SUDOERS(4)                    File Formats Manual                   SUDOERS(4)

NNAAMMEE
     ssuuddooeerrss - default sudo security policy plugin

DDEESSCCRRIIPPTTIIOONN
     The ssuuddooeerrss policy plugin determines a user's ssuuddoo privileges.  It is the
     default ssuuddoo policy plugin.  The policy is driven by the _/_e_t_c_/_s_u_d_o_e_r_s
     file or, optionally in LDAP.  The policy format is described in detail in
     the _S_U_D_O_E_R_S _F_I_L_E _F_O_R_M_A_T section.  For information on storing ssuuddooeerrss
     policy information in LDAP, please see sudoers.ldap(4).

   CCoonnffiigguurriinngg ssuuddoo..ccoonnff ffoorr ssuuddooeerrss
     ssuuddoo consults the sudo.conf(4) file to determine which policy and I/O
     logging plugins to load.  If no sudo.conf(4) file is present, or if it
     contains no Plugin lines, ssuuddooeerrss will be used for policy decisions and
     I/O logging.  To explicitly configure sudo.conf(4) to use the ssuuddooeerrss
     plugin, the following configuration can be used.

           Plugin sudoers_policy sudoers.so
           Plugin sudoers_io sudoers.so

     Starting with ssuuddoo 1.8.5, it is possible to specify optional arguments to
     the ssuuddooeerrss plugin in the sudo.conf(4) file.  These arguments, if
     present, should be listed after the path to the plugin (i.e., after
     _s_u_d_o_e_r_s_._s_o).  Multiple arguments may be specified, separated by white
     space.  For example:

           Plugin sudoers_policy sudoers.so sudoers_mode=0400

     The following plugin arguments are supported:

     ldap_conf=pathname
               The _l_d_a_p___c_o_n_f argument can be used to override the default path
               to the _l_d_a_p_._c_o_n_f file.

     ldap_secret=pathname
               The _l_d_a_p___s_e_c_r_e_t argument can be used to override the default
               path to the _l_d_a_p_._s_e_c_r_e_t file.

     sudoers_file=pathname
               The _s_u_d_o_e_r_s___f_i_l_e argument can be used to override the default
               path to the _s_u_d_o_e_r_s file.

     sudoers_uid=uid
               The _s_u_d_o_e_r_s___u_i_d argument can be used to override the default
               owner of the sudoers file.  It should be specified as a numeric
               user ID.

     sudoers_gid=gid
               The _s_u_d_o_e_r_s___g_i_d argument can be used to override the default
               group of the sudoers file.  It must be specified as a numeric
               group ID (not a group name).

     sudoers_mode=mode
               The _s_u_d_o_e_r_s___m_o_d_e argument can be used to override the default
               file mode for the sudoers file.  It should be specified as an
               octal value.

     For more information on configuring sudo.conf(4), please refer to its
     manual.

   UUsseerr AAuutthheennttiiccaattiioonn
     The ssuuddooeerrss security policy requires that most users authenticate
     themselves before they can use ssuuddoo.  A password is not required if the
     invoking user is root, if the target user is the same as the invoking
     user, or if the policy has disabled authentication for the user or
     command.  Unlike su(1), when ssuuddooeerrss requires authentication, it
     validates the invoking user's credentials, not the target user's (or
     root's) credentials.  This can be changed via the _r_o_o_t_p_w, _t_a_r_g_e_t_p_w and
     _r_u_n_a_s_p_w flags, described later.

     If a user who is not listed in the policy tries to run a command via
     ssuuddoo, mail is sent to the proper authorities.  The address used for such
     mail is configurable via the _m_a_i_l_t_o Defaults entry (described later) and
     defaults to root.

     Note that no mail will be sent if an unauthorized user tries to run ssuuddoo
     with the --ll or --vv option unless there is an authentication error and
     either the _m_a_i_l___a_l_w_a_y_s or _m_a_i_l___b_a_d_p_a_s_s flags are enabled.  This allows
     users to determine for themselves whether or not they are allowed to use
     ssuuddoo.  All attempts to run ssuuddoo (successful or not) will be logged,
     regardless of whether or not mail is sent.

     If ssuuddoo is run by root and the SUDO_USER environment variable is set, the
     ssuuddooeerrss policy will use this value to determine who the actual user is.
     This can be used by a user to log commands through sudo even when a root
     shell has been invoked.  It also allows the --ee option to remain useful
     even when invoked via a sudo-run script or program.  Note, however, that
     the _s_u_d_o_e_r_s file lookup is still done for root, not the user specified by
     SUDO_USER.

     ssuuddooeerrss uses per-user time stamp files for credential caching.  Once a
     user has been authenticated, a record is written containing the user ID
     that was used to authenticate, the terminal session ID, the start time of
     the session leader (or parent process) and a time stamp (using a
     monotonic clock if one is available).  The user may then use ssuuddoo without
     a password for a short period of time (5 minutes unless overridden by the
     _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t option).  By default, ssuuddooeerrss uses a separate record
     for each terminal, which means that a user's login sessions are
     authenticated separately.  The _t_i_m_e_s_t_a_m_p___t_y_p_e option can be used to
     select the type of time stamp record ssuuddooeerrss will use.

   LLooggggiinngg
     ssuuddooeerrss can log both successful and unsuccessful attempts (as well as
     errors) to syslog(3), a log file, or both.  By default, ssuuddooeerrss will log
     via syslog(3) but this is changeable via the _s_y_s_l_o_g and _l_o_g_f_i_l_e Defaults
     settings.  See _L_O_G _F_O_R_M_A_T for a description of the log file format.

     ssuuddooeerrss is also capable of running a command in a pseudo-tty and logging
     all input and/or output.  The standard input, standard output and
     standard error can be logged even when not associated with a terminal.
     I/O logging is not on by default but can be enabled using the _l_o_g___i_n_p_u_t
     and _l_o_g___o_u_t_p_u_t options as well as the LOG_INPUT and LOG_OUTPUT command
     tags.  See _I_/_O _L_O_G _F_I_L_E_S for details on how I/O log files are stored.

   CCoommmmaanndd eennvviirroonnmmeenntt
     Since environment variables can influence program behavior, ssuuddooeerrss
     provides a means to restrict which variables from the user's environment
     are inherited by the command to be run.  There are two distinct ways
     ssuuddooeerrss can deal with environment variables.

     By default, the _e_n_v___r_e_s_e_t option is enabled.  This causes commands to be
     executed with a new, minimal environment.  On AIX (and Linux systems
     without PAM), the environment is initialized with the contents of the
     _/_e_t_c_/_e_n_v_i_r_o_n_m_e_n_t file.  On BSD systems, if the _u_s_e___l_o_g_i_n_c_l_a_s_s option is
     enabled, the environment is initialized based on the _p_a_t_h and _s_e_t_e_n_v
     settings in _/_e_t_c_/_l_o_g_i_n_._c_o_n_f.  The new environment contains the TERM,
     PATH, HOME, MAIL, SHELL, LOGNAME, USER and SUDO_* variables in addition
     to variables from the invoking process permitted by the _e_n_v___c_h_e_c_k and
     _e_n_v___k_e_e_p options.  This is effectively a whitelist for environment
     variables.  The environment variables LOGNAME and USER are treated
     specially.  If one of them is preserved (or removed) from user's
     environment, the other will be as well.  If LOGNAME and USER are to be
     preserved but only one of them is present in the user's environment, the
     other will be set to the same value.  This avoids an inconsistent
     environment where one of the variables describing the user name is set to
     the invoking user and one is set to the target user.  () are removed
     unless both the name and value parts are matched by _e_n_v___k_e_e_p or
     _e_n_v___c_h_e_c_k, as they may be interpreted as functions by the bbaasshh shell.
     Prior to version 1.8.11, such variables were always removed.

     If, however, the _e_n_v___r_e_s_e_t option is disabled, any variables not
     explicitly denied by the _e_n_v___c_h_e_c_k and _e_n_v___d_e_l_e_t_e options are inherited
     from the invoking process.  In this case, _e_n_v___c_h_e_c_k and _e_n_v___d_e_l_e_t_e behave
     like a blacklist.  Prior to version 1.8.21, environment variables with a
     value beginning with () were always removed.  Beginning with version
     1.8.21, a pattern in _e_n_v___d_e_l_e_t_e is used to match bbaasshh shell functions
     instead.  Since it is not possible to blacklist all potentially dangerous
     environment variables, use of the default _e_n_v___r_e_s_e_t behavior is
     encouraged.

     Environment variables specified by _e_n_v___c_h_e_c_k, _e_n_v___d_e_l_e_t_e, or _e_n_v___k_e_e_p may
     include one or more `*' characters which will match zero or more
     characters.  No other wildcard characters are supported.

     By default, environment variables are matched by name.  However, if the
     pattern includes an equal sign (`='), both the variables name and value
     must match.  For example, a bbaasshh shell function could be matched as
     follows:

         env_keep += "BASH_FUNC_my_func%%=()*"

     Without the "=()*" suffix, this would not match, as bbaasshh shell functions
     are not preserved by default.

     The complete list of environment variables that ssuuddoo allows or denies is
     contained in the output of "sudo -V" when run as root.  Please note that
     this list varies based on the operating system ssuuddoo is running on.

     On systems that support PAM where the ppaamm__eennvv module is enabled for ssuuddoo,
     variables in the PAM environment may be merged in to the environment.  If
     a variable in the PAM environment is already present in the user's
     environment, the value will only be overridden if the variable was not
     preserved by ssuuddooeerrss.  When _e_n_v___r_e_s_e_t is enabled, variables preserved
     from the invoking user's environment by the _e_n_v___k_e_e_p list take precedence
     over those in the PAM environment.  When _e_n_v___r_e_s_e_t is disabled, variables
     present the invoking user's environment take precedence over those in the
     PAM environment unless they match a pattern in the _e_n_v___d_e_l_e_t_e list.

     Note that the dynamic linker on most operating systems will remove
     variables that can control dynamic linking from the environment of setuid
     executables, including ssuuddoo.  Depending on the operating system this may
     include _RLD*, DYLD_*, LD_*, LDR_*, LIBPATH, SHLIB_PATH, and others.
     These type of variables are removed from the environment before ssuuddoo even
     begins execution and, as such, it is not possible for ssuuddoo to preserve
     them.

     As a special case, if ssuuddoo's --ii option (initial login) is specified,
     ssuuddooeerrss will initialize the environment regardless of the value of
     _e_n_v___r_e_s_e_t.  The DISPLAY, PATH and TERM variables remain unchanged; HOME,
     MAIL, SHELL, USER, and LOGNAME are set based on the target user.  On AIX
     (and Linux systems without PAM), the contents of _/_e_t_c_/_e_n_v_i_r_o_n_m_e_n_t are
     also included.  On BSD systems, if the _u_s_e___l_o_g_i_n_c_l_a_s_s flag is enabled,
     the _p_a_t_h and _s_e_t_e_n_v variables in _/_e_t_c_/_l_o_g_i_n_._c_o_n_f are also applied.  All
     other environment variables are removed unless permitted by _e_n_v___k_e_e_p or
     _e_n_v___c_h_e_c_k, described above.

     Finally, the _r_e_s_t_r_i_c_t_e_d___e_n_v___f_i_l_e and _e_n_v___f_i_l_e files are applied, if
     present.  The variables in _r_e_s_t_r_i_c_t_e_d___e_n_v___f_i_l_e are applied first and are
     subject to the same restrictions as the invoking user's environment, as
     detailed above.  The variables in _e_n_v___f_i_l_e are applied last and are not
     subject to these restrictions.  In both cases, variables present in the
     files will only be set to their specified values if they would not
     conflict with an existing environment variable.

SSUUDDOOEERRSS FFIILLEE FFOORRMMAATT
     The _s_u_d_o_e_r_s file is composed of two types of entries: aliases (basically
     variables) and user specifications (which specify who may run what).

     When multiple entries match for a user, they are applied in order.  Where
     there are multiple matches, the last match is used (which is not
     necessarily the most specific match).

     The _s_u_d_o_e_r_s file grammar will be described below in Extended Backus-Naur
     Form (EBNF).  Don't despair if you are unfamiliar with EBNF; it is fairly
     simple, and the definitions below are annotated.

   QQuuiicckk gguuiiddee ttoo EEBBNNFF
     EBNF is a concise and exact way of describing the grammar of a language.
     Each EBNF definition is made up of _p_r_o_d_u_c_t_i_o_n _r_u_l_e_s.  E.g.,

     symbol ::= definition | alternate1 | alternate2 ...

     Each _p_r_o_d_u_c_t_i_o_n _r_u_l_e references others and thus makes up a grammar for
     the language.  EBNF also contains the following operators, which many
     readers will recognize from regular expressions.  Do not, however,
     confuse them with "wildcard" characters, which have different meanings.

     ?     Means that the preceding symbol (or group of symbols) is optional.
           That is, it may appear once or not at all.

     *     Means that the preceding symbol (or group of symbols) may appear
           zero or more times.

     +     Means that the preceding symbol (or group of symbols) may appear
           one or more times.

     Parentheses may be used to group symbols together.  For clarity, we will
     use single quotes ('') to designate what is a verbatim character string
     (as opposed to a symbol name).

   AAlliiaasseess
     There are four kinds of aliases: User_Alias, Runas_Alias, Host_Alias and
     Cmnd_Alias.

     Alias ::= 'User_Alias'  User_Alias_Spec (':' User_Alias_Spec)* |
               'Runas_Alias' Runas_Alias_Spec (':' Runas_Alias_Spec)* |
               'Host_Alias'  Host_Alias_Spec (':' Host_Alias_Spec)* |
               'Cmnd_Alias'  Cmnd_Alias_Spec (':' Cmnd_Alias_Spec)*

     User_Alias ::= NAME

     User_Alias_Spec ::= User_Alias '=' User_List

     Runas_Alias ::= NAME

     Runas_Alias_Spec ::= Runas_Alias '=' Runas_List

     Host_Alias ::= NAME

     Host_Alias_Spec ::= Host_Alias '=' Host_List

     Cmnd_Alias ::= NAME

     Cmnd_Alias_Spec ::= Cmnd_Alias '=' Cmnd_List

     NAME ::= [A-Z]([A-Z][0-9]_)*

     Each _a_l_i_a_s definition is of the form

     Alias_Type NAME = item1, item2, ...

     where _A_l_i_a_s___T_y_p_e is one of User_Alias, Runas_Alias, Host_Alias, or
     Cmnd_Alias.  A NAME is a string of uppercase letters, numbers, and
     underscore characters (`_').  A NAME mmuusstt start with an uppercase letter.
     It is possible to put several alias definitions of the same type on a
     single line, joined by a colon (`:').  E.g.,

     Alias_Type NAME = item1, item2, item3 : NAME = item4, item5

     It is a syntax error to redefine an existing _a_l_i_a_s.  It is possible to
     use the same name for _a_l_i_a_s_e_s of different types, but this is not
     recommended.

     The definitions of what constitutes a valid _a_l_i_a_s member follow.

     User_List ::= User |
                   User ',' User_List

     User ::= '!'* user name |
              '!'* #uid |
              '!'* %group |
              '!'* %#gid |
              '!'* +netgroup |
              '!'* %:nonunix_group |
              '!'* %:#nonunix_gid |
              '!'* User_Alias

     A User_List is made up of one or more user names, user IDs (prefixed with
     `#'), system group names and IDs (prefixed with `%' and `%#'
     respectively), netgroups (prefixed with `+'), non-Unix group names and
     IDs (prefixed with `%:' and `%:#' respectively) and User_Aliases. Each
     list item may be prefixed with zero or more `!' operators.  An odd number
     of `!' operators negate the value of the item; an even number just cancel
     each other out.  User netgroups are matched using the user and domain
     members only; the host member is not used when matching.

     A user name, uid, group, gid, netgroup, nonunix_group or nonunix_gid may
     be enclosed in double quotes to avoid the need for escaping special
     characters.  Alternately, special characters may be specified in escaped
     hex mode, e.g., \x20 for space.  When using double quotes, any prefix
     characters must be included inside the quotes.

     The actual nonunix_group and nonunix_gid syntax depends on the underlying
     group provider plugin.  For instance, the QAS AD plugin supports the
     following formats:

     ++oo  Group in the same domain: "%:Group Name"

     ++oo  Group in any domain: "%:Group Name@FULLY.QUALIFIED.DOMAIN"

     ++oo  Group SID: "%:S-1-2-34-5678901234-5678901234-5678901234-567"

     See _G_R_O_U_P _P_R_O_V_I_D_E_R _P_L_U_G_I_N_S for more information.

     Note that quotes around group names are optional.  Unquoted strings must
     use a backslash (`\') to escape spaces and special characters.  See _O_t_h_e_r
     _s_p_e_c_i_a_l _c_h_a_r_a_c_t_e_r_s _a_n_d _r_e_s_e_r_v_e_d _w_o_r_d_s for a list of characters that need
     to be escaped.

     Runas_List ::= Runas_Member |
                    Runas_Member ',' Runas_List

     Runas_Member ::= '!'* user name |
                      '!'* #uid |
                      '!'* %group |
                      '!'* %#gid |
                      '!'* %:nonunix_group |
                      '!'* %:#nonunix_gid |
                      '!'* +netgroup |
                      '!'* Runas_Alias

     A Runas_List is similar to a User_List except that instead of
     User_Aliases it can contain Runas_Aliases.  Note that user names and
     groups are matched as strings.  In other words, two users (groups) with
     the same uid (gid) are considered to be distinct.  If you wish to match
     all user names with the same uid (e.g., root and toor), you can use a uid
     instead (#0 in the example given).

     Host_List ::= Host |
                   Host ',' Host_List

     Host ::= '!'* host name |
              '!'* ip_addr |
              '!'* network(/netmask)? |
              '!'* +netgroup |
              '!'* Host_Alias

     A Host_List is made up of one or more host names, IP addresses, network
     numbers, netgroups (prefixed with `+') and other aliases.  Again, the
     value of an item may be negated with the `!' operator.  Host netgroups
     are matched using the host (both qualified and unqualified) and domain
     members only; the user member is not used when matching.  If you specify
     a network number without a netmask, ssuuddoo will query each of the local
     host's network interfaces and, if the network number corresponds to one
     of the hosts's network interfaces, will use the netmask of that
     interface.  The netmask may be specified either in standard IP address
     notation (e.g., 255.255.255.0 or ffff:ffff:ffff:ffff::), or CIDR notation
     (number of bits, e.g., 24 or 64).  A host name may include shell-style
     wildcards (see the _W_i_l_d_c_a_r_d_s section below), but unless the host name
     command on your machine returns the fully qualified host name, you'll
     need to use the _f_q_d_n option for wildcards to be useful.  Note that ssuuddoo
     only inspects actual network interfaces; this means that IP address
     127.0.0.1 (localhost) will never match.  Also, the host name "localhost"
     will only match if that is the actual host name, which is usually only
     the case for non-networked systems.

     digest ::= [A-Fa-f0-9]+ |
                [[A-Za-z0-9+/=]+

     Digest_Spec ::= "sha224" ':' digest |
                     "sha256" ':' digest |
                     "sha384" ':' digest |
                     "sha512" ':' digest

     Cmnd_List ::= Cmnd |
                   Cmnd ',' Cmnd_List

     command name ::= file name |
                      file name args |
                      file name '""'

     Cmnd ::= Digest_Spec? '!'* command name |
              '!'* directory |
              '!'* "sudoedit" |
              '!'* Cmnd_Alias

     A Cmnd_List is a list of one or more command names, directories, and
     other aliases.  A command name is a fully qualified file name which may
     include shell-style wildcards (see the _W_i_l_d_c_a_r_d_s section below).  A
     simple file name allows the user to run the command with any arguments
     he/she wishes.  However, you may also specify command line arguments
     (including wildcards).  Alternately, you can specify "" to indicate that
     the command may only be run wwiitthhoouutt command line arguments.  A directory
     is a fully qualified path name ending in a `/'.  When you specify a
     directory in a Cmnd_List, the user will be able to run any file within
     that directory (but not in any sub-directories therein).

     If a Cmnd has associated command line arguments, then the arguments in
     the Cmnd must match exactly those given by the user on the command line
     (or match the wildcards if there are any).  Note that the following
     characters must be escaped with a `\' if they are used in command
     arguments: `,', `:', `=', `\'.  The built-in command "sudoedit" is used
     to permit a user to run ssuuddoo with the --ee option (or as ssuuddooeeddiitt).  It may
     take command line arguments just as a normal command does.  Note that
     "sudoedit" is a command built into ssuuddoo itself and must be specified in
     the _s_u_d_o_e_r_s file without a leading path.

     If a command name is prefixed with a Digest_Spec, the command will only
     match successfully if it can be verified using the specified SHA-2
     digest.  The following digest formats are supported: sha224, sha256,
     sha384 and sha512.  The string may be specified in either hex or base64
     format (base64 is more compact).  There are several utilities capable of
     generating SHA-2 digests in hex format such as openssl, shasum,
     sha224sum, sha256sum, sha384sum, sha512sum.

     For example, using openssl:

     $ openssl dgst -sha224 /bin/ls
     SHA224(/bin/ls)= 118187da8364d490b4a7debbf483004e8f3e053ec954309de2c41a25

     It is also possible to use openssl to generate base64 output:

     $ openssl dgst -binary -sha224 /bin/ls | openssl base64
     EYGH2oNk1JC0p9679IMATo8+BT7JVDCd4sQaJQ==

     Warning, if the user has write access to the command itself (directly or
     via a ssuuddoo command), it may be possible for the user to replace the
     command after the digest check has been performed but before the command
     is executed.  A similar race condition exists on systems that lack the
     fexecve(2) system call when the directory in which the command is located
     is writable by the user.  See the description of the _f_d_e_x_e_c setting for
     more information on how ssuuddoo executes commands that have an associated
     digest.

     Command digests are only supported by version 1.8.7 or higher.

   DDeeffaauullttss
     Certain configuration options may be changed from their default values at
     run-time via one or more Default_Entry lines.  These may affect all users
     on any host, all users on a specific host, a specific user, a specific
     command, or commands being run as a specific user.  Note that per-command
     entries may not include command line arguments.  If you need to specify
     arguments, define a Cmnd_Alias and reference that instead.

     Default_Type ::= 'Defaults' |
                      'Defaults' '@' Host_List |
                      'Defaults' ':' User_List |
                      'Defaults' '!' Cmnd_List |
                      'Defaults' '>' Runas_List

     Default_Entry ::= Default_Type Parameter_List

     Parameter_List ::= Parameter |
                        Parameter ',' Parameter_List

     Parameter ::= Parameter '=' Value |
                   Parameter '+=' Value |
                   Parameter '-=' Value |
                   '!'* Parameter

     Parameters may be ffllaaggss, iinntteeggeerr values, ssttrriinnggss, or lliissttss.  Flags are
     implicitly boolean and can be turned off via the `!' operator.  Some
     integer, string and list parameters may also be used in a boolean context
     to disable them.  Values may be enclosed in double quotes ("") when they
     contain multiple words.  Special characters may be escaped with a
     backslash (`\').

     Lists have two additional assignment operators, += and -=.  These
     operators are used to add to and delete from a list respectively.  It is
     not an error to use the -= operator to remove an element that does not
     exist in a list.

     Defaults entries are parsed in the following order: generic, host, user
     and runas Defaults first, then command defaults.  If there are multiple
     Defaults settings of the same type, the last matching setting is used.
     The following Defaults settings are parsed before all others since they
     may affect subsequent entries: _f_q_d_n, _g_r_o_u_p___p_l_u_g_i_n, _r_u_n_a_s___d_e_f_a_u_l_t,
     _s_u_d_o_e_r_s___l_o_c_a_l_e.

     See _S_U_D_O_E_R_S _O_P_T_I_O_N_S for a list of supported Defaults parameters.

   UUsseerr ssppeecciiffiiccaattiioonn
     User_Spec ::= User_List Host_List '=' Cmnd_Spec_List \
                   (':' Host_List '=' Cmnd_Spec_List)*

     Cmnd_Spec_List ::= Cmnd_Spec |
                        Cmnd_Spec ',' Cmnd_Spec_List

     Cmnd_Spec ::= Runas_Spec? Option_Spec* Tag_Spec* Cmnd

     Runas_Spec ::= '(' Runas_List? (':' Runas_List)? ')'

     Option_Spec ::= (SELinux_Spec | Solaris_Priv_Spec | Date_Spec | Timeout_Spec)

     SELinux_Spec ::= ('ROLE=role' | 'TYPE=type')

     Solaris_Priv_Spec ::= ('PRIVS=privset' | 'LIMITPRIVS=privset')

     Date_Spec ::= ('NOTBEFORE=timestamp' | 'NOTAFTER=timestamp')

     Timeout_Spec ::= 'TIMEOUT=timeout'

     Tag_Spec ::= ('EXEC:' | 'NOEXEC:' | 'FOLLOW:' | 'NOFOLLOW' |
                   'LOG_INPUT:' | 'NOLOG_INPUT:' | 'LOG_OUTPUT:' |
                   'NOLOG_OUTPUT:' | 'MAIL:' | 'NOMAIL:' | 'PASSWD:' |
                   'NOPASSWD:' | 'SETENV:' | 'NOSETENV:')

     A uusseerr ssppeecciiffiiccaattiioonn determines which commands a user may run (and as
     what user) on specified hosts.  By default, commands are run as rroooott, but
     this can be changed on a per-command basis.

     The basic structure of a user specification is "who where = (as_whom)
     what".  Let's break that down into its constituent parts:

   RRuunnaass__SSppeecc
     A Runas_Spec determines the user and/or the group that a command may be
     run as.  A fully-specified Runas_Spec consists of two Runas_Lists (as
     defined above) separated by a colon (`:') and enclosed in a set of
     parentheses.  The first Runas_List indicates which users the command may
     be run as via ssuuddoo's --uu option.  The second defines a list of groups that
     can be specified via ssuuddoo's --gg option in addition to any of the target
     user's groups.  If both Runas_Lists are specified, the command may be run
     with any combination of users and groups listed in their respective
     Runas_Lists. If only the first is specified, the command may be run as
     any user in the list but no --gg option may be specified.  If the first
     Runas_List is empty but the second is specified, the command may be run
     as the invoking user with the group set to any listed in the Runas_List.
     If both Runas_Lists are empty, the command may only be run as the
     invoking user.  If no Runas_Spec is specified the command may be run as
     rroooott and no group may be specified.

     A Runas_Spec sets the default for the commands that follow it.  What this
     means is that for the entry:

     dgb     boulder = (operator) /bin/ls, /bin/kill, /usr/bin/lprm

     The user ddggbb may run _/_b_i_n_/_l_s, _/_b_i_n_/_k_i_l_l, and _/_u_s_r_/_b_i_n_/_l_p_r_m on the host
     boulder--but only as ooppeerraattoorr.  E.g.,

     $ sudo -u operator /bin/ls

     It is also possible to override a Runas_Spec later on in an entry.  If we
     modify the entry like so:

     dgb     boulder = (operator) /bin/ls, (root) /bin/kill, /usr/bin/lprm

     Then user ddggbb is now allowed to run _/_b_i_n_/_l_s as ooppeerraattoorr, but _/_b_i_n_/_k_i_l_l
     and _/_u_s_r_/_b_i_n_/_l_p_r_m as rroooott.

     We can extend this to allow ddggbb to run /bin/ls with either the user or
     group set to ooppeerraattoorr:

     dgb     boulder = (operator : operator) /bin/ls, (root) /bin/kill,\
             /usr/bin/lprm

     Note that while the group portion of the Runas_Spec permits the user to
     run as command with that group, it does not force the user to do so.  If
     no group is specified on the command line, the command will run with the
     group listed in the target user's password database entry.  The following
     would all be permitted by the sudoers entry above:

     $ sudo -u operator /bin/ls
     $ sudo -u operator -g operator /bin/ls
     $ sudo -g operator /bin/ls

     In the following example, user ttccmm may run commands that access a modem
     device file with the dialer group.

     tcm     boulder = (:dialer) /usr/bin/tip, /usr/bin/cu,\
             /usr/local/bin/minicom

     Note that in this example only the group will be set, the command still
     runs as user ttccmm.  E.g.

     $ sudo -g dialer /usr/bin/cu

     Multiple users and groups may be present in a Runas_Spec, in which case
     the user may select any combination of users and groups via the --uu and --gg
     options.  In this example:

     alan    ALL = (root, bin : operator, system) ALL

     user aallaann may run any command as either user root or bin, optionally
     setting the group to operator or system.

   OOppttiioonn__SSppeecc
     A Cmnd may have zero or more options associated with it.  Options may
     consist of SELinux roles and/or types, Solaris privileges sets, start
     and/or end dates and command timeouts.  Once an option is set for a Cmnd,
     subsequent Cmnds in the Cmnd_Spec_List, inherit that option unless it is
     overridden by another option.

   SSEELLiinnuuxx__SSppeecc
     On systems with SELinux support, _s_u_d_o_e_r_s file entries may optionally have
     an SELinux role and/or type associated with a command.  If a role or type
     is specified with the command it will override any default values
     specified in _s_u_d_o_e_r_s.  A role or type specified on the command line,
     however, will supersede the values in _s_u_d_o_e_r_s.

   SSoollaarriiss__PPrriivv__SSppeecc
     On Solaris systems, _s_u_d_o_e_r_s file entries may optionally specify Solaris
     privilege set and/or limit privilege set associated with a command.  If
     privileges or limit privileges are specified with the command it will
     override any default values specified in _s_u_d_o_e_r_s.

     A privilege set is a comma-separated list of privilege names.  The
     ppriv(1) command can be used to list all privileges known to the system.
     For example:

     $ ppriv -l

     In addition, there are several "special" privilege strings:

     none      the empty set

     all       the set of all privileges

     zone      the set of all privileges available in the current zone

     basic     the default set of privileges normal users are granted at login
               time

     Privileges can be excluded from a set by prefixing the privilege name
     with either an `!' or `-' character.

   DDaattee__SSppeecc
     ssuuddooeerrss rules can be specified with a start and end date via the
     NOTBEFORE and NOTAFTER settings.  The time stamp must be specified in
     _G_e_n_e_r_a_l_i_z_e_d _T_i_m_e as defined by RFC 4517.  The format is effectively
     yyyymmddHHMMSSZ where the minutes and seconds are optional.  The `Z'
     suffix indicates that the time stamp is in Coordinated Universal Time
     (UTC).  It is also possible to specify a timezone offset from UTC in
     hours and minutes instead of a `Z'.  For example, `-0500' would
     correspond to Eastern Standard time in the US.  As an extension, if no
     `Z' or timezone offset is specified, local time will be used.

     The following are all valid time stamps:

         20170214083000Z
         2017021408Z
         20160315220000-0500
         20151201235900

   TTiimmeeoouutt__SSppeecc
     A command may have a timeout associated with it.  If the timeout expires
     before the command has exited, the command will be terminated.  The
     timeout may be specified in combinations of days, hours, minutes and
     seconds with a single-letter case-insensitive suffix that indicates the
     unit of time.  For example, a timeout of 7 days, 8 hours, 30 minutes and
     10 seconds would be written as 7d8h30m10s.  If a number is specified
     without a unit, seconds are assumed.  Any of the days, minutes, hours or
     seconds may be omitted.  The order must be from largest to smallest unit
     and a unit may not be specified more than once.

     The following are all _v_a_l_i_d timeout values: 7d8h30m10s, 14d, 8h30m, 600s,
     3600.  The following are _i_n_v_a_l_i_d timeout values: 12m2w1d, 30s10m4h,
     1d2d3h.

     This option is only supported by version 1.8.20 or higher.

   TTaagg__SSppeecc
     A command may have zero or more tags associated with it.  The following
     tag values are supported: EXEC, NOEXEC, FOLLOW, NOFOLLOW, LOG_INPUT,
     NOLOG_INPUT, LOG_OUTPUT, NOLOG_OUTPUT, MAIL, NOMAIL, PASSWD, NOPASSWD,
     SETENV, and NOSETENV.  Once a tag is set on a Cmnd, subsequent Cmnds in
     the Cmnd_Spec_List, inherit the tag unless it is overridden by the
     opposite tag (in other words, PASSWD overrides NOPASSWD and NOEXEC
     overrides EXEC).

     _E_X_E_C and _N_O_E_X_E_C

       If ssuuddoo has been compiled with _n_o_e_x_e_c support and the underlying
       operating system supports it, the NOEXEC tag can be used to prevent a
       dynamically-linked executable from running further commands itself.

       In the following example, user aaaarroonn may run _/_u_s_r_/_b_i_n_/_m_o_r_e and
       _/_u_s_r_/_b_i_n_/_v_i but shell escapes will be disabled.

       aaron   shanty = NOEXEC: /usr/bin/more, /usr/bin/vi

       See the _P_r_e_v_e_n_t_i_n_g _s_h_e_l_l _e_s_c_a_p_e_s section below for more details on how
       NOEXEC works and whether or not it will work on your system.

     _F_O_L_L_O_W and _N_O_F_O_L_L_O_W Starting with version 1.8.15, ssuuddooeeddiitt will not open
       a file that is a symbolic link unless the _s_u_d_o_e_d_i_t___f_o_l_l_o_w option is
       enabled.  The _F_O_L_L_O_W and _N_O_F_O_L_L_O_W tags override the value of
       _s_u_d_o_e_d_i_t___f_o_l_l_o_w and can be used to permit (or deny) the editing of
       symbolic links on a per-command basis.  These tags are only effective
       for the _s_u_d_o_e_d_i_t command and are ignored for all other commands.

     _L_O_G___I_N_P_U_T and _N_O_L_O_G___I_N_P_U_T

       These tags override the value of the _l_o_g___i_n_p_u_t option on a per-command
       basis.  For more information, see the description of _l_o_g___i_n_p_u_t in the
       _S_U_D_O_E_R_S _O_P_T_I_O_N_S section below.

     _L_O_G___O_U_T_P_U_T and _N_O_L_O_G___O_U_T_P_U_T

       These tags override the value of the _l_o_g___o_u_t_p_u_t option on a per-command
       basis.  For more information, see the description of _l_o_g___o_u_t_p_u_t in the
       _S_U_D_O_E_R_S _O_P_T_I_O_N_S section below.

     _M_A_I_L and _N_O_M_A_I_L

       These tags provide fine-grained control over whether mail will be sent
       when a user runs a command by overriding the value of the
       _m_a_i_l___a_l_l___c_m_n_d_s option on a per-command basis.  They have no effect when
       ssuuddoo is run with the --ll or --vv options.  A _N_O_M_A_I_L tag will also override
       the _m_a_i_l___a_l_w_a_y_s and _m_a_i_l___n_o___p_e_r_m_s options.  For more information, see
       the descriptions of _m_a_i_l___a_l_l___c_m_n_d_s, _m_a_i_l___a_l_w_a_y_s, and _m_a_i_l___n_o___p_e_r_m_s in
       the _S_U_D_O_E_R_S _O_P_T_I_O_N_S section below.

     _P_A_S_S_W_D and _N_O_P_A_S_S_W_D

       By default, ssuuddoo requires that a user authenticate him or herself
       before running a command.  This behavior can be modified via the
       NOPASSWD tag.  Like a Runas_Spec, the NOPASSWD tag sets a default for
       the commands that follow it in the Cmnd_Spec_List.  Conversely, the
       PASSWD tag can be used to reverse things.  For example:

       ray     rushmore = NOPASSWD: /bin/kill, /bin/ls, /usr/bin/lprm

       would allow the user rraayy to run _/_b_i_n_/_k_i_l_l, _/_b_i_n_/_l_s, and _/_u_s_r_/_b_i_n_/_l_p_r_m
       as rroooott on the machine rushmore without authenticating himself.  If we
       only want rraayy to be able to run _/_b_i_n_/_k_i_l_l without a password the entry
       would be:

       ray     rushmore = NOPASSWD: /bin/kill, PASSWD: /bin/ls, /usr/bin/lprm

       Note, however, that the PASSWD tag has no effect on users who are in
       the group specified by the _e_x_e_m_p_t___g_r_o_u_p option.

       By default, if the NOPASSWD tag is applied to any of the entries for a
       user on the current host, he or she will be able to run "sudo -l"
       without a password.  Additionally, a user may only run "sudo -v"
       without a password if the NOPASSWD tag is present for all a user's
       entries that pertain to the current host.  This behavior may be
       overridden via the _v_e_r_i_f_y_p_w and _l_i_s_t_p_w options.

     _S_E_T_E_N_V and _N_O_S_E_T_E_N_V

       These tags override the value of the _s_e_t_e_n_v option on a per-command
       basis.  Note that if SETENV has been set for a command, the user may
       disable the _e_n_v___r_e_s_e_t option from the command line via the --EE option.
       Additionally, environment variables set on the command line are not
       subject to the restrictions imposed by _e_n_v___c_h_e_c_k, _e_n_v___d_e_l_e_t_e, or
       _e_n_v___k_e_e_p.  As such, only trusted users should be allowed to set
       variables in this manner.  If the command matched is AALLLL, the SETENV
       tag is implied for that command; this default may be overridden by use
       of the NOSETENV tag.

   WWiillddccaarrddss
     ssuuddoo allows shell-style _w_i_l_d_c_a_r_d_s (aka meta or glob characters) to be
     used in host names, path names and command line arguments in the _s_u_d_o_e_r_s
     file.  Wildcard matching is done via the glob(3) and fnmatch(3) functions
     as specified by IEEE Std 1003.1 ("POSIX.1").

     *         Matches any set of zero or more characters (including white
               space).

     ?         Matches any single character (including white space).

     [...]     Matches any character in the specified range.

     [!...]    Matches any character _n_o_t in the specified range.

     \x        For any character `x', evaluates to `x'.  This is used to
               escape special characters such as: `*', `?', `[', and `]'.

     NNoottee tthhaatt tthheessee aarree nnoott rreegguullaarr eexxpprreessssiioonnss..  Unlike a regular expression
     there is no way to match one or more characters within a range.

     Character classes may be used if your system's glob(3) and fnmatch(3)
     functions support them.  However, because the `:' character has special
     meaning in _s_u_d_o_e_r_s, it must be escaped.  For example:

         /bin/ls [[\:alpha\:]]*

     Would match any file name beginning with a letter.

     Note that a forward slash (`/') will _n_o_t be matched by wildcards used in
     the file name portion of the command.  This is to make a path like:

         /usr/bin/*

     match _/_u_s_r_/_b_i_n_/_w_h_o but not _/_u_s_r_/_b_i_n_/_X_1_1_/_x_t_e_r_m.

     When matching the command line arguments, however, a slash _d_o_e_s get
     matched by wildcards since command line arguments may contain arbitrary
     strings and not just path names.

     WWiillddccaarrddss iinn ccoommmmaanndd lliinnee aarrgguummeennttss sshhoouulldd bbee uusseedd wwiitthh ccaarree..
     Command line arguments are matched as a single, concatenated string.
     This mean a wildcard character such as `?' or `*' will match across word
     boundaries, which may be unexpected.  For example, while a sudoers entry
     like:

         %operator ALL = /bin/cat /var/log/messages*

     will allow command like:

         $ sudo cat /var/log/messages.1

     It will also allow:

         $ sudo cat /var/log/messages /etc/shadow

     which is probably not what was intended.  In most cases it is better to
     do command line processing outside of the _s_u_d_o_e_r_s file in a scripting
     language.

   EExxcceeppttiioonnss ttoo wwiillddccaarrdd rruulleess
     The following exceptions apply to the above rules:

     ""        If the empty string "" is the only command line argument in the
               _s_u_d_o_e_r_s file entry it means that command is not allowed to be
               run with _a_n_y arguments.

     sudoedit  Command line arguments to the _s_u_d_o_e_d_i_t built-in command should
               always be path names, so a forward slash (`/') will not be
               matched by a wildcard.

   IInncclluuddiinngg ootthheerr ffiilleess ffrroomm wwiitthhiinn ssuuddooeerrss
     It is possible to include other _s_u_d_o_e_r_s files from within the _s_u_d_o_e_r_s
     file currently being parsed using the #include and #includedir
     directives.

     This can be used, for example, to keep a site-wide _s_u_d_o_e_r_s file in
     addition to a local, per-machine file.  For the sake of this example the
     site-wide _s_u_d_o_e_r_s file will be _/_e_t_c_/_s_u_d_o_e_r_s and the per-machine one will
     be _/_e_t_c_/_s_u_d_o_e_r_s_._l_o_c_a_l.  To include _/_e_t_c_/_s_u_d_o_e_r_s_._l_o_c_a_l from within
     _/_e_t_c_/_s_u_d_o_e_r_s we would use the following line in _/_e_t_c_/_s_u_d_o_e_r_s:

         #include /etc/sudoers.local

     When ssuuddoo reaches this line it will suspend processing of the current
     file (_/_e_t_c_/_s_u_d_o_e_r_s) and switch to _/_e_t_c_/_s_u_d_o_e_r_s_._l_o_c_a_l.  Upon reaching the
     end of _/_e_t_c_/_s_u_d_o_e_r_s_._l_o_c_a_l, the rest of _/_e_t_c_/_s_u_d_o_e_r_s will be processed.
     Files that are included may themselves include other files.  A hard limit
     of 128 nested include files is enforced to prevent include file loops.

     If the path to the include file is not fully-qualified (does not begin
     with a `/'), it must be located in the same directory as the sudoers file
     it was included from.  For example, if _/_e_t_c_/_s_u_d_o_e_r_s contains the line:

         #include sudoers.local

     the file that will be included is _/_e_t_c_/_s_u_d_o_e_r_s_._l_o_c_a_l.

     The file name may also include the %h escape, signifying the short form
     of the host name.  In other words, if the machine's host name is
     "xerxes", then

         #include /etc/sudoers.%h

     will cause ssuuddoo to include the file _/_e_t_c_/_s_u_d_o_e_r_s_._x_e_r_x_e_s.

     The #includedir directive can be used to create a _s_u_d_o_e_r_s_._d directory
     that the system package manager can drop _s_u_d_o_e_r_s file rules into as part
     of package installation.  For example, given:

         #includedir /etc/sudoers.d

     ssuuddoo will suspend processing of the current file and read each file in
     _/_e_t_c_/_s_u_d_o_e_r_s_._d, skipping file names that end in `~' or contain a `.'
     character to avoid causing problems with package manager or editor
     temporary/backup files.  Files are parsed in sorted lexical order.  That
     is, _/_e_t_c_/_s_u_d_o_e_r_s_._d_/_0_1___f_i_r_s_t will be parsed before
     _/_e_t_c_/_s_u_d_o_e_r_s_._d_/_1_0___s_e_c_o_n_d.  Be aware that because the sorting is lexical,
     not numeric, _/_e_t_c_/_s_u_d_o_e_r_s_._d_/_1___w_h_o_o_p_s would be loaded _a_f_t_e_r
     _/_e_t_c_/_s_u_d_o_e_r_s_._d_/_1_0___s_e_c_o_n_d.  Using a consistent number of leading zeroes in
     the file names can be used to avoid such problems.  After parsing the
     files in the directory, control returns to the file that contained the
     #includedir directive.

     Note that unlike files included via #include, vviissuuddoo will not edit the
     files in a #includedir directory unless one of them contains a syntax
     error.  It is still possible to run vviissuuddoo with the --ff flag to edit the
     files directly, but this will not catch the redefinition of an _a_l_i_a_s that
     is also present in a different file.

   OOtthheerr ssppeecciiaall cchhaarraacctteerrss aanndd rreesseerrvveedd wwoorrddss
     The pound sign (`#') is used to indicate a comment (unless it is part of
     a #include directive or unless it occurs in the context of a user name
     and is followed by one or more digits, in which case it is treated as a
     uid).  Both the comment character and any text after it, up to the end of
     the line, are ignored.

     The reserved word AALLLL is a built-in _a_l_i_a_s that always causes a match to
     succeed.  It can be used wherever one might otherwise use a Cmnd_Alias,
     User_Alias, Runas_Alias, or Host_Alias.  You should not try to define
     your own _a_l_i_a_s called AALLLL as the built-in alias will be used in
     preference to your own.  Please note that using AALLLL can be dangerous
     since in a command context, it allows the user to run _a_n_y command on the
     system.

     An exclamation point (`!') can be used as a logical _n_o_t operator in a
     list or _a_l_i_a_s as well as in front of a Cmnd.  This allows one to exclude
     certain values.  For the `!' operator to be effective, there must be
     something for it to exclude.  For example, to match all users except for
     root one would use:

         ALL,!root

     If the AALLLL, is omitted, as in:

         !root

     it would explicitly deny root but not match any other users.  This is
     different from a true "negation" operator.

     Note, however, that using a `!' in conjunction with the built-in AALLLL
     alias to allow a user to run "all but a few" commands rarely works as
     intended (see _S_E_C_U_R_I_T_Y _N_O_T_E_S below).

     Long lines can be continued with a backslash (`\') as the last character
     on the line.

     White space between elements in a list as well as special syntactic
     characters in a _U_s_e_r _S_p_e_c_i_f_i_c_a_t_i_o_n (`=', `:', `(', `)') is optional.

     The following characters must be escaped with a backslash (`\') when used
     as part of a word (e.g., a user name or host name): `!', `=', `:', `,',
     `(', `)', `\'.

SSUUDDOOEERRSS OOPPTTIIOONNSS
     ssuuddoo's behavior can be modified by Default_Entry lines, as explained
     earlier.  A list of all supported Defaults parameters, grouped by type,
     are listed below.

     BBoooolleeaann FFllaaggss:

     always_query_group_plugin
                       If a _g_r_o_u_p___p_l_u_g_i_n is configured, use it to resolve
                       groups of the form %group as long as there is not also
                       a system group of the same name.  Normally, only groups
                       of the form %:group are passed to the _g_r_o_u_p___p_l_u_g_i_n.
                       This flag is _o_f_f by default.

     always_set_home   If enabled, ssuuddoo will set the HOME environment variable
                       to the home directory of the target user (which is root
                       unless the --uu option is used).  This effectively means
                       that the --HH option is always implied.  Note that by
                       default, HOME will be set to the home directory of the
                       target user when the _e_n_v___r_e_s_e_t option is enabled, so
                       _a_l_w_a_y_s___s_e_t___h_o_m_e only has an effect for configurations
                       where either _e_n_v___r_e_s_e_t is disabled or HOME is present
                       in the _e_n_v___k_e_e_p list.  This flag is _o_f_f by default.

     authenticate      If set, users must authenticate themselves via a
                       password (or other means of authentication) before they
                       may run commands.  This default may be overridden via
                       the PASSWD and NOPASSWD tags.  This flag is _o_n by
                       default.

     case_insensitive_group
                       If enabled, group names in _s_u_d_o_e_r_s will be matched in a
                       case insensitive manner.  This may be necessary when
                       users are stored in LDAP or AD.  This flag is _o_n by
                       default.

     case_insensitive_user
                       If enabled, user names in _s_u_d_o_e_r_s will be matched in a
                       case insensitive manner.  This may be necessary when
                       groups are stored in LDAP or AD.  This flag is _o_n by
                       default.

     closefrom_override
                       If set, the user may use ssuuddoo's --CC option which
                       overrides the default starting point at which ssuuddoo
                       begins closing open file descriptors.  This flag is _o_f_f
                       by default.

     compress_io       If set, and ssuuddoo is configured to log a command's input
                       or output, the I/O logs will be compressed using zzlliibb.
                       This flag is _o_n by default when ssuuddoo is compiled with
                       zzlliibb support.

     exec_background   By default, ssuuddoo runs a command as the foreground
                       process as long as ssuuddoo itself is running in the
                       foreground.  When the _e_x_e_c___b_a_c_k_g_r_o_u_n_d flag is enabled
                       and the command is being run in a pty (due to I/O
                       logging or the _u_s_e___p_t_y flag), 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 ssuuddoo 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 ssuuddoo 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 _s_u_d_o behavior
                       or when the command is not being run in a pty.

                       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 ttccggeettaattttrr() and
                       ttccsseettaattttrr() 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.  This flag
                       is _o_f_f by default.

                       This setting is only supported by version 1.8.7 or
                       higher.  It has no effect unless I/O logging is enabled
                       or the _u_s_e___p_t_y flag is enabled.

     env_editor        If set, vviissuuddoo will use the value of the SUDO_EDITOR,
                       VISUAL or EDITOR environment variables before falling
                       back on the default editor list.  Note that this may
                       create a security hole as it allows the user to run any
                       arbitrary command as root without logging.  A safer
                       alternative is to place a colon-separated list of
                       editors in the _e_d_i_t_o_r variable.  vviissuuddoo will then only
                       use SUDO_EDITOR, VISUAL or EDITOR if they match a value
                       specified in _e_d_i_t_o_r.  If the _e_n_v___r_e_s_e_t flag is enabled,
                       the SUDO_EDITOR, VISUAL and/or EDITOR environment
                       variables must be present in the _e_n_v___k_e_e_p list for the
                       _e_n_v___e_d_i_t_o_r flag to function when vviissuuddoo is invoked via
                       ssuuddoo.  This flag is _o_f_f by default.

     env_reset         If set, ssuuddoo will run the command in a minimal
                       environment containing the TERM, PATH, HOME, MAIL,
                       SHELL, LOGNAME, USER and SUDO_* variables.  Any
                       variables in the caller's environment or in the file
                       specified by the _r_e_s_t_r_i_c_t_e_d___e_n_v___f_i_l_e option that match
                       the env_keep and env_check lists are then added,
                       followed by any variables present in the file specified
                       by the _e_n_v___f_i_l_e option (if any).  The contents of the
                       env_keep and env_check lists, as modified by global
                       Defaults parameters in _s_u_d_o_e_r_s, are displayed when ssuuddoo
                       is run by root with the --VV option.  If the _s_e_c_u_r_e___p_a_t_h
                       option is set, its value will be used for the PATH
                       environment variable.  This flag is _o_n by default.

     fast_glob         Normally, ssuuddoo uses the glob(3) function to do shell-
                       style globbing when matching path names.  However,
                       since it accesses the file system, glob(3) can take a
                       long time to complete for some patterns, especially
                       when the pattern references a network file system that
                       is mounted on demand (auto mounted).  The _f_a_s_t___g_l_o_b
                       option causes ssuuddoo to use the fnmatch(3) function,
                       which does not access the file system to do its
                       matching.  The disadvantage of _f_a_s_t___g_l_o_b is that it is
                       unable to match relative path names such as _._/_l_s or
                       _._._/_b_i_n_/_l_s.  This has security implications when path
                       names that include globbing characters are used with
                       the negation operator, `!', as such rules can be
                       trivially bypassed.  As such, this option should not be
                       used when the _s_u_d_o_e_r_s file contains rules that contain
                       negated path names which include globbing characters.
                       This flag is _o_f_f by default.

     fqdn              Set this flag if you want to put fully qualified host
                       names in the _s_u_d_o_e_r_s file when the local host name (as
                       returned by the hostname command) does not contain the
                       domain name.  In other words, instead of myhost you
                       would use myhost.mydomain.edu.  You may still use the
                       short form if you wish (and even mix the two).  This
                       option is only effective when the "canonical" host
                       name, as returned by the ggeettaaddddrriinnffoo() or
                       ggeetthhoossttbbyynnaammee() function, is a fully-qualified domain
                       name.  This is usually the case when the system is
                       configured to use DNS for host name resolution.

                       If the system is configured to use the _/_e_t_c_/_h_o_s_t_s file
                       in preference to DNS, the "canonical" host name may not
                       be fully-qualified.  The order that sources are queried
                       for host name resolution is usually specified in the
                       _/_e_t_c_/_n_s_s_w_i_t_c_h_._c_o_n_f, _/_e_t_c_/_n_e_t_s_v_c_._c_o_n_f, _/_e_t_c_/_h_o_s_t_._c_o_n_f,
                       or, in some cases, _/_e_t_c_/_r_e_s_o_l_v_._c_o_n_f file.  In the
                       _/_e_t_c_/_h_o_s_t_s file, the first host name of the entry is
                       considered to be the "canonical" name; subsequent names
                       are aliases that are not used by ssuuddooeerrss.  For example,
                       the following hosts file line for the machine "xyzzy"
                       has the fully-qualified domain name as the "canonical"
                       host name, and the short version as an alias.

                             192.168.1.1    xyzzy.sudo.ws xyzzy

                       If the machine's hosts file entry is not formatted
                       properly, the _f_q_d_n option will not be effective if it
                       is queried before DNS.

                       Beware that when using DNS for host name resolution,
                       turning on _f_q_d_n requires ssuuddooeerrss to make DNS lookups
                       which renders ssuuddoo unusable if DNS stops working (for
                       example if the machine is disconnected from the
                       network).  Also note that just like with the hosts
                       file, you must use the "canonical" name as DNS knows
                       it.  That is, you may not use a host alias (CNAME
                       entry) due to performance issues and the fact that
                       there is no way to get all aliases from DNS.

                       This flag is _o_f_f by default.

     ignore_audit_errors
                       Allow commands to be run even if ssuuddooeerrss cannot write
                       to the audit log.  If enabled, an audit log write
                       failure is not treated as a fatal error.  If disabled,
                       a command may only be run after the audit event is
                       successfully written.  This flag is only effective on
                       systems for which ssuuddooeerrss supports audit logging,
                       including FreeBSD, Linux, macOS and Solaris.  This flag
                       is _o_n by default.

     ignore_dot        If set, ssuuddoo will ignore "." or "" (both denoting
                       current directory) in the PATH environment variable;
                       the PATH itself is not modified.  This flag is _o_f_f by
                       default.

     ignore_iolog_errors
                       Allow commands to be run even if ssuuddooeerrss cannot write
                       to the I/O log.  If enabled, an I/O log write failure
                       is not treated as a fatal error.  If disabled, the
                       command will be terminated if the I/O log cannot be
                       written to.  This flag is _o_f_f by default.

     ignore_logfile_errors
                       Allow commands to be run even if ssuuddooeerrss cannot write
                       to the log file.  If enabled, a log file write failure
                       is not treated as a fatal error.  If disabled, a
                       command may only be run after the log file entry is
                       successfully written.  This flag only has an effect
                       when ssuuddooeerrss is configured to use file-based logging
                       via the _l_o_g_f_i_l_e option.  This flag is _o_n by default.

     ignore_local_sudoers
                       If set via LDAP, parsing of _/_e_t_c_/_s_u_d_o_e_r_s will be
                       skipped.  This is intended for Enterprises that wish to
                       prevent the usage of local sudoers files so that only
                       LDAP is used.  This thwarts the efforts of rogue
                       operators who would attempt to add roles to
                       _/_e_t_c_/_s_u_d_o_e_r_s.  When this option is present,
                       _/_e_t_c_/_s_u_d_o_e_r_s does not even need to exist.  Since this
                       option tells ssuuddoo how to behave when no specific LDAP
                       entries have been matched, this sudoOption is only
                       meaningful for the cn=defaults section.  This flag is
                       _o_f_f by default.

     ignore_unknown_defaults
                       If set, ssuuddoo will not produce a warning if it
                       encounters an unknown Defaults entry in the _s_u_d_o_e_r_s
                       file or an unknown sudoOption in LDAP.  This flag is
                       _o_f_f by default.

     insults           If set, ssuuddoo will insult users when they enter an
                       incorrect password.  This flag is _o_f_f by default.

     log_host          If set, the host name will be logged in the (non-
                       syslog) ssuuddoo log file.  This flag is _o_f_f by default.

     log_input         If set, ssuuddoo will run the command in a pseudo-tty and
                       log all user input.  If the standard input is not
                       connected to the user's tty, due to I/O redirection or
                       because the command is part of a pipeline, that input
                       is also captured and stored in a separate log file.
                       Anything sent to the standard input will be consumed,
                       regardless of whether or not the command run via ssuuddoo
                       is actually reading the standard input.  This may have
                       unexpected results when using ssuuddoo in a shell script
                       that expects to process the standard input.  For more
                       information about I/O logging, see the _I_/_O _L_O_G _F_I_L_E_S
                       section.  This flag is _o_f_f by default.

     log_output        If set, ssuuddoo will run the command in a pseudo-tty and
                       log all output that is sent to the screen, similar to
                       the script(1) command.  For more information about I/O
                       logging, see the _I_/_O _L_O_G _F_I_L_E_S section.  This flag is
                       _o_f_f by default.

     log_year          If set, the four-digit year will be logged in the (non-
                       syslog) ssuuddoo log file.  This flag is _o_f_f by default.

     long_otp_prompt   When validating with a One Time Password (OTP) scheme
                       such as SS//KKeeyy or OOPPIIEE, a two-line prompt is used to
                       make it easier to cut and paste the challenge to a
                       local window.  It's not as pretty as the default but
                       some people find it more convenient.  This flag is _o_f_f
                       by default.

     mail_all_cmnds    Send mail to the _m_a_i_l_t_o user every time a user attempts
                       to run a command via ssuuddoo (this includes ssuuddooeeddiitt).  No
                       mail will be sent if the user runs ssuuddoo with the --ll or
                       --vv option unless there is an authentication error and
                       the _m_a_i_l___b_a_d_p_a_s_s flag is also set.  This flag is _o_f_f by
                       default.

     mail_always       Send mail to the _m_a_i_l_t_o user every time a user runs
                       ssuuddoo.  This flag is _o_f_f by default.

     mail_badpass      Send mail to the _m_a_i_l_t_o user if the user running ssuuddoo
                       does not enter the correct password.  If the command
                       the user is attempting to run is not permitted by
                       ssuuddooeerrss and one of the _m_a_i_l___a_l_l___c_m_n_d_s, _m_a_i_l___a_l_w_a_y_s,
                       _m_a_i_l___n_o___h_o_s_t, _m_a_i_l___n_o___p_e_r_m_s or _m_a_i_l___n_o___u_s_e_r flags are
                       set, this flag will have no effect.  This flag is _o_f_f
                       by default.

     mail_no_host      If set, mail will be sent to the _m_a_i_l_t_o user if the
                       invoking user exists in the _s_u_d_o_e_r_s file, but is not
                       allowed to run commands on the current host.  This flag
                       is _o_f_f by default.

     mail_no_perms     If set, mail will be sent to the _m_a_i_l_t_o user if the
                       invoking user is allowed to use ssuuddoo but the command
                       they are trying is not listed in their _s_u_d_o_e_r_s file
                       entry or is explicitly denied.  This flag is _o_f_f by
                       default.

     mail_no_user      If set, mail will be sent to the _m_a_i_l_t_o user if the
                       invoking user is not in the _s_u_d_o_e_r_s file.  This flag is
                       _o_n by default.

     match_group_by_gid
                       By default, ssuuddooeerrss will look up each group the user is
                       a member of by group ID to determine the group name
                       (this is only done once).  The resulting list of the
                       user's group names is used when matching groups listed
                       in the _s_u_d_o_e_r_s file.  This works well on systems where
                       the number of groups listed in the _s_u_d_o_e_r_s file is
                       larger than the number of groups a typical user belongs
                       to.  On systems where group lookups are slow, where
                       users may belong to a large number of groups, and where
                       the number of groups listed in the _s_u_d_o_e_r_s file is
                       relatively small, it may be prohibitively expensive and
                       running commands via ssuuddoo may take longer than normal.
                       On such systems it may be faster to use the
                       _m_a_t_c_h___g_r_o_u_p___b_y___g_i_d flag to avoid resolving the user's
                       group IDs to group names.  In this case, ssuuddooeerrss must
                       look up any group name listed in the _s_u_d_o_e_r_s file and
                       use the group ID instead of the group name when
                       determining whether the user is a member of the group.

                       Note that if _m_a_t_c_h___g_r_o_u_p___b_y___g_i_d is enabled, group
                       database lookups performed by ssuuddooeerrss will be keyed by
                       group name as opposed to group ID.  On systems where
                       there are multiple sources for the group database, it
                       is possible to have conflicting group names or group
                       IDs in the local _/_e_t_c_/_g_r_o_u_p file and the remote group
                       database.  On such systems, enabling or disabling
                       _m_a_t_c_h___g_r_o_u_p___b_y___g_i_d can be used to choose whether group
                       database queries are performed by name (enabled) or ID
                       (disabled), which may aid in working around group entry
                       conflicts.

                       The _m_a_t_c_h___g_r_o_u_p___b_y___g_i_d flag has no effect when _s_u_d_o_e_r_s
                       data is stored in LDAP.  This flag is _o_f_f by default.

                       This setting is only supported by version 1.8.18 or
                       higher.

     netgroup_tuple    If set, netgroup lookups will be performed using the
                       full netgroup tuple: host name, user name and domain
                       (if one is set).  Historically, ssuuddoo only matched the
                       user name and domain for netgroups used in a User_List
                       and only matched the host name and domain for netgroups
                       used in a Host_List.  This flag is _o_f_f by default.

     noexec            If set, all commands run via ssuuddoo will behave as if the
                       NOEXEC tag has been set, unless overridden by an EXEC
                       tag.  See the description of _E_X_E_C _a_n_d _N_O_E_X_E_C above as
                       well as the _P_r_e_v_e_n_t_i_n_g _s_h_e_l_l _e_s_c_a_p_e_s section at the end
                       of this manual.  This flag is _o_f_f by default.

     pam_session       On systems that use PAM for authentication, ssuuddoo will
                       create a new PAM session for the command to be run in.
                       Disabling _p_a_m___s_e_s_s_i_o_n may be needed on older PAM
                       implementations or on operating systems where opening a
                       PAM session changes the utmp or wtmp files.  If PAM
                       session support is disabled, resource limits may not be
                       updated for the command being run.  If _p_a_m___s_e_s_s_i_o_n,
                       _p_a_m___s_e_t_c_r_e_d, and _u_s_e___p_t_y are disabled and I/O logging
                       has not been configured, ssuuddoo will execute the command
                       directly instead of running it as a child process.
                       This flag is _o_n by default.

                       This setting is only supported by version 1.8.7 or
                       higher.

     pam_setcred       On systems that use PAM for authentication, ssuuddoo will
                       attempt to establish credentials for the target user by
                       default, if supported by the underlying authentication
                       system.  One example of a credential is a Kerberos
                       ticket.  If _p_a_m___s_e_s_s_i_o_n, _p_a_m___s_e_t_c_r_e_d, and _u_s_e___p_t_y are
                       disabled and I/O logging has not been configured, ssuuddoo
                       will execute the command directly instead of running it
                       as a child process.  This flag is _o_n by default.

                       This setting is only supported by version 1.8.8 or
                       higher.

     passprompt_override
                       If set, the prompt specified by _p_a_s_s_p_r_o_m_p_t or the
                       SUDO_PROMPT environment variable will always be used
                       and will replace the prompt provided by a PAM module or
                       other authentication method.  This flag is _o_f_f by
                       default.

     path_info         Normally, ssuuddoo will tell the user when a command could
                       not be found in their PATH environment variable.  Some
                       sites may wish to disable this as it could be used to
                       gather information on the location of executables that
                       the normal user does not have access to.  The
                       disadvantage is that if the executable is simply not in
                       the user's PATH, ssuuddoo will tell the user that they are
                       not allowed to run it, which can be confusing.  This
                       flag is _o_n by default.

     preserve_groups   By default, ssuuddoo will initialize the group vector to
                       the list of groups the target user is in.  When
                       _p_r_e_s_e_r_v_e___g_r_o_u_p_s is set, the user's existing group
                       vector is left unaltered.  The real and effective group
                       IDs, however, are still set to match the target user.
                       This flag is _o_f_f by default.

     pwfeedback        By default, ssuuddoo reads the password like most other
                       Unix programs, by turning off echo until the user hits
                       the return (or enter) key.  Some users become confused
                       by this as it appears to them that ssuuddoo has hung at
                       this point.  When _p_w_f_e_e_d_b_a_c_k is set, ssuuddoo will provide
                       visual feedback when the user presses a key.  Note that
                       this does have a security impact as an onlooker may be
                       able to determine the length of the password being
                       entered.  This flag is _o_f_f by default.

     requiretty        If set, ssuuddoo will only run when the user is logged in
                       to a real tty.  When this flag is set, ssuuddoo can only be
                       run from a login session and not via other means such
                       as cron(1m) or cgi-bin scripts.  This flag is _o_f_f by
                       default.

     root_sudo         If set, root is allowed to run ssuuddoo too.  Disabling
                       this prevents users from "chaining" ssuuddoo commands to
                       get a root shell by doing something like "sudo sudo
                       /bin/sh".  Note, however, that turning off _r_o_o_t___s_u_d_o
                       will also prevent root from running ssuuddooeeddiitt.
                       Disabling _r_o_o_t___s_u_d_o provides no real additional
                       security; it exists purely for historical reasons.
                       This flag is _o_n by default.

     rootpw            If set, ssuuddoo will prompt for the root password instead
                       of the password of the invoking user when running a
                       command or editing a file.  This flag is _o_f_f by
                       default.

     runaspw           If set, ssuuddoo will prompt for the password of the user
                       defined by the _r_u_n_a_s___d_e_f_a_u_l_t option (defaults to root)
                       instead of the password of the invoking user when
                       running a command or editing a file.  This flag is _o_f_f
                       by default.

     set_home          If enabled and ssuuddoo is invoked with the --ss option the
                       HOME environment variable will be set to the home
                       directory of the target user (which is root unless the
                       --uu option is used).  This effectively makes the --ss
                       option imply --HH.  Note that HOME is already set when
                       the _e_n_v___r_e_s_e_t option is enabled, so _s_e_t___h_o_m_e is only
                       effective for configurations where either _e_n_v___r_e_s_e_t is
                       disabled or HOME is present in the _e_n_v___k_e_e_p list.  This
                       flag is _o_f_f by default.

     set_logname       Normally, ssuuddoo will set the LOGNAME and USER
                       environment variables to the name of the target user
                       (usually root unless the --uu option is given).  However,
                       since some programs (including the RCS revision control
                       system) use LOGNAME to determine the real identity of
                       the user, it may be desirable to change this behavior.
                       This can be done by negating the set_logname option.
                       Note that _s_e_t___l_o_g_n_a_m_e will have no effect if the
                       _e_n_v___r_e_s_e_t option has not been disabled and the _e_n_v___k_e_e_p
                       list contains LOGNAME or USER.  This flag is _o_n by
                       default.

     set_utmp          When enabled, ssuuddoo will create an entry in the utmp (or
                       utmpx) file when a pseudo-tty is allocated.  A pseudo-
                       tty is allocated by ssuuddoo when the _l_o_g___i_n_p_u_t, _l_o_g___o_u_t_p_u_t
                       or _u_s_e___p_t_y flags are enabled.  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.  This flag is _o_n by default.

     setenv            Allow the user to disable the _e_n_v___r_e_s_e_t option from the
                       command line via the --EE option.  Additionally,
                       environment variables set via the command line are not
                       subject to the restrictions imposed by _e_n_v___c_h_e_c_k,
                       _e_n_v___d_e_l_e_t_e, or _e_n_v___k_e_e_p.  As such, only trusted users
                       should be allowed to set variables in this manner.
                       This flag is _o_f_f by default.

     shell_noargs      If set and ssuuddoo is invoked with no arguments it acts as
                       if the --ss option had been given.  That is, it runs a
                       shell as root (the shell is determined by the SHELL
                       environment variable if it is set, falling back on the
                       shell listed in the invoking user's /etc/passwd entry
                       if not).  This flag is _o_f_f by default.

     stay_setuid       Normally, when ssuuddoo executes a command the real and
                       effective UIDs are set to the target user (root by
                       default).  This option changes that behavior such that
                       the real UID is left as the invoking user's UID.  In
                       other words, this makes ssuuddoo act as a setuid wrapper.
                       This can be useful on systems that disable some
                       potentially dangerous functionality when a program is
                       run setuid.  This option is only effective on systems
                       that support either the setreuid(2) or setresuid(2)
                       system call.  This flag is _o_f_f by default.

     sudoedit_checkdir
                       If set, ssuuddooeeddiitt 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 ssuuddooeeddiitt will refuse to edit a file
                       located in a writable directory.  These restrictions
                       are not enforced when ssuuddooeeddiitt is run by root.  On some
                       systems, if all directory components of the path to be
                       edited are not readable by the target user, ssuuddooeeddiitt
                       will be unable to edit the file.  This flag is _o_n by
                       default.

                       This setting was first introduced in version 1.8.15 but
                       initially suffered from a race condition.  The check
                       for symbolic links in writable intermediate directories
                       was added in version 1.8.16.

     sudoedit_follow   By default, ssuuddooeeddiitt will not follow symbolic links
                       when opening files.  The _s_u_d_o_e_d_i_t___f_o_l_l_o_w option can be
                       enabled to allow ssuuddooeeddiitt to open symbolic links.  It
                       may be overridden on a per-command basis by the _F_O_L_L_O_W
                       and _N_O_F_O_L_L_O_W tags.  This flag is _o_f_f by default.

                       This setting is only supported by version 1.8.15 or
                       higher.

     syslog_pid        When logging via syslog(3), include the process ID in
                       the log entry.  This flag is _o_f_f by default.

                       This setting is only supported by version 1.8.21 or
                       higher.

     targetpw          If set, ssuuddoo will prompt for the password of the user
                       specified by the --uu option (defaults to root) instead
                       of the password of the invoking user when running a
                       command or editing a file.  Note that this flag
                       precludes the use of a uid not listed in the passwd
                       database as an argument to the --uu option.  This flag is
                       _o_f_f by default.

     tty_tickets       If set, users must authenticate on a per-tty basis.
                       With this flag enabled, ssuuddoo will use a separate record
                       in the time stamp file for each terminal.  If disabled,
                       a single record is used for all login sessions.

                       This option has been superseded by the _t_i_m_e_s_t_a_m_p___t_y_p_e
                       option.

     umask_override    If set, ssuuddoo will set the umask as specified in the
                       _s_u_d_o_e_r_s file without modification.  This makes it
                       possible to specify a umask in the _s_u_d_o_e_r_s file that is
                       more permissive than the user's own umask and matches
                       historical behavior.  If _u_m_a_s_k___o_v_e_r_r_i_d_e is not set,
                       ssuuddoo will set the umask to be the union of the user's
                       umask and what is specified in _s_u_d_o_e_r_s.  This flag is
                       _o_f_f by default.

     use_loginclass    If set, ssuuddoo will apply the defaults specified for the
                       target user's login class if one exists.  Only
                       available if ssuuddoo is configured with the
                       --with-logincap option.  This flag is _o_f_f by default.

     use_netgroups     If set, netgroups (prefixed with `+'), may be used in
                       place of a user or host.  For LDAP-based sudoers,
                       netgroup support requires an expensive sub-string match
                       on the server unless the NNEETTGGRROOUUPP__BBAASSEE directive is
                       present in the _/_e_t_c_/_l_d_a_p_._c_o_n_f file.  If netgroups are
                       not needed, this option can be disabled to reduce the
                       load on the LDAP server.  This flag is _o_n by default.

     use_pty           If set, and ssuuddoo is running in a terminal, the command
                       will be run in a pseudo-pty (even if no I/O logging is
                       being done).  If the ssuuddoo process is not attached to a
                       terminal, _u_s_e___p_t_y has no effect.

                       A malicious program run under ssuuddoo may be capable of
                       injecting commands into the user's terminal or running
                       a background process that retains access to the user's
                       terminal device even after the main program has
                       finished executing.  By running the command in a
                       separate pseudo-pty, this attack is no longer possible.
                       This flag is _o_f_f by default.

     user_command_timeouts
                       If set, the user may specify a timeout on the command
                       line.  If the timeout expires before the command has
                       exited, the command will be terminated.  If a timeout
                       is specified both in the _s_u_d_o_e_r_s file and on the
                       command line, the smaller of the two timeouts will be
                       used.  See the Timeout_Spec section for a description
                       of the timeout syntax.  This flag is _o_f_f by default.

                       This setting is only supported by version 1.8.20 or
                       higher.

     utmp_runas        If set, ssuuddoo will store the name of the runas user when
                       updating the utmp (or utmpx) file.  By default, ssuuddoo
                       stores the name of the invoking user.  This flag is _o_f_f
                       by default.

     visiblepw         By default, ssuuddoo will refuse to run if the user must
                       enter a password but it is not possible to disable echo
                       on the terminal.  If the _v_i_s_i_b_l_e_p_w flag is set, ssuuddoo
                       will prompt for a password even when it would be
                       visible on the screen.  This makes it possible to run
                       things like "ssh somehost sudo ls" since by default,
                       ssh(1) does not allocate a tty when running a command.
                       This flag is _o_f_f by default.

     IInntteeggeerrss:

     closefrom         Before it executes a command, ssuuddoo will close all open
                       file descriptors other than standard input, standard
                       output and standard error (ie: file descriptors 0-2).
                       The _c_l_o_s_e_f_r_o_m option can be used to specify a different
                       file descriptor at which to start closing.  The default
                       is 3.

     command_timeout   The maximum amount of time a command is allowed to run
                       before it is terminated.  See the Timeout_Spec section
                       for a description of the timeout syntax.

                       This setting is only supported by version 1.8.20 or
                       higher.

     maxseq            The maximum sequence number that will be substituted
                       for the "%{seq}" escape in the I/O log file (see the
                       _i_o_l_o_g___d_i_r description below for more information).
                       While the value substituted for "%{seq}" is in base 36,
                       _m_a_x_s_e_q itself should be expressed in decimal.  Values
                       larger than 2176782336 (which corresponds to the base
                       36 sequence number "ZZZZZZ") will be silently truncated
                       to 2176782336.  The default value is 2176782336.

                       Once the local sequence number reaches the value of
                       _m_a_x_s_e_q, it will "roll over" to zero, after which
                       ssuuddooeerrss will truncate and re-use any existing I/O log
                       path names.

                       This setting is only supported by version 1.8.7 or
                       higher.

     passwd_tries      The number of tries a user gets to enter his/her
                       password before ssuuddoo logs the failure and exits.  The
                       default is 3.

     syslog_maxlen     On many systems, syslog(3) has a relatively small log
                       buffer.  IETF RFC 5424 states that syslog servers must
                       support messages of at least 480 bytes and should
                       support messages up to 2048 bytes.  By default, ssuuddooeerrss
                       creates log messages up to 980 bytes which corresponds
                       to the historic BSD syslog implementation which used a
                       1024 byte buffer to store the message, date, hostname
                       and program name.  To prevent syslog messages from
                       being truncated, ssuuddooeerrss will split up log messages
                       that are larger than _s_y_s_l_o_g___m_a_x_l_e_n bytes.  When a
                       message is split, additional parts will include the
                       string "(command continued)" after the user name and
                       before the continued command line arguments.

                       This setting is only supported by version 1.8.19 or
                       higher.

     IInntteeggeerrss tthhaatt ccaann bbee uusseedd iinn aa bboooolleeaann ccoonntteexxtt:

     loglinelen        Number of characters per line for the file log.  This
                       value is used to decide when to wrap lines for nicer
                       log files.  This has no effect on the syslog log file,
                       only the file log.  The default is 80 (use 0 or negate
                       the option to disable word wrap).

     passwd_timeout    Number of minutes before the ssuuddoo password prompt times
                       out, or 0 for no timeout.  The timeout may include a
                       fractional component if minute granularity is
                       insufficient, for example 2.5.  The default is 5.

     timestamp_timeout
                       Number of minutes that can elapse before ssuuddoo will ask
                       for a passwd again.  The timeout may include a
                       fractional component if minute granularity is
                       insufficient, for example 2.5.  The default is 5.  Set
                       this to 0 to always prompt for a password.  If set to a
                       value less than 0 the user's time stamp will not expire
                       until the system is rebooted.  This can be used to
                       allow users to create or delete their own time stamps
                       via "sudo -v" and "sudo -k" respectively.

     umask             Umask to use when running the command.  Negate this
                       option or set it to 0777 to preserve the user's umask.
                       The actual umask that is used will be the union of the
                       user's umask and the value of the _u_m_a_s_k option, which
                       defaults to 0022.  This guarantees that ssuuddoo never
                       lowers the umask when running a command.  Note: on
                       systems that use PAM, the default PAM configuration may
                       specify its own umask which will override the value set
                       in _s_u_d_o_e_r_s.

     SSttrriinnggss:

     authfail_message  Message that is displayed after a user fails to
                       authenticate.  The message may include the `%d' escape
                       which will expand to the number of failed password
                       attempts.  If set, it overrides the default message, %d
                       incorrect password attempt(s).

     badpass_message   Message that is displayed if a user enters an incorrect
                       password.  The default is Sorry, try again. unless
                       insults are enabled.

     editor            A colon (`:') separated list of editors path names used
                       by ssuuddooeeddiitt and vviissuuddoo.  For ssuuddooeeddiitt, this list is
                       used to find an editor when none of the SUDO_EDITOR,
                       VISUAL or EDITOR environment variables are set to an
                       editor that exists and is executable.  For vviissuuddoo, it
                       is used as a white list of allowed editors; vviissuuddoo will
                       choose the editor that matches the user's SUDO_EDITOR,
                       VISUAL or EDITOR environment variable if possible, or
                       the first editor in the list that exists and is
                       executable if not.  Unless invoked as ssuuddooeeddiitt, ssuuddoo
                       does not preserve the SUDO_EDITOR, VISUAL and EDITOR
                       environment variables by default, even when the
                       _e_n_v___r_e_s_e_t option is enabled.  The default is _v_i.

     iolog_dir         The top-level directory to use when constructing the
                       path name for the input/output log directory.  Only
                       used if the _l_o_g___i_n_p_u_t or _l_o_g___o_u_t_p_u_t options are enabled
                       or when the LOG_INPUT or LOG_OUTPUT tags are present
                       for a command.  The session sequence number, if any, is
                       stored in the directory.  The default is
                       _/_v_a_r_/_l_o_g_/_s_u_d_o_-_i_o.

                       The following percent (`%') escape sequences are
                       supported:

                       %{seq}
                             expanded to a monotonically increasing base-36
                             sequence number, such as 0100A5, where every two
                             digits are used to form a new directory, e.g.,
                             _0_1_/_0_0_/_A_5

                       %{user}
                             expanded to the invoking user's login name

                       %{group}
                             expanded to the name of the invoking user's real
                             group ID

                       %{runas_user}
                             expanded to the login name of the user the
                             command will be run as (e.g., root)

                       %{runas_group}
                             expanded to the group name of the user the
                             command will be run as (e.g., wheel)

                       %{hostname}
                             expanded to the local host name without the
                             domain name

                       %{command}
                             expanded to the base name of the command being
                             run

                       In addition, any escape sequences supported by the
                       system's strftime(3) function will be expanded.

                       To include a literal `%' character, the string `%%'
                       should be used.

     iolog_file        The path name, relative to _i_o_l_o_g___d_i_r, in which to store
                       input/output logs when the _l_o_g___i_n_p_u_t or _l_o_g___o_u_t_p_u_t
                       options are enabled or when the LOG_INPUT or LOG_OUTPUT
                       tags are present for a command.  Note that _i_o_l_o_g___f_i_l_e
                       may contain directory components.  The default is
                       "%{seq}".

                       See the _i_o_l_o_g___d_i_r option above for a list of supported
                       percent (`%') escape sequences.

                       In addition to the escape sequences, path names that
                       end in six or more Xs will have the Xs replaced with a
                       unique combination of digits and letters, similar to
                       the mktemp(3) function.

                       If the path created by concatenating _i_o_l_o_g___d_i_r and
                       _i_o_l_o_g___f_i_l_e already exists, the existing I/O log file
                       will be truncated and overwritten unless _i_o_l_o_g___f_i_l_e
                       ends in six or more Xs.

     iolog_flush       If set, ssuuddoo will flush I/O log data to disk after each
                       write instead of buffering it.  This makes it possible
                       to view the logs in real-time as the program is
                       executing but may significantly reduce the
                       effectiveness of I/O log compression.  This flag is _o_f_f
                       by default.

                       This setting is only supported by version 1.8.20 or
                       higher.

     iolog_group       The group name to look up when setting the group ID on
                       new I/O log files and directories.  If _i_o_l_o_g___g_r_o_u_p is
                       not set, the primary group ID of the user specified by
                       _i_o_l_o_g___u_s_e_r is used.  If neither _i_o_l_o_g___g_r_o_u_p nor
                       _i_o_l_o_g___u_s_e_r are set, I/O log files and directories are
                       created with group ID 0.

                       This setting is only supported by version 1.8.19 or
                       higher.

     iolog_mode        The file mode to use when creating I/O log files.  Mode
                       bits for read and write permissions for owner, group or
                       other are honored, everything else is ignored.  The
                       file permissions will always include the owner read and
                       write bits, even if they are not present in the
                       specified mode.  When creating I/O log directories,
                       search (execute) bits are added to match the read and
                       write bits specified by _i_o_l_o_g___m_o_d_e.  Defaults to 0600
                       (read and write by user only).

                       This setting is only supported by version 1.8.19 or
                       higher.

     iolog_user        The user name to look up when setting the user and
                       group IDs on new I/O log files and directories.  If
                       _i_o_l_o_g___g_r_o_u_p is set, it will be used instead of the
                       user's primary group ID.  By default, I/O log files and
                       directories are created with user and group ID 0.

                       This setting can be useful when the I/O logs are stored
                       on a Network File System (NFS) share.  Having a
                       dedicated user own the I/O log files means that ssuuddooeerrss
                       does not write to the log files as user ID 0, which is
                       usually not permitted by NFS.

                       This setting is only supported by version 1.8.19 or
                       higher.

     lecture_status_dir
                       The directory in which ssuuddoo stores per-user lecture
                       status files.  Once a user has received the lecture, a
                       zero-length file is created in this directory so that
                       ssuuddoo will not lecture the user again.  This directory
                       should _n_o_t be cleared when the system reboots.  The
                       default is _/_v_a_r_/_a_d_m_/_s_u_d_o_/_l_e_c_t_u_r_e_d.

     limitprivs        The default Solaris limit privileges to use when
                       constructing a new privilege set for a command.  This
                       bounds all privileges of the executing process.  The
                       default limit privileges may be overridden on a per-
                       command basis in _s_u_d_o_e_r_s.  This option is only
                       available if ssuuddooeerrss is built on Solaris 10 or higher.

     mailsub           Subject of the mail sent to the _m_a_i_l_t_o user.  The
                       escape %h will expand to the host name of the machine.
                       Default is "*** SECURITY information for %h ***".

     noexec_file       As of ssuuddoo version 1.8.1 this option is no longer
                       supported.  The path to the noexec file should now be
                       set in the sudo.conf(4) file.

     pam_login_service
                       On systems that use PAM for authentication, this is the
                       service name used when the --ii option is specified.  The
                       default value is "sudo".  See the description of
                       _p_a_m___s_e_r_v_i_c_e for more information.

                       This setting is only supported by version 1.8.8 or
                       higher.

     pam_service       On systems that use PAM for authentication, the service
                       name specifies the PAM policy to apply.  This usually
                       corresponds to an entry in the _p_a_m_._c_o_n_f file or a file
                       in the _/_e_t_c_/_p_a_m_._d directory.  The default value is
                       "sudo".

                       This setting is only supported by version 1.8.8 or
                       higher.

     passprompt        The default prompt to use when asking for a password;
                       can be overridden via the --pp option or the SUDO_PROMPT
                       environment variable.  The following percent (`%')
                       escape sequences are supported:

                       %H    expanded to the local host name including the
                             domain name (only if the machine's host name is
                             fully qualified or the _f_q_d_n option is set)

                       %h    expanded to the local host name without the
                             domain name

                       %p    expanded to the user whose password is being
                             asked for (respects the _r_o_o_t_p_w, _t_a_r_g_e_t_p_w and
                             _r_u_n_a_s_p_w flags in _s_u_d_o_e_r_s)

                       %U    expanded to the login name of the user the
                             command will be run as (defaults to root)

                       %u    expanded to the invoking user's login name

                       %%    two consecutive % characters are collapsed into a
                             single % character

                       On systems that use PAM for authentication, _p_a_s_s_p_r_o_m_p_t
                       will only be used if the prompt provided by the PAM
                       module matches the string "Password: " or "username's
                       Password: ".  This ensures that the _p_a_s_s_p_r_o_m_p_t setting
                       does not interfere with challenge-response style
                       authentication.  The _p_a_s_s_p_r_o_m_p_t___o_v_e_r_r_i_d_e flag can be
                       used to change this behavior.

                       The default value is "Password: ".

     privs             The default Solaris privileges to use when constructing
                       a new privilege set for a command.  This is passed to
                       the executing process via the inherited privilege set,
                       but is bounded by the limit privileges.  If the _p_r_i_v_s
                       option is specified but the _l_i_m_i_t_p_r_i_v_s option is not,
                       the limit privileges of the executing process is set to
                       _p_r_i_v_s.  The default privileges may be overridden on a
                       per-command basis in _s_u_d_o_e_r_s.  This option is only
                       available if ssuuddooeerrss is built on Solaris 10 or higher.

     role              The default SELinux role to use when constructing a new
                       security context to run the command.  The default role
                       may be overridden on a per-command basis in the _s_u_d_o_e_r_s
                       file or via command line options.  This option is only
                       available when ssuuddoo is built with SELinux support.

     runas_default     The default user to run commands as if the --uu option is
                       not specified on the command line.  This defaults to
                       root.

     sudoers_locale    Locale to use when parsing the sudoers file, logging
                       commands, and sending email.  Note that changing the
                       locale may affect how sudoers is interpreted.  Defaults
                       to "C".

     timestamp_type    ssuuddooeerrss uses per-user time stamp files for credential
                       caching.  The _t_i_m_e_s_t_a_m_p___t_y_p_e option can be used to
                       specify the type of time stamp record used.  It has the
                       following possible values:

                       global  A single time stamp record is used for all of a
                               user's login sessions, regardless of the
                               terminal or parent process ID.  An additional
                               record is used to serialize password prompts
                               when ssuuddoo is used multiple times in a pipeline,
                               but this does not affect authentication.

                       ppid    A single time stamp record is used for all
                               processes with the same parent process ID
                               (usually the shell).  Commands run from the
                               same shell (or other common parent process)
                               will not require a password for
                               _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t minutes (5 by default).
                               Commands run via ssuuddoo with a different parent
                               process ID, for example from a shell script,
                               will be authenticated separately.

                       tty     One time stamp record is used for each
                               terminal, which means that a user's login
                               sessions are authenticated separately.  If no
                               terminal is present, the behavior is the same
                               as _p_p_i_d.  Commands run from the same terminal
                               will not require a password for
                               _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t minutes (5 by default).

                       kernel  The time stamp is stored in the kernel as an
                               attribute of the terminal device.  If no
                               terminal is present, the behavior is the same
                               as _p_p_i_d.  Negative _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t values are
                               not supported and positive values are limited
                               to a maximum of 60 minutes.  This is currently
                               only supported on OpenBSD.

                       The default value is _t_t_y.

                       This setting is only supported by version 1.8.21 or
                       higher.

     timestampdir      The directory in which ssuuddoo stores its time stamp
                       files.  This directory should be cleared when the
                       system reboots.  The default is _/_v_a_r_/_r_u_n_/_s_u_d_o_/_t_s.

     timestampowner    The owner of the lecture status directory, time stamp
                       directory and all files stored therein.  The default is
                       root.

     type              The default SELinux type to use when constructing a new
                       security context to run the command.  The default type
                       may be overridden on a per-command basis in the _s_u_d_o_e_r_s
                       file or via command line options.  This option is only
                       available when ssuuddoo is built with SELinux support.

     SSttrriinnggss tthhaatt ccaann bbee uusseedd iinn aa bboooolleeaann ccoonntteexxtt:

     env_file      The _e_n_v___f_i_l_e option specifies the fully qualified path to a
                   file containing variables to be set in the environment of
                   the program being run.  Entries in this file should either
                   be of the form "VARIABLE=value" or "export VARIABLE=value".
                   The value may optionally be surrounded by single or double
                   quotes.  Variables in this file are only added if the
                   variable does not already exist in the environment.  This
                   file is considered to be part of the security policy, its
                   contents are not subject to other ssuuddoo environment
                   restrictions such as _e_n_v___k_e_e_p and _e_n_v___c_h_e_c_k.

     exempt_group  Users in this group are exempt from password and PATH
                   requirements.  The group name specified should not include
                   a % prefix.  This is not set by default.

     fdexec        Determines whether ssuuddoo will execute a command by its path
                   or by an open file descriptor.  It has the following
                   possible values:

                   always  Always execute by file descriptor.

                   never   Never execute by file descriptor.

                   digest_only
                           Only execute by file descriptor if the command has
                           an associated digest in the _s_u_d_o_e_r_s file.

                   The default value is _d_i_g_e_s_t___o_n_l_y.  This avoids a time of
                   check versus time of use race condition when the command is
                   located in a directory writable by the invoking user.

                   Note that _f_d_e_x_e_c will change the first element of the
                   argument vector for scripts ($0 in the shell) due to the
                   way the kernel runs script interpreters.  Instead of being
                   a normal path, it will refer to a file descriptor.  For
                   example, _/_d_e_v_/_f_d_/_4 on Solaris and _/_p_r_o_c_/_s_e_l_f_/_f_d_/_4 on Linux.
                   A workaround is to use the SUDO_COMMAND environment
                   variable instead.

                   The _f_d_e_x_e_c setting is only used when the command is matched
                   by path name.  It has no effect if the command is matched
                   by the built-in AALLLL alias.

                   This setting is only supported by version 1.8.20 or higher.
                   If the operating system does not support the fexecve(2)
                   system call, this setting has no effect.

     group_plugin  A string containing a ssuuddooeerrss group plugin with optional
                   arguments.  The string should consist of the plugin path,
                   either fully-qualified or relative to the
                   _/_u_s_r_/_l_o_c_a_l_/_l_i_b_e_x_e_c_/_s_u_d_o directory, followed by any
                   configuration arguments the plugin requires.  These
                   arguments (if any) will be passed to the plugin's
                   initialization function.  If arguments are present, the
                   string must be enclosed in double quotes ("").

                   For more information see _G_R_O_U_P _P_R_O_V_I_D_E_R _P_L_U_G_I_N_S.

     lecture       This option controls when a short lecture will be printed
                   along with the password prompt.  It has the following
                   possible values:

                   always  Always lecture the user.

                   never   Never lecture the user.

                   once    Only lecture the user the first time they run ssuuddoo.

                   If no value is specified, a value of _o_n_c_e is implied.
                   Negating the option results in a value of _n_e_v_e_r being used.
                   The default value is _o_n_c_e.

     lecture_file  Path to a file containing an alternate ssuuddoo lecture that
                   will be used in place of the standard lecture if the named
                   file exists.  By default, ssuuddoo uses a built-in lecture.

     listpw        This option controls when a password will be required when
                   a user runs ssuuddoo with the --ll option.  It has the following
                   possible values:

                   all       All the user's _s_u_d_o_e_r_s file entries for the
                             current host must have the NOPASSWD flag set to
                             avoid entering a password.

                   always    The user must always enter a password to use the
                             --ll option.

                   any       At least one of the user's _s_u_d_o_e_r_s file entries
                             for the current host must have the NOPASSWD flag
                             set to avoid entering a password.

                   never     The user need never enter a password to use the
                             --ll option.

                   If no value is specified, a value of _a_n_y is implied.
                   Negating the option results in a value of _n_e_v_e_r being used.
                   The default value is _a_n_y.

     logfile       Path to the ssuuddoo log file (not the syslog log file).
                   Setting a path turns on logging to a file; negating this
                   option turns it off.  By default, ssuuddoo logs via syslog.

     mailerflags   Flags to use when invoking mailer.  Defaults to --tt.

     mailerpath    Path to mail program used to send warning mail.  Defaults
                   to the path to sendmail found at configure time.

     mailfrom      Address to use for the "from" address when sending warning
                   and error mail.  The address should be enclosed in double
                   quotes ("") to protect against ssuuddoo interpreting the @
                   sign.  Defaults to the name of the user running ssuuddoo.

     mailto        Address to send warning and error mail to.  The address
                   should be enclosed in double quotes ("") to protect against
                   ssuuddoo interpreting the @ sign.  Defaults to root.

     restricted_env_file
                   The _r_e_s_t_r_i_c_t_e_d___e_n_v___f_i_l_e option specifies the fully
                   qualified path to a file containing variables to be set in
                   the environment of the program being run.  Entries in this
                   file should either be of the form "VARIABLE=value" or
                   "export VARIABLE=value".  The value may optionally be
                   surrounded by single or double quotes.  Variables in this
                   file are only added if the variable does not already exist
                   in the environment.  Unlike _e_n_v___f_i_l_e, the file's contents
                   are not trusted and are processed in a manner similar to
                   that of the invoking user's environment.  If _e_n_v___r_e_s_e_t is
                   enabled, variables in the file will only be added if they
                   are matched by either the _e_n_v___c_h_e_c_k or _e_n_v___k_e_e_p list.  If
                   _e_n_v___r_e_s_e_t is disabled, variables in the file are added as
                   long as they are not matched by the _e_n_v___d_e_l_e_t_e list.  In
                   either case, the contents of _r_e_s_t_r_i_c_t_e_d___e_n_v___f_i_l_e are
                   processed before the contents of _e_n_v___f_i_l_e.

     secure_path   Path used for every command run from ssuuddoo.  If you don't
                   trust the people running ssuuddoo to have a sane PATH
                   environment variable you may want to use this.  Another use
                   is if you want to have the "root path" be separate from the
                   "user path".  Users in the group specified by the
                   _e_x_e_m_p_t___g_r_o_u_p option are not affected by _s_e_c_u_r_e___p_a_t_h.  This
                   option is not set by default.

     syslog        Syslog facility if syslog is being used for logging (negate
                   to disable syslog logging).  Defaults to auth.

                   The following syslog facilities are supported: aauutthhpprriivv (if
                   your OS supports it), aauutthh, ddaaeemmoonn, uusseerr, llooccaall00, llooccaall11,
                   llooccaall22, llooccaall33, llooccaall44, llooccaall55, llooccaall66, and llooccaall77.

     syslog_badpri
                   Syslog priority to use when the user is not allowed to run
                   a command or when authentication is unsuccessful.  Defaults
                   to alert.

                   The following syslog priorities are supported: aalleerrtt, ccrriitt,
                   ddeebbuugg, eemmeerrgg, eerrrr, iinnffoo, nnoottiiccee, wwaarrnniinngg, and nnoonnee.
                   Negating the option or setting it to a value of nnoonnee will
                   disable logging of unsuccessful commands.

     syslog_goodpri
                   Syslog priority to use when the user is allowed to run a
                   command and authentication is successful.  Defaults to
                   notice.

                   See _s_y_s_l_o_g___b_a_d_p_r_i for the list of supported syslog
                   priorities.  Negating the option or setting it to a value
                   of nnoonnee will disable logging of successful commands.

     verifypw      This option controls when a password will be required when
                   a user runs ssuuddoo with the --vv option.  It has the following
                   possible values:

                   all     All the user's _s_u_d_o_e_r_s file entries for the current
                           host must have the NOPASSWD flag set to avoid
                           entering a password.

                   always  The user must always enter a password to use the --vv
                           option.

                   any     At least one of the user's _s_u_d_o_e_r_s file entries for
                           the current host must have the NOPASSWD flag set to
                           avoid entering a password.

                   never   The user need never enter a password to use the --vv
                           option.

                   If no value is specified, a value of _a_l_l is implied.
                   Negating the option results in a value of _n_e_v_e_r being used.
                   The default value is _a_l_l.

     LLiissttss tthhaatt ccaann bbee uusseedd iinn aa bboooolleeaann ccoonntteexxtt:

     env_check         Environment variables to be removed from the user's
                       environment unless they are considered "safe".  For all
                       variables except TZ, "safe" means that the variable's
                       value does not contain any `%' or `/' characters.  This
                       can be used to guard against printf-style format
                       vulnerabilities in poorly-written programs.  The TZ
                       variable is considered unsafe if any of the following
                       are true:

                       ++oo  It consists of a fully-qualified path name,
                          optionally prefixed with a colon (`:'), that does
                          not match the location of the _z_o_n_e_i_n_f_o directory.

                       ++oo  It contains a _._. path element.

                       ++oo  It contains white space or non-printable characters.

                       ++oo  It is longer than the value of PATH_MAX.

                       The argument may be a double-quoted, space-separated
                       list or a single value without double-quotes.  The list
                       can be replaced, added to, deleted from, or disabled by
                       using the =, +=, -=, and ! operators respectively.
                       Regardless of whether the env_reset option is enabled
                       or disabled, variables specified by env_check will be
                       preserved in the environment if they pass the
                       aforementioned check.  The global list of environment
                       variables to check is displayed when ssuuddoo is run by
                       root with the --VV option.

     env_delete        Environment variables to be removed from the user's
                       environment when the _e_n_v___r_e_s_e_t option is not in effect.
                       The argument may be a double-quoted, space-separated
                       list or a single value without double-quotes.  The list
                       can be replaced, added to, deleted from, or disabled by
                       using the =, +=, -=, and ! operators respectively.  The
                       global list of environment variables to remove is
                       displayed when ssuuddoo is run by root with the --VV option.
                       Note that many operating systems will remove
                       potentially dangerous variables from the environment of
                       any setuid process (such as ssuuddoo).

     env_keep          Environment variables to be preserved in the user's
                       environment when the _e_n_v___r_e_s_e_t option is in effect.
                       This allows fine-grained control over the environment
                       ssuuddoo-spawned processes will receive.  The argument may
                       be a double-quoted, space-separated list or a single
                       value without double-quotes.  The list can be replaced,
                       added to, deleted from, or disabled by using the =, +=,
                       -=, and ! operators respectively.  The global list of
                       variables to keep is displayed when ssuuddoo is run by root
                       with the --VV option.

GGRROOUUPP PPRROOVVIIDDEERR PPLLUUGGIINNSS
     The ssuuddooeerrss plugin supports its own plugin interface to allow non-Unix
     group lookups which can query a group source other than the standard Unix
     group database.  This can be used to implement support for the
     nonunix_group syntax described earlier.

     Group provider plugins are specified via the _g_r_o_u_p___p_l_u_g_i_n Defaults
     setting.  The argument to _g_r_o_u_p___p_l_u_g_i_n should consist of the plugin path,
     either fully-qualified or relative to the _/_u_s_r_/_l_o_c_a_l_/_l_i_b_e_x_e_c_/_s_u_d_o
     directory, followed by any configuration options the plugin requires.
     These options (if specified) will be passed to the plugin's
     initialization function.  If options are present, the string must be
     enclosed in double quotes ("").

     The following group provider plugins are installed by default:

     group_file
               The _g_r_o_u_p___f_i_l_e plugin supports an alternate group file that
               uses the same syntax as the _/_e_t_c_/_g_r_o_u_p file.  The path to the
               group file should be specified as an option to the plugin.  For
               example, if the group file to be used is _/_e_t_c_/_s_u_d_o_-_g_r_o_u_p:

               Defaults group_plugin="group_file.so /etc/sudo-group"

     system_group
               The _s_y_s_t_e_m___g_r_o_u_p plugin supports group lookups via the standard
               C library functions ggeettggrrnnaamm() and ggeettggrriidd().  This plugin can
               be used in instances where the user belongs to groups not
               present in the user's supplemental group vector.  This plugin
               takes no options:

               Defaults group_plugin=system_group.so

     The group provider plugin API is described in detail in sudo_plugin(4).

LLOOGG FFOORRMMAATT
     ssuuddooeerrss can log events using either syslog(3) or a simple log file.  The
     log format is almost identical in both cases.

   AAcccceepptteedd ccoommmmaanndd lloogg eennttrriieess
     Commands that sudo runs are logged using the following format (split into
     multiple lines for readability):

         date hostname progname: username : TTY=ttyname ; PWD=cwd ; \
             USER=runasuser ; GROUP=runasgroup ; TSID=logid ; \
             ENV=env_vars COMMAND=command

     Where the fields are as follows:

     date          The date the command was run.  Typically, this is in the
                   format "MMM, DD, HH:MM:SS".  If logging via syslog(3), the
                   actual date format is controlled by the syslog daemon.  If
                   logging to a file and the _l_o_g___y_e_a_r option is enabled, the
                   date will also include the year.

     hostname      The name of the host ssuuddoo was run on.  This field is only
                   present when logging via syslog(3).

     progname      The name of the program, usually _s_u_d_o or _s_u_d_o_e_d_i_t.  This
                   field is only present when logging via syslog(3).

     username      The login name of the user who ran ssuuddoo.

     ttyname       The short name of the terminal (e.g., "console", "tty01",
                   or "pts/0") ssuuddoo was run on, or "unknown" if there was no
                   terminal present.

     cwd           The current working directory that ssuuddoo was run in.

     runasuser     The user the command was run as.

     runasgroup    The group the command was run as if one was specified on
                   the command line.

     logid         An I/O log identifier that can be used to replay the
                   command's output.  This is only present when the _l_o_g___i_n_p_u_t
                   or _l_o_g___o_u_t_p_u_t option is enabled.

     env_vars      A list of environment variables specified on the command
                   line, if specified.

     command       The actual command that was executed.

     Messages are logged using the locale specified by _s_u_d_o_e_r_s___l_o_c_a_l_e, which
     defaults to the "C" locale.

   DDeenniieedd ccoommmmaanndd lloogg eennttrriieess
     If the user is not allowed to run the command, the reason for the denial
     will follow the user name.  Possible reasons include:

     user NOT in sudoers
        The user is not listed in the _s_u_d_o_e_r_s file.

     user NOT authorized on host
        The user is listed in the _s_u_d_o_e_r_s file but is not allowed to run
        commands on the host.

     command not allowed
        The user is listed in the _s_u_d_o_e_r_s file for the host but they are not
        allowed to run the specified command.

     3 incorrect password attempts
        The user failed to enter their password after 3 tries.  The actual
        number of tries will vary based on the number of failed attempts and
        the value of the _p_a_s_s_w_d___t_r_i_e_s option.

     a password is required
        ssuuddoo's --nn option was specified but a password was required.

     sorry, you are not allowed to set the following environment variables
        The user specified environment variables on the command line that were
        not allowed by _s_u_d_o_e_r_s.

   EErrrroorr lloogg eennttrriieess
     If an error occurs, ssuuddooeerrss will log a message and, in most cases, send a
     message to the administrator via email.  Possible errors include:

     parse error in /etc/sudoers near line N
        ssuuddooeerrss encountered an error when parsing the specified file.  In some
        cases, the actual error may be one line above or below the line number
        listed, depending on the type of error.

     problem with defaults entries
        The _s_u_d_o_e_r_s file contains one or more unknown Defaults settings.  This
        does not prevent ssuuddoo from running, but the _s_u_d_o_e_r_s file should be
        checked using vviissuuddoo.

     timestamp owner (username): No such user
        The time stamp directory owner, as specified by the _t_i_m_e_s_t_a_m_p_o_w_n_e_r
        setting, could not be found in the password database.

     unable to open/read /etc/sudoers
        The _s_u_d_o_e_r_s file could not be opened for reading.  This can happen
        when the _s_u_d_o_e_r_s file is located on a remote file system that maps
        user ID 0 to a different value.  Normally, ssuuddooeerrss tries to open the
        _s_u_d_o_e_r_s file using group permissions to avoid this problem.  Consider
        either changing the ownership of _/_e_t_c_/_s_u_d_o_e_r_s or adding an argument
        like "sudoers_uid=N" (where `N' is the user ID that owns the _s_u_d_o_e_r_s
        file) to the end of the ssuuddooeerrss Plugin line in the sudo.conf(4) file.

     unable to stat /etc/sudoers
        The _/_e_t_c_/_s_u_d_o_e_r_s file is missing.

     /etc/sudoers is not a regular file
        The _/_e_t_c_/_s_u_d_o_e_r_s file exists but is not a regular file or symbolic
        link.

     /etc/sudoers is owned by uid N, should be 0
        The _s_u_d_o_e_r_s file has the wrong owner.  If you wish to change the
        _s_u_d_o_e_r_s file owner, please add "sudoers_uid=N" (where `N' is the user
        ID that owns the _s_u_d_o_e_r_s file) to the ssuuddooeerrss Plugin line in the
        sudo.conf(4) file.

     /etc/sudoers is world writable
        The permissions on the _s_u_d_o_e_r_s file allow all users to write to it.
        The _s_u_d_o_e_r_s file must not be world-writable, the default file mode is
        0440 (readable by owner and group, writable by none).  The default
        mode may be changed via the "sudoers_mode" option to the ssuuddooeerrss
        Plugin line in the sudo.conf(4) file.

     /etc/sudoers is owned by gid N, should be 1
        The _s_u_d_o_e_r_s file has the wrong group ownership.  If you wish to change
        the _s_u_d_o_e_r_s file group ownership, please add "sudoers_gid=N" (where
        `N' is the group ID that owns the _s_u_d_o_e_r_s file) to the ssuuddooeerrss Plugin
        line in the sudo.conf(4) file.

     unable to open /var/run/sudo/ts/username
        ssuuddooeerrss was unable to read or create the user's time stamp file.  This
        can happen when _t_i_m_e_s_t_a_m_p_o_w_n_e_r is set to a user other than root and
        the mode on _/_v_a_r_/_r_u_n_/_s_u_d_o is not searchable by group or other.  The
        default mode for _/_v_a_r_/_r_u_n_/_s_u_d_o is 0711.

     unable to write to /var/run/sudo/ts/username
        ssuuddooeerrss was unable to write to the user's time stamp file.

     /var/run/sudo/ts is owned by uid X, should be Y
        The time stamp directory is owned by a user other than _t_i_m_e_s_t_a_m_p_o_w_n_e_r.
        This can occur when the value of _t_i_m_e_s_t_a_m_p_o_w_n_e_r has been changed.
        ssuuddooeerrss will ignore the time stamp directory until the owner is
        corrected.

     /var/run/sudo/ts is group writable
        The time stamp directory is group-writable; it should be writable only
        by _t_i_m_e_s_t_a_m_p_o_w_n_e_r.  The default mode for the time stamp directory is
        0700.  ssuuddooeerrss will ignore the time stamp directory until the mode is
        corrected.

   NNootteess oonn llooggggiinngg vviiaa ssyysslloogg
     By default, ssuuddooeerrss logs messages via syslog(3).  The _d_a_t_e, _h_o_s_t_n_a_m_e, and
     _p_r_o_g_n_a_m_e fields are added by the system's ssyysslloogg() function, not ssuuddooeerrss
     itself.  As such, they may vary in format on different systems.

     The maximum size of syslog messages varies from system to system.  The
     _s_y_s_l_o_g___m_a_x_l_e_n setting can be used to change the maximum syslog message
     size from the default value of 980 bytes.  For more information, see the
     description of _s_y_s_l_o_g___m_a_x_l_e_n.

   NNootteess oonn llooggggiinngg ttoo aa ffiillee
     If the _l_o_g_f_i_l_e option is set, ssuuddooeerrss will log to a local file, such as
     _/_v_a_r_/_l_o_g_/_s_u_d_o.  When logging to a file, ssuuddooeerrss uses a format similar to
     syslog(3), with a few important differences:

     1.   The _p_r_o_g_n_a_m_e and _h_o_s_t_n_a_m_e fields are not present.

     2.   If the _l_o_g___y_e_a_r option is enabled, the date will also include the
          year.

     3.   Lines that are longer than _l_o_g_l_i_n_e_l_e_n characters (80 by default) are
          word-wrapped and continued on the next line with a four character
          indent.  This makes entries easier to read for a human being, but
          makes it more difficult to use grep(1) on the log files.  If the
          _l_o_g_l_i_n_e_l_e_n option is set to 0 (or negated with a `!'), word wrap
          will be disabled.

II//OO LLOOGG FFIILLEESS
     When I/O logging is enabled, ssuuddoo will run the command in a pseudo-tty
     and log all user input and/or output, depending on which options are
     enabled.  I/O is logged to the directory specified by the _i_o_l_o_g___d_i_r
     option (_/_v_a_r_/_l_o_g_/_s_u_d_o_-_i_o by default) using a unique session ID that is
     included in the ssuuddoo log line, prefixed with "TSID=".  The _i_o_l_o_g___f_i_l_e
     option may be used to control the format of the session ID.

     Each I/O log is stored in a separate directory that contains the
     following files:

     _l_o_g       a text file containing the time the command was run, the name
               of the user who ran ssuuddoo, the name of the target user, the name
               of the target group (optional), the terminal that ssuuddoo was run
               from, the number of rows and columns of the terminal, the
               working directory the command was run from and the path name of
               the command itself (with arguments if present)

     _t_i_m_i_n_g    a log of the amount of time between, and the number of bytes
               in, each I/O log entry (used for session playback)

     _t_t_y_i_n     input from the user's tty (what the user types)

     _s_t_d_i_n     input from a pipe or file

     _t_t_y_o_u_t    output from the pseudo-tty (what the command writes to the
               screen)

     _s_t_d_o_u_t    standard output to a pipe or redirected to a file

     _s_t_d_e_r_r    standard error to a pipe or redirected to a file

     All files other than _l_o_g are compressed in gzip format unless the
     _c_o_m_p_r_e_s_s___i_o flag has been disabled.  Due to buffering, it is not normally
     possible to display the I/O logs in real-time as the program is executing
     The I/O log data will not be complete until the program run by ssuuddoo has
     exited or has been terminated by a signal.  The _i_o_l_o_g___f_l_u_s_h flag can be
     used to disable buffering, in which case I/O log data is written to disk
     as soon as it is available.  The output portion of an I/O log file can be
     viewed with the sudoreplay(1m) utility, which can also be used to list or
     search the available logs.

     Note that user input may contain sensitive information such as passwords
     (even if they are not echoed to the screen), which will be stored in the
     log file unencrypted.  In most cases, logging the command output via
     _l_o_g___o_u_t_p_u_t or LOG_OUTPUT is all that is required.

     Since each session's I/O logs are stored in a separate directory,
     traditional log rotation utilities cannot be used to limit the number of
     I/O logs.  The simplest way to limit the number of I/O is by setting the
     _m_a_x_s_e_q option to the maximum number of logs you wish to store.  Once the
     I/O log sequence number reaches _m_a_x_s_e_q, it will be reset to zero and
     ssuuddooeerrss will truncate and re-use any existing I/O logs.

FFIILLEESS
     _/_e_t_c_/_s_u_d_o_._c_o_n_f            Sudo front end configuration

     _/_e_t_c_/_s_u_d_o_e_r_s              List of who can run what

     _/_e_t_c_/_g_r_o_u_p                Local groups file

     _/_e_t_c_/_n_e_t_g_r_o_u_p             List of network groups

     _/_v_a_r_/_l_o_g_/_s_u_d_o_-_i_o          I/O log files

     _/_v_a_r_/_r_u_n_/_s_u_d_o_/_t_s          Directory containing time stamps for the
                               ssuuddooeerrss security policy

     _/_v_a_r_/_a_d_m_/_s_u_d_o_/_l_e_c_t_u_r_e_d    Directory containing lecture status files for
                               the ssuuddooeerrss security policy

     _/_e_t_c_/_e_n_v_i_r_o_n_m_e_n_t          Initial environment for --ii mode on AIX and
                               Linux systems

EEXXAAMMPPLLEESS
     Below are example _s_u_d_o_e_r_s file entries.  Admittedly, some of these are a
     bit contrived.  First, we allow a few environment variables to pass and
     then define our _a_l_i_a_s_e_s:

     # Run X applications through sudo; HOME is used to find the
     # .Xauthority file.  Note that other programs use HOME to find
     # configuration files and this may lead to privilege escalation!
     Defaults env_keep += "DISPLAY HOME"

     # User alias specification
     User_Alias      FULLTIMERS = millert, mikef, dowdy
     User_Alias      PARTTIMERS = bostley, jwfox, crawl
     User_Alias      WEBMASTERS = will, wendy, wim

     # Runas alias specification
     Runas_Alias     OP = root, operator
     Runas_Alias     DB = oracle, sybase
     Runas_Alias     ADMINGRP = adm, oper

     # Host alias specification
     Host_Alias      SPARC = bigtime, eclipse, moet, anchor :\
                     SGI = grolsch, dandelion, black :\
                     ALPHA = widget, thalamus, foobar :\
                     HPPA = boa, nag, python
     Host_Alias      CUNETS = 128.138.0.0/255.255.0.0
     Host_Alias      CSNETS = 128.138.243.0, 128.138.204.0/24, 128.138.242.0
     Host_Alias      SERVERS = master, mail, www, ns
     Host_Alias      CDROM = orion, perseus, hercules

     # Cmnd alias specification
     Cmnd_Alias      DUMPS = /usr/bin/mt, /usr/sbin/dump, /usr/sbin/rdump,\
                             /usr/sbin/restore, /usr/sbin/rrestore,\
                             sha224:0GomF8mNN3wlDt1HD9XldjJ3SNgpFdbjO1+NsQ== \
                             /home/operator/bin/start_backups
     Cmnd_Alias      KILL = /usr/bin/kill
     Cmnd_Alias      PRINTING = /usr/sbin/lpc, /usr/bin/lprm
     Cmnd_Alias      SHUTDOWN = /usr/sbin/shutdown
     Cmnd_Alias      HALT = /usr/sbin/halt
     Cmnd_Alias      REBOOT = /usr/sbin/reboot
     Cmnd_Alias      SHELLS = /usr/bin/sh, /usr/bin/csh, /usr/bin/ksh,\
                              /usr/local/bin/tcsh, /usr/bin/rsh,\
                              /usr/local/bin/zsh
     Cmnd_Alias      SU = /usr/bin/su
     Cmnd_Alias      PAGERS = /usr/bin/more, /usr/bin/pg, /usr/bin/less

     Here we override some of the compiled in default values.  We want ssuuddoo to
     log via syslog(3) using the _a_u_t_h facility in all cases.  We don't want to
     subject the full time staff to the ssuuddoo lecture, user mmiilllleerrtt need not
     give a password, and we don't want to reset the LOGNAME or USER
     environment variables when running commands as root.  Additionally, on
     the machines in the _S_E_R_V_E_R_S Host_Alias, we keep an additional local log
     file and make sure we log the year in each log line since the log entries
     will be kept around for several years.  Lastly, we disable shell escapes
     for the commands in the PAGERS Cmnd_Alias (_/_u_s_r_/_b_i_n_/_m_o_r_e, _/_u_s_r_/_b_i_n_/_p_g and
     _/_u_s_r_/_b_i_n_/_l_e_s_s).  Note that this will not effectively constrain users with
     ssuuddoo AALLLL privileges.

     # Override built-in defaults
     Defaults                syslog=auth
     Defaults>root           !set_logname
     Defaults:FULLTIMERS     !lecture
     Defaults:millert        !authenticate
     Defaults@SERVERS        log_year, logfile=/var/log/sudo.log
     Defaults!PAGERS         noexec

     The _U_s_e_r _s_p_e_c_i_f_i_c_a_t_i_o_n is the part that actually determines who may run
     what.

     root            ALL = (ALL) ALL
     %wheel          ALL = (ALL) ALL

     We let rroooott and any user in group wwhheeeell run any command on any host as
     any user.

     FULLTIMERS      ALL = NOPASSWD: ALL

     Full time sysadmins (mmiilllleerrtt, mmiikkeeff, and ddoowwddyy) may run any command on
     any host without authenticating themselves.

     PARTTIMERS      ALL = ALL

     Part time sysadmins bboossttlleeyy, jjwwffooxx, and ccrraawwll) may run any command on any
     host but they must authenticate themselves first (since the entry lacks
     the NOPASSWD tag).

     jack            CSNETS = ALL

     The user jjaacckk may run any command on the machines in the _C_S_N_E_T_S alias
     (the networks 128.138.243.0, 128.138.204.0, and 128.138.242.0).  Of those
     networks, only 128.138.204.0 has an explicit netmask (in CIDR notation)
     indicating it is a class C network.  For the other networks in _C_S_N_E_T_S,
     the local machine's netmask will be used during matching.

     lisa            CUNETS = ALL

     The user lliissaa may run any command on any host in the _C_U_N_E_T_S alias (the
     class B network 128.138.0.0).

     operator        ALL = DUMPS, KILL, SHUTDOWN, HALT, REBOOT, PRINTING,\
                     sudoedit /etc/printcap, /usr/oper/bin/

     The ooppeerraattoorr user may run commands limited to simple maintenance.  Here,
     those are commands related to backups, killing processes, the printing
     system, shutting down the system, and any commands in the directory
     _/_u_s_r_/_o_p_e_r_/_b_i_n_/.  Note that one command in the DUMPS Cmnd_Alias includes a
     sha224 digest, _/_h_o_m_e_/_o_p_e_r_a_t_o_r_/_b_i_n_/_s_t_a_r_t___b_a_c_k_u_p_s.  This is because the
     directory containing the script is writable by the operator user.  If the
     script is modified (resulting in a digest mismatch) it will no longer be
     possible to run it via ssuuddoo.

     joe             ALL = /usr/bin/su operator

     The user jjooee may only su(1) to operator.

     pete            HPPA = /usr/bin/passwd [A-Za-z]*, !/usr/bin/passwd *root*

     %opers          ALL = (: ADMINGRP) /usr/sbin/

     Users in the ooppeerrss group may run commands in _/_u_s_r_/_s_b_i_n_/ as themselves
     with any group in the _A_D_M_I_N_G_R_P Runas_Alias (the aaddmm and ooppeerr groups).

     The user ppeettee is allowed to change anyone's password except for root on
     the _H_P_P_A machines.  Because command line arguments are matched as a
     single, concatenated string, the `*' wildcard will match _m_u_l_t_i_p_l_e words.
     This example assumes that passwd(1) does not take multiple user names on
     the command line.  Note that on GNU systems, options to passwd(1) may be
     specified after the user argument.  As a result, this rule will also
     allow:

         passwd username --expire

     which may not be desirable.

     bob             SPARC = (OP) ALL : SGI = (OP) ALL

     The user bboobb may run anything on the _S_P_A_R_C and _S_G_I machines as any user
     listed in the _O_P Runas_Alias (rroooott and ooppeerraattoorr.)

     jim             +biglab = ALL

     The user jjiimm may run any command on machines in the _b_i_g_l_a_b netgroup.
     ssuuddoo knows that "biglab" is a netgroup due to the `+' prefix.

     +secretaries    ALL = PRINTING, /usr/bin/adduser, /usr/bin/rmuser

     Users in the sseeccrreettaarriieess netgroup need to help manage the printers as
     well as add and remove users, so they are allowed to run those commands
     on all machines.

     fred            ALL = (DB) NOPASSWD: ALL

     The user ffrreedd can run commands as any user in the _D_B Runas_Alias (oorraaccllee
     or ssyybbaassee) without giving a password.

     john            ALPHA = /usr/bin/su [!-]*, !/usr/bin/su *root*

     On the _A_L_P_H_A machines, user jjoohhnn may su to anyone except root but he is
     not allowed to specify any options to the su(1) command.

     jen             ALL, !SERVERS = ALL

     The user jjeenn may run any command on any machine except for those in the
     _S_E_R_V_E_R_S Host_Alias (master, mail, www and ns).

     jill            SERVERS = /usr/bin/, !SU, !SHELLS

     For any machine in the _S_E_R_V_E_R_S Host_Alias, jjiillll may run any commands in
     the directory _/_u_s_r_/_b_i_n_/ except for those commands belonging to the _S_U and
     _S_H_E_L_L_S Cmnd_Aliases.  While not specifically mentioned in the rule, the
     commands in the _P_A_G_E_R_S Cmnd_Alias all reside in _/_u_s_r_/_b_i_n and have the
     _n_o_e_x_e_c option set.

     steve           CSNETS = (operator) /usr/local/op_commands/

     The user sstteevvee may run any command in the directory
     /usr/local/op_commands/ but only as user operator.

     matt            valkyrie = KILL

     On his personal workstation, valkyrie, mmaatttt needs to be able to kill hung
     processes.

     WEBMASTERS      www = (www) ALL, (root) /usr/bin/su www

     On the host www, any user in the _W_E_B_M_A_S_T_E_R_S User_Alias (will, wendy, and
     wim), may run any command as user www (which owns the web pages) or
     simply su(1) to www.

     ALL             CDROM = NOPASSWD: /sbin/umount /CDROM,\
                     /sbin/mount -o nosuid\,nodev /dev/cd0a /CDROM

     Any user may mount or unmount a CD-ROM on the machines in the CDROM
     Host_Alias (orion, perseus, hercules) without entering a password.  This
     is a bit tedious for users to type, so it is a prime candidate for
     encapsulating in a shell script.

SSEECCUURRIITTYY NNOOTTEESS
   LLiimmiittaattiioonnss ooff tthhee ``!!'' ooppeerraattoorr
     It is generally not effective to "subtract" commands from AALLLL using the
     `!' operator.  A user can trivially circumvent this by copying the
     desired command to a different name and then executing that.  For
     example:

     bill    ALL = ALL, !SU, !SHELLS

     Doesn't really prevent bbiillll from running the commands listed in _S_U or
     _S_H_E_L_L_S since he can simply copy those commands to a different name, or
     use a shell escape from an editor or other program.  Therefore, these
     kind of restrictions should be considered advisory at best (and
     reinforced by policy).

     In general, if a user has sudo AALLLL there is nothing to prevent them from
     creating their own program that gives them a root shell (or making their
     own copy of a shell) regardless of any `!' elements in the user
     specification.

   SSeeccuurriittyy iimmpplliiccaattiioonnss ooff _f_a_s_t___g_l_o_b
     If the _f_a_s_t___g_l_o_b option is in use, it is not possible to reliably negate
     commands where the path name includes globbing (aka wildcard) characters.
     This is because the C library's fnmatch(3) function cannot resolve
     relative paths.  While this is typically only an inconvenience for rules
     that grant privileges, it can result in a security issue for rules that
     subtract or revoke privileges.

     For example, given the following _s_u_d_o_e_r_s file entry:

     john    ALL = /usr/bin/passwd [a-zA-Z0-9]*, /usr/bin/chsh [a-zA-Z0-9]*,\
                   /usr/bin/chfn [a-zA-Z0-9]*, !/usr/bin/* root

     User jjoohhnn can still run /usr/bin/passwd root if _f_a_s_t___g_l_o_b is enabled by
     changing to _/_u_s_r_/_b_i_n and running ./passwd root instead.

   PPrreevveennttiinngg sshheellll eessccaappeess
     Once ssuuddoo executes a program, that program is free to do whatever it
     pleases, including run other programs.  This can be a security issue
     since it is not uncommon for a program to allow shell escapes, which lets
     a user bypass ssuuddoo's access control and logging.  Common programs that
     permit shell escapes include shells (obviously), editors, paginators,
     mail and terminal programs.

     There are two basic approaches to this problem:

     restrict  Avoid giving users access to commands that allow the user to
               run arbitrary commands.  Many editors have a restricted mode
               where shell escapes are disabled, though ssuuddooeeddiitt is a better
               solution to running editors via ssuuddoo.  Due to the large number
               of programs that offer shell escapes, restricting users to the
               set of programs that do not is often unworkable.

     noexec    Many systems that support shared libraries have the ability to
               override default library functions by pointing an environment
               variable (usually LD_PRELOAD) to an alternate shared library.
               On such systems, ssuuddoo's _n_o_e_x_e_c functionality can be used to
               prevent a program run by ssuuddoo from executing any other
               programs.  Note, however, that this applies only to native
               dynamically-linked executables.  Statically-linked executables
               and foreign executables running under binary emulation are not
               affected.

               The _n_o_e_x_e_c feature is known to work on SunOS, Solaris, *BSD,
               Linux, IRIX, Tru64 UNIX, macOS, HP-UX 11.x and AIX 5.3 and
               above.  It should be supported on most operating systems that
               support the LD_PRELOAD environment variable.  Check your
               operating system's manual pages for the dynamic linker (usually
               ld.so, ld.so.1, dyld, dld.sl, rld, or loader) to see if
               LD_PRELOAD is supported.

               On Solaris 10 and higher, _n_o_e_x_e_c uses Solaris privileges
               instead of the LD_PRELOAD environment variable.

               To enable _n_o_e_x_e_c for a command, use the NOEXEC tag as
               documented in the User Specification section above.  Here is
               that example again:

               aaron   shanty = NOEXEC: /usr/bin/more, /usr/bin/vi

               This allows user aaaarroonn to run _/_u_s_r_/_b_i_n_/_m_o_r_e and _/_u_s_r_/_b_i_n_/_v_i
               with _n_o_e_x_e_c enabled.  This will prevent those two commands from
               executing other commands (such as a shell).  If you are unsure
               whether or not your system is capable of supporting _n_o_e_x_e_c you
               can always just try it out and check whether shell escapes work
               when _n_o_e_x_e_c is enabled.

     Note that restricting shell escapes is not a panacea.  Programs running
     as root are still capable of many potentially hazardous operations (such
     as changing or overwriting files) that could lead to unintended privilege
     escalation.  In the specific case of an editor, a safer approach is to
     give the user permission to run ssuuddooeeddiitt (see below).

   SSeeccuurree eeddiittiinngg
     The ssuuddooeerrss plugin includes ssuuddooeeddiitt support which allows users to
     securely edit files with the editor of their choice.  As ssuuddooeeddiitt is a
     built-in command, it must be specified in the _s_u_d_o_e_r_s file without a
     leading path.  However, it may take command line arguments just as a
     normal command does.  Wildcards used in _s_u_d_o_e_d_i_t command line arguments
     are expected to be path names, so a forward slash (`/') will not be
     matched by a wildcard.

     Unlike other ssuuddoo commands, the editor is run with the permissions of the
     invoking user and with the environment unmodified.  More information may
     be found in the description of the --ee option in sudo(1m).

     For example, to allow user operator to edit the "message of the day"
     file:

           operator        sudoedit /etc/motd

     The operator user then runs ssuuddooeeddiitt as follows:

           $ sudoedit /etc/motd

     The editor will run as the operator user, not root, on a temporary copy
     of _/_e_t_c_/_m_o_t_d.  After the file has been edited, _/_e_t_c_/_m_o_t_d will be updated
     with the contents of the temporary copy.

     Users should _n_e_v_e_r be granted ssuuddooeeddiitt permission to edit a file that
     resides in a directory the user has write access to, either directly or
     via a wildcard.  If the user has write access to the directory it is
     possible to replace the legitimate file with a link to another file,
     allowing the editing of arbitrary files.  To prevent this, starting with
     version 1.8.16, symbolic links will not be followed in writable
     directories and ssuuddooeeddiitt will refuse to edit a file located in a writable
     directory unless the _s_u_d_o_e_d_i_t___c_h_e_c_k_d_i_r option has been disabled or the
     invoking user is root.  Additionally, in version 1.8.15 and higher,
     ssuuddooeeddiitt will refuse to open a symbolic link unless either the
     _s_u_d_o_e_d_i_t___f_o_l_l_o_w option is enabled or the _s_u_d_o_e_d_i_t command is prefixed
     with the FOLLOW tag in the _s_u_d_o_e_r_s file.

   TTiimmee ssttaammpp ffiillee cchheecckkss
     ssuuddooeerrss will check the ownership of its time stamp directory
     (_/_v_a_r_/_r_u_n_/_s_u_d_o_/_t_s by default) and ignore the directory's contents if it
     is not owned by root or if it is writable by a user other than root.
     Older versions of ssuuddoo stored time stamp files in _/_t_m_p; this is no longer
     recommended as it may be possible for a user to create the time stamp
     themselves on systems that allow unprivileged users to change the
     ownership of files they create.

     While the time stamp directory _s_h_o_u_l_d be cleared at reboot time, not all
     systems contain a _/_r_u_n or _/_v_a_r_/_r_u_n directory.  To avoid potential
     problems, ssuuddooeerrss will ignore time stamp files that date from before the
     machine booted on systems where the boot time is available.

     Some systems with graphical desktop environments allow unprivileged users
     to change the system clock.  Since ssuuddooeerrss relies on the system clock for
     time stamp validation, it may be possible on such systems for a user to
     run ssuuddoo for longer than _t_i_m_e_s_t_a_m_p___t_i_m_e_o_u_t by setting the clock back.  To
     combat this, ssuuddooeerrss uses a monotonic clock (which never moves backwards)
     for its time stamps if the system supports it.

     ssuuddooeerrss will not honor time stamps set far in the future.  Time stamps
     with a date greater than current_time + 2 * TIMEOUT will be ignored and
     ssuuddooeerrss will log and complain.

     If the _t_i_m_e_s_t_a_m_p___t_y_p_e option is set to "tty", the time stamp record
     includes the device number of the terminal the user authenticated with.
     This provides per-terminal granularity but time stamp records may still
     outlive the user's session.

     Unless the _t_i_m_e_s_t_a_m_p___t_y_p_e option is set to "global", the time stamp
     record also includes the session ID of the process that last
     authenticated.  This prevents processes in different terminal sessions
     from using the same time stamp record.  On systems where a process's
     start time can be queried, the start time of the session leader is
     recorded in the time stamp record.  If no terminal is present or the
     _t_i_m_e_s_t_a_m_p___t_y_p_e option is set to "ppid", the start time of the parent
     process is used instead.  In most cases this will prevent a time stamp
     record from being re-used without the user entering a password when
     logging out and back in again.

DDEEBBUUGGGGIINNGG
     Versions 1.8.4 and higher of the ssuuddooeerrss plugin support a flexible
     debugging framework that can help track down what the plugin is doing
     internally if there is a problem.  This can be configured in the
     sudo.conf(4) file.

     The ssuuddooeerrss plugin uses the same debug flag format as the ssuuddoo front-end:
     _s_u_b_s_y_s_t_e_m@_p_r_i_o_r_i_t_y.

     The priorities used by ssuuddooeerrss, in order of decreasing severity, are:
     _c_r_i_t, _e_r_r, _w_a_r_n, _n_o_t_i_c_e, _d_i_a_g, _i_n_f_o, _t_r_a_c_e and _d_e_b_u_g.  Each priority,
     when specified, also includes all priorities higher than it.  For
     example, a priority of _n_o_t_i_c_e would include debug messages logged at
     _n_o_t_i_c_e and higher.

     The following subsystems are used by the ssuuddooeerrss plugin:

     _a_l_i_a_s     User_Alias, Runas_Alias, Host_Alias and Cmnd_Alias processing

     _a_l_l       matches every subsystem

     _a_u_d_i_t     BSM and Linux audit code

     _a_u_t_h      user authentication

     _d_e_f_a_u_l_t_s  _s_u_d_o_e_r_s file _D_e_f_a_u_l_t_s settings

     _e_n_v       environment handling

     _l_d_a_p      LDAP-based sudoers

     _l_o_g_g_i_n_g   logging support

     _m_a_t_c_h     matching of users, groups, hosts and netgroups in the _s_u_d_o_e_r_s
               file

     _n_e_t_i_f     network interface handling

     _n_s_s       network service switch handling in ssuuddooeerrss

     _p_a_r_s_e_r    _s_u_d_o_e_r_s file parsing

     _p_e_r_m_s     permission setting

     _p_l_u_g_i_n    The equivalent of _m_a_i_n for the plugin.

     _p_t_y       pseudo-tty related code

     _r_b_t_r_e_e    redblack tree internals

     _s_s_s_d      SSSD-based sudoers

     _u_t_i_l      utility functions
     For example:

     Debug sudo /var/log/sudo_debug match@info,nss@info

     For more information, see the sudo.conf(4) manual.

SSEEEE AALLSSOO
     ssh(1), su(1), fnmatch(3), glob(3), mktemp(3), strftime(3), sudo.conf(4),
     sudo_plugin(4), sudoers.ldap(4), sudoers_timestamp(4), sudo(1m), visudo(1m)

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

           Todd C. Miller

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

CCAAVVEEAATTSS
     The _s_u_d_o_e_r_s file should aallwwaayyss be edited by the vviissuuddoo command which
     locks the file and does grammatical checking.  It is imperative that the
     _s_u_d_o_e_r_s file be free of syntax errors since ssuuddoo will not run with a
     syntactically incorrect _s_u_d_o_e_r_s file.

     When using netgroups of machines (as opposed to users), if you store
     fully qualified host name in the netgroup (as is usually the case), you
     either need to have the machine's host name be fully qualified as
     returned by the hostname command or use the _f_q_d_n option in _s_u_d_o_e_r_s.

BBUUGGSS
     If you feel you have found a bug in ssuuddoo, please submit a bug report at
     https://bugzilla.sudo.ws/

SSUUPPPPOORRTT
     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.

DDIISSCCLLAAIIMMEERR
     ssuuddoo 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
     file distributed with ssuuddoo or https://www.sudo.ws/license.html for
     complete details.

Sudo 1.8.26                    December 20, 2018                   Sudo 1.8.26
