(SQL Server) Generate an RSA Key and Get as Base64 DER

Demonstrates how to generate a 2048-bit RSA key and return the public and private parts as unencrypted Base64 encoded DER.

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

    -- Generate a 2048-bit key.  Chilkat RSA supports
    DECLARE @success int
    EXEC sp_OAMethod @rsa, 'GenerateKey', @success OUT, 2048
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @rsa, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @rsa
        RETURN
      END

    -- Get the public part of the key.
    DECLARE @pubKey int
    EXEC sp_OAMethod @rsa, 'ExportPublicKeyObj', @pubKey OUT

    -- There are two possible formats for representing the RSA public key 
    -- in ASN.1 (DER).  The possible formats are PKCS1 and PKCS8.
    -- We can get either by setting bChoosePkcs1 to 1 or 0.
    DECLARE @bChoosePkcs1 int
    SELECT @bChoosePkcs1 = 1
    DECLARE @pubKeyBase64Der nvarchar(4000)
    EXEC sp_OAMethod @pubKey, 'GetEncoded', @pubKeyBase64Der OUT, @bChoosePkcs1, 'base64'

    PRINT 'Public Key Base64 DER:'

    PRINT @pubKeyBase64Der

    EXEC @hr = sp_OADestroy @pubKey

    -- Now get the private key as Base64 DER:
    -- Get the private part of the key.
    -- (Note: A public key is actually just a subset of the private key.  
    --  If you have the private key, you also have the public key.
    --  Thus Chilkat provides a method to get the public key from the private key.)
    DECLARE @privKey int
    EXEC sp_OAMethod @rsa, 'ExportPrivateKeyObj', @privKey OUT

    -- Again, we can get PKCS1 or PKCS8, but with different methods:
    DECLARE @privKeyPkcs1 nvarchar(4000)
    EXEC sp_OAMethod @privKey, 'GetPkcs1ENC', @privKeyPkcs1 OUT, 'base64'

    PRINT 'Private Key PKCS1 Base64 DER:'

    PRINT @privKeyPkcs1

    DECLARE @privKeyPkcs8 nvarchar(4000)
    EXEC sp_OAMethod @privKey, 'GetPkcs8ENC', @privKeyPkcs8 OUT, 'base64'

    PRINT 'Private Key PKCS8 Base64 DER:'

    PRINT @privKeyPkcs8

    EXEC @hr = sp_OADestroy @privKey


    EXEC @hr = sp_OADestroy @rsa


END
GO