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sudo.conf(5)                   File Formats Manual                  sudo.conf(5)


NAME

     sudo.conf - configuration for sudo front-end


DESCRIPTION

     The sudo.conf file is used to configure the sudo front-end.  It is used to
     configure sudo plugins, plugin-agnostic path names, debug flags, and other
     settings.

     The sudo.conf file supports the following directives, described in detail
     below.

     Plugin    an approval, audit, I/O logging, or security policy plugin

     Path      a plugin-agnostic path

     Set       a front-end setting, such as disable_coredump or group_source

     Debug     debug flags to aid in debugging sudo, sudoreplay, visudo, and the
               sudoers plugin.

     The pound sign (`#') is used to indicate a comment.  Both the comment
     character and any text after it, up to the end of the line, are ignored.

     Long lines can be continued with a backslash (`\') as the last character on
     the line.  Leading white space is removed from the beginning of lines even
     when a continuation character is used.

     Non-comment lines that don't begin with Plugin, Path, Debug, or Set are
     silently ignored.

     The sudo.conf file is always parsed in the "C" locale.

   Plugin configuration
     sudo supports a plugin architecture for security policies and input/output
     logging.  Third parties can develop and distribute their own policy and I/O
     logging plugins to work seamlessly with the sudo front-end.  Plugins are
     dynamically loaded based on the contents of sudo.conf.

     A Plugin line consists of the Plugin keyword, followed by the symbol_name
     and the path to the dynamic shared object that contains the plugin.  The
     symbol_name is the name of the approval_plugin, audit_plugin, io_plugin, or
     policy_plugin struct contained in the plugin.  If a plugin implements
     multiple plugin types, there must be a Plugin line for each unique symbol
     name.  The path may be fully qualified or relative.  If not fully
     qualified, it is relative to the directory specified by the plugin_dir Path
     setting, which defaults to /opt/local/libexec/sudo.  In other words:

         Plugin sudoers_policy sudoers.so

     is equivalent to:

         Plugin sudoers_policy /opt/local/libexec/sudo/sudoers.so

     If the plugin was compiled statically into the sudo binary instead of being
     installed as a dynamic shared object, the path should be specified without
     a leading directory, as it does not actually exist in the file system.  For
     example:

         Plugin sudoers_policy sudoers.so

     Starting with sudo 1.8.5, any additional parameters after the path are
     passed as arguments to the plugin's open function.  For example, to
     override the compile-time default sudoers file mode:

         Plugin sudoers_policy sudoers.so sudoers_mode=0440

     See the sudoers(5) manual for a list of supported arguments.

     The same dynamic shared object may contain multiple plugins, each with a
     different symbol name.  The file must be owned by user-ID 0 and only
     writable by its owner.  Because of ambiguities that arise from composite
     policies, only a single policy plugin may be specified.  This limitation
     does not apply to I/O plugins.

     If no sudo.conf file is present, or if it contains no Plugin lines, the
     sudoers plugin will be used as the default security policy, for I/O logging
     (if enabled by the policy), and for auditing.  This is equivalent to the
     following:

         Plugin sudoers_policy sudoers.so
         Plugin sudoers_io sudoers.so
         Plugin sudoers_audit sudoers.so

     Starting with sudo version 1.9.1, some of the logging functionality of the
     sudoers plugin has been moved from the policy plugin to an audit plugin.
     To maintain compatibility with sudo.conf files from older sudo versions, if
     sudoers is configured as the security policy, it will be used as an audit
     plugin as well.  This guarantees that the logging behavior will be
     consistnet with that of sudo versions 1.9.0 and below.

     For more information on the sudo plugin architecture, see the
     sudo_plugin(5) manual.

   Path settings
     A Path line consists of the Path keyword, followed by the name of the path
     to set and its value.  For example:

         Path intercept /opt/local/libexec/sudo/sudo_intercept.so
         Path noexec /opt/local/libexec/sudo/sudo_noexec.so
         Path askpass /usr/X11R6/bin/ssh-askpass

     If no path name is specified, features relying on the specified setting
     will be disabled.  Disabling Path settings is only supported in sudo
     version 1.8.16 and higher.

     The following plugin-agnostic paths may be set in the
     /opt/local/etc/sudo.conf file:

     askpass   The fully qualified path to a helper program used to read the
               user's password when no terminal is available.  This may be the
               case when sudo is executed from a graphical (as opposed to text-
               based) application.  The program specified by askpass should
               display the argument passed to it as the prompt and write the
               user's password to the standard output.  The value of askpass may
               be overridden by the SUDO_ASKPASS environment variable.

     devsearch
               An ordered, colon-separated search path of directories to look in
               for device nodes.  This is used when mapping the process's tty
               device number to a device name on systems that do not provide
               such a mechanism.  Sudo will not recurse into sub-directories.
               If terminal devices may be located in a sub-directory of /dev,
               that path must be explicitly listed in devsearch.  The default
               value is /dev/pts:/dev/vt:/dev/term:/dev/zcons:/dev/pty:/dev

               This option is ignored on systems that support either the
               devname() or _ttyname_dev() functions, for example BSD, macOS and
               Solaris.

     intercept
               The fully-qualified path to a shared library containing a
               wrappers for the execl(), execle(), execlp(), execv(), execve(),
               execvp(), execvpe(), and system() library functions that
               intercepts attempts to run further commands and performs a policy
               check before allowing them to be executed.  This is used to
               implement the intercept functionality on systems that support
               LD_PRELOAD or its equivalent.  The default value is
               /opt/local/libexec/sudo/sudo_intercept.so.

     noexec    The fully-qualified path to a shared library containing wrappers
               for the execl(), execle(), execlp(), exect(), execv(), execve(),
               execveat(), execvP(), execvp(), execvpe(), fexecve(), popen(),
               posix_spawn(), posix_spawnp(), system(), and wordexp() library
               functions that prevent the execution of further commands.  This
               is used to implement the noexec functionality on systems that
               support LD_PRELOAD or its equivalent.  The default value is
               /opt/local/libexec/sudo/sudo_noexec.so.

     plugin_dir
               The default directory to use when searching for plugins that are
               specified without a fully qualified path name.  The default value
               is /opt/local/libexec/sudo.

   Other settings
     The sudo.conf file also supports the following front-end settings:

     disable_coredump
               Core dumps of sudo itself are disabled by default to prevent the
               disclosure of potentially sensitive information.  To aid in
               debugging sudo crashes, you may wish to re-enable core dumps by
               setting "disable_coredump" to false in sudo.conf as follows:

                   Set disable_coredump false

               All modern operating systems place restrictions on core dumps
               from set-user-ID processes like sudo so this option can be
               enabled without compromising security.  To actually get a sudo
               core file you will likely need to enable core dumps for set-user-
               ID processes.  On BSD and Linux systems this is accomplished in
               the sysctl(8) command.  On Solaris, the coreadm(1m) command is
               used to configure core dump behavior.

               This setting is only available in sudo version 1.8.4 and higher.

     developer_mode
               By default sudo refuses to load plugins which can be modified by
               other than the root user.  The plugin should be owned by root and
               write access permissions should be disabled for "group" and
               "other".  To make development of a plugin easier, you can disable
               that by setting "developer_mode" option to true in sudo.conf as
               follows:

                   Set developer_mode true

               This creates a security risk and is not recommended for
               production systems, it is intended to be used in a development
               environment (VM, container, etc).  Before enabling developer
               mode, be sure that you understand the implications.

               This setting is only available in sudo version 1.9.0 and higher.

     group_source
               sudo passes the invoking user's group list to the policy and I/O
               plugins.  On most systems, there is an upper limit to the number
               of groups that a user may belong to simultaneously (typically 16
               for compatibility with NFS).  On systems with the getconf(1)
               utility, running:
                     getconf NGROUPS_MAX
               will return the maximum number of groups.

               However, it is still possible to be a member of a larger number
               of groups--they simply won't be included in the group list
               returned by the kernel for the user.  Starting with sudo version
               1.8.7, if the user's kernel group list has the maximum number of
               entries, sudo will consult the group database directly to
               determine the group list.  This makes it possible for the
               security policy to perform matching by group name even when the
               user is a member of more than the maximum number of groups.

               The group_source setting allows the administrator to change this
               default behavior.  Supported values for group_source are:

               static    Use the static group list that the kernel returns.
                         Retrieving the group list this way is very fast but it
                         is subject to an upper limit as described above.  It is
                         "static" in that it does not reflect changes to the
                         group database made after the user logs in.  This was
                         the default behavior prior to sudo 1.8.7.

               dynamic   Always query the group database directly.  It is
                         "dynamic" in that changes made to the group database
                         after the user logs in will be reflected in the group
                         list.  On some systems, querying the group database for
                         all of a user's groups can be time consuming when
                         querying a network-based group database.  Most
                         operating systems provide an efficient method of
                         performing such queries.  Currently, sudo supports
                         efficient group queries on AIX, BSD, HP-UX, Linux,
                         macOS, and Solaris.  This is the default behavior on
                         macOS in sudo 1.9.6 and higher.

               adaptive  Only query the group database if the static group list
                         returned by the kernel has the maximum number of
                         entries.  This is the default behavior on systems other
                         than macOS in sudo 1.8.7 and higher.

               For example, to cause sudo to only use the kernel's static list
               of groups for the user:

                   Set group_source static

               This setting is only available in sudo version 1.8.7 and higher.

     max_groups
               The maximum number of user groups to retrieve from the group
               database.  Values less than one or larger than 1024 will be
               ignored.  This setting is only used when querying the group
               database directly.  It is intended to be used on systems where it
               is not possible to detect when the array to be populated with
               group entries is not sufficiently large.  By default, sudo will
               allocate four times the system's maximum number of groups (see
               above) and retry with double that number if the group database
               query fails.

               This setting is only available in sudo version 1.8.7 and higher.
               It should not be required in sudo versions 1.8.24 and higher and
               may be removed in a later release.

     probe_interfaces
               By default, sudo will probe the system's network interfaces and
               pass the IP address of each enabled interface to the policy
               plugin.  This makes it possible for the plugin to match rules
               based on the IP address without having to query DNS.  On Linux
               systems with a large number of virtual interfaces, this may take
               a non-negligible amount of time.  If IP-based matching is not
               required, network interface probing can be disabled as follows:

                   Set probe_interfaces false

               This setting is only available in sudo version 1.8.10 and higher.

   Debug settings
     sudo versions 1.8.4 and higher support a flexible debugging framework that
     can log what sudo is doing internally if there is a problem.

     A Debug line consists of the Debug keyword, followed by the name of the
     program, plugin, or shared object to debug, the debug file name, and a
     comma-separated list of debug flags.  The debug flag syntax used by sudo,
     the sudoers plugin along with its associated programs and shared objects is
     subsystem@priority but a third-party plugin is free to use a different
     format so long as it does not include a comma (`,').

     Examples:

         Debug sudo /var/log/sudo_debug all@warn,plugin@info

     would log all debugging statements at the warn level and higher in addition
     to those at the info level for the plugin subsystem.

         Debug sudo_intercept.so /var/log/intercept_debug all@debug

     would log all debugging statements, regardless of level, for the
     sudo_intercept.so shared library that implements sudo's intercept
     functionality on some systems.

     As of sudo 1.8.12, multiple Debug entries may be specified per program.
     Older versions of sudo only support a single Debug entry per program.
     Plugin-specific Debug entries are also supported starting with sudo 1.8.12
     and are matched by either the base name of the plugin that was loaded (for
     example sudoers.so) or by the plugin's fully-qualified path name.
     Previously, the sudoers plugin shared the same Debug entry as the sudo
     front-end and could not be configured separately.

     The following priorities are supported, in order of decreasing severity:
     crit, err, warn, notice, diag, info, trace, and debug.  Each priority, when
     specified, also includes all priorities higher than it.  For example, a
     priority of notice would include debug messages logged at notice and
     higher.

     The priorities trace and debug also include function call tracing which
     logs when a function is entered and when it returns.  For example, the
     following trace is for the get_user_groups() function located in
     src/sudo.c:

         sudo[123] -> get_user_groups @ src/sudo.c:385
         sudo[123] <- get_user_groups @ src/sudo.c:429 := groups=10,0,5

     When the function is entered, indicated by a right arrow `->', the program,
     process ID, function, source file, and line number are logged.  When the
     function returns, indicated by a left arrow `<-', the same information is
     logged along with the return value.  In this case, the return value is a
     string.

     The following subsystems are used by the sudo front-end:

     all         matches every subsystem

     args        command line argument processing

     conv        user conversation

     edit        sudoedit

     event       event subsystem

     exec        command execution

     main        sudo main function

     netif       network interface handling

     pcomm       communication with the plugin

     plugin      plugin configuration

     pty         pseudo-terminal related code

     selinux     SELinux-specific handling

     util        utility functions

     utmp        utmp handling

     The sudoers(5) plugin includes support for additional subsystems.


FILES

     /opt/local/etc/sudo.conf  sudo front-end configuration


EXAMPLES

     #
     # Default /opt/local/etc/sudo.conf file
     #
     # Sudo plugins:
     #   Plugin plugin_name plugin_path plugin_options ...
     #
     # The plugin_path is relative to /opt/local/libexec/sudo unless
     #   fully qualified.
     # The plugin_name corresponds to a global symbol in the plugin
     #   that contains the plugin interface structure.
     # The plugin_options are optional.
     #
     # The sudoers plugin is used by default if no Plugin lines are present.
     #Plugin sudoers_policy sudoers.so
     #Plugin sudoers_io sudoers.so
     #Plugin sudoers_audit sudoers.so

     #
     # Sudo askpass:
     #   Path askpass /path/to/askpass
     #
     # An askpass helper program may be specified to provide a graphical
     # password prompt for "sudo -A" support.  Sudo does not ship with its
     # own askpass program but can use the OpenSSH askpass.
     #
     # Use the OpenSSH askpass
     #Path askpass /usr/X11R6/bin/ssh-askpass
     #
     # Use the Gnome OpenSSH askpass
     #Path askpass /usr/libexec/openssh/gnome-ssh-askpass

     #
     # Sudo device search path:
     #   Path devsearch /dev/path1:/dev/path2:/dev
     #
     # A colon-separated list of paths to check when searching for a user's
     # terminal device.
     #
     #Path devsearch /dev/pts:/dev/vt:/dev/term:/dev/zcons:/dev/pty:/dev

     #
     # Sudo command interception:
     #   Path intercept /path/to/sudo_intercept.so
     #
     # Path to a shared library containing replacements for the execv()
     # and execve() library functions that perform a policy check to verify
     # the command is allowed and simply return an error if not.  This is
     # used to implement the "intercept" functionality on systems that
     # support LD_PRELOAD or its equivalent.
     #
     # The compiled-in value is usually sufficient and should only be changed
     # if you rename or move the sudo_intercept.so file.
     #
     #Path intercept /opt/local/libexec/sudo/sudo_intercept.so

     #
     # Sudo noexec:
     #   Path noexec /path/to/sudo_noexec.so
     #
     # Path to a shared library containing replacements for the execv()
     # family of library functions that just return an error.  This is
     # used to implement the "noexec" functionality on systems that support
     # LD_PRELOAD or its equivalent.
     #
     # The compiled-in value is usually sufficient and should only be changed
     # if you rename or move the sudo_noexec.so file.
     #
     #Path noexec /opt/local/libexec/sudo/sudo_noexec.so

     #
     # Sudo plugin directory:
     #   Path plugin_dir /path/to/plugins
     #
     # The default directory to use when searching for plugins that are
     # specified without a fully qualified path name.
     #
     #Path plugin_dir /opt/local/libexec/sudo

     #
     # Sudo developer mode:
     #   Set developer_mode true|false
     #
     # Allow loading of plugins that are owned by non-root or are writable
     # by "group" or "other".  Should only be used during plugin development.
     #Set developer_mode true

     #
     # Core dumps:
     #   Set disable_coredump true|false
     #
     # By default, sudo disables core dumps while it is executing (they
     # are re-enabled for the command that is run).
     # To aid in debugging sudo problems, you may wish to enable core
     # dumps by setting "disable_coredump" to false.
     #
     #Set disable_coredump false

     #
     # User groups:
     #   Set group_source static|dynamic|adaptive
     #
     # Sudo passes the user's group list to the policy plugin.
     # If the user is a member of the maximum number of groups (usually 16),
     # sudo will query the group database directly to be sure to include
     # the full list of groups.
     #
     # On some systems, this can be expensive so the behavior is configurable.
     # The "group_source" setting has three possible values:
     #   static   - use the user's list of groups returned by the kernel.
     #   dynamic  - query the group database to find the list of groups.
     #   adaptive - if user is in less than the maximum number of groups.
     #              use the kernel list, else query the group database.
     #
     #Set group_source static

     #
     # Sudo interface probing:
     #   Set probe_interfaces true|false
     #
     # By default, sudo will probe the system's network interfaces and
     # pass the IP address of each enabled interface to the policy plugin.
     # On systems with a large number of virtual interfaces this may take
     # a noticeable amount of time.
     #
     #Set probe_interfaces false

     #
     # Sudo debug files:
     #   Debug program /path/to/debug_log subsystem@priority[,subsyste@priority]
     #
     # Sudo and related programs support logging debug information to a file.
     # The program is typically sudo, sudoers.so, sudoreplay, or visudo.
     #
     # Subsystems vary based on the program; "all" matches all subsystems.
     # Priority may be crit, err, warn, notice, diag, info, trace, or debug.
     # Multiple subsystem@priority may be specified, separated by a comma.
     #
     #Debug sudo /var/log/sudo_debug all@debug
     #Debug sudoers.so /var/log/sudoers_debug all@debug


SEE ALSO

     sudo_plugin(5), sudoers(5), sudo(8)


AUTHORS

     Many people have worked on sudo over the years; this version consists of
     code written primarily by:

           Todd C. Miller

     See the CONTRIBUTORS.md file in the sudo distribution
     (https://www.sudo.ws/about/contributors/) for an exhaustive list of people
     who have contributed to sudo.


BUGS

     If you believe you have found a bug in sudo, you can submit a bug report at
     https://bugzilla.sudo.ws/


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.


DISCLAIMER

     sudo 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.md file
     distributed with sudo or https://www.sudo.ws/about/license/ for complete
     details.

Sudo 1.9.11                       May 31, 2022                       Sudo 1.9.11

sudo 1.9.11 - Generated Tue Jun 7 08:24:45 CDT 2022
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