Create a Signature Based on a Template

CreaSign enables you to create a signature based on a template file. The template file should contain the following:

one or more nodes that should be signed,
the <ds:Signature> node containing references to the nodes that should be signed.

The following is an example of a template XML file. It contains three orders and a template signature node with references to the second and the third node:

<orders>
  <order Id="first">
    <customer>
      <name>Karl the Great</name>
      <phone_number>123-342-353</phone_number>
    </customer>
    <item>
      <number>908784375</number>
      <description>royal crown</description>
      <price>123421</price>
    </item>
    <date_of_purchase>2002-10-23</date_of_purchase>
    <date_of_delivery>2002-11-03</date_of_delivery>
  </order>

  <order Id="second">
    <customer>
      <name>Karl the small</name>
      <phone_number>123-342-353</phone_number>
    </customer>
    <item>
      <number>3496875</number>
      <description>yellow hat</description>
      <price>12123</price>
    </item>
    <date_of_purchase>2002-10-27</date_of_purchase>
    <date_of_delivery>2002-11-07</date_of_delivery>
  </order>
  
      <!-- This is a signature template. CreaSign will calculate the signature based on the references provided here -->
	<ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#" Id="MySignature">
		<ds:SignedInfo>
			<ds:CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"></ds:CanonicalizationMethod>
			<ds:SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"></ds:SignatureMethod>
			<ds:Reference URI="#second">
				<ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"></ds:DigestMethod>
				<ds:DigestValue></ds:DigestValue>
			</ds:Reference>
			<ds:Reference URI="#third">
				<ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"></ds:DigestMethod>
				<ds:DigestValue></ds:DigestValue>				
			</ds:Reference>
		</ds:SignedInfo>		
	</ds:Signature>  
  
  <order Id="third">
    <customer>
      <name>Karl the strong</name>
      <phone_number>83245-1234</phone_number>
    </customer>
    <item>
      <number>123</number>
      <description>ten-gram weight</description>
      <price>992</price>
    </item>
    <date_of_purchase>2002-10-27</date_of_purchase>
    <date_of_delivery>2002-11-07</date_of_delivery>
  </order>
    
</orders>

To create a signature based on a template XML, follow these steps:

Load a template XML document.
Create a new XmlSignature object and attach it to the template node.
Call the CreateSignature method.

' The following certificate will be used for signing
signingCert="CERT_FIND_SUBJECT_STR=CREA_TESTUSER_1"

' Load a template xml from file. It already contains all the references
set doc=CreateObject("Msxml2.FreeThreadedDOMDocument.4.0")
doc.preserveWhiteSpace=true
doc.load "files\orders sign template.xml"

' Create a signature object
set cs = CreateObject("CreaSignClientIE.XmlSignature")

' Attach it to the existing signature node
cs.XmlNode=doc.selectSingleNode("//*[@Id='MySignature']")

' Create a signature
cs.CreateSignature signingCert,0

' Save the result to a file
saveTo="files/signedTemplate.xml"
if WScript.Arguments.Count>0 then saveTo=WScript.Arguments(0)
doc.save saveTo

WScript.Echo "Result saved to: " & saveTo

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