/usr/lib/python2.7/dist-packages/google_compute_engine/network_setup/network_setup.py is in python-google-compute-engine 20180129+dfsg1-0ubuntu3.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 | #!/usr/bin/python
# Copyright 2016 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Enables the network interfaces provided in metadata."""
import fileinput
import logging.handlers
import optparse
import os
import re
import subprocess
from google_compute_engine import config_manager
from google_compute_engine import constants
from google_compute_engine import logger
from google_compute_engine import metadata_watcher
from google_compute_engine import network_utils
class NetworkSetup(object):
"""Enable network interfaces specified by metadata."""
network_interfaces = 'instance/network-interfaces'
network_path = constants.LOCALBASE + '/etc/sysconfig/network-scripts'
def __init__(self, dhclient_script=None, dhcp_command=None, debug=False):
"""Constructor.
Args:
dhclient_script: string, the path to a dhclient script used by dhclient.
dhcp_command: string, a command to enable Ethernet interfaces.
debug: bool, True if debug output should write to the console.
"""
self.dhclient_script = dhclient_script or '/sbin/google-dhclient-script'
self.dhcp_command = dhcp_command
facility = logging.handlers.SysLogHandler.LOG_DAEMON
self.logger = logger.Logger(
name='network-setup', debug=debug, facility=facility)
self.watcher = metadata_watcher.MetadataWatcher(logger=self.logger)
self.network_utils = network_utils.NetworkUtils(logger=self.logger)
self._SetupNetworkInterfaces()
def _ModifyInterface(
self, interface_config, config_key, config_value, replace=False):
"""Write a value to a config file if not already present.
Args:
interface_config: string, the path to a config file.
config_key: string, the configuration key to set.
config_value: string, the value to set for the configuration key.
replace: bool, replace the configuration option if already present.
"""
config_entry = '%s=%s' % (config_key, config_value)
if not open(interface_config).read().count(config_key):
with open(interface_config, 'a') as config:
config.write('%s\n' % config_entry)
elif replace:
for line in fileinput.input(interface_config, inplace=True):
print(re.sub(r'%s=.*' % config_key, config_entry, line.rstrip()))
def _DisableNetworkManager(self, interfaces):
"""Disable network manager management on a list of network interfaces.
Args:
interfaces: list of string, the output device names enable.
"""
for interface in interfaces:
interface_config = os.path.join(self.network_path, 'ifcfg-%s' % interface)
if os.path.exists(interface_config):
self._ModifyInterface(
interface_config, 'DEVICE', interface, replace=False)
self._ModifyInterface(
interface_config, 'NM_CONTROLLED', 'no', replace=True)
else:
with open(interface_config, 'w') as interface_file:
interface_content = [
'# Added by Google.',
'BOOTPROTO=none',
'DEFROUTE=no',
'DEVICE=%s' % interface,
'IPV6INIT=no',
'NM_CONTROLLED=no',
'NOZEROCONF=yes',
'',
]
interface_file.write('\n'.join(interface_content))
self.logger.info('Created config file for interface %s.', interface)
def _ConfigureNetwork(self, interfaces):
"""Enable the list of network interfaces.
Args:
interfaces: list of string, the output device names enable.
"""
self.logger.info('Enabling the Ethernet interfaces %s.', interfaces)
dhclient_command = ['dhclient']
if os.path.exists(self.dhclient_script):
dhclient_command += ['-sf', self.dhclient_script]
try:
subprocess.check_call(dhclient_command + ['-x'] + interfaces)
subprocess.check_call(dhclient_command + interfaces)
except subprocess.CalledProcessError:
self.logger.warning('Could not enable interfaces %s.', interfaces)
def _EnableNetworkInterfaces(self, interfaces):
"""Enable the list of network interfaces.
Args:
interfaces: list of string, the output device names to enable.
"""
# The default Ethernet interface is enabled by default. Do not attempt to
# enable interfaces if only one interface is specified in metadata.
if not interfaces or len(interfaces) <= 1:
return
if self.dhcp_command:
try:
subprocess.check_call([self.dhcp_command])
except subprocess.CalledProcessError:
self.logger.warning('Could not enable Ethernet interfaces.')
else:
if os.path.exists(self.network_path):
self._DisableNetworkManager(interfaces)
self._ConfigureNetwork(interfaces)
def _SetupNetworkInterfaces(self):
"""Get network interfaces metadata and enable each Ethernet interface."""
result = self.watcher.GetMetadata(
metadata_key=self.network_interfaces, recursive=True)
interfaces = []
for network_interface in result:
mac_address = network_interface.get('mac')
interface = self.network_utils.GetNetworkInterface(mac_address)
if interface:
interfaces.append(interface)
else:
message = 'Network interface not found for MAC address: %s.'
self.logger.warning(message, mac_address)
self._EnableNetworkInterfaces(interfaces)
def main():
parser = optparse.OptionParser()
parser.add_option(
'-d', '--debug', action='store_true', dest='debug',
help='print debug output to the console.')
(options, _) = parser.parse_args()
instance_config = config_manager.ConfigManager()
if instance_config.GetOptionBool('NetworkInterfaces', 'setup'):
NetworkSetup(
dhclient_script=instance_config.GetOptionString(
'NetworkInterfaces', 'dhclient_script'),
dhcp_command=instance_config.GetOptionString(
'NetworkInterfaces', 'dhcp_command'),
debug=bool(options.debug))
if __name__ == '__main__':
main()
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