.\" Automatically generated from the sudo_plugin_python.mdoc.in file.  Do not edit.
.\"
.\" SPDX-License-Identifier: ISC
.\"
.\" Copyright (c) 2019-2021 Robert Manner <robert.manner@oneidentity.com>
.\" Copyright (c) 2019-2025 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.
.\"
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.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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.\"
.TH "SUDO_PLUGIN_PYTHON" "5" "February 26, 2025" "Sudo @PACKAGE_VERSION@" "File Formats Manual"
.nh
.if n .ad l
.SH "NAME"
\fBsudo_plugin_python\fR
\- Sudo Plugin API (Python)
.SH "DESCRIPTION"
Starting with version 1.9,
\fBsudo\fR
plugins can be written in python.
The API closely follows the C
\fBsudo\fR
plugin API described by
sudo_plugin(@mansectform@).
.PP
The supported plugins types are:
.PP
.RS 1n
.PD 0
.TP 3n
\fB\(bu\fR
Policy plugin
.TP 3n
\fB\(bu\fR
I/O plugin
.TP 3n
\fB\(bu\fR
Audit plugin
.TP 3n
\fB\(bu\fR
Approval plugin
.TP 3n
\fB\(bu\fR
Group provider plugin
.RE
.PD
.PP
Python plugin support needs to be explicitly enabled at build time
with the configure option
\(lq--enable-python\(rq.
Python version 3.0 or higher is required.
.SS "Sudo Python Plugin Base"
A plugin written in Python should be a class in a python file that
inherits from
\fIsudo.Plugin\fR.
The
\fIsudo.Plugin\fR
base class has no real purpose other than to identify this class as a plugin.
.PP
The only implemented method is a constructor, which stores the
keyword arguments it receives as fields (member variables) in the object.
This is intended as a convenience to allow you to avoid writing the
constructor yourself.
.PP
For example:
.nf
.sp
.RS 4n
import sudo

class MySudoPlugin(sudo.Plugin):
    # example constructor (optional)
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    # example destructor (optional)
    def __del__(self):
        pass
.RE
.fi
.PP
Both the constructor and destructor are optional and can be omitted.
.PP
The customized Plugin class should define a few plugin-specific methods.
When the plugin loads,
\fBsudo\fR
will create an instance of this class and call the methods.
The actual methods required depend on the type of the plugin,
but most return an
\fIint\fR
result code, as documented in
sudo_plugin(@mansectform@),
that indicates whether or not the method was successful.
The Python sudo module defines the following constants to improve readability:
.RS 4n
.TS
l l.
.PP
\fBDefine\fR	\fBValue\fR
.PP
\fRsudo.RC.OK\fR	1
.PP
\fRsudo.RC.ACCEPT\fR	1
.PP
\fRsudo.RC.REJECT\fR	0
.PP
\fRsudo.RC.ERROR\fR	\-1
.PP
\fRsudo.RC.USAGE_ERROR\fR	\-2
.TE
.RE
.PP
If a function returns
\fRNone\fR
(for example, if it does not call return),
it will be considered to have returned
\fRsudo.RC.OK\fR.
If an exception is raised (other than sudo.PluginException), the
backtrace will be shown to the user and the plugin function will return
\fRsudo.RC.ERROR\fR.
If that is not acceptable, you must catch the exception and handle it yourself.
.PP
Instead of just returning
\fRsudo.RC.ERROR\fR
or
\fRsudo.RC.REJECT\fR
result code the plugin can also provide a message describing the problem.
This can be done by raising one of the special exceptions:
.nf
.sp
.RS 4n
raise sudo.PluginError("Message")
raise sudo.PluginReject("Message")
.RE
.fi
.PP
This added message will be used by the audit plugins.
Both exceptions inherit from
\fRsudo.PluginException\fR
.SS "Python Plugin Loader"
Running the Python interpreter and bridging between C and Python is
handled by the
\fBsudo\fR
plugin
\fI@python_plugin@\fR.
This shared object can be loaded like any other dynamic
\fBsudo\fR
plugin and should receive the path and the class name of the Python
plugin it is loading as arguments.
.PP
Example usage in
sudo.conf(@mansectform@):
.nf
.sp
.RS 4n
Plugin python_policy @python_plugin@ ModulePath=<path> ClassName=<class>
Plugin python_io @python_plugin@ ModulePath=<path> ClassName=<class>
Plugin python_audit @python_plugin@ ModulePath=<path> ClassName=<class>
Plugin python_approval @python_plugin@ ModulePath=<path> ClassName=<class>
.RE
.fi
.PP
Example group provider plugin usage in the
\fIsudoers\fR
file:
.nf
.sp
.RS 4n
Defaults group_plugin="@python_plugin@ ModulePath=<path> ClassName=<class>"
.RE
.fi
.PP
The plugin arguments are as follows:
.TP 6n
ModulePath
The path of a python file which contains the class of the sudo Python plugin.
It must be either an absolute path or a path relative to the sudo Python plugin
directory,
\fI@plugindir@/python\fR.
The parent directory of
\fIModulePath\fR
will be appended to Python's module search path (there is currently no
way to force Python to load a module from a fully-qualified path).
It is good practice to use a prefix for the module file that is unlikely
to conflict with other installed Python modules, for example,
\fIsudo_policy.py\fR.
Otherwise, if the there is an installed Python module with the same
file name as the sudo Python plugin file (without the directory),
the wrong file will be loaded.
.TP 6n
ClassName
(Optional.) The name of the class implementing the sudo Python plugin.
If not supplied, the one and only sudo.Plugin that is present in the module
will be used.
If there are multiple such plugins in the module (or none), it
will result in an error.
.SS "Policy plugin API"
Policy plugins must be registered in
sudo.conf(@mansectform@).
For example:
.nf
.sp
.RS 4n
Plugin python_policy @python_plugin@ ModulePath=<path> ClassName=<class>
.RE
.fi
.PP
Currently, only a single policy plugin may be specified in
sudo.conf(@mansectform@).
.PP
A policy plugin may have the following member functions:
.TP 6n
\fIconstructor\fR
.nf
.RS 6n
__init__(self, user_env: Tuple[str, ...], settings: Tuple[str, ...],
    version: str, user_info: Tuple[str, ...],
    plugin_options: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
Implementing this function is optional.
The default constructor will set the keyword arguments it receives
as member variables in the object.
.sp
The constructor matches the
\fBopen\fR()
function in the C
\fBsudo\fR
plugin API.
.sp
The function arguments are as follows:
.TP 6n
\fIuser_env\fR
The user's environment as a tuple of strings in
\(lqkey=value\(rq
format.
.TP 6n
\fIsettings\fR
A tuple of user-supplied
\fIsudo\fR
settings in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIversion\fR
The version of the Python Policy Plugin API.
.TP 6n
\fIuser_info\fR
A tuple of information about the user running the command in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIplugin_options\fR
The plugin options passed as arguments in the
sudo.conf(@mansectform@)
plugin registration.
This is a tuple of strings, usually (but not necessarily) in
\(lqkey=value\(rq
format.
.PP
The
\fBsudo.options_as_dict\fR()
convenience function can be used to convert
\(lqkey=value\(rq
pairs to a dictionary.
For a list of recognized keys and their supported values,
see the policy plugin
\fBopen\fR()
documentation in
sudo_plugin(@mansectform@).
.RE
.TP 6n
\fIcheck_policy\fR
.nf
.RS 6n
check_policy(self, argv: Tuple[str, ...], env_add: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
The
\fBcheck_policy\fR()
function is called by
\fBsudo\fR
to determine whether the user is allowed to run the specified command.
Implementing this function is mandatory for a policy plugin.
.sp
The function arguments are as follows:
.TP 6n
\fIargv\fR
A tuple describing the command the user wishes to run.
.TP 6n
\fIenv_add\fR
Additional environment variables specified by the user on the command line in
the form of a tuple of
\(lqkey=value\(rq
pairs.
The
\fBsudo.options_as_dict\fR()
convenience function can be used to convert them to a dictionary.
.PP
This function should return a result code or a tuple in the following format:
.nf
.sp
.RS 10n
return (rc, command_info_out, argv_out, user_env_out)
.RE
.fi
.sp
The tuple values are as follows:
.TP 6n
\fIrc\fR
The result of the policy check, one of the
\fRsudo.RC.*\fR
constants.
\fRsudo.RC.ACCEPT\fR
if the command is allowed,
\fRsudo.RC.REJECT\fR
if not allowed,
\fRsudo.RC.ERROR\fR
for a general error, or
\fRsudo.RC.USAGE_ERROR\fR
for a usage error.
.TP 6n
\fIcommand_info_out\fR
Optional (only required when the command is accepted).
Information about the command being run in the form of
\(lqkey=value\(rq
strings.
.sp
To accept a command, at the very minimum the plugin must set in the
\fIcommand\fR,
\fIrunas_uid\fR,
and
\fIrunas_gid\fR
keys.
.sp
For a list of recognized keys and supported values,
see the
\fBcheck_policy\fR()
documentation in
sudo_plugin(@mansectform@).
.TP 6n
\fIargv_out\fR
Optional (only required when the command is accepted).
The arguments to pass to the
execve(2)
system call when executing the command.
.TP 6n
\fIuser_env_out\fR
Optional (only required when the command is accepted).
The environment to use when executing the command in the form of a
tuple of strings in
\(lqkey=value\(rq
format.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIinit_session\fR
.nf
.RS 6n
init_session(self, user_pwd: Tuple, user_env: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
Perform session setup (optional).
The
\fBinit_session\fR()
function is called before
\fBsudo\fR
sets up the
execution environment for the command before any user-ID or group-ID changes.
.sp
The function arguments are as follows:
.TP 6n
\fIuser_pwd\fR
A tuple describing the user's passwd entry.
Convertible to
\fIpwd.struct_passwd or\fR
\fRNone\fR
if the user is not present in the password database.
.sp
Example conversion:
.nf
.RS 12n
user_pwd = pwd.struct_passwd(user_pwd) if user_pwd else None
.RE
.fi
.TP 6n
\fIuser_env\fR
The environment the command will run in.
This is a tuple of strings in
\(lqkey=value\(rq
format.
.PP
This function should return a result code or a tuple in the following format:
.nf
.sp
.RS 10n
return (rc, user_env_out)
.RE
.fi
.sp
The tuple values are as follows:
.TP 6n
\fIrc\fR
The result of the session init, one of the
\fRsudo.RC.*\fR
constants.
\fRsudo.RC.OK\fR
on success, 0 on failure, or
\fRsudo.RC.ERROR\fR
if an error occurred.
.TP 6n
\fIuser_env_out\fR
Optional.
If the
\fBinit_session\fR()
function needs to modify the user environment, it can return the new
environment in
\fIuser_env_out\fR.
If this is omitted, no changes will be made to
\fIuser_env\fR.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIlist\fR
.nf
.RS 6n
list(self, argv: Tuple[str, ...], is_verbose: int, user: str)
.RE
.fi
.RS 6n
.sp
List available privileges for the invoking user.
.sp
The function arguments are as follows:
.TP 6n
\fIargv\fR
If not set to
\fRNone\fR,
an argument vector describing a command the user wishes to check
against the policy.
.TP 6n
\fIis_verbose\fR
Flag indicating whether to list in verbose mode or not.
.TP 6n
\fIuser\fR
The name of a different user to list privileges for if the policy allows it.
If
\fRNone\fR,
the plugin should list the privileges of the invoking user.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIvalidate\fR
.nf
.RS 6n
validate(self)
.RE
.fi
.RS 6n
.sp
For policy plugins that cache authentication credentials,
this function is used to validate and cache the credentials (optional).
.RE
.TP 6n
\fIinvalidate\fR
.nf
.RS 6n
invalidate(self, remove: int)
.RE
.fi
.RS 6n
.sp
For policy plugins that cache authentication credentials,
this function is used to invalidate the credentials (optional).
.sp
The function arguments are as follows:
.TP 6n
\fIremove\fR
If this flag is set, the plugin may remove the credentials instead of simply
invalidating them.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIshow_version\fR
.nf
.RS 6n
show_version(self, is_verbose: int)
.RE
.fi
.RS 6n
.sp
Display the plugin version information to the user.
The
\fBsudo.log_info\fR()
function should be used.
.sp
The function arguments are as follows:
.TP 6n
\fIis_verbose\fR
A flag to indicate displaying more verbose information.
Currently this is 1 if
\(oqsudo -V\(cq
is run as the root user.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIclose\fR
.br
.nf
.RS 6n
close(self, exit_status: int, error: int)
.RE
.fi
.RS 6n
.sp
Called when a command finishes executing.
.sp
Works the same as the
\fBclose\fR()
function in the C
\fBsudo\fR
plugin API, except that it only gets called if
\fBsudo\fR
attempts to execute the command.
.sp
The function arguments are as follows:
.TP 6n
\fIexit_status\fR
The exit status of the command if was executed, otherwise \-1.
.TP 6n
\fIerror\fR
.br
If the command could not be executed,
this is set to the value of errno set by the
execve(2)
system call, otherwise 0.
.PD 0
.PP
.RE
.PD
.SS "Policy plugin example"
Sudo ships with an example Python policy plugin.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 0n
Plugin python_policy @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_policy_plugin.py \e
    ClassName=SudoPolicyPlugin
.RE
.fi
.PP
Only one policy plugin can be enabled at a time so you must disable
any other policy plugin listed in
\fI@sysconfdir@/sudo.conf\fR,
such as
sudoers(@mansectform@).
.SS "I/O plugin API"
I/O plugins must be registered in
sudo.conf(@mansectform@).
For example:
.nf
.sp
.RS 4n
Plugin python_io @python_plugin@ ModulePath=<path> ClassName=<class>
.RE
.fi
.PP
Sudo supports loading multiple I/O plugins.
Currently only 8 python I/O plugins can be loaded at once.
.PP
An I/O plugin may have the following member functions:
.TP 6n
\fIconstructor\fR
.nf
.RS 6n
__init__(self, user_env: Tuple[str, ...], settings: Tuple[str, ...],
    version: str, user_info: Tuple[str, ...],
    plugin_options: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
Implementing this function is optional.
The default constructor will set the keyword arguments it receives
as member variables in the object.
.sp
The constructor matches the
\fBopen\fR()
function in the C
\fBsudo\fR
plugin API.
.sp
The function arguments are as follows:
.TP 6n
\fIuser_env\fR
The user's environment as a tuple of strings in
\(lqkey=value\(rq
format.
.TP 6n
\fIsettings\fR
A tuple of user-supplied
\fIsudo\fR
settings in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIversion\fR
The version of the Python I/O Plugin API.
.TP 6n
\fIuser_info\fR
A tuple of information about the user running the command in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIplugin_options\fR
The plugin options passed as arguments in the
sudo.conf(@mansectform@)
plugin registration.
This is a tuple of strings, usually (but not necessarily) in
\(lqkey=value\(rq
format.
.PP
The
\fBsudo.options_as_dict\fR()
convenience function can be used to convert
\(lqkey=value\(rq
pairs to a dictionary.
For a list of recognized keys and their supported values,
see the I/O plugin
\fBopen\fR()
documentation in
sudo_plugin(@mansectform@).
.RE
.TP 6n
\fIopen\fR
.nf
.RS 6n
open(self, argv: Tuple[str, ...],
    command_info: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
Receives the command the user wishes to run.
.sp
Works the same as the
\fBopen\fR()
function in the C
\fBsudo\fR
plugin API except that:
.sp
.RS 7n
.PD 0
.TP 3n
\fB\(bu\fR
It only gets called when there is a command to be executed
(and not for a version query for example).
.TP 3n
\fB\(bu\fR
Other arguments of the C API
\fBopen\fR()
function are received through the constructor.
.RE
.sp
The function arguments are as follows:
.PD
.TP 6n
\fIargv\fR
A tuple of the arguments describing the command the user wishes to run.
.TP 6n
\fIcommand_info\fR
Information about the command being run in the form of
\(lqkey=value\(rq
strings.
.PP
The
\fBsudo.options_as_dict\fR()
convenience function can be used to convert
\(lqkey=value\(rq
pairs to a dictionary.
For a list of recognized keys and their supported values,
see the I/O plugin
\fBopen\fR()
documentation in
sudo_plugin(@mansectform@).
.sp
The
\fBopen\fR()
function should return a result code, one of the
\fRsudo.RC.*\fR
constants.
If the function returns
\fRsudo.RC.REJECT\fR,
no I/O will be sent to the plugin.
.RE
.TP 6n
\fIlog_ttyin\fR, \fIlog_ttyout\fR, \fIlog_stdin\fR, \fIlog_stdout\fR, \fIlog_stderr\fR
.nf
.RS 6n
log_ttyin(self, buf: str) -> int
log_ttyout(self, buf: str) -> int
log_stdin(self, buf: str) -> int
log_stdout(self, buf: str) -> int
log_stderr(self, buf: str) -> int
.RE
.fi
.RS 6n
.sp
Receive the user input or output of the terminal device and
application standard input, standard output, or standard error.
See the matching calls in
sudo_plugin(@mansectform@).
.sp
The function arguments are as follows:
.TP 6n
\fIbuf\fR
The input (or output) buffer in the form of a string.
.PP
The function should return a result code, one of the
\fRsudo.RC.*\fR
constants.
.sp
If
\fRsudo.RC.ERROR\fR
is returned, the running command will be terminated and all of the
plugin's logging functions will be disabled.
Other I/O logging plugins will still receive any remaining
input or output that has not yet been processed.
.sp
If an input logging function rejects the data by returning
\fRsudo.RC.REJECT\fR,
the command will be terminated and the data will not be passed to the
command, though it will still be sent to any other I/O logging plugins.
If an output logging function rejects the data by returning
\fRsudo.RC.REJECT\fR,
the command will be terminated and the data will not be written to the
terminal, though it will still be sent to any other I/O logging plugins.
.RE
.TP 6n
\fIchange_winsize\fR
.nf
.RS 6n
change_winsize(self, line: int, cols: int) -> int
.RE
.fi
.RS 6n
.sp
Called whenever the window size of the terminal changes.
The function arguments are as follows:
.TP 6n
\fIline\fR
The number of lines of the terminal.
.TP 6n
\fIcols\fR
The number of columns of the terminal.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIlog_suspend\fR
.nf
.RS 6n
log_suspend(self, signo: int) -> int
.RE
.fi
.RS 6n
Called whenever a command is suspended or resumed.
.sp
The function arguments are as follows:
.TP 6n
\fIsigno\fR
.br
The number of the signal that caused the command to be suspended or
\fRSIGCONT\fR
if the command was resumed.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIshow_version\fR
.nf
.RS 6n
show_version(self, is_verbose: int)
.RE
.fi
.RS 6n
Display the plugin version information to the user.
The
\fBsudo.log_info\fR()
function should be used.
.sp
The function arguments are as follows:
.TP 6n
\fIis_verbose\fR
A flag to indicate displaying more verbose information.
Currently this is 1 if
\(oqsudo -V\(cq
is run as the root user.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIclose\fR
.br
.nf
.RS 6n
close(self, exit_status: int, error: int) -> None
.RE
.fi
.RS 6n
Called when a command finishes execution.
.sp
Works the same as the
\fBclose\fR()
function in the C
\fBsudo\fR
plugin API, except that it only gets called if
\fBsudo\fR
attempts to execute the command.
.sp
The function arguments are as follows:
.TP 6n
\fIexit_status\fR
The exit status of the command if was executed, otherwise \-1.
.TP 6n
\fIerror\fR
.br
If the command could not be executed,
this is set to the value of errno set by the
execve(2)
system call, otherwise 0.
.PD 0
.PP
.RE
.PD
.SS "I/O plugin example"
Sudo ships with a Python I/O plugin example.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 4n
Plugin python_io @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_io_plugin.py \e
    ClassName=SudoIOPlugin
.RE
.fi
.SS "Audit plugin API"
Audit plugins must be registered in
sudo.conf(@mansectform@).
For example:
.nf
.sp
.RS 4n
Plugin python_audit @python_plugin@ ModulePath=<path> ClassName=<class>
.RE
.fi
.PP
Sudo supports loading multiple audit plugins.
Currently only 8 python audit plugins can be loaded at once.
.PP
An audit plugin may have the following member functions
(all of which are optional):
.TP 6n
\fIconstructor\fR
.nf
.RS 6n
__init__(self, user_env: Tuple[str, ...], settings: Tuple[str, ...],
    version: str, user_info: Tuple[str, ...], plugin_options: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
The default constructor will set the keyword arguments it receives
as member variables in the object.
.sp
The constructor matches the
\fBopen\fR()
function in the C
\fBsudo\fR
plugin API.
.sp
The function arguments are as follows:
.TP 6n
\fIuser_env\fR
The user's environment as a tuple of strings in
\(lqkey=value\(rq
format.
.TP 6n
\fIsettings\fR
A tuple of user-supplied
\fIsudo\fR
settings in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIversion\fR
The version of the Python Audit Plugin API.
.TP 6n
\fIuser_info\fR
A tuple of information about the user running the command in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIplugin_options\fR
The plugin options passed as arguments in the
sudo.conf(@mansectform@)
plugin registration.
This is a tuple of strings, usually (but not necessarily) in
\(lqkey=value\(rq
format.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIopen\fR
.nf
.RS 6n
open(self, submit_optind: int,
    submit_argv: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
The function arguments are as follows:
.TP 6n
\fIsubmit_optind\fR
The index into
\fIsubmit_argv\fR
that corresponds to the first entry that is not a command line option.
.TP 6n
\fIsubmit_argv\fR
The argument vector sudo was invoked with, including all command line options.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIclose\fR
.br
.nf
.RS 6n
close(self, status_type: int, status: int) -> None
.RE
.fi
.RS 6n
.sp
Called when sudo is finished, shortly before it exits.
.sp
The function arguments are as follows:
.TP 6n
\fIstatus_type\fR
The type of status being passed.
One of the
\fRsudo.EXIT_REASON.*\fR
constants.
.TP 6n
\fIstatus\fR
Depending on the value of
\fIstatus_type\fR,
this value is either
ignored, the command's exit status as returned by the
wait(2)
system call, the value of
\fIerrno\fR
set by the
execve(2)
system call, or the value of
\fIerrno\fR
resulting from an error in the
\fBsudo\fR
front-end.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIshow_version\fR
.nf
.RS 6n
show_version(self, is_verbose: int) -> int
.RE
.fi
.RS 6n
.sp
Display the plugin version information to the user.
The
\fBsudo.log_info\fR()
function should be used.
.sp
The function arguments are as follows:
.TP 6n
\fIis_verbose\fR
A flag to indicate displaying more verbose information.
Currently this is 1 if
\(oqsudo -V\(cq
is run as the root user.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIaccept\fR
.nf
.RS 6n
accept(self, plugin_name: str, plugin_type: int, command_info: Tuple[str, ...],
       run_argv: Tuple[str, ...], run_envp: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
This function is called when a command or action is accepted by a policy
or approval plugin.
The function arguments are as follows:
.TP 6n
plugin_name
The name of the plugin that accepted the command or
\(lqsudo\(rq
for the
\fBsudo\fR
front-end.
.TP 6n
plugin_type
The type of plugin that accepted the command, currently either
\fRsudo.PLUGIN_TYPE.POLICY\fR,
\fRsudo.PLUGIN_TYPE.APPROVAL\fR,
or
\fRsudo.PLUGIN_TYPE.SUDO\fR.
The
\fBaccept\fR()
function is called multiple times--once for each policy or approval
plugin that succeeds and once for the sudo front-end.
When called on behalf of the sudo front-end,
\fIcommand_info\fR
may include information from an I/O logging plugin as well.
.sp
Typically, an audit plugin is interested in either the accept status from
the
\fBsudo\fR
front-end or from the various policy and approval plugins, but not both.
It is possible for the policy plugin to accept a command that is
later rejected by an approval plugin, in which case the audit
plugin's
\fBaccept\fR()
and
\fBreject\fR()
functions will
\fIboth\fR
be called.
.TP 6n
command_info
A vector of information describing the command being run.
See the
sudo_plugin(@mansectform@)
manual for possible values.
.TP 6n
run_argv
Argument vector describing a command that will be run.
.TP 6n
run_envp
The environment the command will be run with.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIreject\fR
.nf
.RS 6n
reject(self, plugin_name: str, plugin_type: int, audit_msg: str,
       command_info: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
This function is called when a command or action is rejected by the policy
plugin.
The function arguments are as follows:
.TP 6n
plugin_name
The name of the plugin that rejected the command.
.TP 6n
plugin_type
The type of plugin that rejected the command, currently either
\fRsudo.PLUGIN_TYPE.POLICY\fR,
\fRsudo.PLUGIN_TYPE.APPROVAL\fR,
or
\fRsudo.PLUGIN_TYPE.IO\fR.
.sp
Unlike the
\fBaccept\fR()
function, the
\fBreject\fR()
function is not called on behalf of the
\fBsudo\fR
front-end.
.TP 6n
audit_msg
An optional string describing the reason the command was rejected by the plugin.
If the plugin did not provide a reason, audit_msg will be
\fRNone\fR.
.TP 6n
command_info
A vector of information describing the rejected command.
See the
sudo_plugin(@mansectform@)
manual for possible values.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIerror\fR
.br
.nf
.RS 6n
error(self, plugin_name: str, plugin_type: int, audit_msg: str,
      command_info: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
This function is called when a plugin or the
\fBsudo\fR
front-end returns an error.
The function arguments are as follows:
.TP 6n
plugin_name
The name of the plugin that generated the error or
\(lqsudo\(rq
for the
\fBsudo\fR
front-end.
.TP 6n
plugin_type
The type of plugin that generated the error, or
\fRSUDO_FRONT_END\fR
for the
\fBsudo\fR
front-end.
.TP 6n
audit_msg
An optional string describing the plugin error.
If the plugin did not provide a description, it will be
\fRNone\fR.
.TP 6n
command_info
A vector of information describing the command.
See the
sudo_plugin(@mansectform@)
manual for possible values.
.PD 0
.PP
.RE
.PD
.SS "Audit plugin example"
Sudo ships with a Python Audit plugin example.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 4n
Plugin python_audit @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_audit_plugin.py \e
    ClassName=SudoAuditPlugin
.RE
.fi
.PP
It will log the plugin accept / reject / error results to the output.
.SS "Approval plugin API"
Approval plugins must be registered in
sudo.conf(@mansectform@).
For example:
.nf
.sp
.RS 4n
Plugin python_approval @python_plugin@ ModulePath=<path> ClassName=<class>
.RE
.fi
.PP
Sudo supports loading multiple approval plugins.
Currently only 8 python approval plugins can be loaded at once.
.PP
An approval plugin may have the following member functions:
.TP 6n
\fIconstructor\fR
.nf
.RS 6n
__init__(self, user_env: Tuple[str, ...], settings: Tuple[str, ...],
    version: str, user_info: Tuple[str, ...], plugin_options: Tuple[str, ...],
    submit_optind: int, submit_argv: Tuple[str, ...])
.RE
.fi
.RS 6n
.sp
Optional.
The default constructor will set the keyword arguments it receives
as member variables in the object.
.sp
The constructor matches the
\fBopen\fR()
function in the C
\fBsudo\fR
plugin API.
.sp
The function arguments are as follows:
.TP 6n
\fIuser_env\fR
The user's environment as a tuple of strings in
\(lqkey=value\(rq
format.
.TP 6n
\fIsettings\fR
A tuple of user-supplied
\fIsudo\fR
settings in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIversion\fR
The version of the Python Approval Plugin API.
.TP 6n
\fIuser_info\fR
A tuple of information about the user running the command in the form of
\(lqkey=value\(rq
strings.
.TP 6n
\fIplugin_options\fR
The plugin options passed as arguments in the
sudo.conf(@mansectform@)
plugin registration.
This is a tuple of strings, usually (but not necessarily) in
\(lqkey=value\(rq
format.
.TP 6n
\fIsubmit_optind\fR
The index into
\fIsubmit_argv\fR
that corresponds to the first entry that is not a command line option.
.TP 6n
\fIsubmit_argv\fR
The argument vector sudo was invoked with, including all command line options.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIshow_version\fR
.nf
.RS 6n
show_version(self, is_verbose: int) -> int
.RE
.fi
.RS 6n
.sp
Display the version.
(Same as for all the other plugins.)
.RE
.TP 6n
\fIcheck\fR
.br
.nf
.RS 6n
check(self, command_info: Tuple[str, ...], run_argv: Tuple[str, ...],
      run_env: Tuple[str, ...]) -> int
.RE
.fi
.RS 6n
.sp
This function is called after policy plugin's check_policy has succeeded.
It can reject execution of the command by returning sudo.RC.REJECT or
raising the special exception:
.nf
.sp
.RS 10n
raise sudo.PluginReject("some message")
.RE
.fi
.sp
with the message describing the problem.
In the latter case, the audit plugins will get the description.
.sp
The function arguments are as follows:
.TP 6n
command_info
A vector of information describing the command that will run.
See the
sudo_plugin(@mansectform@)
manual for possible values.
.TP 6n
run_argv
Argument vector describing a command that will be run.
.TP 6n
run_env
The environment the command will be run with.
.PD 0
.PP
.RE
.PD
.SS "Approval plugin example"
Sudo ships with a Python Approval plugin example.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 4n
Plugin python_approval @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_approval_plugin.py \e
    ClassName=BusinessHoursApprovalPlugin
.RE
.fi
.PP
It will only allow execution of commands in the "business hours" (from Monday
to Friday between 8:00 and 17:59:59).
.SS "Sudoers group provider plugin API"
A group provider plugin is registered in the
sudoers(@mansectform@)
file.
For example:
.nf
.sp
.RS 4n
Defaults group_plugin="@python_plugin@ ModulePath=<path> ClassName=<class>"
.RE
.fi
.PP
Currently, only a single group plugin can be registered in
\fIsudoers\fR.
.PP
A group provider plugin may have the following member functions:
.TP 6n
\fIconstructor\fR
.nf
.RS 6n
__init__(self, args: Tuple[str, ...], version: str)
.RE
.fi
.RS 6n
.sp
Implementing this function is optional.
The default constructor will set the keyword arguments it receives
as member variables in the object.
.sp
The function arguments are as follows:
.TP 6n
\fIargs\fR
The plugin options passed as arguments in the
\fIsudoers\fR
file plugin registration.
All the arguments are free form strings (not necessarily in
\(lqkey=value\(rq
format).
.TP 6n
\fIversion\fR
The version of the Python Group Plugin API.
.PD 0
.PP
.RE
.PD
.TP 6n
\fIquery\fR
.br
.nf
.RS 6n
query(self, user: str, group: str, user_pwd: Tuple)
.RE
.fi
.RS 6n
.sp
The
\fBquery\fR()
function is used to ask the group plugin whether
\fIuser\fR
is a member of
\fIgroup\fR.
This method is required.
.RE
.PP
The function arguments are as follows:
.TP 6n
\fIuser\fR
The name of the user being looked up in the external group database.
.TP 6n
\fIgroup\fR
.br
The name of the group being queried.
.TP 6n
\fIuser_pwd\fR
The password database entry for the user, if any.
If
\fIuser\fR
is not present in the password database,
\fIuser_pwd\fR
will be
\fRNULL\fR.
.SS "Group plugin example"
Sudo ships with a Python group plugin example.
To try it, register it in the
\fIsudoers\fR
file by adding the following lines:
.nf
.sp
.RS 4n
Defaults group_plugin="@python_plugin@ \e
    ModulePath=@EXAMPLES@/example_group_plugin.py \e
    ClassName=SudoGroupPlugin"
.RE
.fi
.PP
The example plugin will tell
\fBsudo\fR
that the user
\fItest\fR
is part of the non-Unix group
\fImygroup\fR.
If you add a rule that uses this group, it will affect the
\fItest\fR
user.
For example:
.nf
.sp
.RS 4n
%:mygroup ALL=(ALL) NOPASSWD: ALL
.RE
.fi
.PP
Will allow user
\fItest\fR
to run
\fBsudo\fR
without a password.
.SS "Hook function API"
The hook function API is currently not supported for plugins
written in Python.
.SS "Conversation API"
A Python plugin can interact with the user using the
\fBsudo.conv\fR()
function which displays one or more messages described by the
\fRsudo.ConvMessage\fR
class.
This is the Python equivalent of the
\fBconversation\fR()
function in the C
\fBsudo\fR
plugin API.
A plugin should not attempt to read directly from the standard input or
the user's tty (neither of which are guaranteed to exist).
.PP
The
\fRsudo.ConvMessage\fR
class specifies how the user interaction should occur:
.nf
.sp
.RS 4n
sudo.ConvMessage(msg_type: int, msg: str, timeout: int)
.RE
.fi
.PP
\fRsudo.ConvMessage\fR
member variables:
.TP 6n
\fImsg_type\fR
Specifies the type of the conversation.
See the
\fRsudo.CONV.*\fR
constants below.
.TP 6n
\fImsg\fR
The message to display to the user.
The caller must include a trailing newline in
\fImsg\fR
if one is to be displayed.
.TP 6n
\fItimeout\fR
Optional.
The maximum amount of time for the conversation in seconds.
If the timeout is exceeded, the
\fBsudo.conv\fR()
function will raise a
\fRsudo.ConversationInterrupted\fR
exception.
The default is to wait forever (no timeout).
.PP
To specify the message type, the following constants are available:
.PP
.RS 1n
.PD 0
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.PROMPT_ECHO_OFF\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.PROMPT_ECHO_ON\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.ERROR_MSG\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.INFO_MSG\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.PROMPT_MASK\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.PROMPT_ECHO_OK\fR
.TP 3n
\fB\(bu\fR
\fRsudo.CONV.PREFER_TTY\fR
.RE
.PD
.PP
See the
sudo_plugin(@mansectform@)
manual for a description of the message types.
.PP
The
\fBsudo.conv\fR()
function performs the actual user interaction:
.nf
.sp
.RS 4n
sudo.conv(message(s), on_suspend=suspend_function,
    on_resume=resume_function)
.RE
.fi
.PP
The function arguments are as follows:
.TP 6n
\fImessage(s)\fR
One of more messages (of type
\fRsudo.ConvMessage\fR),
each describing a conversation.
At least one message is required.
.TP 6n
\fIon_suspend\fR
An optional callback function which gets called if the conversation
is suspended, for example by the user pressing control-Z.
The specified function must take a single argument which will be filled
with the number of the signal that caused the process to be suspended.
.TP 6n
\fIon_resume\fR
An optional callback function which gets called when the previously
suspended conversation is resumed.
The specified function must take a single argument which will be filled
with the number of the signal that caused the process to be suspended.
.PP
The
\fBsudo.conv\fR()
function can raise the following exceptions:
.TP 6n
\fRsudo.SudoException\fR
If the conversation fails, for example when the conversation function is not
available.
.TP 6n
\fRsudo.ConversationInterrupted\fR
If the conversation function returns an error, e.g., the timeout passed
or the user interrupted the conversation by pressing control-C.
.SS "Conversation example"
Sudo ships with an example plugin demonstrating the Python conversation API.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 4n
Plugin python_io @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_conversation.py \e
    ClassName=ReasonLoggerIOPlugin
.RE
.fi
.SS "Information / error display API"
.nf
.RS 0n
sudo.log_info(string(s), sep=" ", end="\en")
sudo.log_error(string(s), sep=" ", end="\en")
.RE
.fi
.PP
To display information to the user, the
\fBsudo.log_info\fR()
function can be used.
To display error messages, use
\fBsudo.log_error\fR().
The syntax is similar to the Python
\fBprint\fR()
function.
.PP
The function arguments are as follows:
.TP 6n
\fIstring(s)\fR
One or more strings to display.
.TP 6n
\fIsep\fR
An optional string which will be used as the separator between the
specified strings.
The default is a space character,
(\(oq\ \(cq).
.TP 6n
\fIend\fR
An optional string which will be displayed at the end of the message.
The default is a new line character
(\(oq\en\(cq).
.SS "Debug API"
Debug messages are not visible to the user and are only logged debugging
is explicitly enabled in
sudo.conf(@mansectform@).
Python plugins can use the
\fBsudo.debug\fR()
function to make use of
\fBsudo\fR's
debug system.
.PP
\fIEnabling debugging in sudo.conf\fR
.PP
To enable debug messages, add a
\fIDebug\fR
line to
sudo.conf(@mansectform@)
with the program set to
\fI@python_plugin@\fR.
For example, to store debug output in
\fI@log_dir@/sudo_python_debug\fR,
use a line like the following:
.nf
.sp
.RS 4n
Debug @python_plugin@ @log_dir@/sudo_python_debug \e
    plugin@trace,c_calls@trace
.RE
.fi
.PP
The debug options are in the form of multiple
\(lqsubsystem@level\(rq
strings, separated by commas
(\(oq\&,\(cq).
For example to just see the debug output of
\fBsudo.debug\fR()
calls, use:
.nf
.sp
.RS 4n
Debug @python_plugin@ @log_dir@/sudo_python_debug plugin@trace
.RE
.fi
.PP
See
sudo_conf(@mansectform@)
for more details.
.PP
The most interesting subsystems for Python plugin development are:
.TP 6n
\fIplugin\fR
Logs each
\fBsudo.debug\fR()
API call.
.TP 6n
\fIpy_calls\fR
Logs whenever a C function calls into the python module.
For example, calling the
\fB__init__\fR()
function.
.TP 6n
\fIc_calls\fR
Logs whenever python calls into a C
\fBsudo\fR
API function.
.TP 6n
\fIinternal\fR
Logs internal functions of the python language wrapper plugin.
.TP 6n
\fIsudo_cb\fR
Logs when
\fBsudo\fR
calls into the python plugin API.
.TP 6n
\fIload\fR
Logs python plugin loading / unloading events.
.PP
You can also specify
\(lqall\(rq
as the subsystem name to log debug messages for all subsystems.
.PP
The
\fBsudo.debug\fR()
function is defined as:
.nf
.sp
.RS 4n
sudo.debug(level, message(s))
.RE
.fi
.PP
The function arguments are as follows:
.TP 6n
\fIlevel\fR
.br
an integer, use one of the log level constants below
.TP 6n
\fImessage(s)\fR
one or more messages to log
.PP
\fIAvailable log levels:\fR
.TS
l l l.
.PP
\fBsudo.conf name\fR	\fBPython constant\fR	\fBdescription\fR
.PP
crit	\fRsudo.DEBUG.CRIT\fR	critical errors
.PP
err	\fRsudo.DEBUG.ERROR\fR	non-critical errors
.PP
warn	\fRsudo.DEBUG.WARN\fR	non-fatal warnings
.PP
notice	\fRsudo.DEBUG.NOTICE\fR	non-error condition notices
.PP
diag	\fRsudo.DEBUG.DIAG\fR	diagnostic messages
.PP
info	\fRsudo.DEBUG.INFO\fR	informational message
.PP
trace	\fRsudo.DEBUG.TRACE\fR	log function enter/exit
.PP
debug	\fRsudo.DEBUG.DEBUG\fR	very verbose debugging
.TE
.PP
\fIUsing the logging module\fR
.PP
Alternatively, a plugin can use the built in logging module of Python as well.
Sudo adds its log handler to the root logger, so by default all output of a
logger will get forwarded to sudo log system, as it would call sudo.debug.
.PP
The log handler of sudo will map each Python log level of a message to
the appropriate sudo debug level.
The sudo debug system will only receive messages that are not filtered
out by the Python loggers.
For example, the log level of the python logger will be an additional
filter for the log messages, and is usually very different from
what level is set in sudo.conf for the sudo debug system.
.SS "Debug example"
Sudo ships with an example debug plugin.
To try it, register it by adding the following lines to
\fI@sysconfdir@/sudo.conf\fR:
.nf
.sp
.RS 4n
Plugin python_io @python_plugin@ \e
    ModulePath=@EXAMPLES@/example_debugging.py \e
    ClassName=DebugDemoPlugin

Debug @python_plugin@ \e
    @log_dir@/sudo_python_debug plugin@trace,c_calls@trace
.RE
.fi
.SS "Option conversion API"
The Python plugin API includes two convenience functions to
convert options in
\(lqkey=value\(rq
format to a dictionary and vice versa.
.TP 6n
options_as_dict
.nf
.RS 6n
options_as_dict(options)
.RE
.fi
.RS 6n
.sp
The function arguments are as follows:
.TP 6n
\fIoptions\fR
An iterable (tuple, list, etc.) of strings, each in
\(lqkey=value\(rq
format.
This is how the plugin API passes options and settings to a Python plugin.
.PP
The function returns the resulting dictionary.
Each string of the passed in
\fIoptions\fR
will be split at the first equal sign
(\(oq\&=\(cq)
into a
\fIkey\fR
and
\fIvalue\fR.
Dictionary keys will never contain this symbol (but values may).
.RE
.TP 6n
options_from_dict
.nf
.RS 6n
options_from_dict(options_dict)
.RE
.fi
.RS 6n
.sp
The function arguments are as follows:
.TP 6n
\fIoptions_dict\fR
A dictionary where both the key and the value are strings.
The key should not contain an equal sign
(\(oq\&=\(cq),
otherwise the resulting string will have a different meaning.
However, this is not currently enforced.
.PP
The function returns a tuple containing the strings in
\(lqkey=value\(rq
form for each key and value in the
\fIoptions_dict\fR
dictionary passed in.
This is how the plugin API accepts options and settings.
.RE
.SH "PLUGIN API CHANGELOG (Python)"
None yet
.SH "LIMITATIONS"
A maximum of 8 python I/O plugins can be loaded at once.
If
\fI@sysconfdir@/sudo.conf\fR
contains more, those will be rejected with a warning message.
.PP
The Event API and the hook function API is currently not accessible
for Python plugins.
.SH "SEE ALSO"
sudo.conf(@mansectform@),
sudo_plugin(@mansectform@),
sudoers(@mansectform@),
sudo(@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.md file in the
\fBsudo\fR
distribution (https://www.sudo.ws/about/contributors/) for an
exhaustive list of people who have contributed to
\fBsudo\fR.
.SH "BUGS"
Python plugin support is currently considered experimental.
.PP
If you believe you have found a bug in
\fBsudo_plugin_python\fR,
you can either file a bug report in the sudo bug database,
https://bugzilla.sudo.ws/, or open an issue at
https://github.com/sudo-project/sudo/issues.
If you would prefer to use email, messages may be sent to the
sudo-workers mailing list,
https://www.sudo.ws/mailman/listinfo/sudo-workers (public)
or <sudo@sudo.ws> (private).
.PP
Please do not report security vulnerabilities through public GitHub
issues, Bugzilla or mailing lists.
Instead, report them via email to <Todd.Miller@sudo.ws>.
You may encrypt your message with PGP if you would like, using
the key found at https://www.sudo.ws/dist/PGPKEYS.
.SH "SECURITY CONSIDERATIONS"
All Python plugin handling is implemented inside the
\fI@python_plugin@\fR
dynamic plugin.
Therefore, if no Python plugin is registered in
sudo.conf(@mansectform@)
or the
\fIsudoers\fR
file,
\fBsudo\fR
will not load the Python interpreter or the Python libraries.
.PP
As
\fBsudo\fR
runs plugins as
\fBroot\fR,
care must be taken when writing Python plugins to avoid creating
security vulnerabilities, just as one would when writing plugins
in C.
.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.md file distributed with
\fBsudo\fR
or https://www.sudo.ws/about/license/ for complete details.
