A GTK4 SSH-askpass in Zig

(xn--gckvb8fzb.com)

67 points | by surprisetalk a day ago ago

27 comments

  • danudey a day ago

    Noticed that when I build this it ends up with direct linking against a half-dozen libraries it doesn't actually use, at least on Ubuntu. Fixed it by replacing the linking commands with this:

        exe_mod.linkSystemLibrary("gtk-4", .{ .use_pkg_config = .no });
        exe_mod.linkSystemLibrary("gobject-2.0", .{});
    
    In my case, at least, this doesn't change the full library tree because gtk-4 still links against all of the libraries that are removed from this binary's list, but it does mean that programs which calculate dependencies, like dpkg-shlibdeps, won't report spurious "required" dependencies when analyzing the binary.

    When building on Ubuntu 26.04, the binary no longer directly links against lib{pango, cairo, pangocairo, cairo-gobject, harfbuzz, gdk_pixbuf, graphene, gio, vulkan}.

    Can't create an account on the site so I figured I'd post this here. If you're going for absolute minimalism this seems like another step in the right direction for anyone building on a more 'gratuitous' GTK build (such as Ubuntu's)

  • DannyBee a day ago

    Whenever someone writes "with hand-written bindings" I read "will stop working 8 minutes after the next release"

    • pseudony a day ago

      There are tools to generate bindings. They probably meant it as a marker of quality.

      And in languages like zig or odin which are quite similar to C in many ways, writing bindings to C code really isn’t bad. It is so easy that I decided to write my own bindings in Odin to sqlite - bindings exist but it really was so very easy that I didn’t want to bring in a generator or another dependency.

  • gen2brain a day ago

    Nice, I just use lxqt-openssh-askpass, but I am on X11. A lighter alternative (for single-text input) would be FLTK. Version 1.4 is really nice, with Wayland support, and they even draw custom window decorations on GNOME. Both Cairo and FLTK should be able to compile with -X; not sure, though, about the status of the Zig bindings.

    • zem a day ago

      fltk is c++ based which makes language bindings significantly harder in general. gtk is c based which worked out really well in that aspect.

      • gen2brain a day ago

        Sure, you need to wrap it in C, but there is also `cfltk` that is maintained and used in Rust bindings. Btw., the difference in memory usage is huge with GTK4. FLTK hello world is ~10M, GTK3 is ~15M, GTK4 is 40M! With Cairo rendering, it's about 30M, but still a lot.

        • Levitating a day ago

          GTK4 memory usage is ludicrous

        • zem a day ago

          ah neat, I wasn't aware that cfltk was already used by rust.

      • fithisux 11 hours ago

        There is cflt and Freebasic FLTK

  • porridgeraisin a day ago

    I wrap `pinentry` (which is in the dependency trees of gnupg, pacman, gvfs, udisks2 and other software that you can de-facto depend on on desktops) inside my own simple askpass.

      $ cat ~/scripts/pinentry-askpass
      #!/usr/bin/env bash
      
      pinentry <<INPUT | grep '^D ' | cut -c 3-
      SETPROMPT Password:
      GETPIN
      INPUT
    
      $ cat ~/.bashrc | grep ASKPASS
      export SUDO_ASKPASS="$HOME/scripts/pinentry-askpass"
      export SSH_ASKPASS="$SUDO_ASKPASS"
    
    It automatically launches the GTK, TTY, or QT version depending on your environment.

    It's also useful for agents to use sudo, you can write in instructions to tool-call `sudo -A` and you get a GUI popup to enter the password, and the agent continues from there. And since the "prompt" in pinentry can be customised... you can get the agent to set up a temporary askpass, which replaces "Password:" in the prompt with questions like "Can I delete this old log file in /var?" and you enter your password to authorise.

    • aorth 6 hours ago

      Any reason you don't use `pinentry-gnome3` from the `pinentry` package? Your wrapper is clever but doesn't work with gpg-agent.

      • porridgeraisin 5 hours ago

        No reason, I always thought launching pinentry directly chose the right one out of pinentry, pinentry-curses, pinentry-emacs, pinentry-gnome3, pinentry-gtk, pinentry-qt, pinentry-tty since it always worked for me on xfce+arch+programs I have used.

        You can change it I suppose, I don't thing I use gpg-agent often.

  • hparadiz a day ago

    These implementations really need to also include fingerprint sensor support

    • quotemstr a day ago

      PAM really needs to be ravamped and support for (among other things) running multiple stacks in par@llel added. This way you could ask for a password OR a fingerprint

      • timhh a day ago

        I'm vaguely considering rewriting PAM in Rust. It's definitely something that would benefit from Rust's extra security and the code quality isn't that great. Nor is the UX. What "among other things" were you thinking of?

        • quotemstr 18 hours ago

          Implementation language is incidental. Rust is... fine, I guess? But I wouldn't mandate modules use it. What's important is to move PAM out of process and sandbox the process host (using landlock, namespaces like bwrap, whatever) so we can run sensitive code with least-privilege on both ends.

          • timhh 13 hours ago

            Yeah I always thought the whole architecture of PAM being a library is weird. A sane person would have made it a Daemon that processes talk to surely?

            Really it should probably be part of SystemD, but I know that would anger the anti-SystemD zealots.

            • NekkoDroid 10 hours ago

              > A sane person would have made it a Daemon that processes talk to surely?

              > Really it should probably be part of SystemD

              https://github.com/systemd/systemd/pull/39855

              • quotemstr 3 hours ago

                It's confusing how they want a custom protocol that seems to be converging from JSON-RPC, just spelled differently. They should just use JSON-RPC. In any case, it'd essential to retain PAM's customization ability even if the bulk of the work is moved out-of-process.

            • quotemstr 3 hours ago

              Not everything has to be a "daemon". It's a bad trend in current programming zeitgeist to want to make everything into one. (sccache, no, you do NOT need a daemon to behave like ccache.)

              For a PAM replacement, you want a separate process. It doesn't have to be a persistent separate process.

      • hparadiz a day ago

        Keypassxc does it perfectly.

        • quotemstr a day ago

          Everyone doing parallel biometric and password authentication on Linux today is either running two PAM stacks in parallel (which is meta-policy that kind of defeats the purpose of PAM) or just bypassing PAM entirely.

    • xnickb a day ago

      Fingerprint is an authentication mechanism, not an authorization one.

  • bflesch a day ago

    Love the tab title shenanigans when switching to and from the tab.

  • WD-42 a day ago

    Would love to see more projects using gtk and zig. Always nice to have another language option.

  • hackingboy298 a day ago

    this is realy good and helpfull information thanks.