PAM_AUTHTOK_CHECK(5) Standards, Environments, and Macros PAM_AUTHTOK_CHECK(5)


NAME


pam_authtok_check - authentication and password management module

SYNOPSIS


pam_authtok_check.so.1


DESCRIPTION


pam_authtok_check provides functionality to the Password Management
stack. The implementation of pam_sm_chauthtok() performs a number of
checks on the construction of the newly entered password.
pam_sm_chauthtok() is invoked twice by the PAM framework, once with flags
set to PAM_PRELIM_CHECK, and once with flags set to PAM_UPDATE_AUTHTOK.
This module only performs its checks during the first invocation. This
module expects the current authentication token in the PAM_OLDAUTHTOK
item, the new (to be checked) password in the PAM_AUTHTOK item, and the
login name in the PAM_USER item. The checks performed by this module are:

length
The password length should not be less that the
minimum specified in /etc/default/passwd.


circular shift
The password should not be a circular shift of the
login name. This check may be disabled in
/etc/default/passwd.


complexity
The password should contain at least the minimum
number of characters described by the parameters
MINALPHA, MINNONALPHA, MINDIGIT, and MINSPECIAL. Note
that MINNONALPHA describes the same character classes
as MINDIGIT and MINSPECIAL combined; therefore the
user cannot specify both MINNONALPHA and MINSPECIAL
(or MINDIGIT). The user must choose which of the two
options to use. Furthermore, the WHITESPACE parameter
determines whether whitespace characters are allowed.
If unspecified MINALPHA is 2, MINNONALPHA is 1 and
WHITESPACE is yes


variation
The old and new passwords must differ by at least the
MINDIFF value specified in /etc/default/passwd. If
unspecified, the default is 3. For accounts in name
services which support password history checking, if
prior history is defined, the new password must not
match the prior passwords.


dictionary check
The password must not be based on a dictionary word.
The list of words to be used for the site's
dictionary can be specified with DICTIONLIST. It
should contain a comma-separated list of filenames,
one word per line. The database that is created from
these files is stored in the directory named by
DICTIONDBDIR (defaults to /var/passwd). See
mkpwdict(1M) for information on pre-generating the
database. If neither DICTIONLIST nor DICTIONDBDIR is
specified, no dictionary check is made.


upper/lower case
The password must contain at least the minimum of
upper- and lower-case letters specified by the
MINUPPER and MINLOWER values in /etc/default/passwd.
If unspecified, the defaults are 0.


maximum repeats
The password must not contain more consecutively
repeating characters than specified by the MAXREPEATS
value in /etc/default/passwd. If unspecified, no
repeat character check is made.


The following option may be passed to the module:

force_check
If the PAM_NO_AUTHTOK_CHECK flag set, force_check ignores
this flag. The PAM_NO_AUTHTOK_CHECK flag can be set to
bypass password checks (see pam_chauthtok(3PAM)).


debug
syslog(3C) debugging information at the LOG_DEBUG level


RETURN VALUES


If the password in PAM_AUTHTOK passes all tests, PAM_SUCCESS is returned.
If any of the tests fail, PAM_AUTHTOK_ERR is returned.

FILES


/etc/default/passwd
See passwd(1) for a description of the contents.


ATTRIBUTES


See attributes(5) for descriptions of the following attributes:


+--------------------+-------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------------+
|Interface Stability | Evolving |
+--------------------+-------------------------+
|MT Level | MT-Safe with exceptions |
+--------------------+-------------------------+

SEE ALSO


passwd(1), pam(3PAM), mkpwdict(1M), pam_chauthtok(3PAM), syslog(3C),
libpam(3LIB), pam.conf(4), passwd(4), shadow(4), attributes(5),
pam_authtok_get(5), pam_authtok_store(5), pam_dhkeys(5),
pam_passwd_auth(5), pam_unix_account(5), pam_unix_auth(5),
pam_unix_session(5)

NOTES


The interfaces in libpam(3LIB) are MT-Safe only if each thread within the
multi-threaded application uses its own PAM handle.


The pam_unix(5) module is no longer supported. Similar functionality is
provided by pam_authtok_check(5), pam_authtok_get(5),
pam_authtok_store(5), pam_dhkeys(5), pam_passwd_auth(5),
pam_unix_account(5), pam_unix_auth(5), and pam_unix_session(5).


March 1, 2005 PAM_AUTHTOK_CHECK(5)