/* TEMPLATE GENERATED TESTCASE FILE
Filename: CWE113_HTTP_Response_Splitting__getQueryString_Servlet_addHeaderServlet_45.java
Label Definition File: CWE113_HTTP_Response_Splitting.label.xml
Template File: sources-sinks-45.tmpl.java
*/
/*
 * @description
 * CWE: 113 HTTP Response Splitting
 * BadSource: getQueryString_Servlet Parse id param out of the URL query string (without using getParameter())
 * GoodSource: A hardcoded string
 * Sinks: addHeaderServlet
 *    GoodSink: URLEncode input
 *    BadSink : querystring to addHeader()
 * Flow Variant: 45 Data flow: data passed as a private class member variable from one function to another in the same class
 *
 * */




import javax.servlet.http.*;

import java.util.StringTokenizer;

import java.net.URLEncoder;

public class CWE113_HTTP_Response_Splitting__getQueryString_Servlet_addHeaderServlet_45 extends AbstractTestCaseServlet
{
    private String dataBad;
    private String dataGoodG2B;
    private String dataGoodB2G;

    private void badSink(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data = dataBad;

        /* POTENTIAL FLAW: Input from file not verified */
        if (data != null)
        {
            response.addHeader("Location", "/author.jsp?lang=" + data);
        }

    }

    public void bad(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 */
                }
            }
        }

        dataBad = data;
        badSink(request, response);
    }

    public void good(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        goodG2B(request, response);
        goodB2G(request, response);
    }

    private void goodG2BSink(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data = dataGoodG2B;

        /* POTENTIAL FLAW: Input from file not verified */
        if (data != null)
        {
            response.addHeader("Location", "/author.jsp?lang=" + data);
        }

    }

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

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

        dataGoodG2B = data;
        goodG2BSink(request, response);
    }

    private void goodB2GSink(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data = dataGoodB2G;

        /* FIX: use URLEncoder.encode to hex-encode non-alphanumerics */
        if (data != null)
        {
            data = URLEncoder.encode(data, "UTF-8");
            response.addHeader("Location", "/author.jsp?lang=" + data);
        }

    }

    /* goodB2G() - use badsource and goodsink */
    private void goodB2G(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 */
                }
            }
        }

        dataGoodB2G = data;
        goodB2GSink(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);
    }
}
