(SQL Server) Compute JWK Thumbprint for RSA and EC Public Keys

Demonstrates how to compute a JSON Web Key thumbprint for a public key (RSA or ECC).

Note: This example requires Chilkat v9.5.0.66 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
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @pubKey int
    -- Use "Chilkat_9_5_0.PublicKey" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.PublicKey', @pubKey OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- A public key can be loaded from any format (binary DER, PEM, etc.)
    -- This example will load the public keys from JWK format, 
    -- and will then compute the JWK thumbprint.

    -- First do it for an RSA public key...

    DECLARE @sb int
    -- Use "Chilkat_9_5_0.StringBuilder" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.StringBuilder', @sb OUT

    DECLARE @success int
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '{'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '"kty": "RSA",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '"n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAt'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, 'VT86zwu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMstn6'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '4tZ_2W-5JsGY4Hc5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FD'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, 'W2QvzqY368QQMicAtaSqzs8KJZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n9'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '1CbOpbISD08qNLyrdkt-bFTWhAI4vMQFh6WeZu0fM4lFd2NcRwr3XPksINH'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, 'aQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKnqDKgw",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '"e": "AQAB",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '"alg": "RS256",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '"kid": "2011-04-29"'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '}'

    -- The JWK format is automatically detected..
    DECLARE @success int
    EXEC sp_OAMethod @sb, 'GetAsString', @sTmp0 OUT
    EXEC sp_OAMethod @pubKey, 'LoadFromString', @success OUT, @sTmp0
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @pubKey, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @pubKey
        EXEC @hr = sp_OADestroy @sb
        RETURN
      END

    -- Get the JWK thumbprint (using SHA256)

    EXEC sp_OAMethod @pubKey, 'GetJwkThumbprint', @sTmp0 OUT, 'SHA256'
    PRINT 'JWK thumbprint: ' + @sTmp0

    -- Output:
    -- JWK thumbprint: NzbLsXh8uDCcd-6MNwXF4W_7noWXFZAfHkxZsRGC9Xs

    -- --------------------------------------------------------------
    -- Now let's do an EC public key:
    EXEC sp_OAMethod @sb, 'Clear', NULL
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '{ '
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '  "kty": "EC",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '  "crv": "P-256",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '  "x": "tDeeYABgKEAbWicYPCEEI8sP4SRIhHKcHDW7VqrB4LA",'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '  "y": "J08HOoIZ0rX2Me3bNFZUltfxIk1Hrc8FsLu8VaSxsMI"'
    EXEC sp_OAMethod @sb, 'Append', @success OUT, '}'

    EXEC sp_OAMethod @sb, 'GetAsString', @sTmp0 OUT
    EXEC sp_OAMethod @pubKey, 'LoadFromString', @success OUT, @sTmp0
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @pubKey, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @pubKey
        EXEC @hr = sp_OADestroy @sb
        RETURN
      END

    -- Get the JWK thumbprint (using SHA256)

    EXEC sp_OAMethod @pubKey, 'GetJwkThumbprint', @sTmp0 OUT, 'SHA256'
    PRINT 'JWK thumbprint: ' + @sTmp0

    -- Output:
    -- JWK thumbprint: 8fm8079s3nu4FLV_7dVJoJ69A8XCXn7Za2mtaWCnxR4

    EXEC @hr = sp_OADestroy @pubKey
    EXEC @hr = sp_OADestroy @sb


END
GO