(SQL Server) HMAC with SHA256

Demonstrates how to compute a HMAC SHA256 keyed-hash message authentication code.

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

    -- The output will be Hex, so set the EncodingMode:
    EXEC sp_OASetProperty @crypt, 'EncodingMode', 'hex'

    -- Set the hash algorithm:
    -- Choices are: md5, sha-1, sha256, sha384, sha512, md2, haval
    EXEC sp_OASetProperty @crypt, 'HashAlgorithm', 'sha256'

    DECLARE @mac nvarchar(4000)

    -- Set the HMAC key:
    EXEC sp_OAMethod @crypt, 'SetHmacKeyEncoded', NULL, 'The_API_Secret', 'ascii'
    EXEC sp_OAMethod @crypt, 'HmacStringENC', @mac OUT, 'The quick brown fox jumps over the lazy dog'

    PRINT @mac

    EXEC @hr = sp_OADestroy @crypt


END
GO