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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 * restricted charsets. */ public class Charsets 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 restrictedCharsets = Splitter.on('/').splitToList(request.getPathInfo()).get(2); switch (restrictedCharsets) { case "SpaceDoubleQuoteSlashEquals": if (containsChars(echoedParam, '=', '\\', '"', ' ')) { Responses.sendError(response, "Invalid param.", 400); return; } break; case "DoubleQuoteSinglequote": if (containsChars(echoedParam, '"', '\'')) { Responses.sendError(response, "Invalid param.", 400); return; } break; default: Responses.sendError(response, "Invalid charset.", 400); return; } Responses.sendXssed(response, Templates.replacePayload(template, echoedParam)); } private boolean containsChars(String echoedParam, Character... chars) { for (Character character : chars) { if (echoedParam.contains(character.toString())) { return true; } } return false; } }