SQL Server

56-bit DES Encryption, ECB, CBC modes

See more Encryption Examples

Demonstrates the older 56-bit DES encryption in ECB and CBC modes. SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- This example assumes the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    DECLARE @crypt int
    EXEC @hr = sp_OACreate 'Chilkat.Crypt2', @crypt OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Specify DES for the encryption algorithm:
    EXEC sp_OASetProperty @crypt, 'CryptAlgorithm', 'des'

    -- CipherMode may be "ecb" or "cbc"
    EXEC sp_OASetProperty @crypt, 'CipherMode', 'cbc'

    -- Keylength is 64 bits (56 bits + 8 parity bits)
    EXEC sp_OASetProperty @crypt, 'KeyLength', 64

    -- The padding scheme determines the contents of the bytes
    -- that are added to pad the result to a multiple of the
    -- encryption algorithm's block size.  DES has a block
    -- size of 8 bytes, so encrypted output is always
    -- a multiple of 8.
    EXEC sp_OASetProperty @crypt, 'PaddingScheme', 0

    -- EncodingMode specifies the encoding of the output for
    -- encryption, and the input for decryption.
    -- It may be "hex", "url", "base64", or "quoted-printable".
    EXEC sp_OASetProperty @crypt, 'EncodingMode', 'hex'

    -- An initialization vector is required if using CBC or CFB modes.
    -- ECB mode does not use an IV.
    -- The length of the IV is equal to the algorithm's block size.
    -- It is NOT equal to the length of the key.
    DECLARE @ivHex nvarchar(4000)
    SELECT @ivHex = '0001020304050607'
    EXEC sp_OAMethod @crypt, 'SetEncodedIV', NULL, @ivHex, 'hex'

    -- The secret key must equal the size of the key.  For 
    -- DES, the key must be 8 bytes (i.e. 64-bits).
    DECLARE @keyHex nvarchar(4000)
    SELECT @keyHex = '0001020304050607'
    EXEC sp_OAMethod @crypt, 'SetEncodedKey', NULL, @keyHex, 'hex'

    -- Encrypt a string...
    -- The input string is 44 ANSI characters (i.e. 44 bytes), so
    -- the output should be 48 bytes (a multiple of 8).
    -- Because the output is a hex string, it should
    -- be 96 characters long (2 chars per byte).
    DECLARE @encStr nvarchar(4000)
    EXEC sp_OAMethod @crypt, 'EncryptStringENC', @encStr OUT, 'The quick brown fox jumps over the lazy dog.'

    PRINT @encStr

    -- Now decrypt:
    DECLARE @decStr nvarchar(4000)
    EXEC sp_OAMethod @crypt, 'DecryptStringENC', @decStr OUT, @encStr

    PRINT @decStr

    EXEC @hr = sp_OADestroy @crypt


END
GO