User: Password:
Subscribe / Log in / New account

Releasing Samba 4

Releasing Samba 4

Posted Dec 2, 2011 18:51 UTC (Fri) by jra (subscriber, #55261)
In reply to: Releasing Samba 4 by trasz
Parent article: Releasing Samba 4

You're obviosly unaware of the acl_xattr module shipped in modern Samba, and used by most OEMs.

This stores "pristine" Windows ACLs in an EA on the filesystem, and consults them before allowing access to the underlying file/directory. The mapping to underlying POSIX ACLs (for systems that don't support them) is done underneath this layer for compatibility with NFSv3 and system process accessing the same files.

Samba of course has a full mapping into NFSv4 (ZFS, or GPFS) ACLs, which will be supported on Linux once the "RichACLs" patch is accepted into the kernel.

So yes, ACLs *do* work in the general case in Samba, and many successful OEMs ship with them turned on.


(Log in to post comments)

Releasing Samba 4

Posted Dec 5, 2011 9:40 UTC (Mon) by trasz (guest, #45786) [Link]

Yup, my bad. I didn't know about this module.

Releasing Samba 4

Posted Feb 8, 2012 7:19 UTC (Wed) by kaiser (guest, #82799) [Link]

It's my experience that most users want ACLs which interoperate with the native filesystem as well as NFSv3/v4--in other words, they want their permissions to be the same regardless of access protocol. In this respect I think Sun and Isilon did it right by integrating ACL/SID support directly into the kernel.

This fixes some minor interop. nits (group owners of files, for example) but also allows the Windows privilege model to be integrated as a first class citizen in the OS, and most importantly, allows for SIDs to be stored natively as the user's in-kernel credentials, which is a real boon for identity management/mapping across protocols, and for group policy (e.g. local groups). As a bonus, this allows any userspace CIFS processes to run without escalated privilege (e.g. switching to root for take ownership) which can be seen as a security risk.

Copyright © 2017, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds