manpagez: man pages & more
man sudo_plugin(5)
Home | html | info | man
sudo_plugin(5)                File Formats Manual               sudo_plugin(5)


NAME

     sudo_plugin - Sudo Plugin API


DESCRIPTION

     Starting with version 1.8, sudo supports a plugin API for policy and
     session logging.  Plugins may be compiled as dynamic shared objects (the
     default on systems that support them) or compiled statically into the
     sudo binary itself.  By default, the sudoers plugin provides audit,
     security policy and I/O logging capabilities.  Via the plugin API, sudo
     can be configured to use alternate plugins provided by third parties.
     The plugins to be used are specified in the sudo.conf(5) file.

     The API is versioned with a major and minor number.  The minor version
     number is incremented when additions are made.  The major number is
     incremented when incompatible changes are made.  A plugin should be check
     the version passed to it and make sure that the major version matches.

     The plugin API is defined by the <sudo_plugin.h> header file.

   Policy plugin API
     A policy plugin must declare and populate a struct policy_plugin in the
     global scope.  This structure contains pointers to the functions that
     implement the sudo policy checks.  The name of the symbol should be
     specified in sudo.conf(5) along with a path to the plugin so that sudo
     can load it.

     struct policy_plugin {
     #define SUDO_POLICY_PLUGIN     1
         unsigned int type; /* always SUDO_POLICY_PLUGIN */
         unsigned int version; /* always SUDO_API_VERSION */
         int (*open)(unsigned int version, sudo_conv_t conversation,
             sudo_printf_t sudo_plugin_printf, char * const settings[],
             char * const user_info[], char * const user_env[],
             char * const plugin_options[], const char **errstr);
         void (*close)(int exit_status, int error);
         int (*show_version)(int verbose);
         int (*check_policy)(int argc, char * const argv[],
             char *env_add[], char **command_info[],
             char **argv_out[], char **user_env_out[], const char **errstr);
         int (*list)(int argc, char * const argv[], int verbose,
             const char *user, const char **errstr);
         int (*validate)(const char **errstr);
         void (*invalidate)(int rmcred);
         int (*init_session)(struct passwd *pwd, char **user_env[],
             const char **errstr);
         void (*register_hooks)(int version,
            int (*register_hook)(struct sudo_hook *hook));
         void (*deregister_hooks)(int version,
            int (*deregister_hook)(struct sudo_hook *hook));
         struct sudo_plugin_event * (*event_alloc)(void);
     };

     A struct policy_plugin has the following fields:

     type  The type field should always be set to SUDO_POLICY_PLUGIN.

     version
           The version field should be set to SUDO_API_VERSION.

           This allows sudo to determine the API version the plugin was built
           against.

     open
           int (*open)(unsigned int version, sudo_conv_t conversation,
               sudo_printf_t sudo_plugin_printf, char * const settings[],
               char * const user_info[], char * const user_env[],
               char * const plugin_options[], const char **errstr);

           Returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error.  In the latter case, sudo will
           print a usage message before it exits.  If an error occurs, the
           plugin may optionally call the conversation() or
           sudo_plugin_printf() function with SUDO_CONF_ERROR_MSG to present
           additional error information to the user.

           The function arguments are as follows:

           version
                 The version passed in by sudo allows the plugin to determine
                 the major and minor version number of the plugin API
                 supported by sudo.

           conversation
                 A pointer to the conversation() function that can be used by
                 the plugin to interact with the user (see Conversation API
                 for details).  Returns 0 on success and -1 on failure.

           sudo_plugin_printf
                 A pointer to a printf()-style function that may be used to
                 display informational or error messages (see Conversation API
                 for details).  Returns the number of characters printed on
                 success and -1 on failure.

           settings
                 A vector of user-supplied sudo settings in the form of
                 "name=value" strings.  The vector is terminated by a NULL
                 pointer.  These settings correspond to options the user
                 specified when running sudo.  As such, they will only be
                 present when the corresponding option has been specified on
                 the command line.

                 When parsing settings, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 The following values may be set by sudo:

                 bsdauth_type=string
                       Authentication type, if specified by the -a option, to
                       use on systems where BSD authentication is supported.

                 closefrom=number
                       If specified, the user has requested via the -C option
                       that sudo close all files descriptors with a value of
                       number or higher.  The plugin may optionally pass this,
                       or another value, back in the command_info list.

                 cmnd_chroot=string
                       The root directory (see chroot(2)) to run the command
                       in, as specified by the user via the -R option.  The
                       plugin may ignore or restrict the user's ability to
                       specify a new root directory.  Only available starting
                       with API version 1.16.

                 cmnd_cwd=string
                       The working directory to run the command in, as
                       specified by the user via the -D option.  The plugin
                       may ignore or restrict the user's ability to specify a
                       new working directory.  Only available starting with
                       API version 1.16.

                 debug_flags=string
                       A debug file path name followed by a space and a comma-
                       separated list of debug flags that correspond to the
                       plugin's Debug entry in sudo.conf(5), if there is one.
                       The flags are passed to the plugin exactly as they
                       appear in sudo.conf(5).  The syntax used by sudo and
                       the sudoers plugin is subsystem@priority but a plugin
                       is free to use a different format so long as it does
                       not include a comma (`,').  Prior to sudo 1.8.12, there
                       was no way to specify plugin-specific debug_flags so
                       the value was always the same as that used by the sudo
                       front-end and did not include a path name, only the
                       flags themselves.  As of version 1.7 of the plugin
                       interface, sudo will only pass debug_flags if
                       sudo.conf(5) contains a plugin-specific Debug entry.

                 ignore_ticket=bool
                       Set to true if the user specified the -k option along
                       with a command, indicating that the user wishes to
                       ignore any cached authentication credentials.
                       implied_shell to true.  This allows sudo with no
                       arguments to be used similarly to su(1).  If the plugin
                       does not to support this usage, it may return a value
                       of -2 from the check_policy() function, which will
                       cause sudo to print a usage message and exit.

                 implied_shell=bool
                       If the user does not specify a program on the command
                       line, sudo will pass the plugin the path to the user's
                       shell and set implied_shell.

                 intercept_ptrace=bool
                       Indicates whether or not the system supports intercept
                       mode using ptrace(2).  This is currently only true for
                       Linux systems that support seccomp(2) filtering and the
                       "trap" action.  Other systems will use a dynamic shared
                       object to implement intercept.  Only available starting
                       with API version 1.19.

                 intercept_setid=bool
                       Indicates whether or not the system supports running
                       set-user-ID and set-group-ID binaries in intercept
                       mode.  This is currently only true for Linux systems
                       that support seccomp(2) filtering and the "trap"
                       action.  On systems that use a dynamic shared object to
                       implement intercept, the dynamic linker (ld.so or the
                       equivalent) will disable preloading of shared objects
                       when executing a set-user-ID or set-group-ID binary.
                       This will disable intercept mode for that program and
                       any other programs that it executes.  The policy plugin
                       may refuse to execute a set-user-ID or set-group-ID
                       binary in intercept mode to avoid this.  Only available
                       starting with API version 1.19.

                 login_class=string
                       BSD login class to use when setting resource limits and
                       nice value, if specified by the -c option.

                 login_shell=bool
                       Set to true if the user specified the -i option,
                       indicating that the user wishes to run a login shell.

                 max_groups=int
                       The maximum number of groups a user may belong to.
                       This will only be present if there is a corresponding
                       setting in sudo.conf(5).

                 network_addrs=list
                       A space-separated list of IP network addresses and
                       netmasks in the form "addr/netmask", e.g.,
                       "192.168.1.2/255.255.255.0".  The address and netmask
                       pairs may be either IPv4 or IPv6, depending on what the
                       operating system supports.  If the address contains a
                       colon (`:'), it is an IPv6 address, else it is IPv4.

                 noninteractive=bool
                       Set to true if the user specified the -n option,
                       indicating that sudo should operate in non-interactive
                       mode.  The plugin may reject a command run in non-
                       interactive mode if user interaction is required.

                 plugin_dir=string
                       The default plugin directory used by the sudo front-
                       end.  This is the default directory set at compile time
                       and may not correspond to the directory the running
                       plugin was loaded from.  It may be used by a plugin to
                       locate support files.

                 plugin_path=string
                       The path name of plugin loaded by the sudo front-end.
                       The path name will be a fully-qualified unless the
                       plugin was statically compiled into sudo.

                 preserve_environment=bool
                       Set to true if the user specified the -E option,
                       indicating that the user wishes to preserve the
                       environment.

                 preserve_groups=bool
                       Set to true if the user specified the -P option,
                       indicating that the user wishes to preserve the group
                       vector instead of setting it based on the runas user.

                 progname=string
                       The command name that sudo was run as, typically "sudo"
                       or "sudoedit".

                 prompt=string
                       The prompt to use when requesting a password, if
                       specified via the -p option.

                 remote_host=string
                       The name of the remote host to run the command on, if
                       specified via the -h option.  Support for running the
                       command on a remote host is meant to be implemented via
                       a helper program that is executed in place of the user-
                       specified command.  The sudo front-end is only capable
                       of executing commands on the local host.  Only
                       available starting with API version 1.4.

                 run_shell=bool
                       Set to true if the user specified the -s option,
                       indicating that the user wishes to run a shell.

                 runas_group=string
                       The group name or group-ID to run the command as, if
                       specified via the -g option.

                 runas_user=string
                       The user name or user-ID to run the command as, if
                       specified via the -u option.

                 selinux_role=string
                       SELinux role to use when executing the command, if
                       specified by the -r option.

                 selinux_type=string
                       SELinux type to use when executing the command, if
                       specified by the -t option.

                 set_home=bool
                       Set to true if the user specified the -H option.  If
                       true, set the HOME environment variable to the target
                       user's home directory.

                 sudoedit=bool
                       Set to true when the -e option is specified or if
                       invoked as sudoedit.  The plugin shall substitute an
                       editor into argv in the check_policy() function or
                       return -2 with a usage error if the plugin does not
                       support sudoedit.  For more information, see the
                       check_policy() section.

                 timeout=string
                       Command timeout specified by the user via the -T
                       option.  Not all plugins support command timeouts and
                       the ability of the user to set a timeout may be
                       restricted by policy.  The format of the timeout string
                       is plugin-specific.

                 update_ticket=bool
                       Set to false if the user specified the -N option,
                       indicating that the user wishes to avoid updating any
                       cached authentication credentials.  Only available
                       starting with API version 1.20.

                 Additional settings may be added in the future so the plugin
                 should silently ignore settings that it does not recognize.

           user_info
                 A vector of information about the user running the command in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing user_info, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 The following values may be set by sudo:

                 cols=int
                       The number of columns the user's terminal supports.  If
                       there is no terminal device available, a default value
                       of 80 is used.

                 cwd=string
                       The user's current working directory.

                 egid=gid_t
                       The effective group-ID of the user invoking sudo.

                 euid=uid_t
                       The effective user-ID of the user invoking sudo.

                 gid=gid_t
                       The real group-ID of the user invoking sudo.

                 groups=list
                       The user's supplementary group list formatted as a
                       string of comma-separated group-IDs.

                 host=string
                       The local machine's hostname as returned by the
                       gethostname(2) system call.

                 lines=int
                       The number of lines the user's terminal supports.  If
                       there is no terminal device available, a default value
                       of 24 is used.

                 pgid=int
                       The ID of the process group that the running sudo
                       process is a member of.  Only available starting with
                       API version 1.2.

                 pid=int
                       The process ID of the running sudo process.  Only
                       available starting with API version 1.2.

                 ppid=int
                       The parent process ID of the running sudo process.
                       Only available starting with API version 1.2.

                 rlimit_as=soft,hard
                       The maximum size to which the process's address space
                       may grow (in bytes), if supported by the operating
                       system.  The soft and hard limits are separated by a
                       comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 rlimit_core=soft,hard
                       The largest size core dump file that may be created (in
                       bytes).  The soft and hard limits are separated by a
                       comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 rlimit_cpu=soft,hard
                       The maximum amount of CPU time that the process may use
                       (in seconds).  The soft and hard limits are separated
                       by a comma.  A value of "infinity" indicates that there
                       is no limit.  Only available starting with API version
                       1.16.

                 rlimit_data=soft,hard
                       The maximum size of the data segment for the process
                       (in bytes).  The soft and hard limits are separated by
                       a comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 rlimit_fsize=soft,hard
                       The largest size file that the process may create (in
                       bytes).  The soft and hard limits are separated by a
                       comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 rlimit_locks=soft,hard
                       The maximum number of locks that the process may
                       establish, if supported by the operating system.  The
                       soft and hard limits are separated by a comma.  A value
                       of "infinity" indicates that there is no limit.  Only
                       available starting with API version 1.16.

                 rlimit_memlock=soft,hard
                       The maximum size that the process may lock in memory
                       (in bytes), if supported by the operating system.  The
                       soft and hard limits are separated by a comma.  A value
                       of "infinity" indicates that there is no limit.  Only
                       available starting with API version 1.16.

                 rlimit_nofile=soft,hard
                       The maximum number of files that the process may have
                       open.  The soft and hard limits are separated by a
                       comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 rlimit_nproc=soft,hard
                       The maximum number of processes that the user may run
                       simultaneously.  The soft and hard limits are separated
                       by a comma.  A value of "infinity" indicates that there
                       is no limit.  Only available starting with API version
                       1.16.

                 rlimit_rss=soft,hard
                       The maximum size to which the process's resident set
                       size may grow (in bytes).  The soft and hard limits are
                       separated by a comma.  A value of "infinity" indicates
                       that there is no limit.  Only available starting with
                       API version 1.16.

                 rlimit_stack=soft,hard
                       The maximum size to which the process's stack may grow
                       (in bytes).  The soft and hard limits are separated by
                       a comma.  A value of "infinity" indicates that there is
                       no limit.  Only available starting with API version
                       1.16.

                 sid=int
                       The session ID of the running sudo process or 0 if sudo
                       is not part of a POSIX job control session.  Only
                       available starting with API version 1.2.

                 tcpgid=int
                       The ID of the foreground process group associated with
                       the terminal device associated with the sudo process or
                       0 if there is no terminal present.  Only available
                       starting with API version 1.2.

                 tty=string
                       The path to the user's terminal device.  If the user
                       has no terminal device associated with the session, the
                       value will be empty, as in `tty='.

                 uid=uid_t
                       The real user-ID of the user invoking sudo.

                 umask=octal
                       The invoking user's file creation mask.  Only available
                       starting with API version 1.10.

                 user=string
                       The name of the user invoking sudo.

           user_env
                 The user's environment in the form of a NULL-terminated
                 vector of "name=value" strings.

                 When parsing user_env, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

           plugin_options
                 Any (non-comment) strings immediately after the plugin path
                 are passed as arguments to the plugin.  These arguments are
                 split on a white space boundary and are passed to the plugin
                 in the form of a NULL-terminated array of strings.  If no
                 arguments were specified, plugin_options will be the NULL
                 pointer.

                 The plugin_options parameter is only available starting with
                 API version 1.2.  A plugin must check the API version
                 specified by the sudo front-end before using plugin_options.
                 Failure to do so may result in a crash.

           errstr
                 If the open() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     close
           void (*close)(int exit_status, int error);

           The close() function is called when sudo is finished, shortly
           before it exits.  Starting with API version 1.15, close() is called
           regardless of whether or not a command was actually executed.  This
           makes it possible for plugins to perform cleanup even when a
           command was not run.  It is not possible to tell whether a command
           was run based solely on the arguments passed to the close()
           function.  To determine if a command was actually run, the plugin
           must keep track of whether or not the check_policy() function
           returned successfully.

           The function arguments are as follows:

           exit_status
                 The command's exit status, as returned by the wait(2) system
                 call, or zero if no command was run.  The value of
                 exit_status is undefined if error is non-zero.

           error
                 If the command could not be executed, this is set to the
                 value of errno set by the execve(2) system call.  The plugin
                 is responsible for displaying error information via the
                 conversation() or sudo_plugin_printf() function.  If the
                 command was successfully executed, the value of error is
                 zero.

           If no close() function is defined, no I/O logging plugins are
           loaded, and neither the timeout nor use_pty options are set in the
           command_info list, the sudo front-end may execute the command
           directly instead of running it as a child process.

     show_version
           int (*show_version)(int verbose);

           The show_version() function is called by sudo when the user
           specifies the -V option.  The plugin may display its version
           information to the user via the conversation() or
           sudo_plugin_printf() function using SUDO_CONV_INFO_MSG.  If the
           user requests detailed version information, the verbose flag will
           be non-zero.

           Returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error, although the return value is
           currently ignored.

     check_policy
           int (*check_policy)(int argc, char * const argv[], char *env_add[],
               char **command_info[], char **argv_out[], char **user_env_out[],
               const char **errstr);

           The check_policy() function is called by sudo to determine whether
           the user is allowed to run the specified commands.

           If the sudoedit option was enabled in the settings array passed to
           the open() function, the user has requested sudoedit mode.
           sudoedit is a mechanism for editing one or more files where an
           editor is run with the user's credentials instead of with elevated
           privileges.  sudo achieves this by creating user-writable temporary
           copies of the files to be edited and then overwriting the originals
           with the temporary copies after editing is complete.  If the plugin
           supports sudoedit, it must set sudoedit=true in the command_info
           list.  The plugin is responsible for choosing the editor to be
           used, potentially from a variable in the user's environment, such
           as EDITOR, and should be stored in argv_out (environment variables
           may include command line options).  The files to be edited should
           be copied from argv to argv_out, separated from the editor and its
           arguments by a `--' element.  The `--' will be removed by sudo
           before the editor is executed.  The plugin may also set
           sudoedit_nfiles to the number of files to be edited in the
           command_info list; this will only be used by the sudo front-end
           starting with API version 1.21.

           The check_policy() function returns 1 if the command is allowed, 0
           if not allowed, -1 for a general error, or -2 for a usage error or
           if sudoedit was specified but is unsupported by the plugin.  In the
           latter case, sudo will print a usage message before it exits.  If
           an error occurs, the plugin may optionally call the conversation()
           or sudo_plugin_printf() function with SUDO_CONF_ERROR_MSG to
           present additional error information to the user.

           The function arguments are as follows:

           argc  The number of elements in argv, not counting the final NULL
                 pointer.

           argv  The argument vector describing the command the user wishes to
                 run, in the same form as what would be passed to the
                 execve(2) system call.  The vector is terminated by a NULL
                 pointer.

           env_add
                 Additional environment variables specified by the user on the
                 command line in the form of a NULL-terminated vector of
                 "name=value" strings.  The plugin may reject the command if
                 one or more variables are not allowed to be set, or it may
                 silently ignore such variables.

                 When parsing env_add, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

           command_info
                 Information about the command being run in the form of
                 "name=value" strings.  These values are used by sudo to set
                 the execution environment when running a command.  The plugin
                 is responsible for creating and populating the vector, which
                 must be terminated with a NULL pointer.  The following values
                 are recognized by sudo:

                 apparmor_profile=string
                       AppArmor profile to transition to when executing the
                       command.  Only available starting with API version
                       1.19.

                 chroot=string
                       The root directory to use when running the command.

                 closefrom=number
                       If specified, sudo will close all files descriptors
                       with a value of number or higher.

                 command=string
                       Fully qualified path to the command to be executed.

                 cwd=string
                       The current working directory to change to when
                       executing the command.  If sudo is unable to change to
                       the new working directory, the command will not be run
                       unless cwd_optional is also set (see below).

                 cwd_optional=bool
                       If set, sudo will treat an inability to change to the
                       new working directory as a non-fatal error.  This
                       setting has no effect unless cwd is also set.

                 exec_background=bool
                       By default, sudo runs a command as the foreground
                       process as long as sudo itself is running in the
                       foreground.  When exec_background is enabled and the
                       command is being run in a pseudo-terminal (due to I/O
                       logging or the use_pty setting), the command will be
                       run as a background process.  Attempts to read from the
                       controlling terminal (or to change terminal settings)
                       will result in the command being suspended with the
                       SIGTTIN signal (or SIGTTOU in the case of terminal
                       settings).  If this happens when sudo is a foreground
                       process, the command will be granted the controlling
                       terminal and resumed in the foreground with no user
                       intervention required.  The advantage of initially
                       running the command in the background is that sudo need
                       not read from the terminal unless the command
                       explicitly requests it.  Otherwise, any terminal input
                       must be passed to the command, whether it has required
                       it or not (the kernel buffers terminals so it is not
                       possible to tell whether the command really wants the
                       input).  This is different from historic sudo behavior
                       or when the command is not being run in a pseudo-
                       terminal.

                       For this to work seamlessly, the operating system must
                       support the automatic restarting of system calls.
                       Unfortunately, not all operating systems do this by
                       default, and even those that do may have bugs.  For
                       example, macOS fails to restart the tcgetattr() and
                       tcsetattr() system calls (this is a bug in macOS).
                       Furthermore, because this behavior depends on the
                       command stopping with the SIGTTIN or SIGTTOU signals,
                       programs that catch these signals and suspend
                       themselves with a different signal (usually SIGTOP)
                       will not be automatically foregrounded.  Some versions
                       of the linux su(1) command behave this way.  Because of
                       this, a plugin should not set exec_background unless it
                       is explicitly enabled by the administrator and there
                       should be a way to enabled or disable it on a per-
                       command basis.

                       This setting has no effect unless I/O logging is
                       enabled or use_pty is enabled.

                 execfd=number
                       If specified, sudo will use the fexecve(2) system call
                       to execute the command instead of execve(2).  The
                       specified number must refer to an open file descriptor.

                 intercept=bool
                       If set, sudo will intercept attempts to execute a
                       subsequent command and perform a policy check via the
                       policy plugin's check_policy() function to determine
                       whether or not the command is permitted.  This can be
                       used to prevent shell escapes on supported platforms
                       but it has a number of limitations.  See Preventing
                       shell escapes in sudoers(5) for details.  Only
                       available starting with API version 1.18.

                 intercept_verify=bool
                       If set, sudo will attempt to verify that a command run
                       in intercept mode has the expected path name, command
                       line arguments and environment.  This setting has no
                       effect unless use_ptrace is also enabled.  Only
                       available starting with API version 1.20.

                 iolog_compress=bool
                       Set to true if the I/O logging plugins, if any, should
                       compress the log data.  This is a hint to the I/O
                       logging plugin which may choose to ignore it.

                 iolog_group=string
                       The group that will own newly created I/O log files and
                       directories.  This is a hint to the I/O logging plugin
                       which may choose to ignore it.

                 iolog_mode=octal
                       The file permission mode to use when creating I/O log
                       files and directories.  This is a hint to the I/O
                       logging plugin which may choose to ignore it.

                 iolog_user=string
                       The user that will own newly created I/O log files and
                       directories.  This is a hint to the I/O logging plugin
                       which may choose to ignore it.

                 iolog_path=string
                       Fully qualified path to the file or directory in which
                       I/O log is to be stored.  This is a hint to the I/O
                       logging plugin which may choose to ignore it.  If no
                       I/O logging plugin is loaded, this setting has no
                       effect.

                 iolog_stdin=bool
                       Set to true if the I/O logging plugins, if any, should
                       log the standard input if it is not connected to a
                       terminal device.  This is a hint to the I/O logging
                       plugin which may choose to ignore it.

                 iolog_stdout=bool
                       Set to true if the I/O logging plugins, if any, should
                       log the standard output if it is not connected to a
                       terminal device.  This is a hint to the I/O logging
                       plugin which may choose to ignore it.

                 iolog_stderr=bool
                       Set to true if the I/O logging plugins, if any, should
                       log the standard error if it is not connected to a
                       terminal device.  This is a hint to the I/O logging
                       plugin which may choose to ignore it.

                 iolog_ttyin=bool
                       Set to true if the I/O logging plugins, if any, should
                       log all terminal input.  This only includes input typed
                       by the user and not from a pipe or redirected from a
                       file.  This is a hint to the I/O logging plugin which
                       may choose to ignore it.

                 iolog_ttyout=bool
                       Set to true if the I/O logging plugins, if any, should
                       log all terminal output.  This only includes output to
                       the screen, not output to a pipe or file.  This is a
                       hint to the I/O logging plugin which may choose to
                       ignore it.

                 login_class=string
                       BSD login class to use when setting resource limits and
                       nice value (optional).  This option is only set on
                       systems that support login classes.

                 nice=int
                       Nice value (priority) to use when executing the
                       command.  The nice value, if specified, overrides the
                       priority associated with the login_class on BSD
                       systems.

                 log_subcmds=bool
                       If set, sudo will call the audit plugin's accept()
                       function to log when the command runs a subsequent
                       command, if supported by the system.  If intercept is
                       also specified, log_subcmds will be ignored.  See
                       Preventing shell escapes in sudoers(5) for more
                       information.  Only available starting with API version
                       1.18.

                 noexec=bool
                       If set, prevent the command from executing other
                       programs.

                 preserve_fds=list
                       A comma-separated list of file descriptors that should
                       be preserved, regardless of the value of the closefrom
                       setting.  Only available starting with API version 1.5.

                 preserve_groups=bool
                       If set, sudo will preserve the user's group vector
                       instead of initializing the group vector based on
                       runas_user.

                 rlimit_as=soft,hard
                       The maximum size to which the process's address space
                       may grow (in bytes), if supported by the operating
                       system.  The soft and hard limits are separated by a
                       comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 rlimit_core=soft,hard
                       The largest size core dump file that may be created (in
                       bytes).  The soft and hard limits are separated by a
                       comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 rlimit_cpu=soft,hard
                       The maximum amount of CPU time that the process may use
                       (in seconds).  The soft and hard limits are separated
                       by a comma.  If only a single value is specified, both
                       the hard and soft limits are set.  A value of
                       "infinity" indicates that there is no limit.  A value
                       of "user" will cause the invoking user's resource limit
                       to be preserved.  A value of "default" will cause the
                       target user's default resource limit to be used on
                       systems that allow per-user resource limits to be
                       configured.  Only available starting with API version
                       1.18.

                 rlimit_data=soft,hard
                       The maximum size of the data segment for the process
                       (in bytes).  The soft and hard limits are separated by
                       a comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 rlimit_fsize=soft,hard
                       The largest size file that the process may create (in
                       bytes).  The soft and hard limits are separated by a
                       comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 rlimit_locks=soft,hard
                       The maximum number of locks that the process may
                       establish, if supported by the operating system.  The
                       soft and hard limits are separated by a comma.  If only
                       a single value is specified, both the hard and soft
                       limits are set.  A value of "infinity" indicates that
                       there is no limit.  A value of "user" will cause the
                       invoking user's resource limit to be preserved.  A
                       value of "default" will cause the target user's default
                       resource limit to be used on systems that allow per-
                       user resource limits to be configured.  Only available
                       starting with API version 1.18.

                 rlimit_memlock=soft,hard
                       The maximum size that the process may lock in memory
                       (in bytes), if supported by the operating system.  The
                       soft and hard limits are separated by a comma.  If only
                       a single value is specified, both the hard and soft
                       limits are set.  A value of "infinity" indicates that
                       there is no limit.  A value of "user" will cause the
                       invoking user's resource limit to be preserved.  A
                       value of "default" will cause the target user's default
                       resource limit to be used on systems that allow per-
                       user resource limits to be configured.  Only available
                       starting with API version 1.18.

                 rlimit_nofile=soft,hard
                       The maximum number of files that the process may have
                       open.  The soft and hard limits are separated by a
                       comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 rlimit_nproc=soft,hard
                       The maximum number of processes that the user may run
                       simultaneously.  The soft and hard limits are separated
                       by a comma.  If only a single value is specified, both
                       the hard and soft limits are set.  A value of
                       "infinity" indicates that there is no limit.  A value
                       of "user" will cause the invoking user's resource limit
                       to be preserved.  A value of "default" will cause the
                       target user's default resource limit to be used on
                       systems that allow per-user resource limits to be
                       configured.  Only available starting with API version
                       1.18.

                 rlimit_rss=soft,hard
                       The maximum size to which the process's resident set
                       size may grow (in bytes).  The soft and hard limits are
                       separated by a comma.  If only a single value is
                       specified, both the hard and soft limits are set.  A
                       value of "infinity" indicates that there is no limit.
                       A value of "user" will cause the invoking user's
                       resource limit to be preserved.  A value of "default"
                       will cause the target user's default resource limit to
                       be used on systems that allow per-user resource limits
                       to be configured.  Only available starting with API
                       version 1.18.

                 rlimit_stack=soft,hard
                       The maximum size to which the process's stack may grow
                       (in bytes).  The soft and hard limits are separated by
                       a comma.  If only a single value is specified, both the
                       hard and soft limits are set.  A value of "infinity"
                       indicates that there is no limit.  A value of "user"
                       will cause the invoking user's resource limit to be
                       preserved.  A value of "default" will cause the target
                       user's default resource limit to be used on systems
                       that allow per-user resource limits to be configured.
                       Only available starting with API version 1.18.

                 runas_egid=gid
                       Effective group-ID to run the command as.  If not
                       specified, the value of runas_gid is used.

                 runas_euid=uid
                       Effective user-ID to run the command as.  If not
                       specified, the value of runas_uid is used.

                 runas_gid=gid
                       Group-ID to run the command as.

                 runas_group=string
                       The name of the group the command will run as, if it is
                       different from the runas_user's default group.  This
                       value is provided for auditing purposes only, the sudo
                       front-end uses runas_egid and runas_gid when executing
                       the command.

                 runas_groups=list
                       The supplementary group vector to use for the command
                       in the form of a comma-separated list of group-IDs.  If
                       preserve_groups is set, this option is ignored.

                 runas_uid=uid
                       User-ID to run the command as.

                 runas_user=string
                       The name of the user the command will run as, which
                       should correspond to runas_euid (or runas_uid if
                       runas_euid is not set).  This value is provided for
                       auditing purposes only, the sudo front-end uses
                       runas_euid and runas_uid when executing the command.

                 selinux_role=string
                       SELinux role to use when executing the command.

                 selinux_type=string
                       SELinux type to use when executing the command.

                 set_utmp=bool
                       Create a utmp (or utmpx) entry when a pseudo-terminal
                       is allocated.  By default, the new entry will be a copy
                       of the user's existing utmp entry (if any), with the
                       tty, time, type, and pid fields updated.

                 sudoedit=bool
                       Set to true when in sudoedit mode.  The plugin may
                       enable sudoedit mode even if sudo was not invoked as
                       sudoedit.  This allows the plugin to perform command
                       substitution and transparently enable sudoedit when the
                       user attempts to run an editor.

                 sudoedit_checkdir=bool
                       Set to false to disable directory writability checks in
                       sudoedit.  By default, sudoedit 1.8.16 and higher will
                       check all directory components of the path to be edited
                       for writability by the invoking user.  Symbolic links
                       will not be followed in writable directories and
                       sudoedit will refuse to edit a file located in a
                       writable directory.  These restrictions are not
                       enforced when sudoedit is run by root.  The
                       sudoedit_checkdir option can be set to false to disable
                       this check.  Only available starting with API version
                       1.8.

                 sudoedit_follow=bool
                       Set to true to allow sudoedit to edit files that are
                       symbolic links.  By default, sudoedit 1.8.15 and higher
                       will refuse to open a symbolic link.  The
                       sudoedit_follow option can be used to restore the older
                       behavior and allow sudoedit to open symbolic links.
                       Only available starting with API version 1.8.

                 sudoedit_nfiles=number
                       The number of files to be edited by the user.  If
                       present, this is will be used by the sudo front-end to
                       determine which elements of the argv_out vector are
                       files to be edited.  The `--' element must immediately
                       precede the first file to be editied.  If
                       sudoedit_nfiles is not specified, the sudo front-end
                       will use the position of the `--' element to determine
                       where the file list begins.  Only available starting
                       with API version 1.21.

                 timeout=int
                       Command timeout.  If non-zero then when the timeout
                       expires the command will be killed.

                 umask=octal
                       The file creation mask to use when executing the
                       command.  This value may be overridden by PAM or
                       login.conf on some systems unless the umask_override
                       option is also set.

                 umask_override=bool
                       Force the value specified by the umask option to
                       override any umask set by PAM or login.conf.

                 use_ptrace=bool
                       If set, sudo will use ptrace(2) to implement intercept
                       mode if supported by the system.  This setting has no
                       effect unless intercept is also set.  Only available
                       starting with API version 1.19.

                 use_pty=bool
                       Allocate a pseudo-terminal to run the command in,
                       regardless of whether or not I/O logging is in use.  By
                       default, sudo will only run the command in a pseudo-
                       terminal when an I/O log plugin is loaded.

                 utmp_user=string
                       User name to use when constructing a new utmp (or
                       utmpx) entry when set_utmp is enabled.  This option can
                       be used to set the user field in the utmp entry to the
                       user the command runs as rather than the invoking user.
                       If not set, sudo will base the new entry on the
                       invoking user's existing entry.

                 Unsupported values will be ignored.

           argv_out
                 The NULL-terminated argument vector to pass to the execve(2)
                 system call when executing the command.  The plugin is
                 responsible for allocating and populating the vector.

           user_env_out
                 The NULL-terminated environment vector to use when executing
                 the command.  The plugin is responsible for allocating and
                 populating the vector.

           errstr
                 If the check_policy() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     list
           int (*list)(int argc, char * const argv[], int verbose,
               const char *user, const char **errstr);

           List available privileges for the invoking user.  Returns 1 on
           success, 0 on failure, and -1 on error.  On error, the plugin may
           optionally call the conversation() or sudo_plugin_printf() function
           with SUDO_CONF_ERROR_MSG to present additional error information to
           the user.

           Privileges should be output via the conversation() or
           sudo_plugin_printf() function using SUDO_CONV_INFO_MSG.

           The function arguments are as follows:

           argc  The number of elements in argv, not counting the final NULL
                 pointer.

           argv  If non-NULL, an argument vector describing a command the user
                 wishes to check against the policy in the same form as what
                 would be passed to the execve(2) system call.  If the command
                 is permitted by the policy, the fully-qualified path to the
                 command should be displayed along with any command line
                 arguments.

           verbose
                 Flag indicating whether to list in verbose mode or not.

           user  The name of a different user to list privileges for if the
                 policy allows it.  If NULL, the plugin should list the
                 privileges of the invoking user.

           errstr
                 If the list() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     validate
           int (*validate)(const char **errstr);

           The validate() function is called when sudo is run with the -v
           option.  For policy plugins such as sudoers that cache
           authentication credentials, this function will validate and cache
           the credentials.

           The validate() function should be NULL if the plugin does not
           support credential caching.

           Returns 1 on success, 0 on failure, and -1 on error.  On error, the
           plugin may optionally call the conversation() or
           sudo_plugin_printf() function with SUDO_CONF_ERROR_MSG to present
           additional error information to the user.

           The function arguments are as follows:

           errstr
                 If the validate() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     invalidate
           void (*invalidate)(int rmcred);

           The invalidate() function is called when sudo is run with the -k or
           -K option.  For policy plugins such as sudoers that cache
           authentication credentials, this function will invalidate the
           credentials.  If the rmcred flag is non-zero, the plugin may remove
           the credentials instead of simply invalidating them.

           The invalidate() function should be NULL if the plugin does not
           support credential caching.

     init_session
           int (*init_session)(struct passwd *pwd, char **user_env[],
               const char **errstr);

           The init_session() function is called before sudo sets up the
           execution environment for the command.  It is run in the parent
           sudo process before any user-ID or group-ID changes.  This can be
           used to perform session setup that is not supported by
           command_info, such as opening the PAM session.  The close()
           function can be used to tear down the session that was opened by
           init_session().

           Returns 1 on success, 0 on failure, and -1 on error.  On error, the
           plugin may optionally call the conversation() or
           sudo_plugin_printf() function with SUDO_CONF_ERROR_MSG to present
           additional error information to the user.

           The function arguments are as follows:

           pwd   If the user-ID the command will run as was found in the
                 password database, pwd will describe that user, otherwise it
                 will be NULL.

           user_env_out
                 The NULL-terminated environment vector to use when executing
                 the command.  This is the same string passed back to the
                 front-end via the Policy Plugin's user_env_out parameter.  If
                 the init_session() function needs to modify the user
                 environment, it should update the pointer stored in
                 user_env_out.  The expected use case is to merge the contents
                 of the PAM environment (if any) with the contents of
                 user_env_out.  The user_env_out parameter is only available
                 starting with API version 1.2.  A plugin must check the API
                 version specified by the sudo front-end before using
                 user_env_out.  Failure to do so may result in a crash.

           errstr
                 If the init_session() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     register_hooks
           void (*register_hooks)(int version,
              int (*register_hook)(struct sudo_hook *hook));

           The register_hooks() function is called by the sudo front-end to
           register any hooks the plugin needs.  If the plugin does not
           support hooks, register_hooks should be set to the NULL pointer.

           The version argument describes the version of the hooks API
           supported by the sudo front-end.

           The register_hook() function should be used to register any
           supported hooks the plugin needs.  It returns 0 on success, 1 if
           the hook type is not supported, and -1 if the major version in
           struct sudo_hook does not match the front-end's major hook API
           version.

           See the Hook function API section below for more information about
           hooks.

           The register_hooks() function is only available starting with API
           version 1.2.  If the sudo front-end doesn't support API version 1.2
           or higher, register_hooks() will not be called.

     deregister_hooks
           void (*deregister_hooks)(int version,
              int (*deregister_hook)(struct sudo_hook *hook));

           The deregister_hooks() function is called by the sudo front-end to
           deregister any hooks the plugin has registered.  If the plugin does
           not support hooks, deregister_hooks should be set to the NULL
           pointer.

           The version argument describes the version of the hooks API
           supported by the sudo front-end.

           The deregister_hook() function should be used to deregister any
           hooks that were put in place by the register_hook() function.  If
           the plugin tries to deregister a hook that the front-end does not
           support, deregister_hook() will return an error.

           See the Hook function API section below for more information about
           hooks.

           The deregister_hooks() function is only available starting with API
           version 1.2.  If the sudo front-end doesn't support API version 1.2
           or higher, deregister_hooks() will not be called.

     event_alloc
           struct sudo_plugin_event * (*event_alloc)(void);

           The event_alloc() function is used to allocate a struct
           sudo_plugin_event which provides access to the main sudo event
           loop.  Unlike the other fields, the event_alloc pointer is filled
           in by the sudo front-end, not by the plugin.

           See the Event API section below for more information about events.

           The event_alloc() function is only available starting with API
           version 1.15.  If the sudo front-end doesn't support API version
           1.15 or higher, event_alloc will not be set.

     Policy Plugin Version Macros

     /* Plugin API version major/minor. */
     #define SUDO_API_VERSION_MAJOR 1
     #define SUDO_API_VERSION_MINOR 13
     #define SUDO_API_MKVERSION(x, y) ((x << 16) | y)
     #define SUDO_API_VERSION SUDO_API_MKVERSION(SUDO_API_VERSION_MAJOR,\
                                                 SUDO_API_VERSION_MINOR)

     /* Getters and setters for API version */
     #define SUDO_API_VERSION_GET_MAJOR(v) ((v) >> 16)
     #define SUDO_API_VERSION_GET_MINOR(v) ((v) & 0xffff)
     #define SUDO_API_VERSION_SET_MAJOR(vp, n) do { \
         *(vp) = (*(vp) & 0x0000ffff) | ((n) << 16); \
     } while(0)
     #define SUDO_API_VERSION_SET_MINOR(vp, n) do { \
         *(vp) = (*(vp) & 0xffff0000) | (n); \
     } while(0)

   I/O plugin API
     struct io_plugin {
     #define SUDO_IO_PLUGIN 2
         unsigned int type; /* always SUDO_IO_PLUGIN */
         unsigned int version; /* always SUDO_API_VERSION */
         int (*open)(unsigned int version, sudo_conv_t conversation,
             sudo_printf_t sudo_plugin_printf, char * const settings[],
             char * const user_info[], char * const command_info[],
             int argc, char * const argv[], char * const user_env[],
             char * const plugin_options[], const char **errstr);
         void (*close)(int exit_status, int error); /* wait status or error */
         int (*show_version)(int verbose);
         int (*log_ttyin)(const char *buf, unsigned int len,
             const char **errstr);
         int (*log_ttyout)(const char *buf, unsigned int len,
             const char **errstr);
         int (*log_stdin)(const char *buf, unsigned int len,
             const char **errstr);
         int (*log_stdout)(const char *buf, unsigned int len,
             const char **errstr);
         int (*log_stderr)(const char *buf, unsigned int len,
             const char **errstr);
         void (*register_hooks)(int version,
            int (*register_hook)(struct sudo_hook *hook));
         void (*deregister_hooks)(int version,
            int (*deregister_hook)(struct sudo_hook *hook));
         int (*change_winsize)(unsigned int lines, unsigned int cols,
             const char **errstr);
         int (*log_suspend)(int signo, const char **errstr);
         struct sudo_plugin_event * (*event_alloc)(void);
     };

     When an I/O plugin is loaded, sudo runs the command in a pseudo-terminal.
     This makes it possible to log the input and output from the user's
     session.  If any of the standard input, standard output, or standard
     error do not correspond to a tty, sudo will open a pipe to capture the
     I/O for logging before passing it on.

     The log_ttyin() function receives the raw user input from the terminal
     device (this will include input even when echo is disabled, such as when
     a password is read).  The log_ttyout() function receives output from the
     pseudo-terminal that is suitable for replaying the user's session at a
     later time.  The log_stdin(), log_stdout(), and log_stderr() functions
     are only called if the standard input, standard output, or standard error
     respectively correspond to something other than a tty.

     Any of the logging functions may be set to the NULL pointer if no logging
     is to be performed.  If the open function returns 0, no I/O will be sent
     to the plugin.

     If a logging function returns an error (-1), 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.

     If an input logging function rejects the data by returning 0, 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 0, 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.

     A struct audit_plugin has the following fields:

     type  The type field should always be set to SUDO_IO_PLUGIN.

     version
           The version field should be set to SUDO_API_VERSION.

           This allows sudo to determine the API version the plugin was built
           against.

     open
           int (*open)(unsigned int version, sudo_conv_t conversation,
               sudo_printf_t sudo_plugin_printf, char * const settings[],
               char * const user_info[], char * const command_info[],
               int argc, char * const argv[], char * const user_env[],
               char * const plugin_options[]);

           The open() function is run before the log_ttyin(), log_ttyout(),
           log_stdin(), log_stdout(), log_stderr(), log_suspend(),
           change_winsize(), or show_version() functions are called.  It is
           only called if the version is being requested or if the policy
           plugin's check_policy() function has returned successfully.  It
           returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error.  In the latter case, sudo will
           print a usage message before it exits.  If an error occurs, the
           plugin may optionally call the conversation() or
           sudo_plugin_printf() function with SUDO_CONF_ERROR_MSG to present
           additional error information to the user.

           The function arguments are as follows:

           version
                 The version passed in by sudo allows the plugin to determine
                 the major and minor version number of the plugin API
                 supported by sudo.

           conversation
                 A pointer to the conversation() function that may be used by
                 the Fa(show_version) function to display version information
                 (see show_version() below).  The conversation() function may
                 also be used to display additional error message to the user.
                 The conversation() function returns 0 on success and -1 on
                 failure.

           sudo_plugin_printf
                 A pointer to a printf()-style function that may be used by
                 the show_version() function to display version information
                 (see show_version below).  The sudo_plugin_printf() function
                 may also be used to display additional error message to the
                 user.  The sudo_plugin_printf() function returns number of
                 characters printed on success and -1 on failure.

           settings
                 A vector of user-supplied sudo settings in the form of
                 "name=value" strings.  The vector is terminated by a NULL
                 pointer.  These settings correspond to options the user
                 specified when running sudo.  As such, they will only be
                 present when the corresponding option has been specified on
                 the command line.

                 When parsing settings, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 settings.

           user_info
                 A vector of information about the user running the command in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing user_info, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           command_info
                 A vector of information describing the command being run in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing command_info, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           argc  The number of elements in argv, not counting the final NULL
                 pointer.  It can be zero, such as when sudo is called with
                 the -V option.

           argv  If non-NULL, an argument vector describing a command the user
                 wishes to run in the same form as what would be passed to the
                 execve(2) system call.

           user_env
                 The user's environment in the form of a NULL-terminated
                 vector of "name=value" strings.

                 When parsing user_env, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

           plugin_options
                 Any (non-comment) strings immediately after the plugin path
                 are treated as arguments to the plugin.  These arguments are
                 split on a white space boundary and are passed to the plugin
                 in the form of a NULL-terminated array of strings.  If no
                 arguments were specified, plugin_options will be the NULL
                 pointer.

                 The plugin_options parameter is only available starting with
                 API version 1.2.  A plugin must check the API version
                 specified by the sudo front-end before using plugin_options.
                 Failure to do so may result in a crash.

           errstr
                 If the open() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     close
           void (*close)(int exit_status, int error);

           The close() function is called when sudo is finished, shortly
           before it exits.

           The function arguments are as follows:

           exit_status
                 The command's exit status, as returned by the wait(2) system
                 call, or zero if no command was run.  The value of
                 exit_status is undefined if error is non-zero.

           error
                 If the command could not be executed, this is set to the
                 value of errno set by the execve(2) system call.  If the
                 command was successfully executed, the value of error is
                 zero.

     show_version
           int (*show_version)(int verbose);

           The show_version() function is called by sudo when the user
           specifies the -V option.  The plugin may display its version
           information to the user via the conversation() or
           sudo_plugin_printf() function using SUDO_CONV_INFO_MSG.  If the
           user requests detailed version information, the verbose flag will
           be non-zero.

           Returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error, although the return value is
           currently ignored.

     log_ttyin
           int (*log_ttyin)(const char *buf, unsigned int len,
               const char **errstr);

           The log_ttyin() function is called whenever data can be read from
           the user but before it is passed to the running command.  This
           allows the plugin to reject data if it chooses to (for instance if
           the input contains banned content).  Returns 1 if the data should
           be passed to the command, 0 if the data is rejected (which will
           terminate the running command), or -1 if an error occurred.

           The function arguments are as follows:

           buf   The buffer containing user input.

           len   The length of buf in bytes.

           errstr
                 If the log_ttyin() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     log_ttyout
           int (*log_ttyout)(const char *buf, unsigned int len,
               const char **errstr);

           The log_ttyout() function is called whenever data can be read from
           the command but before it is written to the user's terminal.  This
           allows the plugin to reject data if it chooses to (for instance if
           the output contains banned content).  Returns 1 if the data should
           be passed to the user, 0 if the data is rejected (which will
           terminate the running command), or -1 if an error occurred.

           The function arguments are as follows:

           buf   The buffer containing command output.

           len   The length of buf in bytes.

           errstr
                 If the log_ttyout() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     log_stdin
           int (*log_stdin)(const char *buf, unsigned int len,
               const char **errstr);

           The log_stdin() function is only used if the standard input does
           not correspond to a tty device.  It is called whenever data can be
           read from the standard input but before it is passed to the running
           command.  This allows the plugin to reject data if it chooses to
           (for instance if the input contains banned content).  Returns 1 if
           the data should be passed to the command, 0 if the data is rejected
           (which will terminate the running command), or -1 if an error
           occurred.

           The function arguments are as follows:

           buf   The buffer containing user input.

           len   The length of buf in bytes.

           errstr
                 If the log_stdin() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     log_stdout
           int (*log_stdout)(const char *buf, unsigned int len,
               const char **errstr);

           The log_stdout() function is only used if the standard output does
           not correspond to a tty device.  It is called whenever data can be
           read from the command but before it is written to the standard
           output.  This allows the plugin to reject data if it chooses to
           (for instance if the output contains banned content).  Returns 1 if
           the data should be passed to the user, 0 if the data is rejected
           (which will terminate the running command), or -1 if an error
           occurred.

           The function arguments are as follows:

           buf   The buffer containing command output.

           len   The length of buf in bytes.

           errstr
                 If the log_stdout() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     log_stderr
           int (*log_stderr)(const char *buf, unsigned int len,
               const char **errstr);

           The log_stderr() function is only used if the standard error does
           not correspond to a tty device.  It is called whenever data can be
           read from the command but before it is written to the standard
           error.  This allows the plugin to reject data if it chooses to (for
           instance if the output contains banned content).  Returns 1 if the
           data should be passed to the user, 0 if the data is rejected (which
           will terminate the running command), or -1 if an error occurred.

           The function arguments are as follows:

           buf   The buffer containing command output.

           len   The length of buf in bytes.

           errstr
                 If the log_stderr() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     register_hooks
           See the Policy plugin API section for a description of
           register_hooks().

     deregister_hooks
           See the Policy plugin API section for a description of
           deregister_hooks().

     change_winsize
           int (*change_winsize)(unsigned int lines, unsigned int cols,
               const char **errstr);

           The change_winsize() function is called whenever the window size of
           the terminal changes from the initial values specified in the
           user_info list.  Returns -1 if an error occurred, in which case no
           further calls to change_winsize() will be made,

           The function arguments are as follows:

           lines
                 The number of lines (rows) in the re-sized terminal.

           cols  The number of columns in the re-sized terminal.

           errstr
                 If the change_winsize() function returns a value other than
                 1, the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

     log_suspend
           int (*log_suspend)(int signo, const char **errstr);

           The log_suspend() function is called whenever a command is
           suspended or resumed.  Logging this information makes it possible
           to skip the period of time when the command was suspended during
           playback of a session.  Returns -1 if an error occurred, in which
           case no further calls to log_suspend() will be made,

           The function arguments are as follows:

           signo
                 The signal that caused the command to be suspended, or
                 SIGCONT if the command was resumed.

           errstr
                 If the log_suspend() function returns a value other than 1,
                 the plugin may store a message describing the failure or
                 error in errstr.  The sudo front-end will then pass this
                 value to any registered audit plugins.  The string stored in
                 errstr must remain valid until the plugin's close() function
                 is called.

                 The errstr parameter is only available starting with API
                 version 1.15.  A plugin must check the API version specified
                 by the sudo front-end before using errstr.  Failure to do so
                 may result in a crash.

           event_alloc
                 struct sudo_plugin_event * (*event_alloc)(void);

                 The event_alloc() function is used to allocate a struct
                 sudo_plugin_event which provides access to the main sudo
                 event loop.  Unlike the other fields, the event_alloc()
                 pointer is filled in by the sudo front-end, not by the
                 plugin.

                 See the Event API section below for more information about
                 events.

                 The event_alloc() function is only available starting with
                 API version 1.15.  If the sudo front-end doesn't support API
                 version 1.15 or higher, event_alloc() will not be set.

           I/O Plugin Version Macros

           Same as for the Policy plugin API.

   Audit plugin API
     /* Audit plugin close function status types. */
     #define SUDO_PLUGIN_NO_STATUS           0
     #define SUDO_PLUGIN_WAIT_STATUS         1
     #define SUDO_PLUGIN_EXEC_ERROR          2
     #define SUDO_PLUGIN_SUDO_ERROR          3

     #define SUDO_AUDIT_PLUGIN 3
     struct audit_plugin {
         unsigned int type; /* always SUDO_AUDIT_PLUGIN */
         unsigned int version; /* always SUDO_API_VERSION */
         int (*open)(unsigned int version, sudo_conv_t conversation,
             sudo_printf_t sudo_plugin_printf, char * const settings[],
             char * const user_info[], int submit_optind,
             char * const submit_argv[], char * const submit_envp[],
             char * const plugin_options[], const char **errstr);
         void (*close)(int status_type, int status);
         int (*accept)(const char *plugin_name,
             unsigned int plugin_type, char * const command_info[],
             char * const run_argv[], char * const run_envp[],
             const char **errstr);
         int (*reject)(const char *plugin_name, unsigned int plugin_type,
             const char *audit_msg, char * const command_info[],
             const char **errstr);
         int (*error)(const char *plugin_name, unsigned int plugin_type,
             const char *audit_msg, char * const command_info[],
             const char **errstr);
         int (*show_version)(int verbose);
         void (*register_hooks)(int version,
             int (*register_hook)(struct sudo_hook *hook));
         void (*deregister_hooks)(int version,
             int (*deregister_hook)(struct sudo_hook *hook));
         struct sudo_plugin_event * (*event_alloc)(void);
     }

     An audit plugin can be used to log successful and unsuccessful attempts
     to run sudo independent of the policy or any I/O plugins.  Multiple audit
     plugins may be specified in sudo.conf(5).

     A struct audit_plugin has the following fields:

     type  The type field should always be set to SUDO_AUDIT_PLUGIN.

     version
           The version field should be set to SUDO_API_VERSION.

           This allows sudo to determine the API version the plugin was built
           against.

     open
           int (*open)(unsigned int version, sudo_conv_t conversation,
               sudo_printf_t sudo_plugin_printf, char * const settings[],
               char * const user_info[], int submit_optind,
               char * const submit_argv[], char * const submit_envp[],
               char * const plugin_options[], const char **errstr);

           The audit open() function is run before any other sudo plugin API
           functions.  This makes it possible to audit failures in the other
           plugins.  It returns 1 on success, 0 on failure, -1 if a general
           error occurred, or -2 if there was a usage error.  In the latter
           case, sudo will print a usage message before it exits.  If an error
           occurs, the plugin may optionally call the conversation() or
           plugin_printf() function with SUDO_CONF_ERROR_MSG to present
           additional error information to the user.

           The function arguments are as follows:

           version
                 The version passed in by sudo allows the plugin to determine
                 the major and minor version number of the plugin API
                 supported by sudo.

           conversation
                 A pointer to the conversation() function that may be used by
                 the show_version() function to display version information
                 (see show_version() below).  The conversation() function may
                 also be used to display additional error message to the user.
                 The conversation() function returns 0 on success, and -1 on
                 failure.

           plugin_printf
                 A pointer to a printf()-style function that may be used by
                 the show_version() function to display version information
                 (see show_version below).  The plugin_printf() function may
                 also be used to display additional error message to the user.
                 The plugin_printf() function returns number of characters
                 printed on success and -1 on failure.

           settings
                 A vector of user-supplied sudo settings in the form of
                 "name=value" strings.  The vector is terminated by a NULL
                 pointer.  These settings correspond to options the user
                 specified when running sudo.  As such, they will only be
                 present when the corresponding option has been specified on
                 the command line.

                 When parsing settings, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 settings.

           user_info
                 A vector of information about the user running the command in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing user_info, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           submit_optind
                 The index into submit_argv that corresponds to the first
                 entry that is not a command line option.  If submit_argv only
                 consists of options, which may be the case with the -l or -v
                 options, submit_argv[submit_optind] will evaluate to the NULL
                 pointer.

           submit_argv
                 The argument vector sudo was invoked with, including all
                 command line options.  The submit_optind argument can be used
                 to determine the end of the command line options.

           submit_envp
                 The invoking user's environment in the form of a
                 NULL-terminated vector of "name=value" strings.

                 When parsing submit_envp, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

           plugin_options
                 Any (non-comment) strings immediately after the plugin path
                 are treated as arguments to the plugin.  These arguments are
                 split on a white space boundary and are passed to the plugin
                 in the form of a NULL-terminated array of strings.  If no
                 arguments were specified, plugin_options will be the NULL
                 pointer.

           errstr
                 If the open() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     close
           void (*close)(int status_type, int status);

           The close() function is called when sudo is finished, shortly
           before it exits.

           The function arguments are as follows:

           status_type
                 The type of status being passed.  One of
                 SUDO_PLUGIN_NO_STATUS, SUDO_PLUGIN_WAIT_STATUS,
                 SUDO_PLUGIN_EXEC_ERROR or SUDO_PLUGIN_SUDO_ERROR.

           status
                 Depending on the value of status_type, this value is either
                 ignored, the command's exit status as returned by the wait(2)
                 system call, the value of errno set by the execve(2) system
                 call, or the value of errno resulting from an error in the
                 sudo front-end.

     accept
           int (*accept)(const char *plugin_name, unsigned int plugin_type,
               char * const command_info[], char * const run_argv[],
               char * const run_envp[], const char **errstr);

           The accept() function is called when a command or action is
           accepted by a policy or approval plugin.  The function arguments
           are as follows:

           plugin_name
                 The name of the plugin that accepted the command or "sudo"
                 for the sudo front-end.

           plugin_type
                 The type of plugin that accepted the command, currently
                 either SUDO_POLICY_PLUGIN, SUDO_POLICY_APPROVAL, or
                 SUDO_FRONT_END.  The accept() 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, command_info may include information from
                 an I/O logging plugin as well.

                 Typically, an audit plugin is interested in either the accept
                 status from the sudo 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 accept()
                 and reject() functions will both be called.

           command_info
                 An optional vector of information describing the command
                 being run in the form of "name=value" strings.  The vector is
                 terminated by a NULL pointer.

                 When parsing command_info, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           run_argv
                 A NULL-terminated argument vector describing a command that
                 will be run in the same form as what would be passed to the
                 execve(2) system call.

           run_envp
                 The environment the command will be run with in the form of a
                 NULL-terminated vector of "name=value" strings.

                 When parsing run_envp, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

           errstr
                 If the accept() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     reject
           int (*reject)(const char *plugin_name, unsigned int plugin_type,
               const char *audit_msg, char * const command_info[],
               const char **errstr);

           The reject() function is called when a command or action is
           rejected by a plugin.  The function arguments are as follows:

           plugin_name
                 The name of the plugin that rejected the command.

           plugin_type
                 The type of plugin that rejected the command, currently
                 either SUDO_POLICY_PLUGIN, SUDO_APPROVAL_PLUGIN, or
                 SUDO_IO_PLUGIN.

                 Unlike the accept() function, the reject() function is not
                 called on behalf of the sudo front-end.

           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 the NULL pointer.

           command_info
                 An optional vector of information describing the command
                 being run in the form of "name=value" strings.  The vector is
                 terminated by a NULL pointer.

                 When parsing command_info, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           errstr
                 If the reject() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     error
           int (*error)(const char *plugin_name, unsigned int plugin_type,
               const char *audit_msg, char * const command_info[],
               const char **errstr);

           The error() function is called when a plugin or the sudo front-end
           returns an error.  The function arguments are as follows:

           plugin_name
                 The name of the plugin that generated the error or "sudo" for
                 the sudo front-end.

           plugin_type
                 The type of plugin that generated the error, or
                 SUDO_FRONT_END for the sudo front-end.

           audit_msg
                 An optional string describing the plugin error.  If the
                 plugin did not provide a description, audit_msg will be the
                 NULL pointer.

           command_info
                 An optional vector of information describing the command
                 being run in the form of "name=value" strings.  The vector is
                 terminated by a NULL pointer.

                 When parsing command_info, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           errstr
                 If the error() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     show_version
           int (*show_version)(int verbose);

           The show_version() function is called by sudo when the user
           specifies the -V option.  The plugin may display its version
           information to the user via the conversation() or plugin_printf()
           function using SUDO_CONV_INFO_MSG.  If the user requests detailed
           version information, the verbose flag will be set.

           Returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error, although the return value is
           currently ignored.

     register_hooks
           See the Policy plugin API section for a description of
           register_hooks().

     deregister_hooks
           See the Policy plugin API section for a description of
           deregister_hooks().

     event_alloc
           struct sudo_plugin_event * (*event_alloc)(void);

           The event_alloc() function is used to allocate a struct
           sudo_plugin_event which provides access to the main sudo event
           loop.  Unlike the other fields, the event_alloc pointer is filled
           in by the sudo front-end, not by the plugin.

           See the Event API section below for more information about events.

           The event_alloc() function is only available starting with API
           version 1.17.  If the sudo front-end doesn't support API version
           1.17 or higher, event_alloc() will not be set.

   Approval plugin API
     struct approval_plugin {
     #define SUDO_APPROVAL_PLUGIN 4
         unsigned int type; /* always SUDO_APPROVAL_PLUGIN */
         unsigned int version; /* always SUDO_API_VERSION */
         int (*open)(unsigned int version, sudo_conv_t conversation,
             sudo_printf_t sudo_plugin_printf, char * const settings[],
             char * const user_info[], int submit_optind,
             char * const submit_argv[], char * const submit_envp[],
             char * const plugin_options[], const char **errstr);
         void (*close)(void);
         int (*check)(char * const command_info[], char * const run_argv[],
             char * const run_envp[], const char **errstr);
         int (*show_version)(int verbose);
     };

     An approval plugin can be used to apply extra constraints after a command
     has been accepted by the policy plugin.  Unlike the other plugin types,
     it does not remain open until the command completes.  The plugin is
     opened before a call to check() or show_version() and closed shortly
     thereafter (audit plugin functions must be called before the plugin is
     closed).  Multiple approval plugins may be specified in sudo.conf(5).

     A struct approval_plugin has the following fields:

     type  The type field should always be set to SUDO_APPROVAL_PLUGIN.

     version
           The version field should be set to SUDO_API_VERSION.

           This allows sudo to determine the API version the plugin was built
           against.

     open
           int (*open)(unsigned int version, sudo_conv_t conversation,
               sudo_printf_t sudo_plugin_printf, char * const settings[],
               char * const user_info[], int submit_optind,
               char * const submit_argv[], char * const submit_envp[],
               char * const plugin_options[], const char **errstr);

           The approval open() function is run immediately before a call to
           the plugin's check() or show_version() functions.  It is only
           called if the version is being requested or if the policy plugin's
           check_policy() function has returned successfully.  It returns 1 on
           success, 0 on failure, -1 if a general error occurred, or -2 if
           there was a usage error.  In the latter case, sudo will print a
           usage message before it exits.  If an error occurs, the plugin may
           optionally call the conversation() or plugin_printf() function with
           SUDO_CONF_ERROR_MSG to present additional error information to the
           user.

           The function arguments are as follows:

           version
                 The version passed in by sudo allows the plugin to determine
                 the major and minor version number of the plugin API
                 supported by sudo.

           conversation
                 A pointer to the conversation() function that can be used by
                 the plugin to interact with the user (see Conversation API
                 for details).  Returns 0 on success and -1 on failure.

           plugin_printf
                 A pointer to a printf()-style function that may be used to
                 display informational or error messages (see Conversation API
                 for details).  Returns the number of characters printed on
                 success and -1 on failure.

           settings
                 A vector of user-supplied sudo settings in the form of
                 "name=value" strings.  The vector is terminated by a NULL
                 pointer.  These settings correspond to options the user
                 specified when running sudo.  As such, they will only be
                 present when the corresponding option has been specified on
                 the command line.

                 When parsing settings, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 settings.

           user_info
                 A vector of information about the user running the command in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing user_info, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           submit_optind
                 The index into submit_argv that corresponds to the first
                 entry that is not a command line option.  If submit_argv only
                 consists of options, which may be the case with the -l or -v
                 options, submit_argv[submit_optind] will evaluate to the NULL
                 pointer.

           submit_argv
                 The argument vector sudo was invoked with, including all
                 command line options.  The submit_optind argument can be used
                 to determine the end of the command line options.

           submit_envp
                 The invoking user's environment in the form of a
                 NULL-terminated vector of "name=value" strings.

                 When parsing submit_envp, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

           plugin_options
                 Any (non-comment) strings immediately after the plugin path
                 are treated as arguments to the plugin.  These arguments are
                 split on a white space boundary and are passed to the plugin
                 in the form of a NULL-terminated array of strings.  If no
                 arguments were specified, plugin_options will be the NULL
                 pointer.

           errstr
                 If the open() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     close
           void (*close)(void);

           The close() function is called after the approval plugin's check()
           or show_version() functions have been called.  It takes no
           arguments.  The close() function is typically used to perform
           plugin-specific cleanup, such as the freeing of memory objects
           allocated by the plugin.  If the plugin does not need to perform
           any cleanup, close() may be set to the NULL pointer.

     check
           int (*check)(char * const command_info[], char * const run_argv[],
               char * const run_envp[], const char **errstr);

           The approval check() function is run after the policy plugin
           check_policy() function and before any I/O logging plugins.  If
           multiple approval plugins are loaded, they must all succeed for the
           command to be allowed.  It returns 1 on success, 0 on failure, -1
           if a general error occurred, or -2 if there was a usage error.  In
           the latter case, sudo will print a usage message before it exits.
           If an error occurs, the plugin may optionally call the
           conversation() or plugin_printf() function with SUDO_CONF_ERROR_MSG
           to present additional error information to the user.

           The function arguments are as follows:

           command_info
                 A vector of information describing the command being run in
                 the form of "name=value" strings.  The vector is terminated
                 by a NULL pointer.

                 When parsing command_info, the plugin should split on the
                 first equal sign (`=') since the name field will never
                 include one itself but the value might.

                 See the Policy plugin API section for a list of all possible
                 strings.

           run_argv
                 A NULL-terminated argument vector describing a command that
                 will be run in the same form as what would be passed to the
                 execve(2) system call.

           run_envp
                 The environment the command will be run with in the form of a
                 NULL-terminated vector of "name=value" strings.

                 When parsing run_envp, the plugin should split on the first
                 equal sign (`=') since the name field will never include one
                 itself but the value might.

           errstr
                 If the open() function returns a value other than 1, the
                 plugin may store a message describing the failure or error in
                 errstr.  The sudo front-end will then pass this value to any
                 registered audit plugins.  The string stored in errstr must
                 remain valid until the plugin's close() function is called.

     show_version
           int (*show_version)(int verbose);

           The show_version() function is called by sudo when the user
           specifies the -V option.  The plugin may display its version
           information to the user via the conversation() or plugin_printf()
           function using SUDO_CONV_INFO_MSG.  If the user requests detailed
           version information, the verbose flag will be set.

           Returns 1 on success, 0 on failure, -1 if a general error occurred,
           or -2 if there was a usage error, although the return value is
           currently ignored.

   Signal handlers
     The sudo front-end installs default signal handlers to trap common
     signals while the plugin functions are run.  The following signals are
     trapped by default before the command is executed:

     o  SIGALRM
     o  SIGHUP
     o  SIGINT
     o  SIGPIPE
     o  SIGQUIT
     o  SIGTERM
     o  SIGTSTP
     o  SIGUSR1
     o  SIGUSR2

     If a fatal signal is received before the command is executed, sudo will
     call the plugin's close() function with an exit status of 128 plus the
     value of the signal that was received.  This allows for consistent
     logging of commands killed by a signal for plugins that log such
     information in their close() function.  An exception to this is SIGPIPE,
     which is ignored until the command is executed.

     A plugin may temporarily install its own signal handlers but must restore
     the original handler before the plugin function returns.

   Hook function API
     Beginning with plugin API version 1.2, it is possible to install hooks
     for certain functions called by the sudo front-end.

     Currently, the only supported hooks relate to the handling of environment
     variables.  Hooks can be used to intercept attempts to get, set, or
     remove environment variables so that these changes can be reflected in
     the version of the environment that is used to execute a command.  A
     future version of the API will support hooking internal sudo front-end
     functions as well.

     Hook structure

     Hooks in sudo are described by the following structure:

     typedef int (*sudo_hook_fn_t)();

     struct sudo_hook {
         unsigned int hook_version;
         unsigned int hook_type;
         sudo_hook_fn_t hook_fn;
         void *closure;
     };

     A struct sudo_hook has the following fields:

     hook_version
           The hook_version field should be set to SUDO_HOOK_VERSION.

     hook_type
           The hook_type field may be one of the following supported hook
           types:

           SUDO_HOOK_SETENV
                 The C library setenv(3) function.  Any registered hooks will
                 run before the C library implementation.  The hook_fn field
                 should be a function that matches the following typedef:

                 typedef int (*sudo_hook_fn_setenv_t)(const char *name,
                    const char *value, int overwrite, void *closure);

                 If the registered hook does not match the typedef the results
                 are unspecified.

           SUDO_HOOK_UNSETENV
                 The C library unsetenv(3) function.  Any registered hooks
                 will run before the C library implementation.  The hook_fn
                 field should be a function that matches the following
                 typedef:

                 typedef int (*sudo_hook_fn_unsetenv_t)(const char *name,
                    void *closure);

           SUDO_HOOK_GETENV
                 The C library getenv(3) function.  Any registered hooks will
                 run before the C library implementation.  The hook_fn field
                 should be a function that matches the following typedef:

                 typedef int (*sudo_hook_fn_getenv_t)(const char *name,
                    char **value, void *closure);

                 If the registered hook does not match the typedef the results
                 are unspecified.

           SUDO_HOOK_PUTENV
                 The C library putenv(3) function.  Any registered hooks will
                 run before the C library implementation.  The hook_fn field
                 should be a function that matches the following typedef:

                 typedef int (*sudo_hook_fn_putenv_t)(char *string,
                    void *closure);

                 If the registered hook does not match the typedef the results
                 are unspecified.

     hook_fn
           sudo_hook_fn_t hook_fn;

           The hook_fn field should be set to the plugin's hook
           implementation.  The actual function arguments will vary depending
           on the hook_type (see hook_type above).  In all cases, the closure
           field of struct sudo_hook is passed as the last function parameter.
           This can be used to pass arbitrary data to the plugin's hook
           implementation.

           The function return value may be one of the following:

           SUDO_HOOK_RET_ERROR
                 The hook function encountered an error.

           SUDO_HOOK_RET_NEXT
                 The hook completed without error, go on to the next hook
                 (including the system implementation if applicable).  For
                 example, a getenv(3) hook might return SUDO_HOOK_RET_NEXT if
                 the specified variable was not found in the private copy of
                 the environment.

           SUDO_HOOK_RET_STOP
                 The hook completed without error, stop processing hooks for
                 this invocation.  This can be used to replace the system
                 implementation.  For example, a setenv hook that operates on
                 a private copy of the environment but leaves environ
                 unchanged.

     Care must be taken when hooking C library functions, it is very easy to
     create an infinite loop.  For example, a getenv(3) hook that calls the
     snprintf(3) function may create a loop if the snprintf(3) implementation
     calls getenv(3) to check the locale.  To prevent this, you may wish to
     use a static variable in the hook function to guard against nested calls.
     For example:

           static int in_progress = 0; /* avoid recursion */
           if (in_progress)
               return SUDO_HOOK_RET_NEXT;
           in_progress = 1;
           ...
           in_progress = 0;
           return SUDO_HOOK_RET_STOP;

     Hook API Version Macros

     /* Hook API version major/minor */
     #define SUDO_HOOK_VERSION_MAJOR 1
     #define SUDO_HOOK_VERSION_MINOR 0
     #define SUDO_HOOK_VERSION SUDO_API_MKVERSION(SUDO_HOOK_VERSION_MAJOR,\
                                                   SUDO_HOOK_VERSION_MINOR)

     For getters and setters see the Policy plugin API.

   Event API
     When sudo runs a command, it uses an event loop to service signals and
     I/O.  Events may be triggered based on time, a file or socket descriptor
     becoming ready, or due to receipt of a signal.  Starting with API version
     1.15, it is possible for a plugin to participate in this event loop by
     calling the event_alloc() function.

     Event structure

     Events are described by the following structure:

     typedef void (*sudo_plugin_ev_callback_t)(int fd, int what, void *closure);

     struct sudo_plugin_event {
         int (*set)(struct sudo_plugin_event *pev, int fd, int events,
             sudo_plugin_ev_callback_t callback, void *closure);
         int (*add)(struct sudo_plugin_event *pev, struct timespec *timeout);
         int (*del)(struct sudo_plugin_event *pev);
         int (*pending)(struct sudo_plugin_event *pev, int events,
             struct timespec *ts);
         int (*fd)(struct sudo_plugin_event *pev);
         void (*setbase)(struct sudo_plugin_event *pev, void *base);
         void (*loopbreak)(struct sudo_plugin_event *pev);
         void (*free)(struct sudo_plugin_event *pev);
     };

     A struct sudo_plugin_event contains the following function pointers:

     set
           int (*set)(struct sudo_plugin_event *pev, int fd, int events,
               sudo_plugin_ev_callback_t callback, void *closure);

           The set() function takes the following arguments:

           struct sudo_plugin_event *pev
                 A pointer to the struct sudo_plugin_event itself.

           fd    The file or socket descriptor for I/O-based events or the
                 signal number for signal events.  For time-based events, fd
                 must be -1.

           events
                 The following values determine what will trigger the event
                 callback:

                 SUDO_PLUGIN_EV_TIMEOUT
                       callback is run after the specified timeout expires

                 SUDO_PLUGIN_EV_READ
                       callback is run when the file descriptor is readable

                 SUDO_PLUGIN_EV_WRITE
                       callback is run when the file descriptor is writable

                 SUDO_PLUGIN_EV_PERSIST
                       event is persistent and remains enabled until
                       explicitly deleted

                 SUDO_PLUGIN_EV_SIGNAL
                       callback is run when the specified signal is received

                 The SUDO_PLUGIN_EV_PERSIST flag may be ORed with any of the
                 event types.  It is also possible to OR SUDO_PLUGIN_EV_READ
                 and SUDO_PLUGIN_EV_WRITE together to run the callback when a
                 descriptor is ready to be either read from or written to.
                 All other event values are mutually exclusive.

           sudo_plugin_ev_callback_t callback
                 typedef void (*sudo_plugin_ev_callback_t)(int fd, int what,
                     void *closure);

                 The function to call when an event is triggered.  The
                 callback() function is run with the following arguments:

                 fd    The file or socket descriptor for I/O-based events or
                       the signal number for signal events.

                 what  The event type that triggered that callback.  For
                       events that have multiple event types (for example
                       SUDO_PLUGIN_EV_READ and SUDO_PLUGIN_EV_WRITE) or have
                       an associated timeout, what can be used to determine
                       why the callback was run.

                 closure
                       The generic pointer that was specified in the set()
                       function.

           closure
                 A generic pointer that will be passed to the callback
                 function.

           The set() function returns 1 on success, and -1 if a error
           occurred.

     add
           int (*add)(struct sudo_plugin_event *pev, struct timespec *timeout);

           The add() function adds the event pev to sudo's event loop.  The
           event must have previously been initialized via the set() function.
           If the timeout argument is not NULL, it should specify a (relative)
           timeout after which the event will be triggered if the main event
           criteria has not been met.  This is often used to implement an I/O
           timeout where the event will fire if a descriptor is not ready
           within a certain time period.  If the event is already present in
           the event loop, its timeout will be adjusted to match the new
           value, if any.

           The add() function returns 1 on success, and -1 if a error
           occurred.

     del
           int (*del)(struct sudo_plugin_event *pev);

           The del() function deletes the event pev from sudo's event loop.
           Deleted events can be added back via the add() function.

           The del() function returns 1 on success, and -1 if a error
           occurred.

     pending
           int (*pending)(struct sudo_plugin_event *pev, int events,
               struct timespec *ts);

           The pending() function can be used to determine whether one or more
           events is pending.  The events argument specifies which events to
           check for.  See the set() function for a list of valid event types.
           If SUDO_PLUGIN_EV_TIMEOUT is specified in events, the event has an
           associated timeout and the ts pointer is non-NULL, it will be
           filled in with the remaining time.

     fd
           int (*fd)(struct sudo_plugin_event *pev);

           The fd() function returns the descriptor or signal number
           associated with the event pev.

     setbase
           void (*setbase)(struct sudo_plugin_event *pev, void *base);

           The setbase() function sets the underlying event base for pev to
           the specified value.  This can be used to move an event created via
           event_alloc() to a new event loop allocated by sudo's event
           subsystem.  If base is NULL, pev's event base is reset to the
           default value, which corresponds to sudo's main event loop.  Using
           this function requires linking the plugin with the sudo_util
           library.  It is unlikely to be used outside of the sudoers plugin.

     loopbreak
           void (*loopbreak)(struct sudo_plugin_event *pev);

           The loopbreak() function causes sudo's event loop to exit
           immediately and the running command to be terminated.

     free
           void (*free)(struct sudo_plugin_event *pev);

           The free() function deletes the event pev from the event loop and
           frees the memory associated with it.

   Remote command execution
     The sudo front-end does not support running remote commands.  However,
     starting with sudo 1.8.8, the -h option may be used to specify a remote
     host that is passed to the policy plugin.  A plugin may also accept a
     runas_user in the form of "user@hostname" which will work with older
     versions of sudo.  It is anticipated that remote commands will be
     supported by executing a "helper" program.  The policy plugin should
     setup the execution environment such that the sudo front-end will run the
     helper which, in turn, will connect to the remote host and run the
     command.

     For example, the policy plugin could utilize ssh to perform remote
     command execution.  The helper program would be responsible for running
     ssh with the proper options to use a private key or certificate that the
     remote host will accept and run a program on the remote host that would
     setup the execution environment accordingly.

     Remote sudoedit functionality must be handled by the policy plugin, not
     sudo itself as the front-end has no knowledge that a remote command is
     being executed.  This may be addressed in a future revision of the plugin
     API.

   Conversation API
     If the plugin needs to interact with the user, it may do so via the
     conversation() function.  A plugin should not attempt to read directly
     from the standard input or the user's terminal (neither of which are
     guaranteed to exist).  The caller must include a trailing newline in msg
     if one is to be printed.

     A printf()-style function is also available that can be used to display
     informational or error messages to the user, which is usually more
     convenient for simple messages where no use input is required.

     Conversation function structures

     The conversation function takes as arguments pointers to the following
     structures:

     struct sudo_conv_message {
     #define SUDO_CONV_PROMPT_ECHO_OFF  0x0001 /* do not echo user input */
     #define SUDO_CONV_PROMPT_ECHO_ON   0x0002 /* echo user input */
     #define SUDO_CONV_ERROR_MSG        0x0003 /* error message */
     #define SUDO_CONV_INFO_MSG         0x0004 /* informational message */
     #define SUDO_CONV_PROMPT_MASK      0x0005 /* mask user input */
     #define SUDO_CONV_PROMPT_ECHO_OK   0x1000 /* flag: allow echo if no tty */
     #define SUDO_CONV_PREFER_TTY       0x2000 /* flag: use tty if possible */
         int msg_type;
         int timeout;
         const char *msg;
     };

     #define SUDO_CONV_REPL_MAX      1023

     struct sudo_conv_reply {
         char *reply;
     };

     typedef int (*sudo_conv_callback_fn_t)(int signo, void *closure);
     struct sudo_conv_callback {
         unsigned int version;
         void *closure;
         sudo_conv_callback_fn_t on_suspend;
         sudo_conv_callback_fn_t on_resume;
     };

     Pointers to the conversation() and printf()-style functions are passed in
     to the plugin's open() function when the plugin is initialized.  The
     following type definitions can be used in the declaration of the open()
     function:

     typedef int (*sudo_conv_t)(int num_msgs,
         const struct sudo_conv_message msgs[],
         struct sudo_conv_reply replies[], struct sudo_conv_callback *callback);

     typedef int (*sudo_printf_t)(int msg_type, const char * restrict fmt, ...);

     To use the conversation() function, the plugin must pass an array of
     struct sudo_conv_message and struct sudo_conv_reply.  There must be a
     struct sudo_conv_message and struct sudo_conv_reply for each message in
     the conversation, that is, both arrays must have the same number of
     elements.  Each struct sudo_conv_reply must have its reply member
     initialized to NULL.  The struct sudo_conv_callback pointer, if not NULL,
     should contain function pointers to be called when the sudo process is
     suspended and/or resumed during conversation input.  The on_suspend and
     on_resume functions are called with the signal that caused sudo to be
     suspended and the closure pointer from the struct sudo_conv_callback.
     These functions should return 0 on success and -1 on error.  On error,
     the conversation will end and the conversation function will return a
     value of -1.  The intended use is to allow the plugin to release
     resources, such as locks, that should not be held indefinitely while
     suspended and then reacquire them when the process is resumed.  The
     functions are not actually invoked from within a signal handler.

     The msg_type must be set to one of the following values:

     SUDO_CONV_PROMPT_ECHO_OFF
           Prompt the user for input with echo disabled; this is generally
           used for passwords.  The reply will be stored in the replies array,
           and it will never be NULL.

     SUDO_CONV_PROMPT_ECHO_ON
           Prompt the user for input with echo enabled.  The reply will be
           stored in the replies array, and it will never be NULL.

     SUDO_CONV_ERROR_MSG
           Display an error message.  The message is written to the standard
           error unless the SUDO_CONV_PREFER_TTY flag is set, in which case it
           is written to the user's terminal if possible.

     SUDO_CONV_INFO_MSG
           Display a message.  The message is written to the standard output
           unless the SUDO_CONV_PREFER_TTY flag is set, in which case it is
           written to the user's terminal if possible.

     SUDO_CONV_PROMPT_MASK
           Prompt the user for input but echo an asterisk character for each
           character read.  The reply will be stored in the replies array, and
           it will never be NULL.  This can be used to provide visual feedback
           to the user while reading sensitive information that should not be
           displayed.

     In addition to the above values, the following flag bits may also be set:

     SUDO_CONV_PROMPT_ECHO_OK
           Allow input to be read when echo cannot be disabled when the
           message type is SUDO_CONV_PROMPT_ECHO_OFF or SUDO_CONV_PROMPT_MASK.
           By default, sudo will refuse to read input if the echo cannot be
           disabled for those message types.

     SUDO_CONV_PREFER_TTY
           When displaying a message via SUDO_CONV_ERROR_MSG or
           SUDO_CONV_INFO_MSG, try to write the message to the user's
           terminal.  If the terminal is unavailable, the standard error or
           standard output will be used, depending upon whether
           SUDO_CONV_ERROR_MSG or SUDO_CONV_INFO_MSG was used.  The user's
           terminal is always used when possible for input, this flag is only
           used for output.

     The timeout in seconds until the prompt will wait for no more input.  A
     zero value implies an infinite timeout.

     The plugin is responsible for freeing the reply buffer located in each
     struct sudo_conv_reply, if it is not NULL.  SUDO_CONV_REPL_MAX represents
     the maximum length of the reply buffer (not including the trailing NUL
     character).  In practical terms, this is the longest password sudo will
     support.

     The printf()-style function uses the same underlying mechanism as the
     conversation() function but only supports SUDO_CONV_INFO_MSG and
     SUDO_CONV_ERROR_MSG for the msg_type parameter.  It can be more
     convenient than using the conversation() function if no user reply is
     needed and supports standard printf() escape sequences.

     See the sample plugin for an example of the conversation() function
     usage.

   Plugin invocation order
     As of sudo 1.9.0, the plugin open() and close() functions are called in
     the following order:

     1.   audit open

     2.   policy open

     3.   approval open

     4.   approval close

     5.   I/O log open

     6.   command runs

     7.   command exits

     8.   I/O log close

     9.   policy close

     10.  audit close

     11.  sudo exits

     Prior to sudo 1.9.0, the I/O log close() function was called after the
     policy close() function.

   Sudoers group plugin API
     The sudoers plugin supports its own plugin interface to allow non-Unix
     group lookups.  This can be used to query a group source other than the
     standard Unix group database.  Two sample group plugins are bundled with
     sudo, group_file, and system_group, are detailed in sudoers(5).  Third
     party group plugins include a QAS AD plugin available from Quest
     Software.

     A group plugin must declare and populate a struct sudoers_group_plugin in
     the global scope.  This structure contains pointers to the functions that
     implement plugin initialization, cleanup, and group lookup.

     struct sudoers_group_plugin {
         unsigned int version;
         int (*init)(int version, sudo_printf_t sudo_plugin_printf,
             char *const argv[]);
         void (*cleanup)(void);
         int (*query)(const char *user, const char *group,
             const struct passwd *pwd);
     };

     A struct sudoers_group_plugin has the following fields:

     version
           The version field should be set to GROUP_API_VERSION.

           This allows sudoers to determine the API version the group plugin
           was built against.

     init
           int (*init)(int version, sudo_printf_t sudo_plugin_printf,
               char *const argv[]);

           The init() function is called after sudoers has been parsed but
           before any policy checks.  It returns 1 on success, 0 on failure
           (or if the plugin is not configured), and -1 if a error occurred.
           If an error occurs, the plugin may call the plugin_printf()
           function with SUDO_CONF_ERROR_MSG to present additional error
           information to the user.

           The function arguments are as follows:

           version
                 The version passed in by sudoers allows the plugin to
                 determine the major and minor version number of the group
                 plugin API supported by sudoers.

           plugin_printf
                 A pointer to a printf()-style function that may be used to
                 display informational or error message to the user.  Returns
                 the number of characters printed on success and -1 on
                 failure.

           argv  A NULL-terminated array of arguments generated from the
                 group_plugin option in sudoers.  If no arguments were given,
                 argv will be NULL.

     cleanup
           void (*cleanup)();

           The cleanup() function is called when sudoers has finished its
           group checks.  The plugin should free any memory it has allocated
           and close open file handles.

     query
           int (*query)(const char *user, const char *group,
               const struct passwd *pwd);

           The query() function is used to ask the group plugin whether user
           is a member of group.

           The function arguments are as follows:

           user  The name of the user being looked up in the external group
                 database.

           group
                 The name of the group being queried.

           pwd   The password database entry for user, if any.  If user is not
                 present in the password database, pwd will be NULL.

     Group API Version Macros

     /* Sudoers group plugin version major/minor */
     #define GROUP_API_VERSION_MAJOR 1
     #define GROUP_API_VERSION_MINOR 0
     #define GROUP_API_VERSION ((GROUP_API_VERSION_MAJOR << 16) | \
                                GROUP_API_VERSION_MINOR)
     For getters and setters see the Policy plugin API.


PLUGIN API CHANGELOG

     The following revisions have been made to the Sudo Plugin API.

     Version 1.0
           Initial API version.

     Version 1.1 (sudo 1.8.0)
           The I/O logging plugin's open() function was modified to take the
           command_info list as an argument.

     Version 1.2 (sudo 1.8.5)
           The Policy and I/O logging plugins' open() functions are now passed
           a list of plugin parameters if any are specified in sudo.conf(5).

           A simple hooks API has been introduced to allow plugins to hook in
           to the system's environment handling functions.

           The init_session() Policy plugin function is now passed a pointer
           to the user environment which can be updated as needed.  This can
           be used to merge in environment variables stored in the PAM handle
           before a command is run.

     Version 1.3 (sudo 1.8.7)
           Support for the exec_background entry has been added to the
           command_info list.

           The max_groups and plugin_dir entries were added to the settings
           list.

           The version() and close() functions are now optional.  Previously,
           a missing version() or close() function would result in a crash.
           If no policy plugin close() function is defined, a default close()
           function will be provided by the sudo front-end that displays a
           warning if the command could not be executed.

           The sudo front-end now installs default signal handlers to trap
           common signals while the plugin functions are run.

     Version 1.4 (sudo 1.8.8)
           The remote_host entry was added to the settings list.

     Version 1.5 (sudo 1.8.9)
           The preserve_fds entry was added to the command_info list.

     Version 1.6 (sudo 1.8.11)
           The behavior when an I/O logging plugin returns an error (-1) has
           changed.  Previously, the sudo front-end took no action when the
           log_ttyin(), log_ttyout(), log_stdin(), log_stdout(), or
           log_stderr() function returned an error.

           The behavior when an I/O logging plugin returns 0 has changed.
           Previously, output from the command would be displayed to the
           terminal even if an output logging function returned 0.

     Version 1.7 (sudo 1.8.12)
           The plugin_path entry was added to the settings list.

           The debug_flags entry now starts with a debug file path name and
           may occur multiple times if there are multiple plugin-specific
           Debug lines in the sudo.conf(5) file.

     Version 1.8 (sudo 1.8.15)
           The sudoedit_checkdir and sudoedit_follow entries were added to the
           command_info list.  The default value of sudoedit_checkdir was
           changed to true in sudo 1.8.16.

           The sudo conversation() function now takes a pointer to a struct
           sudo_conv_callback as its fourth argument.  The sudo_conv_t
           definition has been updated to match.  The plugin must specify that
           it supports plugin API version 1.8 or higher to receive a
           conversation function pointer that supports this argument.

     Version 1.9 (sudo 1.8.16)
           The execfd entry was added to the command_info list.

     Version 1.10 (sudo 1.8.19)
           The umask entry was added to the user_info list.  The iolog_group,
           iolog_mode, and iolog_user entries were added to the command_info
           list.

     Version 1.11 (sudo 1.8.20)
           The timeout entry was added to the settings list.

     Version 1.12 (sudo 1.8.21)
           The change_winsize() function was added to struct io_plugin.

     Version 1.13 (sudo 1.8.26)
           The log_suspend() function was added to struct io_plugin.

     Version 1.14 (sudo 1.8.29)
           The umask_override entry was added to the command_info list.

     Version 1.15 (sudo 1.9.0)
           The cwd_optional entry was added to the command_info list.

           The event_alloc() function was added to struct policy_plugin and
           struct io_plugin.

           The errstr argument was added to the policy and I/O plugin
           functions which the plugin function can use to return an error
           string.  This string may be used by the audit plugin to report
           failure or error conditions set by the other plugins.

           The close() function is now is called regardless of whether or not
           a command was actually executed.  This makes it possible for
           plugins to perform cleanup even when a command was not run.

           SUDO_CONV_REPL_MAX has increased from 255 to 1023 bytes.

           Support for audit and approval plugins was added.

     Version 1.16 (sudo 1.9.3)
           Initial resource limit values were added to the user_info list.

           The cmnd_chroot and cmnd_cwd entries were added to the settings
           list.

     Version 1.17 (sudo 1.9.4)
           The event_alloc() function was added to struct audit_plugin and
           struct approval_plugin.

     Version 1.18 (sudo 1.9.9)
           The policy may now set resource limit values in the command_info
           list.  The intercept and log_subcmds entries were added to the
           command_info list.

     Version 1.19 (sudo 1.9.11)
           The intercept_ptrace and intercept_setid entries were added to the
           settings list.  The apparmor_profile and use_ptrace entries were
           added to the command_info list.

     Version 1.20 (sudo 1.9.12)
           The update_ticket entry was added to the settings list.  The
           intercept_verify entry was added to the command_info list.

     Version 1.21 (sudo 1.9.13)
           The sudoedit_nfiles entry was added to the command_info list.


SEE ALSO

     sudo.conf(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 1.9.15                      July 10, 2023                     Sudo 1.9.15

sudo 1.9.15 - Generated Mon Nov 6 18:43:53 CST 2023
© manpagez.com 2000-2024
Individual documents may contain additional copyright information.