(SQL Server) PBES2 Password-Based Encryption (PBE)

Demonstrates how to implement password-based encryption according to the PKCS #5 v2.0: Password-Based Cryptography Standard (published by RSA Laboratories). This example uses PBES2, which ise based on the PBKDF2 function and an underlying block cipher such as RC2, DES, etc.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- 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
    -- Use "Chilkat_9_5_0.Crypt2" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Crypt2', @crypt OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Set properties for PBES2 encryption:

    EXEC sp_OASetProperty @crypt, 'CryptAlgorithm', 'pbes2'
    EXEC sp_OASetProperty @crypt, 'PbesPassword', 'mySecretPassword'

    -- Set the underlying PBE algorithm (and key length):
    EXEC sp_OASetProperty @crypt, 'PbesAlgorithm', 'rc2'
    EXEC sp_OASetProperty @crypt, 'KeyLength', 128
    -- Only required for the RC2 algorithm:
    EXEC sp_OASetProperty @crypt, 'Rc2EffectiveKeyLength', 128

    -- By definition, the block encryption algorithm (RC2 or whichever
    -- was selected) will run in CBC mode.  Therefore, we need
    -- an IV.  The IV is equal in length to the block size of the
    -- algorithm.  RC2 has a block size of 8 bytes (regardless of
    -- key length), so set the IV to some value that is 8 bytes 
    -- in length:
    EXEC sp_OAMethod @crypt, 'SetEncodedIV', NULL, '0000000000000000', 'hex'

    -- Give it some salt:
    EXEC sp_OAMethod @crypt, 'SetEncodedSalt', NULL, '0102030405060708', 'hex'

    -- A higher iteration count makes the algorithm more
    -- computationally expensive and therefore exhaustive
    -- searches (for breaking the encryption) is more difficult:
    EXEC sp_OASetProperty @crypt, 'IterationCount', 1024

    -- A hash algorithm needs to be set for PBES2:
    EXEC sp_OASetProperty @crypt, 'HashAlgorithm', 'sha1'

    -- Indicate that the encrypted bytes should be returned
    -- as a hex string:
    EXEC sp_OASetProperty @crypt, 'EncodingMode', 'hex'

    DECLARE @plainText nvarchar(4000)
    SELECT @plainText = 'To be encrypted.'

    DECLARE @encryptedText nvarchar(4000)
    EXEC sp_OAMethod @crypt, 'EncryptStringENC', @encryptedText OUT, @plainText


    PRINT @encryptedText

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


    PRINT @decryptedText

    EXEC @hr = sp_OADestroy @crypt


END
GO