Manual Pages  — SETFACL

setfacl – set ACL information

SYNOPSIS DESCRIPTION POSIX.1e ACL ENTRIES NFSv4 ACL ENTRIES EXIT STATUS EXAMPLES SEE ALSO STANDARDS HISTORY AUTHORS

setfacl [-R [-H | -L | -P]] [-bdhkn] [-a position entries] [-m entries] [-M file] [-x entries | position] [-X file] [file ...]

The setfacl utility sets discretionary access control information on the specified file(s). If no files are specified, or the list consists of the only '-', the file names are taken from the standard input.

The following options are available:

-a position entries
	Modify the ACL on the specified files by inserting new ACL entries specified in entries, starting at position position, counting from zero. This option is only applicable to NFSv4 ACLs.
-b
	Remove all ACL entries except for the ones synthesized from the file mode - the three mandatory entries in case of POSIX.1e ACL. If the POSIX.1e ACL contains a "mask" entry, the permissions of the "group" entry in the resulting ACL will be set to the permission associated with both the "group" and "mask" entries of the current ACL.
-d
	The operations apply to the default ACL entries instead of access ACL entries. Currently only directories may have default ACL's. This option is not applicable to NFSv4 ACLs.
-h
	If the target of the operation is a symbolic link, perform the operation on the symbolic link itself, rather than following the link.
-H
	If the -R option is specified, symbolic links on the command line are followed and hence unaffected by the command. (Symbolic links encountered during tree traversal are not followed.)
-k
	Delete any default ACL entries on the specified files. It is not considered an error if the specified files do not have any default ACL entries. An error will be reported if any of the specified files cannot have a default entry (i.e., non-directories). This option is not applicable to NFSv4 ACLs.
-L
	If the -R option is specified, all symbolic links are followed.
-m entries
	Modify the ACL on the specified file. New entries will be added, and existing entries will be modified according to the entries argument. For NFSv4 ACLs, it is recommended to use the -a and -x options instead.
-M file
	Modify the ACL entries on the specified files by adding new ACL entries and modifying existing ACL entries with the ACL entries specified in the file file. If file is -, the input is taken from stdin.
-n
	Do not recalculate the permissions associated with the ACL mask entry. This option is not applicable to NFSv4 ACLs.
-P
	If the -R option is specified, no symbolic links are followed. This is the default.
-R
	Perform the action recursively on any specified directories. When modifying or adding NFSv4 ACL entries, inheritance flags are applied only to directories.
-x entries | position
	If entries is specified, remove the ACL entries specified there from the access or default ACL of the specified files. Otherwise, remove entry at index position, counting from zero.
-X file
	Remove the ACL entries specified in the file file from the access or default ACL of the specified files.

The above options are evaluated in the order specified on the command-line.

An NFSv4 ACL entry contains four or five colon-separated fields: an ACL tag, an ACL qualifier (only for "user" and "group" tags), discretionary access permissions, ACL inheritance flags, and ACL type:

ACL tag
	The ACL tag specifies the ACL entry type and consists of one of the following: "user" or ‘u’ specifying the access granted to the specified user; "group" or ‘g’ specifying the access granted to the specified group; "owner@" specifying the access granted to the owner of the file; "group@" specifying the access granted to the file owning group; "everyone@" specifying everyone. Note that "everyone@" is not the same as traditional Unix "other" - it means, literally, everyone, including file owner and owning group.
ACL qualifier
	The ACL qualifier field describes the user or group associated with the ACL entry. It may consist of one of the following: uid or user name, or gid or group name. In entries whose tag type is one of "owner@", "group@", or "everyone@", this field is omitted altogether, including the trailing comma.
access permissions
	Access permissions may be specified in either short or long form. Short and long forms may not be mixed. Permissions in long form are separated by the ‘/’ character; in short form, they are concatenated together. Valid permissions are:

Short	Long
r	read_data
w	write_data
x	execute
p	append_data
D	delete_child
d	delete
a	read_attributes
A	write_attributes
R	read_xattr
W	write_xattr
c	read_acl
C	write_acl
o	write_owner
s	synchronize

In addition, the following permission sets may be used:

Set	Permissions
full_set	all permissions, as shown above
modify_set
	all permissions except write_acl and write_owner
read_set	read_data, read_attributes, read_xattr and read_acl
write_set	write_data, append_data, write_attributes and write_xattr

ACL inheritance flags
	Inheritance flags may be specified in either short or long form. Short and long forms may not be mixed. Access flags in long form are separated by the ‘/’ character; in short form, they are concatenated together. Valid inheritance flags are:

Short	Long
f	file_inherit
d	dir_inherit
i	inherit_only
n	no_propagate
I	inherited

Other than the "inherited" flag, inheritance flags may be only set on directories.

ACL type
	The ACL type field is either "allow" or "deny".

ACL entries applied from a file using the -M or -X options shall be of the following form: one ACL entry per line, as previously specified; whitespace is ignored; any text after a ‘#’ is ignored (comments).

NFSv4 ACL entries are evaluated in their visible order.

Multiple ACL entries specified on the command line are separated by commas.

Note that the file owner is always granted the read_acl, write_acl, read_attributes, and write_attributes permissions, even if the ACL would deny it.

The utility exits 0 on success, and >0 if an error occurs.

    setfacl -d -m u::rwx,g::rx,o::rx,mask::rwx dir

    setfacl -d -m g:admins:rwx dir

The first command sets the mandatory elements of the POSIX.1e default ACL. The second command specifies that users in group admins can have read, write, and execute permissions for directory named "dir". It should be noted that any files or directories created underneath "dir" will inherit these default ACLs upon creation.

    setfacl -m u::rwx,g:mail:rw file

Sets read, write, and execute permissions for the file owner's POSIX.1e ACL entry and read and write permissions for group mail on file.

    setfacl -m owner@:rwxp::allow,g:mail:rwp::allow file

Semantically equal to the example above, but for NFSv4 ACL.

    setfacl -M file1 file2

Sets/updates the ACL entries contained in file1 on file2.

    setfacl -x g:mail:rw file

Remove the group mail POSIX.1e ACL entry containing read/write permissions from file.

    setfacl -x0 file

Remove the first entry from the NFSv4 ACL from file.

    setfacl -bn file

Remove all "access" ACL entries except for the three required from file.

    getfacl file1 | setfacl -b -n -M - file2

Copy ACL entries from file1 to file2.

The setfacl utility is expected to be IEEE Std 1003.2c compliant.

Extended Attribute and Access Control List support was developed as part of the TrustedBSD Project and introduced in FreeBSD 5.0 . NFSv4 ACL support was introduced in FreeBSD 8.1 .

The setfacl utility was written by Chris D. Faulhaber <Mt jedgar@fxp.org>. NFSv4 ACL support was implemented by Edward Tomasz Napierala <Mt trasz@FreeBSD.org>.