FAT, NTFS, CIFS and DOS attributes

[tridge at samba.org]

Mike,

 > If we're just thinking about MS-oriented discretionary access control then
 > I think the owner of the file is basically king and should be the only
 > normal user to that can read and write it's xattrs. So whatever namespace
 > that is (not system).

for the DACL the owner is king (the owner gets the WRITE_DAC,
READ_CONTROL and STD_DELETE access bits forced on), but for the other
parts of the full security descriptor this is not true. The owner
doesn't get to arbitrarily write to the owner_sid or SACL. Thats why I
used security.NTACL not user.NTACL.

I suppose we could have a separate user.DACL attribute, but given that
there is just one API that sets all 4 elements of the SD (with a
bitmask to say which bits to set), it made more sense to me to group
them all together. The disadvantage is that Samba needs to gain/lose
root privileges for the "set SD" call even if the client is only
asking to set the DACL.

Cheers, Tridge