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Extract SignatureValue from Signed XML
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Demonstrates how to extract the signature value from signed XML.Chilkat B4X Downloads
Dim success As Boolean = False
' This example will work with the following signed XML, which as been reformatted for readability.
' <?xml version="1.0" encoding="utf-8"?>
' <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
' <SOAP-ENV:Header>
' <wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" SOAP-ENV:mustUnderstand="1">
' <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="#Body">
' <ds:Transforms>
' <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>OwgHPZNfDkXnZsjpfzXqAcT3RV3HzmTsEy2bP44FJ0M=</ds:DigestValue>
' </ds:Reference>
' </ds:SignedInfo>
' <ds:SignatureValue>C+7FWngU....DJFBcdg==</ds:SignatureValue>
' <ds:KeyInfo>
' <ds:KeyValue>
' <ds:RSAKeyValue>
' <ds:Modulus>sXeRhM55P13.....NAcibRw==</ds:Modulus>
' <ds:Exponent>AQAB</ds:Exponent>
' </ds:RSAKeyValue>
' </ds:KeyValue>
' </ds:KeyInfo>
' </ds:Signature>
' </wsse:Security>
' </SOAP-ENV:Header>
' <SOAP-ENV:Body xmlns:SOAP-SEC="http://schemas.xmlsoap.org/soap/security/2000-12" SOAP-SEC:id="Body">
' <z:FooBar xmlns:z="http://example.com"/>
' </SOAP-ENV:Body>
' </SOAP-ENV:Envelope>
' -----------------------------------------------------------------------------------------
' There are a number of ways we can get the contents of the <ds:SignatureValue>...</ds:SignatureValue>
Dim filePath As String = "qa_data/xml_dsig_testing/sample_to_show_how_to_extract_sig.xml"
' If you know there will only be a single SignatureValue in the XML, you don't need to parse XML.
' Just do quick and simple string search..
' For example:
Dim sb As ChilkatStringBuilder
sb.Initialize
success = sb.LoadFile(filePath, "utf-8")
If success = False Then
Log("Failed to load file.")
Return
End If
Dim base64Sig As String = sb.GetBetween("SignatureValue>", "</")
Log("base64Sig = " & base64Sig)
' -----------------------------------------------------------------------------------------
' If the XML might contain multiple signatures, but the signatures will always be located in the
' same place, then you can (beforehand) copy a sample signed XML into Chilkat's online tool
' at Generate Parsing Code from XML
' to get the path to the SignatureValue. For example, the line of code generated for the SignatureValue
' for the above XML is:
' string ds_SignatureValue = xml.GetChildContent("SOAP-ENV:Header|wsse:Security|ds:Signature|ds:SignatureValue");
' So you can simply use that path..
Dim xml As ChilkatXml
xml.Initialize
success = xml.LoadXmlFile(filePath)
' Assume success..
base64Sig = xml.GetChildContent("SOAP-ENV:Header|wsse:Security|ds:Signature|ds:SignatureValue")
Log("base64Sig = " & base64Sig)
' -----------------------------------------------------------------------------------------
' Or perhaps you don't know where the signature is located in the XML.
' You can search for the tag..
Dim xSigVal As ChilkatXml = xml.SearchForTag(xml, "*:SignatureValue")
If xml.LastMethodSuccess = True Then
Log("base64Sig = " & xSigVal.Content)
Else
Log("No SignatureValue found.")
End If