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/* *Copyright 2014 Google Inc. All rights reserved. * * 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.google.testing.security.firingrange.tests.reflected; import com.google.common.base.Splitter; import com.google.common.base.Strings; import com.google.testing.security.firingrange.utils.Responses; import com.google.testing.security.firingrange.utils.Templates; import java.io.IOException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * Handles reflected XSS on parameters on any method, but applies filtering based on * substrings. */ public class Substrings extends HttpServlet { private static final String ECHOED_PARAM = "q"; @Override public void service(HttpServletRequest request, HttpServletResponse response) throws IOException { String echoedParam = Strings.nullToEmpty(request.getParameter(ECHOED_PARAM)); String template = Templates.getTemplate(request, getClass()); String restrictionModifier = Splitter.on('/').splitToList(request.getPathInfo()).get(2); String restrictedString = Splitter.on('/').splitToList(request.getPathInfo()).get(3); switch (restrictionModifier) { case "caseSensitive": if (containsSubstrings(echoedParam, restrictedString)) { Responses.sendError(response, "Invalid param.", 400); return; } break; case "caseInsensitive": if (containsSubstrings(echoedParam.toLowerCase(), restrictedString.toLowerCase())) { Responses.sendError(response, "Invalid param.", 400); return; } break; default: Responses.sendError(response, "Invalid restriction.", 400); return; } Responses.sendXssed(response, Templates.replacePayload(template, echoedParam)); } private boolean containsSubstrings(String echoedParam, String... strings) { for (String substring : strings) { if (echoedParam.contains(substring)) { return true; } } return false; } }