Mailing-List: contact users-help@tomcat.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Tomcat Users List" <users@tomcat.apache.org>
From: =?UTF-8?Q?Konstantin_Prei=C3=9Fer?= <kpreisser@apache.org>
To: "'Tomcat Users List'" <users@tomcat.apache.org>
Subject: Tomcat 8.0.3 hangs when ISAPI redirector sends an AJP request without
 request body
Date: Mon, 3 Mar 2014 17:19:14 +0100
Message-ID: <003801cf36fc$52d82830$f8887890$@apache.org>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Thread-Index: Ac82+MGZOL5XDN89TAqD+w58CRjvDg==
Content-Language: de

Hi,

I observed another strange problem when using Tomcat 8.0.3 with Java =
1.7.0_51 (64-bit) on Windows Server 2012 R2, in conjunction with IIS 8.5 =
+ ISAPI Redirector 1.2.39 (the problem also happens with 1.2.37). I'm =
using the AJP NIO and HTTP NIO connectors, but the problem also happens =
with AJP BIO and AJP APR.

The problem is: When I have a servlet that directly reads the request =
body, and I send a HTTP request to IIS (GET or POST) with =
Content-Length: 0, Tomcat hangs trying to read the request body. This =
does not happen when sending the same request directly to Tomcat using =
the HTTP connector.


Consider this example servlet:

[[[
@WebServlet("/Servlet")
public class Servlet extends HttpServlet {
    private static final long serialVersionUID =3D 1L;
   =20

    protected void doGet(HttpServletRequest request, HttpServletResponse =
response) throws ServletException, IOException {
        doRequest(request, response, false);
    }

    protected void doPost(HttpServletRequest request, =
HttpServletResponse response) throws ServletException, IOException {
        doRequest(request, response, true);
    }

    private void doRequest(HttpServletRequest request, =
HttpServletResponse response, boolean isPost) throws ServletException, =
IOException {
        System.out.println("Method: " + (isPost ? "POST" : "GET") + ". =
Reading request body...");
        long readCount =3D 0;=20
       =20
        try (InputStream s =3D request.getInputStream()) {
            byte[] buf =3D new byte[4096];
            int read;
            while ((read =3D s.read(buf)) > 0)
                readCount +=3D read;
        }
       =20
        System.out.println("Reading request body finished, Byte Count: " =
+ readCount);
       =20
        response.setContentType("text/plain");
        response.setCharacterEncoding("UTF-8");
       =20
        try (PrintWriter w =3D response.getWriter()) {
            w.println("Method: " + (isPost ? "POST" : "GET") + ". =
Reading request body...");
            w.println("Request Body length in bytes: " + readCount);
        }
    }
}
]]]

This servlet directly reads the request InputStream and counts the bytes =
that it read.

When I now send the following HTTP requests directly to Tomcat (port =
8080), everything works as expected:

Request:
GET /TestWebapp/Servlet HTTP/1.1
Host: localhost
Connection: keep-alive
Content-Length: 10

0123456789

Response:
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Content-Type: text/plain;charset=3DUTF-8
Content-Length: 72
Date: Mon, 03 Mar 2014 15:39:35 GMT

Method: GET. Reading request body...
Request Body length in bytes: 10


Request:
GET /TestWebapp/Servlet HTTP/1.1
Host: localhost
Connection: keep-alive

Response:
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Content-Type: text/plain;charset=3DUTF-8
Content-Length: 71
Date: Mon, 03 Mar 2014 15:38:33 GMT

Method: GET. Reading request body...
Request Body length in bytes: 0


However, when I set the ISAPI Redirector for IIS 8.5 to forward every =
request to Tomcat, using following worker.properties:
  # Define 1 real worker using ajp13
  worker.list=3Dworker1
  # Set properties for worker1 (ajp13)
  worker.worker1.type=3Dajp13
  worker.worker1.host=3D127.0.0.1
  worker.worker1.port=3D8009

and uriworkermap.properties:
  /*=3Dworker1

Then, when I send the same requests to IIS, the one which has a body =
succeeds, but the one which doesn't have a body does not finish:

Request:
GET /TestWebapp/Servlet HTTP/1.1
Host: localhost
Connection: keep-alive
Content-Length: 10

0123456789

Response:
HTTP/1.1 200 OK
Content-Length: 72
Content-Type: text/plain;charset=3DUTF-8
Server: Microsoft-IIS/8.5
X-Powered-By: ASP.NET
Date: Mon, 03 Mar 2014 15:41:49 GMT

Method: GET. Reading request body...
Request Body length in bytes: 10


Request:
GET /TestWebapp/Servlet HTTP/1.1
Host: localhost
Connection: keep-alive

Response:
(waits forever without sending a response...)


The same happens with this request:
POST /TestWebapp/Servlet HTTP/1.1
Host: localhost
Connection: keep-alive
Content-Length: 0

Response:
(waits forever without sending a response...)


In Tomcat's log you can see that Tomcat hangs at s.read(buf), so it =
seems it somehow does not notice that the request body length is 0.


Any idea what's going on there?

Note: I do not yet have examined what AJP packets are sent between =
Tomcat and ISAPI Redirector.


Regards,
Konstantin Prei=C3=9Fer


---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org