ed25519.js

import fs from "fs";
import { Ed25519KeyIdentity, Ed25519PublicKey } from "@dfinity/identity";
import { Principal } from "@dfinity/principal";
import tweetnacl from "tweetnacl";

// ED25519 version 2
// Private key and public key are included
export const getIdentityFromPem = (pem) => {
  pem = pem
    .replace("-----BEGIN PRIVATE KEY-----", "")
    .replace("-----END PRIVATE KEY-----", "")
    .replace("\n", "")
    .trim();

  const raw = Buffer.from(pem, "base64")
    .toString("hex")
    .replace("3053020101300506032b657004220420", "")
    .replace("a123032100", "");

  // including private key (32 bytes before public key)
  // and public key (last 32 bytes)
  const key = new Uint8Array(Buffer.from(raw, "hex"));

  const identity = Ed25519KeyIdentity.fromSecretKey(key);

  // =============================== CONFIRM ===============================

  console.log("Principal:", identity.getPrincipal().toText());

  const pair = identity.getKeyPair();

  console.log("Private key:", Buffer.from(pair.secretKey).toString("hex"));

  console.log(
    "Public key:",
    Buffer.from(pair.publicKey.toRaw()).toString("hex")
  );

  console.log(
    "=================================================================="
  );

  const newPair = tweetnacl.sign.keyPair.fromSeed(key.slice(0, 32));

  console.log(
    "New private key:",
    Buffer.from(newPair.secretKey).toString("hex")
  );

  console.log(
    "New public key:",
    Buffer.from(newPair.publicKey).toString("hex")
  );

  console.log(
    "=================================================================="
  );

  const challenge = new Date().getTime().toString();
  console.log("Message to verify:", challenge);

  const message = new Uint8Array(Buffer.from(challenge, "utf-8"));
  const signature = tweetnacl.sign.detached(message, newPair.secretKey);
  console.log("Signature:", Buffer.from(signature).toString("hex"));

  const result = tweetnacl.sign.detached.verify(
    message,
    signature,
    newPair.publicKey
  );
  console.log("Verify signature:", result);
};

const pem = fs.readFileSync(process.env.PEM_PATH).toString();

getIdentityFromPem(pem);