FS_SETACL(1) AFS Command Reference FS_SETACL(1)NAMEfs_setacl - Sets the ACL for a directory
SYNOPSIS
fs setacl -dir <directory>+ -acl <access list entries>+
[-clear] [-negative] [-id] [-if] [-help]
fs sa -d <directory>+ -a <access list entries>+
[-c] [-n] [-id] [-if] [-h]
fs seta -d <directory>+ -a <access list entries>+
[-c] [-n] [-id] [-if] [-h]
DESCRIPTION
The fs setacl command adds the access control list (ACL) entries
specified with the -acl argument to the ACL of each directory named by
the -dir argument.
If the -dir argument designates a pathname in DFS filespace (accessed
via the AFS/DFS Migration Toolkit Protocol Translator), it can be a
file as well as a directory. The ACL must already include an entry for
"mask_obj", however.
Only user and group entries are acceptable values for the -acl
argument. Do not place machine entries (IP addresses) directly on an
ACL; instead, make the machine entry a group member and place the group
on the ACL.
To completely erase the existing ACL before adding the new entries,
provide the -clear flag. To add the specified entries to the "Negative
rights" section of the ACL (deny rights to specified users or groups),
provide the -negative flag.
To display an ACL, use the fs listacl command. To copy an ACL from one
directory to another, use the fs copyacl command.
CAUTIONS
If the ACL already grants certain permissions to a user or group, the
permissions specified with the fs setacl command replace the existing
permissions, rather than being added to them.
Setting negative permissions is generally unnecessary and not
recommended. Simply omitting a user or group from the "Normal rights"
section of the ACL is normally adequate to prevent access. In
particular, note that it is futile to deny permissions that are granted
to members of the system:anyuser group on the same ACL; the user needs
only to issue the unlog command to receive the denied permissions.
When including the -clear option, be sure to reinstate an entry for
each directory's owner that includes at least the "l" (lookup)
permission. Without that permission, it is impossible to resolve the
"dot" (".") and "dot dot" ("..") shorthand from within the directory.
(The directory's owner does implicitly have the "a" (administer)
permission even on a cleared ACL, but must know to use it to add other
permissions.)
OPTIONS-dir <directory>+
Names each AFS directory, or DFS directory or file, for which the
set the ACL. Partial pathnames are interpreted relative to the
current working directory.
Specify the read/write path to each directory (or DFS file), to
avoid the failure that results from attempting to change a read-
only volume. By convention, the read/write path is indicated by
placing a period before the cell name at the pathname's second
level (for example, /afs/.abc.com). For further discussion of the
concept of read/write and read-only paths through the filespace,
see the fs mkmount reference page.
-acl <access list entries>+
Defines a list of one or more ACL entries, each a pair that names:
· A user name or group name as listed in the Protection Database.
· One or more ACL permissions, indicated either by combining the
individual letters or by one of the four acceptable shorthand
words.
in that order, separated by a space (thus every instance of this
argument has two parts). The accepted AFS abbreviations and
shorthand words, and the meaning of each, are as follows:
a (administer)
Change the entries on the ACL.
d (delete)
Remove files and subdirectories from the directory or move them
to other directories.
i (insert)
Add files or subdirectories to the directory by copying, moving
or creating.
k (lock)
Set read locks or write locks on the files in the directory.
l (lookup)
List the files and subdirectories in the directory, stat the
directory itself, and issue the fs listacl command to examine
the directory's ACL.
r (read)
Read the contents of files in the directory; issue the "ls -l"
command to stat the elements in the directory.
w (write)
Modify the contents of files in the directory, and issue the
UNIX chmod command to change their mode bits.
A, B, C, D, E, F, G, H
Have no default meaning to the AFS server processes, but are
made available for applications to use in controlling access to
the directory's contents in additional ways. The letters must
be uppercase.
all Equals all seven permissions ("rlidwka").
none
No permissions. Removes the user/group from the ACL, but does
not guarantee they have no permissions if they belong to groups
that remain on the ACL.
read
Equals the "r" (read) and "l" (lookup) permissions.
write
Equals all permissions except "a" (administer), that is,
"rlidwk".
It is acceptable to mix entries that combine the individual letters
with entries that use the shorthand words, but not use both types
of notation within an individual pairing of user or group and
permissions.
Granting the "l" (lookup) and "i" (insert) permissions without
granting the "w" (write) and/or "r" (read) permissions is a special
case, and grants rights approrpriate for "dropbox" directories. See
the DROPBOXES section for details.
If setting ACLs on a pathname in DFS filespace, see the DFS
documentation for the proper format and acceptable values for DFS
ACL entries.
-clear
Removes all existing entries on each ACL before adding the entries
specified with the -acl argument.
-negative
Places the specified ACL entries in the "Negative rights" section
of each ACL, explicitly denying the rights to the user or group,
even if entries on the accompanying "Normal rights" section of the
ACL grant them permissions.
This argument is not supported for DFS files or directories,
because DFS does not implement negative ACL permissions.
-id Places the ACL entries on the Initial Container ACL of each DFS
directory, which are the only file system objects for which this
flag is supported.
-if Places the ACL entries on the Initial Object ACL of each DFS
directory, which are the only file system objects for which this
flag is supported.
-help
Prints the online help for this command. All other valid options
are ignored.
DROPBOXES
If an accessing user has the "l" (read) and "i" (insert) permissions on
a directory, but not the "w" (write) and/or "r" (read) permissions, the
user is implicitly granted the ability to write and/or read any file
they create in that directory, until they close the file. This is to
allow "dropbox"-style directories to exist, where users can deposit
files, but cannot modify them later nor can they modify or read any
files deposited in the directory by other users.
Note, however, that the dropbox functionality is not perfect. The
fileserver does not have knowledge of when a file is opened or closed
on the client, and so the fileserver always allows an accessing user to
read or write to a file in a "dropbox" directory if they own the file.
While the client prevents the user from reading or modifying their
deposited file later, this is not enforced on the fileserver, and so
should not be relied on for security.
Additionally, if "dropbox" permissions are granted to "system:anyuser",
unauthenticated users may deposit files in the directory. If an
unauthenticated user deposits a file in the directory, the new file
will be owned by the unauthenticated user ID, and is thus potentially
modifiable by anyone.
In an effort to try and reduce accidentally publicizing private data,
the fileserver may refuse read requests for "dropbox" files from
unauthenticated users. As a result, depositing files as an
unauthenticated user may arbitrarily fail if "system:anyuser" has been
granted dropbox permissions. While this should be rare, it is not
completely preventable, and so for this reason relying on
unauthenticated users to be able to deposit files in a dropbox is NOT
RECOMMENDED.
EXAMPLES
The following example adds two entries to the "Normal rights" section
of the current working directory's ACL: the first entry grants "r"
(read) and "l" (lookup) permissions to the group pat:friends, while the
other (using the "write" shorthand) gives all permissions except "a"
(administer) to the user "smith".
% fs setacl -dir . -acl pat:friends rl smith write
% fs listacl -path .
Access list for . is
Normal rights:
pat:friends rl
smith rlidwk
The following example includes the -clear flag, which removes the
existing permissions (as displayed with the fs listacl command) from
the current working directory's reports subdirectory and replaces them
with a new set.
% fs listacl -dir reports
Access list for reports is
Normal rights:
system:authuser rl
pat:friends rlid
smith rlidwk
pat rlidwka
Negative rights:
terry rl
% fs setacl -clear -dir reports -acl pat all smith write system:anyuser rl
% fs listacl -dir reports
Access list for reports is
Normal rights:
system:anyuser rl
smith rlidwk
pat rlidwka
The following example use the -dir and -acl switches because it sets
the ACL for more than one directory (both the current working directory
and its public subdirectory).
% fs setacl -dir . public -acl pat:friends rli
% fs listacl -path . public
Access list for . is
Normal rights:
pat rlidwka
pat:friends rli
Access list for public is
Normal rights:
pat rlidwka
pat:friends rli
PRIVILEGE REQUIRED
The issuer must have the "a" (administer) permission on the directory's
ACL, a member of the system:administrators group, or, as a special
case, must be the UID owner of the top-level directory of the volume
containing this directory. The last provision allows the UID owner of
a volume to repair accidental ACL errors without requiring intervention
by a member of system:administrators.
Earlier versions of OpenAFS also extended implicit administer
permission to the owner of any directory. In current versions of
OpenAFS, only the owner of the top-level directory of the volume has
this special permission.
SEE ALSOfs_copyacl(1), fs_listacl(1), fs_mkmount(1)COPYRIGHT
IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.
This documentation is covered by the IBM Public License Version 1.0.
It was converted from HTML to POD by software written by Chas Williams
and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.
OpenAFS 2013-10-09 FS_SETACL(1)
