solution to make static changes in pg_hba.conf file?

hi,

i assigned super user privelledge to a user by specifing entries in pg_hba.conf file as

host all newuser 127.1.1.1 md5

and the default postgres user is made access to only the default postgres databse and is no more the super user.

the problem is that this conf file is available to all and can be changed again.

can someone assist me with a solution to make this changes static.
thanks
happy new year:-)
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