Subject: Re: Need some advice regarding portable user IDs
To: None <justin@apple.com>
From: Wes Peters <wes@softweyr.com>
List: tech-userlevel
Date: 08/19/1999 23:17:13
"Justin C. Walker" wrote:
> 
> My understanding of File Sharing [for Mac OS 8]is that (a) Mac OS
> doesn't understand identity, permissions, etc., so it can't "talk"
> about them; and (b) when you share a volume from a remote server, you
> "login" to that volume using a mechanism supported by the server.

For NFS, this is typically pcnfsd on the PC side, and a pcnfsd client on
the Mac.

> The client system isn't involved.  Since you, at the keyboard, are
> really the only user of that system, the issue of what "another
> logged-in user" can do is moot.

This is not true if the user is someone else 10 minutes later.

> Note that although the "enhanced" HFS supports credentials (i.e,
> owner and group identity), Mac OS doesn't use this capability, and
> wouldn't know what to do with a volume that had this info filled in
> (i.e., can't make use of it).
> 
> The whole issue of associating identity with permission is a bit
> perplexing.  DCE attempted to solve this problem, and it got quickly
> out of hand.  Regardless of whether you are using 32-bit integers, or
> 8-character login names, there's little or no guarantee that when
> you move a device containing this info from one site to another, the
> "mapping" from that identity to who you are will remain valid.

There is no guarantee.  My uid here is 1001 because mine was the first
account added to each of the FreeBSD machines here.  At work, it's my
employee number.

> In the meanwhile, there ought to be a simple version of this problem
> that we can solve :-}.  I think I'll get down off this soap box for
> a bit...

pcnfsd?  Open source versions have existed for years, at least the server
side.  If you have the server, a client shouldn't be all that hard to do.

-- 
            "Where am I, and what am I doing in this handbasket?"

Wes Peters                                                         Softweyr LLC
http://softweyr.com/                                           wes@softweyr.com