passport-azure-ad/lib/sessionContentHandler.js

OIDC and Bearer Passport strategies for Azure Active Directory

/**
 * Copyright (c) Microsoft Corporation
 *  All Rights Reserved
 *  MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this
 * software and associated documentation files (the "Software"), to deal in the Software
 * without restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
 * OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
 * OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

'use restrict';

const aadutils = require('./aadutils');

/*
 * the handler for state/nonce/policy
 * @maxAmout          - the max amount of {state: x, nonce: x, policy: x, timeStamp: x} tuples you want to save in the session
 * @maxAge            - when a tuple in session expires in seconds
 */ 
function SessionContentHandler(maxAmount, maxAge) {
  if (!maxAmount || (typeof maxAmount !== 'number' || maxAmount <= 0 || maxAmount % 1 !== 0))
    throw new Error('SessionContentHandler: maxAmount must be a positive integer');
  if (!maxAge || (typeof maxAge !== 'number' || maxAge <= 0))
    throw new Error('SessionContentHandler: maxAge must be a positive number');
  this.maxAge = maxAge;  // seconds
  this.maxAmount = maxAmount;
}

SessionContentHandler.prototype.findAndDeleteTupleByState = function(req, sessionKey, stateToFind) {
  if (!req.session)
    throw new Error('OIDC strategy requires session support. Did you forget to use session middleware such as express-session?');

  // the array in session
  var array = req.session[sessionKey] && req.session[sessionKey]['content'];
  if (!array)
    array = [];

  // remove the expired tuples in array
  aadutils.processArray(array, this.maxAmount, this.maxAge);

  // find the tuple by state value
  var tuple = aadutils.findAndDeleteTupleByState(array, stateToFind);

  // clear empty array, and clear the session if there is nothing inside
  if (req.session[sessionKey] && array.length === 0)
    delete req.session[sessionKey]['content'];
  if (req.session[sessionKey] && Object.keys(req.session[sessionKey]).length === 0)
    delete req.session[sessionKey];

  return tuple;
};

SessionContentHandler.prototype.add = function(req, sessionKey, tupleToAdd) {
  if (!req.session)
    req.session = {};
  if (!req.session[sessionKey])
    req.session[sessionKey] = {};
  if (!req.session[sessionKey]['content'])
    req.session[sessionKey]['content'] = [];

  var array = req.session[sessionKey]['content'];
  aadutils.processArray(array, this.maxAmount-1, this.maxAge);

  array.push(tupleToAdd);
};

exports.SessionContentHandler = SessionContentHandler;