Digitally Sign Parts of a XML document

Question

I have an XML document having structure similar to the following

    
blaa
    blaa blaa         


        

Answer 1

You should be able to add an XPath-Transform to the Signature. It should look something like this:

       
         
         ...
         
       

I am not fluent in XPath, but it should be easy to formulate an XPath-expression that excludes the Footer-element. (But note that XPath is an optional part of XML-DSIG, so not all implementations may support it).

Alternatively, if you could restructure your document to be

  
blaa
  blaa blaa
  

or

  
    
blaa
    blaa blaa
  
  

you could handle it by using an Enveloped Signature Transform (first case) or by signing the signedEnvelope element (second case).