Man page 8 : pam_succeed_if

pam_succeed_if - test account characteristics

pam_succeed_if.so [flag...] [condition...]

pam_succeed_if.so is designed to succeed or fail authentication based on characteristics of the account belonging to the user being authenticated. One use is to select whether to load other modules based on this test.

The module should be given one or more conditions as module arguments, and authentication will succeed only if all of the conditions are met.

The following flags are supported:

debug
    Turns on debugging messages sent to syslog.

use_uid
    Evaluate conditions using the account of the user whose UID the application is running under instead of the user being authenticated.

quiet
    Don\'t log failure or success to the system log.

quiet_fail
    Don\'t log failure to the system log.

quiet_success
    Don\'t log success to the system log.

Conditions are three words: a field, a test, and a value to test for.

Available fields are user, uid, gid, shell, home and service:

field < number
    Field has a value numerically less than number.

field <= number
    Field has a value numerically less than or equal to number.

field eq number
    Field has a value numerically equal to number.

field >= number
    Field has a value numerically greater than or equal to number.

field > number
    Field has a value numerically greater than number.

field ne number
    Field has a value numerically different from number.

field = string
    Field exactly matches the given string.

field != string
    Field does not match the given string.

field =~ glob
    Field matches the given glob.

field !~ glob
    Field does not match the given glob.

field in item:item:...
    Field is contained in the list of items separated by colons.

field notin item:item:...
    Field is not contained in the list of items separated by colons.

user ingroup group
    User is in given group.

user notingroup group
    User is not in given group.

user innetgr netgroup
    (user,host) is in given netgroup.

user notinnetgr group
    (user,host) is not in given netgroup.

All module types (account, auth, password and session) are provided.

PAM_SUCCESS
    The condition was true.

PAM_AUTH_ERR
    The condition was false.

PAM_SERVICE_ERR
    A service error occurred or the arguments can\'t be parsed correctly.

To emulate the behaviour of pam_wheel, except there is no fallback to group 0:


    .

auth required pam_succeed_if.so quiet user ingroup wheel

.

Given that the type matches, only loads the othermodule rule if the UID is over 500. Adjust the number after default to skip several rules.


    .

type [default=1 success=ignore] pam_succeed_if.so quiet uid > 500
type required othermodule.so arguments...

.

glob(7), pam(7)

Nalin Dahyabhai <>