[BUG] EnvelopedSignature transform fails when signature is nested in child element #525
Description
Description
The library produces invalid signatures when using the enveloped-signature transform with nested signature placement using location.
Reproduction
import { SignedXml } from "../src/index";
import { generateKeyPairSync } from "crypto";
import { expect } from "chai";
import * as xpath from "xpath";
import * as xmldom from "@xmldom/xmldom";
import * as isDomNode from "@xmldom/is-dom-node";
describe("EnvelopedSignature with nested signature location", function () {
it("should verify signature when signature is nested in a child element", function () {
// Generate keys
const { privateKey, publicKey } = generateKeyPairSync("rsa", {
modulusLength: 2048,
publicKeyEncoding: { type: "spki", format: "pem" },
privateKeyEncoding: { type: "pkcs8", format: "pem" },
});
const xml = "<root><SignatureInformation/></root>";
// Sign
const sig = new SignedXml();
sig.privateKey = privateKey;
sig.addReference({
xpath: "/*",
transforms: [
"http://www.w3.org/2000/09/xmldsig#enveloped-signature",
"http://www.w3.org/2001/10/xml-exc-c14n#",
],
digestAlgorithm: "http://www.w3.org/2001/04/xmlenc#sha256",
});
sig.canonicalizationAlgorithm = "http://www.w3.org/2001/10/xml-exc-c14n#";
sig.signatureAlgorithm = "http://www.w3.org/2001/04/xmldsig-more#rsa-sha256";
// Place signature inside SignatureInformation (not as direct child of root)
sig.computeSignature(xml, {
location: {
action: "append",
reference: "//*[local-name()='SignatureInformation']",
},
});
const signedXml = sig.getSignedXml();
// Verify
const doc = new xmldom.DOMParser().parseFromString(signedXml);
const signatureNode = xpath.select1(
"//*[local-name(.)='Signature' and namespace-uri(.)='http://www.w3.org/2000/09/xmldsig#']",
doc,
);
isDomNode.assertIsNodeLike(signatureNode);
const verifier = new SignedXml();
verifier.publicCert = publicKey;
verifier.loadSignature(signatureNode);
const result = verifier.checkSignature(signedXml);
expect(result, "Signature verification should succeed").to.be.true;
});
});