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diff --git a/doc/sudo.conf.man.in b/doc/sudo.conf.man.in new file mode 100644 index 0000000..36a3c00 --- /dev/null +++ b/doc/sudo.conf.man.in @@ -0,0 +1,864 @@ +.\" Automatically generated from an mdoc input file. Do not edit. +.\" +.\" SPDX-License-Identifier: ISC +.\" +.\" Copyright (c) 2010-2020 Todd C. Miller <Todd.Miller@sudo.ws> +.\" +.\" 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. +.\" +.nr SL @SEMAN@ +.TH "SUDO.CONF" "@mansectform@" "December 5, 2020" "Sudo @PACKAGE_VERSION@" "File Formats Manual" +.nh +.if n .ad l +.SH "NAME" +\fBsudo.conf\fR +\- configuration for sudo front end +.SH "DESCRIPTION" +The +\fBsudo.conf\fR +file is used to configure the +\fBsudo\fR +front end. +It specifies the security policy and I/O logging plugins, debug flags +as well as plugin-agnostic path names and settings. +.PP +The +\fBsudo.conf\fR +file supports the following directives, described in detail below. +.TP 10n +Plugin +a security policy or I/O logging plugin +.TP 10n +Path +a plugin-agnostic path +.TP 10n +Set +a front end setting, such as +\fIdisable_coredump\fR +or +\fIgroup_source\fR +.TP 10n +Debug +debug flags to aid in debugging +\fBsudo\fR, +\fBsudoreplay\fR, +\fBvisudo\fR, +and the +\fBsudoers\fR +plugin. +.PP +The pound sign +(\(oq#\(cq) +is used to indicate a comment. +Both the comment character and any text after it, up to the end of +the line, are ignored. +.PP +Long lines can be continued with a backslash +(\(oq\e\(cq) +as the last character on the line. +Note that leading white space is removed from the beginning of lines +even when the continuation character is used. +.PP +Non-comment lines that don't begin with +\fRPlugin\fR, +\fRPath\fR, +\fRDebug\fR, +or +\fRSet\fR +are silently ignored. +.PP +The +\fBsudo.conf\fR +file is always parsed in the +\(lq\fRC\fR\(rq +locale. +.SS "Plugin configuration" +\fBsudo\fR +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 +\fBsudo\fR +front end. +Plugins are dynamically loaded based on the contents of +\fBsudo.conf\fR. +.PP +A +\fRPlugin\fR +line consists of the +\fRPlugin\fR +keyword, followed by the +\fIsymbol_name\fR +and the +\fIpath\fR +to the dynamic shared object that contains the plugin. +The +\fIsymbol_name\fR +is the name of the +\fRapproval_plugin\fR, +\fRaudit_plugin\fR, +\fRio_plugin\fR, +or +\fRpolicy_plugin\fR +struct contained in the plugin. +If a plugin implements multiple plugin types, there must be a +\fRPlugin\fR +line for each unique symbol name. +The +\fIpath\fR +may be fully qualified or relative. +If not fully qualified, it is relative to the directory +specified by the +\fIplugin_dir\fR +\fRPath\fR +setting, which defaults to +\fI@plugindir@\fR. +In other words: +.nf +.sp +.RS 6n +Plugin sudoers_policy sudoers.so +.RE +.fi +.PP +is equivalent to: +.nf +.sp +.RS 6n +Plugin sudoers_policy @plugindir@/sudoers.so +.RE +.fi +.PP +If the plugin was compiled statically into the +\fBsudo\fR +binary instead of being installed as a dynamic shared object, the +\fIpath\fR +should be specified without a leading directory, +as it does not actually exist in the file system. +For example: +.nf +.sp +.RS 6n +Plugin sudoers_policy sudoers.so +.RE +.fi +.PP +Starting with +\fBsudo\fR +1.8.5, any additional parameters after the +\fIpath\fR +are passed as arguments to the plugin's +\fIopen\fR +function. +For example, to override the compile-time default sudoers file mode: +.nf +.sp +.RS 6n +Plugin sudoers_policy sudoers.so sudoers_mode=0440 +.RE +.fi +.PP +See the +sudoers(@mansectform@) +manual for a list of supported arguments. +.PP +The same dynamic shared object may contain multiple plugins, +each with a different symbol name. +The file must be owned by uid 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. +.PP +If no +\fBsudo.conf\fR +file is present, or if it contains no +\fRPlugin\fR +lines, the +\fBsudoers\fR +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: +.nf +.sp +.RS 6n +Plugin sudoers_policy sudoers.so +Plugin sudoers_io sudoers.so +Plugin sudoers_audit sudoers.so +.RE +.fi +.PP +Starting with +\fBsudo\fR +version 1.9.1, some of the logging functionality of the +\fBsudoers\fR +plugin has been moved from the policy plugin to an audit plugin. +To maintain compatibility with +\fBsudo.conf\fR +files from older +\fBsudo\fR +versions, if +\fBsudoers\fR +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 +\fBsudo\fR +versions 1.9.0 and below. +.PP +For more information on the +\fBsudo\fR +plugin architecture, see the +sudo_plugin(@mansectform@) +manual. +.SS "Path settings" +A +\fRPath\fR +line consists of the +\fRPath\fR +keyword, followed by the name of the path to set and its value. +For example: +.nf +.sp +.RS 6n +Path noexec @noexec_file@ +Path askpass /usr/X11R6/bin/ssh-askpass +.RE +.fi +.PP +If no path name is specified, features relying on the specified +setting will be disabled. +Disabling +\fRPath\fR +settings is only supported in +\fBsudo\fR +version 1.8.16 and higher. +.PP +The following plugin-agnostic paths may be set in the +\fI@sysconfdir@/sudo.conf\fR +file: +.TP 10n +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 +\fBsudo\fR +is executed from a graphical (as opposed to text-based) application. +The program specified by +\fIaskpass\fR +should display the argument passed to it as the prompt and write +the user's password to the standard output. +The value of +\fIaskpass\fR +may be overridden by the +\fRSUDO_ASKPASS\fR +environment variable. +.TP 10n +devsearch +.br +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 +\fInot\fR +recurse into sub-directories. +If terminal devices may be located in a sub-directory of +\fI/dev\fR, +that path must be explicitly listed in +\fIdevsearch\fR. +The default value is +\fR/dev/pts:/dev/vt:/dev/term:/dev/zcons:/dev/pty:/dev\fR +.sp +This option is ignored on systems that support either the +\fBdevname\fR() +or +\fB_ttyname_dev\fR() +functions, for example +BSD, +macOS and Solaris. +.TP 10n +noexec +The fully-qualified path to a shared library containing wrappers +for the +\fBexecl\fR(), +\fBexecle\fR(), +\fBexeclp\fR(), +\fBexect\fR(), +\fBexecv\fR(), +\fBexecve\fR(), +\fBexecvP\fR(), +\fBexecvp\fR(), +\fBexecvpe\fR(), +\fBfexecve\fR(), +\fBpopen\fR(), +\fBposix_spawn\fR(), +\fBposix_spawnp\fR(), +\fBsystem\fR(), +and +\fBwordexp\fR() +library functions that prevent the execution of further commands. +This is used to implement the +\fInoexec\fR +functionality on systems that support +\fRLD_PRELOAD\fR +or its equivalent. +The default value is +\fI@noexec_file@\fR. +.TP 10n +plugin_dir +The default directory to use when searching for plugins +that are specified without a fully qualified path name. +The default value is +\fI@plugindir@\fR. +.if \n(SL \{\ +.TP 10n +sesh +The fully-qualified path to the +\fBsesh\fR +binary. +This setting is only used when +\fBsudo\fR +is built with SELinux support. +The default value is +\fI@sesh_file@\fR. +.\} +.SS "Other settings" +The +\fBsudo.conf\fR +file also supports the following front end settings: +.TP 10n +disable_coredump +Core dumps of +\fBsudo\fR +itself are disabled by default to prevent the disclosure of potentially +sensitive information. +To aid in debugging +\fBsudo\fR +crashes, you may wish to re-enable core dumps by setting +\(lqdisable_coredump\(rq +to false in +\fBsudo.conf\fR +as follows: +.nf +.sp +.RS 16n +Set disable_coredump false +.RE +.fi +.RS 10n +.sp +All modern operating systems place restrictions on core dumps +from set-user-ID processes like +\fBsudo\fR +so this option can be enabled without compromising security. +To actually get a +\fBsudo\fR +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(@mansectsu@) +command. +On Solaris, the +coreadm(1m) +command is used to configure core dump behavior. +.sp +This setting is only available in +\fBsudo\fR +version 1.8.4 and higher. +.RE +.TP 10n +developer_mode +By default +\fBsudo\fR +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 +\(lqgroup\(rq +and +\(lqother\(rq\&. +To make development of a plugin easier, you can disable that by setting +\(lqdeveloper_mode\(rq +option to true in +\fBsudo.conf\fR +as follows: +.nf +.sp +.RS 16n +Set developer_mode true +.RE +.fi +.RS 10n +.sp +Please note that this creates a security risk, so it is not recommended +on critical systems such as a desktop machine for daily use, but is intended +to be used in development environments (VM, container, etc). +Before enabling developer mode, ensure you understand the implications. +.sp +This setting is only available in +\fBsudo\fR +version 1.9.0 and higher. +.RE +.TP 10n +group_source +\fBsudo\fR +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: +.RS 16n +getconf NGROUPS_MAX +.RE +.RS 10n +will return the maximum number of groups. +.sp +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 +\fBsudo\fR +version 1.8.7, if the user's kernel group list has the maximum number +of entries, +\fBsudo\fR +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. +.sp +The +\fIgroup_source\fR +setting allows the administrator to change this default behavior. +Supported values for +\fIgroup_source\fR +are: +.TP 10n +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 +\(lqstatic\(rq +in that it does not reflect changes to the group database made +after the user logs in. +This was the default behavior prior to +\fBsudo\fR +1.8.7. +.TP 10n +dynamic +Always query the group database directly. +It is +\(lqdynamic\(rq +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, +\fBsudo\fR +supports efficient group queries on AIX, +BSD, +HP-UX, Linux and Solaris. +.TP 10n +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 in +\fBsudo\fR +1.8.7 and higher. +.PP +For example, to cause +\fBsudo\fR +to only use the kernel's static list of groups for the user: +.nf +.sp +.RS 16n +Set group_source static +.RE +.fi +.sp +This setting is only available in +\fBsudo\fR +version 1.8.7 and higher. +.RE +.TP 10n +max_groups +The maximum number of user groups to retrieve from the group database. +Values less than one 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, +\fBsudo\fR +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. +.sp +This setting is only available in +\fBsudo\fR +version 1.8.7 and higher. +It should not be required in +\fBsudo\fR +versions 1.8.24 and higher and may be removed in a later release. +.TP 10n +probe_interfaces +By default, +\fBsudo\fR +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: +.nf +.sp +.RS 16n +Set probe_interfaces false +.RE +.fi +.RS 10n +.sp +This setting is only available in +\fBsudo\fR +version 1.8.10 and higher. +.RE +.SS "Debug flags" +\fBsudo\fR +versions 1.8.4 and higher support a flexible debugging framework +that can help track down what +\fBsudo\fR +is doing internally if there is a problem. +.PP +A +\fRDebug\fR +line consists of the +\fRDebug\fR +keyword, followed by the name of the program (or plugin) to debug +(\fBsudo\fR, \fBvisudo\fR, \fBsudoreplay\fR, \fBsudoers\fR), +the debug file name and a comma-separated list of debug flags. +The debug flag syntax used by +\fBsudo\fR +and the +\fBsudoers\fR +plugin is +\fIsubsystem\fR@\fIpriority\fR +but a plugin is free to use a different format so long as it does +not include a comma +(\(oq\&,\(cq). +.PP +For example: +.nf +.sp +.RS 6n +Debug sudo /var/log/sudo_debug all@warn,plugin@info +.RE +.fi +.PP +would log all debugging statements at the +\fIwarn\fR +level and higher in addition to those at the +\fIinfo\fR +level for the plugin subsystem. +.PP +As of +\fBsudo\fR +1.8.12, multiple +\fRDebug\fR +entries may be specified per program. +Older versions of +\fBsudo\fR +only support a single +\fRDebug\fR +entry per program. +Plugin-specific +\fRDebug\fR +entries are also supported starting with +\fBsudo\fR +1.8.12 and are matched by either the base name of the plugin that was loaded +(for example +\fRsudoers.so\fR) +or by the plugin's fully-qualified path name. +Previously, the +\fBsudoers\fR +plugin shared the same +\fRDebug\fR +entry as the +\fBsudo\fR +front end and could not be configured separately. +.PP +The following priorities are supported, in order of decreasing severity: +\fIcrit\fR, \fIerr\fR, \fIwarn\fR, \fInotice\fR, \fIdiag\fR, \fIinfo\fR, \fItrace\fR +and +\fIdebug\fR. +Each priority, when specified, also includes all priorities higher +than it. +For example, a priority of +\fInotice\fR +would include debug messages logged at +\fInotice\fR +and higher. +.PP +The priorities +\fItrace\fR +and +\fIdebug\fR +also include function call tracing which logs when a function is +entered and when it returns. +For example, the following trace is for the +\fBget_user_groups\fR() +function located in src/sudo.c: +.nf +.sp +.RS 6n +sudo[123] -> get_user_groups @ src/sudo.c:385 +sudo[123] <- get_user_groups @ src/sudo.c:429 := groups=10,0,5 +.RE +.fi +.PP +When the function is entered, indicated by a right arrow +\(oq->\(cq, +the program, process ID, function, source file and line number +are logged. +When the function returns, indicated by a left arrow +\(oq<-\(cq, +the same information is logged along with the return value. +In this case, the return value is a string. +.PP +The following subsystems are used by the +\fBsudo\fR +front-end: +.TP 12n +\fIall\fR +matches every subsystem +.TP 12n +\fIargs\fR +command line argument processing +.TP 12n +\fIconv\fR +user conversation +.TP 12n +\fIedit\fR +sudoedit +.TP 12n +\fIevent\fR +event subsystem +.TP 12n +\fIexec\fR +command execution +.TP 12n +\fImain\fR +\fBsudo\fR +main function +.TP 12n +\fInetif\fR +network interface handling +.TP 12n +\fIpcomm\fR +communication with the plugin +.TP 12n +\fIplugin\fR +plugin configuration +.TP 12n +\fIpty\fR +pseudo-terminal related code +.TP 12n +\fIselinux\fR +SELinux-specific handling +.TP 12n +\fIutil\fR +utility functions +.TP 12n +\fIutmp\fR +utmp handling +.PP +The +sudoers(@mansectform@) +plugin includes support for additional subsystems. +.SH "FILES" +.TP 26n +\fI@sysconfdir@/sudo.conf\fR +\fBsudo\fR +front end configuration +.SH "EXAMPLES" +.nf +.RS 0n +# +# Default @sysconfdir@/sudo.conf file +# +# Sudo plugins: +# Plugin plugin_name plugin_path plugin_options ... +# +# The plugin_path is relative to @plugindir@ 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 noexec: +# Path noexec /path/to/sudo_noexec.so +# +# Path to a shared library containing replacements for the execv(), +# execve() and fexecve() 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 @plugindir@/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 @plugindir@ + +# +# 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 +.RE +.fi +.SH "SEE ALSO" +sudo_plugin(@mansectform@), +sudoers(@mansectform@), +sudo(@mansectsu@) +.SH "HISTORY" +See the HISTORY file in the +\fBsudo\fR +distribution (https://www.sudo.ws/history.html) for a brief +history of sudo. +.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 "BUGS" +If you feel you have found a bug in +\fBsudo\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" +\fBsudo\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. |