[wt4hq] tunnelsrv is crashing all the time

[Olivier F5MZN]

Hello,

Mario Lorenz wrote:
> Am 14. Jul 2007, um 14:28:38 schrieb Dieter Kritzer:
>> our linux-tunnelsrv is crashing very 5 minutes.
>>
>> any idea?
> 
> I've found the bug. Finally. Extremely well hidden.
> in tx_proc the call to _send() has a "+1" in the end.
> That will make the if (nBytesSent == SOCKET_ERROR) wrong.
> SocketError is defined as -1, and the -1 error code is thus
> changed into a 0, so the whole error handling logic does
> not kick in.
> So when _send() hits an error (full buffer) it will go into
> a neverending loop...
> 
> The problem we are having now is that the tunnel client, if the
> connection breaks for whatever reason, when trying to reconnect,
> will send garbage (wt protocol data) as username/password...
> But that requires fixing the client which we cannot do...

Wow, well seen Mario!!

Can you approve the following modification:

In the "int tx_proc(void)" function

Replace :

	/* Try to send the bloc of data to the client */
	/* Note that one must not send the null-terminal character! */
	nBytesSent = _send(tun->sock, szBuffer, nBufferLen - 1, 0) + 1;

by
	/* Try to send the bloc of data to the client */
	/* Note that one must not send the null-terminal character! */
	nBytesSent = _send(tun->sock, szBuffer, nBufferLen - 1, 0);

and replace:

          /* Remove the sent bytes from the TX buffer */
          buffer_read(&(tun->pszTxBuffer), &(tun->nTxBufferSize), 
szBuffer, nBytesSent, 0);

by

          /* Remove the sent bytes from the TX buffer */
          buffer_read(&(tun->pszTxBuffer), &(tun->nTxBufferSize), 
szBuffer, nBytesSent + 1, 0);


Regarding your suggestion amending MSG_NOSIGNAL. Is it enought to add 
the MSG_NOSIGNAL here?

/*
  * Send a buffers to the socket
  */
static int _send(SOCKET s, const char * buf, int len, int flags)
{
	return send(s, buf, len, MSG_NOSIGNAL | flags);
}

I'll prepare the download area with these mods including without waiting 
for your reply in order to give the other team the chance to have a 
tunnel server working for the last hours of the contest!

After that I'll try to figure out what happens with the client.

Thanks a lot Mario!
-- 
Olivier / f5mzn