Ubuntu 14.04
Sponsored Link

Set Password Rules
2016/01/20
 
Set Password Rules for security reasons.
[1] Install password quality checking library.
root@dlp:~#
apt-get -y install libpam-pwquality
[2] Set number of days for password Expiration.
Users must change their password within the days.
This setting impacts only when creating a user, not impacts to exisiting users.
If set to exisiting users, run the command "chage -M (days) (user)".
root@dlp:~#
vi /etc/login.defs
# line 160: set 60 for Password Expiration

PASS_MAX_DAYS
60
[3] Set minimum number of days available of password.
Users must use their password at least this days after changing it.
This setting impacts only when creating a user, not impacts to exisiting users.
If set to exisiting users, run the command "chage -m (days) (user)".
root@dlp:~#
vi /etc/login.defs
# line 161: set 2 for Minimum number of days available

PASS_MIN_DAYS
2
[4] Set number of days for warnings before expiration.
This setting impacts only when creating a user, not impacts to exisiting users.
If set to exisiting users, run the command "chage -W (days) (user)".
root@dlp:~#
vi /etc/login.defs
# line 162: set 7 for number of days for warnings

PASS_WARN_AGE
7
[5] Limit using a password that was used in past.
Users can not set the same password within the generation.
root@dlp:~#
vi /etc/pam.d/common-password
# line 26: prohibit to use the same password for 5 generation in past

password        [success=1 default=ignore]      pam_unix.so obscure use_authtok \
                                                try_first_pass sha512 remember=5
[6] Set minimum password length.
Users can not set thier password length less than this parameter.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set 8 for minimum password length

password        requisite                       pam_pwquality.so retry=3 minlen=8
[7] Set minimum number of required classes of characters for the new password. (kinds ⇒ UpperCase / LowerCase / Digits / Others)
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set 2 for minimum number of required classes of characters

password        requisite                       pam_pwquality.so retry=3 minclass=2
[8] Set maximum number of allowed consecutive same characters in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set 2 for maximum number of allowed consecutive same characters

password        requisite                       pam_pwquality.so retry=3 maxrepeat=2
[9] Set maximum number of allowed consecutive characters of the same class in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set 4 for maximum number of allowed consecutive characters of the same class

password        requisite                       pam_pwquality.so retry=3 maxclassrepeat=4
[10] Require at least one lowercase character in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 lcredit=-1
[11] Require at least one uppercase character in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 ucredit=-1
[12] Require at least one digit in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 dcredit=-1
[13] Require at least one other character in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 ocredit=-1
[14] Set maximum length of monotonic character sequences in the new password. (ex ⇒ '12345', 'fedcb')
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 maxsequence=3
[15] Set number of characters in the new password that must not be present in the old password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 difok=5
[16] Check whether the words longer than 3 characters from the GECOS field of the user's passwd entry are contained in the new password.
root@dlp:~#
vi /etc/pam.d/common-password
# line 25: set like follows

password        requisite                       pam_pwquality.so retry=3 gecoscheck=1
[17] Set hash/crypt algorithm for new passwords. (default is sha512)
root@dlp:~#
vi /etc/pam.d/common-password
# line 26: set to sha512 (for others, md5 or bigcrypt and so on)

password        [success=1 default=ignore]      pam_unix.so obscure use_authtok \
                                                try_first_pass sha512
Matched Content
 
Tweet