(CkPython) SAML Signature Validation

See more XML Digital Signatures Examples

A SAML Signature is an XML Digital Signature (XMLDSig) just like any other XML digital signature. It can be verified by using Chilkat' XmlDSig class, as shown in this example.

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install with pip
pip3 install chilkat
or download... Python Module for Windows, MacOS, Linux, Alpine Linux

import chilkat

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

dsig = chilkat.CkXmlDSig()
success = dsig.LoadSignature("XML xml signature goes here...")

# A sample SAML signature is shown below..

numSignatures = dsig.get_NumSignatures()
i = 0
while i < numSignatures :
    dsig.put_Selector(i)

    bVerifyRefDigests = False
    bSignatureVerified = dsig.VerifySignature(bVerifyRefDigests)
    if (bSignatureVerified == True):
        print("Signature " + str(i + 1) + " verified")
    else:
        print("Signature " + str(i + 1) + " invalid")

    # Check each of the reference digests separately..
    numRefDigests = dsig.get_NumReferences()
    j = 0
    while j < numRefDigests :
        bDigestVerified = dsig.VerifyReferenceDigest(j)
        print("reference digest " + str(j + 1) + " verified = " + str(bDigestVerified))
        if (bDigestVerified == False):
            print("    reference digest fail reason: " + str(dsig.get_RefFailReason()))

        j = j + 1

    i = i + 1

# --------------------------------------
# Here is a sample SAML XML Signature
# 
# 
# <?xml version="1.0" encoding="UTF-8"?>
# <saml2p:Response xmlns:saml2p="urn:oasis:names:tc:SAML:2.0:protocol" ID="abc123" Version="2.0" IssueInstant="2022-04-01T12:34:56Z" Destination="https://sp.example.com/sso">
#   <saml2:Issuer xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion">https://idp.example.com</saml2:Issuer>
#   <saml2p:Status>
#     <saml2p:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Success"/>
#   </saml2p:Status>
#   <saml2:Assertion xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion" ID="def456" IssueInstant="2022-04-01T12:34:56Z" Version="2.0">
#     <saml2:Issuer>https://idp.example.com</saml2:Issuer>
#     <saml2:Subject>
#       <saml2:NameID Format="urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress">user@example.com</saml2:NameID>
#     </saml2:Subject>
#     <saml2:Conditions NotBefore="2022-04-01T12:34:56Z" NotOnOrAfter="2022-04-01T13:34:56Z"/>
#     <saml2:AuthnStatement AuthnInstant="2022-04-01T12:34:56Z">
#       <saml2:AuthnContext>
#         <saml2:AuthnContextClassRef>urn:oasis:names:tc:SAML:2.0:ac:classes:Password</saml2:AuthnContextClassRef>
#       </saml2:AuthnContext>
#     </saml2:AuthnStatement>
#     <!-- Additional assertion content -->
#   </saml2:Assertion>
#   <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
#     <ds:SignedInfo>
#       <ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
#       <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>
#       <ds:Reference URI="#abc123">
#         <ds:Transforms>
#           <ds:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/>
#           <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
#         </ds:Transforms>
#         <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
#         <ds:DigestValue>q7Zj1w+...+pCsjw=</ds:DigestValue>
#       </ds:Reference>
#       <!-- Additional references if present -->
#     </ds:SignedInfo>
#     <ds:SignatureValue>
#       NjIzOWE5ZjA2M2M1...NzUwNzUwNzUwNzUwNzU=
#     </ds:SignatureValue>
#     <ds:KeyInfo>
#       <ds:X509Data>
#         <ds:X509Certificate>
#           MIIDgzCCAmugAwIBAg...AgADAA==
#         </ds:X509Certificate>
#       </ds:X509Data>
#     </ds:KeyInfo>
#   </ds:Signature>
# </saml2p:Response>