Recently I have been looking at how to control and collect data from a handful IP cameras using Linux. I both wanted to change their settings and to make their imagery available via a free software service under my control. Here is a summary of the tools I found. First I had to identify the cameras and their protocols. As far as I could tell, they were using some SOAP looking protocol and their internal web server seem to only work with Microsoft Internet Explorer with some proprietary binary plugin, which in these days of course is a security disaster and also made it impossible for me to use the camera web interface. Luckily I discovered that the SOAP looking protocol is actually following the ONVIF specification, which seem to be supported by a lot of IP cameras these days. Once the protocol was identified, I was able to find what appear to be the most popular way to configure ONVIF cameras, the free software Windows tool named ONVIF Device Manager. Lacking any other options at the time, I tried unsuccessfully to get it running using Wine, but was missing a dotnet 40 library and I found no way around it to run it on Linux. The next tool I found to configure the cameras were a non-free Linux Qt client ONVIF Device Tool. I did not like its terms of use, so did not spend much time on it. To collect the video and make it available in a web interface, I found the Zoneminder tool in Debian. A recent version was able to automatically detect and configure ONVIF devices, so I could use it to set up motion detection in and collection of the camera output. I had initial problems getting the ONVIF autodetection to work, as both Firefox and Chromium refused the inter-tab communication being used by the Zoneminder web pages, but managed to get konqueror to work. Apparently the "Enhanced Tracking Protection" in Firefox cause the problem. I ended up upgrading to the Bookworm edition of Zoneminder in the process to try to fix the issue, and believe the problem might be solved now. In the process I came across the nice Linux GUI tool ONVIF Viewer allowing me to preview the camera output and validate the login passwords required. Sadly its author has grown tired of maintaining the software, so it might not see any future updates. Which is sad, as the viewer is sightly unstable and the picture tend to lock up. Note, this lockup might be due to limitations in the cameras and not the viewer implementation. I suspect the camera is only able to provide pictures to one client at the time, and the Zoneminder feed might interfere with the GUI viewer. I have asked for the tool to be included in Debian. Finally, I found what appear to be very nice Linux free software replacement for the Windows tool, named libonvif. It provide a C library to talk to ONVIF devices as well as a command line and GUI tool using the library. Using the GUI tool I was able to change the admin passwords and update other settings of the cameras. I have asked for the package to be included in Debian. As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b. Update 2022-10-20: Since my initial publication of this text, I got several suggestions for more free software Linux tools. There is a ONVIF python library (already requested into Debian) and a python 3 fork using a different SOAP dependency. There is also support for ONVIF in Home Assistant, and there is an alternative to Zoneminder called Shinobi. The latter two are not included in Debian either. I have not tested any of these so far.

I first installed Ubuntu when Ubuntu 6.06 LTS Dapper Drake was released. I was brand new to Linux. This was Ubuntu s first LTS release; the very first release of Ubuntu was only a year and a half before. I was impressed by how usable and useful the system was. It soon became my primary home operating system and I wanted to help make it better. On October 15, 2009, I was helping test the release candidates ISOs for the Ubuntu 9.10 release. Specifically, I tested Edubuntu. Edubuntu has since been discontinued but at the time it was an official Ubuntu flavor preloaded with lots of education apps. One of those education apps was Moodle, an e-learning platform. When testing Moodle, I found that a default installation would make Moodle impossible to use locally. I figured out how to fix this issue. This was really exciting: I finally found an Ubuntu bug I knew how to fix. I filed the bug report. This was very late in the Ubuntu 9.10 release process and Ubuntu was in the Final Freeze state. In Final Freeze, every upload to packages included in the default install need to be individually approved by a member of the Ubuntu Release Team. Also, I didn t have upload rights to Ubuntu. Jordan Mantha (LaserJock), an Edubuntu maintainer, sponsored my bug fix upload. I also forwarded my patch to Debian. While trying to figure out what wasn t working with Moodle, I stumbled across a packaging bug. Edubuntu provided a choice of MySQL or PostgreSQL for the system default database. MySQL was the default, but if PostgreSQL were chosen instead, Moodle wouldn t work. I figured out how to fix this bug too a week later. Jordan sponsored this upload and Steve Langasek from the Release Team approved it so it also was able to be fixed before 9.10 was released. Although the first bug was new to 9.10 because of a behavior change in a low-level dependency, this PostgreSQL bug existed in stable Ubuntu releases. Therefore, I prepared Stable Release Updates for Ubuntu 9.04 and Ubuntu 8.04 LTS. Afterwards Six months later, I was able to attend my first Ubuntu Developer Summit. I was living in Bahrain (in the Middle East) at the time and a trip to Belgium seemed easier to me than if I were living in the United States where I usually live. This was the Ubuntu Developer Summit where planning for Ubuntu 10.10 took place. I like to believe that I helped with the naming since I added Maverick to the wiki page where people contribute suggestions. I did not apply for financial sponsorship to attend and I stayed in a budget hotel on the other side of Brussels. The event venue was on the outskirts of Brussels so there wasn t a direct bus or metro line to get there. I rented a car. I didn t yet have a smartphone and I had a LOT of trouble navigating to and from the site every day. I learned then that it s best to stay close to the conference site since a lot of the event is actually in the unstructured time in the evenings. Fortunately, I managed to arrive in time for Mark Shuttleworth s keynote where the Unity desktop was first announced. This was released in Ubuntu 10.10 in the Ubuntu Netbook Remix and became the default for Ubuntu Desktop in Ubuntu 11.04. Ubuntu s switch to Unity provided me with a huge opportunity. In April 2011, GNOME 3.0 was released. I wanted to try it but it wasn t yet packaged in Ubuntu or Debian. It was suggested that I could help work on packaging the major new version in a PPA. The PPA was convenient because I was able to get permission to upload there easier than being able to upload directly to Ubuntu. My contributions there then enabled me to get upload rights to the Ubuntu Desktop packages later that year. At a later Ubuntu Developer Summit, it was suggested that I start an official Ubuntu flavor for GNOME. So along with Tim Lunn (darkxst), I co-founded Ubuntu GNOME. Years later, Canonical stopped actively developing Unity; instead, Ubuntu GNOME was merged into Ubuntu Desktop. Along the way, I became an Ubuntu Core Developer and a Debian Developer. And in January 2022, I joined Canonical on the Desktop Team. This all still feels amazing to me. It took me a long time to be comfortable calling myself a developer! Conclusion My first Ubuntu bugfix was 13 years ago this week. Because Ubuntu historically uses alphabetical adjective animal release names, 13 years means that we have rolled around to the letter K again! Later today, we begin release candidate ISO testing for Ubuntu 22.10 Kinetic Kudu . I encourage you to help us test the release candidates and report bugs that you find. If you figure out how to fix a bug, we still sponsor bug fixes. If you are an Ubuntu contributor, I highly encourage you to attend an Ubuntu Summit if you can. The first Ubuntu Summit in years will be in 3 weeks in Prague, but the intent is for the Ubuntu Summits to be recurring events again.

The purpose of this post is to demonstrate a first approach to the analysis of multiwavelength kinetic data, like those obtained using stopped-flow data. To practice, we will use data that were acquired during the stopped flow practicals of the MetBio summer school from the FrenchBIC. During the practicals, the student monitored the reaction of myoglobin (in its Fe(III) state) with azide, which yields a fast and strong change in the absorbance spectrum of the protein, which was monitored using a diode array. The data is publicly available on zenodo. Aims of this tutorial The purpose of this tutorial is to teach you to use the free softwareQSoas to run a simple, multiwavelength exponential fit on the data, and to look at the results. This is not a kinetics lecture, so that it will not go in depth about the use of the exponential fit and its meaning. Getting started: loading the file First, make sure you have a working version of QSoas, you can download them (for free) there. Then download the data files from zenodo. We will work only on the data file Azide-1.25mm_001.dat, but of course, the purpose of this tutorial is to enable you to work on all of them. The data files contain the time evolution of the absorbance for all wavelengths, in a matrix format, in which each row correpond to a time point and each column to a wavelength. Start QSoas, and launch the command:

QSoas> load /comments='"'

Then, choose the Azide-1.25mm_001.dat data file. This should bring up a horizontal red line at the bottom of the data display, with X values between about 0 and 2.5. If you zoom on the red line with the mouse wheel, you'll realize it is data. The /comments='"' part is very important since it allows the extraction of the wavelength from the data. We will look at what it means another day. At this stage, you can look at the loaded data using the command:

QSoas> edit

You should have a window looking like this:

The rows each correspond to a data point displayed on the window below. The first column correspond to the X values, the second the Y values, and all the other ones to extra Y columns (they are not displayed by default). What is especially interesting is the first row, which contains a nan as the X value and what is obviously the wavelength for all the Y values. To tell that QSoas should take this line as the wavelength (which will be the perpendicular coordinate, the coordinate of the other direction of the matrix), first close the edit window and run:

QSoas> set-perp /from-row=0

Splitting and fitting Now, we have a single dataset containing a lot of Y columns. We want to fit all of them simultaneously with a (mono) exponential fit. For that, we first need to split the big matrix into a series of X,Y datasets (because fitting only works on the first Y). This is possible by running:

QSoas> expand /style=red-to-blue /flags=kinetics

Your screen should now look like this:

You're looking at the kinetics at all wavelengths at the same time (this may take some time to display on your computer, it is after all a rather large number of data points). The /style=red-to-blue is not strictly necessary, but it gives the red to blue color gradient which makes things easier to look at (and cooler !). The /flags=kinetics is there to attach a label (a flag) to the newly created datasets so we can easily manipulate all of them at the same time. Then it's time to fit, with the following command:

QSoas> mfit-exponential-decay flagged:kinetics

This should bring up a new window. After resizing it, you should have something that looks like this:

The bottom of the fit window is taken by the parameters, each with two checkboxes on the right to set them fixed (i.e. not determined by the fitting mechanism) and/or global (i.e. with a single value for all the datasets, here all the wavelengths). The top shows the current dataset along with the corresponding fit (in green), and, below, the residuals. You can change the dataset by clicking on the horizontal arrows or using Ctrl+PgUp or Ctrl+PgDown (keep holding it to scan fast). See the Z = 728.15 showing that QSoas has recognized that the currently displayed dataset corresponds to the wavelength 728.15. The equation fitted to the data is: $$y(x) = A_\infty + A_1 \times \exp -(x - x_0)/\tau_1$$ In this case, while the $A_1$ and $A_\infty$ parameters clearly depend on the wavelength, the time constant of evolution should be independent of wavelength (the process happens at a certain rate regardless of the wavelength we're analyzing), so that the $\tau_1$ parameter should be common for all the datasets/wavelengths. Just click on the global checkbox at the right of the tau_1 parameter, make sure it is checked, and hit the Fit button... The fit should not take long (less than a minute), and then you end up with the results of the fits: all the parameters. The best way to look at the non global parameters like $A_1$ and $A_\infty$ is to use the Show Parameters item from the Parameters menu. Using it and clicking on A_inf too should give you a display like this one:

The A_inf parameter corresponds to the spectum at infinite time (of azide-bound heme), while the A_1 parameter corresponds to the difference spectrum between the initial (azide-free) and final (azide-bound) states. Now, the fit is finished, you can save the parameters if you want to reload them in a later fit by using the Parameters/Save menu item or export them in a form more suitable for plotting using Parameters/Export (although QSoas can also display and the parameters saved using Save). This concludes this first approach to fitting the data. What you can do is

look at the depence of the tau_1 parameter as a function of the azide concentration;

try fitting more than one exponential, using for instance:

QSoas> mfit-exponential-decay /exponentials=2 flagged:kinetics

How to read the code above All the lines starting by QSoas> in the code areas above are meant to be typed into the QSoas command line (at the bottom of the window), and started by pressing enter at the end. You must remove the QSoas> bit. The other lines (when applicable) show you the response of QSoas, in the terminal just above the command-line. You may want to play with the QSoas tutorial to learn more about how to interact with QSoas. 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 freely (and at no cost) download its source code or precompiled versions for MacOS and Windows there. Alternatively, you can clone from the GitHub repository.
Contact: find my email address there, or contact me on LinkedIn.

I ve released a new tool to manage lockfiles for Arch Linux packages that can t use a lockfile from the official upstream release. It integrates closely with other Arch Linux tooling like updpkgsums that s already used to pin the content of build inputs in PKGBUILD. To use this, the downstream lockfile becomes an additional source input in the source= array of our PKGBUILD (this is already the case for some packages).

source=("git+https://github.com/vimeo/psalm.git#commit=$ _commit "
        "composer.lock")

You would then add a new function named updlockfiles that can generate new lockfiles and copies them into $outdir, and a prepare function to copy the lockfile in the right place:

 prepare()  
   cd $ pkgname 
   cp ../composer.lock .
 
updlockfiles()  
  cd $ pkgname 
  rm -f composer.lock
  composer update
  cp composer.lock "$ outdir /"
 

To update the package to the latest (compatible) patch level simply run:

updlockfiles

This can also be used in case upstreams lockfile has vulnerable dependencies that you want to patch downstream. For more detailed instructions see the readme.

Thanks This work is currently crowd-funded on github sponsors. I d like to thank @SantiagoTorres, @repi and @rgacogne for their support in particular.

Debian does not officially support upgrading from earlier than the previous stable release: you re not supposed to skip releases. Instead, you re supposed to upgrade to each intervening major release in turn. However, skipping intervening releases does, in fact, often work quite well. Apparently, this is surprising to many people, even Debian insiders. I was encouraged to write about it some more. My personal experience I have three conventionally-managed personal server systems (by which I mean systems which aren t reprovisioned by some kind of automation). Of these at least two have been skip upgraded at least once: The one I don t think I ve skip-upgraded (at least, not recently) is my house network manager (and now VM host) which I try to keep to a minimum in terms of functionality and which I keep quite up to date. It was crossgraded from i386 (32-bit) to amd64 (64-bit) fairly recently, which is a thing that Debian isn t sure it supports. The crossgrade was done a hurry and without any planning, prompted by Spectre et al suddenly requiring big changes to Xen. But it went well enough. My home does random stuff server (media server, web cache, printing, DNS, backups etc.), has etckeeper records starting in 2015. I upgraded directly from jessie (Debian 8) to buster (Debian 10). I think it has probably had earlier skip upgrade(s): the oldest file in /etc is from December 1996 and I have been doing occasional skip upgrades as long as I can remember. And of course there s chiark, which is one of the oldest Debian installs in existence. I wrote about the most recent upgrade, where I went directly from jessie i386 ELTS (32-bit Debian 8) to bulleye amd64 (64-bit Debian 11). That was a very extreme case which required significant planning and pre-testing, since the package dependencies were in no way sufficient for the proper ordering. But, I don t normally go to such lengths. Normally, even on chiark, I just edit the sources.list and see what apt proposes to do. I often skip upgrade chiark because I tend to defer risky-looking upgrades partly in the hope of others fixing the bugs while I wait :-), and partly just because change is disruptive and amortising it is very helpful both to me and my users. I have some records of chiark s upgrades from my announcements to users. As well as the recent skip skip up cross grade, direct , I definitely did a skip upgrade of chiark from squeeze (Debian 6) to jessie (Debian 8). It appears that the previous skip upgrade on chiark was rex (Debian 1.2) to hamm (Debian 2.0). I don t think it s usual for me to choose to do a multi-release upgrade the officially supported way, in two (or more) stages, on a server. I have done that on systems with a GUI desktop setup, but even then I usually skip the intermediate reboot(s). When to skip upgrade (and what precautions to take) I m certainly not saying that everyone ought to be doing this routinely. Most users with a Debian install that is older than oldstable probably ought to reinstall it, or do the two-stage upgrade. Skip upgrading almost always runs into some kind of trouble (albeit, usually trouble that isn t particularly hard to fix if you know what you re doing). However, officially supported non-skip upgrades go wrong too. Doing a two-or-more-releases upgrade via the intermediate releases can expose you to significant bugs in the intermediate releases, which were later fixed. Because Debian s users and downstreams are cautious, and Debian itself can be slow, it is common for bugs to appear for one release and then be fixed only in the next. Paradoxically, this seems to be especially true with the kind of big and scary changes where you d naively think the upgrade mechanisms would break if you skipped the release where the change first came in. I would not recommend a skip upgrade to someone who is not a competent Debian administrator, with good familiarity with Debian package management, including use of dpkg directly to fix things up. You should have a mental toolkit of manual bug workaround techniques. I always should make sure that I have rescue media (and in the case of a remote system, full remote access including ability to boot a different image), although I don t often need it. And, when considering a skip upgrade, you should be aware of the major changes that have occurred in Debian. Skip upgrading is more likely to be a good idea with a complex and highly customised system: a fairly vanilla install is not likely to encounter problems during a two-stage update. (And, a vanilla system can be upgraded by reinstalling.) I haven t recently skip upgraded a laptop or workstation. I doubt I would attempt it; modern desktop software seems to take a much harder line about breaking things that are officially unsupported, and generally trying to force everyone into the preferred mold. A request to Debian maintainers I would like to encourage Debian maintainers to defer removing upgrade compatibility machinery until it is actually getting in the way, or has become hazardous, or many years obsolete. Examples of the kinds of things which it would be nice to keep, and which do not usually cause much inconvenience to retain, are dependency declarations (particularly, alternatives), and (many) transitional fragments in maintainer scripts. If you find yourself needing to either delete some compatibility feature, or refactor/reorganise it, I think it is probably best to delete it. If you modify it significantly, the resulting thing (which won t be tested until someone uses it in anger) is quite likely to have bugs which make it go wrong more badly (or, more confusingly) than the breakage that would happen without it. Obviously this is all a judgement call. I m not saying Debian should formally support skip upgrades, to the extent of (further) slowing down important improvements. Nor am I asking for any change to the routine approach to (for example) transitional packages (i.e. the technique for ensuring continuity of installation when a package name changes). We try to make release upgrades work perfectly; but skip upgrades don t have to work perfectly to be valuable. Retaining compatibility code can also make it easier to provide official backports, and it probably helps downstreams with different release schedules. The fact that maintainers do in practice often defer removing compatibility code provides useful flexibility and options to at least some people. So it would be nice if you d at least not go out of your way to break it. Building on older releases I would also like to encourage maintainers to provide source packages in Debian unstable that will still build on older releases, where this isn t too hard and the resulting binaries might be basically functional. Speaking personally, it s not uncommon for me to rebuild packages from unstable and install them on much older releases. This is another thing that is not officially supported, but which often works well. I m not saying to contort your build system, or delay progress. You ll definitely want to depend on a recentish debhelper. But, for example, retaining old build-dependency alternatives is nice. Retaining them doesn t constitute a promise that it works - it just makes life slightly easier for someone who is going off piste. If you know you have users on multiple distros or multiple releases, and wish to fully support them, you can go further, of course. Many of my own packages are directly buildable, or even directly installable, on older releases.

comments

This entry explains how I have configured a linux bridge, dnsmasq and iptables to be able to run and communicate different virtualization systems and containers on laptops running Debian GNU/Linux. I ve used different variations of this setup for a long time with VirtualBox and KVM for the Virtual Machines and Linux-VServer, OpenVZ, LXC and lately Docker or Podman for the Containers.

Required packagesI m running Debian Sid with systemd and network-manager to configure the WiFi and Ethernet interfaces, but for the bridge I use bridge-utils with ifupdown (as I said this setup is old, I guess ifupdow2 and ifupdown-ng will work too). To start and stop the DNS and DHCP services and add NAT rules when the bridge is brought up or down I execute a script that uses:

ip from iproute2 to get the network information,
dnsmasq to provide the DNS and DHCP services (currently only the dnsmasq-base package is needed and it is recommended by network-manager, so it is probably installed),
iptables to configure NAT (for now docker kind of forces me to keep using iptables, but at some point I d like to move to nftables).

To make sure you have everything installed you can run the following command:

sudo apt install bridge-utils dnsmasq-base ifupdown iproute2 iptables

Bridge configurationThe bridge configuration for ifupdow is available on the file /etc/network/interfaces.d/vmbr0:

# Virtual servers NAT Bridge
auto vmbr0
iface vmbr0 inet static
    address         10.0.4.1
    network         10.0.4.0
    netmask         255.255.255.0
    broadcast       10.0.4.255
    bridge_ports    none
    bridge_maxwait  0
    up              /usr/local/sbin/vmbridge $ IFACE  start nat
    pre-down        /usr/local/sbin/vmbridge $ IFACE  stop nat

Warning: To use a separate file with ifupdown make sure that /etc/network/interfaces contains the line:

source /etc/network/interfaces.d/*

or add its contents to /etc/network/interfaces directly, if you prefer.

This configuration creates a bridge with the address 10.0.4.1 and assumes that the machines connected to it will use the 10.0.4.0/24 network; you can change the network address if you want, as long as you use a private range and it does not collide with networks used in your Virtual Machines all should be OK. The vmbridge script is used to start the dnsmasq server and setup the NAT rules when the interface is brought up and remove the firewall rules and stop the dnsmasq server when it is brought down.

The vmbridge scriptThe vmbridge script launches an instance of dnsmasq that binds to the bridge interface (vmbr0 in our case) that is used as DNS and DHCP server. The DNS server reads the /etc/hosts file to publish local DNS names and forwards all the other requests to the the dnsmasq server launched by NetworkManager that is listening on the loopback interface. As this server already does catching we disable it for our server, with the added advantage that, if we change networks, new requests go to the new resolvers because the DNS server handled by NetworkManager gets restarted and flushes its cache (this is useful if we connect to a new network that has internal DNS servers that are configured to do split DNS for internal services; if we use this model all requests get the internal address as soon as the DNS server is queried again). The DHCP server is configured to provide IPs to unknown hosts for a sub range of the addresses on the bridge network and use fixed IPs if the /etc/ethers file has a MAC with a matching hostname on the /etc/hosts file. To make things work with old DHCP clients the script also adds checksums to the DHCP packets using iptables (when the interface is not linked to a physical device the kernel does not add checksums, but we can fix it adding a rule on the mangle table). If we want external connectivity we can pass the nat argument and then the script creates a MASQUERADE rule for the bridge network and enables IP forwarding. The script source code is the following:

/usr/local/sbin/vmbridge

#!/bin/sh
set -e
# ---------
# VARIABLES
# ---------
LOCAL_DOMAIN="vmnet"
MIN_IP_LEASE="192"
MAX_IP_LEASE="223"
# ---------
# FUNCTIONS
# ---------
get_net()  
  NET="$(
    ip a ls "$ BRIDGE " 2>/dev/null   sed -ne 's/^.*inet \(.*\) brd.*$/\1/p'
  )"
  [ "$NET" ]   return 1
 
checksum_fix_start()  
  iptables -t mangle -A POSTROUTING -o "$ BRIDGE " -p udp --dport 68 \
    -j CHECKSUM --checksum-fill 2>/dev/null   true
 
checksum_fix_stop()  
  iptables -t mangle -D POSTROUTING -o "$ BRIDGE " -p udp --dport 68 \
    -j CHECKSUM --checksum-fill 2>/dev/null   true
 
nat_start()  
  [ "$NAT" = "yes" ]   return 0
  # Configure NAT
  iptables -t nat -A POSTROUTING -s "$ NET " ! -d "$ NET " -j MASQUERADE
  # Enable forwarding (just in case)
  echo 1 >/proc/sys/net/ipv4/ip_forward
 
nat_stop()  
  [ "$NAT" = "yes" ]   return 0
  iptables -t nat -D POSTROUTING -s "$ NET " ! -d "$ NET " \
    -j MASQUERADE 2>/dev/null   true
 
do_start()  
  # Bridge address
  _addr="$ NET%%/* "
  # DNS leases (between .MIN_IP_LEASE and .MAX_IP_LEASE)
  _dhcp_range="$ _addr%.* .$ MIN_IP_LEASE ,$ _addr%.* .$ MAX_IP_LEASE "
  # Bridge mtu
  _mtu="$(
    ip link show dev "$ BRIDGE "  
      sed -n -e '/mtu/   s/^.*mtu \([0-9]\+\).*$/\1/p  '
  )"
  # Compute extra dnsmasq options
  dnsmasq_extra_opts=""
  # Disable gateway when not using NAT
  if [ "$NAT" != "yes" ]; then
    dnsmasq_extra_opts="$dnsmasq_extra_opts --dhcp-option=3"
  fi
  # Adjust MTU size if needed
  if [ -n "$_mtu" ] && [ "$_mtu" -ne "1500" ]; then
    dnsmasq_extra_opts="$dnsmasq_extra_opts --dhcp-option=26,$_mtu"
  fi
  # shellcheck disable=SC2086
  dnsmasq --bind-interfaces \
    --cache-size="0" \
    --conf-file="/dev/null" \
    --dhcp-authoritative \
    --dhcp-leasefile="/var/lib/misc/dnsmasq.$ BRIDGE .leases" \
    --dhcp-no-override \
    --dhcp-range "$ _dhcp_range " \
    --domain="$ LOCAL_DOMAIN " \
    --except-interface="lo" \
    --expand-hosts \
    --interface="$ BRIDGE " \
    --listen-address "$ _addr " \
    --no-resolv \
    --pid-file="$ PIDF " \
    --read-ethers \
    --server="127.0.0.1" \
    $dnsmasq_extra_opts
  checksum_fix_start
  nat_start
 
do_stop()  
  nat_stop
  checksum_fix_stop
  if [ -f "$ PIDF " ]; then
    kill "$(cat "$ PIDF ")"   true
    rm -f "$ PIDF "
  fi
 
do_status()  
  if [ -f "$ PIDF " ] && kill -HUP "$(cat "$ PIDF ")"; then
    echo "dnsmasq RUNNING"
  else
    echo "dnsmasq NOT running"
  fi
 
do_reload()  
  [ -f "$ PIDF " ] && kill -HUP "$(cat "$ PIDF ")"
 
usage()  
  echo "Uso: $0 BRIDGE (start stop [nat]) status reload"
  exit 1
 
# ----
# MAIN
# ----
[ "$#" -ge "2" ]   usage
BRIDGE="$1"
OPTION="$2"
shift 2
NAT="no"
for arg in "$@"; do
  case "$arg" in
  nat) NAT="yes" ;;
  *) echo "Unknown arg '$arg'" && exit 1 ;;
  esac
done
PIDF="/var/run/vmbridge-$ BRIDGE -dnsmasq.pid"
case "$OPTION" in
start) get_net && do_start ;;
stop) get_net && do_stop ;;
status) do_status ;;
reload) get_net && do_reload ;;
*) echo "Unknown command '$OPTION'" && exit 1 ;;
esac
# vim: ts=2:sw=2:et:ai:sts=2

NetworkManager ConfigurationThe default /etc/NetworkManager/NetworkManager.conf file has the following contents:

[main]
plugins=ifupdown,keyfile
[ifupdown]
managed=false

Which means that it will leave interfaces managed by ifupdown alone and, by default, will send the connection DNS configuration to systemd-resolved if it is installed. As we want to use dnsmasq for DNS resolution, but we don t want NetworkManager to modify our /etc/resolv.conf we are going to add the following file (/etc/NetworkManager/conf.d/dnsmasq.conf) to our system:

/etc/NetworkManager/conf.d/dnsmasq.conf

[main]
dns=dnsmasq
rc-manager=unmanaged

and restart the NetworkManager service:

$ sudo systemctl restart NetworkManager.service

From now on the NetworkManager will start a dnsmasq service that queries the servers provided by the DHCP servers we connect to on 127.0.0.1:53 but will not touch our /etc/resolv.conf file.

Configuring systemd-resolvedIf we start using our own name server but our system has systemd-resolved installed we will no longer need or use the DNS stub; programs using it will use our dnsmasq server directly now, but we keep running systemd-resolved for the host programs that use its native api or access it through /etc/nsswitch.conf (when libnss-resolve is installed). To disable the stub we add a /etc/systemd/resolved.conf.d/disable-stub.conf file to our machine with the following content:

# Disable the DNS Stub Listener, we use our own dnsmasq
[Resolve]
DNSStubListener=no

and restart the systemd-resolved to make sure that the stub is stopped:

$ sudo systemctl restart systemd-resolved.service

Adjusting /etc/resolv.confFirst we remove the existing /etc/resolv.conf file (it does not matter if it is a link or a regular file) and then create a new one that contains at least the following line (we can add a search line if is useful for us):

nameserver 10.0.4.1

From now on we will be using the dnsmasq server launched when we bring up the vmbr0 for multiple systems:

as our main DNS server from the host (if we use the standard /etc/nsswitch.conf and libnss-resolve is installed it is queried first, but the systemd-resolved uses it as forwarder by default if needed),
as the DNS server of the Virtual Machines or containers that use DHCP for network configuration and attach their virtual interfaces to our bridge,
as the DNS server of docker containers that get the DNS information from /etc/resolv.conf (if we have entries that use loopback addresses the containers that don t use the host network tend to fail, as those addresses inside the running containers are not linked to the loopback device of the host).

TestingAfter all the configuration files and scripts are in place we just need to bring up the bridge interface and check that everything works:

$ # Bring interface up
$ sudo ifup vmbr0
$ # Check that it is available
$ ip a ls dev vmbr0
4: vmbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN
          group default qlen 1000
    link/ether 0a:b8:ef:b8:07:6c brd ff:ff:ff:ff:ff:ff
    inet 10.0.4.1/24 brd 10.0.4.255 scope global vmbr0
       valid_lft forever preferred_lft forever
$ # View the listening ports used by our dnsmasq servers
$ sudo ss -tulpan   grep dnsmasq
udp UNCONN 0 0  127.0.0.1:53     0.0.0.0:* users:(("dnsmasq",pid=1733930,fd=4))
udp UNCONN 0 0  10.0.4.1:53      0.0.0.0:* users:(("dnsmasq",pid=1705267,fd=6))
udp UNCONN 0 0  0.0.0.0%vmbr0:67 0.0.0.0:* users:(("dnsmasq",pid=1705267,fd=4))
tcp LISTEN 0 32 10.0.4.1:53      0.0.0.0:* users:(("dnsmasq",pid=1705267,fd=7))
tcp LISTEN 0 32 127.0.0.1:53     0.0.0.0:* users:(("dnsmasq",pid=1733930,fd=5))
$ # Verify that the DNS server works on the vmbr0 address
$ host www.debian.org 10.0.4.1
Name: 10.0.4.1
Address: 10.0.4.1#53
Aliases:
www.debian.org has address 130.89.148.77
www.debian.org has IPv6 address 2001:67c:2564:a119::77

Managing running systemsIf we want to update DNS entries and/or MAC addresses we can edit the /etc/hosts and /etc/ethers files and reload the dnsmasq configuration using the vmbridge script:

$ sudo /usr/local/sbin/vmbridge vmbr0 reload

That call sends a signal to the running dnsmasq server and it reloads the files; after that we can refresh the DHCP addresses from the client machines or start using the new DNS names immediately.

Welcome to the September 2022 report from the Reproducible Builds project! In our reports we try to 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. If you are interested in contributing to the project, please visit our Contribute page on our website.

David A. Wheeler reported to us that 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 David remarked in his post to our mailing list, it expressly recommends having reproducible builds as part of advanced recommended mitigations . The publication of this document has been accompanied by a press release.

Holger Levsen was made aware of a small Microsoft project called oss-reproducible. Part of, OSSGadget, a larger collection of tools for analyzing open source packages , the purpose of oss-reproducible is to:

analyze open source packages for reproducibility. We start with an existing package (for example, the NPM left-pad package, version 1.3.0), and we try to answer the question, Do the package contents authentically reflect the purported source code?

More details can be found in the README.md file within the code repository.

David A. Wheeler also pointed out that there are some potential upcoming changes to the OpenSSF Best Practices badge for open source software in relation to reproducibility. Whilst the badge programme has three certification levels ( passing , silver and gold ), the gold level includes the criterion that The project MUST have a reproducible build . David reported that some projects have argued that this reproducibility criterion should be slightly relaxed as outlined in an issue on the best-practices-badge GitHub project. Essentially, though, the claim is that the reproducibility requirement doesn t make sense for projects that do not release built software, and that timestamp differences by themselves don t necessarily indicate malicious changes. Numerous pragmatic problems around excluding timestamps were raised in the discussion of the issue.

Sonatype, a pioneer of software supply chain management , issued a press release month to report that they had found:

[ ] a massive year-over-year increase in cyberattacks aimed at open source project ecosystems. According to early data from Sonatype s 8th annual State of the Software Supply Chain Report, which will be released in full this October, Sonatype has recorded an average 700% jump in repository attacks over the last three years.

More information is available in the press release.

A number of changes were made to the Reproducible Builds website and documentation this month, including Chris Lamb adding a redirect from /projects/ to /who/ in order to keep old or archived links working [ ], Jelle van der Waa added a Rust programming language example for SOURCE_DATE_EPOCH [ ][ ] and Mattia Rizzolo included Protocol Labs amongst our project-level sponsors [ ].

Debian There was a large amount of reproducibility work taking place within Debian this month:

The `nfft` source package was removed from the archive, and now all packages in Debian bookworm now have a corresponding `.buildinfo` file. This can be confirmed and tracked on the associated page on the tests.reproducible-builds.org site.

Vagrant Cascadian announced on our mailing list an informal online sprint to help clear the huge backlog of reproducible builds patches submitted by performing NMU (Non-Maintainer Uploads). The first such sprint took place on September 22nd with the following results:

Holger Levsen:

Mailed #1010957 in `man-db` asking for an update and whether to remove the patch tag for now. This was subsequently removed and the maintainer started to address the issue.

Uploaded `gmp` to `DELAYED/15`, fixing #1009931.

Emailed #1017372 in `plymouth` and asked for the maintainer s opinion on the patch. This resulted in the maintainer improving Vagrant s original patch (and uploading it) as well as filing an issue upstream.

Uploaded `time` to `DELAYED/15`, fixing #983202.

Vagrant Cascadian:

Verify and updated patch for `mylvmbackup` (#782318)

Verified/updated patches for `libranlip`. (#788000, #846975 & #1007137)

Uploaded `libranlip` to `DELAYED/10`.

Verified patch for `cclive`. (#824501)

Uploaded `cclive` to `DELAYED/10`.

Vagrant was unable to reproduce the underlying issue within #791423 (`linuxtv-dvb-apps`) and so the bug was marked as done .

Researched #794398 (in `clhep`).

The plan is to repeat these sprints every two weeks, with the next taking place on Thursday October 6th at 16:00 UTC on the `#debian-reproducible` IRC channel.

Roland Clobus posted his 13th update of the status of reproducible Debian ISO images on our mailing list. During the last month, Roland ensured that the live images are now automatically fed to openQA for automated testing after they have been shown to be reproducible. Additionally Roland asked on the debian-devel mailing list about a way to determine the canonical timestamp of the Debian archive. [ ]

Following up on last month s work on reproducible bootstrapping, Holger Levsen filed two bugs against the debootstrap and cdebootstrap utilities. (#1019697 & #1019698)

Lastly, 44 reviews of Debian packages were added, 91 were updated and 17 were removed this month adding to our knowledge about identified issues. A number of issue types have been updated too, including the descriptions of `cmake_rpath_contains_build_path` [ ], `nondeterministic_version_generated_by_python_param` [ ] and `timestamps_in_documentation_generated_by_org_mode` [ ]. Furthermore, two new issue types were created: `build_path_used_to_determine_version_or_package_name` [ ] and `captures_build_path_via_cmake_variables` [ ].

Other distributions 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 `222` and `223` to Debian, as well as made the following changes:

The `cbfstools` utility is now provided in Debian via the `coreboot-utils` package so we can enable that functionality within Debian. [ ]

Looked into Mach-O support.

Fixed the try.diffoscope.org service by addressing a compatibility issue between `glibc`/`seccomp` that was preventing the Docker-contained diffoscope instance from spawning any external processes whatsoever [ ]. I also updated the `requirements.txt` file, as some of the specified packages were no longer available [ ][ ].

In addition Jelle van der Waa added support for `file` version 5.43 [ ] and Mattia Rizzolo updated the packaging:

Also include `coreboot-utils` in the `Build-Depends` and `Test-Depends` fields so that it is available for tests. [ ]

Use pep517 and pip to load the requirements. [ ]

Remove packages in `Breaks`/`Replaces` that have been obsoleted since the release of Debian bullseye. [ ]

Reprotest reprotest is our end-user tool to build the same source code twice in widely and deliberate different environments, and checking whether the binaries produced by the builds have any differences. This month, reprotest version `0.7.22` was uploaded to Debian unstable by Holger Levsen, which included the following changes by Philip Hands:

Actually ensure that the `setarch(8)` utility can actually execute before including an architecture to test. [ ]

Include all files matching `.deb` in the default `artifact_pattern` in order to archive all results of the build. [ ]

Emit an error when building the Debian package if the Debian packaging version does not patch the Python version of reprotest. [ ]

Remove an unneeded invocation of the `head(1)` utility. [ ]

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

Bernhard M. Wiedemann (18 bugs):

`DateTime` (fails to build in 2038)

`FreeRCT` (date-related issue)

`clanlib1` (filesystem ordering)

`cli` (fails to build in 2038)

`deepin-gettext-tools` (patch+version update toolchain sort python glob)

`mariadb` (fails to build in 2038)

`mercurial` (fails to build in 2038)

`mirrormagic` (parallelism-related issue)

`ocaml-extlib` (parallelism-related issue)

`python-xmlrpc/python-softlayer` (fails to build in 2038)

`python` (fails to build in 2038)

`q3rally` (zip-related issue)

`rnd_jue` (parallelism-related issue)

`rsync` (workaround an issue in GCC 7.x)

`scons` (`SOURCE_DATE_EPOCH`-related issue)

`stratagus` (date-related issue)

`triplane` (nondeterminism caused by uninitialised memory)

`tyrquake` (date-related issue)

Chris Lamb:

#1019382 filed against `gnome-online-accounts`.

There was renewed activity on a reproducibility-related bug in the Sphinx documentation tool this month. Originally filed in October 2021 by Chris Lamb, the bug in question relates to contents of the `LANGUAGE` environment variable inconsistently affecting the output of `objects.inv` files.

Jelle van der Waa:

`mp4v2` (date-related issue)

`mm-common` (uid/gid issue)

`aardvark-dns` (date-related issue)

Vagrant Cascadian (70 bugs!):

#1020648 filed against `extrepo-data`.

#1020650 filed against `tmpreaper`.

#1020651 filed against `xmlrpc-epi`.

#1020653 filed against `pal`.

#1020656 filed against `nvram-wakeup`.

#1020657 filed against `netris`.

#1020658 filed against `netpbm-free`.

#1020659 filed against `lookup`.

#1020660 filed against `logtools`.

#1020661 filed against `libid3tag`.

#1020662 filed against `log4cpp`.

#1020665 filed against `libimage-imlib2-perl`.

#1020668 filed against `jnettop`.

#1020670 filed against `gwaei`.

#1020671 filed against `ipfm`.

#1020672 filed against `tarlz`.

#1020673 filed against `w3cam`.

#1020674 filed against `ifstat`.

#1020715 filed against `xserver-xorg-input-joystick`.

#1020719 filed against `chibicc`.

#1020723 filed against `python-omegaconf`.

#1020724 and #1020725 filed against `snapper`.

#1020736 filed against `libreswan`.

#1020743 filed against `pure-ftpd`.

#1020748 filed against `xcolmix`.

#1020749 filed against `gigalomania`.

#1020750 filed against `xjump`.

#1020751 filed against `waili`.

#1020752 filed against `sjeng`.

#1020753 filed against `seqtk`.

#1020754 filed against `shapetools`.

#1020755 filed against `rotter`.

#1020756 filed against `rakarrack`.

#1020757 filed against `rig`.

#1020759 filed against `postal`.

#1020798 filed against `netkit-rsh`.

#1020800 filed against `libapache-mod-evasive`.

#1020804 filed against `paxctl`.

#1020805 filed against `png23d`.

#1020806 filed against `perl-byacc`.

#1020807 filed against `poster`.

#1020808 filed against `powerdebug`.

#1020809 filed against `aespipe`.

#1020810 filed against `aewm++-goodies`.

#1020811 filed against `apache-upload-progress-module`.

#1020812 filed against `ascii2binary`.

#1020813 filed against `bible-kjv`.

#1020814 filed against `dradio`.

#1020815 filed against `libapache2-mod-python`.

#1020816 filed against `tempest-for-eliza`.

#1020817 filed against `aplus-fsf`.

#1020866 filed against `wrapsrv`.

#1020867 filed against `uclibc`.

#1020870 filed against `xppaut`.

#1020872 filed against `xvier`.

#1020873 filed against `xserver-xorg-video-glide`.

#1020875 filed against `z80asm`.

#1020876 filed against `yaskkserv`.

#1020877 filed against `edid-decode`.

#1020878 filed against `dustmite`.

#1020879 filed against `dustmite`.

#1020880 filed against `libapache2-mod-authnz-pam`.

#1020881 filed against `kafs-client`.

#1020882 filed against `yaku-ns`.

#1020884 filed against `bplay`.

#1020886 filed against `chise-base`.

#1020887 filed against `checkpw`.

#1020888 filed against `clamz`.

#1020889 filed against `libapache2-mod-auth-pgsql`.

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

Holger Levsen:

Add a job to build reprotest from Git [ ] and use the correct Git branch when building it [ ].

Mattia Rizzolo:

Enable syncing of results from building live Debian ISO images. [ ]

Use `scp -p` in order to preserve modification times when syncing live ISO images. [ ]

Apply the shellcheck shell script analysis tool. [ ]

In a build node wrapper script, remove some debugging code which was messing up calling `scp(1)` correctly [ ] and consquently add support to use both `scp -p` and regular `scp` [ ].

Roland Clobus:

Track and handle the case where the Debian archive gets updated between two live image builds. [ ]

Remove a call to `sudo(1)` as it is not (or no longer) required to delete old live-build results. [ ]

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:

IRC: `#reproducible-builds` on `irc.oftc.net`.

Twitter: @ReproBuilds

Mailing list: `rb-general@lists.reproducible-builds.org`

Fast laptops are expensive, cheap laptops are slow. But even a fast laptop is slower than a decent workstation, and if your developers want a local build environment they're probably going to want a decent workstation. They'll want a fast (and expensive) laptop as well, though, because they're not going to carry their workstation home with them and obviously you expect them to be able to work from home. And in two or three years they'll probably want a new laptop and a new workstation, and that's even more money. Not to mention the risks associated with them doing development work on their laptop and then drunkenly leaving it in a bar or having it stolen or the contents being copied off it while they're passing through immigration at an airport. Surely there's a better way?

This is the thinking that leads to "Let's give developers a Chromebook and a VM running in the cloud". And it's an appealing option! You spend far less on the laptop, and the VM is probably cheaper than the workstation - you can shut it down when it's idle, you can upgrade it to have more CPUs and RAM as necessary, and you get to impose all sorts of additional neat security policies because you have full control over the network. You can run a full desktop environment on the VM, stream it to a cheap laptop, and get the fast workstation experience on something that weighs about a kilogram. Your developers get the benefit of a fast machine wherever they are, and everyone's happy.

But having worked at more than one company that's tried this approach, my experience is that very few people end up happy. I'm going to give a few reasons here, but I can't guarantee that they cover everything - and, to be clear, many (possibly most) of the reasons I'm going to describe aren't impossible to fix, they're simply not priorities. I'm also going to restrict this discussion to the case of "We run a full graphical environment on the VM, and stream that to the laptop" - an approach that only offers SSH access is much more manageable, but also significantly more restricted in certain ways. With those details mentioned, let's begin.

The first thing to note is that the overall experience is heavily tied to the protocol you use for the remote display. Chrome Remote Desktop is extremely appealing from a simplicity perspective, but is also lacking some extremely key features (eg, letting you use multiple displays on the local system), so from a developer perspective it's suboptimal. If you read the rest of this post and want to try this anyway, spend some time working with your users to find out what their requirements are and figure out which technology best suits them.

Second, let's talk about GPUs. Trying to run a modern desktop environment without any GPU acceleration is going to be a miserable experience. Sure, throwing enough CPU at the problem will get you past the worst of this, but you're still going to end up with users who need to do 3D visualisation, or who are doing VR development, or who expect WebGL to work without burning up every single one of the CPU cores you so graciously allocated to their VM. Cloud providers will happily give you GPU instances, but that's going to cost more and you're going to need to re-run your numbers to verify that this is still a financial win. "But most of my users don't need that!" you might say, and we'll get to that later on.

Next! Video quality! This seems like a trivial point, but if you're giving your users a VM as their primary interface, then they're going to do things like try to use Youtube inside it because there's a conference presentation that's relevant to their interests. The obvious solution here is "Do your video streaming in a browser on the local system, not on the VM" but from personal experience that's a super awkward pain point! If I click on a link inside the VM it's going to open a browser there, and now I have a browser in the VM and a local browser and which of them contains the tab I'm looking for WHO CAN SAY. So your users are going to watch stuff inside their VM, and re-compressing decompressed video is going to look like shit unless you're throwing a huge amount of bandwidth at the problem. And this is ignoring the additional irritation of your browser being unreadable while you're rapidly scrolling through pages, or terminal output from build processes being a muddy blur of artifacts, or the corner case of "I work for Youtube and I need to be able to examine 4K streams to determine whether changes have resulted in a degraded experience" which is a very real job and one that becomes impossible when you pass their lovingly crafted optimisations through whatever codec your remote desktop protocol has decided to pick based on some random guesses about the local network, and look everyone is going to have a bad time.

The browser experience. As mentioned before, you'll have local browsers and remote browsers. Do they have the same security policy? Who knows! Are all the third party services you depend on going to be ok with the same user being logged in from two different IPs simultaneously because they lost track of which browser they had an open session in? Who knows! Are your users going to become frustrated? Who knows oh wait no I know the answer to this one, it's "yes".

Accessibility! More of your users than you expect rely on various accessibility interfaces, be those mechanisms for increasing contrast, screen magnifiers, text-to-speech, speech-to-text, alternative input mechanisms and so on. And you probably don't know this, but most of these mechanisms involve having accessibility software be able to introspect the UI of applications in order to provide appropriate input or expose available options and the like. So, I'm running a local text-to-speech agent. How does it know what's happening in the remote VM? It doesn't because it's just getting an a/v stream, so you need to run another accessibility stack inside the remote VM and the two of them are unaware of each others existence and this works just as badly as you'd think. Alternative input mechanism? Good fucking luck with that, you're at best going to fall back to "Send synthesized keyboard inputs" and that is nowhere near as good as "Set the contents of this text box to this unicode string" and yeah I used to work on accessibility software maybe you can tell. And how is the VM going to send data to a braille output device? Anyway, good luck with the lawsuits over arbitrarily making life harder for a bunch of members of a protected class.

One of the benefits here is supposed to be a security improvement, so let's talk about WebAuthn. I'm a big fan of WebAuthn, given that it's a multi-factor authentication mechanism that actually does a good job of protecting against phishing, but if my users are running stuff inside a VM, how do I use it? If you work at Google there's a solution, but that does mean limiting yourself to Chrome Remote Desktop (there are extremely good reasons why this isn't generally available). Microsoft have apparently just specced a mechanism for doing this over RDP, but otherwise you're left doing stuff like forwarding USB over IP, and that means that your USB WebAuthn no longer works locally. It also doesn't work for any other type of WebAuthn token, such as a bluetooth device, or an Apple TouchID sensor, or any of the Windows Hello support. If you're planning on moving to WebAuthn and also planning on moving to remote VM desktops, you're going to have a bad time.

That's the stuff that comes to mind immediately. And sure, maybe each of these issues is irrelevant to most of your users. But the actual question you need to ask is what percentage of your users will hit one or more of these, because if that's more than an insignificant percentage you'll still be staffing all the teams that dealt with hardware, handling local OS installs, worrying about lost or stolen devices, and the glorious future of just being able to stop worrying about this is going to be gone and the financial benefits you promised would appear are probably not going to work out in the same way.

A lot of this falls back to the usual story of corporate IT - understand the needs of your users and whether what you're proposing actually meets them. Almost everything I've described here is a corner case, but if your company is larger than about 20 people there's a high probability that at least one person is going to fall into at least one of these corner cases. You're going to need to spend a lot of time understanding your user population to have a real understanding of what the actual costs are here, and I haven't seen anyone do that work before trying to launch this and (inevitably) going back to just giving people actual computers.

There are alternatives! Modern IDEs tend to support SSHing out to remote hosts to perform builds there, so as long as you're ok with source code being visible on laptops you can at least shift the "I need a workstation with a bunch of CPU" problem out to the cloud. The laptops are going to need to be more expensive because they're also going to need to run more software locally, but it wouldn't surprise me if this ends up being cheaper than the full-on cloud desktop experience in most cases.

Overall, the most important thing to take into account here is that your users almost certainly have more use cases than you expect, and this sort of change is going to have direct impact on the workflow of every single one of your users. Make sure you know how much that's going to be, and take that into consideration when suggesting it'll save you money.

comments

Review: The Dragon Never Sleeps, by Glen Cook

Publisher:	Night Shade Books
Copyright:	1988
Printing:	2008
ISBN:	1-59780-099-6
Format:	MOBI
Pages:	449

Canon Space is run, in a way, by the noble mercantile houses, who spread their cities, colonies, and mines through the mysterious Web that allows faster-than-light interstellar travel. The true rulers of Canon Space, though, are the Guardships: enormous, undefeatable starships run by crews who have become effectively immortal by repeated uploading and reincarnation. Or, in the case of the Deified, without reincarnation, observing, ordering, advising, and meddling from an entirely virtual existence. The Guardships have enforced the status quo for four thousand years. House Tregesser thinks they have the means to break the stranglehold of the Guardships. They have contact with Outsiders from beyond Canon Space who can provide advanced technology. They have their own cloning technology, which they use to create backup copies of their elites. And they have Lupo Provik, a quietly brilliant schemer who has devoted his life to destroying Guardships. This book was so bad. A more sensible person than I would have given up after the first hundred pages, but I was too stubborn. The stubbornness did not pay off. Sometimes I pick up an older SFF novel and I'm reminded of how much the quality bar in the field has been raised over the past twenty years. It's not entirely fair to treat The Dragon Never Sleeps as typical of 1980s science fiction: Cook is far better known for his Black Company military fantasy series, this is one of his minor novels, and it's only been intermittently in print. But I'm dubious this would have been published at all today. First, the writing is awful. It's choppy, cliched, awkward, and has no rhythm or sense of beauty. Here's a nearly random paragraph near the beginning of the book as a sample:

He hurled thunders and lightnings with renewed fury. The whole damned universe was out to frustrate him. XII Fulminata! What the hell? Was some malign force ranged against him? That was his most secret fear. That somehow someone or something was using him the way he used so many others.

(Yes, this is one of the main characters throwing a temper tantrum with a special effects machine.) In a book of 450 pages, there are 151 chapters, and most chapters switch viewpoint characters. Most of them also end with a question or some vaguely foreboding sentence to try to build tension, and while I'm willing to admit that sometimes works when used sparingly, every three pages is not sparingly. This book is also weirdly empty of description for its size. We get a few set pieces, a few battles, and a sentence or two of physical description of most characters when they're first introduced, but it's astonishing how little of a mental image I had of this universe after reading the whole book. Cook probably describes a Guardship at some point in this book, but if he does, it completely failed to stick in my memory. There are aliens that everyone recognizes as aliens, so presumably they look different than humans, but for most of them I have no idea how. Very belatedly we're told one important species (which never gets a name) has a distinctive smell. That's about it. Instead, nearly the whole book is dialogue and scheming. It's clear that Cook is intending to write a story of schemes and counter-schemes and jousting between brilliant characters. This can work if the dialogue is sufficiently sharp and snappy to carry the story. It is not.

"What mischief have you been up to, Kez Maefele?" "Staying alive in a hostile universe." "You've had more than your share of luck." "Perhaps luck had nothing to do with it, WarAvocat. Till now." "Luck has run out. The Ku Question has run its course. The symbol is about to receive its final blow."

There are hundreds of pages of this sort of thing. The setting is at least intriguing, if not stunningly original. There are immortal warships oppressing human space, mysterious Outsiders, great house politics, and an essentially immortal alien warrior who ends up carrying most of the story. That's material for a good space opera if the reader slowly learns the shape of the universe, its history, and its landmarks and political factions. Or the author can decline to explain any of that. I suppose that's also a choice. Here are some things that you may have been curious about after reading my summary, and which I'm still curious about after having finished the book: What laws do the Guardships impose and what's the philosophy behind those laws? How does the economic system work? Who built the Guardships originally, and how? How do the humans outside of Canon Space live? Who are the Ku? Why did they start fighting the humans? How many other aliens are there? What do they think of this? How does the Canon government work? How have the Guardships remained technologically superior for four thousand years? Even where the reader gets a partial explanation, such as what Web is and how it was built, it's an unimportant aside that's largely devoid of a sense of wonder. The one piece of world-building that this book is interested in is the individual Guardships and the different ways in which they've handled millennia of self-contained patrol, and even there we only get to see a few of them. There is a plot with appropriately epic scope, but even that is undermined by the odd pacing. Five, ten, or fifty years sometimes goes by in a sentence. A war starts, with apparently enormous implications for Canon Space, and then we learn that it continues for years without warranting narrative comment. This is done without transitions and without signposts for the reader; it's just another sentence in the narration, mixed in with the rhetorical questions and clumsy foreshadowing. I would like to tell you that at least the book has a satisfying ending that resolves the plot conflict that it finally reveals to the reader, but I had a hard time understanding why the ending even mattered. The plot was so difficult to follow that I'm sure I missed something, but it's not difficult to follow in the fun way that would make me want to re-read it. It's difficult to follow because Cook doesn't seem able to explain the plot in his head to the reader in any coherent form. I think the status quo was slightly disrupted? Maybe? Also, I no longer care. Oh, and there's a gene-engineered sex slave in this book, who various male characters are very protective and possessive of, who never develops much of a personality, and who has no noticeable impact on the plot despite being a major character. Yay. This was one of the worst books I've read in a long time. In retrospect, it was an awful place to start with Glen Cook. Hopefully his better-known works are also better-written, but I can't say I feel that inspired to find out. Rating: 2 out of 10

Focus This month I didn't have any particular focus. I just worked on issues in my info bubble.

Changes

halibut: add documentation generator metadata

mpv-mpris: fix tests

duck: obsolete site indicators

devscripts: fix example, add experimental pseudo-excuses

dpkg-repack: show dpkg-deb cmd

Debian QA services: add experimental pseudo-excuses, improve excuses page

Debian usertags: fixed ports, lintian usertags

Debian package uploads: mpv-mpris backport

Debian wiki pages: ArchitectureSpecificsMemo, DebianArt/Themes/Emerald, DebianDesktop/Artwork (Bookworm), DebianLogo, DeveloperNews, FPGA, Gnome, HomeAssistant, InstructionSelection (1 2), LTS, PackageKit, PipeWire, Salsa/support, Services, ServicesHosting, SIMDEverywhere, SimpleBackportCreation, spotify, SystemBuildTools, ThomasChung, UsingSymbolsFiles, ZRam, Zswap

Libreplanet wiki pages: Group:Free_Software_Foundation/Ideas

FOSSjobs wiki pages: Resources

Wikipedia: Message-ID

Issues

Conffile removal in dkms

Features in UDD, virtual-fido

Security hardening in open-in-mpv

Packaging needed for prr, libredirect, wayback-machine-webextension

Underlinking in libgrpc

Data import problem in UDD

HTML injection in a conversion utility (sent privately)

Review

Debian wiki: RecentChanges for the month

Debian BTS usertags: changes for the month

Debian screenshots:

approved apticron-systemd argyll chromium-browser coreutils e2fsprogs exuberant-ctags firefox gnome-flashback gnome-recipes gparted initramfs-tools kdocker kleopatra latte-dock mac-robber mail-expire mgba-qt mount parolottero-data-us plasma-widget-folderview reglookup stockfish sxmo-utils uuid-runtime yoshimi

rejected weboob-qt/quake (politics), pass (baby photo), hylafax-client/libc6/ (photo of broken screen), aptitude (screenshots website), apt-file (NSFW photo), synaesthesia (meme image), kde-full (photo of human), ubuntustudio-menu (too small), tesseract-ocr-eng (identification card), mpv (proprietary video), g++-9/python3-ldap (random logo), synaptic (logo), openjdk-8-jre (NSFW, mobile browser), libreoffice-base-core/librtmp1/audacity (Android/iOS app), virtualbox-guest-additions-iso (ISO contents not interface), weboob-qt (another package), freecell-solver-bin (accidentally)

Administration

Debian QA services: deploy changes

Debian wiki: approve accounts

Communication

Respond to queries from Debian users and contributors on the mailing lists and IRC

Sponsors All work was done on a volunteer basis.

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!

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.

comments

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.

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).

HistoryThe 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

mysecureshellThe 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-scsThe 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-scsThe 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 scriptThe 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 scriptThe 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 scriptThe 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 objectsThe 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.yamlThe 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.yamlThe 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.yamlThe 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.yamlTo 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.yamlTo 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

DeploymentTo 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 uploadsAs 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

We connect to the sftp service on the forwarded port with the scs user.
We put a file we have created on the host on the directory.
We do a hard link of the uploaded file.
We put a second copy of the file we created locally.
On the file list we can see that the two first files have two hardlinks

File retrievalsIf 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 containerTo 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
This command creates the cronjob object.
This checks the pods with our cronjob label, we interrupt it once we see that the first run has been completed.
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).
After waiting a little bit we check the pods executed again to get the name of the latest one.
The log now shows that nothing was done.
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
Here we create the webhook-job-secrets secret that contains the s3sync.json file.
This command runs the job.
Checking the label cronjob=s3sync we get the Pods executed by the job.
Here we print the logs of the completed job.
Once we are finished we remove the Job.
And also the secret.

Final remarksThis 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.

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

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 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 17^th (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.

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.

ninlive.com recordings for Friday
setlist.fm page for Friday (nerdy song stats etc)

Saturday 18^th (rain)

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

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

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.

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.

comments

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.

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?

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.

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.

comments

Search Results: "ana"

19 October 2022

Petter Reinholdtsen: Managing and using ONVIF IP cameras with Linux

17 October 2022

Jeremy Bicha: Ubuntu bug fix anniversary

16 October 2022

Vincent Fourmond: Tutorial: analysis of multiwavelength fast kinetics data

kpcyrd: updlockfiles: Manage lockfiles in PKGBUILDs for upstreams that don't ship them

Thanks This work is currently crowd-funded on github sponsors. I d like to thank @SantiagoTorres, @repi and @rgacogne for their support in particular.

10 October 2022

Ian Jackson: Skipping releases when upgrading Debian systems

Joachim Breitner: rec-def: Minesweeper case study

9 October 2022

Sergio Talens-Oliag: Shared networking for Virtual Machines and Containers

Warning: To use a separate file with `ifupdown` make sure that `/etc/network/interfaces` contains the line:
`source /etc/network/interfaces.d/*`
or add its contents to `/etc/network/interfaces` directly, if you prefer.

7 October 2022

Reproducible Builds: Reproducible Builds in September 2022

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

6 October 2022

Matthew Garrett: Cloud desktops aren't as good as you'd think

4 October 2022

Abhijith PA: Laptop refreshment

Abhijith PA

Hello, I'm Abhijith. A Free Software enthusiast.

Laptop refreshment

Abhijith PA

Hello, I'm Abhijith. A Free Software enthusiast.

Trip to misty mountains in Munnar

File retrievalsIf 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`

Final remarksThis 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.

22 September 2022

Jonathan Dowland: Nine Inch Nails, Cornwall, June

20 September 2022

Matthew Garrett: Handling WebAuthn over remote SSH connections

19 September 2022

Antoine Beaupr : Looking at Wayland terminal emulators

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.

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.

Matthew Garrett: Bring Your Own Disaster

Search Results: "ana"

19 October 2022

17 October 2022

16 October 2022

Thanks This work is currently crowd-funded on github sponsors. I d like to thank @SantiagoTorres, @repi and @rgacogne for their support in particular.

10 October 2022

9 October 2022

Warning: To use a separate file with ifupdown make sure that /etc/network/interfaces contains the line: source /etc/network/interfaces.d/* or add its contents to /etc/network/interfaces directly, if you prefer.

7 October 2022

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

6 October 2022

4 October 2022

3 October 2022

Focus This month I didn't have any particular focus. I just worked on issues in my info bubble.

Issues Conffile removal in dkms Features in UDD, virtual-fido Security hardening in open-in-mpv Packaging needed for prr, libredirect, wayback-machine-webextension Underlinking in libgrpc Data import problem in UDD HTML injection in a conversion utility (sent privately)

Administration Debian QA services: deploy changes Debian wiki: approve accounts

Communication Respond to queries from Debian users and contributors on the mailing lists and IRC

Sponsors All work was done on a volunteer basis.

29 September 2022

28 September 2022

25 September 2022

File retrievalsIf 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

Final remarksThis 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.

22 September 2022

20 September 2022

19 September 2022

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.

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.

Warning: To use a separate file with `ifupdown` make sure that `/etc/network/interfaces` contains the line:
`source /etc/network/interfaces.d/*`
or add its contents to `/etc/network/interfaces` directly, if you prefer.

Issues

Conffile removal in dkms

Features in UDD, virtual-fido

Security hardening in open-in-mpv

Packaging needed for prr, libredirect, wayback-machine-webextension

Underlinking in libgrpc

Data import problem in UDD

HTML injection in a conversion utility (sent privately)

Administration

Debian QA services: deploy changes

Debian wiki: approve accounts

Communication

Respond to queries from Debian users and contributors on the mailing lists and IRC

File retrievalsIf 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`