(Chilkat2-Python) Verify SOAP XML using a wsse:SecurityTokenReference

This example verifies a SOAP XML Digital Signature where the KeyInfo in the XML Signature is a wsse:SecurityTokenReference to the X.509 certificate embedded elsewhere in the SOAP XML.

Chilkat2 Python Downloads install with pip pip3 install chilkat2 or download... Python Module for Windows, Linux, Alpine Linux, MacOS, Solaris

import sys
import chilkat2

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

# The SOAP XML with digital signature verified in this example is available at 
# https://www.chilkatsoft.com/exampleData/signedSoapBinarySecurityToken.xml

signedSoapXmlUrl = "https://www.chilkatsoft.com/exampleData/signedSoapBinarySecurityToken.xml"

# First, let's get the signed SOAP XML..
http = chilkat2.Http()
sbXml = chilkat2.StringBuilder()
success = http.QuickGetSb(signedSoapXmlUrl,sbXml)
if (success != True):
    print(http.LastErrorText)
    sys.exit()

# The signed XML downloaded from the above URL contains the following.
# Note: Everything we need to verify the signature is already available within the signed XML.
# The KeyInfo part of the Signature contains a reference to the wsse:BinarySecurityToken
# For clarity, here is the KeyInfo section extracted from the Signature below:
# 
# <ds:KeyInfo><wsse:SecurityTokenReference><wsse:Reference URI="#x509cert00" ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509" /></wsse:SecurityTokenReference></ds:KeyInfo>
# 
# Chilkat has the capability to automatically follow the SecurityTokenReference.  It will automatically locate the 
# certificate contained in the wsse:BinarySecurityToken element (in this case identified by Id="x509cert00"), 
# automatically extracts the public key from the base64 X.509 certificate, and uses it to verify the signature.

# <?xml version="1.0" encoding="UTF8"?>
# <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
# <SOAP-ENV:Header>
#  <wsse:Security xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
#                 xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
#                 xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
#                 xmlns:xenc="http://www.w3.org/2001/04/xmlenc#" SOAP-ENV:mustUnderstand="1">
#  <wsse:BinarySecurityToken
#                EncodingType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0#Base64Binary"
#                ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509"
#                wsu:Id="x509cert00">MIIDg...</wsse:BinarySecurityToken>
#  <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#"><InclusiveNamespaces xmlns="http://www.w3.org/2001/10/xml-exc-c14n#" PrefixList="wsse SOAP-ENV"/></ds:CanonicalizationMethod><ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/><ds:Reference URI="#TheBody"><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/><ds:DigestValue>VhsSnaEAFsY0OYegKQh99v9csXg=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>Ynp3H4rtzpXIh4TaVxkpEkS1bMCCu672aeCzUOzheNNfnpmLsCZz3+zQjMBbchPggCayC5ihpEdhRe3XvPXjPXXAgxDP4mic091QPmjHlmUcu8yqRKfxnPtD35nqaxDtCYw+jGIzj+ch094vA4RPCfY8JQnb1mpy1ZjjsMW8741CIh1epbsd/0bZt6tfINUQ37seg07yvLbCJZ/Zf+h8FlFryQk6lHTTeZl/GfQ9NlDBcShby3x8Hc1KwW++zFqEA7G783R9AYPYn3fWTOBhYk5gkgFc+HaPRLR/L0Bp7ZPbmOR/iZQ+HK4W672tTdN/R2GdN7/deV7QTp2DYK1Z8w==</ds:SignatureValue><ds:KeyInfo><wsse:SecurityTokenReference><wsse:Reference URI="#x509cert00" ValueType="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-x509-token-profile-1.0#X509" /></wsse:SecurityTokenReference></ds:KeyInfo></ds:Signature></wsse:Security>
# </SOAP-ENV:Header>
# <SOAP-ENV:Body xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="TheBody">
#  <getVersion xmlns="http://msgsec.wssecfvt.ws.ibm.com"/>
# </SOAP-ENV:Body>
# </SOAP-ENV:Envelope>
# 

# To verify this signature, we simply load and verify:
verifier = chilkat2.XmlDSig()
success = verifier.LoadSignatureSb(sbXml)
if (success != True):
    print(verifier.LastErrorText)
    sys.exit()

bVerified = verifier.VerifySignature(True)
if (bVerified != True):
    print(verifier.LastErrorText)
    sys.exit()

print("Signature verified!")