diff options
Diffstat (limited to 'bin/tests/system/digdelv/ans8/ans.py')
| -rw-r--r-- | bin/tests/system/digdelv/ans8/ans.py | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/bin/tests/system/digdelv/ans8/ans.py b/bin/tests/system/digdelv/ans8/ans.py new file mode 100644 index 0000000..3e18edc --- /dev/null +++ b/bin/tests/system/digdelv/ans8/ans.py @@ -0,0 +1,202 @@ +# Copyright (C) Internet Systems Consortium, Inc. ("ISC") +# +# SPDX-License-Identifier: MPL-2.0 +# +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, you can obtain one at https://mozilla.org/MPL/2.0/. +# +# See the COPYRIGHT file distributed with this work for additional +# information regarding copyright ownership. + +from __future__ import print_function +import os +import sys +import signal +import socket +import select +import struct + +import dns, dns.message +from dns.rcode import * + +modes = [ + b"silent", # Do not respond + b"close", # UDP: same as silent; TCP: also close the connection + b"servfail", # Always respond with SERVFAIL + b"unstable", # Constantly switch between "silent" and "servfail" +] +mode = modes[0] +n = 0 + + +def ctrl_channel(msg): + global modes, mode, n + + msg = msg.splitlines().pop(0) + print("Received control message: %s" % msg) + + if msg in modes: + mode = msg + n = 0 + print("New mode: %s" % str(mode)) + + +def create_servfail(msg): + m = dns.message.from_wire(msg) + qname = m.question[0].name.to_text() + rrtype = m.question[0].rdtype + typename = dns.rdatatype.to_text(rrtype) + + with open("query.log", "a") as f: + f.write("%s %s\n" % (typename, qname)) + print("%s %s" % (typename, qname), end=" ") + + r = dns.message.make_response(m) + r.set_rcode(SERVFAIL) + return r + + +def sigterm(signum, frame): + print("Shutting down now...") + os.remove("ans.pid") + running = False + sys.exit(0) + + +ip4 = "10.53.0.8" + +try: + port = int(os.environ["PORT"]) +except: + port = 5300 + +try: + ctrlport = int(os.environ["EXTRAPORT1"]) +except: + ctrlport = 5300 + +query4_udp = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) +query4_udp.bind((ip4, port)) + +query4_tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM) +query4_tcp.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) +query4_tcp.bind((ip4, port)) +query4_tcp.listen(100) + +ctrl4_tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM) +ctrl4_tcp.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) +ctrl4_tcp.bind((ip4, ctrlport)) +ctrl4_tcp.listen(100) + +signal.signal(signal.SIGTERM, sigterm) + +f = open("ans.pid", "w") +pid = os.getpid() +print(pid, file=f) +f.close() + +running = True + +print("Listening on %s port %d" % (ip4, port)) +print("Listening on %s port %d" % (ip4, ctrlport)) +print("Ctrl-c to quit") + +input = [query4_udp, query4_tcp, ctrl4_tcp] + +hung_conns = [] + +while running: + try: + inputready, outputready, exceptready = select.select(input, [], []) + except select.error as e: + break + except socket.error as e: + break + except KeyboardInterrupt: + break + + for s in inputready: + if s == query4_udp: + n = n + 1 + print("UDP query received on %s" % ip4, end=" ") + msg = s.recvfrom(65535) + if ( + mode == b"silent" + or mode == b"close" + or (mode == b"unstable" and n % 2 == 1) + ): + # Do not respond. + print("NO RESPONSE (%s)" % str(mode)) + continue + elif mode == b"servfail" or (mode == b"unstable" and n % 2 == 0): + rsp = create_servfail(msg[0]) + if rsp: + print(dns.rcode.to_text(rsp.rcode())) + s.sendto(rsp.to_wire(), msg[1]) + else: + print("NO RESPONSE (can not create a response)") + else: + raise (Exception("unsupported mode: %s" % mode)) + elif s == query4_tcp: + n = n + 1 + print("TCP query received on %s" % ip4, end=" ") + conn = None + try: + if mode == b"silent" or (mode == b"unstable" and n % 2 == 1): + conn, addr = s.accept() + # Do not respond and hang the connection. + print("NO RESPONSE (%s)" % str(mode)) + hung_conns.append(conn) + continue + elif mode == b"close": + conn, addr = s.accept() + # Do not respond and close the connection. + print("NO RESPONSE (%s)" % str(mode)) + conn.close() + continue + elif mode == b"servfail" or (mode == b"unstable" and n % 2 == 0): + conn, addr = s.accept() + # get TCP message length + msg = conn.recv(2) + if len(msg) != 2: + print("NO RESPONSE (can not read the message length)") + conn.close() + continue + length = struct.unpack(">H", msg[:2])[0] + msg = conn.recv(length) + if len(msg) != length: + print("NO RESPONSE (can not read the message)") + conn.close() + continue + rsp = create_servfail(msg) + if rsp: + print(dns.rcode.to_text(rsp.rcode())) + wire = rsp.to_wire() + conn.send(struct.pack(">H", len(wire))) + conn.send(wire) + else: + print("NO RESPONSE (can not create a response)") + else: + raise (Exception("unsupported mode: %s" % mode)) + except socket.error as e: + print("NO RESPONSE (error: %s)" % str(e)) + if conn: + conn.close() + elif s == ctrl4_tcp: + print("Control channel connected") + conn = None + try: + # Handle control channel input + conn, addr = s.accept() + msg = conn.recv(1024) + if msg: + ctrl_channel(msg) + conn.close() + except s.timeout: + pass + if conn: + conn.close() + + if not running: + break |