visudo
(1m)
名前
visudo - edit the sudoers file
形式
visudo [-chqsV] [-f sudoers]
説明
Maintenance Commands VISUDO(1m)
NAME
visudo - edit the sudoers file
SYNOPSIS
visudo [-chqsV] [-f sudoers]
DESCRIPTION
visudo edits the sudoers file in a safe fashion, analogous
to vipw(1m). visudo locks the sudoers file against multiple
simultaneous edits, provides basic sanity checks, and checks
for parse errors. If the sudoers file is currently being
edited you will receive a message to try again later.
There is a hard-coded list of one or more editors that
visudo will use set at compile-time that may be overridden
via the editor sudoers Default variable. This list defaults
to /usr/bin/vi. Normally, visudo does not honor the VISUAL
or EDITOR environment variables unless they contain an
editor in the aforementioned editors list. However, if
visudo is configured with the --with-env-editor option or
the env_editor Default variable is set in sudoers, visudo
will use any the editor defines by VISUAL or EDITOR. Note
that this can be a security hole since it allows the user to
execute any program they wish simply by setting VISUAL or
EDITOR.
visudo parses the sudoers file after the edit and will not
save the changes if there is a syntax error. Upon finding
an error, visudo will print a message stating the line
number(s) where the error occurred and the user will receive
the ``What now?'' prompt. At this point the user may enter
`e' to re-edit the sudoers file, `x' to exit without saving
the changes, or `Q' to quit and save changes. The `Q'
option should be used with extreme care because if visudo
believes there to be a parse error, so will sudo and no one
will be able to sudo again until the error is fixed. If `e'
is typed to edit the sudoers file after a parse error has
been detected, the cursor will be placed on the line where
the error occurred (if the editor supports this feature).
The options are as follows:
-c Enable check-only mode. The existing sudoers
file will be checked for syntax errors, owner
and mode. A message will be printed to the
standard output describing the status of sudoers
unless the -q option was specified. If the
check completes successfully, visudo will exit
with a value of 0. If an error is encountered,
visudo will exit with a value of 1.
-f sudoers
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Specify and alternate sudoers file location.
With this option visudo will edit (or check) the
sudoers file of your choice, instead of the
default, /etc/sudoers. The lock file used is
the specified sudoers file with ``.tmp''
appended to it. In check-only mode only, the
argument to -f may be `-', indicating that
sudoers will be read from the standard input.
-h The -h (help) option causes visudo to print a
short help message to the standard output and
exit.
-q Enable quiet mode. In this mode details about
syntax errors are not printed. This option is
only useful when combined with the -c option.
-s Enable strict checking of the sudoers file. If
an alias is used before it is defined, visudo
will consider this a parse error. Note that it
is not possible to differentiate between an
alias and a host name or user name that consists
solely of uppercase letters, digits, and the
underscore (`_') character.
-V The -V (version) option causes visudo to print
its version number and exit.
ENVIRONMENT
The following environment variables may be consulted
depending on the value of the editor and env_editor sudoers
settings:
VISUAL Invoked by visudo as the editor to use
EDITOR Used by visudo if VISUAL is not set
FILES
/etc/sudoers List of who can run what
/etc/sudoers.tmp Lock file for visudo
DIAGNOSTICS
sudoers file busy, try again later.
Someone else is currently editing the sudoers file.
/etc/sudoers.tmp: Permission denied
You didn't run visudo as root.
Can't find you in the passwd database
Your user ID does not appear in the system passwd
file.
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Warning: {User,Runas,Host,Cmnd}_Alias referenced but not
defined
Either you are trying to use an undeclared
{User,Runas,Host,Cmnd}_Alias or you have a user or
host name listed that consists solely of uppercase
letters, digits, and the underscore (`_') character.
In the latter case, you can ignore the warnings (sudo
will not complain) . In -s (strict) mode these are
errors, not warnings.
Warning: unused {User,Runas,Host,Cmnd}_Alias
The specified {User,Runas,Host,Cmnd}_Alias was defined
but never used. You may wish to comment out or remove
the unused alias. In -s (strict) mode this is an
error, not a warning.
Warning: cycle in {User,Runas,Host,Cmnd}_Alias
The specified {User,Runas,Host,Cmnd}_Alias includes a
reference to itself, either directly or through an
alias it includes. This is only a warning by default
as sudo will ignore cycles when parsing the sudoers
file.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | security/sudo |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
vi(1), sudoers(4), sudo(1m), vipw(1m)
AUTHORS
Many people have worked on sudo over the years; this version
consists of code written primarily by:
Todd C. Miller
See the CONTRIBUTORS file in the sudo distribution
(http://www.sudo.ws/sudo/contributors.html) for an
exhaustive list of people who have contributed to sudo.
CAVEATS
There is no easy way to prevent a user from gaining a root
shell if the editor used by visudo allows shell escapes.
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BUGS
If you feel you have found a bug in visudo, please submit a
bug report at http://www.sudo.ws/sudo/bugs/
SUPPORT
Limited free support is available via the sudo-users mailing
list, see http://www.sudo.ws/mailman/listinfo/sudo-users to
subscribe or search the archives.
DISCLAIMER
visudo is provided ``AS IS'' and any express or implied
warranties, including, but not limited to, the implied
warranties of merchantability and fitness for a particular
purpose are disclaimed. See the LICENSE file distributed
with sudo or http://www.sudo.ws/sudo/license.html for
complete details.
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://www.sudo.ws/sudo/dist/sudo-1.8.6p7.tar.gz
Further information about this software can be found on the
open source community website at http://www.sudo.ws/.
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