At 18:23 11/12/01, Hans Reiser wrote:
Stephen C. Tweedie wrote:
The proposal defines two "families" of attribute entities: attribute
If you have given it some thought, which your writing hints you may have,
can you say a little about supporting NT SIDS and NT ACLs by Linux, and
how that can be hard and easy?
families and name families.
An attribute family might be ATR_USER or ATR_SYSTEM to specify that we
are dealing with arbitrary user or system named extended attributes,
or ATR_POSIXACL to specify POSIX-semantics ACLs. Obviously, this can
be extended to other ACL semantics without revving the API --- a new
attribute family would be all that is needed.
The "name family" is the other part of the equation. Attributes in
the ATR_USER or ATR_SYSTEM families might be named with counted
strings, so they would have names in the ANAME_STRING name family.
POSIX ACLs, however, have a different namespace: ANAME_UID or
ANAME_GID. The API cleanly deals with the difference between user and
group ACLs. It also makes it easy to add support later on for more
complex operations: if we want to add NT SID support to ext2 ACLs so
that Samba and local accesses get the same access control, we can pass
ANAME_NTSID names to the ATR_POSIXACL attribute family without
changing the API.
One of my programmers is arguing that NT (as opposed to POSIX) ACL support
is harder than I imagine due to SIDS, and.... your view would be interesting.
SIDs are nothing but user ids so you just require the user to pass a
mapping between SIDs and Linux user&group ids at mount time and that
problem is solved.
I am told samba already has support for SIDs so it can't be that difficult. (-:
"I've not lost my mind. It's backed up on tape somewhere." - Unknown
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