refactored server to break out into node modules

server/token-utils.js

@@ -0,0 +1,39 @@
+const crypto = require('crypto');
+const conf = require('./conf.js');
+
+const encrypt = (obj) => {
+    let str = JSON.stringify(obj);
+    let iv = crypto.randomBytes(16);
+    let cipher = crypto.createCipheriv('aes256', conf.getTokenKey(), iv);
+    let ciphered = cipher.update(str, 'utf8', 'hex');
+    ciphered += cipher.final('hex');
+    return iv.toString('hex') + ':' + ciphered;
+}
+
+const decrypt = (ciphertext) => {
+    let components = ciphertext.split(':');
+    let iv_from_ciphertext = Buffer.from(components.shift(), 'hex');
+    let decipher = crypto.createDecipheriv('aes256', conf.getTokenKey(), iv_from_ciphertext);
+    let deciphered = decipher.update(components.join(':'), 'hex', 'utf8');
+    deciphered += decipher.final('utf8');
+    return JSON.parse(deciphered);
+}
+
+async function deriveKey(salt, pw){
+    return new Promise( (resolve, reject) => {
+        crypto.scrypt(pw, salt, 64, (err, key) => {
+            resolve(key.toString('hex'));
+        });
+    }); 
+}
+
+function createSalt(){
+    return crypto.randomBytes(16).toString('hex');
+}
+
+module.exports = { 
+    encrypt: encrypt, 
+    decrypt: decrypt, 
+    deriveKey: deriveKey,
+    createSalt: createSalt
+}