(Visual FoxPro) 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

LOCAL loCert
LOCAL lnSuccess
LOCAL lcExtensionXmlStr
LOCAL loXml
LOCAL loSbDistPoint

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Cert')
loCert = CreateObject('Chilkat.Cert')

lnSuccess = loCert.LoadFromFile("qa_data/certs/test_haswdt.cer")
IF (lnSuccess <> 1) THEN
    ? loCert.LastErrorText
    RELEASE loCert
    CANCEL
ENDIF

* Get the CRL Distribution Points extension, which is at OID 2.5.29.31
lcExtensionXmlStr = loCert.GetExtensionAsXml("2.5.29.31")
IF (loCert.LastMethodSuccess = 0) THEN
    ? "Certificate does not have the CDP extension."
    RELEASE loCert
    CANCEL
ENDIF

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Xml')
loXml = CreateObject('Chilkat.Xml')
loXml.LoadXml(lcExtensionXmlStr)

* See what we have..
? loXml.GetXml()

* 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...
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringBuilder')
loSbDistPoint = CreateObject('Chilkat.StringBuilder')
lnSuccess = loXml.GetChildContentSb("sequence|contextSpecific|contextSpecific|contextSpecific",loSbDistPoint)
IF (lnSuccess = 1) THEN
    loSbDistPoint.Decode("base64","utf-8")
    ? "CRL Distribution Point:  " + loSbDistPoint.GetAsString()
ENDIF

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

RELEASE loCert
RELEASE loXml
RELEASE loSbDistPoint