SQL Server

Fortuna PRNG Generate Random Encoded

See more PRNG Examples

Demonstrates how to generate random bytes using the Fortuna PRNG. The random bytes are returned in an encoded string (using an encoding such as hex, base64, base58, etc.) 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
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

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

    SELECT @success = 0

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

    -- Before beginning to generate random data, 
    -- the PRNG (Pseudo Random Number Generator) should
    -- be seeded with real random data (also known as "entropy").

    -- Note: Accumulating real random data can be difficult
    -- and time-consuming to collect.  It is for this reason
    -- that pseudorandom data (i.e. a PRNG) is used.  The pseudorandom data generator
    -- is seeded with entropy.  In addition, new entropy can (and should)
    -- be periodically added as more pseudorandom data is generated.

    -- Get 32 bytes of system entropy.  On Linux/Unix systems, this reads
    -- from /dev/random.  On MS Windows systems, it uses the Crypto API's 
    -- CryptGenRandom function.
    DECLARE @strEntropy nvarchar(4000)
    EXEC sp_OAMethod @fortuna, 'GetEntropy', @strEntropy OUT, 32, 'hex'
    EXEC sp_OAGetProperty @fortuna, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 <> 1
      BEGIN
        EXEC sp_OAGetProperty @fortuna, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @fortuna
        RETURN
      END

    -- Seed the PRNG with this entropy:
    EXEC sp_OAMethod @fortuna, 'AddEntropy', @success OUT, @strEntropy, 'hex'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @fortuna, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @fortuna
        RETURN
      END

    -- Generate some random data:
    DECLARE @strRandHex nvarchar(4000)
    EXEC sp_OAMethod @fortuna, 'GenRandom', @strRandHex OUT, 16, 'hex'
    DECLARE @strRandBase64 nvarchar(4000)
    EXEC sp_OAMethod @fortuna, 'GenRandom', @strRandBase64 OUT, 22, 'base64'
    DECLARE @strRandBase58 nvarchar(4000)
    EXEC sp_OAMethod @fortuna, 'GenRandom', @strRandBase58 OUT, 32, 'base58'


    PRINT 'hex random bytes: ' + @strRandHex

    PRINT 'base64 random bytes: ' + @strRandBase64

    PRINT 'base58 random bytes: ' + @strRandBase58

    EXEC @hr = sp_OADestroy @fortuna


END
GO