/* TEMPLATE GENERATED TESTCASE FILE
Filename: CWE80_XSS__CWE182_Servlet_getQueryString_Servlet_42.java
Label Definition File: CWE80_XSS__CWE182_Servlet.label.xml
Template File: sources-sink-42.tmpl.java
*/
/*
 * @description
 * CWE: 80 Cross Site Scripting (XSS)
 * BadSource: getQueryString_Servlet Parse id param out of the URL query string (without using getParameter())
 * GoodSource: A hardcoded string
 * BadSink:  Display of data in web page after using replaceAll() to remove script tags, which will still allow XSS (CWE 182: Collapse of Data into Unsafe Value)
 * Flow Variant: 42 Data flow: data returned from one method to another in the same class
 *
 * */




import javax.servlet.http.*;

import java.util.StringTokenizer;

public class CWE80_XSS__CWE182_Servlet_getQueryString_Servlet_42 extends AbstractTestCaseServlet
{
    private String badSource(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data;

        data = ""; /* initialize data in case id is not in query string */

        /* POTENTIAL FLAW: Parse id param out of the URL querystring (without using getParameter()) */
        {
            StringTokenizer tokenizer = new StringTokenizer(request.getQueryString(), "&");
            while (tokenizer.hasMoreTokens())
            {
                String token = tokenizer.nextToken(); /* a token will be like "id=foo" */
                if(token.startsWith("id=")) /* check if we have the "id" parameter" */
                {
                    data = token.substring(3); /* set data to "foo" */
                    break; /* exit while loop */
                }
            }
        }

        return data;
    }

    /* use badsource and badsink */
    public void bad(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data = badSource(request, response);

        if (data != null)
        {
            /* POTENTIAL FLAW: Display of data in web page after using replaceAll() to remove script tags, which will still allow XSS with strings like <scr<script>ipt> (CWE 182: Collapse of Data into Unsafe Value) */
            response.getWriter().println("<br>bad(): data = " + data.replaceAll("(<script>)", ""));
        }

    }

    private String goodG2BSource(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data;

        /* FIX: Use a hardcoded string */
        data = "foo";

        return data;
    }

    /* goodG2B() - use goodsource and badsink */
    private void goodG2B(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data = goodG2BSource(request, response);

        if (data != null)
        {
            /* POTENTIAL FLAW: Display of data in web page after using replaceAll() to remove script tags, which will still allow XSS with strings like <scr<script>ipt> (CWE 182: Collapse of Data into Unsafe Value) */
            response.getWriter().println("<br>bad(): data = " + data.replaceAll("(<script>)", ""));
        }

    }

    public void good(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        goodG2B(request, response);
    }

    /* Below is the main(). It is only used when building this testcase on
     * its own for testing or for building a binary to use in testing binary
     * analysis tools. It is not used when compiling all the testcases as one
     * application, which is how source code analysis tools are tested.
     */
    public static void main(String[] args) throws ClassNotFoundException,
           InstantiationException, IllegalAccessException
    {
        mainFromParent(args);
    }

}
