Add token generation

dist/lib/otp.js

@@ -0,0 +1,55 @@
+"use strict";
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+const base32_1 = __importDefault(require("./base32"));
+const crypto_1 = require("crypto");
+class OTP {
+    constructor(seed = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXTZabcdefghiklmnopqrstuvwxyz!@#$-') {
+        this.seed = seed;
+    }
+    validateHotp(token, secret, counter) {
+        const counterInt = parseInt(counter, 10) || 0;
+        if (!secret || !token || token.length !== 6 || isNaN(parseInt(token, 10)))
+            return false;
+        return this._computeHotp(secret, counterInt) === token;
+    }
+    validateTotp(token, secret) {
+        return this.validateHotp(token, secret, Math.floor(Date.now() / 30 / 1000));
+    }
+    generateKey(name = 'Secret Key', issuer = null, hotp = false) {
+        const bytes = crypto_1.randomBytes(32);
+        const string = Array(32)
+            .fill(i => this.seed[Math.floor(bytes[i] / 255.0 * (this.seed.length - 1))])
+            .map((f, i) => f(i))
+            .join('');
+        const key = {
+            raw: string,
+            base32: base32_1.default.encode(string)
+        };
+        return Object.defineProperty(key, 'url', {
+            value: 'google_url',
+            writable: false,
+            get: () => `otpauth://${hotp ? 'h' : 't'}otp/${name}?secret=${key.base32}${issuer ? `&issuer=${issuer}` : ''}`
+        });
+    }
+    _computeHotp(secret, counter) {
+        secret = base32_1.default.decode(secret);
+        let tmp = counter;
+        const chunks = Buffer.alloc(8);
+        for (let i = 0; i < 8; i++) {
+            chunks[7 - i] = tmp & 0xff;
+            tmp = tmp >> 8;
+        }
+        const digest = crypto_1.createHmac('sha1', secret).update(chunks).digest();
+        const offset = digest[digest.length - 1] & 0xf;
+        let code = (digest[offset] & 0x7f) << 24 |
+            (digest[offset + 1] & 0xff) << 16 |
+            (digest[offset + 2] & 0xff) << 8 |
+            (digest[offset + 3] & 0xff);
+        code = new Array(7).join('0') + code.toString(10);
+        return code.substr(-6);
+    }
+}
+exports.default = OTP;