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Joined 2 years ago
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Cake day: June 12th, 2023

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  • BitTorrent breaks your data in blocks, each block is hashed, their sizes are known. Assuming you got your .torrent file from a legitimate source, it’s practically impossible to receive something else, as long as your client does all the checks properly.

    In theory, it is possible to write malware that will collide hashes with some other content, but considering you are restricted to the size of the actual content, it’s extremely unlikely that out of all the millions of .torrents we created so far we can find even one for which it is possible.

    And even if you win this absolutely bizzare lottery, you’ll be competing with legitimate peers for serving the blocks. If at least one block that you care about is not served by you, the recepient will just get corrupted content that won’t be dangerous in any way. In other words, you need to have so much bandwidth, that you serve everything before anyone else can serve even one significant block. At which point you will probably have to spend a lot more money on that than you’ll ever get from whatever malware you are trying to serve.


  • .for_each(|((_, _, t), (_, _, b))| { ... }
    

    This is actually fairly similar to what C# has.

    This is a closure syntax:

    | arguments | { calls }
    

    In C#, the closest is lambda expressions, declared like this:

    ( arguments ) => { calls }
    

    Parentheses are tuple deconstructors. In C# you have exactly the same thing. Imagine you have a method that returns a two element tuple. If you do this:

    var (one, two) = MethodThatReturnsATuple();
    

    You’ll get your tuple broken down automatically and variables one and two declared for you.

    First of all, I’m using .zip() to pair the rows of the picture by two, that returns a tuple, so, I have to deconstruct that. That’s what the outer parentheses are for. The pixel enumeration stuff I’m using returns a tuple (u32, u32, &Rgba<u8>) first two values are x and y of the pixel, the third one is a reference to a structure with color data. I deconstruct those and just discard the position of the pixel, you do that with an underscore, same as C#.

    I’m not that far into learning myself, but I’m not a textbook learner at all. Poking around opensource projects and wrestling with the compiler prooved to educate me a lot more.



  • I gladly present you this jank.

    You might need these to compile:

    cargo add image
    cargo add clap --features derive
    

    And the jank itself:

    Some Rust code
    use std::path::PathBuf;
    
    use clap::Parser;
    use image::{ imageops::{self, FilterType}, ImageReader };
    
    #[derive(Parser)]
    struct Cli {
        path: PathBuf,
        #[arg(short = 'H', long, default_value_t = 30)]
        height: u32,
        #[arg(short, long, default_value_t = 0.4)]
        ratio: f32,
        #[arg(short, long, default_value_t, value_enum)]
        filter: Filter,
    }
    
    #[derive(clap::ValueEnum, Clone, Default)]
    enum Filter {
        Nearest,
        Triangle,
        Gaussian,
        CatmullRom,
        #[default]
        Lanczos3,
    }
    
    fn main() -> Result<(), Box<dyn std::error::Error>> {
        let args = Cli::parse();
        let filter = match args.filter {
            Filter::Nearest    => { FilterType::Nearest },
            Filter::Triangle   => { FilterType::Triangle },
            Filter::CatmullRom => { FilterType::CatmullRom },
            Filter::Gaussian   => { FilterType::Gaussian },
            Filter::Lanczos3   => { FilterType::Lanczos3 },
        };
        let img = ImageReader::open(args.path)?.decode()?;
        let original_ratio = img.width() as f32 / img.height() as f32;
        let width = ( args.height as f32 / args.ratio ) * original_ratio;
        let out = imageops::resize(&img, width as u32, args.height * 2, filter);
        let mut iter = out.enumerate_rows();
        while let Some((_, top)) = iter.next() {
            let (_, bottom) = iter.next().unwrap();
            top.zip(bottom)
                .for_each(|((_, _, t), (_, _, b))| {
                    print!("\x1B[38;2;{};{};{};48;2;{};{};{}m\u{2584}", b[0], b[1], b[2], t[0], t[1], t[2])
                });
            println!("\x1B[0m");
        }
        Ok(())
    }
    


  • Assuming you made a bit of a typo with your regexp, any of these should work as you want:

    grep -oE '/dev/loop[0-9]+'
    awk 'match($0, /\/dev\/loop[0-9]+/) { print substr($0, RSTART, RLENGTH) }'
    sed -r 's%.*(/dev/loop[0-9]+).*%\1%'
    

    AWK one is a bit cursed as you can see. Such ways of manipulating text is not exactly it’s strong suite.


  • How did we arrive at networking? I feel like we are on two completely different pages.

    I was talking about your regular end user machines, what we usually call “desktop computers”. They are connected to the internet, but I don’t have any way to remotely login into those. And I have a single person per computer. There is no need to disable root passwords on these, seeing that Larry executed a command as root won’t provide any insight, I know that Larry is the only person who uses the machine. And it can complicate things in a sense that if Larry fatfingers his password three times and gets locked out, I’ll have to get into his filesystem somehow and remove tallies manually instead of just logging in as root and doing faillock --reset.


  • So, we are clearly talking about different environments here. Of course I would not have a password for root in an enterprize setting where you have a lot of different people managing one machine. But for your regular desktop computer with one user, it just complicates things needlessly without providing any benefits.


  • Maybe I’m a bit ignorant, but would it make much of a difference? Whether I authenticate with my own account to get root permissions or directly with root, I still have a string of characters which I use to get root priveleges on my machine. For a single (physical) user machine, that allows me to use a separate password for root. Should be better than using the same one twice, right?





  • For the love of all that’s saint, can we please stop recommending Manjaro to people, especially newbies?

    It’s not really a preference thing, Manjaro team did plenty of questionable stuff with it, as in DDoSing AUR, mind you, twice, or letting their server certificates expire, also more than once.

    It also routinely shows more stability issues that led to the infamous “I swear to god, if it’s Manjaro again…” in AUR discussions. Apart from AUR problems, they also shipped alpha quality things to their users, like this and this.

    I’ve used Manjaro myself for around a month. If you are treating it as a regular Arch installation, you will break it.

    If you want something up to date, but more stable than Arch, just use Fedora. If you insist on it being Arch-based, use something like CachyOS. Or you can read the wiki and install Arch itself. Arch is a DIY distro, after all.








  • I wouldn’t recommend vanilla Arch only because of the installation process. CachyOS that simplifies it is an extremely good pick for a person who already knows what a computer is, but wants to try a proper OS.

    Arch mostly got it’s reputation in the early days. Today some things are a lot easier to do on Arch than on other distros, especially because AUR exists. Also, it built one of the best wikis over all that time.