The /etc/login.defs
is the file set the shadow password parameters, its contain the users account settings on the os its contain the min and max days for accounts access , contain the encryption method contain the umask settings you can check this man page for more information
http://man7.org/linux/man-pages/man5/login.defs.5.html
If you would like to change the days and the warn days
Set the PASS_MAX_DAYS parameter to 90
# sudo chage --maxdays 90 <user>
Set the PASS_MIN_DAYS parameter
# sudo chage --mindays 7 <user>
Set the PASS_WARN_AGE parameter
# sudo chage --warndays 7 <user>
Change <user> the user account you want to conigure
I consile to give umask 077 to /etc/login.defs