Search Results: "bap"

10 September 2026

Matthias Klumpp: JPEG-XL as default in AppStream, and better media processing

Two weeks ago, I released AppStream 1.2.0. This release contains a lot of great changes, but one of the most important ones concerns how media are being handled, and AppStream s default image export format.

AppStream is a Freedesktop metadata standard to describe software components. That can be anything from system services over fonts to console and graphical applications. AppStream metadata is supposed to give users enough information to decide whether they want to install a piece of software, to represent that piece of software, and to give the operating system enough information to decide whether a software component should be installed automatically and (to some extent) what capabilities and relations it has, to provide the user with sensible options.

Especially for the first two goals, and especially for GUI applications, AppStream supports icons and screenshots, which are used to showcase applications. Today, AppStream is used by all kinds of services, from Linux distributions over firmware updates to Flatpak and desktops directly. AppStream s original design however comes from the perspective of Linux distributions in 2011, where you may want to browse the software catalog offline, without delay, and without pinging an external server (which could be a privacy concern).

Therefore, a common way to deploy an AppStream-enabled software repository is to ship all icons of all applications in the repository to the user as part of the repository metadata download. AppStream does support remote icon downloads nowadays, and for a while I thought that this would become the default eventually. However, especially in today s world, having a bandwidth-saving, instantly responsive, privacy-protecting application browsing experience seems more important that ever.

PNG images are great!

The only format that AppStream supports for icons and screenshots (which are downloaded on-demand from your distributor s CDN) has always been exclusively PNG. PNG images are perfect for icons, because they compress well (especially for common icon shapes), are fast and simple to load, and can be loaded anywhere, by any toolkit or webbrowser. They also ensure we deliver faithful screenshot images, even though we may have scaled or re-rendered them. Still though, PNG images are less great for screenshots, as they are not very efficient, which puts strain on any CDN that has to deliver them, as well as on people s internet connections when browsing screenshots. Having smaller thumbnails alleviates that problem a little, but does not fully solve it.

But even for icons, PNG could be improved upon: In many cases, icons are re-downloaded with the repository metadata again and again, so having a large icon tarball adds up to the data transferred during metadata refreshes. AppStream also now supports large 128x128px icons, which nobody in 2012 expected we would need, adding even more data that will be re-downloaded. Saving some space here translates directly to lower bandwidth costs as well as faster downloads for users.

To improve PNG file sizes, the AppStream Compose library, which handles all image processing and metadata catalog composition, was running optipng on all generated PNG images. That does create smaller PNG images, but they were still relatively large compared to other image formats.

For a long time though, there was no alternative to PNG images for icons: There was no lossless image compression format that could give us the same quality as PNG images and that was also widely supported.

JPEG-XL vs PNG in AppStream

Since 2021 we have JPEG-XL (JXL), which offers a true lossless mode with often better compression than PNG. The issue was that JPEG-XL wasn t widely supported. Then, in 2025, the PDF Association selected JPEG-XL as the preferred image format for HDR images in PDFs, and now we are finally getting browser support and more ubiquitous availability of the format (you can try it right now in Firefox!).

For screenshots, using JXL s lossy mode, it has obvious and extreme size advantages over PNG, so supporting JXL or WebP for screenshot images was an obvious choice. If JXL would support the lossless case very well as well though, we could serve many use cases with the same exported image format, which is very attractive to me.

So, the obvious next question was whether it was worth the pain of switching the icon format, so I did some measurements on real icons. For that I used the AppStream component icon pool that Debian Unstable ships, which is almost 5000 application icons of various sizes, and converted them to PNG:

Icon sizeIconsPNG totalJXL totalPool savedPNG avgJXL avgMedian savedMean saved Worst BestLarger as JXL
48 48 1544 3.7 MiB 3.0 MiB 17.8%2.4 KiB2.0 KiB 17.9% 16.7%-118.7%60.0% 206
64 64 2018 7.0 MiB 5.8 MiB 17.8%3.6 KiB2.9 KiB 18.0% 15.8%-112.7%70.0% 279
128 128 1411 11.2 MiB 8.7 MiB 22.0%8.1 KiB6.3 KiB 20.1% 17.5% -89.7%61.0% 209
TOTAL 4973 21.9 MiB 17.5 MiB 19.9%4.5 KiB3.6 KiB 18.6% 16.6%-118.7%70.0% 694
PNG images saved with libpng at effort=4, compression=9, then optimized using optipng -o2, JXL images encoded using vips jxlsave lossless=1 effort=7 strip=1 via VIPS/libjxl.

As the table shows, using lossless JXL images over size-optimized PNG images (using optipng s default settings) provides a roughly 20% gain. This does not look like much, until you consider how often these files are downloaded: A 20% file size reduction may only save 1-2 MiB of disk space, but if they are downloaded over and over again by many clients, it will save a lot of bandwidth.

Interesting JXL encoding findings

As a sidequest, I was curious why some images were larger than their PNG counterparts when encoded with JXL, and what the ones that were significantly smaller were.

In short, the biggest size reductions for JXL existed on images that were already small as PNG, and contained large, flat color surfaces with hard edges and simple shapes. They were not very interesting, and much of JXL s wins come from accumulating smaller gains across all files, which compound the bigger icons get (especially at 128x128px, where JXL truly shines).

The events were JXL loses to PNG are more interesting: For example, it does quite poorly with pixel-art images that have a lot of repeating patterns. Those are encoded well by PNG, but less efficiently by JXL. Take for example Vonsh:

Icon of Vonsh, an SDL-based snake game, which PNG compresses better than JXL

My guess is that while PNG can exploit the repeating pixel patterns for compression, JXL s predicts surrounding pixels from its neighbours, which fails too often and makes it pay almost full entropy per pixel. In this single rare case, the PNG is at 5.4 KiB, while the JXL is almost 8 KiB in size.

Other cases I looked at were arguably buggy input data, where color channels were hidden under the alpha channel of the input image. PNG could probably again exploit repeats, while we were forcing JXL to encode pixels that were invisible in the final image. This is arguably a problem with the original input data. Currently, AppStream does not make any changes to icons at all, but in future we might add a filter that removes invisible colors from images to solve this pathological case (it was only two icons out of 5000 though, so it is not a high priority).

The third case I found where JXL loses to PNG were icons with checkerboard-like patterns:

Icon of x3270, an IBM 3270 Terminal Emulator

For those, PNG can likely again exploit the repeating patterns, while a checkerboard layout is pretty bad for left/top predictors like JXL s. However, in this case the size difference (and loss for JXL) is only 450 bytes, so even though JXL loses to PNG, it does so not by much.

JXL in AppStream

Given these findings, JPEG-XL is the default image format starting with AppStream 1.2.0. AppStream Compose will encode all images losslessly as JXL, while screenshots are encoded in lossy mode at Q=90 effort=7. Since the optipng step does not happen for JXL images, this comes at no speed penalty and is even a bit faster on modern x86_64 CPUs (where libjxl can use SIMD). PNG is still available, and Compose can be told to switch between the two formats.

Upsides of JXL in AppStream right now

If you use JXL in Compose or the recent release of appstream-generator, you will get much smaller images and, for screenshots, will benefit from other JPEG-XL features such as progressive decoding, providing a far nicer user experience. libAppStream has supported JXL icons since version 1.1.3, so your clients will need that version or a newer one, and all software centers will have to support loading JXL images (which all of them do, provided the right plugins are installed).

Downsides of switching to JXL too quickly

JXL is a very new format, so web browsers might not yet display it if you are serving webpages. Your clients may also have bugs in processing JXL images, as the format is still new . For example, switching on JXL in Debian sent KDE Discover into an infinite loop on startup while trying to load the icons (an issue which has been fixed, but clients will need that patch first before JXL is switched on).

This currently makes JXL enablement only possible when you know that your clients can support it. This is the case for me in Debian Unstable and Debian 14, which are using JXL images for a few weeks now, but not for any older releases. Platforms like Flatpak have it even harder, because they do know even less about their clients. So, even though it has big advantages, you may want to hold off on using JXL right away, and force PNG by setting the ImageFormat key to png in appstream-generator s configuration, or passing --image-format=png to appstreamcli compose.

It is also worth mentioning that JPEG-XL is much, much slower on systems that do not have SIMD instructions or for which the libjxl/jxl-rs library does not have them (such as apparently riscv64 right now). If this is a concern, you might not want to switch to JXL right away.

Media pipeline improvements

Besides the JXL default change, AppStream 1.2.0 also comes with a complete overhaul of its media processing pipeline. While libappstream, AppStream s main library, does not do any media processing and comes with very minimal dependencies to be embedded in client applications and used on servers, the same can not be said about libappstream-compose, AppStream s library to build metadata generating applications (the server-side part, usually).

The compose library has to render fonts into font specimen cards, inspect translation files, render SVG images, decode all kinds of raster images, inspect video files, etc. Especially the fonts, and the fact that fonts can appear in SVG images, has caused issues in the past, as libappstream-compose is a heavily threaded library and most font libraries can only work from a single thread. This forced the library to essentially go into single-thread mode anytime anything that could touch a font was being processed.

AppStream also originally was created for a safe world where applications were vetted by the distributors before their metadata was processed. This is increasingly not the case, so it made sense to put at least a few guardrails on the most complex part of the pipeline: The media processing. As part of the change, media processing was split out into a separate worker process. This solved two problems at once: Font handling was isolated in a single-threaded binary if we wanted to handle fonts in parallel, we could simply spawn more workers. And, being in a separate process, the media processing could now be sandboxed.

As part of the multiprocess changes, Compose also switched from using GdkPixbuf to VIPS for image processing. The latter allows for much more fine-grained control over the image output and encoding, and comes with a lot of well-maintained filters and operations, which made it possible to eliminate a fair chunk of AppStream s hand-rolled image processing operations. As part of this transition, we unfortunately lost the ability to read XPM images, which dropped about 20-30 applications from the pool at Debian. But in the name of security, this is a sensible choice, especially since most XPM icons were very small and low-resolution, and applications using them could benefit from adding a high-quality PNG icon anyway. With VIPS, we also now restrict the amount of image formats we can load to a sensible set, so extremely niche or unexpected formats will be outright rejected (this includes sane-but-unusual formats for screenshots and icons, such as TIFF images).

The Compose library, with all of these changes, will now just request high-level operations (e.g. render a font card for this font to a JXL image ) from the worker, and provide it with input data in sealed memfds and output locations as FDs as well. On Linux systems, the worker will use Landlock if available, to block all write access to the filesystem, deny device access and deny TCP and UDP as well. The sandbox can certainly be tightened a fair bit in future, but this was a good and safe start to gain some experience with it without having things break too easily, given the many places Compose is used in (also, Landlock s API is surprisingly nice to use, so it was easier than I thought to add in this early version).

With all of these changes, the libappstream-compose library is now also officially marked API-stable, so you should be able to rely on it in future to build new things (its API has barely changed in the past, and now with the new media API and defaults change in place, it was time to declare it stable).

I want to see / try this!

Currently, the easiest way to have a look at the new data is to check out Debian Unstable. If you have a JXL-enabled browser, you can also see the icons in AppStream Generator s HTML pages for Debian Sid. If you are using appstream-generator for your distribution, you will also get much more pleasant statistics and HTML pages, as well as fully deterministic media output and a whole bunch of security updates, so, update to its recent 1.0 release.

Please keep in mind that if you switch to JXL, the client tools receiving the image data have to support it. Support varies depending on the Linux distribution, so, test it first and switch the default back to PNG in case you encounter any issues.

What s next?

With so many features and changes landed, the next changes in AppStream will focus on improving what already exists and fixing any issues (there will be more blogposts about the other features 1.2.x delivers!). Testing with the entire Debian archive as data source makes me fairly confident though that there will not be many problems. In the longer term, tightening the media processing sandbox will also be something we might want to do, e.g. by hiding parts of the filesystem tree or filtering syscalls.

For JPEG-XL, one obvious question is Will you add support for it to the Freedesktop icon-theme specification as supported format alongside PNG, SVG(Z), and XPM? . For on-disk icon repositories, JXL s space-savings are less compelling, and it being HDR-capable is also not necessarily a killer feature (PNG can go a long way!). However, JPEG-XL s ability to immediately decode larger images at reduced resolution without resampling could legitimately be very powerful here, as applications could ship a single large image and quickly decode it at 1/2, 1/4 or 1/8 the size for different purposes in their UI. JPEG-XL also supports spot-color extra channels, which applications could use as masks to recolor raster icons at render time. This could be incredibly nice to color symbolic icons on-the-fly without any SVG and CSS. JXL also provides richer metadata, which might be neat for (license/author) documentation. So, the answer here is: Maybe it makes sense to allow another format, but this will have to be discussed first, as it would force JXL into every toolkit and desktop, which is a much bigger ask than supporting it only in AppStream.

As always, let me know what you think and please report any issues or bugs directly against AppStream or AppStream Generator if you encounter problems that are with the tools, and not with a project s metadata.

24 August 2026

Matthias Klumpp: Sovereign Tech Fellowship for Freedesktop Tasks

In 2025 I was honored to be selected for the first cohort of Sovereign Tech Fellows, a program by Germany s Sovereign Tech Agency to improve the resilience of the open source ecosystem by supporting maintainers directly (complementing their existing support for larger FOSS organizations). Back in 2025, I was only working very limited hours however, this has changed in 2026.

For the second half of 2026, I am working again as a Sovereign Tech Fellow, but this time with significantly increased hours. After finishing my PhD, I do have time now for new tasks (and new jobs!), and the fellowship presents an amazing opportunity to really advance projects that I maintain or am part of. This also has a very nice effect on contributors and bug reporters, as their feedback gets addressed a lot faster. With some luck, this ultimately will help finding new (co)maintainers for projects as well (although in the age of AI, a lot of how open source used to work is much more uncertain, but that is a matter for a different blog post).

The fellowship is time-limited, so I am intending to make the time I currently have count!

So, what s planned?

I am involved in many projects, but three of them will be getting attention as part of the fellowship. I know I am notoriously slow at blogging, but expect more details on each of them very soon. Here s an overview:

Freedesktop.org, Specifications and Organization

I maintain the Freedesktop Specifications, which is an area of Freedesktop that has traditionally been a bit chaotic. This worked in the past, because Freedesktop was never intended to be a formal standards body, but more a shared space where people could throw a lot of code and ideas over the wall and see what sticks and what people can collaborate on.

While I very much love the spirit of this and want to keep it in some form, we definitely would benefit not just from more formalization and better procedures, but also from better organization of the specifications in general. A lot of conflicts can be avoided by that. I will work on improving procedures, crunching through the (lots!) of pending bug reports and MRs, and to make the specifications site better searchable and accessible (similar to how Mozilla s MDN presents information, but I am not sure if we will get quite that far). I also intent to add a compatibility matrix for specifications, so if a desktop opts out of any one of them (or does not implement them yet) that fact is documented and authors of applications know what they can expect. This will allow us to move a lot faster and avoid a lot of conflict, because there is no implicit assumption that everybody will implement everything anymore (which has never been quite true anyway).

Hopefully, this will ultimately result in a Freedesktop that is both a lot more useful for application authors who want to bring their project to Linux, as well as developers of desktop environments who need to see which specifications are available and which ones are current.

In addition to that, I have also worked on a Freedesktop.org website refresh, which is pretty much done in its first iteration (pending sysadmin action). The aim there is to have a more official website, separate from user-contributed wiki content, that showcases what Freedesktop is and which projects are using it for hosting. Once the new website is live, I will also review every page again, archive dead projects in their own section and reorganize the software and specifications directory. Those sections are severely outdated and are missing recent efforts from the community, while still containing long-dead old projects (remember HAL? ).

AppStream

A lot of extra maintenance work will be (has been!) done on it. This includes things such as JPEG-XL support (blog post soon), sandboxed media processing, support for newer specification additions, better OARS integration (and potentially migrating it to fd.o infrastructure), improvements and API stabilization for libappstream-compose and a lot of bugfixing and resolution of issues found by AI code review.

AppStream was originally designed to parse only trusted data from vetted Linux distribution sources this is no longer the case in today s world and in the way Flatpak uses it, so we need to increase resilience of the project.

I am also exploring a project that could vastly improve search accuracy for AppStream. Stay tuned for that.

PackageKit & System Upgrades

Many years ago, people thought we would all migrate to atomic Linux distributions and slowly not need PackageKit anymore. This has not turned out to be the case, and there are still plenty of reasons to use a package-based OS, especially in development environments. At the same time, PackageKit has been basically the same for years, and its older architecture is beginning to show. It being a daemon who s literal job it is to modify the entire system also makes it one of the most security-sensitive components that a Linux system can have, while simultaneously making it near-impossible to sandbox.

My plan is to create PackageKit 2.0 by building on the great foundation of PackageKit 1.0, but modernizing it. This will include simplifying its code and removing a bunch of features that have no more use in modern desktops, while also adding some features that PackageKit never had but that would be useful to expose to frontends (still no to interactivity an terminal-progress forwarding though!). PK 2.0 will also allow me to solve a few design issues that have been worked around in the past, by replacing them with better solutions. This will be a painful transition, as PackageKit 2.0 will break all interfaces PackageKit has and those interfaces have been frozen for more than a decade. However, I do fully expect this change to be worth the effort.

In addition to that, I intend to look into the offline-update procedure again and improve it. The current multi-reboot operation comes with downsides, that newer systemd features such as soft-reboot can alleviate. The end result should be a much smoother, less annoying offline-update experience for users (I especially want to get rid of updates running on system startup, which I consider quite bad from a usability perspective). The new behavior is in the early drafting stages and may need direct support from systemd. I will share more about it once I can.

That s a lot of tasks!

Yes! I will see how far I get. I am moving project-by-project though, to allow me to focus on one project at a time, rather than scattering my attention continuously. Amazingly, this means that the major tasks for AppStream are already almost done, and we are nearing the 1.2.0 release. AppStream got priority, because the new Freedesktop Flatpak runtime will be released soon, and because I want FlatHub/Flatpak to have access to the new AppStream release sooner. Freedesktop and PackageKit are next on the task list.

Either way, a lot of progress is coming if you have any feedback or want to help out, please don t hesitate to reach out! All work is happening fully in the open, so you can also chime in on the respective GitHub/GitLab tasks .

You can also expect blog posts about key features or interesting changes, so stay tuned!

2 July 2026

Matthew Garrett: Preventing token theft

When you log into a service you re given an authentication token. Each further request to the site includes that token, allowing the server to figure out who you are and ensuring that you have access to your data. Depending on site policy, this token may either be stored in memory (and so vanish if you restart your browser) or disk. The token is the proof of your identity. As far as the site is concerned, anyone with your token is you. These tokens may be traditional browser cookies, but they may also be stored in either site local storage or (if you re not using a browser) in some other storage location. In recent years we ve seen infostealer malware (like LummaC2) gain the ability to exfiltrate user tokens, allowing attackers to gain access to the user s data without needing to retain access to the user s machine. This attack is viable even if the site has strong MFA requirements, so passkeys don t help. Encrypting the tokens on disk doesn t prevent the malware from scraping them out of the browser s RAM or obtaining whatever key is used to encrypt them. This feels like a pretty hard problem to solve. But that hasn t stopped people from trying! Dirk Balfanz wrote an IETF draft describing a mechanism for using self-signed certificates for TLS authentication. This uses the mutual authentication feature of the TLS protocol that requires both sides prove their identity to each other. In regular TLS, the remote site presents a signed certificate that tells you who it is. When performing mutual authentication, you then present a certificate to the remote site telling it who you are. These client certificates are largely unused outside enterprise environments because they re a huge pain to deploy. It s not so much that this has sharp edges, it s that it s entirely made of sharp edges. Managing certificate deployment to your devices is hard. Browsers get confused if the certificates change under them. You have one certificate and it lives forever, so sites you present it to can track your identity. Users are prompted to choose a certificate to authenticate with, and if they pick the wrong one everything breaks and is hard to recover. I ve deployed this and I did not have a good time. But Balfanz s idea was simple. Rather than require certificates to be deployed, browsers would simply generate a certificate on the fly. The goal wasn t to prove the device or user s identity in any global way - but it would associate a TLS session with a specific certificate. You could then, for example, include a hash of the certificate in the cookie, and if someone tried to use that cookie without presenting that certificate then the cookie could be rejected. If the browser used a hardware-backed private key for the certificate then it would be impossible for an attacker to steal it. Sure, you could still steal cookies, but you wouldn t be able to use them. This was written almost 15 years ago, and seems simple, elegant, and functional. It didn t happen. Part of the reason for that is that, well, it wasn t quite so simple. One problem was privacy related. Cookies are only sent after the TLS session is established, so anyone monitoring the network doesn t know anything about the user identity. A naive implementation of this approach would have meant the client certificate being sent before session establishment, and now user identity can be tracked (no longer an issue if this was implemented on top of TLS 1.3, but this was a log time ago). This was avoided by reordering the client handshake, but that meant having to modify the TLS specification and implementations would have to be updated to support this. Another was that figuring out the granularity of the certificates was difficult. You d want to use different certificates for every site to avoid them effectively becoming tracking cookies, but you need to provide the certificate before cookies are set, and you don t know what origin the site is going to set in its cookies. If you generate a certificate for a.example.com and a different one for b.example.com, and a.example.com sets a cookie for *.example.com and includes the certificate you used for a.example.com, that cookie isn t going to work on b.example.com and things are broken. This meant supporting it wasn t as straightforward as it seemed - you d need to ensure that your cookie scope was compatible with the certificate scope. You could probably make this work well enough by aligning it with the Public Suffix List, but there was still some risk of expectations not being aligned. And, perhaps most importantly, TLS session resumption (replaced by pre-shared keys in TLS 1.3) somewhat defeats the purpose of the exercise - clients store state that allows them to re-establish a TLS connection without performing certificate exchange (this reduces overhead if a connection gets interrupted or you switch to a new network or anything along those lines), and anyone in a position to steal cookies could steal that state as well. The followup attempt was channel IDs. This simplified the implementation somewhat - rather than certificates, a raw public key would be sent, along with proof of possession of the private key in the form of a signature over a portion of the TLS handshake. This was required even in the event of session resumption, which avoided having to worry about theft of session secrets. The timing of the exchange was after the encrypted session had been established, so user identity couldn t be leaked that way either. Cookies could then be bound to this identifier. Unfortunately it didn t really deal with the problem of scoping keys in a way that would match cookie requirements, and the spec suggests that the right way of handling this is to scope keys to TLDs, which would enable user tracking across sites (Chrome s implementation apparently restricted it to eTLD+1, which would match the third party cookie policy and avoid the tracking risk). Chrome added support for this, but it was removed in early 2018. The discussion of some of the pain points in that message is interesting, explicitly calling out problems with connection coalescing across domains and the incompatibility with zero-RTT TLS1.3. The overall consensus at the time seems to be that trying to solve this entirely at the TLS layer has too many rough edges, and a different approach should be taken. And so almost 7 years after the initial draft for origin bound certificates, we come to token binding. This ended up being a rather more complex endeavour, covering 3 different RFCs describing how it impacts TLS, how to incorporate it into HTTP, and how to manage all the various parties involved in the process. The short version is that it s pretty similar to channel ID, except that there s also a documented mechanism for allowing tokens to be bound to one party and consumed by another, avoiding any need for widely scoped keys. Token binding effectively solved all the issues in the original proposal, but at the cost of somewhat more complexity. The RFC was finalised in October 2018. Chrome removed its (incomplete, draft) support for token binding in November 2018. Edge carried support until late 2024. Despite getting all the way through the RFC process, it s functionally dead. The process up until this point had been largely initiated by Google, with Microsoft contributing significantly to the token binding standards. The work had been focused on identifying a generic solution to the problem rather than tying it to any specific authentication flow. The next step was in a different direction - rather than trying to fix this for the entire internet, how about we try to fix it for OAuth? RFC 8705 is titled OAuth 2.0 Mutual-TLS Client Authentication and Certificate-Bound Access Tokens . This is basically the 2011 approach, but (a) with an explicit definition of how the certificate should be incorporated into issued auth cookies, and (b) with a proviso that well uh if you re going to use tokens issued by your IdP to authenticate to someone else then well you re going to need to use the same cert for both. This is probably fine for the company-owned-laptop case where you re actually fine with multiple sites being able to tie identities together (that s kind of the point here!), and also works for I am using an app and not a browser , but doesn t work for more generic scenarios. It also doesn t seem to take the session resumption case into account at all? Support for RFC8705 seems poor, as far as I can tell of the big players only Auth0 implements it. In theory it works fine with self-signed client certs but in reality that s going to be almost as difficult to support across multiple platforms as just issuing proper client certs in the first place, so deployment is going to be kind of a pain. But the good news is it doesn t rely on any TLS extensions or custom browser behaviour, so at the client side it works fine with any browser. Which brings us on to RFC 9449, Demonstrating Proof of Possession . This goes even further than RFC8705 in terms of reducing the burden of deployment - it works fine with existing browsers, and it doesn t even require any certs. The client generates a keypair and provides the pubkey when requesting the cookie. The cookie contains the pubkey. Every request to the service now provides the cookie with the pubkey and also provides a signature over the URI and HTTP method. If the signature matches the pubkey in the token then clearly the signature came from the machine the token was issued to, and everything is good. This does come with some downsides, though. The first is that it uses browser interfaces to generate the keys (typically crypto.subtle.generatekey()) and as far as I can tell there are no browsers that guarantee that that key is going to be generated in hardware even if it s marked non-exportable, so anyone able to steal the cookies can also steal the keys. The second is that the signature only covers the URI and HTTP method, and not the message content or any other headers, so anyone able to exfiltrate a valid signature can replay it against the same URI with different message content. The recommended way to handle this is to reject any signatures that weren t generated within the last few seconds, which is a wonderful additional way to allow clock skew to give you a Bad Day. And the third is that every single request has to be separately signed, which is not intrinsically a problem because computers are fast and have multiple cores, but if you re trying to solve the first problem by sticking the key in a TPM then you re dealing with something that s slow and single threaded and that s maybe acceptable if you re using client certificates (because there s going to be one signature per session and you can use the same session for multiple requests) but probably not if you re dealing with a user opening a browser that restores previous tabs and each of those is a webapp that fires off 100 requests in parallel. In case it wasn t clear, I don t like DPoP. It doesn t feel like it actually solves the underlying problem that we see in the real world (malware running in a context where if it can grab the tokens it can grab the keys), it adds a massive amount of overhead, and it has baked in replay vulnerabilities. I don t know why it exists and I m incredibly suspicious of vendors telling me that it fixes my problems, because if they re telling me that then I m going to end up assuming that they either don t understand my problems or they don t understand their technology, and neither of those is good. Still. Then we get to the thing that prompted me to write this - Chrome s announcement that they had launched device-bound session credentials. This is interesting because it s a Chrome feature that s explicitly intended to counter on-device malware, which was one of the things that was out of scope in 2018 when token binding was being removed. Since this is entire web level it doesn t have to be an RFC, and so is instead defined by W3C. I m going to handwave all the complexity and say that it s basically a way to register a public key when a cookie is issued, and then prove possession of the private key when it s time to renew the cookie. By making the cookies shortlived and having support for rotating them in the background, user impact is basically zero and while it s still possible for an attacker to exfiltrate and use a cookie they ll only be able to do so for a short window before it needs to be refreshed - something the attacker can t do, since they don t have the private key. This avoids the DPoP overhead because you only need to do signing once per cookie per cookie lifetime, and not on every single request. I don t like this due to the window where exfiltrated tokens can be used, but it feels like a strict improvement over the status quo. An extension called device-bound session credentials for enterprise allows pre-enrollment of device keys, so even though the actual runtime DBCE flow doesn t involve certificates, certificates can be used for device registration in enterprise environments and you can make sure that auth cookies only go to trusted devices. Unfortunately this is Chrome-only, and so we re going to need to wait for it to be backported to all the random app frameworks for it to have widespread support on mobile or for almost everyone s desktop app that s actually three websites in an Electron wrapper. Mozilla s current position is that they re not in favour of it, so I guess we ll see where Safari lands in terms of broad uptake. The last thing on my list is another client cert/OAuth binding, this one still in draft state at the time of writing. This one is aimed primarily at the use of agent-driven tooling, where you have something running in the background using a whole bunch of tools that are each acting on your behalf. Authenticating to all of them separately isn t a fun time, but giving broadly scoped access tokens to a non-deterministic agent and trusting that it ll never post them somewhere public also isn t a fun time. The key distinction between it and RFC8705 is that it s aimed at connections rather than sessions, which avoids the worries about session resumption. This is done with TLS Exporters, which in TLS 1.3 should be unique to the connection even over session resumption (TLS 1.2 may reuse some of the same key material for exporters over session resumption, so it s recommended to enforce 1.3 for this). By providing a new signature alongside the cookie on every new connection, the client proves that it still has access to the private key. This is a very new spec and I haven t had much time to work through it yet, but my naive understanding is that unlike RFC8705 this would require some additional client support to be able to regenerate the client signature on every TLS reconnection. This doesn t avoid all the problems that RFC8705 has, including how to scope certificates. For the agentic use case that probably doesn t matter - all these tools are acting on behalf of the same user, it s fine if all the sites involved know they re the same user. But it doesn t solve the general purpose user use case, and right now DBSC seems like the best we have there. But. Part of me still wonders whether Dirk Balfanz s approach was the right one. Yes, there s risk associated with TLS session resumption, but in the worst case you could just switch that off for high risk setups. The cookie scope argument is real, and also in cases where it could violate privacy the site owner could already choose to broaden their cookie scope and violate your privacy, and in cases where it breaks things you could just not make use of it. The other problems are largely fixed by TLS 1.3, and then we re just left with Browsers handle client certificates badly to which my answer is Yes, and we should fix that anyway . Despite having a pretty good answer to this solution over a decade ago, the closest we have to actual deployment is something that offers strictly worse security guarantees. And tokens keep getting stolen, and compromises keep occurring, and for the most part people shrug and get on with things.

14 June 2026

Matthias Klumpp: Introducing pkgcli: A nicer command-line interface for PackageKit

For almost two decades, the PackageKit package management abstraction layer has shipped with pkcon as its command-line client. pkcon does its job, but it was always kind of a testing front-end for the PackageKit daemon rather than a tool designed for everyday use. The focus has instead been on the GUI tools, automatic system updates, GUI application managers and other front-ends. Its command names mirror the D-Bus API almost one-to-one (get-details, get-updates, get-depends), output is very plain, and there is no machine-readable mode for scripting. Most importantly though, there has been no development on it at all for almost a decade, so pkcon was stuck in its rudimentary state from that era.

Since a lot of changes will be coming to PackageKit, and testing the daemon and working with it from the command-line was not very pleasant anymore in 2025/2026, I decided to modernize the tool as part of my work as fellow for the Sovereign Tech Agency last year. pkgcli is the new command-line client for PackageKit. It is built from the ground up to be pleasant to use interactively and easy to drive from scripts.

Why a new tool?

Of course, instead of introducing a new tool, I could have just expanded pkcon instead. The problem with that approach is that the pkcon utility has been around for so long and its command-line API had ossified so much, that rather than changing it and potentially breaking a lot of scripts relying on its quirks, I decided to introduce a new tool instead. pkcon can still be optionally compiled for people who need it in their scripts and workflows.

The goals for pkgcli, and the features it now has are:

  • Human-friendly command names. Verbs that read the way you d describe the task, instead of mirroring the D-Bus API 1:1: show, search, list-updates, what-provides, instead of get-details and friends.
  • Readable, colored output by default (still respecting NO_COLOR and degrading gracefully).
  • A real scripting mode. A global --json flag emits JSONL instead of fully human-readable output when possible, to make it easier to use the tool for scripting purposes.
  • Sensible defaults. A few defaults have been changed, such as the metadata cache-age, or automatic cleanup of unused dependencies being enabled by default. This is more in line with current defaults by other tools and frontends. We also print package information in a slightly different, more readable way.
  • Better handling of internationalized text. Text should now align properly in the terminal window, and we should no longer have completely chaotic text output on non-English locales (especially Chinese/Japanese).

Why not pkgctl?

Originally, this tool was called pkgctl, to match other common cross-distro tool names. However, that name was already taken by an Arch-specific distro development tool. When this issue was raised, we decided to just rename our tool to pkgcli with the next release, to avoid the name clash on Arch Linux.

Examples!

Here are some examples on how to use the new tool (some of which include the abridged output pkgcli prints).

Search for anything containing the string editor in name or description, then look at the details of one result: 

$ pkgcli search editor
Querying                  [ ] 100%
  ace-of-penguins 1.5~rc2-7.amd64 [debian-testing-main]
  acorn-fdisk 3.0.6-14.amd64 [debian-testing-main]
  ardour 1:9.2.0+ds-1.amd64 [debian-testing-main]
  audacity 3.7.7+dfsg-1.amd64 [manual:debian-testing-main]
  audacity-data 3.7.7+dfsg-1.all [auto:debian-testing-main]
  augeas-tools 1.14.1-1.1.amd64 [debian-testing-main]
  emacs 1:30.2+1-3.all [debian-testing-main]
  gedit 48.1-9+b1.amd64 [debian-testing-main]
  gedit-common 48.1-9.all [debian-testing-main]
  gedit-dev 48.1-9+b1.amd64 [debian-testing-main]
[...]
$ pkgcli show nano
Package: nano
Version: 9.0-1
Summary: small, friendly text editor inspired by Pico
Description: GNU nano is an easy-to-use text editor originally designed as
 a replacement for Pico, the ncurses-based editor from the non-free mailer
 package Pine.
[...]
URL: https://www.nano-editor.org/
Group: publishing
Installed Size: 2.9 MB
Download Size: 646.0 KB

Search only within package names rather than descriptions: 

$ pkgcli search name python3

Check for updates. refresh updates the metadata, then list-updates reports what s available: 

$ pkgcli refresh && pkgcli list-updates
Loading cache            [ ] 100%
  cme 1.048-1.all [debian-testing-main]
  gir1.2-gdm-1.0 50.1-2.amd64 [debian-testing-main]
  imagemagick 8:7.1.2.24+dfsg1-1.amd64 [debian-testing-main]
  imagemagick-7-common 8:7.1.2.24+dfsg1-1.all [debian-testing-main]
  imagemagick-7.q16 8:7.1.2.24+dfsg1-1.amd64 [debian-testing-main]
  libdlrestrictions1 0.22.0.amd64 [debian-testing-main]
  libfftw3-bin 3.3.11-1.amd64 [debian-testing-main]
  libfftw3-dev 3.3.11-1.amd64 [debian-testing-main]

Explore relationships between packages: 

$ pkgcli list-depends inkscape  # list what inkscape depends on
$ pkgcli list-requiring libappstream5  # list what requires libappstream5

Find the package that provides a capability, here the AV1 GStreamer decoder: 

$ pkgcli what-provides "gstreamer1(decoder-video/x-av1)"
  gstreamer1.0-plugins-bad 1.28.3-1.amd64 [auto:debian-testing-main]

You can also have JSON output for most commands! Attach --json to any query and pipe the result straight into jq. Each line is a self-contained JSON object: 

$ pkgcli --json list-updates   jq -r '.name'
cme
gir1.2-gdm-1.0
imagemagick
imagemagick-7-common
imagemagick-7.q16
libdlrestrictions1
libfftw3-bin
libfftw3-dev
libfftw3-double3

Try it

pkgcli is built by default alongside the rest of PackageKit since PackageKit 1.3.4. If your distribution ships a recent enough PackageKit, it should already be on your PATH. You can read its man page man pkgcli for more information. Feedback, bug reports, and patches are very welcome.

6 April 2026

Thorsten Alteholz: My Debian Activities in March 2026

Debian LTS/ELTS This was my hundred-forty-first month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded or worked on: I also worked on the check-advisories script and proposed a fix for cases where issues would be assigned to the coordinator instead of the person who forgot doing something. I also did some work for a kernel update and packages snapd and ldx on security-master and attended the monthly LTS/ELTS meeting. Last but not least I started to work on gst-plugins-bad1.0 Debian Printing This month I uploaded a new upstream versions: Several packages take care of group lpadmin in their maintainer scripts. With the upload of version 260.1-1 of systemd there is now a central package (systemd systemd-standalone-sysusers systemd-sysusers) that takes care of this. Other dependencies like adduser can now be dropped. This work is generously funded by Freexian! Debian Lomiri This month I continued to work on unifying packaging on Debian and Ubuntu. This makes it easier to work on those packages independent of the used platform. I am also able to upload Debian packages to the corresponding Ubuntu PPA now. A small bug had to be fixed in the python script to allow the initial configuration in Launchpad. This work is generously funded by Fre(i)e Software GmbH! Debian Astro This month I uploaded a new upstream version or a bugfix version of: I also uploaded lots of indi-drivers (libplayerone, libsbig, libricohcamerasdk, indi-asi, indi-eqmod, indi-fishcamp, indi-inovaplx, indi-pentax, indi-playerone, indi-sbig, indi-mi, libahp-xc, indi-aagcloudwatcher, indi-aok, indi-apogee, libapogee3, indi-nightscape, libasi, libinovasdk, libmicam, indi-avalon, indi-beefocus, indi-bresserexos2, indi-dsi, indi-ffmv, indi-fli, indi-gige, info-gphoto, indi-gpsd, indi-gpsnmea, indi-limesdr, indi-maxdomeii, indi-mgen, indi-rtklib, indi-shelyak, indi-starbook, indi-starbookten, indi-talon6, indi-weewx-json, indi-webcam, indi-orion-ssg3, indi-armadillo-playtypus ) to experimental to make progress with the indi-transition. No problems with those drivers appeared and the next step would be the upload of indi version 2.x to unstable. I hope this will happen soon, as new drivers are already waiting in the pipeline. There have been also four packages, that migrated to the official indi package and are no longer needed as 3rdparty drivers (indi-astrolink4, indi-astromechfoc, indi-dreamfocuser, indi-spectracyber). While working on these packages, I thought about testing them. Unfortunately I don t have enough hardware to really check out every package, so I can upload most of them only as is. In case anybody is interested in a better testing coverage and me being able to provide upstream patches, I would be very glad about hardware donations. Debian IoT This month I uploaded a new upstream version or a bugfix version of: Debian Mobcom This month I uploaded a new upstream version or a bugfix version of: misc This month I uploaded a new upstream version or a bugfix version of: I also sponsored the upload of Matomo. Thanks a lot to William for preparing the package.

3 January 2026

Joerg Jaspert: AI Shit, go away; iocaine to the rescue

As a lot of people do, I have some content that is reachable using webbrowsers. There is the password manager Vaultwarden, an instance of Immich, ForgeJo for some personal git repos, my blog and some other random pages here and there. All of this never had been a problem, running a webserver is a relatively simple task, no matter if you use apache2 , nginx or any of the other possibilities. And the things mentioned above bring their own daemon to serve the users.

AI crap And then some idiot somewhere had the idea to ignore every law, every copyright and every normal behaviour and run some shit AI bot. And more idiots followed. And now we have more AI bots than humans generating traffic. And those AI shit crawlers do not respect any limits. robots.txt, slow servers, anything to keep your meager little site up and alive? Them idiots throw more resources onto them to steal content. No sense at all.

iocaine to the rescue So them AI bros want to ignore everything and just fetch the whole internet? Without any consideration if thats even wanted? Or legal? There are people who dislike this. I am one of them, but there are some who got annoyed enough to develop tools to fight the AI craziness. One of those tools is iocaine - it says about itself that it is The deadliest poison known to AI.

Feed AI bots sh*t So you want content? You do not accept any Go away? Then here is content. It is crap, but appearently you don t care. So have fun. What iocaine does is (cite from their webpage) not made for making the Crawlers go away. It is an aggressive defense mechanism that tries its best to take the blunt of the assault, serve them garbage, and keep them off of upstream resources . That is, instead of the expensive webapp using a lot of resources that are basically wasted for nothing, iocaine generates a small static page (with some links back to itself, so the crawler shit stays happy). Which takes a hell of a lot less resource than any fullblown app.

iocaine setup The website has a https://iocaine.madhouse-project.org/documentation/, it is not hard to setup. Still, I had to adjust some things for my setup, as I use [Caddy Docker Proxy ([https://github.com/lucaslorentz/caddy-docker-proxy) nowadays and wanted to keep the config within the docker setup, that is, within the labels.

Caddy container So my container setup for the caddy itself contains the following extra lines: 
    labels:
      caddy_0.email: email@example.com
      caddy_1: (iocaine)
      caddy_1.0_@read: method GET HEAD
      caddy_1.1_reverse_proxy: "@read iocaine:42069"
      "caddy_1.1_reverse_proxy.@fallback": "status 421"
      caddy_1.1_reverse_proxy.handle_response: "@fallback"
This will be translated to the following Caddy config snippet: 
(iocaine)  
        @read method GET HEAD
        reverse_proxy @read iocaine:42069  
                @fallback status 421
                handle_response @fallback

Any container that should be protected by iocaine All the containers that are behind the Caddy reverse proxy can now get protected by iocaine with just one more line in their docker-compose.yaml. So now we have 
   labels:
      caddy: service.example.com
      caddy.reverse_proxy: " upstreams 3000 "
      caddy.import: iocaine
which translates to 
service.example.com  
        import iocaine
        reverse_proxy 172.18.0.6:3000
So with one simple extra label for the docker container I have iocaine activated.

Result? ByeBye (most) AI Bots Looking at the services that got hammered most from those crap bots - deploying this iocaine container and telling Caddy about it solved the problem for me. 98% of the requests from the bots now go to iocaine and no longer hog resources in the actual services. I wish it wouldn t be neccessary to run such tools. But as long as we have shitheads doing the AI hype there is no hope. I wish they all would end up in Jail for all their various stealing they do. And someone with a little more brain left would set things up sensibly, then the AI thing could maybe turn out something good and useful. But currently it is all crap.

8 November 2025

Thorsten Alteholz: My Debian Activities in October 2025

Debian LTS This was my hundred-thirty-sixth month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded or worked on: I also attended the monthly LTS/ELTS meeting. Debian ELTS This month was the eighty-seventh ELTS month. During my allocated time I uploaded or worked on: I also attended the monthly LTS/ELTS meeting. Debian Printing This month I uploaded a new upstream version or a bugfix version of: This work is generously funded by Freexian! Debian Astro This month I uploaded a new upstream version or a bugfix version of: Debian IoT Unfortunately I didn t found any time to work on this topic. Debian Mobcom This month I uploaded a new upstream version or a bugfix version of: misc This month I uploaded a new upstream version or a bugfix version of: On my fight against outdated RFPs, I closed 31 of them in October. I could even close one RFP by uploading the new package gypsy. Meanwhile only 3373 are still open, so don t hesitate to help closing one or another. FTP master This month I accepted 420 and rejected 45 packages. The overall number of packages that got accepted was 423. I would like to remind everybody that in case you don t agree with the removal of a package, please set the moreinfo tag on this bug. This is the only reliable way to prevent processing of that RM-bug. Well, there is a second way, of course you could also achieve this by closing the bug.

9 October 2025

Thorsten Alteholz: My Debian Activities in September 2025

Debian LTS This was my hundred-thirty-fifth month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded or worked on: An upload of spim was not needed, as the corresponding CVE could be marked as ignored. I also started to work on an open-vm-tools and attended the monthly LTS/ELTS meeting. Debian ELTS This month was the eighty-sixth ELTS month. During my allocated time I uploaded or worked on: The CVEs for open-vm-tools could be marked as not-affeceted as the corresponding plugin was not yet available. I also attended the monthly LTS/ELTS meeting. Debian Printing This month I uploaded a new upstream version or a bugfix version of: This work is generously funded by Freexian! Debian Astro This month I uploaded a new upstream version or a bugfix version of: Debian IoT This month I uploaded a new upstream version or a bugfix version of: Debian Mobcom This month I uploaded a new upstream version or a bugfix version of: misc The main topic of this month has been gcc15 and cmake4, so my upload rate was extra high. This month I uploaded a new upstream version or a bugfix version of: I wonder what MBF will happen next, I guess the /var/lock-issue will be a good candidate. On my fight against outdated RFPs, I closed 30 of them in September. Meanwhile only 3397 are still open, so don t hesitate to help closing one or another. FTP master This month I accepted 294 and rejected 28 packages. The overall number of packages that got accepted was 294.

11 June 2025

Freexian Collaborators: Monthly report about Debian Long Term Support, May 2025 (by Roberto C. S nchez)

Like each month, have a look at the work funded by Freexian s Debian LTS offering.

Debian LTS contributors In May, 22 contributors have been paid to work on Debian LTS, their reports are available:
  • Abhijith PA did 8.0h (out of 0.0h assigned and 8.0h from previous period).
  • Adrian Bunk did 26.0h (out of 26.0h assigned).
  • Andreas Henriksson did 1.0h (out of 15.0h assigned and 3.0h from previous period), thus carrying over 17.0h to the next month.
  • Andrej Shadura did 3.0h (out of 10.0h assigned), thus carrying over 7.0h to the next month.
  • Bastien Roucari s did 20.0h (out of 20.0h assigned).
  • Ben Hutchings did 8.0h (out of 20.0h assigned and 4.0h from previous period), thus carrying over 16.0h to the next month.
  • Carlos Henrique Lima Melara did 12.0h (out of 11.0h assigned and 1.0h from previous period).
  • Chris Lamb did 15.5h (out of 0.0h assigned and 15.5h from previous period).
  • Daniel Leidert did 25.0h (out of 26.0h assigned), thus carrying over 1.0h to the next month.
  • Emilio Pozuelo Monfort did 21.0h (out of 16.75h assigned and 11.0h from previous period), thus carrying over 6.75h to the next month.
  • Guilhem Moulin did 11.5h (out of 8.5h assigned and 6.5h from previous period), thus carrying over 3.5h to the next month.
  • Jochen Sprickerhof did 3.5h (out of 8.75h assigned and 17.5h from previous period), thus carrying over 22.75h to the next month.
  • Lee Garrett did 26.0h (out of 12.75h assigned and 13.25h from previous period).
  • Lucas Kanashiro did 20.0h (out of 18.0h assigned and 2.0h from previous period).
  • Markus Koschany did 20.0h (out of 26.25h assigned), thus carrying over 6.25h to the next month.
  • Roberto C. S nchez did 20.75h (out of 24.0h assigned), thus carrying over 3.25h to the next month.
  • Santiago Ruano Rinc n did 15.0h (out of 12.5h assigned and 2.5h from previous period).
  • Sean Whitton did 6.25h (out of 6.0h assigned and 2.0h from previous period), thus carrying over 1.75h to the next month.
  • Sylvain Beucler did 26.25h (out of 26.25h assigned).
  • Thorsten Alteholz did 15.0h (out of 15.0h assigned).
  • Tobias Frost did 12.0h (out of 12.0h assigned).
  • Utkarsh Gupta did 1.0h (out of 15.0h assigned), thus carrying over 14.0h to the next month.

Evolution of the situation In May, we released 54 DLAs. The LTS Team was particularly active in May, publishing a higher than normal number of advisories, as well as helping with a wide range of updates to packages in stable and unstable, plus some other interesting work. We are also pleased to welcome several updates from contributors outside the regular team.
  • Notable security updates:
    • containerd, prepared by Andreas Henriksson, fixes a vulnerability that could cause containers launched as non-root users to be run as root
    • libapache2-mod-auth-openidc, prepared by Moritz Schlarb, fixes a vulnerability which could allow an attacker to crash an Apache web server with libapache2-mod-auth-openidc installed
    • request-tracker4, prepared by Andrew Ruthven, fixes multiple vulnerabilities which could result in information disclosure, cross-site scripting and use of weak encryption for S/MIME emails
    • postgresql-13, prepared by Bastien Roucari s, fixes an application crash vulnerability that could affect the server or applications using libpq
    • dropbear, prepared by Guilhem Moulin, fixes a vulnerability which could potentially result in execution of arbitrary shell commands
    • openjdk-17, openjdk-11, prepared by Thorsten Glaser, fixes several vulnerabilities, which include denial of service, information disclosure or bypass of sandbox restrictions
    • glibc, prepared by Sean Whitton, fixes a privilege escalation vulnerability
  • Notable non-security updates:
    • wireless-regdb, prepared by Ben Hutchings, updates information reflecting changes to radio regulations in many countries
This month s contributions from outside the regular team include the libapache2-mod-auth-openidc update mentioned above, prepared by Moritz Schlarb (the maintainer of the package); the update of request-tracker4, prepared by Andrew Ruthven (the maintainer of the package); and the updates of openjdk-17 and openjdk-11, also noted above, prepared by Thorsten Glaser. Additionally, LTS Team members contributed stable updates of the following packages:
  • rubygems and yelp/yelp-xsl, prepared by Lucas Kanashiro
  • simplesamlphp, prepared by Tobias Frost
  • libbson-xs-perl, prepared by Roberto C. S nchez
  • fossil, prepared by Sylvain Beucler
  • setuptools and mydumper, prepared by Lee Garrett
  • redis and webpy, prepared by Adrian Bunk
  • xrdp, prepared by Abhijith PA
  • tcpdf, prepared by Santiago Ruano Rinc n
  • kmail-account-wizard, prepared by Thorsten Alteholz
Other contributions were also made by LTS Team members to packages in unstable:
  • proftpd-dfsg DEP-8 tests (autopkgtests) were provided to the maintainer, prepared by Lucas Kanashiro
  • a regular upload of libsoup2.4, prepared by Sean Whitton
  • a regular upload of setuptools, prepared by Lee Garrett
Freexian, the entity behind the management of the Debian LTS project, has been working for some time now on the development of an advanced CI platform for Debian-based distributions, called Debusine. Recently, Debusine has reached a level of feature implementation that makes it very usable. Some members of the LTS Team have been using Debusine informally, and during May LTS coordinator Santiago Ruano Rinc n has made a call for the team to help with testing of Debusine, and to help evaluate its suitability for the LTS Team to eventually begin using as the primary mechanism for uploading packages into Debian. Team members who have started using Debusine are providing valuable feedback to the Debusine development team, thus helping to improve the platform for all users. Actually, a number of updates, for both bullseye and bookworm, made during the month of May were handled using Debusine, e.g. rubygems s DLA-4163-1. By the way, if you are a Debian Developer, you can easily test Debusine following the instructions found at https://wiki.debian.org/DebusineDebianNet. DebConf, the annual Debian Conference, is coming up in July and, as is customary each year, the week preceding the conference will feature an event called DebCamp. The DebCamp week provides an opportunity for teams and other interested groups/individuals to meet together in person in the same venue as the conference itself, with the purpose of doing focused work, often called sprints . LTS coordinator Roberto C. S nchez has announced that the LTS Team is planning to hold a sprint primarily focused on the Debian security tracker and the associated tooling used by the LTS Team and the Debian Security Team.

Thanks to our sponsors Sponsors that joined recently are in bold.

16 May 2025

Freexian Collaborators: Monthly report about Debian Long Term Support, April 2025 (by Roberto C. S nchez)

Like each month, have a look at the work funded by Freexian s Debian LTS offering.

Debian LTS contributors In April, 22 contributors have been paid to work on Debian LTS, their reports are available:
  • Adrian Bunk did 56.25h (out of 56.25h assigned).
  • Andreas Henriksson did 15.0h (out of 20.0h assigned), thus carrying over 5.0h to the next month.
  • Andrej Shadura did 10.0h (out of 6.0h assigned and 4.0h from previous period).
  • Bastien Roucari s did 31.5h (out of 31.5h assigned).
  • Ben Hutchings did 8.0h (out of 0.0h assigned and 12.0h from previous period), thus carrying over 4.0h to the next month.
  • Carlos Henrique Lima Melara did 11.0h (out of 12.0h assigned), thus carrying over 1.0h to the next month.
  • Chris Lamb did 18.0h (out of 18.0h assigned).
  • Daniel Leidert did 26.0h (out of 26.0h assigned).
  • Emilio Pozuelo Monfort did 30.0h (out of 39.25h assigned and 0.25h from previous period), thus carrying over 9.5h to the next month.
  • Guilhem Moulin did 8.5h (out of 3.25h assigned and 11.75h from previous period), thus carrying over 6.5h to the next month.
  • Jochen Sprickerhof did 12.5h (out of 20.75h assigned and 9.25h from previous period), thus carrying over 17.5h to the next month.
  • Lee Garrett did 26.25h (out of 7.75h assigned and 31.75h from previous period), thus carrying over 13.25h to the next month.
  • Lucas Kanashiro did 50.0h (out of 0.0h assigned and 52.0h from previous period), thus carrying over 2.0h to the next month.
  • Markus Koschany did 39.5h (out of 39.5h assigned).
  • Roberto C. S nchez did 9.0h (out of 0.0h assigned and 12.0h from previous period), thus carrying over 3.0h to the next month.
  • Santiago Ruano Rinc n did 12.5h (out of 7.5h assigned and 7.5h from previous period), thus carrying over 2.5h to the next month.
  • Sean Whitton did 7.0h (out of 7.0h assigned).
  • Stefano Rivera did 0.5h (out of 0.0h assigned and 10.0h from previous period), thus carrying over 9.5h to the next month.
  • Sylvain Beucler did 39.5h (out of 39.25h assigned and 0.25h from previous period).
  • Thorsten Alteholz did 15.0h (out of 15.0h assigned).
  • Tobias Frost did 12.0h (out of 7.75h assigned and 4.25h from previous period).
  • Utkarsh Gupta did 2.0h (out of 2.0h assigned).

Evolution of the situation In April, we released 46 DLAs.
  • Notable security updates:
    • jetty9, prepared by Markus Koschany, fixes an information disclosure and potential remote code execution vulnerability
    • zabbix, prepared by Tobias Frost, fixes several vulnerabilities, encompassing denial of service, information disclosure or remote code inclusion
    • glibc, prepared by Sean Whitton, fixes a buffer overflow vulnerability
  • Notable non-security updates:
    • tzdata, prepared by Emilio Pozuelo Monfort, brings the latest timezone database release
    • php-horde-editor and php-horde-imp, prepared by Sylvain Beucler, have been updated to switch from CKEditor v3, which is EOL, to CKEditor v4; this builds upon work done last month by Sylvain and Bastien for the complete removal of ckeditor3
    • distro-info-data, prepared by Stefano Rivera, adds information concerning future Debian and Ubuntu releases
The LTS team continues to welcome the collaboration of maintainers and other interested parties from outside the regular team. In April, we had external updates contributed by: Yadd - lemonldap-ng and Moritz Schlarb - libapache2-mod-auth-openidc A point release of the current stable Debian 12 (codename bookworm ) is planned for mid-May and several LTS contributors have prepared packages for this update, many of them prepared in conjunction with related LTS updates of the same packages:
  • glib2.0, haproxy, imagemagick, poppler, and python-h11, prepared by Adrian Bunk
  • rubygems, prepared by Lucas Kanashiro
  • ruby3.1 (in collaboration with Lucas Kanashiro), twitter-bootstrap3, twitterboot-strap4, wpa, and erlang, prepared by Bastien Roucari s (corresponding updates of twitter-bootstrap3 and twitter-bootstrap4 were also uploaded to Debian unstable)
  • abseil, prepared by Tobias Frost (a corresponding update was also uploaded to Debian unstable)
  • vips, prepared by Guilhem Moulin
Additional updates of ruby3.3 and rubygems were prepared for Debian unstable by Lucas Kanashiro. And finally, a highlight of our continued commitment to enhancing long term support efforts in upstream projects. Freexian, as the primary entity behind the management and execution of the LTS project, has partnered with Invisible Things Lab to extend the upstream security support of Xen 4.17, which is shipped in Debian 12 bookworm (the current stable release). This partnership will result in significantly improved lifecycle support for users of Xen on bookworm, and members of the LTS team will play a part in this endeavour. The Freexian announcement has additional details.

Thanks to our sponsors Sponsors that joined recently are in bold.

12 April 2025

Kalyani Kenekar: Nextcloud Installation HowTo: Secure Your Data with a Private Cloud

Logo NGinx Nextcloud is an open-source software suite that enables you to set up and manage your own cloud storage and collaboration platform. It offers a range of features similar to popular cloud services like Google Drive or Dropbox but with the added benefit of complete control over your data and the server where it s hosted. I wanted to have a look at Nextcloud and the steps to setup a own instance with a PostgreSQL based database together with NGinx as the webserver to serve the WebUI. Before doing a full productive setup I wanted to play around locally with all the needed steps and worked out all the steps within KVM machine. While doing this I wrote down some notes to mostly document for myself what I need to do to get a Nextcloud installation running and usable. So this manual describes how to setup a Nextcloud installation on Debian 12 Bookworm based on NGinx and PostgreSQL.

Nextcloud Installation

Install PHP and PHP extensions for Nextcloud Nextcloud is basically a PHP application so we need to install PHP packages to get it working in the end. The following steps are based on the upstream documentation about how to install a own Nextcloud instance. Installing the virtual package package php on a Debian Bookworm system would pull in the depending meta package php8.2. This package itself would then pull also the package libapache2-mod-php8.2 as an dependency which then would pull in also the apache2 webserver as a depending package. This is something I don t wanted to have as I want to use NGinx that is already installed on the system instead. To get this we need to explicitly exclude the package libapache2-mod-php8.2 from the list of packages which we want to install, to achieve this we have to append a hyphen - at the end of the package name, so we need to use libapache2-mod-php8.2- within the package list that is telling apt to ignore this package as an dependency. I ended up with this call to get all needed dependencies installed. 
$ sudo apt install php php-cli php-fpm php-json php-common php-zip \
  php-gd php-intl php-curl php-xml php-mbstring php-bcmath php-gmp \
  php-pgsql libapache2-mod-php8.2-
  • Check php version (optional step) $ php -v 
PHP 8.2.28 (cli) (built: Mar 13 2025 18:21:38) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.2.28, Copyright (c) Zend Technologies
    with Zend OPcache v8.2.28, Copyright (c), by Zend Technologies
  • After installing all the packages, edit the php.ini file: $ sudo vi /etc/php/8.2/fpm/php.ini
  • Change the following settings per your requirements: 
max_execution_time = 300
memory_limit = 512M
post_max_size = 128M
upload_max_filesize = 128M
  • To make these settings effective, restart the php-fpm service $ sudo systemctl restart php8.2-fpm

Install PostgreSQL, Create a database and user This manual assumes we will use a PostgreSQL server on localhost, if you have a server instance on some remote site you can skip the installation step here. $ sudo apt install postgresql postgresql-contrib postgresql-client
  • Check version after installation (optinal step): $ sudo -i -u postgres $ psql -version
  • This output will be seen: psql (15.12 (Debian 15.12-0+deb12u2))
  • Exit the PSQL shell by using the command \q. postgres=# \q
  • Exit the CLI of the postgres user: postgres@host:~$ exit

Create a PostgreSQL Database and User:
  1. Create a new PostgreSQL user (Use a strong password!): $ sudo -u postgres psql -c "CREATE USER nextcloud_user PASSWORD '1234';"
  2. Create new database and grant access: $ sudo -u postgres psql -c "CREATE DATABASE nextcloud_db WITH OWNER nextcloud_user ENCODING=UTF8;"
  3. (Optional) Check if we now can connect to the database server and the database in detail (you will get a question about the password for the database user!). If this is not working it makes no sense to proceed further! We need to fix first the access then! $ psql -h localhost -U nextcloud_user -d nextcloud_db or $ psql -h 127.0.0.1 -U nextcloud_user -d nextcloud_db
  • Log out from postgres shell using the command \q.

Download and install Nextcloud
  • Use the following command to download the latest version of Nextcloud: $ wget https://download.nextcloud.com/server/releases/latest.zip
  • Extract file into the folder /var/www/html with the following command: $ sudo unzip latest.zip -d /var/www/html
  • Change ownership of the /var/www/html/nextcloud directory to www-data. $ sudo chown -R www-data:www-data /var/www/html/nextcloud

Configure NGinx for Nextcloud to use a certificate In case you want to use self signed certificate, e.g. if you play around to setup Nextcloud locally for testing purposes you can do the following steps.
  • Generate the private key and certificate: $ sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout nextcloud.key -out nextcloud.crt $ sudo cp nextcloud.crt /etc/ssl/certs/ && sudo cp nextcloud.key /etc/ssl/private/
  • If you want or need to use the service of Let s Encrypt (or similar) drop the step above and create your required key data by using this command: $ sudo certbot --nginx -d nextcloud.your-domain.com You will need to adjust the path to the key and certificate in the next step!
  • Change the NGinx configuration: $ sudo vi /etc/nginx/sites-available/nextcloud.conf
  • Add the following snippet into the file and save it. 
# /etc/nginx/sites-available/nextcloud.conf
upstream php-handler  
    #server 127.0.0.1:9000;
    server unix:/run/php/php8.2-fpm.sock;
 

# Set the  immutable  cache control options only for assets with a cache
# busting  v  argument

map $arg_v $asset_immutable  
    "" "";
    default ", immutable";
 

server  
    listen 80;
    listen [::]:80;
    # Adjust this to the correct server name!
    server_name nextcloud.local;

    # Prevent NGinx HTTP Server Detection
    server_tokens off;

    # Enforce HTTPS
    return 301 https://$server_name$request_uri;
 

server  
    listen 443      ssl http2;
    listen [::]:443 ssl http2;
    # Adjust this to the correct server name!
    server_name nextcloud.local;

    # Path to the root of your installation
    root /var/www/html/nextcloud;

    # Use Mozilla's guidelines for SSL/TLS settings
    # https://mozilla.github.io/server-side-tls/ssl-config-generator/
    # Adjust the usage and paths of the correct key data! E.g. it you want to use Let's Encrypt key material!
    ssl_certificate /etc/ssl/certs/nextcloud.crt;
    ssl_certificate_key /etc/ssl/private/nextcloud.key;
    # ssl_certificate /etc/letsencrypt/live/nextcloud.your-domain.com/fullchain.pem; 
    # ssl_certificate_key /etc/letsencrypt/live/nextcloud.your-domain.com/privkey.pem;

    # Prevent NGinx HTTP Server Detection
    server_tokens off;

    # HSTS settings
    # WARNING: Only add the preload option once you read about
    # the consequences in https://hstspreload.org/. This option
    # will add the domain to a hardcoded list that is shipped
    # in all major browsers and getting removed from this list
    # could take several months.
    #add_header Strict-Transport-Security "max-age=15768000; includeSubDomains; preload" always;

    # set max upload size and increase upload timeout:
    client_max_body_size 512M;
    client_body_timeout 300s;
    fastcgi_buffers 64 4K;

    # Enable gzip but do not remove ETag headers
    gzip on;
    gzip_vary on;
    gzip_comp_level 4;
    gzip_min_length 256;
    gzip_proxied expired no-cache no-store private no_last_modified no_etag auth;
    gzip_types application/atom+xml text/javascript application/javascript application/json application/ld+json application/manifest+json application/rss+xml application/vnd.geo+json application/vnd.ms-fontobject application/wasm application/x-font-ttf application/x-web-app-manifest+json application/xhtml+xml application/xml font/opentype image/bmp image/svg+xml image/x-icon text/cache-manifest text/css text/plain text/vcard text/vnd.rim.location.xloc text/vtt text/x-component text/x-cross-domain-policy;

    # Pagespeed is not supported by Nextcloud, so if your server is built
    # with the  ngx_pagespeed  module, uncomment this line to disable it.
    #pagespeed off;

    # The settings allows you to optimize the HTTP2 bandwidth.
    # See https://blog.cloudflare.com/delivering-http-2-upload-speed-improvements/
    # for tuning hints
    client_body_buffer_size 512k;

    # HTTP response headers borrowed from Nextcloud  .htaccess 
    add_header Referrer-Policy                   "no-referrer"       always;
    add_header X-Content-Type-Options            "nosniff"           always;
    add_header X-Frame-Options                   "SAMEORIGIN"        always;
    add_header X-Permitted-Cross-Domain-Policies "none"              always;
    add_header X-Robots-Tag                      "noindex, nofollow" always;
    add_header X-XSS-Protection                  "1; mode=block"     always;

    # Remove X-Powered-By, which is an information leak
    fastcgi_hide_header X-Powered-By;

    # Set .mjs and .wasm MIME types
    # Either include it in the default mime.types list
    # and include that list explicitly or add the file extension
    # only for Nextcloud like below:
    include mime.types;
    types  
        text/javascript js mjs;
        application/wasm wasm;
     

    # Specify how to handle directories -- specifying  /index.php$request_uri 
    # here as the fallback means that NGinx always exhibits the desired behaviour
    # when a client requests a path that corresponds to a directory that exists
    # on the server. In particular, if that directory contains an index.php file,
    # that file is correctly served; if it doesn't, then the request is passed to
    # the front-end controller. This consistent behaviour means that we don't need
    # to specify custom rules for certain paths (e.g. images and other assets,
    #  /updater ,  /ocs-provider ), and thus
    #  try_files $uri $uri/ /index.php$request_uri 
    # always provides the desired behaviour.
    index index.php index.html /index.php$request_uri;

    # Rule borrowed from  .htaccess  to handle Microsoft DAV clients
    location = /  
        if ( $http_user_agent ~ ^DavClnt )  
            return 302 /remote.php/webdav/$is_args$args;
         
     

    location = /robots.txt  
        allow all;
        log_not_found off;
        access_log off;
     

    # Make a regex exception for  /.well-known  so that clients can still
    # access it despite the existence of the regex rule
    #  location ~ /(\. autotest ...)  which would otherwise handle requests
    # for  /.well-known .
    location ^~ /.well-known  
        # The rules in this block are an adaptation of the rules
        # in  .htaccess  that concern  /.well-known .

        location = /.well-known/carddav   return 301 /remote.php/dav/;  
        location = /.well-known/caldav    return 301 /remote.php/dav/;  

        location /.well-known/acme-challenge      try_files $uri $uri/ =404;  
        location /.well-known/pki-validation      try_files $uri $uri/ =404;  

        # Let Nextcloud's API for  /.well-known  URIs handle all other
        # requests by passing them to the front-end controller.
        return 301 /index.php$request_uri;
     

    # Rules borrowed from  .htaccess  to hide certain paths from clients
    location ~ ^/(?:build tests config lib 3rdparty templates data)(?:$ /)    return 404;  
    location ~ ^/(?:\. autotest occ issue indie db_ console)                  return 404;  

    # Ensure this block, which passes PHP files to the PHP process, is above the blocks
    # which handle static assets (as seen below). If this block is not declared first,
    # then NGinx will encounter an infinite rewriting loop when it prepend  /index.php 
    # to the URI, resulting in a HTTP 500 error response.
    location ~ \.php(?:$ /)  
        # Required for legacy support
        rewrite ^/(?!index remote public cron core\/ajax\/update status ocs\/v[12] updater\/.+ ocs-provider\/.+ .+\/richdocumentscode(_arm64)?\/proxy) /index.php$request_uri;

        fastcgi_split_path_info ^(.+?\.php)(/.*)$;
        set $path_info $fastcgi_path_info;

        try_files $fastcgi_script_name =404;

        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_param PATH_INFO $path_info;
        fastcgi_param HTTPS on;

        fastcgi_param modHeadersAvailable true;         # Avoid sending the security headers twice
        fastcgi_param front_controller_active true;     # Enable pretty urls
        fastcgi_pass php-handler;

        fastcgi_intercept_errors on;
        fastcgi_request_buffering off;

        fastcgi_max_temp_file_size 0;
     

    # Serve static files
    location ~ \.(?:css js mjs svg gif png jpg ico wasm tflite map ogg flac)$  
        try_files $uri /index.php$request_uri;
        # HTTP response headers borrowed from Nextcloud  .htaccess 
        add_header Cache-Control                     "public, max-age=15778463$asset_immutable";
        add_header Referrer-Policy                   "no-referrer"       always;
        add_header X-Content-Type-Options            "nosniff"           always;
        add_header X-Frame-Options                   "SAMEORIGIN"        always;
        add_header X-Permitted-Cross-Domain-Policies "none"              always;
        add_header X-Robots-Tag                      "noindex, nofollow" always;
        add_header X-XSS-Protection                  "1; mode=block"     always;
        access_log off;     # Optional: Don't log access to assets
     

    location ~ \.woff2?$  
        try_files $uri /index.php$request_uri;
        expires 7d;         # Cache-Control policy borrowed from  .htaccess 
        access_log off;     # Optional: Don't log access to assets
     

    # Rule borrowed from  .htaccess 
    location /remote  
        return 301 /remote.php$request_uri;
     

    location /  
        try_files $uri $uri/ /index.php$request_uri;
  • Symlink configuration site available to site enabled. $ ln -s /etc/nginx/sites-available/nextcloud.conf /etc/nginx/sites-enabled/
  • Restart NGinx and access the URI in the browser.
  • Go through the installation of Nextcloud.
  • The user data on the installation dialog should point e.g to administrator or similar, that user will become administrative access rights in Nextcloud!
  • To adjust the database connection detail you have to edit the file $install_folder/config/config.php. Means here in the example within this post you would need to modify /var/www/html/nextcloud/config/config.php to control or change the database connection. 
---%<---
    'dbname' => 'nextcloud_db',
    'dbhost' => 'localhost', #(Or your remote PostgreSQL server address if you have.)
    'dbport' => '',
    'dbtableprefix' => 'oc_',
    'dbuser' => 'nextcloud_user',
    'dbpassword' => '1234', #(The password you set for database user.)
--->%---
After the installation and setup of the Nextcloud PHP application there are more steps to be done. Have a look into the WebUI what you will need to do as additional steps like create a cronjob or tuning of some more PHP configurations. If you ve done all things correct you should see a login page similar to this: Login Page of your Nextcloud instance

Optional other steps for more enhanced configuration modifications

Move the data folder to somewhere else The data folder is the root folder for all user content. By default it is located in $install_folder/data, so in our case here it is in /var/www/html/nextcloud/data.
  • Move the data directory outside the web server document root. $ sudo mv /var/www/html/nextcloud/data /var/nextcloud_data
  • Ensure access permissions, mostly not needed if you move the folder. $ sudo chown -R www-data:www-data /var/nextcloud_data $ sudo chown -R www-data:www-data /var/www/html/nextcloud/
  • Update the Nextcloud configuration:
    1. Open the config/config.php file of your Nextcloud installation. $ sudo vi /var/www/html/nextcloud/config/config.php
    2. Update the datadirectory parameter to point to the new location of your data directory. 
  ---%<---
     'datadirectory' => '/var/nextcloud_data'
  --->%---
  • Restart NGinx service: $ sudo systemctl restart nginx

Make the installation available for multiple FQDNs on the same server
  • Adjust the Nextcloud configuration to listen and accept requests for different domain names. Configure and adjust the key trusted_domains accordingly. $ sudo vi /var/www/html/nextcloud/config/config.php 
  ---%<---
    'trusted_domains' => 
    array (
      0 => 'domain.your-domain.com',
      1 => 'domain.other-domain.com',
    ),
  --->%---
  • Create and adjust the needed site configurations for the webserver.
  • Restart the NGinx unit.

An error message about .ocdata might occur
  • .ocdata is not found inside the data directory
    • Create file using touch and set necessary permissions. $ sudo touch /var/nextcloud_data/.ocdata $ sudo chown -R www-data:www-data /var/nextcloud_data/

The password for the administrator user is unknown
  1. Log in to your server:
    • SSH into the server where your PostgreSQL database is hosted.
  2. Switch to the PostgreSQL user:
    • $ sudo -i -u postgres
  3. Access the PostgreSQL command line
    • psql
  4. List the databases: (If you re unsure which database is being used by Nextcloud, you can list all the databases by the list command.)
    • \l
  5. Switch to the Nextcloud database:
    • Switch to the specific database that Nextcloud is using.
    • \c nextclouddb
  6. Reset the password for the Nextcloud database user:
    • ALTER USER nextcloud_user WITH PASSWORD 'new_password';
  7. Exit the PostgreSQL command line:
    • \q
  8. Verify Database Configuration:
    • Check the database connection details in the config.php file to ensure they are correct. sudo vi /var/www/html/nextcloud/config/config.php
    • Replace nextcloud_db, nextcloud_user, and your_password with your actual database name, user, and password. 
---%<---
    'dbname' => 'nextcloud_db',
    'dbhost' => 'localhost', #(or your PostgreSQL server address)
    'dbport' => '',
    'dbtableprefix' => 'oc_',
    'dbuser' => 'nextcloud_user',
    'dbpassword' => '1234', #(The password you set for nextcloud_user.)
--->%---
  1. Restart NGinx and access the UI through the browser.

11 April 2025

Reproducible Builds: Reproducible Builds in March 2025

Welcome to the third report in 2025 from the Reproducible Builds project. Our monthly reports outline what we ve been up to over the past month, and highlight items of news from elsewhere in the increasingly-important area of software supply-chain security. As usual, however, if you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. Table of contents:
  1. Debian bookworm live images now fully reproducible from their binary packages
  2. How NixOS and reproducible builds could have detected the xz backdoor
  3. LWN: Fedora change aims for 99% package reproducibility
  4. Python adopts PEP standard for specifying package dependencies
  5. OSS Rebuild real-time validation and tooling improvements
  6. SimpleX Chat server components now reproducible
  7. Three new scholarly papers
  8. Distribution roundup
  9. An overview of Supply Chain Attacks on Linux distributions
  10. diffoscope & strip-nondeterminism
  11. Website updates
  12. Reproducibility testing framework
  13. Upstream patches

Debian bookworm live images now fully reproducible from their binary packages Roland Clobus announced on our mailing list this month that all the major desktop variants (ie. Gnome, KDE, etc.) can be reproducibly created for Debian bullseye, bookworm and trixie from their (pre-compiled) binary packages. Building reproducible Debian live images does not require building from reproducible source code, but this is still a remarkable achievement. Some large proportion of the binary packages that comprise these live images can (and were) built reproducibly, but live image generation works at a higher level. (By contrast, full or end-to-end reproducibility of a bootable OS image will, in time, require both the compile-the-packages the build-the-bootable-image stages to be reproducible.) Nevertheless, in response, Roland s announcement generated significant congratulations as well as some discussion regarding the finer points of the terms employed: a full outline of the replies can be found here. The news was also picked up by Linux Weekly News (LWN) as well as to Hacker News.

How NixOS and reproducible builds could have detected the xz backdoor Julien Malka aka luj published an in-depth blog post this month with the highly-stimulating title How NixOS and reproducible builds could have detected the xz backdoor for the benefit of all . Starting with an dive into the relevant technical details of the XZ Utils backdoor, Julien s article goes on to describe how we might avoid the xz catastrophe in the future by building software from trusted sources and building trust into untrusted release tarballs by way of comparing sources and leveraging bitwise reproducibility, i.e. applying the practices of Reproducible Builds. The article generated significant discussion on Hacker News as well as on Linux Weekly News (LWN).

LWN: Fedora change aims for 99% package reproducibility Linux Weekly News (LWN) contributor Joe Brockmeier has published a detailed round-up on how Fedora change aims for 99% package reproducibility. The article opens by mentioning that although Debian has been working toward reproducible builds for more than a decade , the Fedora project has now:
progressed far enough that the project is now considering a change proposal for the Fedora 43 development cycle, expected to be released in October, with a goal of making 99% of Fedora s package builds reproducible. So far, reaction to the proposal seems favorable and focused primarily on how to achieve the goal with minimal pain for packagers rather than whether to attempt it.
The Change Proposal itself is worth reading:
Over the last few releases, we [Fedora] changed our build infrastructure to make package builds reproducible. This is enough to reach 90%. The remaining issues need to be fixed in individual packages. After this Change, package builds are expected to be reproducible. Bugs will be filed against packages when an irreproducibility is detected. The goal is to have no fewer than 99% of package builds reproducible.
Further discussion can be found on the Fedora mailing list as well as on Fedora s Discourse instance.

Python adopts PEP standard for specifying package dependencies Python developer Brett Cannon reported on Fosstodon that PEP 751 was recently accepted. This design document has the purpose of describing a file format to record Python dependencies for installation reproducibility . As the abstract of the proposal writes:
This PEP proposes a new file format for specifying dependencies to enable reproducible installation in a Python environment. The format is designed to be human-readable and machine-generated. Installers consuming the file should be able to calculate what to install without the need for dependency resolution at install-time.
The PEP, which itself supersedes PEP 665, mentions that there are at least five well-known solutions to this problem in the community .

OSS Rebuild real-time validation and tooling improvements OSS Rebuild aims to automate rebuilding upstream language packages (e.g. from PyPI, crates.io, npm registries) and publish signed attestations and build definitions for public use. OSS Rebuild is now attempting rebuilds as packages are published, shortening the time to validating rebuilds and publishing attestations. Aman Sharma contributed classifiers and fixes for common sources of non-determinism in JAR packages. Improvements were also made to some of the core tools in the project:
  • timewarp for simulating the registry responses from sometime in the past.
  • proxy for transparent interception and logging of network activity.
  • and stabilize, yet another nondeterminism fixer.

SimpleX Chat server components now reproducible SimpleX Chat is a privacy-oriented decentralised messaging platform that eliminates user identifiers and metadata, offers end-to-end encryption and has a unique approach to decentralised identity. Starting from version 6.3, however, Simplex has implemented reproducible builds for its server components. This advancement allows anyone to verify that the binaries distributed by SimpleX match the source code, improving transparency and trustworthiness.

Three new scholarly papers Aman Sharma of the KTH Royal Institute of Technology of Stockholm, Sweden published a paper on Build and Runtime Integrity for Java (PDF). The paper s abstract notes that Software Supply Chain attacks are increasingly threatening the security of software systems and goes on to compare build- and run-time integrity:
Build-time integrity ensures that the software artifact creation process, from source code to compiled binaries, remains untampered. Runtime integrity, on the other hand, guarantees that the executing application loads and runs only trusted code, preventing dynamic injection of malicious components.
Aman s paper explores solutions to safeguard Java applications and proposes some novel techniques to detect malicious code injection. A full PDF of the paper is available.
In addition, Hamed Okhravi and Nathan Burow of Massachusetts Institute of Technology (MIT) Lincoln Laboratory along with Fred B. Schneider of Cornell University published a paper in the most recent edition of IEEE Security & Privacy on Software Bill of Materials as a Proactive Defense:
The recently mandated software bill of materials (SBOM) is intended to help mitigate software supply-chain risk. We discuss extensions that would enable an SBOM to serve as a basis for making trust assessments thus also serving as a proactive defense.
A full PDF of the paper is available.
Lastly, congratulations to Giacomo Benedetti of the University of Genoa for publishing their PhD thesis. Titled Improving Transparency, Trust, and Automation in the Software Supply Chain, Giacomo s thesis:
addresses three critical aspects of the software supply chain to enhance security: transparency, trust, and automation. First, it investigates transparency as a mechanism to empower developers with accurate and complete insights into the software components integrated into their applications. To this end, the thesis introduces SUNSET and PIP-SBOM, leveraging modeling and SBOMs (Software Bill of Materials) as foundational tools for transparency and security. Second, it examines software trust, focusing on the effectiveness of reproducible builds in major ecosystems and proposing solutions to bolster their adoption. Finally, it emphasizes the role of automation in modern software management, particularly in ensuring user safety and application reliability. This includes developing a tool for automated security testing of GitHub Actions and analyzing the permission models of prominent platforms like GitHub, GitLab, and BitBucket.

Distribution roundup In Debian this month:
The IzzyOnDroid Android APK repository reached another milestone in March, crossing the 40% coverage mark specifically, more than 42% of the apps in the repository is now reproducible Thanks to funding by NLnet/Mobifree, the project was also to put more time into their tooling. For instance, developers can now run easily their own verification builder in less than 5 minutes . This currently supports Debian-based systems, but support for RPM-based systems is incoming. Future work in the pipeline, including documentation, guidelines and helpers for debugging.
Fedora developer Zbigniew J drzejewski-Szmek announced a work-in-progress script called fedora-repro-build which attempts to reproduce an existing package within a Koji build environment. Although the project s README file lists a number of fields will always or almost always vary (and there are a non-zero list of other known issues), this is an excellent first step towards full Fedora reproducibility (see above for more information).
Lastly, in openSUSE news, Bernhard M. Wiedemann posted another monthly update for his work there.

An overview of Supply Chain Attacks on Linux distributions Fenrisk, a cybersecurity risk-management company, has published a lengthy overview of Supply Chain Attacks on Linux distributions. Authored by Maxime Rinaudo, the article asks:
[What] would it take to compromise an entire Linux distribution directly through their public infrastructure? Is it possible to perform such a compromise as simple security researchers with no available resources but time?

diffoscope & strip-nondeterminism diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb made the following changes, including preparing and uploading versions 290, 291, 292 and 293 and 293 to Debian:
  • Bug fixes:
    • file(1) version 5.46 now returns XHTML document for .xhtml files such as those found nested within our .epub tests. [ ]
    • Also consider .aar files as APK files, at least for the sake of diffoscope. [ ]
    • Require the new, upcoming, version of file(1) and update our quine-related testcase. [ ]
  • Codebase improvements:
    • Ensure all calls to our_check_output in the ELF comparator have the potential CalledProcessError exception caught. [ ][ ]
    • Correct an import masking issue. [ ]
    • Add a missing subprocess import. [ ]
    • Reformat openssl.py. [ ]
    • Update copyright years. [ ][ ][ ]
In addition, Ivan Trubach contributed a change to ignore the st_size metadata entry for directories as it is essentially arbitrary and introduces unnecessary or even spurious changes. [ ]

Website updates Once again, there were a number of improvements made to our website this month, including:

Reproducibility testing framework The Reproducible Builds project operates a comprehensive testing framework running primarily at tests.reproducible-builds.org in order to check packages and other artifacts for reproducibility. In March, a number of changes were made by Holger Levsen, including:
  • reproduce.debian.net-related:
    • Add links to two related bugs about buildinfos.debian.net. [ ]
    • Add an extra sync to the database backup. [ ]
    • Overhaul description of what the service is about. [ ][ ][ ][ ][ ][ ]
    • Improve the documentation to indicate that need to fix syncronisation pipes. [ ][ ]
    • Improve the statistics page by breaking down output by architecture. [ ]
    • Add a copyright statement. [ ]
    • Add a space after the package name so one can search for specific packages more easily. [ ]
    • Add a script to work around/implement a missing feature of debrebuild. [ ]
  • Misc:
    • Run debian-repro-status at the end of the chroot-install tests. [ ][ ]
    • Document that we have unused diskspace at Ionos. [ ]
In addition:
  • James Addison made a number of changes to the reproduce.debian.net homepage. [ ][ ].
  • Jochen Sprickerhof updated the statistics generation to catch No space left on device issues. [ ]
  • Mattia Rizzolo added a better command to stop the builders [ ] and fixed the reStructuredText syntax in the README.infrastructure file. [ ]
And finally, node maintenance was performed by Holger Levsen [ ][ ][ ] and Mattia Rizzolo [ ][ ].

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:
Finally, 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:

28 February 2025

Petter Reinholdtsen: Brushing up on old packages in Xiph and Debian

Since my motivation boost in the beginning of the month caused me to wrap up a new release of liboggz, I have used the same boost to wrap up new editions of libfishsound, liboggplay and libkate too. These have been tagged in upstream git, but not yet published on the Xiph download location. I am waiting for someone with access to have time to move the tarballs there, I hope it will happen in a few days. The same is the case for a minor update of liboggz too. As I was looking at Xiph packages lacking updates, it occurred to me that there are packages in Debian that have not received a new upload in a long time. Looking for a way to identify them, I came across the ltnu script from the devscripts package. It can sort by last update, packages maintained by a single user/group, and is useful to figure out which packages a single maintainer should have a look at. But I wanted a archive wide summary. Based on the UDD SQL query used by ltnu, I ended up with the following command: 
#!/bin/sh
env PGPASSWORD=udd-mirror psql --host=udd-mirror.debian.net --user=udd-mirror udd --command="
select source,
       max(version) as ver,
       max(date) as uploaded
from upload_history
where distribution='unstable' and
      source in (select source
                 from sources
                 where release='sid')
group by source
order by max(date) asc
limit 50;"
This will sort all source packages in Debian by upload date, and list the 50 oldest ones. The end result is a list of packages I suspect could use some attention: 
           source                        ver                    uploaded        
-----------------------------+-------------------------+------------------------
 xserver-xorg-video-ivtvdev    1.1.2-1                   2011-02-09 22:26:27+00
 dynamite                      0.1.1-2                   2011-04-30 16:47:20+00
 xkbind                        2010.05.20-1              2011-05-02 22:48:05+00
 libspctag                     0.2-1                     2011-09-22 18:47:07+00
 gromit                        20041213-9                2011-11-13 21:02:56+00
 s3switch                      0.1-1                     2011-11-22 15:47:40+00
 cd5                           0.1-3                     2011-12-07 21:19:05+00
 xserver-xorg-video-glide      1.2.0-1                   2011-12-30 16:50:48+00
 blahtexml                     0.9-1.1                   2012-04-25 11:32:11+00
 aggregate                     1.6-7                     2012-05-01 00:47:11+00
 rtfilter                      1.1-4                     2012-05-11 12:50:00+00
 sic                           1.1-5                     2012-05-11 19:10:31+00
 kbdd                          0.6-4                     2012-05-12 07:33:32+00
 logtop                        0.4.3-1                   2012-06-05 23:04:20+00
 gbemol                        0.3.2-2                   2012-06-26 17:03:11+00
 pidgin-mra                    20100304-1                2012-06-29 23:07:41+00
 mumudvb                       1.7.1-1                   2012-06-30 09:12:14+00
 libdr-sundown-perl            0.02-1                    2012-08-18 10:00:07+00
 ztex-bmp                      20120314-2                2012-08-18 19:47:55+00
 display-dhammapada            1.0-0.1                   2012-12-19 12:02:32+00
 eot-utils                     1.1-1                     2013-02-19 17:02:28+00
 multiwatch                    1.0.0-rc1+really1.0.0-1   2013-02-19 17:02:35+00
 pidgin-latex                  1.5.0-1                   2013-04-04 15:03:43+00
 libkeepalive                  0.2-1                     2013-04-08 22:00:07+00
 dfu-programmer                0.6.1-1                   2013-04-23 13:32:32+00
 libb64                        1.2-3                     2013-05-05 21:04:51+00
 i810switch                    0.6.5-7.1                 2013-05-10 13:03:18+00
 premake4                      4.3+repack1-2             2013-05-31 12:48:51+00
 unagi                         0.3.4-1                   2013-06-05 11:19:32+00
 mod-vhost-ldap                2.4.0-1                   2013-07-12 07:19:00+00
 libapache2-mod-ldap-userdir   1.1.19-2.1                2013-07-12 21:22:48+00
 w9wm                          0.4.2-8                   2013-07-18 11:49:10+00
 vish                          0.0.20130812-1            2013-08-12 21:10:37+00
 xfishtank                     2.5-1                     2013-08-20 17:34:06+00
 wap-wml-tools                 0.0.4-7                   2013-08-21 16:19:10+00
 ttysnoop                      0.12d-6                   2013-08-24 17:33:09+00
 libkaz                        1.21-2                    2013-09-02 16:00:10+00
 rarpd                         0.981107-9                2013-09-02 19:48:24+00
 libimager-qrcode-perl         0.033-1.2                 2013-09-04 21:06:31+00
 dov4l                         0.9+repack-1              2013-09-22 19:33:25+00
 textdraw                      0.2+ds-0+nmu1             2013-10-07 21:25:03+00
 gzrt                          0.8-1                     2013-10-08 06:33:13+00
 away                          0.9.5+ds-0+nmu2           2013-10-25 01:18:18+00
 jshon                         20131010-1                2013-11-30 00:00:11+00
 libstar-parser-perl           0.59-4                    2013-12-23 21:50:43+00
 gcal                          3.6.3-3                   2013-12-29 18:33:29+00
 fonts-larabie                 1:20011216-5              2014-01-02 21:20:49+00
 ccd2iso                       0.3-4                     2014-01-28 06:33:35+00
 kerneltop                     0.91-1                    2014-02-04 12:03:30+00
 vera++                        1.2.1-2                   2014-02-04 21:21:37+00
(50 rows)
So there are 8 packages last uploaded to unstable in 2011, 12 packages in 2012 and 26 packages in 2013. I suspect their maintainers need help and we should all offer our assistance. I already contacted two of them and hope the rest of the Debian community will chip in to help too. We should ensure any Debian specific patches are passed upstream if they still exist, that the package is brought up to speed with the latest Debian policy, as well as ensure the source can built with the current compiler set 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.

31 December 2024

Fran ois Marier: Monitoring and Time-Shifting YouTube Podcasts

While most podcasts are available on multiple platforms and either offer an RSS feed or have one that can be discovered, some are only available in the form of a YouTube channel. Thankfully, it's possible to both monitor them for new episodes (i.e. new videos), and time-shift the audio for later offline listening. Subscribing to a channel via RSS is possible thanks to the built-in, but not easily discoverable, RSS feeds. See these instructions for how to do it. As an example, the RSS feed for the official Government of BC channel is https://www.youtube.com/feeds/videos.xml?channel_id=UC6n9tFQOVepHP3TIeYXnhSA. When it comes to downloading the audio, the most reliable tool I have found is yt-dlp. Since the exact arguments needed to download just the audio as an MP3 are a bit of a mouthful, I wrote a wrapper script which also does a few extra things: If you find that script handy, you may also want to check out the script I have in the same GitHub repo to turn arbitrary video files into a podcast.

29 November 2024

Dirk Eddelbuettel: RcppAPT 0.0.10: Maintenance

A new version of the RcppAPT package arrived on CRAN earlier today. RcppAPT connects R to the C++ library behind the awesome apt, apt-get, apt-cache, commands (and their cache) which powering Debian, Ubuntu and other derivative distributions. RcppAPT allows you to query the (Debian or Ubuntu) package dependency graph at will, with build-dependencies (if you have deb-src entries), reverse dependencies, and all other goodies. See the vignette and examples for illustrations. This release moves the C++ compilation standard from C++11 to C++17. I had removed the setting for C++11 last year as compilation by compiler default worked well enough. But the version at CRAN still carried, which started to lead to build failures on Debian unstable so it was time for an update. And rather than implicitly relying on C++17 as selected by the last two R releases, we made it explicit. Otherwise a few of the regular package and repository updates have been made, but no new code or features were added The NEWS entries follow.

Changes in version 0.0.10 (2024-11-29)
  • Package maintenance updating continuous integration script versions as well as coverage link from README, and switching to Authors@R
  • C++ compilation standards updated to C++17 to comply with libapt-pkg

Courtesy of my CRANberries, there is also a diffstat report for this release. A bit more information about the package is available here as well as at the GitHub repo. If you like this or other open-source work I do, you can now 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.

8 July 2024

Thorsten Alteholz: My Debian Activities in June 2024

FTP master This month I accepted 270 and rejected 23 packages. The overall number of packages that got accepted was 279.

Debian LTS This was my hundred-twentieth month that I did some work for the Debian LTS initiative, started by Raphael Hertzog at Freexian. During my allocated time I uploaded or worked on: This month handling of the CVE of cups was a bit messy. After lifting the embargo of the CVE, a published patch did not work with all possible combinations of the configuration. In other words, in cases of having only one local domain socket configured, the cupsd did not start and failed with a strange error. Anyway, upstream published a new set of patches, which made cups work again. Unfortunately this happended just before the latest point release for Bullseye and Bookworm, so that the new packages did not make it into the release, but stopped in the corresponding p-u-queues: stable-p-u and old-p-u. I also continued to work on tiff and last but not least did a week of FD and attended the monthly LTS/ELTS meeting. Debian ELTS This month was the seventy-first ELTS month. During my allocated time I tried to upload a new version of cups for Jessie and Stretch. Unfortunately this was stopped due to an autopkgtest error, which I could not reproduce yet. I also wanted to finally upload a fixed version of exim4. Unfortunately this was stopped due to lots of CI-jobs for Buster. Updates for Buster are now also availble from ELTS, so some stuff had to prepared before the actual switch end of June. Additionally everything was delayed due to a crash of the CI worker. All in all this month was rather ill-fated. At least the exim4 upload will happen/already happened in July. I also continued to work on an update for libvirt, did a week of FD and attended the LTS/ELTS meeting. Debian Printing This month I uploaded new upstream or bugfix versions of: This work is generously funded by Freexian! Debian Astro This month I uploaded a new upstream or bugfix version of: All of those uploads are somehow related to /usr-move. Debian IoT This month I uploaded new upstream or bugfix versions of: Debian Mobcom The following packages have been prepared by the GSoC student Nathan: misc This month I uploaded new upstream or bugfix versions of: Here as well all uploads are somehow related to /usr-move

11 January 2024

Reproducible Builds: Reproducible Builds in December 2023

Welcome to the December 2023 report from the Reproducible Builds project! In these reports we outline the most important things that we have been up to over the past month. As a rather rapid 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 (more).

Reproducible Builds: Increasing the Integrity of Software Supply Chains awarded IEEE Software Best Paper award In February 2022, we announced in these reports that a paper written by Chris Lamb and Stefano Zacchiroli was now available in the March/April 2022 issue of IEEE Software. Titled Reproducible Builds: Increasing the Integrity of Software Supply Chains (PDF). This month, however, IEEE Software announced that this paper has won their Best Paper award for 2022.

Reproducibility to affect package migration policy in Debian In a post summarising the activities of the Debian Release Team at a recent in-person Debian event in Cambridge, UK, Paul Gevers announced a change to the way packages are migrated into the staging area for the next stable Debian release based on its reproducibility status:
The folks from the Reproducibility Project have come a long way since they started working on it 10 years ago, and we believe it s time for the next step in Debian. Several weeks ago, we enabled a migration policy in our migration software that checks for regression in reproducibility. At this moment, that is presented as just for info, but we intend to change that to delays in the not so distant future. We eventually want all packages to be reproducible. To stimulate maintainers to make their packages reproducible now, we ll soon start to apply a bounty [speedup] for reproducible builds, like we ve done with passing autopkgtests for years. We ll reduce the bounty for successful autopkgtests at that moment in time.

Speranza: Usable, privacy-friendly software signing Kelsey Merrill, Karen Sollins, Santiago Torres-Arias and Zachary Newman have developed a new system called Speranza, which is aimed at reassuring software consumers that the product they are getting has not been tampered with and is coming directly from a source they trust. A write-up on TechXplore.com goes into some more details:
What we have done, explains Sollins, is to develop, prove correct, and demonstrate the viability of an approach that allows the [software] maintainers to remain anonymous. Preserving anonymity is obviously important, given that almost everyone software developers included value their confidentiality. This new approach, Sollins adds, simultaneously allows [software] users to have confidence that the maintainers are, in fact, legitimate maintainers and, furthermore, that the code being downloaded is, in fact, the correct code of that maintainer. [ ]
The corresponding paper is published on the arXiv preprint server in various formats, and the announcement has also been covered in MIT News.

Nondeterministic Git bundles Paul Baecher published an interesting blog post on Reproducible git bundles. For those who are not familiar with them, Git bundles are used for the offline transfer of Git objects without an active server sitting on the other side of a network connection. Anyway, Paul wrote about writing a backup system for his entire system, but:
I noticed that a small but fixed subset of [Git] repositories are getting backed up despite having no changes made. That is odd because I would think that repeated bundling of the same repository state should create the exact same bundle. However [it] turns out that for some, repositories bundling is nondeterministic.
Paul goes on to to describe his solution, which involves forcing git to be single threaded makes the output deterministic . The article was also discussed on Hacker News.

Output from libxlst now deterministic libxslt is the XSLT C library developed for the GNOME project, where XSLT itself is an XML language to define transformations for XML files. This month, it was revealed that the result of the generate-id() XSLT function is now deterministic across multiple transformations, fixing many issues with reproducible builds. As the Git commit by Nick Wellnhofer describes: 
Rework the generate-id() function to return deterministic values. We use
a simple incrementing counter and store ids in the 'psvi' member of
nodes which was freed up by previous commits. The presence of an id is
indicated by a new "source node" flag.
This fixes long-standing problems with reproducible builds, see
https://bugzilla.gnome.org/show_bug.cgi?id=751621
This also hardens security, as the old implementation leaked the
difference between a heap and a global pointer, see
https://bugs.chromium.org/p/chromium/issues/detail?id=1356211
The old implementation could also generate the same id for dynamically
created nodes which happened to reuse the same memory. Ids for namespace
nodes were completely broken. They now use the id of the parent element
together with the hex-encoded namespace prefix.

Community updates There were made a number of improvements to our website, including Chris Lamb fixing the generate-draft script to not blow up if the input files have been corrupted today or even in the past [ ], Holger Levsen updated the Hamburg 2023 summit to add a link to farewell post [ ] & to add a picture of a Post-It note. [ ], and Pol Dellaiera updated the paragraph about tar and the --clamp-mtime flag [ ]. On our mailing list this month, Bernhard M. Wiedemann posted an interesting summary on some of the reasons why packages are still not reproducible in 2023. diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb made a number of changes, including processing objdump symbol comment filter inputs as Python byte (and not str) instances [ ] and Vagrant Cascadian extended diffoscope support for GNU Guix [ ] and updated the version in that distribution to version 253 [ ].

Challenges of Producing Software Bill Of Materials for Java Musard Balliu, Benoit Baudry, Sofia Bobadilla, Mathias Ekstedt, Martin Monperrus, Javier Ron, Aman Sharma, Gabriel Skoglund, C sar Soto-Valero and Martin Wittlinger (!) of the KTH Royal Institute of Technology in Sweden, have published an article in which they:
deep-dive into 6 tools and the accuracy of the SBOMs they produce for complex open-source Java projects. Our novel insights reveal some hard challenges regarding the accurate production and usage of software bills of materials.
The paper is available on arXiv.

Debian Non-Maintainer campaign As mentioned in previous reports, the Reproducible Builds team within Debian has been organising a series of online and offline sprints in order to clear the huge backlog of reproducible builds patches submitted by performing so-called NMUs (Non-Maintainer Uploads). During December, Vagrant Cascadian performed a number of such uploads, including: In addition, Holger Levsen performed three no-source-change NMUs in order to address the last packages without .buildinfo files in Debian trixie, specifically lorene (0.0.0~cvs20161116+dfsg-1.1), maria (1.3.5-4.2) and ruby-rinku (1.7.3-2.1).

Reproducibility testing framework The Reproducible Builds project operates a comprehensive testing framework (available at tests.reproducible-builds.org) in order to check packages and other artifacts for reproducibility. In December, a number of changes were made by Holger Levsen:
  • Debian-related changes:
    • Fix matching packages for the [R programming language](https://en.wikipedia.org/wiki/R_(programming_language). [ ][ ][ ]
    • Add a Certbot configuration for the Nginx web server. [ ]
    • Enable debugging for the create-meta-pkgs tool. [ ][ ]
  • Arch Linux-related changes
    • The asp has been deprecated by pkgctl; thanks to dvzrv for the pointer. [ ]
    • Disable the Arch Linux builders for now. [ ]
    • Stop referring to the /trunk branch / subdirectory. [ ]
    • Use --protocol https when cloning repositories using the pkgctl tool. [ ]
  • Misc changes:
    • Install the python3-setuptools and swig packages, which are now needed to build OpenWrt. [ ]
    • Install pkg-config needed to build Coreboot artifacts. [ ]
    • Detect failures due to an issue where the fakeroot tool is implicitly required but not automatically installed. [ ]
    • Detect failures due to rename of the vmlinuz file. [ ]
    • Improve the grammar of an error message. [ ]
    • Document that freebsd-jenkins.debian.net has been updated to FreeBSD 14.0. [ ]
In addition, node maintenance was performed by Holger Levsen [ ] and Vagrant Cascadian [ ].

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:
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:

7 December 2023

Daniel Kahn Gillmor: New OpenPGP certificate for dkg, December 2023

dkg's New OpenPGP certificate in December 2023 In December of 2023, I'm moving to a new OpenPGP certificate. You might know my old OpenPGP certificate, which had an fingerprint of C29F8A0C01F35E34D816AA5CE092EB3A5CA10DBA. My new OpenPGP certificate has a fingerprint of: D477040C70C2156A5C298549BB7E9101495E6BF7. Both certificates have the same set of User IDs:
  • Daniel Kahn Gillmor
  • <dkg@debian.org>
  • <dkg@fifthhorseman.net>
You can find a version of this transition statement signed by both the old and new certificates at: https://dkg.fifthhorseman.net/2023-dkg-openpgp-transition.txt The new OpenPGP certificate is: 
-----BEGIN PGP PUBLIC KEY BLOCK-----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=9Yc8
-----END PGP PUBLIC KEY BLOCK-----
When I have some reasonable number of certifications, i'll update the certificate associated with my e-mail addresses on https://keys.openpgp.org, in DANE, and in WKD. Until then, those lookups should continue to provide the old certificate.

10 October 2023

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

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

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

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

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

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

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

12 September 2023

Jo Shields: Building a NAS

The status quo Back in 2015, I bought an off-the-shelf NAS, a QNAP TS-453mini, to act as my file store and Plex server. I had previously owned a Synology box, and whilst I liked the Synology OS and experience, the hardware was underwhelming. I loaded up the successor QNAP with four 5TB drives in RAID10, and moved all my files over (after some initial DoA drive issues were handled).
QNAP TS-453mini product photoQNAP TS-453mini product photo
That thing has been in service for about 8 years now, and it s been a mixed bag. It was definitely more powerful than the predecessor system, but it was clear that QNAP s OS was not up to the same standard as Synology s perhaps best exemplified by HappyGet 2 , the QNAP webapp for downloading videos from streaming services like YouTube, whose icon is a straight rip-off of StarCraft 2. On its own, meaningless but a bad omen for overall software quality
The logo for QNAP HappyGet 2 and Blizzard's Starcraft 2 side by sideThe logo for QNAP HappyGet 2 and Blizzard s StarCraft 2 side by side
Additionally, the embedded Celeron processor in the NAS turned out to be an issue for some cases. It turns out, when playing back videos with subtitles, most Plex clients do not support subtitles properly instead they rely on the Plex server doing JIT transcoding to bake the subtitles directly into the video stream. I discovered this with some Blu-Ray rips of Game of Thrones some episodes would play back fine on my smart TV, but episodes with subtitled Dothraki speech would play at only 2 or 3 frames per second. The final straw was a ransomware attack, which went through all my data and locked every file below a 60MiB threshold. Practically all my music gone. A substantial collection of downloaded files, all gone. Some of these files had been carried around since my college days digital rarities, or at least digital detritus I felt a real sense of loss at having to replace. This episode was caused by a ransomware targeting specific vulnerabilities in the QNAP OS, not an error on my part. So, I decided to start planning a replacement with:
  • A non-garbage OS, whilst still being a NAS-appliance type offering (not an off-the-shelf Linux server distro)
  • Full remote management capabilities
  • A small form factor comparable to off-the-shelf NAS
  • A powerful modern CPU capable of transcoding high resolution video
  • All flash storage, no spinning rust
At the time, no consumer NAS offered everything (The Asustor FS6712X exists now, but didn t when this project started), so I opted to go for a full DIY rather than an appliance not the first time I ve jumped between appliances and DIY for home storage.

Selecting the core of the system There aren t many companies which will sell you a small motherboard with IPMI. Supermicro is a bust, so is Tyan. But ASRock Rack, the server division of third-tier motherboard vendor ASRock, delivers. Most of their boards aren t actually compliant Mini-ITX size, they re a proprietary Deep Mini-ITX with the regular screw holes, but 40mm of extra length (and a commensurately small list of compatible cases). But, thankfully, they do have a tiny selection of boards without the extra size, and I stumbled onto the X570D4I-2T, a board with an AMD AM4 socket and the mature X570 chipset. This board can use any AMD Ryzen chip (before the latest-gen Ryzen 7000 series); has built in dual 10 gigabit ethernet; IPMI; four (laptop-sized) RAM slots with full ECC support; one M.2 slot for NVMe SSD storage; a PCIe 16x slot (generally for graphics cards, but we live in a world of possibilities); and up to 8 SATA drives OR a couple more NVMe SSDs. It s astonishingly well featured, just a shame it costs about $450 compared to a good consumer-grade Mini ITX AM4 board costing less than half that. I was so impressed with the offering, in fact, that I crowed about it on Mastodon and ended up securing ASRock another sale, with someone else looking into a very similar project to mine around the same timespan. The next question was the CPU. An important feature of a system expected to run 24/7 is low power, and AM4 chips can consume as much as 130W under load, out of the box. At the other end, some models can require as little as 35W under load the OEM-only GE suffix chips, which are readily found for import on eBay. In their PRO variant, they also support ECC (all non-G Ryzen chips support ECC, but only Pro G chips do). The top of the range 8 core Ryzen 7 PRO 5750GE is prohibitively expensive, but the slightly weaker 6 core Ryzen 5 PRO 5650GE was affordable, and one arrived quickly from Hong Kong. Supplemented with a couple of cheap 16 GiB SODIMM sticks of DDR4 PC-3200 direct from Micron for under $50 a piece, that left only cooling as an unsolved problem to get a bootable test system. The official support list for the X570D4I-2T only includes two rackmount coolers, both expensive and hard to source. The reason for such a small list is the non standard cooling layout of the board instead of an AM4 hole pattern with the standard plastic AM4 retaining clips, it has an Intel 115x hole pattern with a non-standard backplate (Intel 115x boards have no backplate, the stock Intel 115x cooler attaches to the holes with push pins). As such every single cooler compatibility list excludes this motherboard. However, the backplate is only secured with a mild glue with minimal pressure and a plastic prying tool it can be removed, giving compatibility with any 115x cooler (which is basically any CPU cooler for more than a decade). I picked an oversized low profile Thermalright AXP120-X67 hoping that its 120mm fan would cool the nearby MOSFETs and X570 chipset too.
Thermalright AXP120-X67, AMD Ryzen 5 PRO 5650GE, ASRock Rack X570D4I-2T, all assembled and running on a flat surface

Testing up to this point Using a spare ATX power supply, I had enough of a system built to explore the IPMI and UEFI instances, and run MemTest86 to validate my progress. The memory test ran without a hitch and confirmed the ECC was working, although it also showed that the memory was only running at 2933 MT/s instead of the rated 3200 MT/s (a limit imposed by the motherboard, as higher speeds are considered overclocking). The IPMI interface isn t the best I ve ever used by a long shot, but it s minimum viable and allowed me to configure the basics and boot from media entirely via a Web browser.
Memtest86 showing test progress, taken from IPMI remote control window
One sad discovery, however, which I ve never seen documented before, on PCIe bifurcation. With PCI Express, you have a number of lanes which are allocated in groups by the motherboard and CPU manufacturer. For Ryzen prior to Ryzen 7000, that s 16 lanes in one slot for the graphics card; 4 lanes in one M.2 connector for an SSD; then 4 lanes connecting the CPU to the chipset, which can offer whatever it likes for peripherals or extra lanes (bottlenecked by that shared 4x link to the CPU, if it comes down to it). It s possible, with motherboard and CPU support, to split PCIe groups up for example an 8x slot could be split into two 4x slots (eg allowing two NVMe drives in an adapter card NVME drives these days all use 4x). However with a Cezanne Ryzen with integrated graphics, the 16x graphics card slot cannot be split into four 4x slots (ie used for for NVMe drives) the most bifurcation it allows is 8x4x4x, which is useless in a NAS.
Screenshot of PCIe 16x slot bifurcation options in UEFI settings, taken from IPMI remote control window
As such, I had to abandon any ideas of an all-NVMe NAS I was considering: the 16x slot split into four 4x, combined with two 4x connectors fed by the X570 chipset, to a total of 6 NVMe drives. 7.6TB U.2 enterprise disks are remarkably affordable (cheaper than consumer SATA 8TB drives), but alas, I was locked out by my 5650GE. Thankfully I found out before spending hundreds on a U.2 hot swap bay. The NVMe setup would be nearly 10x as fast as SATA SSDs, but at least the SATA SSD route would still outperform any spinning rust choice on the market (including the fastest 10K RPM SAS drives)

Containing the core The next step was to pick a case and power supply. A lot of NAS cases require an SFX (rather than ATX) size supply, so I ordered a modular SX500 unit from Silverstone. Even if I ended up with a case requiring ATX, it s easy to turn an SFX power supply into ATX, and the worst result is you have less space taken up in your case, hardly the worst problem to have. That said, on to picking a case. There s only one brand with any cachet making ITX NAS cases, Silverstone. They have three choices in an appropriate size: CS01-HS, CS280, and DS380. The problem is, these cases are all badly designed garbage. Take the CS280 as an example, the case with the most space for a CPU cooler. Here s how close together the hotswap bay (right) and power supply (left) are:
Internal image of Silverstone CS280 NAS build. Image stolen from ServeTheHome
With actual cables connected, the cable clearance problem is even worse:
Internal image of Silverstone CS280 NAS build. Image stolen from ServeTheHome
Remember, this is the best of the three cases for internal layout, the one with the least restriction on CPU cooler height. And it s garbage! Total hot garbage! I decided therefore to completely skip the NAS case market, and instead purchase a 5.25 -to-2.5 hot swap bay adapter from Icy Dock, and put it in an ITX gamer case with a 5.25 bay. This is no longer a served market 5.25 bays are extinct since nobody uses CD/DVD drives anymore. The ones on the market are really new old stock from 2014-2017: The Fractal Design Core 500, Cooler Master Elite 130, and Silverstone SUGO 14. Of the three, the Fractal is the best rated so I opted to get that one however it seems the global supply of new old stock fully dried up in the two weeks between me making a decision and placing an order leaving only the Silverstone case. Icy Dock have a selection of 8-bay 2.5 SATA 5.25 hot swap chassis choices in their ToughArmor MB998 series. I opted for the ToughArmor MB998IP-B, to reduce cable clutter it requires only two SFF-8611-to-SF-8643 cables from the motherboard to serve all eight bays, which should make airflow less of a mess. The X570D4I-2T doesn t have any SATA ports on board, instead it has two SFF-8611 OCuLink ports, each supporting 4 PCI Express lanes OR 4 SATA connectors via a breakout cable. I had hoped to get the ToughArmor MB118VP-B and run six U.2 drives, but as I said, the PCIe bifurcation issue with Ryzen G chips meant I wouldn t be able to run all six bays successfully.
NAS build in Silverstone SUGO 14, mid build, panels removed
Silverstone SUGO 14 from the front, with hot swap bay installed

Actual storage for the storage server My concept for the system always involved a fast boot/cache drive in the motherboard s M.2 slot, non-redundant (just backups of the config if the worst were to happen) and separate storage drives somewhere between 3.8 and 8 TB each (somewhere from $200-$350). As a boot drive, I selected the Intel Optane SSD P1600X 58G, available for under $35 and rated for 228 years between failures (or 11,000 complete drive rewrite cycles). So, on to the big expensive choice: storage drives. I narrowed it down to two contenders: new-old-stock Intel D3-S4510 3.84TB enterprise drives, at about $200, or Samsung 870 QVO 8TB consumer drives, at about $375. I did spend a long time agonizing over the specification differences, the ZFS usage reports, the expected lifetime endurance figures, but in reality, it came down to price $1600 of expensive drives vs $3200 of even more expensive drives. That s 27TB of usable capacity in RAID-Z1, or 23TB in RAID-Z2. For comparison, I m using about 5TB of the old NAS, so that s a LOT of overhead for expansion.
Storage SSD loaded into hot swap sled

Booting up Bringing it all together is the OS. I wanted an appliance NAS OS rather than self-administering a Linux distribution, and after looking into the surrounding ecosystems, decided on TrueNAS Scale (the beta of the 2023 release, based on Debian 12).
TrueNAS Dashboard screenshot in browser window
I set up RAID-Z1, and with zero tuning (other than enabling auto-TRIM), got the following performance numbers:
IOPSBandwidth
4k random writes19.3k75.6 MiB/s
4k random reads36.1k141 MiB/s
Sequential writes 2300 MiB/s
Sequential reads 3800 MiB/s
Results using fio parameters suggested by Huawei
And for comparison, the maximum theoretical numbers quoted by Intel for a single drive:
IOPSBandwidth
4k random writes16k?
4k random reads90k?
Sequential writes 280 MiB/s
Sequential reads 560 MiB/s
Numbers quoted by Intel SSD successors Solidigm.
Finally, the numbers reported on the old NAS with four 7200 RPM hard disks in RAID 10:
IOPSBandwidth
4k random writes4301.7 MiB/s
4k random reads800632 MiB/s
Sequential writes 311 MiB/s
Sequential reads 566 MiB/s
Performance seems pretty OK. There s always going to be an overhead to RAID. I ll settle for the 45x improvement on random writes vs. its predecessor, and 4.5x improvement on random reads. The sequential write numbers are gonna be impacted by the size of the ZFS cache (50% of RAM, so 16 GiB), but the rest should be a reasonable indication of true performance. It took me a little while to fully understand the TrueNAS permissions model, but I finally got Plex configured to access data from the same place as my SMB shares, which have anonymous read-only access or authenticated write access for myself and my wife, working fine via both Linux and Windows. And that s it! I built a NAS. I intend to add some fans and more RAM, but that s the build. Total spent: about $3000, which sounds like an unreasonable amount, but it s actually less than a comparable Synology DiskStation DS1823xs+ which has 4 cores instead of 6, first-generation AMD Zen instead of Zen 3, 8 GiB RAM instead of 32 GiB, no hardware-accelerated video transcoding, etc. And it would have been a whole lot less fun!
The final system, powered up
(Also posted on PCPartPicker)

Next.