.\" DO NOT EDIT THIS FILE, IT IS NOT THE MASTER!
.\" IT IS GENERATED AUTOMATICALLY FROM visudo.mdoc.in
.\"
.\" Copyright (c) 1996,1998-2005, 2007-2017
.\"	Todd C. Miller <Todd.Miller@courtesan.com>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" Sponsored in part by the Defense Advanced Research Projects
.\" Agency (DARPA) and Air Force Research Laboratory, Air Force
.\" Materiel Command, USAF, under agreement number F39502-99-1-0512.
.\"
.TH "VISUDO" "8" "February 22, 2017" "Sudo @PACKAGE_VERSION@" "System Manager's Manual"
.nh
.if n .ad l
.SH "NAME"
\fBvisudo\fR
\- edit the sudoers file
.SH "SYNOPSIS"
.HP 7n
\fBvisudo\fR
[\fB\-chqsV\fR]
[\fB\-f\fR\ \fIsudoers\fR]
[\fB\-x\fR\ \fIoutput_file\fR]
.SH "DESCRIPTION"
\fBvisudo\fR
edits the
\fIsudoers\fR
file in a safe fashion, analogous to
vipw(@mansectsu@).
\fBvisudo\fR
locks the
\fIsudoers\fR
file against multiple simultaneous edits, provides basic sanity checks,
and checks for parse errors.
If the
\fIsudoers\fR
file is currently being edited you will receive a message to try again later.
.PP
There is a hard-coded list of one or more editors that
\fBvisudo\fR
will use set at compile-time that may be overridden via the
\fIeditor\fR
\fIsudoers\fR
\fRDefault\fR
variable.
This list defaults to
\fR@editor@\fR.
Normally,
\fBvisudo\fR
does not honor the
\fRVISUAL\fR
or
\fREDITOR\fR
environment variables unless they contain an editor in the aforementioned
editors list.
However, if
\fBvisudo\fR
is configured with the
\fR--with-env-editor\fR
option or the
\fIenv_editor\fR
\fRDefault\fR
variable is set in
\fIsudoers\fR,
\fBvisudo\fR
will use any the editor defines by
\fRVISUAL\fR
or
\fREDITOR\fR.
Note that this can be a security hole since it allows the user to
execute any program they wish simply by setting
\fRVISUAL\fR
or
\fREDITOR\fR.
.PP
\fBvisudo\fR
parses the
\fIsudoers\fR
file after the edit and will
not save the changes if there is a syntax error.
Upon finding an error,
\fBvisudo\fR
will print a message stating the line number(s)
where the error occurred and the user will receive the
\(LqWhat now?\(Rq
prompt.
At this point the user may enter
\(oqe\(cq
to re-edit the
\fIsudoers\fR
file,
\(oqx\(cq
to exit without saving the changes, or
\(oqQ\(cq
to quit and save changes.
The
\(oqQ\(cq
option should be used with extreme care because if
\fBvisudo\fR
believes there to be a parse error, so will
\fBsudo\fR
and no one
will be able to run
\fBsudo\fR
again until the error is fixed.
If
\(oqe\(cq
is typed to edit the
\fIsudoers\fR
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).
.PP
The options are as follows:
.TP 12n
\fB\-c\fR, \fB\--check\fR
Enable
\fIcheck-only\fR
mode.
The existing
\fIsudoers\fR
file will be
checked for syntax errors, owner and mode.
A message will be printed to the standard output describing the status of
\fIsudoers\fR
unless the
\fB\-q\fR
option was specified.
If the check completes successfully,
\fBvisudo\fR
will exit with a value of 0.
If an error is encountered,
\fBvisudo\fR
will exit with a value of 1.
.TP 12n
\fB\-f\fR \fIsudoers\fR, \fB\--file\fR=\fIsudoers\fR
Specify an alternate
\fIsudoers\fR
file location.
With this option,
\fBvisudo\fR
will edit (or check) the
\fIsudoers\fR
file of your choice,
instead of the default,
\fI@sysconfdir@/sudoers\fR.
The lock file used is the specified
\fIsudoers\fR
file with
\(Lq\.tmp\(Rq
appended to it.
In
\fIcheck-only\fR
mode only, the argument to
\fB\-f\fR
may be
\(oq-\(cq,
indicating that
\fIsudoers\fR
will be read from the standard input.
.TP 12n
\fB\-h\fR, \fB\--help\fR
Display a short help message to the standard output and exit.
.TP 12n
\fB\-q\fR, \fB\--quiet\fR
Enable
\fIquiet\fR
mode.
In this mode details about syntax errors are not printed.
This option is only useful when combined with
the
\fB\-c\fR
option.
.TP 12n
\fB\-s\fR, \fB\--strict\fR
Enable
\fIstrict\fR
checking of the
\fIsudoers\fR
file.
If an alias is referenced but not actually defined
or if there is a cycle in an alias,
\fBvisudo\fR
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
(\(oq_\(cq)
character.
.TP 12n
\fB\-V\fR, \fB\--version\fR
Print the
\fBvisudo\fR
and
\fIsudoers\fR
grammar versions and exit.
.TP 12n
\fB\-x\fR \fIoutput_file\fR, \fB\--export\fR=\fIoutput_file\fR
Export a
\fIsudoers\fR
in JSON format and write it to
\fIoutput_file\fR.
If
\fIoutput_file\fR
is
\(oq-\(cq,
the exported
\fIsudoers\fR
policy will be written to the standard output.
By default,
\fI@sysconfdir@/sudoers\fR
(and any files it includes) will be exported.
The
\fB\-f\fR
option can be used to specify a different
\fIsudoers\fR
file to export.
The exported format is intended to be easier for third-party
applications to parse than the traditional
\fIsudoers\fR
format.
The various values have explicit types which removes much of the
ambiguity of the
\fIsudoers\fR
format.
.SS "Debugging and sudoers plugin arguments"
\fBvisudo\fR
versions 1.8.4 and higher support a flexible debugging framework
that is configured via
\fRDebug\fR
lines in the
sudo.conf(@mansectform@)
file.
.PP
Starting with
\fBsudo\fR
1.8.12,
\fBvisudo\fR
will also parse the arguments to the
\fIsudoers\fR
plugin to override the default
\fIsudoers\fR
path name, UID, GID and file mode.
These arguments, if present, should be listed after the path to the plugin
(i.e.\& after
\fIsudoers.so\fR).
Multiple arguments may be specified, separated by white space.
For example:
.nf
.sp
.RS 6n
Plugin sudoers_policy sudoers.so sudoers_mode=0400
.RE
.fi
.PP
The following arguments are supported:
.TP 10n
sudoers_file=pathname
The
\fIsudoers_file\fR
argument can be used to override the default path to the
\fIsudoers\fR
file.
.TP 10n
sudoers_uid=uid
The
\fIsudoers_uid\fR
argument can be used to override the default owner of the sudoers file.
It should be specified as a numeric user ID.
.TP 10n
sudoers_gid=gid
The
\fIsudoers_gid\fR
argument can be used to override the default group of the sudoers file.
It must be specified as a numeric group ID (not a group name).
.TP 10n
sudoers_mode=mode
The
\fIsudoers_mode\fR
argument can be used to override the default file mode for the sudoers file.
It should be specified as an octal value.
.PP
For more information on configuring
sudo.conf(@mansectform@),
please refer to its manual.
.SH "ENVIRONMENT"
The following environment variables may be consulted depending on
the value of the
\fIeditor\fR
and
\fIenv_editor\fR
\fIsudoers\fR
settings:
.TP 17n
\fRVISUAL\fR
Invoked by
\fBvisudo\fR
as the editor to use
.TP 17n
\fREDITOR\fR
Used by
\fBvisudo\fR
if
\fRVISUAL\fR
is not set
.SH "FILES"
.TP 26n
\fI@sysconfdir@/sudo.conf\fR
Sudo front end configuration
.TP 26n
\fI@sysconfdir@/sudoers\fR
List of who can run what
.TP 26n
\fI@sysconfdir@/sudoers.tmp\fR
Lock file for visudo
.SH "DIAGNOSTICS"
In addition to reporting
\fIsudoers\fR
parse errors,
\fBvisudo\fR
may produce the following messages:
.TP 6n
\fRsudoers file busy, try again later.\fR
Someone else is currently editing the
\fIsudoers\fR
file.
.TP 6n
\fR@sysconfdir@/sudoers.tmp: Permission denied\fR
You didn't run
\fBvisudo\fR
as root.
.TP 6n
\fRyou do not exist in the passwd database\fR
Your user ID does not appear in the system passwd database.
.TP 6n
\fRWarning: {User,Runas,Host,Cmnd}_Alias referenced but not defined\fR
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
(\(oq_\(cq)
character.
In the latter case, you can ignore the warnings
(\fBsudo\fR
will not complain)
\&.
The message is prefixed with the path name of the
\fIsudoers\fR
file and the line number where the undefined alias was used.
In
\fB\-s\fR
(strict) mode these are errors, not warnings.
.TP 6n
\fRWarning: unused {User,Runas,Host,Cmnd}_Alias\fR
The specified {User,Runas,Host,Cmnd}_Alias was defined but never
used.
The message is prefixed with the path name of the
\fIsudoers\fR
file and the line number where the unused alias was defined.
You may wish to comment out or remove the unused alias.
.TP 6n
\fRWarning: cycle in {User,Runas,Host,Cmnd}_Alias\fR
The specified {User,Runas,Host,Cmnd}_Alias includes a reference to
itself, either directly or through an alias it includes.
The message is prefixed with the path name of the
\fIsudoers\fR
file and the line number where the cycle was detected.
This is only a warning unless
\fBvisudo\fR
is run in
\fB\-s\fR
(strict) mode as
\fBsudo\fR
will ignore cycles when parsing
the
\fIsudoers\fR
file.
.TP 6n
\fRunknown defaults entry \&"name\&"\fR
The
\fIsudoers\fR
file contains a
\fRDefaults\fR
setting not recognized by
\fBvisudo\fR.
.TP 6n
\fR@sysconfdir@/sudoers: input and output files must be different\fR
The
\fB\-x\fR
flag was used and the specified
\fIoutput_file\fR
has the same path name as the
\fIsudoers\fR
file to export.
.SH "SEE ALSO"
vi(1),
sudo.conf(@mansectform@),
sudoers(@mansectform@),
sudo(@mansectsu@),
vipw(@mansectsu@)
.SH "AUTHORS"
Many people have worked on
\fBsudo\fR
over the years; this version consists of code written primarily by:
.sp
.RS 6n
Todd C. Miller
.RE
.PP
See the CONTRIBUTORS file in the
\fBsudo\fR
distribution (https://www.sudo.ws/contributors.html) for an
exhaustive list of people who have contributed to
\fBsudo\fR.
.SH "CAVEATS"
There is no easy way to prevent a user from gaining a root shell if
the editor used by
\fBvisudo\fR
allows shell escapes.
.SH "BUGS"
If you feel you have found a bug in
\fBvisudo\fR,
please submit a bug report at https://bugzilla.sudo.ws/
.SH "SUPPORT"
Limited free support is available via the sudo-users mailing list,
see https://www.sudo.ws/mailman/listinfo/sudo-users to subscribe or
search the archives.
.SH "DISCLAIMER"
\fBvisudo\fR
is provided
\(LqAS IS\(Rq
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
\fBsudo\fR
or https://www.sudo.ws/license.html for complete details.
