Search Results: "ch"

26 January 2025

Dirk Eddelbuettel: RcppBDT 0.2.7 on CRAN: Maintenance

Another minor maintenance release for the RcppBDT package is now on CRAN. The RcppBDT package is an early adopter of Rcpp and was one of the first packages utilizing Boost and its Date_Time library. The now more widely-used package anytime is a direct descentant of RcppBDT. This release follows the recent updates of other package updating their C++ compilation standard along with other standard package updates. No feature or interface changes. The NEWS entry follows:

Changes in version 0.2.7 (2025-01-25)
  • The package no longer sets a C++ compilation standard
  • Package infrastructure, documentation and continuous integration support have been updated
  • Several manual pages now have package anchors for the code link
  • A demo/ file has been move to inst/examples/

Courtesy of my CRANberries, there is also a diffstat report for this release. For questions, suggestions, or issues please use the issue tracker at the GitHub repo.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can now sponsor me at GitHub.

25 January 2025

Steve Kemp: The CP/M emulator now works better!

I keep saying I'm "done" with my CP/M emulator, but then I keep overhauling it in significant ways. Today is no exception. In the past the emulator used breakpoints to detect when calls to the system BIOS, or BDOS, were made. That was possible because the BIOS and BDOS entry points are at predictable locations. For example a well-behaved program might make a system call with code like this: 
    LD A,42
    LD C,4
    CALL 0x0005
So setting a breakpoint on 0x0005 would let you detect a system-call was being made, inspect the registers to see which system-call was being made and then carry out the appropriate action in your emulator before returning control back to the program. Unfortunately some binaries patch the RAM, changing the contents of the entry points, or changing internal jump-tables, etc. The end result is that sometimes code running at the fixed addresses is not your BIOS at all, but something else. By trapping/faulting/catching execution here you break things, badly. So today's new release fixes that! No more breakpoints. Instead we deploy a "real BDOS" in RAM that will route system-calls to our host emulator via a clever trick. For BDOS functions the C-register will contain the system call to operate, our complete BDOS implementation is: 
    OUT (C),C
    RET
The host program can catch writes to output ports, and will know that "OUT (3), 3" means "Invoke system call #3", for example. This means binary patches to entry-points, or any internal jump-tables won't confuse things and so long as control eventually reaches my BIOS or BDOS code areas things will work. I also added a new console-input driver, since I have a notion of pluggable input and output devices, which just reads input from a file. Now I can prove that my code works. Pass the following file to the input-driver and we have automated testing: 
A:
ERA HELLO.COM
ERA HELLO.HEX
ERA HELLO.PRN
hello
ASM HELLO
LOAD HELLO
DDT HELLO.com
t
t
t
t
t
t
t
t
t
C-c
EXIT
Here we: I can test the output and confirm there are no regressions. Neat. Anyway new release, today. Happy.

Bits from Debian: Infomaniak Platinum Sponsor of DebConf25

infomaniaklogo We are pleased to announce that Infomaniak has committed to sponsor DebConf25 as a Platinum Sponsor. Infomaniak is Switzerland s leading developer of Web technologies. With operations all over Europe and based exclusively in Switzerland, the company designs and manages its own data centers powered by 100% renewable energy, and develops all its solutions locally, without outsourcing. With millions of users and the trust of public and private organizations across Europe - such as RTBF, the United Nations, central banks, over 3,000 radio and TV stations, as well as numerous cities and security bodies - Infomaniak stands for sovereign, sustainable and independent digital technology. The company offers a complete suite of collaborative tools, cloud hosting, streaming, marketing and events solutions, while being owned by its employees and self-financed exclusively by its customers. With this commitment as Platinum Sponsor, Infomaniak is contributing to the Debian annual Developers' conference, directly supporting the progress of Debian and Free Software. Infomaniak contributes to strengthen the community that collaborates on Debian projects from all around the world throughout all of the year. Thank you very much, Infomaniak, for your support of DebConf25! Become a sponsor too! DebConf25 will take place from 14th to July 20th 2025 in Brest, France, and will be preceded by DebCamp, from 7th to 13th July 2025. DebConf25 is accepting sponsors! Interested companies and organizations should contact the DebConf team through sponsors@debconf.org, or visit the DebConf25 website at https://debconf25.debconf.org/sponsors/become-a-sponsor/.

24 January 2025

Scarlett Gately Moore: KDE: Snaps bug fixes and Kubuntu: Noble updates

Fixed a major crash bug in our apps that use webengine, I also went ahead and updated these to core24 https://bugs.launchpad.net/snapd/+bug/2095418 andhttps://bugs.kde.org/show_bug.cgi?id=498663 Fixed okular
Can t import certificates to digitally sign in Okular https://bugs.kde.org/show_bug.cgi?id=498558 Can t open files https://bugs.kde.org/show_bug.cgi?id=421987 and https://bugs.kde.org/show_bug.cgi?id=415711 Skanpage won t launch https://bugs.kde.org/show_bug.cgi?id=493847 in edge please help test. Ghostwriter https://bugs.kde.org/show_bug.cgi?id=481258
Kalm - Breathing techniques
New KDE Snaps! Kalm Breathing techniques
Telly-skout Display TV guides Kubuntu: Plasma 5.27.12 has been uploaded to archive proposed and should make the .2 release! I hate asking but I am unemployable with this broken arm fiasco. If you could spare anything it would be appreciated! https://gofund.me/573cc38e

Jonathan Dowland: FOSDEM 2025

I'm going to FOSDEM 2025! As usual, I'll be in the Java Devroom for most of that day, which this time around is Saturday. Please recommend me any talks! This is my shortlist so far:

Sam Hartman: Feeling Targeted: Executive Order Ending Wasteful DEIA Efforts

As most here know, I m totally blind. One of my roles involves a contract for the US Government, under which I have a government email account. The department recently received a message talking about our work to end, to the maximum extend permitted by law, all diversity, equity, inclusion, and accessibility efforts in the government in accordance with the recently signed executive order. We are all reminded that if we timely identify the contracts and positions that are related to these efforts, there will be no consequences. There are a lot of times in my life when I have felt marginalized frustrated and angry that people weren t interested in working with me to make the small changes that would help me fit in. As an example with this government job, I asked to have access to a screen reader so that I could use my computer. My preferred adaptive software was not approved, even though it was thousands of dollars cheaper than the option the government wanted and could have been installed instantly rather than waiting for a multi-week ordering process. When the screen reader eventually became available, the government-provided installer was not accessible: a blind person could not use it. When I asked for help, the government added an additional multi-week delay because they weren t sure that the license management technology for the software they had chosen met the government s security and privacy policies. Which is to say that even with people actively working toward accessibility, sharing a commitment that accessibility is important, we have a lot of work to do. I feel very targeted at the current time. Now we are removing as many of the resources that help me be effective and feel welcome as we can. Talking about the lack of consequences now is just a way to remind everyone that there will be consequences later and get the fear going. The witch hunt is coming, and if people do a good enough job of turning in all the people who could help me feel welcome, they won t face consequences. Yes, I understand that the Americans with Disabilities act is still law, but its effectiveness will be very different in a climate where you need to eliminate accessibility positions to avoid consequences than in a climate where accessibility is a goal.

comment count unavailable comments

Reproducible Builds (diffoscope): diffoscope 286 released

The diffoscope maintainers are pleased to announce the release of diffoscope version 286. This version includes the following changes: 
[ Chris Lamb ]
* Bug fixes:
  - When passing files on the command line, don't call specialize(..) before
    we've checked that the files are identical. In the worst case, this was
    resulting in spinning up binwalk and extracting two entire filesystem
    images merely to confirm that they were indeed filesystem images..
    before simply concluding that they were identical anyway.
  - Do not exit with a traceback if paths are inaccessible, either directly,
    via symbolic links or within a directory. (Closes: #1065498)
  - Correctly identify changes to only the line-endings of files; don't mark
    them as "Ordering differences only".
  - Use the "surrogateescape" mechanism of str. decode,encode  to avoid a
    UnicodeDecodeError and crash when decoding zipinfo output that is not
    valid UTF-8. (Closes: #1093484)
* Testsuite changes:
  - Don't mangle newlines when opening test fixtures; we want them untouched.
  - Move to assert_diff in test_text.py.
* Misc:
  - Remove unnecessary return value from check_for_ordering_differences in
    the Difference class.
  - Drop an unused function in iso9600.py
  - Inline a call/check of Config().force_details; no need for an additional
    variable.
You find out more by visiting the project homepage.

23 January 2025

Dirk Eddelbuettel: qlcal 0.0.14 on CRAN: Calendar Updates

The fourteenth release of the qlcal package arrivied at CRAN today, following the QuantLib 1.37 release two days ago. qlcal delivers the calendaring parts of QuantLib. It is provided (for the R package) as a set of included files, so the package is self-contained and does not depend on an external QuantLib library (which can be demanding to build). qlcal covers over sixty country / market calendars and can compute holiday lists, its complement (i.e. business day lists) and much more. Examples are in the README at the repository, the package page, and course at the CRAN package page. This releases synchronizes qlcal with the QuantLib release 1.37 (made this week), and moves a demo/ file to examples/.

Changes in version 0.0.14 (2025-01-23)
  • Synchronized with QuantLib 1.37 released two days ago
  • Calendar updates for United States and New Zealand
  • The demo/ file is now in inst/examples/

This update includes the inclusion of the January 9, 2025, holiday for the memorial of President Carter that was observed at the NYSE and shown by the allUScalendars.R example: 
edd@rob:~/git/qlcal-r/inst/examples(master)$ Rscript allUScalendars.R 
           LiborImpact NYSE GovernmentBond NERC FederalReserve SOFR
2025-01-01        TRUE TRUE           TRUE TRUE           TRUE TRUE
2025-01-09          NA TRUE             NA   NA             NA   NA
2025-01-20        TRUE TRUE           TRUE   NA           TRUE TRUE
2025-02-17        TRUE TRUE           TRUE   NA           TRUE TRUE
2025-04-18          NA TRUE           TRUE   NA             NA TRUE
2025-05-26        TRUE TRUE           TRUE TRUE           TRUE TRUE
2025-06-19        TRUE TRUE           TRUE   NA           TRUE TRUE
2025-07-04        TRUE TRUE           TRUE TRUE           TRUE TRUE
2025-09-01        TRUE TRUE           TRUE TRUE           TRUE TRUE
2025-10-13        TRUE   NA           TRUE   NA           TRUE TRUE
2025-11-11        TRUE   NA           TRUE   NA           TRUE TRUE
2025-11-27        TRUE TRUE           TRUE TRUE           TRUE TRUE
2025-12-25        TRUE TRUE           TRUE TRUE           TRUE TRUE
edd@rob:~/git/qlcal-r/inst/examples(master)$
Courtesy of my CRANberries, there is a diffstat report for this release. See the project page and package documentation for more details, and more examples. If you like this or other open-source work I do, you can sponsor me at GitHub.

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

Sergio Talens-Oliag: Ghostty Terminal Emulator

For a long time I ve been using the Terminator terminal emulator on Linux machines, but last week I read a LWN article about a new emulator called Ghostty that looked interesting and I decided to give it a try. The author sells it as a fast, feature-rich and cross-platform terminal emulator that follows the zero configuration philosophy.

Installation and configurationI installed the debian package for Ubuntu 24.04 from the ghostty-ubuntu project and started playing with it. The first thing I noticed is that the zero configuration part is true; I was able to use the terminal without a configuration file, although I created one to change the theme and the font size, but other than that it worked OK for me; my $HOME/.config/ghostty/config file is as simple as: 
font-size=14
theme=/usr/share/ghostty/themes/iTerm2 Solarized Light

Starting the terminal maximizedAfter playing a little bit with the terminal I was turned off by the fact that there was no option to start it maximized, but is seemed to me that someone should have asked for the feature, or, if not, I could ask for it. I did a quick search on the project and I found out that there was a merged PR that added the option, so I downloaded the source code, installed Zig and built the program on my machine. As the change is going to be included on the next version on the package I replaced the binary with my version and started playing with the terminal.

Accessing remote machinesThe first thing I noticed was that when logging into remote machines using ssh the terminal variable was not known, but on the help section of the project documentation there was an entry about how to fix it copying the terminfo configuration to remote machines, it is as simple as running the following: 
infocmp -x   ssh YOUR-SERVER -- tic -x -

Dead keys on UbuntuWith that sorted out everything looked good to me until I tried to add an accented character when editing a file and the terminal stopped working. Again, I looked at the project issues and found one that matched what was happening to me, and it remembered me about one of the best things about actively maintained open source software. It turns out that the issue is related to a bug on ibus, but other terminals were working right, so the ghostty developer was already working on a fix on the way the terminal handles the keyboard input on GTK, so I subscribed to the issue and stopped using ghostty until there was something new to try again (I use an Spanish keyboard map and I can t use a terminal that does not support dead keys). Yesterday I saw some messages about things being almost fixed, so I pulled the latest changes on my cloned repository, compiled it and writing accented characters works now, there is a small issue with the cursor (the dead key pressed is left on the block cursor unless you change the window focus), but that is something manageable for me.

ConclusionI think that ghostty is a good terminal emulator and I m going to keep using it on my laptop unless I find something annoying that I can t work with (i hope that the cursor issue will be fixed soon and I can live with it as the only thing I need to do to recover from it is changing the widow focus, and that can be done really quickly using keyboard shortcuts). As it is actively maintained and the developer seems to be quite active I don t expect problems and is nice to play with new things from time to time.

22 January 2025

Jonathan McDowell: Christmas Movies

I watch a lot of films. Since completing the IMDB Top 250 back in 2016 I ve kept an eye on it, and while I don t go out of my way to watch the films that newly appear in it I generally sit at over 240 watched. I should note I don t consider myself a film buff/critic, however. I watch things for enjoyment, and a lot of the time that s kicking back and relaxing and disengaging my brain. So I don t get into writing reviews, just high level lists of things I ve watched, sometimes with a few comments. With that in mind, let s talk about Christmas movies. Yes, I appreciate it s the end of January, but generally during December we watch things that have some sort of Christmas theme. New ones if we can find them, but also some of what we consider classics . This almost always starts with Scrooged after we ve put up the tree. I don t always like Bill Murray (I couldn t watch The Life Aquatic with Steve Zissou and I think Lost in Translation is overrated), but he s in a bunch of things I really like, and Scrooged is one of those. I don t care where you sit on whether Die Hard is a Christmas movie or not, it s a good movie and therefore regularly gets a December watch. Die Hard 2 also fits into that category of sequel at least as good as the original , though Helen doesn t agree. We watched it anyway, and I finally made the connection between the William Sadler hotel scene and Michael Rooker s in Mallrats. It turns out I m a Richard Curtis fan. Love Actually has not aged well; most times I watch it I find something new questionable about it, and I always end up hating Alan Rickman for cheating on Emma Thompson, but I do like watching it. He had a new one, That Christmas, out this year, so we watched it as well. Another new-to-us film this year was Spirited. I generally like Ryan Reynolds, and Will Ferrell is good as long as he s not too overboard, so I had high hopes. I enjoyed it, but for some reason not as much as I d expected, and I doubt it s getting added to the regular watch list. Larry doesn t generally like watching full length films, but he (and we), enjoyed The Grinch, which I actually hadn t seen before. He s not as fussed on The Muppet Christmas Carol, but we watched it every year, generally on Christmas or Boxing Day. Favourite thing I saw on the Fediverse in December was Do you know there s a book of The Muppet Christmas Carol, and they don t mention that there s muppets in it once? There are a various other light hearted Christmas films we regularly watch. This year included The Holiday (I have so many issues with even just the practicalities of a short notice house swap), and Last Christmas (lots of George Michael music, what s not to love? Also it was only on this watch through that we realised the lead character is the Mother of Dragons). We started, but could not finish, Carry On. I saw it described somewhere as copaganda, and that feels accurate. It does not accurately reflect any of my interactions with TSA at airports, especially during busy periods. Things we didn t watch this year, but are regularly in the mix, include Fatman, Violent Night (looking forward to the sequel, hopefully this year), and Lethal Weapon. Klaus is kinda at the other end of the spectrum, but very touching, and we ve watched it a couple of years now. Given what we seem to like, any suggestions for other films to add? It s nice to have enough in the mix that we get some variety every year.

21 January 2025

Dirk Eddelbuettel: ttdo 0.0.10 on CRAN: Small Extension

A new minor release of our ttdo package arrived on CRAN a few days ago. The ttdo package extends the excellent (and very minimal / zero depends) unit testing package tinytest by Mark van der Loo with the very clever and well-done diffobj package by Brodie Gaslam to give us test results with visual diffs (as shown in the screenshot below) which seemingly is so compelling an idea that it eventually got copied by another package which shall remain unnamed And as of this release, we also support visual diffs as provided by tinysnapshot by Vincent Arel-Bundock. ttdo screenshot This release chiefly adds support for visual diff plots. As we extend tinytest for use in the R autograder we maintain and deploy within the lovely PrairieLearn framework, we need to encode the diffplot that has been produced by the autograder (commonly in a separate Docker process) to communicate it back to the controlling (Docker also) instance of PrairieLearn. We also did the usual bits of package maintenance keeping badges, URLs, continuous integration and minor R coding standards current. As usual, the NEWS entry follows.

Changes in ttdo version 0.0.10 (2025-01-21)
  • Regular packaging updates to badges and continuous integration setup
  • Add support for a 'visual difference' taking advantage of a tinysnapshot feature returning a ttvd-typed result
  • Added (versioned) dependency on tinysnapshot (to also get the plot 'style' enhancement in the most recent version) and base64enc
  • Return ttdo-typed result if diffobj-printed result is returned
  • Ensure all package-documentation links in manual page have anchors to the package

Courtesy of my CRANberries, there is also a diffstat report for this release. For questions, suggestions, or issues please use the issue tracker at the GitHub repo.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can now sponsor me at GitHub.

Ravi Dwivedi: The Arduous Luxembourg Visa Process

In 2024, I was sponsored by The Document Foundation (TDF) to attend the LibreOffice annual conference in Luxembourg from the 10th to the 12th of October. Being an Indian passport holder, I needed a visa to visit Luxembourg. However, due to my Kenya trip coming up in September, I ran into a dilemma: whether to apply before or after the Kenya trip. To obtain a visa, I needed to submit my application with VFS Global (and not with the Luxembourg embassy directly). Therefore, I checked the VFS website for information on processing time, which says:
As a rule, the processing time of an admissible Schengen visa application should not exceed 15 calendar days (from the date the application is received at the Embassy).
It also mentions:
If the application is received less than 15 calendar days before the intended travel date, the Embassy can deem your application inadmissible. If so, your visa application will not be processed by the Embassy and the application will be sent back to VFS along with the passport.
If I applied for the Luxembourg visa before my trip, I would run the risk of not getting my passport back in time, and therefore missing my Kenya flight. On the other hand, if I waited until after returning from Kenya, I would run afoul of the aforementioned 15 working days needed by the embassy to process my application. I had previously applied for a Schengen visa for Austria, which was completed in 7 working days. My friends who had been to France told me they got their visa decision within a week. So, I compared Luxembourg s application numbers with those of other Schengen countries. In 2023, Luxembourg received 3,090 applications from India, while Austria received 39,558, Italy received 52,332 and France received 176,237. Since Luxembourg receives a far fewer number of applications, I expected the process to be quick. Therefore, I submitted my visa application with VFS Global in Delhi on the 5th of August, giving the embassy a month with 18 working days before my Kenya trip. However, I didn t mention my Kenya trip in the Luxembourg visa application. For reference, here is a list of documents I submitted: I submitted flight reservations instead of flight tickets . It is because, in case of visa rejection, I would have lost a significant amount of money if I booked confirmed flight tickets. The embassy also recommends the same. After the submission of documents, my fingerprints were taken. The expenses for the visa application were as follows:
Service Description Amount (INR)
Visa Fee 8,114
VFS Global Fee 1,763
Courier 800
Total 10,677
Going by the emails sent by VFS, my application reached the Luxembourg embassy the next day. Fast-forward to the 27th of August 14th day of my visa application. I had already booked my flight ticket to Nairobi for the 4th of September, but my passport was still with the Luxembourg embassy, and I hadn t heard back. In addition, I also obtained Kenya s eTA and got vaccinated for Yellow Fever, a requirement to travel to Kenya. In order to check on my application status, I gave the embassy a phone call, but missed their calling window, which was easy to miss since it was only 1 hour - 12:00 to 1:00 PM. So, I dropped them an email explaining my situation. At this point, I was already wondering whether to cancel the Kenya trip or the Luxembourg one, if I had to choose. After not getting a response to my email, I called them again the next day. The embassy told me they would look into it and asked me to send my flight tickets over email. One week to go before my flight now. I followed up with the embassy on the 30th by a phone call, and the person who picked up the call told me that my request had already been forwarded to the concerned department and is under process. They asked me to follow up on Monday, 2nd September. During the visa process, I was in touch with three other Indian attendees.1 In the meantime, I got to know that all of them had applied for a Luxembourg visa by the end of the month of August. Back to our story, over the next two days, the embassy closed for the weekend. I began weighing my options. On one hand, I could cancel the Kenya trip and hope that Luxembourg goes through. Even then, Luxembourg wasn t guaranteed as the visa could get rejected, so I might have ended up missing both the trips. On the other hand, I could cancel the Luxembourg visa application and at least be sure of going to Kenya. However, I thought it would make Luxembourg very unlikely because it didn t leave 15 working days for the embassy to process my visa after returning from Kenya. I also badly wanted to attend the LibreOffice conference because I couldn t make it two years ago. Therefore, I chose not to cancel my Luxembourg visa application. I checked with my travel agent and learned that I could cancel my Nairobi flight before September 4th for a cancelation fee of approximately 7,000 INR. On the 2nd of September, I was a bit frustrated because I hadn t heard anything from the embassy regarding my request. Therefore, I called the embassy again. They assured me that they would arrange a call for me from the concerned department that day, which I did receive later that evening. During the call, they offered to return my passport via VFS the next day and asked me to resubmit it after returning from Kenya. I immediately accepted the offer and was overjoyed, as it would enable me to take my flight to Nairobi without canceling my Luxembourg visa application. However, I didn t have the offer in writing, so it wasn t clear to me how I would collect my passport from VFS. The next day, I would receive it when I would be on my way to VFS in the form of an email from the embassy which read:
Dear Mr. Dwivedi, We acknowledge the receipt of your email. As you requested, we are returning your passport exceptionally through VFS, you can collect it directly from VFS Delhi Center between 14:00-17:00 hrs, 03 Sep 2024. Kindly bring the printout of this email along with your VFS deposit receipt and Original ID proof. Once you are back from your trip, you can redeposit the passport with VFS Luxembourg for our processing. With best regards,
Consular Section GRAND DUCHY OF LUXEMBOURG
Embassy in New Delhi
I took a printout of the email and submitted it to VFS to get my passport. This seemed like a miracle - just when I lost all hope of making it to my Kenya flight and was mentally preparing myself to miss it, I got my passport back exceptionally and now I had to mentally prepare again for Kenya. I had never heard of an embassy returning passport before completing the visa process before. The next day, I took my flight to Nairobi as planned. In case you are interested, I have written two blog posts on my Kenya trip - one on the OpenStreetMap conference in Nairobi and the other on my travel experience in Kenya. After returning from Kenya, I resubmitted my passport on the 17th of September. Fast-forward to the 25th of September; I didn t hear anything from the embassy about my application process. So, I checked with TDF to see whether the embassy reached out to them. They told me they confirmed my participation and my hotel booking to the visa authorities on the 19th of September (6 days ago). I was wondering what was taking so long after the verification. On the 1st of October, I received a phone call from the Luxembourg embassy, which turned out to be a surprise interview. They asked me about my work, my income, how I came to know about the conference, whether I had been to Europe before, etc. The call lasted around 10 minutes. At this point, my travel date - 8th of October - was just two working days away as the 2nd of October was off due to Gandhi Jayanti and 5th and 6th October were weekends, leaving only the 3rd and the 4th. I am not sure why the embassy saved this for the last moment, even though I submitted my application 2 months ago. I also got to know that one of the other Indian attendees missed the call due to being in their college lab, where he was not allowed to take phone calls. Therefore, I recommend that the embassy agree on a time slot for the interview call beforehand. Visa decisions for all the above-mentioned Indian attendees were sent by the embassy on the 4th of October, and I received mine on the 5th. For my travel date of 8th October, this was literally the last moment the embassy could send my visa. The parcel contained my passport and a letter. The visa was attached to a page in the passport. I was happy that my visa had been approved. However, the timing made my task challenging. The enclosed letter stated:
Subject: Your Visa Application for Luxembourg
Dear Applicant, We would like to inform you that a Schengen visa has been granted for the 8-day duration from 08/10/2024 to 30/10/2024 for conference purposes in Luxembourg. You are requested to report back to the Embassy of Luxembourg in New Delhi through an email (email address redacted) after your return with the following documents:
  • Immigration Stamps (Entry and Exit of Schengen Area)
  • Restaurant Bills
  • Shopping/Hotel/Accommodation bills
Failure to report to the Embassy after your return will be taken into consideration for any further visa applications.
I understand the embassy wanting to ensure my entry and exit from the Schengen area during the visa validity period, but found the demand for sending shopping bills excessive. Further, not everyone was as lucky as I was as it took a couple of days for one of the Indian attendees to receive their visa, delaying their plan. Another attendee had to send their father to the VFS center to collect their visa in time, rather than wait for the courier to arrive at their home. Foreign travel is complicated, especially for the citizens of countries whose passports and currencies are weak. Embassies issuing visas a day before the travel date doesn t help. For starters, a last-minute visa does not give enough time for obtaining a forex card as banks ask for the visa. Further, getting foreign currency (Euros in our case) in cash with a good exchange rate becomes difficult. As an example, for the Kenya trip, I had to get US Dollars at the airport due to the plan being finalized at the last moment, worsening the exchange rate. Back to the current case, the flight prices went up significantly compared to September, almost doubling. The choice of airlines also got narrowed, as most of the flights got booked by the time I received my visa. With all that said, I think it was still better than an arbitrary rejection. Credits: Contrapunctus, Badri, Fletcher, Benson, and Anirudh for helping with the draft of this post.
  1. Thanks to Sophie, our point of contact for the conference, for putting me in touch with them.

20 January 2025

Divine Attah-Ohiemi: Progress Report: First Half of My Outreachy Internship

Hello everyone!, I m excited to share a progress report on my Outreachy internship with the Debian community. As I reach the halfway point of this journey, I want to reflect on what I ve accomplished so far and outline my modified goals for the second half of the internship. In truth, there wasn t a strict timeline for my project migrating Debian webpage content to Hugo because the original repository contained thousands of pages. The initial goal was to develop a proof of concept for: Thanks to our daily standups, where we brainstorm and revise contributions, we ve made significant progress. The wiki documentation discussing the technical decisions taken to meet these goals is currently in progress here. During the first half of my internship, I have improved and refined my skills in several areas. I learned new Markdown syntaxes, studied and utilized Apache's mod_rewrite, and halfway studied GNU Make to use Perl scripts for processing data for dynamic content. I recommend Managing Projects with GNU Make by Robert Mecklenburg it's a great book for beginners! While I didn t get stuck on any particular goal, the most challenging aspect was adding Hugo aliases to help with Apache's multilingual content negotiation. The way the webwml repository generates multilingual content differs from debianhugo. For instance, in webwml, the structure looks like this: english/index.wml -> /index.en.html (with a symlink from index.html to index.en.html) and french/index.wml -> /index.fr.html. In contrast, debianhugo uses en/_index.md -> /index.html and fr/_index.md -> /fr/index.html. Apache's multilingual content negotiation checks for index.<user preferred lang code>.html in the current directory, which works well with webwml since all related translations are generated in the same directory. However, with debianhugo using subdirectories for languages other than English, we had to set up aliases for every other language page to be generated in the frontmatter. For example, in fr/_index.md, we added this to the front matter:
...
aliases:
  - /index.fr.html
...
This setup allows Hugo to generate multilingual HTML files in the initial home directory solely for the purpose of setting up a 301 redirect to the same page in the language subdirectory. However, if the client sets their preferred language to English, Apache content negotiation tries to find /index.en.html. If it doesn t find it, it defaults to any other language-suffixed file, which can lead to unexpected behavior. For example, if English is set as the preferred language, accessing the site may serve /index.fr.html, which then redirects to /fr/index.html. This was a significant challenge, and you can see a demo of this hosted here. If I were to start the project over, I would document every decision as I make them in the wiki, no matter how rough the documentation turns out. Waiting until the midpoint of the project to document was not a good idea. As I move into the second half of my internship, the goals we ve set include improving our project wiki documentation and continuing the migration process while enhancing the user experience of complicated sections. I m looking forward to making even more progress and sharing my journey with you all. Happy coding!

Jonathan Dowland: dsafilter 20th Anniversary

Happy 20th birthday, dsafilter! dsafilter is a mail filter I wrote two decades ago to solve a problem I had: I was dutifully subscribed to debian-security-announce to learn of new security package updates, but most were not relevant to me. The filter creates a new, summarizing mail, reporting on whether the DSA was applicable to any package installed on the system running the filter, and attached the original DSA mail for reference. Users can then choose to drop mails for packages that aren't relevant. In 2005 I'd been a Debian user for about 6 years, I'd met a few Debian developers in person and I was interested in getting involved. I started my journey to Developer later that same year. I published dsafilter, and I think I sent an announcement to debian-devel, but didn't do a great deal to socialise it, so I suspect nobody else is using it. That said, I have been for the two decades, and I still am! What's notable to me about that is that I haven't had to modify the script at all to keep up with software changes, in particular, from the interpreter. I wrote it as a Ruby script. If I had chosen Perl, it would probably be the same story, but if I'd chosen Python, there's no chance at all that it would still be working today. If it sounds interesting to you, please give it a try. I think it might be due some spring cleaning.

Dirk Eddelbuettel: RcppMsgPack 0.2.4 on CRAN: Maintenance

Another maintenance release of RcppMsgPack got onto CRAN today. MessagePack itself is an efficient binary serialization format. It lets you exchange data among multiple languages like JSON. But it is faster and smaller. Small integers are encoded into a single byte, and typical short strings require only one extra byte in addition to the strings themselves. RcppMsgPack brings both the C++ headers of MessagePack as well as clever code (in both R and C++) Travers wrote to access MsgPack-encoded objects directly from R. This is the first release in over six years, and contains mostly maintenance. One somewhat embarassing aspect is that Travers and I forgot about a PR that had been ready all this since the last release, it has now been integrated. Details follow from the NEWS file.

Changes in version 0.2.4 (2025-01-19)
  • Use Rcpp::RawVector instead of std::vector<unsigned char> saving extra copy (Travers in #16)
  • Several updates to README.md with R Journal paper, add badges, add Authors@R, add CITATION file, add repo info to DESCRIPTION
  • Update continuous integration via r-ci
  • Update to no longer require compilation standard

Courtesy of my CRANberries, there is also a diffstat report for this release. For questions, suggestions, or issues please use the [issue tracker][issue tickets] at the GitHub repo.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. If you like this or other open-source work I do, you can now sponsor me at GitHub.

19 January 2025

Fran ois Marier: Blocking comment spammers on an Ikiwiki blog

Despite comments on my ikiwiki blog being fully moderated, spammers have been increasingly posting link spam comments on my blog. While I used to use the blogspam plugin, the underlying service was likely retired circa 2017 and its public repositories are all archived. It turns out that there is a relatively simple way to drastically reduce the amount of spam submitted to the moderation queue: ban the datacentre IP addresses that spammers are using.

Looking up AS numbers It all starts by looking at the IP address of a submitted comment: From there, we can look it up using whois: 
$ whois -r 2a0b:7140:1:1:5054:ff:fe66:85c5
% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html
% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.
% Information related to '2a0b:7140:1::/48'
% Abuse contact for '2a0b:7140:1::/48' is 'abuse@servinga.com'
inet6num:       2a0b:7140:1::/48
netname:        EE-SERVINGA-2022083002
descr:          servinga.com - Estonia
geoloc:         59.4424455 24.7442221
country:        EE
org:            ORG-SG262-RIPE
mnt-domains:    HANNASKE-MNT
admin-c:        CL8090-RIPE
tech-c:         CL8090-RIPE
status:         ASSIGNED
mnt-by:         MNT-SERVINGA
created:        2020-02-18T11:12:49Z
last-modified:  2024-12-04T12:07:26Z
source:         RIPE
% Information related to '2a0b:7140:1::/48AS207408'
route6:         2a0b:7140:1::/48
descr:          servinga.com - Estonia
origin:         AS207408
mnt-by:         MNT-SERVINGA
created:        2020-02-18T11:18:11Z
last-modified:  2024-12-11T23:09:19Z
source:         RIPE
% This query was served by the RIPE Database Query Service version 1.114 (SHETLAND)
The important bit here is this line: 
origin:         AS207408
which referts to Autonomous System 207408, owned by a hosting company in Germany called Servinga.

Looking up IP blocks Autonomous Systems are essentially organizations to which IPv4 and IPv6 blocks have been allocated. These allocations can be looked up easily on the command line either using a third-party service: 
$ curl -sL https://ip.guide/as207408   jq .routes.v4 >> servinga
$ curl -sL https://ip.guide/as207408   jq .routes.v6 >> servinga
or a local database downloaded from IPtoASN. This is what I ended up with in the case of Servinga: 
[
  "45.11.183.0/24",
  "80.77.25.0/24",
  "194.76.227.0/24"
]
[
  "2a0b:7140:1::/48"
]

Preventing comment submission While I do want to eliminate this source of spam, I don't want to block these datacentre IP addresses outright since legitimate users could be using these servers as VPN endpoints or crawlers. I therefore added the following to my Apache config to restrict the CGI endpoint (used only for write operations such as commenting): 
<Location /blog.cgi>
        Include /etc/apache2/spammers.include
        Options +ExecCGI
        AddHandler cgi-script .cgi
</Location>
and then put the following in /etc/apache2/spammers.include: 
<RequireAll>
    Require all granted
    # https://ipinfo.io/AS207408
    Require not ip 46.11.183.0/24
    Require not ip 80.77.25.0/24
    Require not ip 194.76.227.0/24
    Require not ip 2a0b:7140:1::/48
</RequireAll>
Finally, I can restart the website and commit my changes: 
$ apache2ctl configtest && systemctl restart apache2.service
$ git commit -a -m "Ban all IP blocks from Servinga"

Future improvements I will likely automate this process in the future, but at the moment my blog can go for a week without a single spam message (down from dozens every day). It's possible that I've already cut off the worst offenders. I have published the list I am currently using.

Petter Reinholdtsen: 121 packages in Debian mapped to hardware for automatic recommendation

For some years now, I have been working on a automatic hardware based package recommendation system for Debian and other Linux distributions. The isenkram system I started on back in 2013 now consist of two subsystems, one locating firmware files using the information provided by apt-file, and one matching hardware to packages using information provided by AppStream. The former is very similar to the mechanism implemented in debian-installer to pick the right firmware packages to install. This post is about the latter system. Thanks to steady progress and good help from both other Debian and upstream developers, I am happy to report that the Isenkram system now are able to recommend 121 packages using information provided via AppStream. The mapping is done using modalias information provided by the kernel, the same information used by udev when creating device files, and the kernel when deciding which kernel modules to load. To get all the modalias identifiers relevant for your machine, you can run the following command on the command line: 
find /sys/devices -name modalias -print0   xargs -0 sort -u
The modalias identifiers can look something like this: 
acpi:PNP0000
cpu:type:x86,ven0000fam0006mod003F:feature:,0000,0001,0002,0003,0004,0005,0006,0007,0008,0009,000B,000C,000D,000E,000F,0010,0011,0013,0015,0016,0017,0018,0019,001A,001B,001C,001D,001F,002B,0034,003A,003B,003D,0068,006B,006C,006D,006F,0070,0072,0074,0075,0076,0078,0079,007C,0080,0081,0082,0083,0084,0085,0086,0087,0088,0089,008B,008C,008D,008E,008F,0091,0092,0093,0094,0095,0096,0097,0098,0099,009A,009B,009C,009D,009E,00C0,00C5,00E1,00E3,00EB,00ED,00F0,00F1,00F3,00F5,00F6,00F9,00FA,00FB,00FD,00FF,0100,0101,0102,0103,0111,0120,0121,0123,0125,0127,0128,0129,012A,012C,012D,0140,0160,0161,0165,016C,017B,01C0,01C1,01C2,01C4,01C5,01C6,01F9,024A,025A,025B,025C,025F,0282
dmi:bvnDellInc.:bvr2.18.1:bd08/14/2023:br2.18:svnDellInc.:pnPowerEdgeR730:pvr:rvnDellInc.:rn0H21J3:rvrA09:cvnDellInc.:ct23:cvr:skuSKU=NotProvided
pci:v00008086d00008D3Bsv00001028sd00000600bc07sc80i00
platform:serial8250
scsi:t-0x05
usb:v413CpA001d0000dc09dsc00dp00ic09isc00ip00in00
The entries above are a selection of the complete set available on a Dell PowerEdge R730 machine I have access to, to give an idea about the various styles of hardware identifiers presented in the modalias format. When looking up relevant packages in a Debian Testing installation on the same R730, I get this list of packages proposed: 
% sudo isenkram-lookup
firmware-bnx2x
firmware-nvidia-graphics
firmware-qlogic
megactl
wsl
%
The list consist of firmware packages requested by kernel modules, as well packages with program to get the status from the RAID controller and to maintain the LAN console. When the edac-utils package providing tools to check the ECC RAM status will enter testing in a few days, it will also show up as a proposal from isenkram. In addition, once the mfiutil package we uploaded in October get past the NEW processing, it will also propose a tool to configure the RAID controller. Another example is the trusty old Lenovo Thinkpad X230, which have hardware handled by several packages in the archive. This is running on Debian Stable: 
% isenkram-lookup 
beignet-opencl-icd
bluez
cheese
ethtool
firmware-iwlwifi
firmware-misc-nonfree
fprintd
fprintd-demo
gkrellm-thinkbat
hdapsd
libpam-fprintd
pidgin-blinklight
thinkfan
tlp
tp-smapi-dkms
tpb
%
Here there proposal consist of software to handle the camera, bluetooth, network card, wifi card, GPU, fan, fingerprint reader and acceleration sensor on the machine. Here is the complete set of packages currently providing hardware mapping via AppStream in Debian Unstable: air-quality-sensor, alsa-firmware-loaders, antpm, array-info, avarice, avrdude, bmusb-v4l2proxy, brltty, calibre, colorhug-client, concordance-common, consolekit, dahdi-firmware-nonfree, dahdi-linux, edac-utils, eegdev-plugins-free, ekeyd, elogind, firmware-amd-graphics, firmware-ath9k-htc, firmware-atheros, firmware-b43-installer, firmware-b43legacy-installer, firmware-bnx2, firmware-bnx2x, firmware-brcm80211, firmware-carl9170, firmware-cavium, firmware-intel-graphics, firmware-intel-misc, firmware-ipw2x00, firmware-ivtv, firmware-iwlwifi, firmware-libertas, firmware-linux-free, firmware-mediatek, firmware-misc-nonfree, firmware-myricom, firmware-netronome, firmware-netxen, firmware-nvidia-graphics, firmware-qcom-soc, firmware-qlogic, firmware-realtek, firmware-ti-connectivity, fpga-icestorm, g810-led, galileo, garmin-forerunner-tools, gkrellm-thinkbat, goldencheetah, gpsman, gpstrans, gqrx-sdr, i8kutils, imsprog, ledger-wallets-udev, libairspy0, libam7xxx0.1, libbladerf2, libgphoto2-6t64, libhamlib-utils, libm2k0.9.0, libmirisdr4, libnxt, libopenxr1-monado, libosmosdr0, librem5-flash-image, librtlsdr0, libticables2-8, libx52pro0, libykpers-1-1, libyubikey-udev, limesuite, linuxcnc-uspace, lomoco, madwimax, media-player-info, megactl, mixxx, mkgmap, msi-keyboard, mu-editor, mustang-plug, nbc, nitrokey-app, nqc, ola, openfpgaloader, openocd, openrazer-driver-dkms, pcmciautils, pcscd, pidgin-blinklight, ponyprog, printer-driver-splix, python-yubico-tools, python3-btchip, qlcplus, rosegarden, scdaemon, sispmctl, solaar, spectools, sunxi-tools, t2n, thinkfan, tlp, tp-smapi-dkms, trezor, tucnak, ubertooth, usbrelay, uuu, viking, w1retap, wsl, xawtv, xinput-calibrator, xserver-xorg-input-wacom and xtrx-dkms. In addition to these, there are several with patches pending in the Debian bug tracking system, and even more where no-one wrote patches yet. Good candiates for the latter are packages with udev rules but no AppStream hardware information. The isenkram system consist of two packages, isenkram-cli with the command line tools, and isenkram with a GUI background process. The latter will listen for dbus events from udev emitted when new hardware become available (like when inserting a USB dongle or discovering a new bluetooth device), look up the modalias entry for this piece of hardware in AppStream (and a hard coded list of mappings from isenkram - currently working hard to move this list to AppStream), and pop up a dialog proposing to install any not already installed packages supporting this hardware. It work very well today when inserting the LEGO Mindstorms RCX, NXT and EV3 controllers. :) If you want to make sure more hardware related packages get recommended, please help out fixing the remaining packages in Debian to provide AppStream metadata with hardware mappings. As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b.

18 January 2025

Petter Reinholdtsen: What is the most supported MIME type in Debian in 2025?

Seven and twelve years ago, I measured what the most supported MIME type in Debian was, first by analysing the desktop files in all packages in the archive, then by analysing the DEP-11 AppStream data set. I guess it is time to repeat the measurement, only for unstable as last time: Debian Unstable: 
  count MIME type
  ----- -----------------------
     63 image/png
     63 image/jpeg
     57 image/tiff
     54 image/gif
     51 image/bmp
     50 audio/mpeg
     48 text/plain
     42 audio/x-mp3
     40 application/ogg
     39 audio/x-wav
     39 audio/x-flac
     36 audio/x-vorbis+ogg
     35 audio/x-mpeg
     34 audio/x-mpegurl
     34 audio/ogg
     33 application/x-ogg
     32 audio/mp4
     31 audio/x-scpls
     31 application/pdf
     29 audio/x-ms-wma
The list was created like this using a sid chroot: 
cat /var/lib/apt/lists/*sid*_dep11_Components-amd64.yml.gz   \
  zcat   awk '/^  - \S+\/\S+$/  print $2  '   sort   \
  uniq -c   sort -nr   head -20
It is nice to see that the same number of packages now support PNG and JPEG. Last time JPEG had more support than PNG. Most of the MIME types are known to me, but the 'audio/x-scpls' one I have no idea what represent, except it being an audio format. To find the packages claiming support for this format, the appstreamcli command from the appstream package can be used: 
% appstreamcli what-provides mediatype audio/x-scpls   grep Package:   sort -u
Package: alsaplayer-common
Package: amarok
Package: audacious
Package: brasero
Package: celluloid
Package: clapper
Package: clementine
Package: cynthiune.app
Package: elisa
Package: gtranscribe
Package: kaffeine
Package: kmplayer
Package: kylin-burner
Package: lollypop
Package: mediaconch-gui
Package: mediainfo-gui
Package: mplayer-gui
Package: mpv
Package: mystiq
Package: parlatype
Package: parole
Package: pragha
Package: qmmp
Package: rhythmbox
Package: sayonara
Package: shotcut
Package: smplayer
Package: soundconverter
Package: strawberry
Package: syncplay
Package: vlc
%
Look like several video and auto tools understand the format. Similarly one can check out the number of packages supporting the STL format commonly used for 3D printing: 
% appstreamcli what-provides mediatype model/stl   grep Package:   sort -u
Package: cura
Package: freecad
Package: open3d-viewer
%
How strange the slic3r and prusa-slicer packages do not support STL. Perhaps just missing package metadata? Luckily the amount of package metadata in Debian is getting better, and hopefully this way of locating relevant packages for any file format will be the preferred one soon. As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address 15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b.

Dominique Dumont: How we solved storage API throttling on our Azure Kubernetes clusters

Hi This issue was quite puzzling, so I m sharing how we investigated this issue. I hope it can be useful for you. My client informed me that he was no longer able to install new instances of his application. k9s showed that only some pods could not be created, only the ones that created physical volume (PV). The description of these pods showed a HTTP error 429 when creating pods: New PVC could not be created because we were throttled by Azure storage API. This issue was confirmed by Azure diagnostic console on Kubernetes ( menu Diagnose and solve problems Cluster and Control Plane Availability and Performance Azure Resource Request Throttling ). We had a lot of throttling:
2025-01-18_11-01-k8s-throttles.png
Which were explained by the high call rate:
2025-01-18_11-01-k8s-calls.png
The first clue was found at the bottom of Azure diagnostic page:
2025-01-18_11-27-throttles-by-user-agent.png
According, to this page, throttling is done by services whose user agent is: 
Go/go1.23.1 (amd64-linux) go-autorest/v14.2.1 Azure-SDK-For-Go/v68.0.0
storage/2021-09-01microsoft.com/aks-operat azsdk-go-armcompute/v1.0.0 (go1.22.3; linux)
The main information is Azure-SDK-For-Go, which means the program making all these calls to storage API is written in Go. All our services are written in Typescript or Rust, so they are not suspect. That leaves controllers running in kube-systems namespace. I could not find anything suspects in the logs of these services. At that point I was convinced that a component in Kubernetes control plane was making all those calls. Unfortunately, AKS is managed by Microsoft and I don t have access to the control plane logs. However, we re realized that we had quite a lot of volumesnapshots that are created in our clusters using k8s-scheduled-volume-snapshotter: We suspected that kubernetes reconciliation loop is throttled when checking the status of all these snapshots. May be so, but we also had the same issues and throttle rates on preprod and prod were the number of snapshots were quite different. We tried to get more information using Azure console on our snapshot account, but it was also broken by the throttling issue. We were so puzzled that we decided to try L odagan s advice (tout cr mer pour repartir sur des bases saines, loosely translated as burn everything down to start from scratch ) and we destroyed piece by piece our dev cluster while checking if the throttling stopped. First, we removed all our applications, no change. Then, all ancillary components like rabbitmq, cert-manager were removed, no change. Then, we tried remove the namespace containing our applications. But, we faced another issue: Kubernetes was unable to remove the namespace because it could not destroy some PVC and volumesnapshots. That was actually good news, because it meant that we were close to the actual issue. We managed to destroy the PVC and volumesnapshots by removing their finalizers. Finalizers are some kind of markers that tell kubernetes that something needs to be done before actually deleting a resource. The finalizers were removed with a command like: 
kubectl patch volumesnapshots $ volumesnapshot  \
  -p ' \"metadata\": \"finalizers\":null '  --type merge
Then, we got the first progress : the throttling and high call rate stopped on our dev cluster. To make sure that the snapshots were the issue, we re-installed the ancillary components and our applications. Everything was copacetic. So, the problem was indeed with PVC and snapshots. Even though we have backups outside of Azure, we weren t really thrilled at trying L odagan s method on our prod cluster So we looked for a better fix to try on our preprod cluster. Poking around in PVC and volumesnapshots, I finally found this error message in the description on a volumesnapshotcontents: 
Code="ShareSnapshotCountExceeded" Message="The total number of snapshots
for the share is over the limit."
The number of snapshots found in our cluster was not that high. So I wanted to check the snapshots present in our storage account using Azure console, which was still broken. Fortunately, Azure CLI is able to retry HTTP calls when getting 429 errors. I managed to get a list of snapshots with 
az storage share list --account-name [redacted] --include-snapshots \
      tee preprod-list.json
There, I found a lot of snapshots dating back from 2024. These were no longer managed by Kubernetes and should have been cleaned up. That was our smoking gun. I guess that we had a chain of events like: To make things worse, k8s-scheduled-volume-snapshotter creates new snapshots when it cannot list the old ones. So we had 4 new snapshots per day instead of one. Since we had the chain of events, fixing the issue was not too difficult (but quite long ):
  1. stop k8s-scheduled-volume-snapshotter by disabling its cron job
  2. delete all volumesnapshots and volume snapshots contents from k8s.
  3. since Azure API was throttled, we also had to remove their finalizers
  4. delete all snapshots from azure using az command and a Perl script (this step took several hours)
  5. re-enable k8s-scheduled-volume-snapshotter
After these steps, preprod was back to normal. I m now applying the same recipe on prod. We still don t know why we had all these stale snapshots. It may have been a human error or a bug in k8s-scheduled-volume-snapshotter. Anyway, to avoid this problem is the future, we will: My name is Dominique Dumont, I m a devops freelance. You can find the devops and audit services I propose on my website or reach out to me on LinkedIn. All the best

17 January 2025

C.J. Collier: Security concerns regarding OpenSSH mac sha1 in Debian

What is HMAC? HMAC stands for Hash-Based Message Authentication Code. It s a specific way to use a cryptographic hash function (like SHA-1, SHA-256, etc.) along with a secret key to produce a unique fingerprint of some data. This fingerprint allows someone else with the same key to verify that the data hasn t been tampered with. How HMAC Works Keyed Hashing: The core idea is to incorporate the secret key into the hashing process. This is done in a specific way to prevent clever attacks that might try to bypass the security.
Inner and Outer Hashing: HMAC uses two rounds of hashing. First, the message and a modified version of the key are hashed together. Then, the result of that hash, along with another modified version of the key, are hashed again. This two-step process adds an extra layer of protection. HMAC in OpenSSH OpenSSH uses HMAC to ensure the integrity of messages sent back and forth during an SSH session. This prevents an attacker from subtly modifying data in transit. HMAC-SHA1 with OpenSSH: Is it Weak? SHA-1 itself is considered cryptographically broken. This means that with enough computing power, it s possible to find collisions (two different messages that produce the same hash). However, HMAC-SHA1 is generally still considered secure for most purposes. This is because exploiting weaknesses in SHA-1 to break HMAC-SHA1 is much more difficult than just finding collisions in SHA-1. Should you use it? While HMAC-SHA1 might still be okay for now, it s best practice to move to stronger alternatives like HMAC-SHA256 or HMAC-SHA512. OpenSSH supports these, and they provide a greater margin of safety against future attacks. In Summary HMAC is a powerful tool for ensuring data integrity. Even though SHA-1 has weaknesses, HMAC-SHA1 in OpenSSH is likely still safe for most users. However, to be on the safe side and prepare for the future, switching to HMAC-SHA256 or HMAC-SHA512 is recommended. Following are instructions for creating dataproc clusters with sha1 mac support removed: I can appreciate an excess of caution, and I can offer you some code to produce Dataproc instances which do not allow HMAC authentication using sha1. Place code similar to this in a startup script or an initialization action that you reference when creating a cluster with gcloud dataproc clusters create: 
#!/bin/bash
# remove mac specification from sshd configuration
sed -i -e 's/^macs.*$//' /etc/ssh/sshd_config
# place a new mac specification at the end of the service configuration
ssh -Q mac   perl -e \
  '@mac=grep  chomp; ! /sha1/  ; print("macs ", join(",",@mac), $/)' >> /etc/ssh/sshd_config
# reload the new ssh service configuration
systemctl reload ssh.service
If this code is hosted on GCS, you can refer to it with 
--initialization-actions=CLOUD_STORAGE_URI,[...]
or 
--metadata startup-script-url=CLOUD_STORAGE_URI,[...]

Next.