U may:

for insert/update password
use some trigger:

create or replace trigger BERNIES.BI_IMAGE_SHOW_RULES
before insert or update on BERNIES.IMAGE_SHOW_RULES
for each row
begin :new.pwd_fileld := my_enscript(:new.pwd_fileld);
end;
/

for read (select) rows from this tables use view:
1. write some store function for descript field

2. use view for read rows from real table:

create or replace view v_descript_pwd
( ...
pwd,
...
)
as select
...
descript(pwd_field),
..
from user_list;