You can bet your last dollar that if the "right" RedHat or Debian developer rewrote sudo with feature parity, it would be adopted by all major distros in a couple of months. It's the sort of thing nobody really cares about except OpenBSD (which wrote their own).
The problem is feature parity. Most rewrites cannot guarantee that off-the-bat, so they end up struggling to persuade people to switch - why break stuff that works just fine and lose features, in the name of some engineering purity?
It's using D-bus. My faith in D-bus security is close to my faith in seeing a fresh Linux install with zero D-bus error messages from apps. Which is to say, nonexistent.
> integrates with your DE instead of expecting passwords on the terminal.
There's nothing inherently insecure about passwords on the terminal, and certainly nothing a DE can do better. I have yet to see a display manager or lock screen app that knows what the hell PAM is doing. Try doing even the simplest things with PAM, such as getting a fingerprint reader or Yubikey working, and every single display manager simply chokes.
I'm not sure which is more of a Byzantine mess: Linux authentication and authorization, or Linux audio.
With all the .so modules loading into some process, etc. Some questionable design in sshd makes it lock up completely for all incoming connections when used with PAM and when pam module ends up in infinite loop.
Nevermind that systemd pam modules pull in a shitton of stuff, including dbus, into any process that tries to use PAM for auth, these days.
I guess it all runs as root, too. sshd at least tries to fork a child for all this and waits for it and kills it, so that the parent process can't be polluted. It just has no timeout when waiting for result, and doesn't accept further connections when waiting.
Sometimes it's better not to look too deep under the covers.
How else would you implement PAM? The whole point is that you can write arbitrary code to implement whatever custom authentication policy you have, so it needs to be able to dlopen things. And if you don't like the PAM policy written by your distro, you're free to change it by implementing your own authentication policies, or dropping things you don't care about (like systemd, you can configure PAM to just use /etc/passwd and /etc/shadow if you like).
sshd needs to run as root (obviously) because it grants login shells to people, so it needs to run in a privileged context. And the PAM modules it executes also need to be run as root, because PAM modules need to do things like read /etc/shadow.
That's part of the dark outcome of so many untested features: it makes it easy to cast FUD upon any potential replacements. As we have no black-box test suite that shows `sudo` implements all of these features, so we also cannot have faith that any replacement would. Ideally it should be possible to run sudo's black box tests against any potential replacement. To start with, we need those tests.
The problem is feature parity. Most rewrites cannot guarantee that off-the-bat, so they end up struggling to persuade people to switch - why break stuff that works just fine and lose features, in the name of some engineering purity?