[Zope-dev] passive FTP to Zope with a specified port-range

Mr Tobias Schiebeck tobias.schiebeck@man.ac.uk
Fri, 02 Aug 2002 11:53:06 +0100


Hi,

I'm trying to modify the zope ftp-access to specify a port range 
within the server selects the ports for the passive ftp communication
with the ftp-clients. This is in order to have the Zope server behind
a firewall blocking more then the privileged ports only. 

I managed to modify the passive_acceptor within the medusa ftp server
file. The problem I have is that certain FTP clients (e.g. gftp) 
close there connection because of messages coming from the server.

The code I have modified is in 

   /usr/lib/zope/ZServer/medusa/ftp_server.py

class passive_acceptor (asyncore.dispatcher):
	ready = None

	def __init__ (self, control_channel):
		# connect_fun (conn, addr)
		asyncore.dispatcher.__init__ (self)
		self.control_channel = control_channel
		self.create_socket (socket.AF_INET, socket.SOCK_STREAM)
		to=open('/tmp/zope.log','a')
		for i in range(10000,11000): 
			# bind to an address on the interface that the
			# control connection is coming from.
			to.write("ftp connection - port %d\n"%i)
			bres = self.bind ((
				self.control_channel.getsockname()[0],
				i
				))
			to.write("ftp connection - bind:"+`bres`+"\n")
			if bres == None :
				break
		self.addr = self.getsockname()
		self.listen (1)
		to.close()

Accessing the Zope-server through a firewall that has only the ports
10000 to 11000 open using gftp allows the firs connection but 
disconnects with an error message when I change the directory.

The error message is:

451 Server Error: socket.error, (98,'Address already in use'): file:
/usr/lib/zope/ZServer/medusa/asyncore.py line: 250

Do you have any hints on this?

Thanks and Best Regards

Tobias

-- 
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Tobias Schiebeck                           tobias.schiebeck@man.ac.uk
International AVS Centre              Manchester Visualization Centre
http://www.iavsc.org                          tel: (+44) 161-275-6870
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