e2ee-diffiehellman.js

"use strict";

// Dependencies
const sAES256 = require("simple-aes-256")
const crypto = require("crypto")

// Variables
const message = "The First Decree"

// Functions
const sAES256E = (string, key)=>{return sAES256.encrypt(key, string).toString("hex")}
const sAES256D = (string, key)=>{return sAES256.decrypt(key, Buffer.from(string, "hex")).toString("utf8")}

// Main
//* Server
const server = crypto.createDiffieHellman(2048)
const serverPK = server.generateKeys()

//* Client
const client = crypto.createDiffieHellman(server.getPrime(), server.getGenerator()) // Prime and Generator is encoded to something and passed to client from server.
const clientPK = client.generateKeys()

//* Client-End
const serverSecret = client.computeSecret(serverPK)

//* Server-End
const clientSecret = server.computeSecret(clientPK)

//* End
const encrypted = sAES256E(message, serverSecret.toString("hex"))
const decrypted = sAES256D(encrypted, clientSecret.toString("hex"))

console.log("Server Key:", serverSecret.toString("hex"))
console.log("Client Key:", clientSecret.toString("hex"))
console.log("Encrypted:", encrypted)
console.log("Decrypted:", decrypted)