<!--
Illustration of a Denial of Serivce Attack - Infinite loop in retrieval method
==============================================================================

This signature cannot be normally verified because there in an infinite loop in the retrieval method.
To verify it you need to instruct your security library to ignore the KeyInfo and verify with the HMAC key

HMAC password = sample
-->
<ns0:e0 xmlns:ns0="http://www.w3.org/ns0">
 <ns0:e1 xml:id="e1"> 
 </ns0:e1>   
 <dsig:Signature xmlns:dsig="http://www.w3.org/2000/09/xmldsig#">
  <dsig:SignedInfo>
   <dsig:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
   <dsig:SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#hmac-sha1"/>
   <dsig:Reference URI="#e1">
    <dsig:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
    <dsig:DigestValue>WEhA2IFCfmddBl7PG5k82cVKw+Q=</dsig:DigestValue>
   </dsig:Reference>
  </dsig:SignedInfo>
  <dsig:SignatureValue>ZMN43U7EV7mWIUOPp/CWTv9xXOg=</dsig:SignatureValue>
  <dsig:KeyInfo>
   <dsig:RetrievalMethod xml:id="r1" URI="#r1"/>
  </dsig:KeyInfo>
 </dsig:Signature>
</ns0:e0>