server/web/validated-message.js

   1 'use strict';
   2
   3 var env = require('gitter-web-env');
   4 var config = env.config;
   5 var crypto = require('crypto');
   6
   7 var secret = config.get('web:messageSecret');
   8
   9 function validate(unvalidatedMessage, check, defaultMessage) {
  10   if (!unvalidatedMessage || !check) {
  11     return defaultMessage;
  12   }
  13
  14   unvalidatedMessage = String(unvalidatedMessage);
  15   check = String(check);
  16   var p = check.split(':');
  17   if (p.length !== 2) {
  18     return defaultMessage;
  19   }
  20
  21   var checksum = p[0];
  22   var salt = p[1];
  23
  24   var calculatedCheck = crypto
  25     .createHash('md5')
  26     .update(secret + salt + unvalidatedMessage, 'utf8')
  27     .digest('base64');
  28
  29   if (calculatedCheck === checksum) {
  30     return unvalidatedMessage;
  31   }
  32
  33   return defaultMessage;
  34 }
  35
  36 function getCheck(message) {
  37   if (!message) return '';
  38
  39   var salt = crypto.randomBytes(6).toString('base64');
  40
  41   var check = crypto
  42     .createHash('md5')
  43     .update(secret + salt + message, 'utf8')
  44     .digest('base64');
  45
  46   return check + ':' + salt;
  47 }
  48
  49 module.exports = {
  50   validate: validate,
  51   getCheck: getCheck
  52 };