Signature Validation

"proof": {

    "jws": "<encoded_signature>",

    "public_key_url": "<url_for_public_key>"

}

const fs = require('fs');

const axios = require('axios');

const jose = require('jose');

const { canonicalize } = require('json-canonicalize');

​

// Load the JSON data from the file

const report = JSON.parse(fs.readFileSync('identity_profile_report.json', 'utf8'));

​

// Extract the proof.jws value and the proof.public_key_url

const jwsToken = report.proof.jws;

const publicKeyUrl = report.proof.public_key_url;

​

// Set the proof.jws value to an empty string

report.proof.jws = "";

​

// Canonicalize the JSON data according to RFC 8785

const canonicalizedReport = canonicalize(report);

​

// Base64url encode the canonicalized JSON data

const encodedPayload = Buffer.from(canonicalizedReport, 'utf8').toString('base64url');

​

// Decode the JWS token

const [protectedHeader, , signature] = jwsToken.split('.');

​

// Fetch the public key from the proof.public_key_url

axios.get(publicKeyUrl)

  .then(async response => {

    const publicKeyJwk = response.data.keys[0];

​

    // Import the public key using jose.importJWK

    const key = await jose.importJWK(publicKeyJwk, 'EdDSA');

​

    // Construct the JWS object

    const jws = {

      protected: protectedHeader,

      payload: encodedPayload,

      signature: signature

    };

​

    // Verify the JWS signature using the flattenedVerify method

    try {

      await jose.flattenedVerify(jws, key, {

        algorithms: ['EdDSA']

      });

​

      console.log("Signature is valid.");

    } catch (err) {

      console.error("Signature verification failed:", err);

    }

  })

  .catch(err => {

    console.error("Failed to fetch public key:", err);

  });