and Japan. Or the 1985 Accord Agreement between Japan and the U.S.

Now people need to understand this, this is not just about China but also about us. If China has 5-6x times India’s GDP and their research budget is at the very least 100x times what India spends, how do you think we will be self-reliant? Whom are we fooling? Are we not tired of fooling ourselves 😦 In diplomacy, countries use leverage. Sadly, we let go of some of our most experienced negotiators in 2014 and since then have been singing in the wind 😦

Accessibility, Jitsi, IRC, Element-Desktop

The Wikipedia page on Accessibility says the following – Accessibility is the design of products, devices, services, vehicles, or environments so as to be usable by people with disabilities. The concept of accessible design and practice of accessible development ensures both “direct access” (i.e. unassisted) and “indirect access” meaning compatibility with a person’s assistive technology. Now IRC or Internet Relay Chat has been accessible for a long time. I know of even blind people who have been able to navigate IRC quite effortlessly as there has been a lot of work done to make sure all the joints ‘speak to each other’ so people with one or more disabilities still can use, and contribute without an issue. It does help that IRC and many clients have been there since the 1970s so most of them have had more than enough time to get all the bugs fixed and both text-to-speech and speech-to-text work brilliantly on IRC. Newer software like Jitsi or for that matter Telegram is lacking those features. A few days ago, discovered on Telegram I was shared that Samsung Voice input is also able to do the same. The Samsung Voice Input works wonder as it translates voice to text, I have not yet tried the text-to-speech but perhaps somebody can and they can share whatever the results can be one way or the other. I have tried element-desktop both on the desktop as well as mobile phone and it has been disappointing, to say the least. On the desktop, it is unruly and freezes once in a while, and is buggy. The mobile version is a little better but that’s not saying a lot. I prefer the desktop version as I can use the full-size keyboard. The bug I reported has been there since its Riot days. I had put up a bug report even then. All in all, yesterday was disappointing 😦

11 September, 2022 03:47AM by shirishag75

Russ Allbery

Review: Hogfather

Review: Hogfather, by Terry Pratchett

Series: Discworld #20
Publisher: Harper
Copyright: 1996
Printing: February 2014
ISBN: 0-06-227628-X
Format: Mass market
Pages: 402

Hogfather is the 20th Discworld novel and not a very good place to start. I recommend at least reading Soul Music first for a proper introduction to Susan, and you may want to start with Mort.

When we last saw Susan, she was a student at the Quirm College for Young Ladies. Now she's a governess for two adorable youngsters, a job that includes telling them stories and dealing quite capably with monsters in the cellar. (She uses a poker.) It also includes answering questions like whether the Hogfather really exists or whether the presents just come from your parents.

"Look at it this way, then," she said, and took a deep mental breath. "Wherever people are obtuse and absurd... and wherever they have, by even the most generous standards, the attention span of a small chicken in a hurricane and the investigative ability of a one-legged cockroach... and wherever people are inanely credulous, pathetically attached to the certainties of the nursery and, in general, have as much grasp of the physical universe as an oyster has of mountaineering... yes, Twyla: there is a Hogfather.

Meanwhile, the Auditors, last seen meddling with Death in Reaper Man, approach the Assassin's Guild in Ankh-Morpork to hire the assassination of the Hogfather. This rather unusual assignment falls to Mister Teatime, an orphan who was taken in by the guild at an early age and trained to be an assassin. Teatime is a little unnerving, mostly because he enjoys being an assassin. Rather a lot.

Hogfather has two major things to recommend it: it's a Death novel, and it features Susan, who is one of my favorite Discworld characters. It also has two major strikes against it, at least for me.

The first is relatively minor but, for me, the most irritating. A bit of the way into the story, Pratchett introduces the Oh God of Hangovers — fair, that's a good pun — and then decides that's a good excuse for nausea and vomiting jokes. A lot of nausea and vomiting jokes.

Look. I know a lot of people don't mind this. But I beg authors (and, even more so, filmmakers and cartoonists) to consider whether a joke that some of your audience might like is worth making other parts of your audience feel physically ill while trying to enjoy your work. It's not at all a pleasant experience, and while I handle it better in written form, it still knocks me out of the story and makes me want to skip over scenes with the obnoxious character who won't shut up about it. Thankfully this does stop by the end of the book, but there are several segments in the middle that were rather unpleasant.

The second is that Pratchett tries to convince the reader of the mythical importance of the Santa Claus myth (for which Hogfather is an obvious stand-in, if with a Discworld twist), an effort for which I am a highly unsympathetic audience. I'm with Susan above, with an extra helping of deep dislike for telling children who trust you something that's literally untrue. Pratchett does try: he has Death makes a memorable and frequently-quoted point near the end of the book (transcribed below) that I don't entirely agree with but still respect. But still, the book is very invested in convincing Susan that people believing mythology is critically important to humanity, and I have so many problems with the literalness of "believing" and the use of trusting children for this purpose by adults who know better.

There are few topics that bring out my grumpiness more than Santa Claus.

Grumbling aside, though, I did enjoy this book anyway. Susan is always a delight, and I could read about her adventures as a governess for as long as Pratchett wanted to write them. Death is filling in for the Hogfather for most of the book, which is hilarious because he's far too good at it, in his painfully earnest and literal way, to be entirely safe. I was less fond of Albert's supporting role (who I am increasingly coming to dislike as a character), but the entire scene of Death as a mall Santa is brilliant. And Teatime is an effective, creepy villain, something that the Discworld series doesn't always deliver. The powers arrayed on Discworld are so strong that it can be hard to design a villain who effectively challenges them, but Teatime has a sociopathic Professor Moriarty energy with added creepiness that fills that role in this book satisfyingly.

As is typical for Pratchett (at least for me), the plot was serviceable but not the highlight. Pratchett plays in some interesting ways with a child's view of the world, the Unseen University bumbles around as a side plot, and it comes together at the end in a way that makes sense, but the journey is the fun of the story. The conclusion felt a bit gratuitous, there mostly to wrap up the story than something that followed naturally from the previous plot. But it does feature one of the most quoted bits in Discworld:

"All right," said Susan. "I'm not stupid. You're saying humans need... fantasies to make life bearable."

REALLY? AS IF IT WAS SOME KIND OF PINK PILL? NO. HUMANS NEED FANTASY TO BE HUMAN. TO BE THE PLACE WHERE THE FALLING ANGEL MEETS THE RISING APE.

"Tooth fairies? Hogfathers? Little—"

YES. AS PRACTICE. YOU HAVE TO START OUT LEARNING TO BELIEVE THE LITTLE LIES.

"So we can believe the big ones?"

YES. JUSTICE. MERCY. DUTY. THAT SORT OF THING.

"They're not the same at all!"

YOU THINK SO? THEN TAKE THE UNIVERSE AND GRIND IT DOWN TO THE FINEST POWDER AND SIEVE IT THROUGH THE FINEST SIEVE AND THEN SHOW ME ONE ATOM OF JUSTICE, ONE MOLECULE OF MERCY. AND YET — Death waved a hand. AND YET YOU ACT AS IF THERE IS SOME IDEAL ORDER IN THE WORLD, AS IF THERE IS SOME...SOME RIGHTNESS IN THE UNIVERSE BY WHICH IT MAY BE JUDGED.

"Yes, but people have got to believe that, or what's the point—"

MY POINT EXACTLY.

Here's the thing, though: Susan is right. They're not the same sort of thing at all, and Pratchett doesn't present an argument that they are. Death's response is great, but it's also a non sequitur: it is true and correct but has nothing to do with Susan's argument. Justice is not a lie in the sense that Santa Claus is a lie: justice is something that humans can create, just like humans can create gift-giving or a tradition of imaginative story-telling. But this is not at all the same thing as encouraging children to believe in the literal existence of a fat man in red who comes down chimneys to deliver gifts by magic.

And Death isn't even correct in Discworld! If one pays careful attention to the story, the consequences he's thinks would follow from the Auditors' attempt on the Hogfather not only don't happen, the exact opposite happens. This is the point of the Unseen University subplot, and it's also what happened in Reaper Man. The Auditors may be trying to kill mythology, but what the books show is that the real danger comes from the backlash. The force they're meddling with is far more powerful and persistent than they are.

Death appears to be, by the stated events of the story, completely incorrect in his analysis of Discworld's metaphysics. Maybe Pratchett knows this? He did write a story that contradicts Death's analysis if one reads it carefully. But if so, this is not obvious from the text, or from Susan's reaction to Death's speech, which makes the metaphysics weirdly unsatisfying.

So, overall, a mixed bag. Most of the book is very fun, but the metaphysics heavily rest on a pet peeve of mine, and I really could have done without the loving descriptions of the effects of hangovers. This is one of the more famous Discworld novels for the above quote, and on its own this is deserved (it's a great quote), but I think the logic is muddled and the story itself contradicts the implications. A rather odd reading experience.

Followed by Jingo in publication order, and Thief of Time thematically.

Rating: 7 out of 10

11 September, 2022 02:06AM

Andrew Cater

202209110020 - Debian release day(s) - Cambridge - post 4

 RattusRattus, Isy, smcv have all just left after a very long day. Steve is finishing up the final stages. The mayhem has quietened, the network cables are coiled, pretty much everything is tidied away. A new experience for two of us - I just hope it hasn't put them off too much.

The IRC channels are quiet and we can put this one to bed after a good day's work well done.

11 September, 2022 12:24AM by Andrew Cater (noreply@blogger.com)

September 10, 2022

202209102213 - Debian release day - Cambridge - post 3

Working a bit more slowly - coming to the end of the process. I've been wrestling with a couple of annoying old laptops and creating mayhem. The others are almost through the process - it's been a very long day, almost 12 hours now.

As ever, it's good to be with people who appreciate this work - I'm also being menaced by a dog that wants fuss all the time. It certainly makes a difference to have fast connectivity and even faster remarks backwards and forwards.



10 September, 2022 10:18PM by Andrew Cater (noreply@blogger.com)

202209101602 Debian release day - Cambridge - post 2

Definitely settling into a rhythm - we've been joined by smcv in person (and bittin on line). Bullseye testing is now well beyond the standard image testing into the live images.

Buster images are gradually being built so there's the added confusion of two sets of wiki editing, two sets of potential edit conflicts ...

So six people in a small-ish sitting room, several with multiple laptops running several checks at once. It's all good, as ever.

Dining room table has nine machines on it, three packet switches are fairly well full ...

10 September, 2022 04:14PM by Andrew Cater (noreply@blogger.com)

202209101115 Debian release day - Cambridge - Bullseye and Buster testing starting

And I'm over here with the Debian images/media release team in Cambridge.

First time together in Cambridge for a long time: several of the usual suspects - RattusRattus, Sledge, Isy and myself. Also in the room are Kartik and egw - I think this is their first time.

Chat is now physically in Sledge's sitting room as well as on IRC. The first couple of images are trickling in and tests are starting for Bullseye.

This is going to be a very long day - we've got full tests for Bullseye (Debian 11) and Buster (Debian 10) so double duty. This should be the last release for Buster since this has now passed to LTS.

10 September, 2022 11:21AM by Andrew Cater (noreply@blogger.com)

hackergotchi for Holger Levsen

Holger Levsen

20220910-youngest-LUKS-user

youngest LUKS user I know...

So I'm in Berlin currently to attend the fourth Qubes OS Summit, also to discuss the future of the reproducible-builds.org mirror of snapshot.debian.org and in the evening I've met an old Debian friend who told a lovely story about his 5 year old daughter, who since recently is a Debian user using an old laptop with LUKS encryption, knowing her data will be lost when she forgets her passphrase... 😀

The Qubes OS Summit is also very cool, great people and exciting developments!

10 September, 2022 10:39AM

hackergotchi for Junichi Uekawa

Junichi Uekawa

Tried implementing FUSE cpiofs.

Tried implementing FUSE cpiofs. I thought it might be fun to implement a file system that can mount initrd file systems. I've implemented symlinks and regular files handling and then I realized that it is kind of annoying that I need to implement hard links. cpiofs

10 September, 2022 09:53AM by Junichi Uekawa

hackergotchi for Joachim Breitner

Joachim Breitner

rec-def: Behind the scenes

A week ago I wrote about the rec-def Haskell library, which allows you to write more recursive definitions, such as in this small example:

let s1 = RS.insert 23 s2
    s2 = RS.insert 42 s1
in RS.get s1

This will not loop (as it would if you’d just used Data.Set), but rather correctly return the set S.fromList [23,42]. See the previous blog post for more examples and discussion of the user-facing side of this.

For quick reference, these are the types of the functions involved here:

The type of s1 and s2 above is not Set Int, but rather RSet Int, and in this post I’ll explain how RSet works internally.

Propagators, in general

The conceptual model behind an recursive equation like above is

  • There are a multiple cells that can hold values of an underlying type (here Set)
  • These cells have relations that explain how the values in the cells should relate to each other
  • After registering all the relations, some form of solving happens.
  • If the solving succeeds, we can read off the values from the cells, and they should satisfy the registered relation.

This is sometimes called a propagator network, and is a quite general model that can support different kind of relations (e.g. equalities, inequalities, functions), there can be various solving strategies (iterative fixed-points, algebraic solution, unification, etc.) and information can flow on along the edges (and hyper-edges) possibly in multiple directions.

For our purposes, we only care about propagator networks where all relations are functional, so they have a single output cell that is declared to be a function of multiple (possibly zero) input cells, without affecting these input cells. Furthermore, every cell is the output of exactly one such relation.

IO-infested propagator interfaces

This suggests that an implementation of such a propagator network could provide an interface with the following three operations:

  • Functions to declare cells
  • Functions to declare relations
  • Functions to read values off cells

This is clearly an imperative interface, so we’ll see monads, and we’ll simply use IO. So concretely for our small example above, we might expect

There is no need for an explicit “solve” function: solving can happen when declareInsert or getCell is called – as a User I do not care about that.

You might be curious about the implementation of newCell, declareInsert and getCell, but I have to disappoint you: This is not the topic of this article. Instead, I want to discuss how to turn this IO-infested interface into the pure interface seen above?

Pure, but too strict

Obviously, we have to get rid of the IO somehow, and have to use unsafePerformIO :: IO a -> a somehow. This dangerous function creates a pure-looking value that, when used the first time, will run the IO-action and turn into that action’s result.

So maybe we can simply write the following:

Indeed, the types line up, but if we try to use that code, nothing will happen. Our insert is too strict to be used recursively: It requires the value of c2 (as it is passed to declareInsert, which we assume to be strict in its arguments) before it can return c1, so the recursive example at the top of this post will not make any progress.

Pure, lazy, but forgetful

To work around this, maybe it suffices if we do not run declareInsert right away, but just remember that we have to do it eventually? So let’s introduce a new data type for RSet a that contains not just the cell (Cell a), but also an action that we still have to run before getting a value:

This is better: insert is now lazy in its arguments (for this it is crucial to pattern-match on RSet only inside the todo code, not in the pattern of insert!) This means that our recursive code above does not get stuck right away.

Pure, lazy, but runs in circles

But it is still pretty bad: Note that we do not run get s2 in the example above, so that cell’s todo, which would declareInsert 42, will never run. This cannot work! We have to (eventually) run the declaration code from all involved cells before we can use getCell!

We can try to run the todo action of all the dependencies as part of a cell’s todo action:

Now we certainly won’t forget to run the second cell’s todo action, so that is good. But that cell’s todo action will run the first cell’s todo action, and that again the second cell’s, and so on.

Pure, lazy, terminating, but not thread safe

This is silly: We only need (and should!) run that code once! So let’s keep track of whether we ran it already:

Ah, much better: It works! Our call to get c1 will trigger the first cell’s todo action, which will mark it as done before calling the second cell’s todo action. When that now invokes the first cell’s todo action, it is already marked done and we break the cycle, and by the time we reach getCell, all relations have been correctly registered.

In a single-threaded world, this would be all good and fine, but we have to worry about multiple threads running get concurrently, on the same or on different cells.

In fact, because we use unsafePerformIO, we have to worry about this even when the program is not using threads.

And the above code has problems. Imagine a second call to get c1 while the first one has already marked it as done, but has not finished processing all the dependencies yet: It will call getCell before all relations are registered, which is bad.

Recursive do-once IO actions

Making this thread-safe seems to be possible, but would clutter both the code and this blog post. So let’s hide that problem behind a nice and clean interface. Maybe there will be a separate blog post about its implementation (let me know if you are curious), or you can inspect the code in System.IO.RecThunk module yourself). The interface is simply

data Thunk
thunk :: IO [Thunk] -> IO Thunk
force :: Thunk -> IO ()

and the idea is that thunk act will defer the action act until the thunk is passed to force for the first time, and force will not return until the action has been performed (possibly waiting if another thread is doing that at the moment), and also until the actions of all the thunks returned by act have performed, recursively, without running into cycles.

We can use this in our definition of RSet and get to the final, working solution:

This snippet captures the essential ideas behind rec-def:

  • Use laziness to allow recursive definition to describe the propagator graph naturally
  • Use a form of “explicit thunk” to register the propagator graph relations at the right time (not too early/strict, not too late)

And that’s all?

The actual implementation in rec-def has a few more moving parts.

In particular, it tries to support different value types (not just sets), possibly with different implementations, and even mixing them (e.g. in member :: Ord a => a -> RSet a -> RBool), so the generic code is in Data.Propagator.Purify, and supports various propagators underneath. The type RSet is then just a newtype around that, defined in Data.Recursive.Internal to maintain the safety of the abstraction,

I went back and forth on a few variants of the design here, including one where there was a generic R type constructor (R (Set a), R Bool etc.), but then monomorphic interface seems simpler.

Does it really work?

The big remaining question is certainly: Is this really safe and pure? Does it still behave like Haskell?

The answer to these questions certainly depends on the underlying propagator implementation. But it also depends on what we actually mean by “safe and pure”? For example, do we expect the Static Argument Transformation be semantics preserving? Or is it allowed to turn undefined values into defined ones (as it does here)?

I am unsure myself yet, so I’ll defer this discussion to a separate blog post, after I hopefully had good discussions about this here at ICFP 2022 in Ljubljana. If you are around and want to discuss, please hit me up!

10 September, 2022 09:08AM by Joachim Breitner (mail@joachim-breitner.de)

September 09, 2022

Reproducible Builds

Reproducible Builds in August 2022

Welcome to the August 2022 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. The motivation behind the reproducible builds effort is to ensure no flaws have been introduced during this compilation process by promising identical results are always generated from a given source, thus allowing multiple third-parties to come to a consensus on whether a build was compromised.

As ever, if you are interested in contributing to the project, please visit our Contribute page on our website.

Community news

As announced last month, registration is currently open for our in-person summit this year which is due to be held between November 1st → November 3rd. The event will take place in Venice (Italy). Very soon we intend to pick a venue reachable via the train station and an international airport. However, the precise venue will depend on the number of attendees. Please see the announcement email for information about how to register.

The US National Security Agency (NSA), Cybersecurity and Infrastructure Security Agency (CISA) and the Office of the Director of National Intelligence (ODNI) have released a document called “Securing the Software Supply Chain: Recommended Practices Guide for Developers” (PDF) as part of their Enduring Security Framework (ESF) work.

The document expressly recommends having reproducible builds as part of “advanced” recommended mitigations, along with hermetic builds. Page 31 (page 35 in the PDF) says:

Reproducible builds provide additional protection and validation against attempts to compromise build systems. They ensure the binary products of each build system match: i.e., they are built from the same source, regardless of variable metadata such as the order of input files, timestamps, locales, and paths. Reproducible builds are those where re-running the build steps with identical input artifacts results in bit-for-bit identical output. Builds that cannot meet this must provide a justification why the build cannot be made reproducible.

The full press release is available online.

On our mailing list this month, Marc Prud’hommeaux posted a feature request for diffoscope which additionally outlines a project called The App Fair, an autonomous distribution network of free and open-source macOS and iOS applications, where “validated apps are then signed and submitted for publication”.

Author/blogger Cory Doctorow posted published a provocative blog post this month titled “Your computer is tormented by a wicked god”. Touching on Ken Thompson’s famous talk, “Reflections on Trusting Trust”, the early goals of “Secure Computing” and UEFI firmware interfaces:

This is the core of a two-decade-old debate among security people, and it’s one that the “benevolent God” faction has consistently had the upper hand in. They’re the “curated computing” advocates who insist that preventing you from choosing an alternative app store or side-loading a program is for your own good – because if it’s possible for you to override the manufacturer’s wishes, then malicious software may impersonate you to do so, or you might be tricked into doing so. [..] This benevolent dictatorship model only works so long as the dictator is both perfectly benevolent and perfectly competent. We know the dictators aren’t always benevolent. […] But even if you trust a dictator’s benevolence, you can’t trust in their perfection. Everyone makes mistakes. Benevolent dictator computing works well, but fails badly. Designing a computer that intentionally can’t be fully controlled by its owner is a nightmare, because that is a computer that, once compromised, can attack its owner with impunity.

Lastly, Chengyu HAN updated the Reproducible Builds website to correct an incorrect Git command. […]

Debian

In Debian this month, the essential and required package sets became 100% reproducible in Debian bookworm on the amd64 and arm64 architectures. These two subsets of the full Debian archive refer to Debian package “priority” levels as described in the §2.5 Priorities section of the Debian Policy — there is no canonical “minimal installation” package set in Debian due to its diverse methods of installation.

As it happens, these package sets are not reproducible on the i386 architecture because the ncurses package on that architecture is not yet reproducible, and the sed package currently fails to build from source on armhf too. The full list of reproducible packages within these package sets can be viewed within our QA system, such as on the page of required packages in amd64 and the list of essential packages on arm64, both for Debian bullseye.

It recently has become very easy to install reproducible Debian Docker containers using podman on Debian bullseye:

$ sudo apt install podman
$ podman run --rm -it debian:bullseye bash

The (pre-built) image used is itself built using debuerrotype, as explained on docker.debian.net. This page also details how to build the image yourself and what checksums are expected if you do so.

Related to this, it has also become straightforward to reproducibly bootstrap Debian using mmdebstrap, a replacement for the usual debootstrap tool to create Debian root filesystems:

$ SOURCE_DATE_EPOCH=$(date --utc --date=2022-08-29 +%s) mmdebstrap unstable > unstable.tar

This works for (at least) Debian unstable, bullseye and bookworm, and is tested automatically by a number of QA jobs set up by Holger Levsen (unstable, bookworm and bullseye)

Work has also taken place to ensure that the canonical debootstrap and cdebootstrap tools are also capable of bootstrapping Debian reproducibly, although it currently requires a few extra steps:

  1. “Clamping” the modification time of files that are newer than $SOURCE_DATE_EPOCH to be not greater than SOURCE_DATE_EPOCH.

  2. Deleting a few files. For debootstrap, this requires the deletion of /etc/machine-id, /var/cache/ldconfig/aux-cache, /var/log/dpkg.log, /var/log/alternatives.log and /var/log/bootstrap.log, and for cdebootstrap we also need to delete the /var/log/apt/history.log and /var/log/apt/term.log files as well.

This process works at least for unstable, bullseye and bookworm and is now being tested automatically by a number of QA jobs setup by Holger Levsen […][…][…][…][…][…]. As part of this work, Holger filed two bugs to request a better initialisation of the /etc/machine-id file in both debootstrap […] and cdebootstrap […].

Elsewhere in Debian, 131 reviews of Debian packages were added, 20 were updated and 27 were removed this month, adding to our extensive knowledge about identified issues. Chris Lamb added a number of issue types, including: randomness_in_browserify_output […], haskell_abi_hash_differences […], nondeterministic_ids_in_html_output_generated_by_python_sphinx_panels […]. Lastly, Mattia Rizzolo removed the deterministic flag from the captures_kernel_variant flag […].

Other distributions

Vagrant Cascadian posted an update of the status of Reproducible Builds in GNU Guix, writing that:

Ignoring the pesky unknown packages, it is more like ~93% reproducible and ~7% unreproducible... that feels a bit better to me!

These numbers wander around over time, mostly due to packages moving back into an "unknown" state while the build farms catch up with each other... although the above numbers seem to have been pretty consistent over the last few days.

The post itself contains a lot more details, including a brief discussion of tooling.

Elsewhere in GNU Guix, however, Vagrant updated a number of packages such as itpp […], perl-class-methodmaker […], libnet […], directfb […] and mm-common […], as well as updated the version of reprotest to 0.7.21 […].

In openSUSE, Bernhard M. Wiedemann published his usual openSUSE monthly report.

diffoscope

diffoscope is our in-depth and content-aware diff utility. Not only can it locate and diagnose reproducibility issues, it can provide human-readable diffs from many kinds of binary formats. This month, Chris Lamb prepared and uploaded versions 220 and 221 to Debian, as well as made the following changes:

  • Update external_tools.py to reflect changes to xxd and the vim-common package. […]
  • Depend on the dedicated xxd package now, not the vim-common package. […]
  • Don’t crash if we can open a PDF file using the PyPDF library, but cannot subsequently parse the annotations within. […]

In addition, Vagrant Cascadian updated diffoscope in GNU Guix, first to to version 220 […] and later to 221 […].

Community news

The Reproducible Builds project aims to fix as many currently-unreproducible packages as possible as well as to send all of our patches upstream wherever appropriate. This month we created a number of patches, including:

Testing framework

The Reproducible Builds project runs a significant testing framework at tests.reproducible-builds.org, to check packages and other artifacts for reproducibility. This month, Holger Levsen made the following changes:

  • Debian-related changes:

    • Temporarily add Debian unstable deb-src lines to enable test builds a Non-maintainer Upload (NMU) campaign targeting 708 sources without .buildinfo files found in Debian unstable, including 475 in bookworm. […][…]
    • Correctly deal with the Debian Edu packages not being installable. […]
    • Finally, stop scheduling stretch. […]
    • Make sure all Ubuntu nodes have the linux-image-generic kernel package installed. […]

  • Health checks & view:

    • Detect SSH login problems. […]
    • Only report the first uninstallable package set. […]
    • Show new bootstrap jobs. […] and debian-live jobs. […] in the job health view.
    • Fix regular expression to detect various zombie jobs. […]

  • New jobs:

    • Add a new job to test reproducibility of mmdebstrap bootstrapping tool. […][…][…][…]
    • Run our new mmdebstrap job remotely […][…]
    • Improve the output of the mmdebstrap job. […][…][…]
    • Adjust the mmdebstrap script to additionally support debootstrap as well. […][…][…]
    • Work around mmdebstrap and debootstrap keeping logfiles within their artifacts. […][…][…]
    • Add support for testing cdebootstrap too and add such a job for unstable. […][…][…]
    • Use a reproducible value for SOURCE_DATE_EPOCH for all our new bootstrap jobs. […]

  • Misc changes:

    • Send the create_meta_pkg_sets notification to #debian-reproducible-changes instead of #debian-reproducible. […]

In addition, Roland Clobus re-enabled the tests for live-build images […] and added a feature where the build would retry instead of give up when the archive was synced whilst building an ISO […], and Vagrant Cascadian added logging to report the current target of the /bin/sh symlink […].

Contact

As ever, 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:

09 September, 2022 12:53PM

hackergotchi for Emmanuel Kasper

Emmanuel Kasper

“Forever loading” error with Jitsi and Google Meet

I had this issue preventing me to start a call, which happened on two different browsers. It turned out that the pulseaudio service was hung, and no audio devices were available for the browser to use.

In that case it makes sense to check:

  • if pulseaudio is running
systemctl status --user pulseaudio
  • if pulseaudio is running, that you have a list from input (sources) and output (sinks) audio devices in the Gnome Desktop Settings. You can also check from the command line with
pactl list sources
pactl list sinks

09 September, 2022 07:25AM by Manu

September 08, 2022

Antoine Beaupré

Complaint about Canada's phone cartel

I have just filed a complaint with the CRTC about my phone provider's outrageous fees. This is a copy of the complaint.

I am traveling to Europe, specifically to Ireland, for a 6 days for a work meeting.

I thought I could use my phone there. So I looked at my phone provider's services in Europe, and found the "Fido roaming" services:

https://www.fido.ca/mobility/roaming

The fees, at the time of writing, at fifteen (15!) dollars PER DAY to get access to my regular phone service (not unlimited!!).

If I do not use that "roaming" service, the fees are:

  • 2$/min
  • 0.75$/text
  • 10$/20MB

That is absolutely outrageous. Any random phone plan in Europe will be cheaper than this, by at least one order of magnitude. Just to take any example:

https://www.tescomobile.ie/sim-only-plans.aspx

Those fine folks offer a one-time, prepaid plan for €15 for 28 days which includes:

  • unlimited data
  • 1000 minutes
  • 500 text messages
  • 12GB data elsewhere in Europe

I think it's absolutely scandalous that telecommunications providers in Canada can charge so much money, especially since the most prohibitive fee (the "non-prepaid" plans) are automatically charged if I happen to forget to remove my sim card or put my phone in "airplane mode".

As advised, I have called customer service at Fido for advice on how to handle this situation. They have confirmed those are the only plans available for travelers and could not accommodate me otherwise. I have notified them I was in the process of filing this complaint.

I believe that Canada has become the technological dunce of the world, and I blame the CRTC for its lack of regulation in that matter. You should not allow those companies to grow into such a cartel that they can do such price-fixing as they wish.

I haven't investigated Fido's competitors, but I will bet at least one of my hats that they do not offer better service.

I attach a screenshot of the Fido page showing those outrageous fees.

I have no illusions about this having any effect. I thought of filing such a complain after the Rogers outage as well, but felt I had less of a standing there because I wasn't affected that much (e.g. I didn't have a life-threatening situation myself).

This, however, was ridiculous and frustrating enough to trigger this outrage. We'll see how it goes...

"We will respond to you within 10 working days."

Response from CRTC

They did respond within 10 days. Here is the full response:

Dear Antoine Beaupré:

Thank you for contacting us about your mobile telephone international roaming service plan rates concern with Fido Solutions Inc. (Fido).

In Canada, mobile telephone service is offered on a competitive basis. Therefore, the Canadian Radio-television and Telecommunications Commission (CRTC) is not involved in Fido's terms of service (including international roaming service plan rates), billing and marketing practices, quality of service issues and customer relations.

If you haven't already done so, we encourage you to escalate your concern to a manager if you believe the answer you have received from Fido's customer service is not satisfactory.

Based on the information that you have provided, this may also appear to be a Competition Bureau matter. The Competition Bureau is responsible for administering and enforcing the Competition Act, and deals with issues such as false or misleading representations, deceptive marketing practices and collusion. You can reach the Competition Bureau by calling 1-800-348-5358 (toll-free), by TTY (for deaf and hard of hearing people) by calling 1-866-694-8389 (toll-free). For more contact information, please visit http://www.competitionbureau.gc.ca/eic/site/cb-bc.nsf/eng/00157.html

When consumers are not satisfied with the service they are offered, we encourage them to compare the products and services of other providers in their area and look for a company that can better match their needs. The following tool helps to show choices of providers in your area: https://crtc.gc.ca/eng/comm/fourprov.htm

Thank you for sharing your concern with us.

In other words, complain with Fido, or change providers. Don't complain to us, we don't manage the telcos, they self-regulate.

Great job, CRTC. This is going great. This is exactly why we're one of the most expensive countries on the planet for cell phone service.

Live chat with Fido

Interestingly, the day after I received that response from the CRTC, I received this email from Fido, while traveling:

Date: Tue, 13 Sep 2022 10:10:00 -0400 From: Fido DONOTREPLY@fido.ca To: REDACTED Subject: Courriel d’avis d’itinérance | Fido

Roaming Welcome Confirmation

Fido

Date : 13 septembre 2022
Numéro de compte : [redacted]

Bonjour
Antoine Beaupré!

Nous vous écrivons pour vous indiquer qu’au moins un utilisateur inscrit à votre compte s’est récemment connecté à un réseau en itinérance.
Vous trouverez ci-dessous le message texte de bienvenue en itinérance envoyé à l’utilisateur (ou aux utilisateurs), qui contenait les tarifs d’itinérance
applicables.

Message texte de bienvenue en itinérance

Destinataire : REDACTED

Date et heure : 2022-09-13 / 10:10:00
Allo, ici Fido : Bienvenue à destination! Vous êtes inscrit à Fido Nomade alors utilisez vos données, parlez et textez comme vous le faites à la
maison. Depuis le 1 mars 2022 le tarif cette destination pour 15 $/jour (+ taxes) et valide tous les jours jusqu'à 23 h 59 HE, peu importe le fuseau
horaire dans lequel vous vous trouvez. Bon voyage! Des questions? Consultez fido.ca/m/itinerance ou composez +15149333436 (sans frais).

Besoin d’aide?

  • PLANIFIEZ UN VOYAGE AVEC Fido NomadeMC
    Découvrez nos options d’itinérance et restez en contact à l’étranger sans vous soucier de votre
    facture.

Détails

  • Gérez votre compte
    Gérez vos produits et services Fido à la maison ou sur la route grâce à Mon
    Compte.

Détails

Ce courriel est produit automatiquement; veuillez ne pas y répondre. Ce courriel (et toute pièce jointe) est confidentiel. Si vous n’êtes pas le destinataire,
veuillez supprimer le présent message et en détruire toute copie.

FIDO SOLUTIONS 800, RUE DE LA GAUCHETIÈRE OUEST
BUREAU 4000 MONTRÉAL (QUÉBEC) H5A 1K3
Fido

I found that message utterly confusing (and yes, I can read french). Basically, it says that some user (presumably me!) connected to the network with roaming. I did just disabled airplane mode on my phone to debug a Syncthing bug but had not enabled roaming.

So this message seemed to say that I would be charged 15$ (per DAY!) for roaming from now on. Confused, I tried their live chat to try to clarify things, worried I would get charged even more for calling tech support on *611. This is a transcript of the chat:

F: Hi! What are we doing today?

Type in your question or choose from the options below: * Track my Equipment Order * View Bill Online * Payment Options * iPhone 14 Pre-Order

A: i received a message about roaming while abroad but i did not enable roaming on my phone, will i be charged anyways?

F: I think I know what you’re asking for.

Select the topic that best matches your request or try rephrasing your question.

A: no

F: Thank you, this will help us to improve! Would you like to chat with a specialist?

Chat with a specialist

I'll get a specialist to help you with this.

It appears that you're not signed in. Your session may have timed out.

To save time and identify your account details, please sign in to My Account.

  • Sign in
  • I'm not able to sign in

Have any questions specific to your Fido account? To service you faster, please identify yourself by completing the form below.

A: Personal info Form submitted

F: Thank you! I'll connect you with the next available specialist.

Your chat is being transferred to a Live Chat agent. Thanks for your patience.

We are here to assist you and we kindly ask that our team members be treated with respect and dignity. Please note that abuse directed towards any Consumer Care Specialist will not be tolerated and will result in the termination of your conversation with us.

All of our agents are with other customers at the moment. Your chat is in a priority sequence and someone will be with you as soon as possible. Thanks!

Thanks for continuing to hold. An agent will be with you as soon as possible.

Thank you for your continued patience. We’re getting more Live Chat requests than usual so it’s taking longer to answer. Your chat is still in a priority sequence and will be answered as soon as an agent becomes available.

Thank you so much for your patience – we're sorry for the wait. Your chat is still in a priority sequence and will be answered as soon as possible.

Hi, I'm [REDACTED] from Fido in [REDACTED]. May I have your name please?

A: hi i am antoine, nice to meet you

sorry to use the live chat, but it's not clear to me i can safely use my phone to call support, because i am in ireland and i'm worried i'll get charged for the call

F: Thank You Antoine , I see you waited to speak with me today, thank you for your patience.Apart from having to wait, how are you today?

A: i am good thank you

[... delay ...]

A: should i restate my question?

F: Yes please what is the concern you have?

A: i have received an email from fido saying i someone used my phone for roaming

it's in french (which is fine), but that's the gist of it

i am traveling to ireland for a week

i do not want to use fido's services here... i have set the phon eto airplane mode for most of my time here

F: The SMS just says what will be the charges if you used any services.

A: but today i have mistakenly turned that off and did not turn on roaming

well it's not a SMS, it's an email

F: Yes take out the sim and keep it safe.Turun off or On for roaming you cant do it as it is part of plan.

A: wat

F: if you used any service you will be charged if you not used any service you will not be charged.

A: you are saying i need to physically take the SIM out of the phone?

i guess i will have a fun conversation with your management once i return from this trip

not that i can do that now, given that, you know, i nee dto take the sim out of this phone

fun times

F: Yes that is better as most of the customer end up using some kind of service and get charged for roaming.

A: well that is completely outrageous

roaming is off on the phone

i shouldn't get charged for roaming, since roaming is off on the phone

i also don't get why i cannot be clearly told whether i will be charged or not

the message i have received says i will be charged if i use the service

and you seem to say i could accidentally do that easily

can you tell me if i have indeed used service sthat will incur an extra charge?

are incoming text messages free?

F: I understand but it is on you if you used some data SMS or voice mail you can get charged as you used some services.And we cant check anything for now you have to wait for next bill.

and incoming SMS are free rest all service comes under roaming.

That is the reason I suggested take out the sim from phone and keep it safe or always keep the phone or airplane mode.

A: okay

can you confirm whether or not i can call fido by voice for support?

i mean for free

F: So use your Fido sim and call on +1-514-925-4590 on this number it will be free from out side Canada from Fido sim.

A: that is quite counter-intuitive, but i guess i will trust you on that

thank you, i think that will be all

F: Perfect, Again, my name is [REDACTED] and it’s been my pleasure to help you today. Thank you for being a part of the Fido family and have a great day!

A: you too

So, in other words:

  1. they can't tell me if I've actually been roaming
  2. they can't tell me how much it's going to cost me
  3. I should remove the SIM card from my phone (!?) or turn on airplane mode, but the former is safer
  4. I can call Fido support, but not on the usual *611, and instead on that long-distance-looking phone number, and yes, that means turning off airplane mode and putting the SIM card in, which contradicts step 3

Also notice how the phone number from the live chat (+1-514-925-4590) is different than the one provided in the email (15149333436). So who knows what would have happened if I would have called the latter. The former is mentioned in their contact page.

I guess the next step is to call Fido over the phone and talk to a manager, which is what the CRTC told me to do in the first place...

I ended up talking with a manager (another 1h phone call) and they confirmed there is no other package available at Fido for this. At best they can provide me with a credit if I mistakenly use the roaming by accident to refund me, but that's it. The manager also confirmed that I cannot know if I have actually used any data before reading the bill, which is issued on the 15th of every month, but only available... three days later, at which point I'll be back home anyways.

Fantastic.

08 September, 2022 02:45PM

Thorsten Alteholz

My Debian Activities in August 2022

FTP master

This month I accepted 375 and rejected 25 packages. The overall number of packages that got accepted was 386.

I also had a closer look at the RM-bugs. All in all I addressed about 90 of them and either simply removed the package or added a moreinfo tag. In total I spent 13 hours for this task.

Anyway, if you want to have your RM-bug processed in a timely manner, please have a look at the removal page and check whether the created dak command is really what you wanted. It would also help if you check the reverse dependencies and write a comment whether they are important or can be ignored or also file a new bug for them. Each removal must have one bug!

Debian LTS

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

This month my all in all workload has been 30.00h. As I started to become a Freexian collaborator in this month, I only worked 17h on the LTS project.

During that time I uploaded:

  • [#1010380] buster-pu: flac/1.3.2-3+deb10u2, upload
  • [#1009076] buster-pu: minidlna/1.2.1+dfsg-2+deb10u3, upload
  • [#1009251] buster-pu: fribidi/1.0.5-3.1+deb10u2, upload
  • [#1008578] buster-pu: golang-github-russellhaering-goxmldsig/0.0~git20170911.b7efc62-1+deb10u1, upload
  • [#1016391] bullseye-pu: libhttp-daemon-perl/6.12-1+deb11u1, upload
  • [DLA 3088-1] net-snmp security update for six CVEs
  • [unstable] mod-wsgi for one CVE

I also started to work on upx-ucl.

Debian ELTS

This month was the forty-ninth ELTS month.

During my allocated time I uploaded:

  • [ELA-655-1] libhttp-daemon-perl security update of Jessie and Stretch for one CVE
  • [ELA-659-1] mod-wsgi security update of Stretch for one CVE
  • [ELA-667-1] gst-plugins-good1.0 security update of Jessie and Stretch for seven CVEs
  • [ELA-668-1] net-snmp security update of Jessie and Stretch for six CVEs

Debian Printing

This month I uploaded new upstream versions or improved packaging of:

Debian Astro

This month I uploaded new upstream versions or improved packaging of:

08 September, 2022 10:38AM by alteholz

September 07, 2022

Antoine Beaupré

Deleted GitLab forks from my account

I have just deleted two forks I had of the GitLab project in my gitlab.com account. I did this after receiving a warning that quotas would now start to be enforced. It didn't say that I was going over quota, so I actually had to go look in the usage quotas page, which stated I was using 5.6GB of storage. So far so good, I'm not going to get billed because I'm below the 10GB threshold.

But still, I found that number puzzling. That's a lot of data! Maybe wallabako? I build images there in CI... Or the ISOs in stressant?

Nope. The biggest disk users were... my forks of gitlab-ce and gitlab-ee (now respectively called gitlab-foss and gitlab-ee, but whatever). CE was taking up roughly 1GB and EE was taking up the rest.

So I deleted both repos, which means that the next time I want to contribute a fix to their documentation — which is as far as I managed to contribute to GitLab — I will need to re-fork those humongous repositories.

Maybe I'm reading this wrong. Maybe there's a bug in the quotas system. Or, if I'm reading this right, GitLab is actually double-billing people: once for the source repository, and once for the fork. Because surely repos are not duplicating all those blobs on disk... right? RIGHT?

Either case, that's rather a bad move on their part, I feel like. With GitHub charging 4$/user/month, it feels like GitLab is going to have to trouble to compete by charging 20$/user/month as a challenger...

(Update: as noted in the comments by Jim Sorenson, this is actually an issue with older versions of GitLab. Deleting and re-forking the repos will actually fix the issue so, in a way, I did exactly what I should. Another workaround is to run the housekeeping jobs on the repo, although I cannot confirm this works myself.)

But maybe it's just me: I'm not an economist, surely there's some brilliant plan here I'm missing...

In the meantime, free-ish alternatives include Quay.io (currently free for public repos) and sr.ht (2$/mth, but at least not open-core, unfortunately no plan for a container registry). And of course, you can painfully self-host GitLab, sr.ht, gitea, pagure, or whatever it is the current fancy gitweb.

07 September, 2022 01:34AM

September 06, 2022

hackergotchi for Louis-Philippe Véronneau

Louis-Philippe Véronneau

Montreal's Debian & Stuff - August 2022

Our local Debian user group gathered on Sunday August 28th1 at the very hackish Foulab for the August 2022 edition of our "Debian & Stuff" meetings.

As always, the event was a success and we had lots of fun. Nine people showed up, including some new faces and people I hadn't seen in a while:

On my side, although I was badly sleep-deprived 2, I still managed to be somewhat productive!

One of the WiFi Access Points we use in our 4-apartment LAN had been boot-looping for a few weeks, after a failed sysupgrade to the latest version of OpenWRT. lavamind and I suspect the flash got corrupted in a way or another during the upgrade process...

Lucky for us, this model has a serial port and runs U-Boot. After a bit of tinkering, some electrical tape and two different serial adapters3, we managed to identify the pin layout and got a shell on the machine. The device has a reset button, but since the kernel panic was happening too soon in the boot process, we weren't able to get into OpenWRT's failsafe mode this way.

The WiFi AP being flashed via a serial-to-USB adapter

Once we had serial access, wiping the flash and re-installing OpenWRT fixed our problem. A quick ansible-playbook run later, the device was back to being usable and configured :)

I was too tired to keep track of what others did, but I took some nice pictures of the pizza we got, and of this nice blow-up Tux wearing a Foulab t-shirt. Enjoy!

A blow-up Tux wearing a Foulab t-shirt

One of the pizzas we ordered

As always, thanks to the Debian project for granting us a budget to rent the venue and to buy some food.

  1. Please excuse the late blog post, it's Harvest Season here and I've been quite busy. ↩

  2. A bad case of wry neck kept me from sleeping properly for a while in August. ↩

  3. As it turns out, serial connections work better when you use the right pins for TX and RX! ↩

06 September, 2022 08:15PM by Louis-Philippe Véronneau

hackergotchi for Shirish Agarwal

Shirish Agarwal

Debian on Phone

History

Before I start, the game I was talking about is called Cell To Singularity. Now I haven’t gone much in the game as I have shared but think that the Singularity it refers to is the Technological Singularity that people think will happen. Whether that will happen or not is open to debate to one and all. This is going to be a bit long one.

Confession Time :- When I was sharing in the blog post, I had no clue that we actually had sessions on it in this year’s Debconf. I just saw the schedule yesterday and then came to know. Then I saw Guido’s two talks, one at Debconf as well as one as Froscon. In fact, saw the Froscon talk first, and then the one at Debconf. Both the talks are nearly the same except for a thing here or a thing there.

Now because I was not there so my understanding and knowledge would be disadvantageously asymmetrical to Guido and others who were there and could talk and share more. Having a Debian mobile or Debian on the mobile could also make Debian more popular and connectable to the masses, one of the things that were not pointed out in the Debian India BOF sadly. At the same time, there are some facts that are not on the table and hence not thought about.

Being a B.Com person, I have been following not just the technical but also how the economics work and smartphone penetration in India is pretty low or historically been very low, say around 3-4% while the majority that people use, almost 90-95% of the market uses what are called non-smartphones or dumbphones. Especially during the pandemic and even after that the dumbphones market actually went up while smartphones stagnated and even came down. There is a lot of inventory at most of the dealers that they can’t get rid of. From a dealer perspective, it probably makes more sense to buy and sell dumbphones more in number as the turnaround of capital is much faster and easier than for smartphones. I have seen people spend a number of hours and rightly so in order to make their minds up on a smartphone while for a dumbphone, it is a 10-minute thing. Ask around, figure out who is selling at the cheapest, and just buy. Most of these low-end phones are coming from China. In fact, even in the middle and getting even into smartphones, the Chinese are the masters from whom we buy, even as they have occupied Indian territory. In the top five, Samsung comes at number three of four (sharing about Samsung as a fan and having used them.) even though battery times are atrocious, especially with Android 12L. The only hope that most of the smartphone manufacturers have is lowering the sticker prices and hoping that 5G Adoption picks up and that is what they are betting on but that comes with its own share of drawbacks as can be seen.

GNOME, MATE, memory leaks, Payments

FWIW, while I do have GNOME and do use a couple of tools from the GNOME stack, I hate GNOME with a passion. I have been a mate user for almost a decade now and really love the simplicity that mate has vis-a-vis GNOME. And with each release, MATE has only become better. So, it would be nice if we can have MATE on the mobile phone. How ‘adaptive’ the apps might be on the smaller area, I dunno. It would be interesting to find out if and how people are looking at debugging memory leaks on mobile phones. Although finding memory leaks on any platform is good, finding them and fixing them on a mobile phone is pretty much critical as most phones have fixed & relatively small amounts of memory and it is and can get quickly exhausted.

One of the things that were asked in the Q&A was about payments. The interesting thing is both UK and India are the same or markedly similar in regard as far as contactless payments being concerned. What most Indians have or use is basically UPI which is basically backed by your bank. Unlike in some other countries where you have a selection of wallets and even temporary/permanent virtual accounts whereby you can minimize your risks in case your mobile gets stolen or something, here we don’t have that. There are three digital wallets that I know – Paytm – Not used (have heard it’s creepy, but don’t really know), Google pay (Unfortunately, this is the one I use, they bought multiple features, and in the last couple of years have really taken the game away from Paytm but also creepy.). The last one is Samsung Pay (haven’t really used it as their find my phone app. always crashes, dunno how it is supposed to work.) But I do find that the apps. are vulnerable. Every day there is some or other news of fraud happening. Previously, only States like Bihar and Jharkhand used to be infamous for cybercrime as a hub, but now even States like Andhra Pradesh have joined and surpassed them :(. People have lost lakhs and crores, this is just a few days back. Some more info. on UPI can be found here and GitHub has a few implementation examples that anybody could look at and run away with it.

Balancing on three things

For any new mobile phone to crack the market, it has to balance three things. One, achieve economies of scale. Unless, that is not taken care of or done, however good or bad the product might be, it remains a niche and dies after some time. While Guido shared about Openmoko and N900, one of the more interesting bits from a user perspective at least was the OLPC project. There are many nuances that the short article didn’t go through. While I can’t say for other countries, at least in India, no education initiative happens without corruption. And perhaps Nicholas’s hands were tied while other manufacturers would and could do to achieve their sales targets. In India, it flopped because there was no way for volunteers to buy or get OLPC unless they were part of a school or college. There was some traction in FOSS communities, but that died down once OLPC did the partnership with MS-Windows, and proverbially broke the camel’s back. FWIW, I think the idea, the concept, and even the machine were far ahead of their time.

The other two legs are support and Warranty – Without going into any details, I can share and tell there were quite a few OLPC type attempts using conventional laptops or using Android and FOSS or others or even using one of the mainstream distributions but the problems have always been polishing, training and support. Guido talked about privacy as a winning feature but fails to take into account that people want to know that their privacy isn’t being violated. If a mobile phone answers to ‘Hey Google’ does it mean it was passively gathering, storing, and sending info to third parties, we just don’t know. The mobile phone could be part of ‘the right to repair’ profile while at the same time it can force us to ask many questions about the way things currently are and going to be. Six months down the line all the flagships of all companies are working on being able to take and share through satellites (Satellite Internet) and perhaps maybe a few non-flagships. Of course, if you are going to use a satellite, then you are going to drain that much more quickly. In all and every event there are always gonna be tradeoffs.

The Debian-mobile mailing list doesn’t seem to have many takers. The latest I could find there is written by Paul Wise. I am in a similar boat (Samsung; SM-M526B; Lahaina; arm64-v8a) v12. It is difficult to know which release would work on your machine, make sure that the building from the source is not tainted and pristine and needs a way to backup and restore if you need to. I even tried installing GNURoot Debian and the Xserver alternative they had shared but was unable to use the touch interface on the fakeroot instance 😦 . The system talks about a back key but what back key I have no clue.

Precursor Events Debconf 2023

As far as precursor events are concerned before Debconf 23 in India, all the festivals that we have could be used to showcase Debian. In fact, the ongoing Ganesh Chaturthi would have been the perfect way to showcase Debian and apps. according to the audience. Even the festival of Durga Puja, Diwali etc. can be used. When commercial organizations use the same festivals, why can’t we? What perhaps we would need to figure out is the funding part as well as getting permissions from Municipal authorities. One of the things for e.g. that we could do is buy either a permanent 24″ monitor or a 34″ TV and use that to display Debian and apps. The bigger, the better. Something that we could use day to day and also is used for events. This would require significant amounts of energy so we could approach companies, small businesses and individuals both for volunteering as well as helping out with funding.

Somebody asked how we could do online stuff and why it is somewhat boring. What could be done for e.g. instead of 4-5 hrs. of things, break it into manageable 45 minute pieces. 4-5 hrs. is long and is gonna fatigue the best of people. Make it into 45-minute negotiable chunks, and intersphere it with jokes, hacks, anecdotes, and war stories. People do not like or want to be talked down to but rather converse. One of the things that I saw many of the artists do is have shows and limit the audience to 20-24 people on zoom call or whatever videoconferencing system you have and play with them. The passive audience enjoys the play between the standup guy and the ‘crowd’ he works on, some of them may be known to him personally so he can push that envelope a bit more. The same thing can be applied here. Share the passion, and share why we are doing something. For e.g. you could do smem -t -k | less and give a whole talk about how memory is used and freed during a session, how are things different on desktop and ARM as far as memory architecture is concerned (if there is). What is being done on the hardware side, what is on the software side and go on and on. Then share about troubleshooting applications. Valgrind is super slow and makes life hell, is there some better app ? Doesn’t matter if you are a front-end or a back-end developer you need to know this and figure out the best way to deal with in your app/program. That would have lot of value. And this is just an e.g. to help trigger more ideas from the community. I am sure others probably have more fun ideas as to what can be done. I am stopping here now otherwise would just go on, till later. Feel free to comment, feedback. Hope it generates some more thinking and excitement on the grey cells.

06 September, 2022 04:41PM by shirishag75

September 04, 2022

hackergotchi for Junichi Uekawa

Junichi Uekawa

September.

September. Digging into why my apt-get doesn't complete.

04 September, 2022 02:28AM by Junichi Uekawa

September 03, 2022

James Valleroy

File sharing with bepasty

One of the apps running on my FreedomBox that I use frequently is bepasty. bepasty is essentially a self-hosted, free software pastebin. It allows you to paste text, or upload any type of file. You can also set an expiration date for when the file or text will automatically be deleted. If you are uploading multiple related files, you can organize them into a list.

bepasty does not have user accounts. Instead, it has shared passwords, where each password is linked to a set of permissions. There are five permissions: Read, List, Create, Delete, and Admin. (The meanings are mostly straightforward, except for Admin, which means the ability to lock and unlock files.) This allows very fine-grained control. For example, if you want someone to be able to upload files to your bepasty, but not view or download anything, than you can generate a password with only the “Create” permission, and give this password to the person who will be uploading files.

To simplify the initial setup in FreedomBox, we generate three passwords by default: one for viewers (List and Read), one for editors (List, Read, Create, and Delete), and one for admins (all permissions). In addition, when no password has been provided, the Read (but not List) permission is provided by default. This allows files to be easily shared by sending just their URLs (and no password required). The URLs contain some random characters, so it is not easy to guess.

I mostly use bepasty for moving files between systems, whether its a physical machine or VPS, or a VM or container that I will use only briefly. Especially in the latter case, it’s nice that I don’t need to do any extra setup (such as copying SSH keys) before I copy my files over.

The bepasty package is available in Debian stable (with a newer version in stable-backports and testing). The many use-cases that it provides, and the well-maintained Debian packaging, made it a compelling choice for integration into FreedomBox, which has included bepasty for one-click installation since version 20.14.

03 September, 2022 02:22PM by James Valleroy

hackergotchi for Joachim Breitner

Joachim Breitner

More recursive definitions

Haskell is a pure and lazy programming language, and the laziness allows us to write some algorithms very elegantly, by recursively referring to already calculated values. A typical example is the following definition of the Fibonacci numbers, as an infinite stream:

Elegant graph traversals

A maybe more practical example is the following calculation of the transitive closure of a graph:

We represent graphs as maps from vertex to their successors vertex, and define the resulting map sets recursively: The set of reachable vertices from a vertex v is v itself, plus those reachable by its successors vs, for which we query sets.

And, despite this apparent self-referential recursion, it works!

Cyclic graphs ruin it all

These tricks can be very impressive … until someone tries to use it on a cyclic graph and the program just hangs until we abort it:

At this point we are thrown back to implement a more pedestrian graph traversal, typically keeping explicit track of vertices that we have seen already:

I have written that seen/todo recursion idiom so often in the past, I can almost write it blindly And indeed, this code handles cyclic graphs just fine:

ghci> transitive2 $ M.fromList [(1,[2,3]),(2,[1,3]),(3,[])]
fromList [(1,[1,2,3]),(2,[1,2,3]),(3,[3])]

But this is a bit anticlimactic – Haskell is supposed to be a declarative language, and transitive1 declares my intent just fine!

We can have it all

It seems there actually is a way to write essentially the code in transitive1, and still get the right result in all cases, and I have just published a possible implementation as rec-def. In the module Data.Recursive.Set we find an API that resembles that of Set, with a type RSet a, and in addition to conversion functions from and to sets, we find the two operations that we needed in transitive1:

Let’s try that:

And indeed it works! Magic!

ghci> transitive2 $ M.fromList [(1,[3]),(2,[1,3]),(3,[])]
fromList [(1,[1,3]),(2,[1,2,3]),(3,[3])]
ghci> transitive2 $ M.fromList [(1,[2,3]),(2,[1,3]),(3,[])]
fromList [(1,[1,2,3]),(2,[1,2,3]),(3,[3])]

To show off some more, here are small examples:

ghci> let s = RS.insert 42 s in RS.get s
fromList [42]
ghci> :{
  let s1 = RS.insert 23 s2
      s2 = RS.insert 42 s1
  in RS.get s1
 :}
fromList [23,42]

How is that possible? Is it still Haskell?

The internal workings of the RSet a type will be the topic of a future blog post; let me just briefly mention that it uses unsafe features under the hood, and just keeps applying the equations you gave until a fixed-point is reached. Because it starts with the empty set and all operations provided by Data.Recursive.Set are monotonous (e.g. no difference) it will eventually find the least fixed point.

Despite the unsafe machinery under the hood, I claim that Data.Recursive.Set is itself nicely safe, and does not destroy Haskell’s nice properties like purity, referential transparency and equational reasoning. If you disagree, I’d like to hear about it (here, on Twitter, Reddit or Discourse)! There is a brief discussion at the end of the tutorial in Data.Recursive.Example.

More than sets

The library also provides Data.Recursive.Bool for recursive equations with booleans (preferring False) and Data.Recursive.DualBool (preferring True), and some operations like member :: Ord a => a -> RSet a -> RBool can actually connect different types. I plan to add other data types (natural numbers, maps, Maybe, with suitable orders) as demand arises and as I come across nice small example use-cases for the documentation (e.g. finding shortest paths in a graph).

I believe this idiom is practically useful in a wide range of applications (which of course all have some underlying graph structure – but then almost everything in Computer Science is a graph). My original motivation was a program analysis. Imagine you want to find out from where in your program you can run into a division by zero. As long as your program does not have recursion, you can simply keep track of a boolean flag while you traverse the program, keeping track a mapping from function names to whether they can divide by zero – all nice and elegant. But once you allow mutually recursive functions, things become tricky. Unless you use RBool! Simply use laziness, pass the analysis result down when analyzing the function’s right-hand sides, and it just works!

03 September, 2022 12:31PM by Joachim Breitner (mail@joachim-breitner.de)

hackergotchi for Shirish Agarwal

Shirish Agarwal

Fantasy, J.R.R. Tolkein

J.R.R. Tolkein

Now unless you have been living under a rock cave, I am sure you know who Mr. Tolkein is. Apparently, the gentleman passed away on 2nd September 1973 at the sprightly age of 80. And this gives fans like me to talk about fantasy, fantasy authors, and the love-hate relationship we have with them. For a matter of record, I am currently reading Babylon Steel by Gaie Sebold. Now while I won’t go into many details (I never like to, if I enjoy a book, I would want the book to be mysterious rather than give praise, simply so that the next person enjoys it as much as I did without having any expectations.) Now this book has plenty of sex so wouldn’t recommend it for teenagers but more perhaps to mature audiences, although for the life of me couldn’t find any rating on the book. I did come across common sense media but unfortunately, it isn’t well known beyond perhaps some people who use it. They sadly don’t have a google/Android app 😦 And before anybody comments, I know that Android is no longer interested in supporting FOSS, their loss, not ours but that is entirely a blog post/article in itself. so let’s leave that aside for now.

Fantasy

So before talking about Mr. Tolkien and his creations let’s talk and share a bit about fantasy. We know for a fact that the conscious mind functions at less than 5%, while the other bits are made by the subconscious and the unconscious mind (the three mind model.) So any thought or idea first germinates n either the unconscious or the subconscious part of the mind and then comes into the conscious mind. It is the reason we also dream. That’s the subconscious and unconscious mind at work. While we say fantasy mostly to books, it is all around us and not just in prose but in song, dance, and all sorts of creativity are fantasy. Even Sci-fi actually comes from fantasy. Unfortunately, for reasons best known to people, they took out sci-fi and even divided fantasy into high fantasy and low fantasy. I am not going to go much into that but here’s a helpful link for those who might want to look more into it. Now the question arises, why do people write? I have asked this question many a time to the authors I have met and the answers are as varied as they come. Two of the most common answers are the need to write (an itch they can’t control or won’t control) and the other is it’s extremely healing. In my own case, even writing mere blog posts I found it unburdening & cathartetic. I believe this last part is what drove Mr. Tolkein and the story and arc that LOTR became.

Tolkien, LOTR, World War I

The casual reader might not know but if you followed or were curious about Mr. Tolkien, you would have found out that Mr. Tolkien served in World War 1 or what is known as the Great War. It was supposed to be the war that ended all wars but sadly didn’t. One of the things that set apart Mr. Tolkein from many of his peers was that Mr. Tolkien was very straight about himself and corresponded with people far and wide. There is actually a book called ‘The Letters of J.R.R. Tolkien’ that I hope to get at one of the used book depots. That book spans about 480 pages and gives all the answers as to why Mr. Tolkien made Middle-earth as it was made. I sadly haven’t had the opportunity to get it and it is somewhat expensive. But I’m sure that if World War 1 wouldn’t have happened and Mr. Tolkein hadn’t taken part and experienced what he experienced, we wouldn’t have LOTR. I can bet losing his friends and comrades, and the pain he felt for those around him propelled him to write about land and a race called Hobbits. I haven’t done enough fantasy reading but I do feel that his description of hobbits and the way they were and are is unique. The names and surnames he used were for humor as well as to make a statement about them. Having names such as Harfoots, Padfoot, Took and others just wouldn’t be for fun, would it? Also, the responses and the behavior in the four books by Hobbits are almost human-like. It is almost like they are or were our cousins at one point in time but we allowed ourselves to forget. Even the corruption of humans has been shown as well as self-doubt.

There is another part that I found and find fascinating, unlike most books where there is a single hero, in LOTR we have many heroes and heroines. This again, I would attribute to Mr. Tolkien and the heroism he saw on the battlefield and beyond it. All the tender emotions he shares with readers like us are because either he himself or others around him were subjected to grace and wonderment. This is all I derive from the books, those who have ‘The letters of J.R.R. Tolkein’, feel free to correct me. I was supposed to write this yesterday but real life has its own way.

I could go on and on, perhaps at a later date or time I may expand on it, but it isn’t a coincidence that ‘Lord of the Rings: Rings of Power’ is starting broadcast on the same day when Mr. Tolkein died. In the very end, fantasy is something humans got and does not matter how rich or poor you are. If one were to look, both artists like Michaelangelo and many other artists, who often didn’t have enough to have two square meals in the day, but still somehow were inspired to sketch models of airplanes, flying machines which are shockingly similar to the real thing. Many may not know that almost all primates, including apes, monkeys, squirrels, and even dolphins dream. And all of them have elaborate, complex dreams just as we do. Sadly, this info. is not known by most people otherwise, we would be so much empathetic towards our cousins in the animal kingdom.

03 September, 2022 05:02AM by shirishag75

September 02, 2022

Kunal Mehta

Kiwix in Debian, 2022 update

Previous updates: 2018, 2021

Kiwix is an offline content reader, best known for distributing copies of Wikipedia. I have been maintaining it in Debian since 2017.

This year most of the work has been keeping all the packages up to date in anticipation of next year's Debian 12 Bookworm release, including several transitions for new libzim and libkiwix versions.

  • libzim: 6.3.0 → 8.0.0
  • zim-tools: 2.1.0 → 3.1.1
  • python-libzim: 0.0.3 → 1.1.1 (with a cherry-picked patch)
  • libkiwix: 9.4.1 → 11.0.0 (with DFSG issues fixed!)
  • kiwix-tools: 3.1.2 → 3.3.0
  • kiwix (desktop): 2.0.5 → 2.2.2

The Debian Package Tracker makes it really easy to keep an eye on all Kiwix-related packages.

All of the "user-facing" packages (zim-tools, kiwix-tools, kiwix) now have very basic autopkgtests that can provide a bit of confidence that the package isn't totally broken. I recommend reading the "FAQ for package maintainers" to learn about all the benefits you get from having autopkgtests.

Finally, back in March I wrote a blog post, How to mirror the Russian Wikipedia with Debian and Kiwix, which got significant readership (compared to most posts on this blog), including being quoted by LWN!

We are always looking for more contributors, please reach out if you're interested. The Kiwix team is one of my favorite groups of people to work with and they love Debian too.

02 September, 2022 03:06AM by legoktm

John Goerzen

Dead USB Drives Are Fine: Building a Reliable Sneakernet

“OK,” you’re probably thinking. “John, you talk a lot about things like Gopher and personal radios, and now you want to talk about building a reliable network out of… USB drives?”

Well, yes. In fact, I’ve already done it.

What is sneakernet?

Normally, “sneakernet” is a sort of tongue-in-cheek reference to using disconnected storage to transport data or messages. By “disconnect storage” I mean anything like CD-ROMs, hard drives, SD cards, USB drives, and so forth. There are times when loading up 12TB on a device and driving it across town is just faster and easier than using the Internet for the same. And, sometimes you need to get data to places that have no Internet at all.

Another reason for sneakernet is security. For instance, if your backup system is online, and your systems being backed up are online, then it could become possible for an attacker to destroy both your primary copy of data and your backups. Or, you might use a dedicated computer with no network connection to do GnuPG (GPG) signing.

What about “reliable” sneakernet, then?

TCP is often considered a “reliable” protocol. That means that the sending side is generally able to tell if its message was properly received. As with most reliable protocols, we have these components:

  1. After transmitting a piece of data, the sender retains it.
  2. After receiving a piece of data, the receiver sends an acknowledgment (ACK) back to the sender.
  3. Upon receiving the acknowledgment, the sender removes its buffered copy of the data.
  4. If no acknowledgment is received at the sender, it retransmits the data, in case it gets lost in transit.
  5. It reorders any packets that arrive out of order, so that the recipient’s data stream is ordered correctly.

Now, a lot of the things I just mentioned for sneakernet are legendarily unreliable. USB drives fail, CD-ROMs get scratched, hard drives get banged up. Think about putting these things in a bicycle bag or airline luggage. Some of them are going to fail.

You might think, “well, I’ll just copy files to a USB drive instead of move them, and once I get them onto the destination machine, I’ll delete them from the source.” Congratulations! You are a human retransmit algorithm! We should be able to automate this!

And we can.

Enter NNCP

NNCP is one of those things that almost defies explanation. It is a toolkit for building asynchronous networks. It can use as a carrier: a pipe, TCP network connection, a mounted filesystem (specifically intended for cases like this), and much more. It also supports multi-hop asynchronous routing and asynchronous meshing, but these are beyond the scope of this particular article.

NNCP’s transports that involve live communication between two hops already had all the hallmarks of being reliable; there was a positive ACK and retransmit. As of version 8.7.0, NNCP’s ACKs themselves can also be asynchronous – meaning that every NNCP transport can now be reliable.

Yes, that’s right. Your ACKs can flow over tapes and USB drives if you want them to.

I use this for archiving and backups.

If you aren’t already familiar with NNCP, you might take a look at my NNCP page. I also have a lot of blog posts about NNCP.

Those pages describe the basics of NNCP: the “packet” (the unit of transmission in NNCP, which can be tiny or many TB), the end-to-end encryption, and so forth. The new command we will now be interested in is nncp-ack.

The Basic Idea

Here are the basic steps to processing this stuff with NNCP:

  1. First, we use nncp-xfer -rx to process incoming packets from the USB (or other media) device. This moves them into the NNCP inbound queue, deleting them from the media device, and verifies the packet integrity.
  2. We use nncp-ack -node $NODE to create ACK packets responding to the packets we just loaded into the rx queue. It writes a list of generated ACKs onto fd 4, which we save off for later use.
  3. We run nncp-toss -seen to process the incoming queue. The use of -seen causes NNCP to remember the hashes of packets seen before, so a duplicate of an already-seen packet will not be processed twice. This command also processes incoming ACKs for packets we’ve sent out previously; if they pass verification, the relevant packets are removed from the local machine’s tx queue.
  4. Now, we use nncp-xfer -keep -tx -mkdir -node $NODE to send outgoing packets to a given node by writing them to a given directory on the media device. -keep causes them to remain in the outgoing queue.
  5. Finally, we use the list of generated ACK packets saved off in step 2 above. That list is passed to nncp-rm -node $NODE -pkt < $FILE to remove those specific packets from the outbound queue. The reason is that there will never be an ACK of ACK packet (that would create an infinite loop), so if we don’t delete them in this manner, they would hang around forever.

You can see these steps follow the same basic outline on upstream’s nncp-ack page.

One thing to keep in mind: if anything else is running nncp-toss, there is a chance of a race condition between steps 1 and 2 (if nncp-toss gets to it first, it might not get an ack generated). This would sort itself out eventually, presumably, as the sender would retransmit and it would be ACKed later.

Further ideas

NNCP guarantees the integrity of packets, but not ordering between packets; if you need that, you might look into my Filespooler program. It is designed to work with NNCP and can provide ordered processing.

An example script

Here is a script you might try for this sort of thing. It may have more logic than you need – really, you just need the steps above – but hopefully it is clear.

#!/bin/bash

set -eo pipefail

MEDIABASE="/media/$USER"

# The local node name
NODENAME="`hostname`"

# All nodes.  NODENAME should be in this list.
ALLNODES="node1 node2 node3"

RUNNNCP=""
# If you need to sudo, use something like RUNNNCP="sudo -Hu nncp"
NNCPPATH="/usr/local/nncp/bin"

ACKPATH="`mktemp -d`"

# Process incoming packets.
#
# Parameters: $1 - the path to scan.  Must contain a directory
# named "nncp".
procrxpath () {
    while [ -n "$1" ]; do
        BASEPATH="$1/nncp"
        shift
        if ! [ -d "$BASEPATH" ]; then
            echo "$BASEPATH doesn't exist; skipping"
            continue
        fi

        echo " *** Incoming: processing $BASEPATH"
        TMPDIR="`mktemp -d`"

        # This rsync and the one below can help with
        # certain permission issues from weird foreign
        # media.  You could just eliminate it and
        # always use $BASEPATH instead of $TMPDIR below.
        rsync -rt "$BASEPATH/" "$TMPDIR/"

        # You may need these next two lines if using sudo as above.
        # chgrp -R nncp "$TMPDIR"
        # chmod -R g+rwX "$TMPDIR"
        echo "     Running nncp-xfer -rx"
        $RUNNNCP $NNCPPATH/nncp-xfer -progress -rx "$TMPDIR"

        for NODE in $ALLNODES; do
                if [ "$NODE" != "$NODENAME" ]; then
                        echo "     Running nncp-ack for $NODE"

                        # Now, we generate ACK packets for each node we will
                        # process.  nncp-ack writes a list of the created
                        # ACK packets to fd 4.  We'll use them later.
                        # If using sudo, add -C 5 after $RUNNNCP.
                        $RUNNNCP $NNCPPATH/nncp-ack -progress -node "$NODE" \
                           4>> "$ACKPATH/$NODE"
                fi
        done

        rsync --delete -rt "$TMPDIR/" "$BASEPATH/"
        rm -fr "$TMPDIR"
    done
}


proctxpath () {
    while [ -n "$1" ]; do
        BASEPATH="$1/nncp"
        shift
        if ! [ -d "$BASEPATH" ]; then
            echo "$BASEPATH doesn't exist; skipping"
            continue
        fi

        echo " *** Outgoing: processing $BASEPATH"
        TMPDIR="`mktemp -d`"
        rsync -rt "$BASEPATH/" "$TMPDIR/"
        # You may need these two lines if using sudo:
        # chgrp -R nncp "$TMPDIR"
        # chmod -R g+rwX "$TMPDIR"

        for DESTHOST in $ALLNODES; do
            if [ "$DESTHOST" = "$NODENAME" ]; then
                continue
            fi

            # Copy outgoing packets to this node, but keep them in the outgoing
            # queue with -keep.
            $RUNNNCP $NNCPPATH/nncp-xfer -keep -tx -mkdir -node "$DESTHOST" -progress "$TMPDIR"

            # Here is the key: that list of ACK packets we made above - now we delete them.
            # There will never be an ACK for an ACK, so they'd keep sending forever
            # if we didn't do this.
            if [ -f "$ACKPATH/$DESTHOST" ]; then
                echo "nncp-rm for node $DESTHOST"
                $RUNNNCP $NNCPPATH/nncp-rm -debug -node "$DESTHOST" -pkt < "$ACKPATH/$DESTHOST"
            fi

        done

        rsync --delete -rt "$TMPDIR/" "$BASEPATH/"
        rm -rf "$TMPDIR"

        # We only want to write stuff once.
        return 0
    done
}

procrxpath "$MEDIABASE"/*

echo " *** Initial tossing..."

# We make sure to use -seen to rule out duplicates.
$RUNNNCP $NNCPPATH/nncp-toss -progress -seen

proctxpath "$MEDIABASE"/*

echo "You can unmount devices now."

echo "Done."

This post is also available on my webiste, where it may be periodically updated.

02 September, 2022 01:43AM by John Goerzen

September 01, 2022

hackergotchi for Emmanuel Kasper

Emmanuel Kasper

OpenShift vs. AWS product mapping

If you know the Amazon Web Services portfolio, and you are interested in OpenShift or the OKD OpenShift community distribution, this is a table of corresponding technologies.

OpenShift is Red Hat’s Kubernetes distribution: it is basically the upstream Kubernetes delivered with monitoring, logging, CI/CD, underlying OS, tested upgrade paths not found with a manual kubernetes.io kubeadm install.

AWS OpenShift OpenShift upstream project
Cloud Trail Kubernetes API Server audit log Kubernetes
Cloud Watch OpenShift Monitoring Prometheus
AWS Artifact Compliance Operator OpenSCAP
AWS Trusted Advisor Insights
AWS Marketplace OpenShift Operator Hub
AWS Identity and Access Management (IAM) Red Hat SSO Keycloack
AWS Elastisc Beanstalk OpenShift Source2Image (S2I) Source2Image (S2I)
AWS S3 ODF Rados Gateway Rook RGW
AWS Elastic Bloc Storage ODF Rados Block Device Rook RBD
AWS Elastic File System ODF Ceph FS Rook CephFS
Amazon Simple Notification Service OpenShift Streams for Apache Kafka Apache Kafka
Amazon Guard Duty API Server audit log review, ACS Runtime detection Stackrox
Amazon Inspector Quay.io container scanner, ACS Vulnerability Assessment Clair, Stackrox
AWS Lambda Openshift Serverless* Knative
AWS Key Management System could be done with Hashicorp Vault Vault
AWS WAF NGINX Ingress Controller Operator with ModSecurity NGINX ModSecurity
Amazon Elasticache Redis Enterprise Operator Redis, memcached as alternative
AWS Relational Database Service Crunchy Data Operator PostgreSQL

* OpenShift Serverless requires the application to be packaged as a container, something AWS Lamda does not require.

01 September, 2022 07:45AM by Manu

Russ Allbery

Summer haul

It's been a while since I posted one of these! Or, really, much of anything else. Busy and distracted this summer and a bit behind on a wide variety of things at the moment, although thankfully not in a bad way.

Sara Alfageeh & Nadia Shammas — Squire (graphic novel)
Travis Baldree — Legends & Lattes (sff)
Leigh Bardugo — Six of Crows (sff)
Miles Cameron — Artifact Space (sff)
Robert Caro — The Power Broker (nonfiction)
Kate Elliott — Servant Mage (sff)
Nicola Griffith — Spear (sff)
Alix E. Harrow — A Mirror Mended (sff)
Tony Judt — Postwar (nonfiction)
T. Kingfisher — Nettle & Bone (sff)
Matthys Levy & Mario Salvadori — Why Buildings Fall Down (nonfiction)
Lev Menand — The Fed Unbound (nonfiction)
Courtney Milan — Trade Me (romance)
Elie Mystal — Allow Me to Retort (nonfiction)
Quenby Olson — Miss Percy's Pocket Guide (sff)
Anu Partanen — The Nordic Theory of Everything (nonfiction)
Terry Pratchett — Hogfather (sff)
Terry Pratchett — Jingo (sff)
Terry Pratchett — The Last Continent (sff)
Terry Pratchett — Carpe Jugulum (sff)
Terry Pratchett — The Fifth Elephant (sff)
Terry Pratchett — The Truth (sff)
Victor Ray — On Critical Race Theory (nonfiction)
Richard Roberts — A Spaceship Repair Girl Supposedly Named Rachel (sff)
Nisi Shawl & Latoya Peterson (ed.) — Black Stars (sff anthology)
John Scalzi — The Kaiju Preservation Society (sff)
James C. Scott — Seeing Like a State (nonfiction)
Mary Sisson — Trang (sff)
Mary Sisson — Trust (sff)
Benjanun Sriduangkaew — And Shall Machines Surrender (sff)
Lea Ypi — Free (nonfiction)

It's been long enough that I've already read and reviewed some of these. Already read and pending review are the next two Pratchett novels in my slow progress working through them. Had to catch up with the Tor.com re-read series.

So many books and quite definitely not enough time at the moment, although I've been doing better at reading this summer than last summer!

01 September, 2022 05:26AM

Paul Wise

FLOSS Activities August 2022

Focus

This month I didn't have any particular focus. I just worked on issues in my info bubble.

Changes

Issues

Debugging

  • Did extensive debugging on a libpst issue but failed to figure out the cause of the issue. Seems to be related to a change to freopen in glibc that fixed compatibility with POSIX.

Review

  • FOSSjobs: approved postings
  • Spam: reported 5 Debian bug reports and 23 Debian mailing list posts
  • Debian packages: sponsored psi-notify (twice)
  • Debian wiki: RecentChanges for the month
  • Debian BTS usertags: changes for the month
  • Debian screenshots:
    • approved bible-kjv edb-debugger lifeograph links mu-editor unattended-upgrades
    • rejected apt-listchanges/apt-listdifferences (semi-related log file), steam-devices (package description), myspell-es/lighttpd (selfie), fraqtive (Windows), wireguard (logo), kde-telepathy-contact-list (mobile hacking app)

Administration

  • Debian BTS: unarchive/reopen/triage bugs for reintroduced packages orage, scap-security-guide, libdatetime-format-datemanip-perl
  • Debian IRC: disable anti-spam channel modes for some channels
  • Debian servers: investigate full filesystems
  • Debian wiki: unblock IP addresses, approve accounts, ping accounts with bouncing email

Communication

  • Respond to queries from Debian users and contributors on the mailing lists and IRC.

Sponsors

The sptag, libpst, purple-discord, circuitbreaker work was sponsored. All other work was done on a volunteer basis.

01 September, 2022 04:32AM