1 .\" Copyright (c) 1994-1996, 1998-2005, 2007-2011
2 .\" Todd C. Miller <Todd.Miller@courtesan.com>
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24 .nr PT @password_timeout@
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149 .\" ========================================================================
151 .IX Title "SUDO @mansectsu@"
152 .TH SUDO @mansectsu@ "May 16, 2011" "1.8.1p2" "MAINTENANCE COMMANDS"
153 .\" For nroff, turn off justification. Always turn off hyphenation; it makes
154 .\" way too many mistakes in technical documents.
158 sudo, sudoedit \- execute a command as another user
160 .IX Header "SYNOPSIS"
161 \&\fBsudo\fR [\fB\-D\fR\ \fIlevel\fR] \fB\-h\fR | \fB\-K\fR | \fB\-k\fR | \fB\-V\fR
163 \&\fBsudo\fR \fB\-v\fR [\fB\-AknS\fR]
164 .if \n(BA [\fB\-a\fR\ \fIauth_type\fR]
165 [\fB\-D\fR\ \fIlevel\fR]
166 [\fB\-g\fR\ \fIgroup\ name\fR|\fI#gid\fR] [\fB\-p\fR\ \fIprompt\fR]
167 [\fB\-u\fR\ \fIuser\ name\fR|\fI#uid\fR]
169 \&\fBsudo\fR \fB\-l[l]\fR [\fB\-AknS\fR]
170 .if \n(BA [\fB\-a\fR\ \fIauth_type\fR]
171 [\fB\-D\fR\ \fIlevel\fR]
172 [\fB\-g\fR\ \fIgroup\ name\fR|\fI#gid\fR] [\fB\-p\fR\ \fIprompt\fR]
173 [\fB\-U\fR\ \fIuser\ name\fR] [\fB\-u\fR\ \fIuser\ name\fR|\fI#uid\fR] [\fIcommand\fR]
175 \&\fBsudo\fR [\fB\-AbEHnPS\fR]
176 .if \n(BA [\fB\-a\fR\ \fIauth_type\fR]
177 [\fB\-C\fR\ \fIfd\fR]
178 [\fB\-D\fR\ \fIlevel\fR]
179 .if \n(LC [\fB\-c\fR\ \fIclass\fR|\fI\-\fR]
180 [\fB\-g\fR\ \fIgroup\ name\fR|\fI#gid\fR] [\fB\-p\fR\ \fIprompt\fR]
181 .if \n(SL [\fB\-r\fR\ \fIrole\fR] [\fB\-t\fR\ \fItype\fR]
182 [\fB\-u\fR\ \fIuser\ name\fR|\fI#uid\fR]
183 [\fB\s-1VAR\s0\fR=\fIvalue\fR] [\fB\-i\fR\ |\ \fB\-s\fR] [\fIcommand\fR]
185 \&\fBsudoedit\fR [\fB\-AnS\fR]
186 .if \n(BA [\fB\-a\fR\ \fIauth_type\fR]
187 [\fB\-C\fR\ \fIfd\fR]
188 .if \n(LC [\fB\-c\fR\ \fIclass\fR|\fI\-\fR]
189 [\fB\-D\fR\ \fIlevel\fR]
190 [\fB\-g\fR\ \fIgroup\ name\fR|\fI#gid\fR] [\fB\-p\fR\ \fIprompt\fR]
191 [\fB\-u\fR\ \fIuser\ name\fR|\fI#uid\fR] file ...
193 .IX Header "DESCRIPTION"
194 \&\fBsudo\fR allows a permitted user to execute a \fIcommand\fR as the
195 superuser or another user, as specified by the security policy.
196 The real and effective uid and gid are set to match those of the
197 target user, as specified in the password database, and the group
198 vector is initialized based on the group database (unless the \fB\-P\fR
199 option was specified).
201 \&\fBsudo\fR supports a plugin architecture for security policies and
202 input/output logging. Third parties can develop and distribute
203 their own policy and I/O logging modules to work seemlessly with
204 the \fBsudo\fR front end. The default security policy is \fIsudoers\fR,
205 which is configured via the file \fI@sysconfdir@/sudoers\fR, or via
206 \&\s-1LDAP\s0. See the \s-1PLUGINS\s0 section for more information.
208 The security policy determines what privileges, if any, a user has
209 to run \fBsudo\fR. The policy may require that users authenticate
210 themselves with a password or another authentication mechanism. If
211 authentication is required, \fBsudo\fR will exit if the user's password
212 is not entered within a configurable time limit. This limit is
213 policy-specific; the default password prompt timeout for the
214 \&\fIsudoers\fR security policy is
215 .ie \n(PT \f(CW\*(C`@password_timeout@\*(C'\fR minutes.
218 Security policies may support credential caching to allow the user
219 to run \fBsudo\fR again for a period of time without requiring
220 authentication. The \fIsudoers\fR policy caches credentials for
221 \&\f(CW\*(C`@timeout@\*(C'\fR minutes, unless overridden in \fIsudoers\fR\|(@mansectform@). By
222 running \fBsudo\fR with the \fB\-v\fR option, a user can update the cached
223 credentials without running a \fIcommand\fR.
225 When invoked as \fBsudoedit\fR, the \fB\-e\fR option (described below),
228 Security policies may log successful and failed attempts to use
229 \&\fBsudo\fR. If an I/O plugin is configured, the running command's
230 input and output may be logged as well.
233 \&\fBsudo\fR accepts the following command line options:
236 Normally, if \fBsudo\fR requires a password, it will read it from the
237 user's terminal. If the \fB\-A\fR (\fIaskpass\fR) option is specified,
238 a (possibly graphical) helper program is executed to read the user's
239 password and output the password to the standard output. If the
240 \&\f(CW\*(C`SUDO_ASKPASS\*(C'\fR environment variable is set, it specifies the path
241 to the helper program. Otherwise, if \fI@sysconfdir@/sudo.conf\fR
242 contains a line specifying the askpass program, that value will be
246 \& # Path to askpass helper program
247 \& Path askpass /usr/X11R6/bin/ssh\-askpass
250 If no askpass program is available, sudo will exit with an error.
252 .IP "\-a \fItype\fR" 12
254 The \fB\-a\fR (\fIauthentication type\fR) option causes \fBsudo\fR to use the
255 specified authentication type when validating the user, as allowed
256 by \fI/etc/login.conf\fR. The system administrator may specify a list
257 of sudo-specific authentication methods by adding an \*(L"auth-sudo\*(R"
258 entry in \fI/etc/login.conf\fR. This option is only available on systems
259 that support \s-1BSD\s0 authentication.
263 The \fB\-b\fR (\fIbackground\fR) option tells \fBsudo\fR to run the given
264 command in the background. Note that if you use the \fB\-b\fR
265 option you cannot use shell job control to manipulate the process.
266 Most interactive commands will fail to work properly in background
268 .IP "\-C \fIfd\fR" 12
270 Normally, \fBsudo\fR will close all open file descriptors other than
271 standard input, standard output and standard error. The \fB\-C\fR
272 (\fIclose from\fR) option allows the user to specify a starting point
273 above the standard error (file descriptor three). Values less than
274 three are not permitted. The security policy may restrict the
275 user's ability to use the \fB\-C\fR option. The \fIsudoers\fR policy only
276 permits use of the \fB\-C\fR option when the administrator has enabled
277 the \fIclosefrom_override\fR option.
279 .IP "\-c \fIclass\fR" 12
281 The \fB\-c\fR (\fIclass\fR) option causes \fBsudo\fR to run the specified command
282 with resources limited by the specified login class. The \fIclass\fR
283 argument can be either a class name as defined in \fI/etc/login.conf\fR,
284 or a single '\-' character. Specifying a \fIclass\fR of \f(CW\*(C`\-\*(C'\fR indicates
285 that the command should be run restricted by the default login
286 capabilities for the user the command is run as. If the \fIclass\fR
287 argument specifies an existing user class, the command must be run
288 as root, or the \fBsudo\fR command must be run from a shell that is already
289 root. This option is only available on systems with \s-1BSD\s0 login classes.
291 .IP "\-D \fIlevel\fR" 12
293 Enable debugging of \fBsudo\fR plugins and \fBsudo\fR itself. The \fIlevel\fR
294 may be a value from 1 through 9.
297 The \fB\-E\fR (\fIpreserve\fR \fIenvironment\fR) option indicates to the
298 security policy that the uses wishes to preserve their existing
299 environment variables. The security policy may return an error if
300 the \fB\-E\fR option is specified and the user does not have permission
301 to preserve the environment.
304 The \fB\-e\fR (\fIedit\fR) option indicates that, instead of running a
305 command, the user wishes to edit one or more files. In lieu of a
306 command, the string \*(L"sudoedit\*(R" is used when consulting the security
307 policy. If the user is authorized by the policy, the following
311 Temporary copies are made of the files to be edited with the owner
312 set to the invoking user.
314 The editor specified by the policy is run to edit the temporary files.
315 The \fIsudoers\fR policy uses the \f(CW\*(C`SUDO_EDITOR\*(C'\fR, \f(CW\*(C`VISUAL\*(C'\fR and \f(CW\*(C`EDITOR\*(C'\fR
316 environment variables (in that order). If none of \f(CW\*(C`SUDO_EDITOR\*(C'\fR,
317 \&\f(CW\*(C`VISUAL\*(C'\fR or \f(CW\*(C`EDITOR\*(C'\fR are set, the first program listed in the
318 \&\fIeditor\fR \fIsudoers\fR\|(@mansectform@) option is used.
320 If they have been modified, the temporary files are copied back to
321 their original location and the temporary versions are removed.
325 If the specified file does not exist, it will be created. Note
326 that unlike most commands run by \fBsudo\fR, the editor is run with
327 the invoking user's environment unmodified. If, for some reason,
328 \&\fBsudo\fR is unable to update a file with its edited version, the
329 user will receive a warning and the edited copy will remain in a
332 .IP "\-g \fIgroup\fR" 12
334 Normally, \fBsudo\fR runs a command with the primary group set to the
335 one specified by the password database for the user the command is
336 being run as (by default, root). The \fB\-g\fR (\fIgroup\fR) option causes
337 \&\fBsudo\fR to run the command with the primary group set to \fIgroup\fR
338 instead. To specify a \fIgid\fR instead of a \fIgroup name\fR, use
339 \&\fI#gid\fR. When running commands as a \fIgid\fR, many shells require
340 that the '#' be escaped with a backslash ('\e'). If no \fB\-u\fR option
341 is specified, the command will be run as the invoking user (not
342 root). In either case, the primary group will be set to \fIgroup\fR.
345 The \fB\-H\fR (\fI\s-1HOME\s0\fR) option requests that the security policy set
346 the \f(CW\*(C`HOME\*(C'\fR environment variable to the home directory of the target
347 user (root by default) as specified by the password database.
348 Depending on the policy, this may be the default behavior.
351 The \fB\-h\fR (\fIhelp\fR) option causes \fBsudo\fR to print a short help message
352 to the standard output and exit.
353 .IP "\-i [command]" 12
354 .IX Item "-i [command]"
355 The \fB\-i\fR (\fIsimulate initial login\fR) option runs the shell specified
356 by the password database entry of the target user as a login shell.
357 This means that login-specific resource files such as \f(CW\*(C`.profile\*(C'\fR
358 or \f(CW\*(C`.login\*(C'\fR will be read by the shell. If a command is specified,
359 it is passed to the shell for execution via the shell's \fB\-c\fR option.
360 If no command is specified, an interactive shell is executed.
361 \&\fBsudo\fR attempts to change to that user's home directory before
362 running the shell. The security policy shall initialize the
363 environment to a minimal set of variables, similar to what is present
367 The \fB\-K\fR (sure \fIkill\fR) option is like \fB\-k\fR except that it removes
368 the user's cached credentials entirely and may not be used in
369 conjunction with a command or other option. This option does not
370 require a password. Not all security policies support credential
372 .IP "\-k [command]" 12
373 .IX Item "-k [command]"
374 When used alone, the \fB\-k\fR (\fIkill\fR) option to \fBsudo\fR invalidates
375 the user's cached credentials. The next time \fBsudo\fR is run a
376 password will be required. This option does not require a password
377 and was added to allow a user to revoke \fBsudo\fR permissions from a
378 \&.logout file. Not all security policies support credential
381 When used in conjunction with a command or an option that may require
382 a password, the \fB\-k\fR option will cause \fBsudo\fR to ignore the user's
383 cached credentials. As a result, \fBsudo\fR will prompt for a password
384 (if one is required by the security policy) and will not update the
385 user's cached credentials.
386 .IP "\-l[l] [\fIcommand\fR]" 12
387 .IX Item "-l[l] [command]"
388 If no \fIcommand\fR is specified, the \fB\-l\fR (\fIlist\fR) option will list
389 the allowed (and forbidden) commands for the invoking user (or the
390 user specified by the \fB\-U\fR option) on the current host. If a
391 \&\fIcommand\fR is specified and is permitted by the security policy,
392 the fully-qualified path to the command is displayed along with any
393 command line arguments. If \fIcommand\fR is specified but not allowed,
394 \&\fBsudo\fR will exit with a status value of 1. If the \fB\-l\fR option
395 is specified with an \fBl\fR argument (i.e. \fB\-ll\fR), or if \fB\-l\fR is
396 specified multiple times, a longer list format is used.
399 The \fB\-n\fR (\fInon-interactive\fR) option prevents \fBsudo\fR from prompting
400 the user for a password. If a password is required for the command
401 to run, \fBsudo\fR will display an error messages and exit.
404 The \fB\-P\fR (\fIpreserve\fR \fIgroup vector\fR) option causes \fBsudo\fR to
405 preserve the invoking user's group vector unaltered. By default,
406 the \fIsudoers\fR policy will initialize the group vector to the list
407 of groups the target user is in. The real and effective group IDs,
408 however, are still set to match the target user.
409 .IP "\-p \fIprompt\fR" 12
411 The \fB\-p\fR (\fIprompt\fR) option allows you to override the default
412 password prompt and use a custom one. The following percent (`\f(CW\*(C`%\*(C'\fR')
413 escapes are supported by the \fIsudoers\fR policy:
416 .el .IP "\f(CW%H\fR" 4
418 expanded to the host name including the domain name (on if
419 the machine's host name is fully qualified or the \fIfqdn\fR option
420 is set in \fIsudoers\fR\|(@mansectform@))
422 .el .IP "\f(CW%h\fR" 4
424 expanded to the local host name without the domain name
426 .el .IP "\f(CW%p\fR" 4
428 expanded to the name of the user whose password is being requested
429 (respects the \fIrootpw\fR, \fItargetpw\fR and \fIrunaspw\fR flags in
430 \&\fIsudoers\fR\|(@mansectform@))
432 .el .IP "\f(CW%U\fR" 4
434 expanded to the login name of the user the command will be run as
435 (defaults to root unless the \f(CW\*(C`\-u\*(C'\fR option is also specified)
437 .el .IP "\f(CW%u\fR" 4
439 expanded to the invoking user's login name
440 .ie n .IP "\*(C`%%\*(C'" 4
441 .el .IP "\f(CW\*(C`%%\*(C'\fR" 4
443 two consecutive \f(CW\*(C`%\*(C'\fR characters are collapsed into a single \f(CW\*(C`%\*(C'\fR character
447 The prompt specified by the \fB\-p\fR option will override the system
448 password prompt on systems that support \s-1PAM\s0 unless the
449 \&\fIpassprompt_override\fR flag is disabled in \fIsudoers\fR.
452 .IP "\-r \fIrole\fR" 12
454 The \fB\-r\fR (\fIrole\fR) option causes the new (SELinux) security context to
455 have the role specified by \fIrole\fR.
459 The \fB\-S\fR (\fIstdin\fR) option causes \fBsudo\fR to read the password from
460 the standard input instead of the terminal device. The password must
461 be followed by a newline character.
462 .IP "\-s [command]" 12
463 .IX Item "-s [command]"
464 The \fB\-s\fR (\fIshell\fR) option runs the shell specified by the \fI\s-1SHELL\s0\fR
465 environment variable if it is set or the shell as specified in the
466 password database. If a command is specified, it is passed to the
467 shell for execution via the shell's \fB\-c\fR option. If no command
468 is specified, an interactive shell is executed.
470 .IP "\-t \fItype\fR" 12
472 The \fB\-t\fR (\fItype\fR) option causes the new (SELinux) security context to
473 have the type specified by \fItype\fR. If no type is specified, the default
474 type is derived from the specified role.
476 .IP "\-U \fIuser\fR" 12
478 The \fB\-U\fR (\fIother user\fR) option is used in conjunction with the
479 \&\fB\-l\fR option to specify the user whose privileges should be listed.
480 The security policy may restrict listing other users' privileges.
481 The \fIsudoers\fR policy only allows root or a user with the \f(CW\*(C`ALL\*(C'\fR
482 privilege on the current host to use this option.
483 .IP "\-u \fIuser\fR" 12
485 The \fB\-u\fR (\fIuser\fR) option causes \fBsudo\fR to run the specified
486 command as a user other than \fIroot\fR. To specify a \fIuid\fR instead
487 of a \fIuser name\fR, use \fI#uid\fR. When running commands as a \fIuid\fR,
488 many shells require that the '#' be escaped with a backslash ('\e').
489 Security policies may restrict \fIuid\fRs to those listed in the
490 password database. The \fIsudoers\fR policy allows \fIuid\fRs that are
491 not in the password database as long as the \fItargetpw\fR option is
492 not set. Other security policies may not support this.
495 The \fB\-V\fR (\fIversion\fR) option causes \fBsudo\fR to print its version
496 string and the version string of the security policy plugin and any
497 I/O plugins. If the invoking user is already root the \fB\-V\fR option
498 will display the arguments passed to configure when \fIsudo\fR was
499 built and plugins may display more verbose information such as
503 When given the \fB\-v\fR (\fIvalidate\fR) option, \fBsudo\fR will update the
504 user's cached credentials, authenticating the user's password if
505 necessary. For the \fIsudoers\fR plugin, this extends the \fBsudo\fR
506 timeout for another \f(CW\*(C`@timeout@\*(C'\fR minutes (or whatever the timeout
507 is set to in \fIsudoers\fR) but does not run a command. Not all
508 security policies support cached credentials.
510 The \fB\-\-\fR option indicates that \fBsudo\fR should stop processing command
513 Environment variables to be set for the command may also be passed
514 on the command line in the form of \fB\s-1VAR\s0\fR=\fIvalue\fR, e.g.
515 \&\fB\s-1LD_LIBRARY_PATH\s0\fR=\fI/usr/local/pkg/lib\fR. Variables passed on the
516 command line are subject to the same restrictions as normal environment
517 variables with one important exception. If the \fIsetenv\fR option
518 is set in \fIsudoers\fR, the command to be run has the \f(CW\*(C`SETENV\*(C'\fR tag
519 set or the command matched is \f(CW\*(C`ALL\*(C'\fR, the user may set variables
520 that would overwise be forbidden. See \fIsudoers\fR\|(@mansectform@) for more information.
523 Plugins are dynamically loaded based on the contents of the
524 \&\fI@sysconfdir@/sudo.conf\fR file. If no \fI@sysconfdir@/sudo.conf\fR
525 file is present, or it contains no \f(CW\*(C`Plugin\*(C'\fR lines, \fBsudo\fR
526 will use the traditional \fIsudoers\fR security policy and I/O logging,
527 which corresponds to the following \fI@sysconfdir@/sudo.conf\fR file.
531 \& # Default @sysconfdir@/sudo.conf file
534 \& # Plugin plugin_name plugin_path
535 \& # Path askpass /path/to/askpass
536 \& # Path noexec /path/to/noexec.so
538 \& # The plugin_path is relative to @prefix@/libexec unless
539 \& # fully qualified.
540 \& # The plugin_name corresponds to a global symbol in the plugin
541 \& # that contains the plugin interface structure.
543 \& Plugin policy_plugin sudoers.so
544 \& Plugin io_plugin sudoers.so
547 A \f(CW\*(C`Plugin\*(C'\fR line consists of the \f(CW\*(C`Plugin\*(C'\fR keyword, followed by the
548 \&\fIsymbol_name\fR and the \fIpath\fR to the shared object containing the
549 plugin. The \fIsymbol_name\fR is the name of the \f(CW\*(C`struct policy_plugin\*(C'\fR
550 or \f(CW\*(C`struct io_plugin\*(C'\fR in the plugin shared object. The \fIpath\fR
551 may be fully qualified or relative. If not fully qualified it is
552 relative to the \fI@prefix@/libexec\fR directory. Any additional
553 parameters after the \fIpath\fR are ignored. Lines that don't begin
554 with \f(CW\*(C`Plugin\*(C'\fR or \f(CW\*(C`Path\*(C'\fR are silently ignored
556 For more information, see the \fIsudo_plugin\fR\|(@mansectsu@) manual.
559 A \f(CW\*(C`Path\*(C'\fR line consists of the \f(CW\*(C`Path\*(C'\fR keyword, followed by the
560 name of the path to set and its value. E.g.
563 \& Path noexec @noexec_file@
564 \& Path askpass /usr/X11R6/bin/ssh\-askpass
567 The following plugin-agnostic paths may be set in the
568 \&\fI@sysconfdir@/sudo.conf\fR file.
571 The fully qualified path to a helper program used to read the user's
572 password when no terminal is available. This may be the case when
573 \&\fBsudo\fR is executed from a graphical (as opposed to text-based)
574 application. The program specified by \fIaskpass\fR should display
575 the argument passed to it as the prompt and write the user's password
576 to the standard output. The value of \fIaskpass\fR may be overridden
577 by the \f(CW\*(C`SUDO_ASKPASS\*(C'\fR environment variable.
580 The fully-qualified path to a shared library containing dummy
581 versions of the \fIexecv()\fR, \fIexecve()\fR and \fIfexecve()\fR library functions
582 that just return an error. This is used to implement the \fInoexec\fR
583 functionality on systems that support \f(CW\*(C`LD_PRELOAD\*(C'\fR or its equivalent.
584 Defaults to \fI@noexec_file@\fR.
586 .IX Header "RETURN VALUES"
587 Upon successful execution of a program, the exit status from \fBsudo\fR
588 will simply be the exit status of the program that was executed.
590 Otherwise, \fBsudo\fR exits with a value of 1 if there is a
591 configuration/permission problem or if \fBsudo\fR cannot execute the
592 given command. In the latter case the error string is printed to
593 the standard error. If \fBsudo\fR cannot \fIstat\fR\|(2) one or more entries
594 in the user's \f(CW\*(C`PATH\*(C'\fR, an error is printed on stderr. (If the
595 directory does not exist or if it is not really a directory, the
596 entry is ignored and no error is printed.) This should not happen
597 under normal circumstances. The most common reason for \fIstat\fR\|(2)
598 to return \*(L"permission denied\*(R" is if you are running an automounter
599 and one of the directories in your \f(CW\*(C`PATH\*(C'\fR is on a machine that is
600 currently unreachable.
602 .IX Header "SECURITY NOTES"
603 \&\fBsudo\fR tries to be safe when executing external commands.
605 To prevent command spoofing, \fBsudo\fR checks \*(L".\*(R" and "" (both denoting
606 current directory) last when searching for a command in the user's
607 \&\s-1PATH\s0 (if one or both are in the \s-1PATH\s0). Note, however, that the
608 actual \f(CW\*(C`PATH\*(C'\fR environment variable is \fInot\fR modified and is passed
609 unchanged to the program that \fBsudo\fR executes.
611 Please note that \fBsudo\fR will normally only log the command it
612 explicitly runs. If a user runs a command such as \f(CW\*(C`sudo su\*(C'\fR or
613 \&\f(CW\*(C`sudo sh\*(C'\fR, subsequent commands run from that shell are not subject
614 to \fBsudo\fR's security policy. The same is true for commands that
615 offer shell escapes (including most editors). If I/O logging is
616 enabled, subsequent commands will have their input and/or output
617 logged, but there will not be traditional logs for those commands.
618 Because of this, care must be taken when giving users access to
619 commands via \fBsudo\fR to verify that the command does not inadvertently
620 give the user an effective root shell. For more information, please
621 see the \f(CW\*(C`PREVENTING SHELL ESCAPES\*(C'\fR section in \fIsudoers\fR\|(@mansectform@).
623 .IX Header "ENVIRONMENT"
624 \&\fBsudo\fR utilizes the following environment variables. The security
625 policy has control over the content of the command's environment.
626 .ie n .IP "\*(C`EDITOR\*(C'" 16
627 .el .IP "\f(CW\*(C`EDITOR\*(C'\fR" 16
629 Default editor to use in \fB\-e\fR (sudoedit) mode if neither \f(CW\*(C`SUDO_EDITOR\*(C'\fR
630 nor \f(CW\*(C`VISUAL\*(C'\fR is set
631 .ie n .IP "\*(C`MAIL\*(C'" 16
632 .el .IP "\f(CW\*(C`MAIL\*(C'\fR" 16
634 In \fB\-i\fR mode or when \fIenv_reset\fR is enabled in \fIsudoers\fR, set
635 to the mail spool of the target user
636 .ie n .IP "\*(C`HOME\*(C'" 16
637 .el .IP "\f(CW\*(C`HOME\*(C'\fR" 16
639 Set to the home directory of the target user if \fB\-i\fR or \fB\-H\fR are
640 specified, \fIenv_reset\fR or \fIalways_set_home\fR are set in \fIsudoers\fR,
641 or when the \fB\-s\fR option is specified and \fIset_home\fR is set in
643 .ie n .IP "\*(C`PATH\*(C'" 16
644 .el .IP "\f(CW\*(C`PATH\*(C'\fR" 16
646 May be overridden by the security policy.
647 .ie n .IP "\*(C`SHELL\*(C'" 16
648 .el .IP "\f(CW\*(C`SHELL\*(C'\fR" 16
650 Used to determine shell to run with \f(CW\*(C`\-s\*(C'\fR option
651 .ie n .IP "\*(C`SUDO_ASKPASS\*(C'" 16
652 .el .IP "\f(CW\*(C`SUDO_ASKPASS\*(C'\fR" 16
653 .IX Item "SUDO_ASKPASS"
654 Specifies the path to a helper program used to read the password
655 if no terminal is available or if the \f(CW\*(C`\-A\*(C'\fR option is specified.
656 .ie n .IP "\*(C`SUDO_COMMAND\*(C'" 16
657 .el .IP "\f(CW\*(C`SUDO_COMMAND\*(C'\fR" 16
658 .IX Item "SUDO_COMMAND"
659 Set to the command run by sudo
660 .ie n .IP "\*(C`SUDO_EDITOR\*(C'" 16
661 .el .IP "\f(CW\*(C`SUDO_EDITOR\*(C'\fR" 16
662 .IX Item "SUDO_EDITOR"
663 Default editor to use in \fB\-e\fR (sudoedit) mode
664 .ie n .IP "\*(C`SUDO_GID\*(C'" 16
665 .el .IP "\f(CW\*(C`SUDO_GID\*(C'\fR" 16
667 Set to the group \s-1ID\s0 of the user who invoked sudo
668 .ie n .IP "\*(C`SUDO_PROMPT\*(C'" 16
669 .el .IP "\f(CW\*(C`SUDO_PROMPT\*(C'\fR" 16
670 .IX Item "SUDO_PROMPT"
671 Used as the default password prompt
672 .ie n .IP "\*(C`SUDO_PS1\*(C'" 16
673 .el .IP "\f(CW\*(C`SUDO_PS1\*(C'\fR" 16
675 If set, \f(CW\*(C`PS1\*(C'\fR will be set to its value for the program being run
676 .ie n .IP "\*(C`SUDO_UID\*(C'" 16
677 .el .IP "\f(CW\*(C`SUDO_UID\*(C'\fR" 16
679 Set to the user \s-1ID\s0 of the user who invoked sudo
680 .ie n .IP "\*(C`SUDO_USER\*(C'" 16
681 .el .IP "\f(CW\*(C`SUDO_USER\*(C'\fR" 16
683 Set to the login of the user who invoked sudo
684 .ie n .IP "\*(C`USER\*(C'" 16
685 .el .IP "\f(CW\*(C`USER\*(C'\fR" 16
687 Set to the target user (root unless the \fB\-u\fR option is specified)
688 .ie n .IP "\*(C`VISUAL\*(C'" 16
689 .el .IP "\f(CW\*(C`VISUAL\*(C'\fR" 16
691 Default editor to use in \fB\-e\fR (sudoedit) mode if \f(CW\*(C`SUDO_EDITOR\*(C'\fR
695 .ie n .IP "\fI@sysconfdir@/sudo.conf\fR" 24
696 .el .IP "\fI@sysconfdir@/sudo.conf\fR" 24
697 .IX Item "@sysconfdir@/sudo.conf"
698 \&\fBsudo\fR plugin and path configuration
700 .IX Header "EXAMPLES"
701 Note: the following examples assume a properly configured security policy.
703 To get a file listing of an unreadable directory:
706 \& $ sudo ls /usr/local/protected
709 To list the home directory of user yaz on a machine where the
710 file system holding ~yaz is not exported as root:
713 \& $ sudo \-u yaz ls ~yaz
716 To edit the \fIindex.html\fR file as user www:
719 \& $ sudo \-u www vi ~www/htdocs/index.html
722 To view system logs only accessible to root and users in the adm group:
725 \& $ sudo \-g adm view /var/log/syslog
728 To run an editor as jim with a different primary group:
731 \& $ sudo \-u jim \-g audio vi ~jim/sound.txt
734 To shutdown a machine:
737 \& $ sudo shutdown \-r +15 "quick reboot"
740 To make a usage listing of the directories in the /home
741 partition. Note that this runs the commands in a sub-shell
742 to make the \f(CW\*(C`cd\*(C'\fR and file redirection work.
745 \& $ sudo sh \-c "cd /home ; du \-s * | sort \-rn > USAGE"
748 .IX Header "SEE ALSO"
749 \&\fIgrep\fR\|(1), \fIsu\fR\|(1), \fIstat\fR\|(2),
750 .if \n(LC \&\fIlogin_cap\fR\|(3),
751 \&\fIpasswd\fR\|(@mansectform@), \fIsudoers\fR\|(@mansectform@), \fIsudo_plugin\fR\|(@mansectsu@), \fIsudoreplay\fR\|(@mansectsu@), \fIvisudo\fR\|(@mansectsu@)
754 Many people have worked on \fBsudo\fR over the years; this
755 version consists of code written primarily by:
761 See the \s-1HISTORY\s0 file in the \fBsudo\fR distribution or visit
762 http://www.sudo.ws/sudo/history.html for a short history
766 There is no easy way to prevent a user from gaining a root shell
767 if that user is allowed to run arbitrary commands via \fBsudo\fR.
768 Also, many programs (such as editors) allow the user to run commands
769 via shell escapes, thus avoiding \fBsudo\fR's checks. However, on
770 most systems it is possible to prevent shell escapes with the
771 \&\fIsudoers\fR\|(@mansectform@) module's \fInoexec\fR functionality.
773 It is not meaningful to run the \f(CW\*(C`cd\*(C'\fR command directly via sudo, e.g.,
776 \& $ sudo cd /usr/local/protected
779 since when the command exits the parent process (your shell) will
780 still be the same. Please see the \s-1EXAMPLES\s0 section for more information.
782 Running shell scripts via \fBsudo\fR can expose the same kernel bugs that
783 make setuid shell scripts unsafe on some operating systems (if your \s-1OS\s0
784 has a /dev/fd/ directory, setuid shell scripts are generally safe).
787 If you feel you have found a bug in \fBsudo\fR, please submit a bug report
788 at http://www.sudo.ws/sudo/bugs/
791 Limited free support is available via the sudo-users mailing list,
792 see http://www.sudo.ws/mailman/listinfo/sudo\-users to subscribe or
795 .IX Header "DISCLAIMER"
796 \&\fBsudo\fR is provided ``\s-1AS\s0 \s-1IS\s0'' and any express or implied warranties,
797 including, but not limited to, the implied warranties of merchantability
798 and fitness for a particular purpose are disclaimed. See the \s-1LICENSE\s0
799 file distributed with \fBsudo\fR or http://www.sudo.ws/sudo/license.html
800 for complete details.
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