If we wanted to provide tighter control over how passwords are created and reused, such as a
mixture of upper- and lowercase characters in every password, we need to enable the PASSWORD_
VERIFY_FUNCTION limit in each applicable profile. Oracle provides a template for enforcing an
FIGURE 9-4 Changing password limits with Oracle Enterprise Manager
296 Oracle Database 11g DBA Handbook
organization??™s password policy. It??™s located in $ORACLE_HOME/rdbms/admin/utlpwdmg.sql.
Some key sections of this script follow:
CREATE OR REPLACE FUNCTION verify_function_11G
(username varchar2,
password varchar2,
old_password varchar2)
RETURN boolean IS
n boolean;
m integer;
differ integer;
isdigit boolean;
ischar boolean;
ispunct boolean;
db_name varchar2(40);
digitarray varchar2(20);
punctarray varchar2(25);
chararray varchar2(52);
i_char varchar2(10);
simple_password varchar2(10);
reverse_user varchar2(32);
BEGIN
digitarray:= '0123456789';
chararray:= 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
. . .
-- Check if the password is same as the username reversed
FOR i in REVERSE 1..length(username) LOOP
reverse_user := reverse_user || substr(username, i, 1);
END LOOP;
IF NLS_LOWER(password) = NLS_LOWER(reverse_user) THEN
raise_application_error(-20003, 'Password same as username reversed');
END IF;
. . .
-- Everything is fine; return TRUE ;
RETURN(TRUE);
END;
/
-- This script alters the default parameters for Password Management
-- This means that all the users on the system have Password Management
-- enabled and set to the following values unless another profile is
-- created with parameter values set to different value or UNLIMITED
-- is created and assigned to the user.
Pages:
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498