/* TEMPLATE GENERATED TESTCASE FILE
Filename: CWE113_HTTP_Response_Splitting__getQueryString_Servlet_setHeaderServlet_16.java
Label Definition File: CWE113_HTTP_Response_Splitting.label.xml
Template File: sources-sinks-16.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: setHeaderServlet
*    GoodSink: URLEncode input
*    BadSink : querystring to setHeader()
* Flow Variant: 16 Control flow: while(true)
*
* */




import javax.servlet.http.*;

import java.util.StringTokenizer;

import java.net.URLEncoder;

public class CWE113_HTTP_Response_Splitting__getQueryString_Servlet_setHeaderServlet_16 extends AbstractTestCaseServlet
{
    public void bad(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data;

        while (true)
        {
            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 */
                    }
                }
            }
            break;
        }

        while (true)
        {
            if (data != null)
            {
                /* POTENTIAL FLAW: Input not verified before inclusion in header */
                response.setHeader("Location", "/author.jsp?lang=" + data);
            }
            break;
        }
    }

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

        while (true)
        {
            /* FIX: Use a hardcoded string */
            data = "foo";
            break;
        }

        while (true)
        {
            if (data != null)
            {
                /* POTENTIAL FLAW: Input not verified before inclusion in header */
                response.setHeader("Location", "/author.jsp?lang=" + data);
            }
            break;
        }

    }

    /* goodB2G() - use badsource and goodsink */
    private void goodB2G(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String data;

        while (true)
        {
            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 */
                    }
                }
            }
            break;
        }

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

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