Ondřej SurýandEvan Hunt
5c17919019
The TCP connection reset test starts mock UDP and TCP server which always returns empty DNS answer with TC bit set over UDP and resets the TCP connection after five seconds. When tested without the fix, the DNS query to 10.53.0.2 times out and the ns2 server hangs at shutdown.
100 lines
2.1 KiB
Python
100 lines
2.1 KiB
Python
############################################################################
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# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
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#
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# This Source Code Form is subject to the terms of the Mozilla Public
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# License, v. 2.0. If a copy of the MPL was not distributed with this
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# file, you can obtain one at https://mozilla.org/MPL/2.0/.
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#
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# See the COPYRIGHT file distributed with this work for additional
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# information regarding copyright ownership.
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############################################################################
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import os
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import select
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import signal
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import socket
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import sys
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import time
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import dns.flags
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import dns.message
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def port():
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env_port = os.getenv("PORT")
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if env_port is None:
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env_port = 5300
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else:
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env_port = int(env_port)
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return env_port
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def udp_listen(port):
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udp = socket.socket(type=socket.SOCK_DGRAM)
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udp.bind(('10.53.0.3', port))
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return udp
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def tcp_listen(port):
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tcp = socket.socket(type=socket.SOCK_STREAM)
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tcp.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
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tcp.bind(('10.53.0.3', port))
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tcp.listen(100)
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return tcp
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def udp_tc_once(udp):
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qrybytes, clientaddr = udp.recvfrom(65535)
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qry = dns.message.from_wire(qrybytes)
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answ = dns.message.make_response(qry)
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answ.flags |= dns.flags.TC
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answbytes = answ.to_wire()
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udp.sendto(answbytes, clientaddr)
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def tcp_once(tcp):
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csock, _clientaddr = tcp.accept()
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time.sleep(5)
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csock.close()
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def sigterm(signum, frame):
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os.remove('ans.pid')
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sys.exit(0)
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def write_pid():
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with open('ans.pid', 'w') as f:
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pid = os.getpid()
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f.write("{}".format(pid))
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signal.signal(signal.SIGTERM, sigterm)
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write_pid()
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udp = udp_listen(port())
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tcp = tcp_listen(port())
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input = [udp, tcp]
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while True:
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try:
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inputready, outputready, exceptready = select.select(input, [], [])
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except select.error:
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break
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except socket.error:
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break
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except KeyboardInterrupt:
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break
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for s in inputready:
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if s == udp:
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udp_tc_once(udp)
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if s == tcp:
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tcp_once(tcp)
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sigterm(signal.SIGTERM, 0)
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