[74] in Info-AFS_Redistribution
Re: A question on protection semantics.
daemon@ATHENA.MIT.EDU (daemon@ATHENA.MIT.EDU)
Tue Feb 12 08:32:25 1991
Date: Tue, 12 Feb 1991 08:08:15 -0500 (EST)
From: Tony_Mauro@transarc.com
To: Info-AFS@transarc.com, Christer Bernerus <bernerus@cs.chalmers.se>
In-Reply-To: <sbgevW61408I46v34l@cs.chalmers.se>
I believe that Phil might already have explained why you are experiencing
this problem with writing when the "r" bit is not turned on. I just
wanted to point out that this 'feature' is documented, though it is perfectly
understandable that you did not notice it among the 600+ pages of the
System Adminisitrator's guide. On page 2-2, the last bulleted item
in section 2.1.1.1 says:
You cannot make an AFS file "write only" as is possible by turning on only
the w mode bit on a UNIX file. To exercise the ACL WRITE right, the possessor
must also have the LOOKUP and READ rights.
The second bullet in that section points you to section 19.10 for
a discussion of how AFS ACL rights interact with mode bits. Section
19.10 explains that the "r" owner bit must be on in order for
anyone to exercise the ACL READ right. Combining the two facts leads
to the conclusion that in order to write an AFS file, the owner "r"
mode bit must be on and the READ right must be granted on the ACL.
Hope this helps.
Tony Mauro
Documenter, AFS
