PAM_PWHISTORY
Section: Linux\-PAM Manual (8)
Updated: 11/25/2020
Page Index
NAME
pam_pwhistory - PAM module to remember last passwords
SYNOPSIS
-
pam_pwhistory.so [debug] [use_authtok] [enforce_for_root] [remember=N] [retry=N] [authtok_type=STRING]
DESCRIPTION
This module saves the last passwords for each user in order to force password change history and keep the user from alternating between the same password too frequently.
This module does not work together with kerberos. In general, it does not make much sense to use this module in conjunction with NIS or LDAP, since the old passwords are stored on the local machine and are not available on another machine for password history checking.
OPTIONS
debug
-
Turns on debugging via
syslog(3).
use_authtok
-
When password changing enforce the module to use the new password provided by a previously stacked
password
module (this is used in the example of the stacking of the
pam_passwdqc
module documented below).
enforce_for_root
-
If this option is set, the check is enforced for root, too.
remember=N
-
The last
N
passwords for each user are saved in
/etc/security/opasswd. The default is
10. Value of
0
makes the module to keep the existing contents of the
opasswd
file unchanged.
retry=N
-
Prompt user at most
N
times before returning with error. The default is
1.
authtok_type=STRING
-
See
pam_get_authtok(3)
for more details.
MODULE TYPES PROVIDED
Only the
password
module type is provided.
RETURN VALUES
PAM_AUTHTOK_ERR
-
No new password was entered, the user aborted password change or new password couldn't be set.
PAM_IGNORE
-
Password history was disabled.
PAM_MAXTRIES
-
Password was rejected too often.
PAM_USER_UNKNOWN
-
User is not known to system.
EXAMPLES
An example password section would be:
-
#%PAM-1.0
password required pam_pwhistory.so
password required pam_unix.so use_authtok
In combination with
pam_passwdqc:
-
#%PAM-1.0
password required pam_passwdqc.so config=/etc/passwdqc.conf
password required pam_pwhistory.so use_authtok
password required pam_unix.so use_authtok
FILES
/etc/security/opasswd
-
File with password history
SEE ALSO
pam.conf(5),
pam.d(5),
pam(8)
pam_get_authtok(3)
AUTHOR
pam_pwhistory was written by Thorsten Kukuk <kukuk@thkukuk.de>