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CUPS | systemd | |
---|---|---|
52 | 510 | |
1,829 | 12,398 | |
0.8% | 1.5% | |
2.3 | 10.0 | |
5 months ago | 7 days ago | |
C | C | |
Apache License 2.0 | GNU General Public License v3.0 only |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
CUPS
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A new, modern, and secure print experience from Windows
If your printer for example supports IPP and Postscript or PDF then that would be possible. Higher end (commercial) HP printers usually offer this functionality. Take a look at CUPS [1] if you want to know more about IPP.
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Trying to set up an old Zebra LP2844 as a network printer
Your best bet is to set up a print server. The support page even has a CUPS driver. CUPS is well known for supporting a lot of printers. I run it on an old Mac-mini running Ubuntu. You can run it on something as small as a Raspberry Pi.
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PostScript’s Sudden Death in Sonoma
Apple should be more open about their removals. It isn't clear how this affects their CUPS implementation or PostScript printers https://www.cups.org
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Microsoft to kill off third-party printer drivers in Windows
CUPS is under the Apache License 2.0 , so they can just use it, if they wanted: https://github.com/apple/cups/blob/master/LICENSE
They won't of course.
- On the harm shareholders can do to OpenSource
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My collection of Ansible roles for self-hosting everything with Rocky Linux and FreeIPA
CUPS printing server
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Is this easily solvable? I am going crazy
Another alternative is for you to set up a print server in VLAN20. Then set up the print server to print to the printer in VLAN99. CUPS is pretty easy to set up.
- “Sorry to bother you” me, to my printer
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Sharing a Printer in a WiFi Network
But after both Apple and Linux switched their CUPS-based printing systems to Python 3 or some other breaking change that I don't mind to understand, the only way to print a document seemed to be using a PC running Microsoft Windows. So I had to save a PDF in the cloud or email it to myself, then startup Windows on a laptop physically connected to the printer, start the printing process, check if the paper has been printed successfully, and shut down Windows. What a waste of time and energy!
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House upgrade: Need to keep an old USB-only printer connected wirelessly, would this work? (Old Router connected to new router)
Another option is to set up a print server. There are free print server programs that you can run on a computer. CUPS is pretty popular. I used to run it on a Raspberry Pi for an ancient LaserJet 1012. That printer just keeps going.
systemd
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Linux fu: getting started with systemd
https://github.com/systemd/systemd/issues/32028#issuecomment...
There are some very compelling arguments made there if you care to read them
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Ubuntu 24.04 (and Debian) removed libsystemd from SSH server dependencies
Maybe it was because you weren't pointing out anything new?
There was a pull request to stop linking libzma to systemd before the attack even took place
https://github.com/systemd/systemd/pull/31550
This was likely one of many things that pushed the attackers to work faster, and forced them into making mistakes.
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Systemd minimizing required dependencies for libsystemd
The PR for changing compression libraries to use dlopen() was opened several weeks before the xz-utils backdoor was revealed.
- Going in circles without a real-time clock
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The xz sshd backdoor rabbithole goes quite a bit deeper
I find this the most plausible explanation by far:
* The highly professional outfit simply did not see teknoraver's commit to remove liblzma as standard dependency of systemd build scripts coming.
* The race was on between their compromised code and that commit. They had to win it, with as large a window as possible.
* This caused serious errors.
* The performance regression is __not__ big. It's lucky Andres caught it at all. It's also not necessarily all that simple to remove it. It's not simply a bug in a loop or some such.
* The payload of the 'hack' contains fairly easy ways for the xz hackers to update the payload. They actually used it to remove a real issue where their hackery causes issues with valgrind that might lead to discovering it, and they also used it to release 5.6.1 which rewrites significant chunks; I've as yet not read, nor know of any analysis, as to why they changed so much.
Extra info for those who don't know:
https://github.com/systemd/systemd/commit/3fc72d54132151c131...
That's a commit that changes how liblzma is a dependency of systemd. Not because the author of this commit knew anything was wrong with it. But, pretty much entirely by accident (although removing deps was part of the point of that commit), almost entirely eliminates the value of all those 2 years of hard work.
And that was with the finish line in sight for the xz hackers: On 24 feb 2024, the xz hackers release liblzma 5.6.0 which is the first fully operational compromised version. __12 days later systemd merges a commit that means it won't work__.
So now the race is on. Can they get 5.6.0 integrated into stable releases of major OSes _before_ teknoraver's commit that removes liblzma's status as direct dep of systemd?
I find it plausible that they knew about teknoraver's commit _just before_ Feb 24th 2024 (when liblzma v5.6.0 was released, the first backdoored release), and rushed to release ASAP, before doing the testing you describe. Buoyed by their efforts to add ways to update the payload which they indeed used - March 8th (after teknoraver's commit was accepted) it was used to fix the valgrind issue.
So, no, I don't find this weird, and I don't think the amateurish aspects should be taken as some sort of indication that parts of the outfit were amateuristic. As long as it's plausible that the amateuristic aspects were simply due to time pressure, it sounds like a really bad idea to make assumptions in this regard.
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Excellent succinct breakdown of the xz mess, from an OpenBSD developer
sshd is started by systemd.
systemd has several ways of starting programs and waiting until they're "ready" before starting other programs that depend on them: Type=oneshot, simple, exec, forking, dbus, notify, ...
A while back, several distro maintainers found problems with using Type=exec (?) and chose Type=notify instead. When sshd is ready, it notifies systemd. How you do notification is you send a datagram to systemd's unix domain socket. That's about 10 lines of C code. But to make life even simpler, systemd also provides the one-line sd_notify() call, which is in libsystemd.so. This library is so other programmers can easily integrate with systemd.
So the distro maintainers patched sshd to use the sd_notify() function from libsystemd.so
What else is in libsystemd.so? That's right, systemd also does logging. All the logging functions are in there, so user programs can do logging the systemd way. You can even _read_ logs, using the functions in libsystemd.so. For example, sd_journal_open_files().
By the way... systemd supports the environment variable SYSTEMD_JOURNAL_COMPRESS which can be LZ4, XZ or ZSTD, to allow systemd log files to be compressed.
So, if you're a client program, that needs to read systemd logs, you'll call sd_journal_open_files() in libsystemd.so, which may then need liblz4, liblzma or libzstd functions.
These compression libraries could be dynamically loaded, should sd_journal_open_files() need them - which is what https://github.com/systemd/systemd/pull/31550 submitted on the 29th February this year did. But clearly that's not in common use. No, right now, most libsystemd.so libraries have headers saying "you'll need to load liblz4.so, liblzma.so and libzstd before you can load me!", so liblzma.so gets loaded for the logging functions that sshd doesn't use, so the distro maintainers of sshd can add 1 line instead of 10 to notify systemd that sshd is ready.
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Reflections on Distrusting xz
They just added an example to the documentation[0] of how to implement the sd_notify protocol without linking to libsystemd, so a little bit of discarding systemd (or at least parts of it) does seem to be part of the solution.
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Timeline of the xz open source attack
I think this analysis is more interesting if you consider these two events in particular:
2024-02-29: On GitHub, @teknoraver sends pull request to stop linking liblzma into libsystemd.[1]
2024-03-20: The attacker is now a co-contributor for a patchset proposed to the Linux kernel, with the patchset adding the attacker as a maintainer and mirroring activity with xz-utils.
A theory is that the attacker saw the sshd/libsystemd/xz-utils vector as closing soon with libsystemd removing its dependency on xz-utils. When building a Linux kernel image, the resulting image is compressed by default with gzip [3], but can also be optionally compressed using xz-utils (amongst other compression utilities). There's a lot of distributions of Linux which have chosen xz-utils as the method used to compress kernel images, particularly embedded Linux distributions.[4] xz-utils is even the recommended mode of compression if a small kernel build image is desired.[5] If the attacker can execute code during the process of building a new kernel image, they can cause even more catastrophic impacts than targeting sshd. Targeting sshd was always going to be limited due to targets not exposing sshd over accessible networks, or implementing passive optical taps and real time behavioural analysis, or receiving real time alerts from servers indicative of unusual activity or data transfers. Targeting the Linux kernel would have far worse consequences possible, particularly if the attacker was targeting embedded systems (such as military transport vehicles [6]) where the chance of detection is reduced due to lack of eyeballs looking over it.
[1] https://github.com/systemd/systemd/pull/31550
[2] https://lkml.org/lkml/2024/3/20/1004
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...
[4] https://github.com/search?q=CONFIG_KERNEL_XZ%3Dy&type=code
[5] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...
[6] https://linuxdevices.org/large-military-truck-runs-embedded-...
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What we know about the xz Utils backdoor that almost infected the world
systemd merged a change to using dlopen for compression libraries recently https://github.com/systemd/systemd/pull/31550 which is a safer linking method in that sense.
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XZ: A Microcosm of the interactions in Open Source projects
1) Debian includes this downstream patch, also.
2) A potential explanation for "why now" is that systemd DID prevent these dependencies from loading automatically in a patch one month ago, and the patches enabling the backdoor merged a few days later. It could be a total coincidence or it could be that the attacker was trying to catch the window before it was closed on them https://github.com/systemd/systemd/pull/31550#issuecomment-1...
What are some alternatives?
Nginx Proxy Manager - Docker container for managing Nginx proxy hosts with a simple, powerful interface
openrc - The OpenRC init system
Paperless - Scan, index, and archive all of your paper documents
tini - A tiny but valid `init` for containers
mayan-edms
inotify-tools - inotify-tools is a C library and a set of command-line programs providing a simple interface to inotify.
cups - OpenPrinting CUPS Sources
s6 - The s6 supervision suite.
EdPaper - Helps you organizing your paperwork
earlyoom - earlyoom - Early OOM Daemon for Linux
pfSense - Main repository for pfSense
supervisor - Supervisor process control system for Unix (supervisord)