SQL Server

HOTP Algorithm: HMAC-Based One-Time Password Algorithm

See more Encryption Examples

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.

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

    DECLARE @crypt int
    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