/* TEMPLATE GENERATED TESTCASE FILE
Filename: CWE113_HTTP_Response_Splitting__Environment_addHeaderServlet_31.java
Label Definition File: CWE113_HTTP_Response_Splitting.label.xml
Template File: sources-sinks-31.tmpl.java
*/
/*
 * @description
 * CWE: 113 HTTP Response Splitting
 * BadSource: Environment Read data from an environment variable
 * GoodSource: A hardcoded string
 * Sinks: addHeaderServlet
 *    GoodSink: URLEncode input
 *    BadSink : querystring to addHeader()
 * Flow Variant: 31 Data flow: make a copy of data within the same method
 *
 * */




import javax.servlet.http.*;

import java.net.URLEncoder;

public class CWE113_HTTP_Response_Splitting__Environment_addHeaderServlet_31 extends AbstractTestCaseServlet
{
    public void bad(HttpServletRequest request, HttpServletResponse response) throws Throwable
    {
        String dataCopy;
        {
            String data;

            /* get environment variable ADD */
            /* POTENTIAL FLAW: Read data from an environment variable */
            data = System.getenv("ADD");

            dataCopy = data;
        }
        {
            String data = dataCopy;

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

        }
    }

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

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

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

            dataCopy = data;
        }
        {
            String data = dataCopy;

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

        }
    }

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

            /* get environment variable ADD */
            /* POTENTIAL FLAW: Read data from an environment variable */
            data = System.getenv("ADD");

            dataCopy = data;
        }
        {
            String data = dataCopy;

            /* 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);
            }

        }
    }

    /* 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);
    }
}
