SQL Server

RSA Sign an Encoded Hash

See more RSA Examples

Demonstrates signing a hash (e.g., SHA256) provided as an encoded string (e.g., base64 or hex). 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
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    -- Assuming the smartcard/USB token is installed with the correct drivers from the manufacturer,
    -- this code can work on multiple platforms including Windows, MacOS, Linux, and iOS.

    -- Chilkat automatically detects and determines the way in which the HSM is used,
    -- which can be by PKCS11, Apple Keychain, Microsoft CNG / Crypto API, or ScMinidriver.

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

    -- Set the token/smartcard PIN prior to loading.
    EXEC sp_OASetProperty @cert, 'SmartCardPin', '123456'

    -- Specify the certificate by its common name.
    EXEC sp_OAMethod @cert, 'LoadFromSmartcard', @success OUT, 'cn=chilkat-rsa-2048'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @cert, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @cert
        RETURN
      END


    EXEC sp_OAGetProperty @cert, 'SubjectCN', @sTmp0 OUT
    PRINT 'Signing with the private key for this cert: ' + @sTmp0

    -- Create data to be hashed and signed.
    DECLARE @bd int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @bd OUT

    DECLARE @i int

    SELECT @i = 0
    WHILE @i <= 100
      BEGIN
        EXEC sp_OAMethod @bd, 'AppendEncoded', @success OUT, '000102030405060708090A0B0C0D0E0F', 'hex'
        SELECT @i = @i + 1
      END

    DECLARE @rsa int
    EXEC @hr = sp_OACreate 'Chilkat.Rsa', @rsa OUT

    -- Use the certificate's private key for signing.
    EXEC sp_OAMethod @rsa, 'SetX509Cert', @success OUT, @cert, 1
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @rsa, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @cert
        EXEC @hr = sp_OADestroy @bd
        EXEC @hr = sp_OADestroy @rsa
        RETURN
      END

    -- We'll first compute the hash and then pass the encoded hash to be signed.
    DECLARE @sha256_base64 nvarchar(4000)
    EXEC sp_OAMethod @bd, 'GetHash', @sha256_base64 OUT, 'sha256', 'base64'

    PRINT 'sha256 hash in base64 format: ' + @sha256_base64

    -- Pass in the base64 hash and return a base64 signature.
    EXEC sp_OASetProperty @rsa, 'EncodingMode', 'base64'
    DECLARE @rsaSig_base64 nvarchar(4000)
    EXEC sp_OAMethod @rsa, 'SignHashENC', @rsaSig_base64 OUT, @sha256_base64, 'sha256'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @rsa, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @cert
        EXEC @hr = sp_OADestroy @bd
        EXEC @hr = sp_OADestroy @rsa
        RETURN
      END


    PRINT 'RSA signature as base64: ' + @rsaSig_base64

    EXEC @hr = sp_OADestroy @cert
    EXEC @hr = sp_OADestroy @bd
    EXEC @hr = sp_OADestroy @rsa


END
GO