Node.js

SII Chile - FRMT Signature Computation and Add to XML

See more XML Digital Signatures Examples

Compute the FRMT signature and add to the XML. This is the RSA signature of the SHA-1 digest of the "flattened" DD element. Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

    //  This example assumes the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    //  Also see:  Compute the FRMA Signature and Add to XML

    var xml = new chilkat.Xml();

    //  Load the unsigned XML that contains the following:

    //  <DTE version="1.0">
    //    <Documento ID="F60T33">
    //          <TED version="1.0">
    //              <DD>
    //  		...
    //                  <CAF version="1.0">
    //                      <DA>
    //  			...
    //                      </DA>
    //                      <FRMA algoritmo="SHA1withRSA">...</FRMA>
    //                  </CAF>
    //                  ...
    //              </DD>
    //              ... The FRMT will be added here in another example ...
    //          </TED>
    //    </Documento>
    //  </DTE>

    success = xml.LoadXmlFile("qa_data/xml_dsig/sii_cl/test_1.xml");
    if (success == false) {
        console.log("Failed to load initial XML file.");
        return;
    }

    //  Get a reference to the "DD" element
    // ddXml: Xml
    var ddXml = xml.FindChild("Documento|TED|DD");
    if (xml.LastMethodSuccess == false) {
        console.log("Failed to find DD element");
        return;
    }

    //   We need to get the "flattened" DD XML where:
    //     - No whitespace between elements.
    //     - The 5 pre-defined entities are converted.
    //     - The text is encoded in the ISO-8859-1 character set (Latin-1), 
    var sbFlattened = new chilkat.StringBuilder();
    ddXml.EmitCompact = true;
    ddXml.EmitXmlDecl = false;
    ddXml.GetXmlSb(sbFlattened);

    //  Compute the SHA-1 message digest of the iso-8859-1 byte representation, 
    //  and sign it with our RSA private key, getting the result in base64 format.

    var privKey = new chilkat.PrivateKey();
    success = privKey.LoadAnyFormatFile("qa_data/rsa/rsaPrivKey_pkcs8.pem","");
    if (success == false) {
        console.log(privKey.LastErrorText);
        return;
    }

    var rsa = new chilkat.Rsa();
    rsa.UsePrivateKey(privKey);

    rsa.EncodingMode = "base64";
    rsa.Charset = "iso-8859-1";
    var sig = rsa.SignStringENC(sbFlattened.GetAsString(),"sha1");

    //  Add the FRMT signature element to the XML.
    xml.UpdateChildContent("Documento|TED|FRMT",sig);
    xml.UpdateAttrAt("Documento|TED|FRMT",true,"algoritmo","SHA1withRSA");

    //  See what we have:
    xml.EmitCompact = false;
    xml.EmitXmlDecl = true;
    console.log(xml.GetXml());

}

chilkatExample();