The wrap utility (an external program installed with the Oracle software) has been around for years and uses a proprietary algorithm to 'scramble' the source code so as to make it essentially unreadable by the human eye. To illustrate what the wrap utility can accomplish let's look at a pair of files declaring a package specification and a package body. First, the package specification:
CREATE PACKAGE dates_pkg
AS
FUNCTION julian_date
( date_to_convert DATE )
RETURN NUMBER;
FUNCTION minutes_since_midnight
( timevalue DATE )
RETURN NUMBER;
FUNCTION minutes_elapsed
( lowdate DATE
, highdate DATE )
RETURN NUMBER;
END dates_pkg;
/
Nothing here the everyday user can't see, so we'll leave this one unscrambled. Now let's look at the package body:
CREATE PACKAGE BODY dates_pkg
AS
FUNCTION julian_date
( date_to_convert DATE)
RETURN NUMBER
IS
varch_value VARCHAR (10);
num_value NUMBER (20);
BEGIN
--
-- First, we take a date and convert it to a date by converting it
-- to a character string using the same format we will use to
-- convert it BACK to a date again
--
-- Oh, then we convert it back to a character string
--
-- In Julian format, which is a number
--
SELECT TO_CHAR
( TO_DATE(TO_CHAR(date_to_convert,'MM/DD/YYYY'),'MM/DD/YYYY')
, 'J')
INTO varch_value
FROM dual;
--
-- Okay, so we had a Julian date as a number but we changed it to
-- a character string so we could go back and make it a ...
-- NUMBER ... again
--
SELECT TO_NUMBER (varch_value)
INTO num_value
FROM dual;
--
-- So, we finally make up our mind and keep it a number and
-- return it from the function
--
RETURN (num_value);
END julian_date;
FUNCTION minutes_since_midnight (
timevalue DATE)
RETURN NUMBER
IS
secs_elapsed NUMBER (20);
mins_elapsed NUMBER (20);
BEGIN
--
-- So now we take a date and extract the time portion of it,
-- convert that BACK to a date, then convert THAT to a string
-- of seconds and convert THAT to a number
--
-- Is it me, or are we essentially driving across town just to
-- go next door?
--
SELECT TO_NUMBER
( TO_CHAR(TO_DATE(TO_CHAR(timevalue,'HH:MI AM'),'HH:MI AM')
, 'SSSSS') )
INTO secs_elapsed
FROM dual;
--
-- Oooo, now we divide that total number of seconds by ...
-- wait for it ...
-- any second now ...
-- 60! Who would have thought that 60 seconds equals
-- one minute?
--
SELECT (secs_elapsed / 60)
INTO mins_elapsed
FROM dual;
--
-- Before we rest on our laurels we return the minutes since midnight
--
RETURN (mins_elapsed);
END minutes_since_midnight;
FUNCTION minutes_elapsed
( lowdate DATE
, highdate DATE )
RETURN NUMBER
IS
final_number NUMBER (20);
low_julian NUMBER (20);
high_julian NUMBER (20);
num_days NUMBER (20);
num_minutes NUMBER (20);
temp_mins NUMBER (20);
min_low NUMBER (20);
min_high NUMBER (20);
BEGIN
--
-- Now, why didn't we use this julian_date function in the
-- last installment of Julian conversions?
--
-- Oh, yeah, because we just WROTE that wonderful function
--
-- So, okay, we take our date values and return the Julian
-- representations of them using all of the mathematical
-- aerobics from earlier
--
-- I guess this is so much easier than simply subtracting
-- them
--
SELECT julian_date (lowdate)
INTO low_julian
FROM dual;
SELECT julian_date (highdate)
INTO high_julian
FROM dual;
--
-- Woo-hoo! Higher math time! Subtract the Julian dates
-- and get the number of days
--
-- Isn't that what we'd get if we just subtracted the
-- submitted dates as-is?
--
-- Of course it is
--
SELECT (high_julian - low_julian)
INTO num_days
FROM dual;
--
-- Now we calculate the total minutes elapsed
-- using our values generated by our extreme
-- gyrations
--
-- I'm out of breath just thinking about all of this work
--
SELECT (num_days * 1440)
INTO num_minutes
FROM dual;
--
-- And now we put those other mathematical moves
-- to use
--
-- Tell me again why we think we're smarter than
-- the average bear?
--
SELECT minutes_since_midnight (lowdate)
INTO min_low
FROM dual;
SELECT minutes_since_midnight (highdate)
INTO min_high
FROM dual;
--
-- Now this is disgusting
--
-- Using a TEMP variable to aid in simple mathematical
-- processing
--
SELECT (min_high - min_low)
INTO temp_mins
FROM dual;
--
-- And this is better than:
-- select (end_date - start_date)*1440 because?
--
SELECT (num_minutes + temp_mins)
INTO final_number
FROM dual;
RETURN (final_number);
END minutes_elapsed;
END dates_pkg;
/
There are some areas here which would be good to obscure (such as the actual program logic and my dripping sarcasm). Let's run this through wrap and see what results:
wrap iname=datepkg.pls
PL/SQL Wrapper: Release 10.2.0.3.0- Production on Mon Jun 02 12:04:26 2008
Copyright (c) 1993, 2004, Oracle. All rights reserved.
Processing datepkg.pls to datepkg.plb
(Note that wrap requires only an input file name; it will supply the output file name from the input file and change the extension to plb. You can, of course, supply an output file name using the oname parameter:
wrap iname=myfile.sql oname=yourfile.plq
and the wrap utility will be perfectly happy. I prefer to accept the default behaviour.)So now we look at the contents of datepkg.plb and see what wrap hath wrought:
CREATE PACKAGE BODY dates_pkg wrapped
a000000
b2
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
abcd
b
8fd 2ea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/
It doesn't look the same as the source code, does it. The wrap utility was provided to do just that, obscure PL/SQL code/logic so the end user can't see it. Installing either of the package bodies (datepkg.pls or datepkg.plb) results in the same functional code in the database, it's just that the datepkg.plb script can't be decoded by anyone except Oracle (and, in any of the SOURCE views [DBA_SOURCE, USER_SOURCE] all that is revealed is the wrapped text). That, of course, means THERE IS NO ORACLE-SUPPLIED OR ORACLE SUPPORTED UNWRAP UTILITY; you'll need to save your original source code in the event you need to modify it due to bug fixes (heaven forbid) and/or functionality changes since you won't get it back from the wrapped file.How do you execute a .plb file? Pretty much like you'd run any other .sql script:
SQL> @datepkg
SQL> CREATE OR REPLACE PACKAGE dates_pkg
2 AS
3 FUNCTION julian_date
4 ( date_to_convert DATE )
5 RETURN NUMBER;
6
7 FUNCTION minutes_since_midnight
8 ( timevalue DATE )
9 RETURN NUMBER;
10
11 FUNCTION minutes_elapsed
12 ( lowdate DATE
13 , highdate DATE )
14 RETURN NUMBER;
15
16 END dates_pkg;
17 /
Package created.
SQL>
SQL> @datepkg.plb
SQL> CREATE or replace PACKAGE BODY dates_pkg wrapped
2 a000000
3 b2
4 abcd
5 abcd
6 abcd
7 abcd
8 abcd
9 abcd
10 abcd
11 abcd
12 abcd
13 abcd
14 abcd
15 abcd
16 abcd
17 abcd
18 abcd
19 b
20 8fd 2ea
21 HqtWzGgdR01NBtyeAlYcu2V4y4Awg5DDLtAFyi/NDfmUx4K5yY1+DfxrrfMT24qrdohuXNxN
22 CQocIyZ3+aqU08q0OcZMwOM4QHgsu3+AcbwGHTdMupDu+MSdJPlNmp0/yVSRDrG8wWMaYgec
23 vGt1Cp4MwH91At1+jX5cMZu2KV0BDzASgJGaUo8ABfe5wPICeEG46jz8RhNBcZ1SW33eXn7t
24 B7wXzeo2Z0+QQoDLiRcsSSS/XMhAidNZyauxLPg0Da8aGNgdqz0tl4i66j2S2OqHdL8LS5Rd
25 lq8+Q8KkK8Eu+OIBkmT8UgPXybefgTkWt+e82r+lgJHKqnJh8aXFFOqadtNyFrts8/Jph9OV
26 EZUpa6epeksaX3HekigzRD4CZrIingkuKSoMxpAI45nKPfpNptHb0AKPbZNDMnONzN1H548z
27 pGsPdY0ffGsWVpvinmY6jDWcPKUBgr3zn97f21Q57pVnvVJht1EEgGBQoCDoa3wEjtVNKl8k
28 BwJmMV5K/f4EUWazs3dcNFKYvdoecIeEAnJmeQ1j1KQUOICGqPGrK3uVoLNdxM9FbJHTNIdn
29 YbW2a2h7jcj6dk0LIKyr0r/33QtmKK0jdJtf3HpqPZhB8UmStnoAJCBRj6f8/o+w6JEYywpf
30 AXEa3begV95iTZFoSWSXgJyGNlVt+cvPX+H+7BxIFrbkpTGa3sgTye6NFYNqUsnBd9+CB+gB
31 5qQPKAUotaZBuVV7
32
33 /
Package body created.
SQL>
In 10g and later releases of Oracle a second method of wrapping PL/SQL source code is available with the DBMS_DDL.WRAP function. This is designed for use with dynamic PL/SQL statements:
declare
ddl varchar2(32767);
begin
ddl := 'create or replace procedure ...';
execute immediate dbms_ddl.wrap(ddl); -- 'Wraps' the procedure then executes it
end;
/
If you're concerned with unauthorized persons viewing sensitive PL/SQL source code then the wrap utility is probably something you should investigate. Remember, though, that you CAN'T* 'unwrap' the wrapped code later, so save your original source code somewhere safe for when you next need it.* There are third-party unwrap tools for 9iR2 and earlier releases of Oracle, but, again, these are not supported by Oracle Corporation. As a result of this the wrap mechanism in 10g and later releases has changed and these tools will not work on wrapped code in any release after 9.2.0.x. You're welcome to search google.com for them; I'll not supply any links to them here.
And, that's a wrap.
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