(SQL Server) RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context.

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
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    -- This example assumes the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

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

    -- First load a public key object with a public key.
    -- In this case, we'll load it from a file.
    DECLARE @pubkey int
    -- Use "Chilkat_9_5_0.PublicKey" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.PublicKey', @pubkey OUT

    DECLARE @success int
    EXEC sp_OAMethod @pubkey, 'LoadFromFile', @success OUT, 'qa_data/pem/rsa_public.pem'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @pubkey, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rsa
        EXEC @hr = sp_OADestroy @pubkey
        RETURN
      END

    -- RSA encryption is limited to small amounts of data. The limit
    -- is typically a few hundred bytes and is based on the key size and
    -- padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
    -- encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
    DECLARE @plainText nvarchar(4000)
    SELECT @plainText = 'Time is an illusion. Lunchtime doubly so.'

    -- Import the public key to be used for encrypting.
    EXEC sp_OAMethod @rsa, 'ImportPublicKeyObj', @success OUT, @pubkey

    -- To get OAEP padding, set the OaepPadding property:
    EXEC sp_OASetProperty @rsa, 'OaepPadding', 1

    -- To use SHA1 or SHA-256, set the OaepHash property
    EXEC sp_OASetProperty @rsa, 'OaepHash', 'sha256'
    -- for SHA1 --
    EXEC sp_OASetProperty @rsa, 'OaepHash', 'sha1'

    -- Indicate we'll want hex output
    EXEC sp_OASetProperty @rsa, 'EncodingMode', 'hex'

    -- Encrypt..
    DECLARE @usePrivateKey int
    SELECT @usePrivateKey = 0
    DECLARE @encryptedStr nvarchar(4000)
    EXEC sp_OAMethod @rsa, 'EncryptStringENC', @encryptedStr OUT, @plainText, @usePrivateKey

    PRINT @encryptedStr

    -- -------------------------------------------------
    -- Now decrypt with the matching private key.
    DECLARE @rsa2 int
    -- Use "Chilkat_9_5_0.Rsa" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Rsa', @rsa2 OUT

    DECLARE @privKey int
    -- Use "Chilkat_9_5_0.PrivateKey" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.PrivateKey', @privKey OUT

    EXEC sp_OAMethod @privKey, 'LoadEncryptedPem', @success OUT, 'qa_data/pem/rsa_passwd.pem', 'passwd'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @privKey, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rsa
        EXEC @hr = sp_OADestroy @pubkey
        EXEC @hr = sp_OADestroy @rsa2
        EXEC @hr = sp_OADestroy @privKey
        RETURN
      END

    EXEC sp_OAMethod @rsa2, 'ImportPrivateKeyObj', @success OUT, @privKey

    -- Make sure we have the same settings used for encryption.
    EXEC sp_OASetProperty @rsa2, 'OaepPadding', 1
    EXEC sp_OASetProperty @rsa2, 'EncodingMode', 'hex'
    EXEC sp_OASetProperty @rsa2, 'OaepHash', 'sha1'

    DECLARE @originalStr nvarchar(4000)
    EXEC sp_OAMethod @rsa2, 'DecryptStringENC', @originalStr OUT, @encryptedStr, 1


    PRINT @originalStr

    EXEC @hr = sp_OADestroy @rsa
    EXEC @hr = sp_OADestroy @pubkey
    EXEC @hr = sp_OADestroy @rsa2
    EXEC @hr = sp_OADestroy @privKey


END
GO