(SQL Server) Get Public Key from CSR

Demonstrates how to get the public key from a CSR.

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

    DECLARE @pem int
    -- Use "Chilkat_9_5_0.Pem" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Pem', @pem OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- No password is required.  Pass an empty password string..
    DECLARE @noPassword nvarchar(4000)
    SELECT @noPassword = ''
    DECLARE @success int
    EXEC sp_OAMethod @pem, 'LoadPemFile', @success OUT, 'qa_data/csr/csr2.pem', @noPassword
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @pem, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @pem
        RETURN
      END

    DECLARE @strBase64 nvarchar(4000)
    EXEC sp_OAMethod @pem, 'GetEncodedItem', @strBase64 OUT, 'csr', '', 'base64', 0

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

    EXEC sp_OAMethod @asn, 'LoadEncoded', @success OUT, @strBase64, 'base64'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @asn, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @pem
        EXEC @hr = sp_OADestroy @asn
        RETURN
      END

    -- Convert the ASN.1 to XML.
    DECLARE @xml int
    -- Use "Chilkat_9_5_0.Xml" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Xml', @xml OUT

    EXEC sp_OAMethod @asn, 'AsnToXml', @sTmp0 OUT
    EXEC sp_OAMethod @xml, 'LoadXml', @success OUT, @sTmp0
    EXEC sp_OAMethod @xml, 'GetXml', @sTmp0 OUT
    PRINT @sTmp0

    PRINT '----'

    DECLARE @strModulusHex nvarchar(4000)
    EXEC sp_OAMethod @xml, 'GetChildContent', @strModulusHex OUT, 'bits'

    PRINT 'strModulusHex = ' + @strModulusHex

    PRINT '----'

    -- We need the modulus as base64.
    DECLARE @bd int
    -- Use "Chilkat_9_5_0.BinData" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @bd OUT

    EXEC sp_OAMethod @bd, 'AppendEncoded', @success OUT, @strModulusHex, 'hex'
    DECLARE @modulus64 nvarchar(4000)
    EXEC sp_OAMethod @bd, 'GetEncoded', @modulus64 OUT, 'base64'

    PRINT 'modulus64 = ' + @modulus64

    PRINT '----'

    -- Build the XML for the public key.
    DECLARE @xmlPubKey int
    -- Use "Chilkat_9_5_0.Xml" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Xml', @xmlPubKey OUT

    EXEC sp_OASetProperty @xmlPubKey, 'Tag', 'RSAPublicKey'
    EXEC sp_OAMethod @xmlPubKey, 'UpdateChildContent', NULL, 'Modulus', @modulus64
    -- The RSA exponent will always be decimal 65537 (base64 = AQAB)
    EXEC sp_OAMethod @xmlPubKey, 'UpdateChildContent', NULL, 'Exponent', 'AQAB'


    PRINT 'RSA public key as XML:'
    EXEC sp_OAMethod @xmlPubKey, 'GetXml', @sTmp0 OUT
    PRINT @sTmp0

    PRINT '----'

    -- Load the XML into a Chilkat public key object.
    DECLARE @pubkey int
    -- Use "Chilkat_9_5_0.PublicKey" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.PublicKey', @pubkey OUT

    EXEC sp_OAMethod @xmlPubKey, 'GetXml', @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 @pem
        EXEC @hr = sp_OADestroy @asn
        EXEC @hr = sp_OADestroy @xml
        EXEC @hr = sp_OADestroy @bd
        EXEC @hr = sp_OADestroy @xmlPubKey
        EXEC @hr = sp_OADestroy @pubkey
        RETURN
      END

    -- Show the public key as PEM.
    DECLARE @preferPkcs1 int
    SELECT @preferPkcs1 = 1
    EXEC sp_OAMethod @pubkey, 'GetPem', @sTmp0 OUT, @preferPkcs1
    PRINT @sTmp0

    EXEC @hr = sp_OADestroy @pem
    EXEC @hr = sp_OADestroy @asn
    EXEC @hr = sp_OADestroy @xml
    EXEC @hr = sp_OADestroy @bd
    EXEC @hr = sp_OADestroy @xmlPubKey
    EXEC @hr = sp_OADestroy @pubkey


END
GO