(AutoIt) Extract SignatureValue from Signed XML

See more XML Digital Signatures Examples

Demonstrates how to extract the signature value from signed XML.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

; 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>

Local $sFilePath = "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:
$oSb = ObjCreate("Chilkat.StringBuilder")
Local $bSuccess = $oSb.LoadFile($sFilePath,"utf-8")
If ($bSuccess = False) Then
    ConsoleWrite("Failed to load file." & @CRLF)
    Exit
EndIf

Local $sBase64Sig = $oSb.GetBetween("SignatureValue>","</")
ConsoleWrite("base64Sig = " & $sBase64Sig & @CRLF)

; -----------------------------------------------------------------------------------------
; 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..
$oXml = ObjCreate("Chilkat.Xml")
$bSuccess = $oXml.LoadXmlFile($sFilePath)
; Assume success..

$sBase64Sig = $oXml.GetChildContent("SOAP-ENV:Header|wsse:Security|ds:Signature|ds:SignatureValue")
ConsoleWrite("base64Sig = " & $sBase64Sig & @CRLF)

; -----------------------------------------------------------------------------------------
; Or perhaps you don't know where the signature is located in the XML.
; You can search for the tag..
Local $oXSigVal = $oXml.SearchForTag($oXml,"*:SignatureValue")
If ($oXml.LastMethodSuccess = True) Then
    ConsoleWrite("base64Sig = " & $oXSigVal.Content & @CRLF)

Else
    ConsoleWrite("No SignatureValue found." & @CRLF)
EndIf