1 files changed, 70 insertions, 0 deletions
diff --git a/bin/tests/system/tcp/tests_tcp.py b/bin/tests/system/tcp/tests_tcp.py
new file mode 100644
index 0000000..3a0a7ae
--- /dev/null
+++ b/bin/tests/system/tcp/tests_tcp.py
@@ -0,0 +1,70 @@
+#!/usr/bin/python3
+
+# 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.
+
+# pylint: disable=unused-variable
+
+import socket
+import time
+
+import pytest
+
+pytest.importorskip("dns", minversion="2.0.0")
+import dns.message
+import dns.query
+
+TIMEOUT = 10
+
+
+def create_msg(qname, qtype, edns=-1):
+    msg = dns.message.make_query(qname, qtype, use_edns=edns)
+    return msg
+
+
+def timeout():
+    return time.time() + TIMEOUT
+
+
+def create_socket(host, port):
+    sock = socket.create_connection((host, port), timeout=10)
+    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, True)
+    return sock
+
+
+# Regression test for CVE-2022-0396
+def test_close_wait(named_port):
+    with create_socket("10.53.0.7", named_port) as sock:
+        msg = create_msg("a.example.", "A")
+        (sbytes, stime) = dns.query.send_tcp(sock, msg, timeout())
+        (response, rtime) = dns.query.receive_tcp(sock, timeout())
+
+        msg = dns.message.make_query("a.example.", "A", use_edns=0, payload=1232)
+        (sbytes, stime) = dns.query.send_tcp(sock, msg, timeout())
+
+        # Shutdown the socket, but ignore the other side closing the socket
+        # first because we sent DNS message with EDNS0
+        try:
+            sock.shutdown(socket.SHUT_RDWR)
+        except ConnectionError:
+            pass
+        except OSError:
+            pass
+
+    # BIND allows one TCP client, the part above sends DNS messaage with EDNS0
+    # after the first query. BIND should react adequately because of
+    # ns7/named.dropedns and close the socket, making room for the next
+    # request. If it gets stuck in CLOSE_WAIT state, there is no connection
+    # available for the query below and it will time out.
+    with create_socket("10.53.0.7", named_port) as sock:
+        msg = create_msg("a.example.", "A")
+        (sbytes, stime) = dns.query.send_tcp(sock, msg, timeout())
+        (response, rtime) = dns.query.receive_tcp(sock, timeout())