[Review Request] libwbclient-sssd

[Volker Lendecke]

On Tue, Jun 24, 2014 at 11:27:55AM +0200, Sumit Bose wrote:
> > of this rush to implement the protocol in winbind from scratch? At least
> > the non-mmap piece looks not too complicated. If sssd has no resources
> > to spend, maybe someone could re-implement this in Samba proper.
> 
> My plan is to put all coding and decoding in a library so that the wire
> protocol becomes opaque to the caller. I think this is easier and more
> reliable in the long run than reimplementing it.

True. I just thought that if the SSSD project has no
inclination/manpower/focus to do this, you could with your
Samba hat on be faster by reimplementing this. I could 100%
understand if the SSSD project people have no real genuine
interest in sharing the protocol implementation, and a
second source implementation can only improve the situation.

> > What protocol do you have in mind? Samba already implements
> > an abundance of RPC-style protocols that are capable of
> > async requests, maybe we can ride on one of those? The sssd
> 
> Yes, I'm sure there is a suitable one, but I'm sure as well that you and
> the other members of the samba team have a much better understanding which
> of them is the best here to replace the current winbind API.

I don't have anything specific in mind. It must be simple
and ideally not depend on anything external. By the way,
what protocol does nscd speak? Is that reusable?

> Iirc there is only one left, nevertheless since the POSIX NSS calls are
> synchronous there is not much need to make the client async here. But it
> has to be thread safe because that's what people are using to get around
> the POSIX NSS limitations here.

Sure. However, you probably want to multiplex concurrent
synchronous threaded calls over a single socket, so you need
the multiplex ID again.

> FYI for more complex queries the next SSSD release will have a new
> provider called InfoPipe which uses the D-Bus protocol. But I guess this
> is SSSD specific and will not have much overlaps with samba or winbind
> with respect to the protocol.

What additional information goes over this protocol?

Thanks,

Volker

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