(SQL Server) RSA Sign utf-8 Byte Representation of String

Demontstrates how to sign the utf-8 byte representation of a string.

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 requires the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    -- Load an RSA private key for signing.
    DECLARE @privKey int
    -- Use "Chilkat_9_5_0.PrivateKey" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.PrivateKey', @privKey OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @success int
    EXEC sp_OAMethod @privKey, 'LoadEncryptedPemFile', @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 @privKey
        RETURN
      END

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

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

    DECLARE @originalData nvarchar(4000)
    SELECT @originalData = 'This is the string to be hashed an RSA signed.'

    -- Indicate that we want the utf-8 byte representation of the string to be signed
    EXEC sp_OASetProperty @rsa, 'Charset', 'utf-8'

    -- We want the RSA signature in base64 format
    EXEC sp_OASetProperty @rsa, 'EncodingMode', 'base64'

    DECLARE @sigBase64 nvarchar(4000)
    EXEC sp_OAMethod @rsa, 'SignStringENC', @sigBase64 OUT, @originalData, 'sha256'

    PRINT @sigBase64

    EXEC @hr = sp_OADestroy @privKey
    EXEC @hr = sp_OADestroy @rsa


END
GO