Hi, I was asked to give an overview of what Wayland-related stuff is on the radar for the near future, so here we go: crosvm security contexts ------------------------ The Wayland security context protocol[1] is how the compositor will know which VM is responsible for which Wayland client, which will allow us to make per-VM policy decisions. crosvm is the part of Spectrum's stack that can give this information to the compositor, so we need it to implement this protocol. Puck previously created such an implementation[2], but it was for an earlier draft of the protocol. It needs to be updated and submitted upstream. [1]: https://wayland.app/protocols/security-context-v1 [2]: https://puck.moe/git/crosvm/commit/?h=wayland-security-context&id=dbdba0bf64... Customisable COSMIC ------------------- I plan to use the COSMIC[3] the compositor for Spectrum. As far as I know, it's the only serious Rust Wayland compositor, and it looks like it's targeting a good balance between wide usability and configurability. But Spectrum's compositor has some requirements that wouldn't make sense for upstream COSMIC. For example, we'll want to implement some sort of clipboard permissions system, and we're likely to want to do some sort of custom window decorations, maybe like Qubes does. Maintaining a fork of cosmic-comp wouldn't be sustainable, so what we need is some way to customize the compositor's behaviour without needing out-of-tree patches. The way I imagine this working is having cosmic-comp export a library that allows inserting hooks for things we might want to customise. Then we could write a very small program that used that library, set up whatever hooks we wanted, and then just told the library to run the compositor. Quick sketch: use cosmic_comp::{Hook, add_hook, run}; fn main() { add_hook(Hook::Paste, |ctx| { ... }); run(); } I've talked to upstream about this, and they're on board with the general concept. Doing it this way would mean the only code we'd have to maintain would be Spectrum-specific, and we wouldn't have to worry about running into merge conflicts forever. Once this is done, we can do things like implement security contexts in cosmic-comp. It wouldn't make much sense to do that first, because it wouldn't be used anywhere. [3]: https://github.com/pop-os/cosmic-epoch#cosmic-comp COSMIC title bars for wayland-proxy-virtwl Xwayland clients ----------------------------------------------------------- wayland-proxy-virtwl[4] is the program used to relay Wayland connections from the guest to the host. It implements its own unpriveleged X11 forwarding. (Normal Xwayland requires the compositor give special priveleges not given to normal Wayland clients.) For some reason, cosmic-comp does not draw title bars for these clients. It's unclear so far whether this is a cosmic-comp program or a wayland-proxy-virtwl problem. [4]: https://github.com/talex5/wayland-proxy-virtwl