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|
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
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