dbo.sample.prc
---------------------------------
CREATE PROCEDURE hello
WITH ENCRYPTION
AS
PRINT \'Hello World!\'
GO

exec sp_helptext hello
GO

exec dbo.DECRYPTSP2K \'hello\'
GO

exec sp_helptext hello
GO
----------------------------------

dbo.DECRYPTSP2K.prc
----------------------------------
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS OFF
GO

CREATE PROCEDURE DECRYPTSP2K (@objName varchar(50))
--INPUT: object name (stored procedure,
--
-- view or trigger)
--Original idea: shoeboy <shoeboy@a
-- dequacy.org>
--Copyright ?1999-2002 SecurityFocus
--adapted by Joseph Gama
--Planet Source Code, my employer and my
--
-- self are not responsible for the use
--     of
-- this code
--This code is provided as is and for ed
--
-- ucational purposes only
--Please test it and share your results
AS
DECLARE @a nvarchar(4000), @b nvarchar(4000), @c nvarchar(4000), @d
nvarchar(4000), @i int, @t bigint
--get encrypted data
SET @a=(SELECT ctext FROM syscomments WHERE id = object_id(@objName))
SET @b=\'ALTER PROCEDURE \'+ @objName +\' WITH ENCRYPTION AS \'+REPLICATE(\'-\',
4000-62)
EXECUTE (@b)
--get encrypted bogus SP
SET @c=(SELECT ctext FROM syscomments WHERE id = object_id(@objName))
SET @b=\'CREATE PROCEDURE \'+ @objName +\' WITH ENCRYPTION AS \'+REPLICATE(\'-\',
4000-62)
--start counter
SET @i=1
--fill temporary variable
SET @d = replicate(N\'A\', (datalength(@a) / 2))
--loop
WHILE @i<=datalength(@a)/2
BEGIN
--xor original+bogus+bogus encrypted
SET @d = stuff(@d, @i, 1,
NCHAR(UNICODE(substring(@a, @i, 1)) ^
(UNICODE(substring(@b, @i, 1)) ^
UNICODE(substring(@c, @i, 1)))))
SET @i=@i+1
END
--drop original SP
EXECUTE (\'drop PROCEDURE \'+ @objName)
--remove encryption
--try to preserve case
SET @d=REPLACE((@d),\'WITH ENCRYPTION\', \'\')
SET @d=REPLACE((@d),\'With Encryption\', \'\')
SET @d=REPLACE((@d),\'with encryption\', \'\')
IF CHARINDEX(\'WITH ENCRYPTION\',UPPER(@d) )>0
SET @d=REPLACE(UPPER(@d),\'WITH ENCRYPTION\', \'\')
--replace SP
execute( @d)

GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO
----------------------------------------------------