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Rust Requires Chilkat v11.0.0+

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.

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Rust

// 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

let xml = chilkat::Xml::new();

// 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>

if xml.load_xml_file("qa_data/xml_dsig/sii_cl/test_1.xml").is_err() {
    println!("Failed to load initial XML file.");
    return;
}

// Get a reference to the "DD" element
let Ok(dd_xml) = xml.find_child("Documento|TED|DD") else {
    println!("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), 
let sb_flattened = chilkat::StringBuilder::new();
dd_xml.set_emit_compact(true);
dd_xml.set_emit_xml_decl(false);
let _ = dd_xml.get_xml_sb(&sb_flattened);

// 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.

let priv_key = chilkat::PrivateKey::new();
if priv_key.load_any_format_file("qa_data/rsa/rsaPrivKey_pkcs8.pem", "").is_err() {
    println!("{}", priv_key.last_error_text());
    return;
}

let rsa = chilkat::Rsa::new();
let _ = rsa.use_private_key(&priv_key);

rsa.set_encoding_mode("base64");
rsa.set_charset("iso-8859-1");
let sig = rsa.sign_string_enc(&sb_flattened.get_as_string().unwrap_or_default(), "sha1").unwrap_or_default();

// Add the FRMT signature element to the XML.
xml.update_child_content("Documento|TED|FRMT", &sig);
let _ = xml.update_attr_at("Documento|TED|FRMT", true, "algoritmo", "SHA1withRSA");

// See what we have:
xml.set_emit_compact(false);
xml.set_emit_xml_decl(true);
println!("{}", xml.get_xml().unwrap_or_default());