BUS1 Didn't Land This Year, But It's Making Progress

[carewolf]

Can somebody explain the point of BUS1? Wasn't the reason for KDBUS to move DBUS to the kernel for speed/security reasons, and make it so that nobody has to re-write their programs? If BUS1 is different than DBUS, it completely defeats the entire point of the venture.

Dbus can still be implemented on top of bus1 for better performance and security. It just requires a slightly thicker wrapper since they don't want dbus specific serialization in the kernel.

[Guest]

Can somebody explain the point of BUS1? Wasn't the reason for KDBUS to move DBUS to the kernel for speed/security reasons, and make it so that nobody has to re-write their programs? If BUS1 is different than DBUS, it completely defeats the entire point of the venture.

At least in KDBUS, the reason was so dbus can be available from the beginning of the boot sequence.

[trek]

I hope there will be a simple method to make firewalls on the system bus or this will became the next big security hole

[nanonyme]

At least in KDBUS, the reason was so dbus can be available from the beginning of the boot sequence.

Yeah, it will be really interesting if they end up wanting to start it in initrd in userspace and survive transition to normal root.

[timtas]

Isn't the naming wrong, anyway? Since systemd is pid1 and this ipc implementation runs in-kernel, they should have called it bus0. I guess someone just really likes being "1".

[timofonic]

Isn't the naming wrong, anyway? Since systemd is pid1 and this ipc implementation runs in-kernel, they should have called it bus0. I guess someone just really likes being "1".

11111111111111111111one (I had to do it, sorry)

Maybe it can potentially remove dependency on systemd running in PID1? That would be simply amazing.

[starshipeleven]

what's the purpose of kdbus dbus bus1!?

http://www.bus1.org/
Bus1 is a subsystem to provide object-oriented Inter-Process Communication on Linux. It is a lightweight and scalable way for services and operating system tasks to share signals, data and resources; while at the same time allowing modularization, privilege separation, information hiding and isolation.

They are a standardized "messenger" used by programs to coordinate with each other without knowing every other application they might need to talk with.

[interested]

Yes, but Linus will never ever accept kdbus upstream because it is bad by design (and it has to if it wants to be retro compatible), so they had to write a completely new protocol.

That is simply untrue. Linus T. explicitly said on LKML that he would merge kdbus if asked. You can find Linus actually saying this on the LKML. So whoever told the above was simply making things up.

[interested]

I hope there will be a simple method to make firewalls on the system bus or this will became the next big security hole

One of the reasons for having kernel IPC like bus1 is exactly the increased security since it gives LSMs (Linux Security Modules) a chance to eg. inspect and control bus messages from the kernel, instead of from the much more insecure user space.

All in all bus1 will be a security benefit that improves the current situation.

[pal666]

It's JustAnotherIPC at this point

it is not just another ipc. it is bus1. you could read its docs if you want to know difference