How to implement XML Digital Signature

[Norse]

I am creating a project in HTML where my project requirement is to implement XML Digital Signature and i don't have any idea about it and how to implement it, without it my project will be of no use, i had asked my friends about it but they also don't have much more idea about it. Any help would be very helpful for me and i would be great if you first explain me what is digital signature

[PARRISH]

Digital signature is a value computed with cryptographic algorithm and it is added to data in such a way that any person who is receiving it can use the signature to verify the data origin and integrity, nowadays most of the people use digital signature if they are sending some important on email. For example whenever you get bank statement on email it has digital signature in it.

[Shell]

Definitely i will help you out with this in the below code you can see that it is being indented and formatted for readability and at the same time note that Signature element is being inserted inside the content that is being use for making an enveloped signature

<?xml version="1.0" encoding="UTF-8"?>
<PurchaseOrder>
 <Item number="130046593231">
  <Description>Video Game1</Description>
  <amt>10.29</amt>
 </Item>
 <Buyer id="8492340">
  <Name>Your Name</Name>
  <Address>
   <Street>Street Name</Street>
   <Town>City Name</Town>
   <State>State Name</State>
   <Country>Country Name</Country>
   <PostalCode>Postal code </PostalCode>
  </Address>
 </Buyer>
 <Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
  <SignedInfo>
   <CanonicalizationMethod
    Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
   <SignatureMethod
    Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
   <Reference URI="">
    <Transforms>
     <Transform
      Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/>
    </Transforms>
    <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
    <DigestValue>tVicGh6V+8cHbVYFIU91o5+L3OQ=</DigestValue>
   </Reference>
  </SignedInfo>
  <SignatureValue>
   dJDHiGQMaKN8iPuWApAL57eVnxz2BQtyujwfPSgE7HyKoxYtoRB97ocxZ
   8ZU440wHtE39ZwRGIjvwor3WfURxnIgnI1CChMXXwoGpHH//Zc0z4ejaz
   DuCNEq4Mm4OUVTiEVuwcWAOMkfDHaM82awYQiOGcwMbZe38UX0oPJ2DOE=
  </SignatureValue>
  <KeyInfo>
   <X509Data>
    <X509SubjectName>
     CN=My Name,O=Test Certificates Inc.,C=US
    </X509SubjectName>
    <X509Certificate>
     MIIB9zCCAWCgAwIBAgIERZwdkzANBgkqhkiG9w0BAQUFADBAMQswCQYD
     VQQGEwJVUzEfMB0GA1UEChMWVGVzdCBDZXJ0aWZpY2F0ZXMgSW5jLjEQ
     MA4GA1UEAxMHTXkgTmFtZTAeFw0wNzAxMDMyMTE4MTFaFw0zMTA4MjUy
     ...
    </X509Certificate>
   </X509Data>
  </KeyInfo>
 </Signature>
</PurchaseOrder>

[Norse]

Thank you for providing example but it would be great if you can example me SignatureMethod, Reference, and Canonicalized SignedInfo

[Shell]

In my example SignatureMethod is being used to generate the signature, in my example i had used PKCS#1 RSA-SHA1 algorithm which is being described in RFC 2437 and one or more Reference elements identify the data that is signed. Each Reference element identifies the data by way of a URI and canonicalized SignedInfo is the element which is being used before it is being signed, this is useful for debugging canonicalization and signature verification failures.