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Joined 1 year ago
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Cake day: June 6th, 2023

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  • As far as I understand, in this case opaque binary test data was gradually added to the repository. Also the built binaries did not correspond 1:1 with the code in the repo due to some buildchain reasons. Stuff like this makes it difficult to spot deliberately placed bugs or backdors.

    I think some measures can be:

    • establish reproducible builds in CI/CD pipelines
    • ban opaque data from the repository. I read some people expressing justification for this test-data being opaque, but that is nonsense. There’s no reason why you couldn’t compress+decompress a lengthy creative commons text, or for binary data encrypt that text with a public password, or use a sequence from a pseudo random number generator with a known seed, or a past compiled binary of this very software, or … or … or …
    • establish technologies that make it hard to place integer overflows or deliberately miss array ends. That would make it a lot harder to plant a misbehavement in the code without it being so obvious that others note easily. Rust, Linters, Valgrind etc. would be useful things for that.

    So I think from a technical perspective there are ways to at least give attackers a hard time when trying to place covert backdoors. The larger problem is likely who does the work, because scalability is just such a hard problem with open source. Ultimately I think we need to come together globally and bear this work with many shoulders. For example the “prossimo” project by the Internet Security Research Group (the organisation behind Let’s Encrypt) is working on bringing memory safety to critical projects: https://www.memorysafety.org/ I also sincerely hope the german Sovereign Tech Fund ( https://www.sovereigntechfund.de/ ) takes this incident as a new angle to the outstanding work they’re doing. And ultimately, we need many more such organisations and initiatives from both private companies as well as the public sector to protect the technology that runs our societies together.


  • Well you must have either set up a port redirect (ipv4) or opened the port for external traffic (ipv6) yourself. It is not reachable by default as home routers put a NAT between the internet and your devices, or in the case of ipv6 they block any requests. So (unless you have a very exotic and unsafe router) just uhhh don’t 😅 To serve websites it is enough to open 443 for https, and possibly 80 for http if you want to serve an automatic redirect to https.


  • That’s odd, I upgraded my ender 3 with bed leveling and removed the knobs to mount it fixed, because the damn knobs keep moving and then you have to redo the bed calibration. To be honest I can imagine one reason might be that a loosely mounted bed gives you more fault tolerance against the nozzle being too low. I put my bed on two parallel linear rollers for more rigidity, and combined with dual z screws the nozzle has no chance anymore to produce any sort of first layer when it is slightly too low. That made me realize just how much the stock ender 3 is flopping around, but also how this can give you mostly okayish results most of the time without having to deal with a ton of small tolerances.


  • A colleague of mine had a (non externally reachable) raspberry pi with default credentials being hijacked for a botnet by a infected windows computer in the home network. I guess you’ll always have people come over with their devices you do not know the security condition of. So I’ve started to consider the home network insecure too, and one of the things I want to set up is an internal ssh honeypot with notifications, so that I get informed about devices trying to hijack others. So for this purpose that tool seems a possibilty, hopefully it is possible to set up some monitoring and notification via uptime kuma.







  • True words. The sustained effort to keep something in decent shape over years is not to be underestimated. Now when life changes and one is not able or willing anymore to invest that amount of time, ill-timed issues can become quite the burden. At one point I decided to cut down on that by doing a better founded setup, that does backup with easy rollback automatically, and updates semi-automatically. I rely on my server(s), and all from having this idea to having it decently implemented took me a number of months. Just because time for such activities is limited, and getting a complex and intertwined system like this reliably and fault tolerant automated and monitored is simply something else than spinning up a one off service


  • And they believe all employees actually remember so many wildly different and long passwords, and change them regularly to wildly different ones? All this leads to is a single password that barely makes it over the minimum requirements, and a suffix for the stage (like 1 for boot, 2 for bitlocker etc), and then another suffix for the month they changed it. All of that then on sticky notes on the screen.





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    9 months ago

    Those are symptoms of sitting at that operation point permanently, and they are a of course a concern. What I’m after is that people think that energy gets put in to the battery, i.e. it gets charged, as long as a “charger” is connected to the device (hence terms like “overcharged”). But that is not true, because what is commonly referred to as “charger” is no charger. It is just a power supply and has literally zero say in if, how and when the battery gets charged. It only gets charged if the charge controller in the device decides to do that now, and if the protection circuit allows it. And that is designed to only happen if the battery is not full. When it is full, nothing more happens, no currents flow in+out of the battery anymore. There’s no damage due to being charged all the time, because no device keeps on pumping energy into the cell if it is full.

    There is however damage from sitting (!) at 100% charge with medium to high heat. That happens indipendently from a power supply being connected to the device or not. You can just as well damage your cells by charging them to 100% and storing them in a warm place while topping them of once in a while. This is why you want to have them at lower room temperature and at ~60%, no matter if a device/“charger” is connected or not.

    (Of course keeping a battery at 60% all the time defeats the purpose of the battery. So just try to keep it cool, charged to >20% and <80% most of the time, and you’re fine)


  • “overcharging” doesn’t exist. There are two circuits preventing the battery from being charged beyond 100%: the usual battery controller, and normally another protection circuit in the battery cell. Sitting at 100% and being warm all the time is enough for a significant hit on the cell’s longetivity though. An easy measure that is possible on many laptops (like thinkpads) is to set a threshold where to stop charging at. Ideal for longetivity is around 60%. Also ensure good cooling.

    Sorry for being pedantic, but as an electricial engineer it annoys me that there’s more wrong information about li-po/-ion batteries, chargers and even usb wall warts and usb power delivery than there’s correct information.


  • It is not that easy to understand what you want, to me it reads like you want something like Nextcloud - i.e. your own little cloud, where you can put all your stuff, and view it through the webbrowser or the nextcloud apps, and also keep selected parts of your stuff in sync with your devices (or automatically upload photos take with your smartphone for example).

    Backup of Nextcloud (or whatever you want to use) is a seperate topic. Any incremental backup tool would apply though, so there’s much to choose from. I personally use btrbk which uses Btrfs Send+Receive to push incremental snapshots to an offsite server.