(SQL Server) HOTP Algorithm: HMAC-Based One-Time Password Algorithm

Demonstrates how to generate an HMAC one-time password (HOTP) as specified in RFC 4226.

Note: This example requires Chilkat v9.5.0.77 or greater.

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 requires 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

    -- Duplicate the following results from RFC 4226

    -- Appendix D - HOTP Algorithm: Test Values
    -- 
    --   The following test data uses the ASCII string
    --   "12345678901234567890" for the secret:
    -- 
    --   Secret = 0x3132333435363738393031323334353637383930
    -- 
    --                     Truncated
    --   Count    Hexadecimal    Decimal        HOTP
    --   0        4c93cf18       1284755224     755224
    --   1        41397eea       1094287082     287082
    --   2         82fef30        137359152     359152
    --   3        66ef7655       1726969429     969429
    --   4        61c5938a       1640338314     338314
    --   5        33c083d4        868254676     254676
    --   6        7256c032       1918287922     287922
    --   7         4e5b397         82162583     162583
    --   8        2823443f        673399871     399871
    --   9        2679dc69        645520489     520489

    DECLARE @secret nvarchar(4000)
    SELECT @secret = '12345678901234567890'
    DECLARE @count int

    SELECT @count = 0
    WHILE @count <= 9
      BEGIN
        DECLARE @counterHex nvarchar(4000)
        EXEC sp_OAMethod @crypt, 'EncodeInt', @counterHex OUT, @count, 8, 0, 'hex'
        DECLARE @hotp nvarchar(4000)
        EXEC sp_OAMethod @crypt, 'Hotp', @hotp OUT, @secret, 'ascii', @counterHex, 6, -1, 'sha1'


        PRINT @count + '  HOTP = ' + @hotp
        SELECT @count = @count + 1
      END

    -- Output is:
    -- 0  HOTP = 755224
    -- 1  HOTP = 287082
    -- 2  HOTP = 359152
    -- 3  HOTP = 969429
    -- 4  HOTP = 338314
    -- 5  HOTP = 254676
    -- 6  HOTP = 287922
    -- 7  HOTP = 162583
    -- 8  HOTP = 399871
    -- 9  HOTP = 520489

    EXEC @hr = sp_OADestroy @crypt


END
GO