(CkPython) Examine KeyInfo Certificate in XML Signature

This example loads signed XML and gets the signing certificate, assuming the certificate is contained in X509Certificate within the KeyInfo.

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import sys
import chilkat

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

dsig = chilkat.CkXmlDSig()
sbXml = chilkat.CkStringBuilder()

success = sbXml.LoadFile("c:/aaworkarea/elias/3/face_f09006808443a699d1b.xml","utf-8")
if (success != True):
    print("Failed to load XML file.")
    sys.exit()

success = dsig.LoadSignatureSb(sbXml)
if (success != True):
    print(dsig.lastErrorText())
    sys.exit()

# Get the KeyInfo XML.
# xmlKeyInfo is a CkXml
xmlKeyInfo = dsig.GetKeyInfo()
if (dsig.get_LastMethodSuccess() != True):
    print(dsig.lastErrorText())
    sys.exit()

print(xmlKeyInfo.getXml())
print("----")

# Assuming the X509Certificate is in the KeyInfo, it will look like this:

#   <ds:KeyInfo Id="...">
#     <ds:KeyValue>
#     ...  
#     <ds:X509Data>
#       <ds:X509Certificate>MIIHAz...</ds:X509Certificate>
#     </ds:X509Data>
#   </ds:KeyInfo>
certBase64 = xmlKeyInfo.getChildContent("*:X509Data|*:X509Certificate")
if (xmlKeyInfo.get_LastMethodSuccess() != True):
    print("No X509Certificate found in the KeyInfo.")
    sys.exit()

# Load a certificate object w/ the base64.
cert = chilkat.CkCert()
success = cert.LoadFromBase64(certBase64)
if (success != True):
    print(cert.lastErrorText())
    sys.exit()

# Examine the cert..
print("SubjectDN: " + cert.subjectDN())
print("IssuerDN: " + cert.issuerDN())
print("SerialNumber as Decimal: " + cert.serialDecimal())