ethers.js/admin/config.js
2020-02-12 17:18:43 -05:00

117 lines
3.2 KiB
JavaScript

"use strict";
const fs = require("fs");
const os = require("os");
const resolve = require("path").resolve;
const AES = require("aes-js");
const scrypt = require("scrypt-js");
const { prompt } = require("../packages/cli");
const randomBytes = require("../packages/random").randomBytes;
const computeHmac = require("../packages/sha2").computeHmac;
const colorify = require("./log").colorify;
function getScrypt(message, password, salt) {
let progressBar = prompt.getProgressBar(message);
return scrypt.scrypt(Buffer.from(password), Buffer.from(salt), (1 << 17), 8, 1, 64, progressBar);
}
function Config(filename) {
this.salt = null;
this.dkey = null;
this.values = { };
this.filename = filename;
}
Config.prototype.load = async function() {
if (this.dkey) { return; }
let data = null;
if (fs.existsSync(this.filename)) {
data = JSON.parse(fs.readFileSync(this.filename));
} else {
data = {
salt: Buffer.from(randomBytes(32)).toString("hex")
};
}
this.salt = data.salt;
const password = await prompt.getPassword(colorify("Password (config-store): ", "bold"));
this.dkey = await getScrypt(colorify("Unlocking config", "bold"), password, this.salt);
if (data.ciphertext) {
const ciphertext = Buffer.from(data.ciphertext, "base64");
const iv = Buffer.from(data.iv, "base64");
const aes = new AES.ModeOfOperation.ctr(this.dkey.slice(0, 32), new AES.Counter(iv));
const plaintext = aes.decrypt(ciphertext);
const hmac = computeHmac("sha512", this.dkey.slice(32, 64), plaintext);
if (hmac !== data.hmac) {
throw new Error("wrong password");
}
this.values = JSON.parse(Buffer.from(plaintext).toString());
}
};
Config.prototype.keys = async function() {
await this.load();
return Object.keys(this.values);
}
Config.prototype.save = function() {
this.values._junk = Buffer.from(randomBytes(16 + parseInt(Math.random() * 48))).toString("base64")
const plaintext = Buffer.from(JSON.stringify(this.values));
const iv = Buffer.from(randomBytes(16));
const hmac = computeHmac("sha512", this.dkey.slice(32, 64), plaintext);
const aes = new AES.ModeOfOperation.ctr(this.dkey.slice(0, 32), new AES.Counter(iv));
const ciphertext = Buffer.from(aes.encrypt(plaintext));
const data = {
ciphertext: ciphertext.toString("base64"),
iv: iv.toString("base64"),
salt: this.salt,
hmac: hmac
};
fs.writeFileSync(this.filename, JSON.stringify(data, null, 2));
}
Config.prototype.get = async function(key) {
await this.load();
return this.values[key];
};
Config.prototype.set = async function(key, value) {
await this.load();
this.values[key] = value;
this.save();
};
Config.prototype.lock = function() {
this.salt = this.dkey = null;
}
const config = new Config(resolve(os.homedir(), ".ethers-dist"));
module.exports = {
get: function(key) {
return config.get(key);
},
set: function(key, value) {
config.set(key, value);
},
keys: function() {
return config.keys();
},
lock: function() {
config.lock();
}
}