[tproxy] connection go to CLOSE_WAIT after sending FIN

[Eyal Rundstein]

As far as I understand, the RFC 793 states that the correct behavior is
to go to state FIN_WAIT_2. 
We go to CLOSE_WAIT only if we receive FIN and send ACK. 
Page 21:
CLOSE-WAIT - represents waiting for a connection termination request
		from the LOCAL user.
FIN-WAIT-2 - represents waiting for a connection termination request
    from the REMOTE TCP.

E.R

-----Original Message-----
From: Jan Engelhardt [mailto:jengelh at linux01.gwdg.de] 
Sent: Monday, December 11, 2006 2:38 PM
To: Eyal Rundstein
Cc: tproxy at lists.balabit.hu
Subject: Re: [tproxy] connection go to CLOSE_WAIT after sending FIN


>Hi,
>I am using kernel 2.4.32 with tproxy version 2.0.2.
>My client is a transparent proxy.
>My client opens a transparent connection to the server, sends a message

>and then closes the connection with FIN. The server replies with an 
>ACK, WITHOUT sending a FIN.
>Now I see that the connection stays in the ip_conntrack table in 
>CLOSE_WAIT state. During that time I can not reuse the connection. 
>(SYNs to the same dest are not sent).

This is correct, as per RFC 793 page 21 and page 39.

>1) Isn't the correct behavior for that connection is to go to 
>FIN_WAIT_2 state? Is it a bug?
>2) The CLOSE_WAIT timeout is 500 seconds. Is there a way I can still 
>open a new connection to the same destination?

setsockopt SO_REUSEADDR may help.

>- When I use an older kernel (2.4.18) with old tproxy (version 23) I 
>don't see this problem.
> 
>Help is appreciated.
>Thanks in advance,
>E.R
> 
>

	-`J'
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