X509CrlToXmlDoc (String function)

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Convert BER encoded X.509 CRL to XML (String class)

[Introduced in Sirius Mods 8.0]

X509 is a general authentication framework that establishes standard formats for for public-key certificates, certificate revocation list (CRLs), and more. X509CrlToXmlDoc converts a string (Longstring) that contains a CRL to an XmlDoc. DER (Distinguished Encoding Rules), a subset of BER (Basic Encoding Rules, provide a way to uniquely encode an Abstract Syntax Notation One (ASN.1) type value as a string of eight-bit octets.

Syntax

%doc = string:X509CrlToXmlDoc Throws InvalidBerData

Syntax terms

%doc An XmlDoc object variable to contain the decoded value of the method object, string.
string A DER encoded string that contains the contents of a CRL (Certificate Revocation List).

Usage notes

  • Prior to version 7.7 of Model 204, input to this method that created any element in the result XmlDoc with a text child whose length exceeded 650 characters produced an error. As of version 7.7, the lengths of the created text nodes are not restricted.
  • X509CrlToXmlDoc is very similar to DerToXmlDoc, except that X509CrlToXmlDoc understands the semantics of the CRL tags, so it provides more meaningful XML element names. Contrast the DerToXmlDoc example with the X509CrlToXmlDoc example, below.
  • X509CrlToXmlDoc is a complete implementation of the PKCS standards for CRLs.
  • Janus Web Server is not equipped to use the XmlDoc CRLs automatically; you have to process them yourself. Probably, for efficiency, you want to get the CRL at startup time, then store it somewhere easy to get at (a global NamedArraylist, for example, or a file, depending on how many certificates are in the list.
  • Currently, no method is available to produce a DER stream from an XmlDoc nor to validate the signature on a CRL.

Examples

  1. The PemToString example loads a Longstring with the contents of the base64 encoded CRL (Certificate Revocation List). If that Longstring is %ls below, the following statement converts that string to the XmlDoc whose contents are printed thereafter:

    %ls:x509CrlToXmlDoc:print

    The result is shown in part below:

    <CertificateList> <tbsCertList> <signature> <algorithm name="md5WithRSAEncryption"> 1.2.840.113549.1.1.4 </algorithm> <parameters/> </signature> <issuer> <RelativeDistinguishedName> <countryName>AU</countryName> </RelativeDistinguishedName> <RelativeDistinguishedName> <stateOrProvinceName type="PrintableString"> QLD </stateOrProvinceName> </RelativeDistinguishedName> ... </issuer> <thisUpdate type="UTCTime"> 20010115162657.000Z </thisUpdate> <nextUpdate type="UTCTime"> 20010214162657.000Z </nextUpdate> <revokedCertificates> <revokedCertificate> <userCertificate>1</userCertificate> <revocationDate type="UTCTime"> 19951009233205.000Z </revocationDate> </revokedCertificate> <revokedCertificate> <userCertificate>3</userCertificate> <revocationDate type="UTCTime"> 19951201010000.000Z </revocationDate> </revokedCertificate> <revokedCertificate> <userCertificate>4660</userCertificate> <revocationDate type="UTCTime"> 20010115161947.000Z </revocationDate> </revokedCertificate> ... </revokedCertificates> </tbsCertList> ... </CertificateList>

  2. If you have a web port from which you can get a CRL, you might do something like this:

    %httprequest:url = %crlUrl %httpResponse = %httpRequest:Get %doc = %httpResponse:X509CrlToXmlDoc

    Note: Janus will not validate a signature on a CRL returned by a Get.

See also

String methods:

Stringlist methods:

System methods:

Socket methods:

Background information: