Script to enforce password authentication policy

[Alex_hunt]

Dear All

I want a script for enforcing password authentication on linux
systems.

Password Requirements:

Min password lenghth =6

Max password lenghth =8

PASS_MAX_DAYS 45

PASS_MIN_DAYS 7

PASS_WARN_AGE 10

Account should be lockout for 5 min after 5 unsuccessful attempt

Password must contain an uppercase letter and a digit.

Script should be such that authentication should apply on all users on
the system as there are multiple users using the same machine.

I had found something relevant to this,please have a look

usr/bin/chage -m 7 -M 45 -W 10 username

echo password requisite /lib/security/pam_cracklib.so retry=3 minlen=6
lcredit=1 ucredit=1 dcredit=1 ocredit=0 >> /etc/pam.d/system-auth #to
enforce password complexity

#Password History

touch /etc/security/opasswd

chown root:root /etc/security/opasswd

chmod 600 /etc/security/opasswd

#to stop using last 15 password

echo password sufficient /lib/security/pam_unix.so nullok use_authtok
md5 shadow remember=15 >> /etc/pam.d/system-auth

#Account Lockout

touch /var/log/faillog

chown root:root /var/log/faillog

chmod 600 /var/log/faillog

echo auth required /lib/security/pam_tally.so onerr=fail deny=5
unlock_time=300 >> /etc/pam.d/system-auth

echo account required /lib/security/pam_tally.so >> /etc/
pam.d/system-auth

problem is that how to fetch all users whose uid is greater than 500
and put it in chage command