(SQL Server) Get Certificate CRL Distribution Points

Demonstrates how to get a certificate's CRL Distribution Points extension data (assuming it exists). In the vast majority of cases, there will be one CRL Distribution Point.

Note: This example requires Chilkat v9.5.0.76 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
    DECLARE @iTmp0 int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @cert int
    EXEC @hr = sp_OACreate 'Chilkat_9_5_0.Cert', @cert OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @success int
    EXEC sp_OAMethod @cert, 'LoadFromFile', @success OUT, 'qa_data/certs/test_haswdt.cer'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @cert, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @cert
        RETURN
      END

    -- Get the CRL Distribution Points extension, which is at OID 2.5.29.31
    DECLARE @extensionXmlStr nvarchar(4000)
    EXEC sp_OAMethod @cert, 'GetExtensionAsXml', @extensionXmlStr OUT, '2.5.29.31'
    EXEC sp_OAGetProperty @cert, 'LastMethodSuccess', @iTmp0 OUT
    IF @iTmp0 = 0
      BEGIN

        PRINT 'Certificate does not have the CDP extension.'
        EXEC @hr = sp_OADestroy @cert
        RETURN
      END

    DECLARE @xml int
    EXEC @hr = sp_OACreate 'Chilkat_9_5_0.Xml', @xml OUT

    EXEC sp_OAMethod @xml, 'LoadXml', @success OUT, @extensionXmlStr

    -- See what we have..
    EXEC sp_OAMethod @xml, 'GetXml', @sTmp0 OUT
    PRINT @sTmp0

    -- We should get XML like this:

    -- <?xml version="1.0" encoding="utf-8" ?>
    -- <sequence>
    --     <sequence>
    --         <contextSpecific tag="0" constructed="1">
    --             <contextSpecific tag="0" constructed="1">
    --                 <contextSpecific tag="6" constructed="0">aHR0cDovL2NybC5jb21vZG9jYS5jb20vQ09NT0RPUlNBQ2xpZW50QXV0aGVudGljYXRpb25hbmRTZWN1
    -- cmVFbWFpbENBLmNybA==</contextSpecific>
    --             </contextSpecific>
    --         </contextSpecific>
    --     </sequence>
    -- </sequence>
    -- 

    -- Assuming there is one CRL Distribution Point...
    DECLARE @sbDistPoint int
    EXEC @hr = sp_OACreate 'Chilkat_9_5_0.StringBuilder', @sbDistPoint OUT

    EXEC sp_OAMethod @xml, 'GetChildContentSb', @success OUT, 'sequence|contextSpecific|contextSpecific|contextSpecific', @sbDistPoint
    IF @success = 1
      BEGIN
        EXEC sp_OAMethod @sbDistPoint, 'Decode', @success OUT, 'base64', 'utf-8'

        EXEC sp_OAMethod @sbDistPoint, 'GetAsString', @sTmp0 OUT
        PRINT 'CRL Distribution Point:  ' + @sTmp0
      END

    -- Sample output:
    -- CRL Distribution Point:  http://crl.comodoca.com/COMODORSAClientAuthenticationandSecureEmailCA.crl

    EXEC @hr = sp_OADestroy @cert
    EXEC @hr = sp_OADestroy @xml
    EXEC @hr = sp_OADestroy @sbDistPoint


END
GO