dns_server: punt
This was only used by PyAuto, but that was deleted long ago.
BUG=chromium:798946
TEST=precq passes
Change-Id: I8094a223b8027ff30bafdeb98127e6001ba01652
Reviewed-on: https://chromium-review.googlesource.com/848543
Commit-Ready: Mike Frysinger <[email protected]>
Tested-by: Mike Frysinger <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
diff --git a/client/cros/dns_server.py b/client/cros/dns_server.py
deleted file mode 100644
index 57571cb..0000000
--- a/client/cros/dns_server.py
+++ /dev/null
@@ -1,126 +0,0 @@
-# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import common, constants, logging, os, socket, stat, sys, threading, time
-
-from autotest_lib.client.bin import utils
-from autotest_lib.client.common_lib import error
-
-class LocalDns(object):
- """A wrapper around miniFakeDns that runs the server in a separate thread
- and redirects all DNS queries to it.
- """
- # This is a symlink. We look up the real path at runtime by following it.
- _resolv_bak_file = 'resolv.conf.bak'
-
- def __init__(self, fake_ip="127.0.0.1", local_port=53):
- import miniFakeDns # So we don't need to install it in the chroot.
- self._dns = miniFakeDns.DNSServer(fake_ip=fake_ip, port=local_port)
- self._stopper = threading.Event()
- self._thread = threading.Thread(target=self._dns.run,
- args=(self._stopper,))
-
- def __get_host_by_name(self, hostname):
- """Resolve the dotted-quad IPv4 address of |hostname|
-
- This used to use suave python code, like this:
- hosts = socket.getaddrinfo(hostname, 80, socket.AF_INET)
- (fam, socktype, proto, canonname, (host, port)) = hosts[0]
- return host
-
- But that hangs sometimes, and we don't understand why. So, use
- a subprocess with a timeout.
- """
- try:
- host = utils.system_output('%s -c "import socket; '
- 'print socket.gethostbyname(\'%s\')"' % (
- sys.executable, hostname),
- ignore_status=True, timeout=2)
- except Exception as e:
- logging.warning(e)
- return None
- return host or None
-
- def __attempt_resolve(self, hostname, ip, expected=True):
- logging.debug('Attempting to resolve %s to %s' % (hostname, ip))
- host = self.__get_host_by_name(hostname)
- logging.debug('Resolve attempt for %s got %s' % (hostname, host))
- return host and (host == ip) == expected
-
- def run(self):
- """Start the mock DNS server and redirect all queries to it."""
- self._thread.start()
- # Redirect all DNS queries to the mock DNS server.
- try:
- # Follow resolv.conf symlink.
- resolv = os.path.realpath(constants.RESOLV_CONF_FILE)
- # Grab path to the real file, do following work in that directory.
- resolv_dir = os.path.dirname(resolv)
- resolv_bak = os.path.join(resolv_dir, self._resolv_bak_file)
- resolv_contents = 'nameserver 127.0.0.1'
- # Test to make sure the current resolv.conf isn't already our
- # specially modified version. If this is the case, we have
- # probably been interrupted while in the middle of this test
- # in a previous run. The last thing we want to do at this point
- # is to overwrite a legitimate backup.
- if (utils.read_one_line(resolv) == resolv_contents and
- os.path.exists(resolv_bak)):
- logging.error('Current resolv.conf is setup for our local '
- 'server, and a backup already exists! '
- 'Skipping the backup step.')
- else:
- # Back up the current resolv.conf.
- os.rename(resolv, resolv_bak)
- # To stop flimflam from editing resolv.conf while we're working
- # with it, we want to make the directory -r-xr-xr-x. Open an
- # fd to the file first, so that we'll retain the ability to
- # alter it.
- resolv_fd = open(resolv, 'w')
- self._resolv_dir_mode = os.stat(resolv_dir).st_mode
- os.chmod(resolv_dir, (stat.S_IRUSR | stat.S_IXUSR |
- stat.S_IRGRP | stat.S_IXGRP |
- stat.S_IROTH | stat.S_IXOTH))
- resolv_fd.write(resolv_contents)
- resolv_fd.close()
- assert utils.read_one_line(resolv) == resolv_contents
- except Exception as e:
- logging.error(str(e))
- raise e
-
- utils.poll_for_condition(
- lambda: self.__attempt_resolve('www.google.com.', '127.0.0.1'),
- utils.TimeoutError('Timed out waiting for DNS changes.'),
- timeout=10)
-
- def stop(self):
- """Restore the backed-up DNS settings and stop the mock DNS server."""
- try:
- # Follow resolv.conf symlink.
- resolv = os.path.realpath(constants.RESOLV_CONF_FILE)
- # Grab path to the real file, do following work in that directory.
- resolv_dir = os.path.dirname(resolv)
- resolv_bak = os.path.join(resolv_dir, self._resolv_bak_file)
- os.chmod(resolv_dir, self._resolv_dir_mode)
- if os.path.exists(resolv_bak):
- os.rename(resolv_bak, resolv)
- else:
- # This probably means shill restarted during the execution
- # of our test, and has cleaned up the .bak file we created.
- raise error.TestError('Backup file %s no longer exists! '
- 'Connection manager probably crashed '
- 'during the test run.' %
- resolv_bak)
-
- utils.poll_for_condition(
- lambda: self.__attempt_resolve('www.google.com.',
- '127.0.0.1',
- expected=False),
- utils.TimeoutError('Timed out waiting to revert DNS. '
- 'resolv.conf contents are: ' +
- utils.read_one_line(resolv)),
- timeout=10)
- finally:
- # Stop the DNS server.
- self._stopper.set()
- self._thread.join()
