Adding upstream version 1:9.16.44.upstream/1%9.16.44upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 209 insertions, 0 deletions

diff --git a/bin/tests/system/shutdown/tests_shutdown.py b/bin/tests/system/shutdown/tests_shutdown.py
new file mode 100755
index 0000000..b6083b7
--- /dev/null
+++ b/bin/tests/system/shutdown/tests_shutdown.py
@@ -0,0 +1,209 @@
+#!/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.
+
+from concurrent.futures import ThreadPoolExecutor, as_completed
+import os
+import random
+import signal
+import subprocess
+from string import ascii_lowercase as letters
+import time
+
+import pytest
+
+pytest.importorskip("dns")
+import dns.exception
+import dns.resolver
+
+
+def do_work(named_proc, resolver, rndc_cmd, kill_method, n_workers, n_queries):
+    """Creates a number of A queries to run in parallel
+    in order simulate a slightly more realistic test scenario.
+
+    The main idea of this function is to create and send a bunch
+    of A queries to a target named instance and during this process
+    a request for shutting down named will be issued.
+
+    In the process of shutting down named, a couple control connections
+    are created (by launching rndc) to ensure that the crash was fixed.
+
+    if kill_method=="rndc" named will be asked to shutdown by
+    means of rndc stop.
+    if kill_method=="sigterm" named will be killed by SIGTERM on
+    POSIX systems or by TerminateProcess() on Windows systems.
+
+    :param named_proc: named process instance
+    :type named_proc: subprocess.Popen
+
+    :param resolver: target resolver
+    :type resolver: dns.resolver.Resolver
+
+    :param rndc_cmd: rndc command with default arguments
+    :type rndc_cmd: list of strings, e.g. ["rndc", "-p", "23750"]
+
+    :kill_method: "rndc" or "sigterm"
+    :type kill_method: str
+
+    :param n_workers: Number of worker threads to create
+    :type n_workers: int
+
+    :param n_queries: Total number of queries to send
+    :type n_queries: int
+    """
+    # pylint: disable-msg=too-many-arguments
+    # pylint: disable-msg=too-many-locals
+
+    # helper function, args must be a list or tuple with arguments to rndc.
+    def launch_rndc(args):
+        return subprocess.call(rndc_cmd + args, timeout=10)
+
+    # We're going to execute queries in parallel by means of a thread pool.
+    # dnspython functions block, so we need to circunvent that.
+    with ThreadPoolExecutor(n_workers + 1) as executor:
+        # Helper dict, where keys=Future objects and values are tags used
+        # to process results later.
+        futures = {}
+
+        # 50% of work will be A queries.
+        # 1 work will be rndc stop.
+        # Remaining work will be rndc status (so we test parallel control
+        #  connections that were crashing named).
+        shutdown = True
+        for i in range(n_queries):
+            if i < (n_queries // 2):
+                # Half work will be standard A queries.
+                # Among those we split 50% queries relname='www',
+                # 50% queries relname=random characters
+                if random.randrange(2) == 1:
+                    tag = "good"
+                    relname = "www"
+                else:
+                    tag = "bad"
+                    length = random.randint(4, 10)
+                    relname = "".join(
+                        letters[random.randrange(len(letters))] for i in range(length)
+                    )
+
+                qname = relname + ".test"
+                futures[executor.submit(resolver.query, qname, "A")] = tag
+            elif shutdown:  # We attempt to stop named in the middle
+                shutdown = False
+                if kill_method == "rndc":
+                    futures[executor.submit(launch_rndc, ["stop"])] = "stop"
+                else:
+                    futures[executor.submit(named_proc.terminate)] = "kill"
+            else:
+                # We attempt to send couple rndc commands while named is
+                # being shutdown
+                futures[executor.submit(launch_rndc, ["status"])] = "status"
+
+        ret_code = -1
+        for future in as_completed(futures):
+            try:
+                result = future.result()
+                # If tag is "stop", result is an instance of
+                # subprocess.CompletedProcess, then we check returncode
+                # attribute to know if rncd stop command finished successfully.
+                #
+                # if tag is "kill" then the main function will check if
+                # named process exited gracefully after SIGTERM signal.
+                if futures[future] == "stop":
+                    ret_code = result
+
+            except (
+                dns.resolver.NXDOMAIN,
+                dns.resolver.NoNameservers,
+                dns.exception.Timeout,
+            ):
+                pass
+
+        if kill_method == "rndc":
+            assert ret_code == 0
+
+
+def wait_for_named_loaded(resolver, retries=10):
+    for _ in range(retries):
+        try:
+            resolver.query("version.bind", "TXT", "CH")
+            return True
+        except (dns.resolver.NoNameservers, dns.exception.Timeout):
+            time.sleep(1)
+    return False
+
+
+def wait_for_proc_termination(proc, max_timeout=10):
+    for _ in range(max_timeout):
+        if proc.poll() is not None:
+            return True
+        time.sleep(1)
+
+    proc.send_signal(signal.SIGABRT)
+    for _ in range(max_timeout):
+        if proc.poll() is not None:
+            return True
+        time.sleep(1)
+
+    return False
+
+
+def test_named_shutdown(named_port, control_port):
+    # pylint: disable-msg=too-many-locals
+    cfg_dir = os.path.join(os.getcwd(), "resolver")
+    assert os.path.isdir(cfg_dir)
+
+    cfg_file = os.path.join(cfg_dir, "named.conf")
+    assert os.path.isfile(cfg_file)
+
+    named = os.getenv("NAMED")
+    assert named is not None
+
+    rndc = os.getenv("RNDC")
+    assert rndc is not None
+
+    systest_dir = os.getenv("SYSTEMTESTTOP")
+    assert systest_dir is not None
+
+    # rndc configuration resides in $SYSTEMTESTTOP/common/rndc.conf
+    rndc_cfg = os.path.join(systest_dir, "common", "rndc.conf")
+    assert os.path.isfile(rndc_cfg)
+
+    # rndc command with default arguments.
+    rndc_cmd = [rndc, "-c", rndc_cfg, "-p", str(control_port), "-s", "10.53.0.3"]
+
+    # We create a resolver instance that will be used to send queries.
+    resolver = dns.resolver.Resolver()
+    resolver.nameservers = ["10.53.0.3"]
+    resolver.port = named_port
+
+    # We test named shutting down using two methods:
+    # Method 1: using rndc ctop
+    # Method 2: killing with SIGTERM
+    # In both methods named should exit gracefully.
+    for kill_method in ("rndc", "sigterm"):
+        named_cmdline = [named, "-c", cfg_file, "-f"]
+        with subprocess.Popen(named_cmdline, cwd=cfg_dir) as named_proc:
+            try:
+                assert named_proc.poll() is None, "named isn't running"
+                assert wait_for_named_loaded(resolver)
+                do_work(
+                    named_proc,
+                    resolver,
+                    rndc_cmd,
+                    kill_method,
+                    n_workers=12,
+                    n_queries=16,
+                )
+                assert wait_for_proc_termination(named_proc)
+                assert named_proc.returncode == 0, "named crashed"
+            finally:  # Ensure named is terminated in case of an exception
+                named_proc.kill()