How to create Oracle password verify function.

1. create password_verify function by sys

CREATE OR REPLACE FUNCTION toa_pass_verify (
   username       VARCHAR2,
   PASSWORD       VARCHAR2,
   old_password   VARCHAR2
)
   RETURN BOOLEAN
IS
   n                BOOLEAN;
   m                INTEGER;
   differ           INTEGER;
   isdigit          BOOLEAN;
   ischarlower      BOOLEAN;
   ischarupper      BOOLEAN;
   ispunct          BOOLEAN;
   digitarray       VARCHAR2 (20);
   punctarray       VARCHAR2 (25);
   chararraylower   VARCHAR2 (52);
   chararrayupper   VARCHAR2 (52);
BEGIN
   digitarray := '0123456789';
   chararraylower := 'abcdefghijklmnopqrstuvwxyz';
   chararrayupper := 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
   punctarray := '!"#$%&()``*+,-/:;<=>?_{}[]';
-- Check if the password is same as the username
   IF NLS_LOWER (PASSWORD) = NLS_LOWER (username)
   THEN
      raise_application_error (-20001, 'Password same as or similar to user');
   END IF;
-- Check for the minimum length of the password
   IF LENGTH (PASSWORD) < 8
   THEN
      raise_application_error (-20002, 'Password length less than 8');
   END IF;
-- Check if the password is too simple. A dictionary of words may be
-- maintained and a check may be made so as not to allow the words
-- that are too simple for the password.
   IF NLS_LOWER (PASSWORD) IN
         ('welcome', 'database', 'account', 'user', 'password', 'oracle',
          'computer', 'abcd')
   THEN
      raise_application_error (-20002, 'Password too simple');
   END IF;
-- Check if the password contains at least one letter, one digit and one
-- punctuation mark.
-- 1. Check for the digit
   isdigit := FALSE;
   m := LENGTH (PASSWORD);
   FOR i IN 1 .. 10
   LOOP
      FOR j IN 1 .. m
      LOOP
         IF SUBSTR (PASSWORD, j, 1) = SUBSTR (digitarray, i, 1)
         THEN
            isdigit := TRUE;
            --GOTO findcharlower;
         END IF;
      END LOOP;
   END LOOP;
   IF isdigit = FALSE
   THEN
      raise_application_error
         (-20003,
          'Password should contain at least one digit'
         );
   END IF;
-- 2. Check for the lowwer case character
   ischarlower := FALSE;
   FOR i IN 1 .. LENGTH (chararraylower)
   LOOP
      FOR j IN 1 .. m
      LOOP
         IF SUBSTR (PASSWORD, j, 1) = SUBSTR (chararraylower, i, 1)
         THEN
            ischarlower := TRUE;
            --GOTO findcharupper;
         END IF;
      END LOOP;
   END LOOP;
   IF ischarlower = FALSE
   THEN
      raise_application_error
         (-20003,
          'Password should contain at least one lower case character and one punctuation'
         );
   END IF;
-- 3. Check for the upper case character
   ischarupper := FALSE;
   FOR i IN 1 .. LENGTH (chararrayupper)
   LOOP
      FOR j IN 1 .. m
      LOOP
         IF SUBSTR (PASSWORD, j, 1) = SUBSTR (chararrayupper, i, 1)
         THEN
            ischarupper := TRUE;
            --GOTO findpunct;
         END IF;
      END LOOP;
   END LOOP;
   IF ischarupper = FALSE
   THEN
      raise_application_error
         (-20003,
          'Password should contain at least one upper character and one punctuation'
         );
   END IF;
-- 4. Check for the punctuation
   ispunct := FALSE;
   FOR i IN 1 .. LENGTH (punctarray)
   LOOP
      FOR j IN 1 .. m
      LOOP
         IF SUBSTR (PASSWORD, j, 1) = SUBSTR (punctarray, i, 1)
         THEN
            ispunct := TRUE;
            --GOTO endsearch;
         END IF;
      END LOOP;
   END LOOP;
   IF ispunct = FALSE
   THEN
      raise_application_error
         (-20003,
          'Password should contain at least one digit, one character and one punctuation'
         );
   END IF;
-- Everything is fine; return TRUE ;
   RETURN (TRUE);
END;
/

2. create profile:

CREATE PROFILE MY_PROFILE LIMIT
  FAILED_LOGIN_ATTEMPTS 3  -- Account locked after 3 failed logins.
  PASSWORD_LOCK_TIME unlimited     -- Number of days account is locked for. UNLIMITED required explicit unlock by DBA.
  PASSWORD_LIFE_TIME 60    -- Password expires after 90 days.
  PASSWORD_GRACE_TIME 6    -- Grace period for password expiration.
  PASSWORD_REUSE_TIME 360  -- Number of days until a specific password can be reused. UNLIMITED means never.
  PASSWORD_REUSE_MAX 6    -- The number of changes required before a password can be reused. UNLIMITED means never.
  PASSWORD_VERIFY_FUNCTION PASSWORD_VERIFY
  3. create users:

create user          TEST
identified by        password4TEST#
profile              MY_PROFILE