Hi Dominick,

Actually I need to convert the raw binary data format of .Certificate
property to a String formatted like
Request.ClientCertificate("CERTIFICATE"). But I don't know how to get it.

Let me explain the situation:

I'm working with several CAs to perform client authentication based on
certificates. Of course, I would like to check the revocation status of the
certificate before granting access for users to the application.

I thought in developing a web service. This web service takes the
.Certificate property base-64 encoded, loads a CAPICOM Certificate object
and checks the revocation status:
<WebMethod()> Public Function ValidaCertificado(ByVal certB64 As String) As
Integer

Dim oCert As CAPICOM.CertificateClass

oCert = New CAPICOM.CertificateClass

oCert.Import(certB64)

oCert.IsValid.CheckFlag =
CAPICOM.CAPICOM_CHECK_FLAG.CAPICOM_CHECK_TRUSTED_ROOT Or _

CAPICOM.CAPICOM_CHECK_FLAG.CAPICOM_CHECK_TIME_VALIDITY Or _

CAPICOM.CAPICOM_CHECK_FLAG.CAPICOM_CHECK_SIGNATURE_VALIDITY Or _

CAPICOM.CAPICOM_CHECK_FLAG.CAPICOM_CHECK_ONLINE_REVOCATION_STATUS

If oCert.IsValid.Result Then

'CERTIFICATE IS VALID!

Return 1

Else

Dim chain As New CAPICOM.Chain

chain.Build(oCert)

If CAPICOM.Constants.CAPICOM_TRUST_IS_REVOKED And chain.Status Then

'AT LEAST ONE CERTIFICATE IN THE CHAIN HAS BEEN REVOKED

Return 0

End If

If CAPICOM.Constants.CAPICOM_TRUST_REVOCATION_STATUS_UNKNOWN And
chain.Status Then

'THE REVOCATION STATUS COULD NOT BE DETERMINED

return 0

End If

End If

...

It works for every CAs, excepting one.

This CA emits its certificates with a CRL Distribution Point malformed. For
example:

[1]CRL Distribution Point

Distribution Point Name:

Full Name:

Directory Address:

CN=CRL1942

OU=FNMT Clase 2 CA

O=FNMT

C=ES

As you can see, there is not reference to the server where the LDAP
directory is stored.

This field only contains the necessary information to determine the
revocation status using a module provided by the CA (They consider it as a
service and, of course, it's not a free of charge service).

The function provided by this CA to validate the certificate expects to
receive the certificate as a string like the returned by
Request.ClientCertificate("CERTIFICATE").

That is the reason why I want to convert the raw binary format field
.Certificate into a String like Request.ClientCertificate("CERTIFICATE"). In
this way, my web service will be able to determine the revocation status of
every certificate.

Any idea?

Thanks in advance.