com.demandware.vulnapp.challenge.impl.CookieChallenge.java Source code

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Here is the source code for com.demandware.vulnapp.challenge.impl.CookieChallenge.java

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/*
 * Copyright 2016 Demandware Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.demandware.vulnapp.challenge.impl;

import javax.servlet.http.Cookie;

import org.apache.commons.codec.binary.Base64;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

import com.demandware.vulnapp.challenge.AbstractChallenge;
import com.demandware.vulnapp.servlet.DIVAServletRequestWrapper;
import com.demandware.vulnapp.util.Helpers;

/**
 * Cookie contains auth information, change the auth to grant access
 * 
 * @author Chris Smith
 *
 */
public class CookieChallenge extends AbstractChallenge {

    public static final String RED_HERRING = "red_herring";
    public static final String COOKIE_NAME = "challenge_access";
    public static final String ACCESS_KEY = "access_granted";
    private static final int MAX_AGE = 5 * 60; //5mins

    protected CookieChallenge(String name) {
        super(name);
    }

    public Boolean handleChallengeRequest(DIVAServletRequestWrapper req) {
        boolean grantsAccess = false;
        Cookie c = getChallengeCookie(req);
        if (c != null) {
            grantsAccess = doesCookieValueGrantAccess(c);
        }
        req.getResponse().addCookie(generateCookie());
        return grantsAccess;
    }

    private Cookie getChallengeCookie(DIVAServletRequestWrapper req) {
        Cookie[] cs = req.getCookies();
        Cookie cookie = null;
        if (cs != null) {
            for (Cookie c : cs) {
                if (c.getName().equals(COOKIE_NAME)) {
                    cookie = c;
                    break;
                }
            }
        }
        return cookie;
    }

    private boolean doesCookieValueGrantAccess(Cookie c) {
        boolean grant = false;
        String value = new String(Base64.decodeBase64(c.getValue()));
        try {
            JSONObject o = (JSONObject) new JSONParser().parse(value);
            grant = Helpers.isTruthy((String) o.get(ACCESS_KEY));
        } catch (ParseException e) {
            grant = false;
        }
        return grant;
    }

    @SuppressWarnings("unchecked")
    private Cookie generateCookie() {
        JSONObject o = new JSONObject();
        o.put(ACCESS_KEY, "false");
        String value = new String(Base64.encodeBase64(o.toJSONString().getBytes()));
        Cookie c = new Cookie(COOKIE_NAME, value);
        c.setMaxAge(MAX_AGE);
        c.setPath("/");
        return c;
    }

}