[Samba] domain-free multi-user use cases

[Jeremy Allison]

On Sat, Oct 23, 2021 at 07:43:01PM -0400, Eric Levy via samba wrote:
>It seems the first scenario you describe is simply several users each
>creating their own single-user mount, that is, several simultaneous
>uses in class (1).
>
>The second describes a Windows client, and it hasn't been explained
>whether the same concept would transfer to a Linux client.
>
>Can a Linux client mount (e.g. as root) a remote Samba share such that
>files on the server owned by user1, user2, and so on, show
>correspondingly on the client as owned by user1, user2, and so on?

man mount.cifs - options:

        multiuser
               Map  user  accesses to individual credentials when accessing the
               server. By default, CIFS mounts only use a single  set  of  user
               credentials (the mount credentials) when accessing a share. With
               this option, the client instead creates a new session  with  the
               server using the user's credentials whenever a new user accesses
               the mount.  Further accesses by that user will  also  use  those
               credentials.  Because  the  kernel  cannot prompt for passwords,
               multiuser mounts are limited to mounts using sec=  options  that
               don't require passwords.

               With this change, it's feasible for the server to handle permis‐
               sions enforcement, so this option also implies noperm . Further‐
               more,  when  unix extensions aren't in use and the administrator
               has not overridden ownership using the  uid=  or  gid=  options,
               ownership  of  files  is presented as the current user accessing
               the share.