# Copyright (c) 2013 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 logging

from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib.cros.network import ping_runner
from autotest_lib.client.common_lib.cros.network import xmlrpc_datatypes
from autotest_lib.client.common_lib.cros.network  import xmlrpc_security_types
from autotest_lib.server.cros.network import hostap_config
from autotest_lib.server.cros.network import wifi_cell_test_base


class network_WiFi_PTK(wifi_cell_test_base.WiFiCellTestBase):
    """Test that pairwise temporal key rotations work as expected."""
    version = 1

    # These settings combine to give us around 75 seconds of ping time,
    # which should be around 15 rekeys.
    PING_COUNT = 150
    PING_INTERVAL = 0.5
    REKEY_PERIOD = 5
    PING_LOSS_THRESHOLD=20

    def run_once(self):
        """Test body."""
        wpa_config = xmlrpc_security_types.WPAConfig(
                psk='chromeos',
                wpa_mode=xmlrpc_security_types.WPAConfig.MODE_MIXED_WPA,
                wpa_ciphers=[xmlrpc_security_types.WPAConfig.CIPHER_TKIP,
                             xmlrpc_security_types.WPAConfig.CIPHER_CCMP],
                wpa2_ciphers=[xmlrpc_security_types.WPAConfig.CIPHER_CCMP],
                wpa_ptk_rekey_period=self.REKEY_PERIOD)
        ap_config = hostap_config.HostapConfig(
                    frequency=2412,
                    mode=hostap_config.HostapConfig.MODE_11N_PURE,
                    security_config=wpa_config)
        # TODO(wiley) This is just until we find the source of these
        #             test failures.
        self.context.capture_host.start_capture(ap_config.frequency)
        self.context.configure(ap_config)
        assoc_params = xmlrpc_datatypes.AssociationParameters(
                ssid=self.context.router.get_ssid(),
                security_config=wpa_config)
        self.context.assert_connect_wifi(assoc_params)
        ping_config = ping_runner.PingConfig(self.context.get_wifi_addr(),
                                             count=self.PING_COUNT,
                                             interval=self.PING_INTERVAL,
                                             ignore_result=True)
        logging.info('Pinging DUT for %d seconds and rekeying '
                     'every %d seconds.',
                     self.PING_COUNT * self.PING_INTERVAL,
                     self.REKEY_PERIOD)
        ping_result = self.context.client.ping(ping_config=ping_config)
        logging.info('Ping loss percentage: %d.', ping_result.loss)
        self.output_perf_value(description='Network_wifi_PTK_PingLoss',
                value=ping_result.loss, units='percent', higher_is_better=False)
        if ping_result.loss > self.PING_LOSS_THRESHOLD:
            raise error.TestNAError('Lost ping packets %r percentage.' %
                                    ping_result.loss)
        self.context.client.shill.disconnect(assoc_params.ssid)
        self.context.router.deconfig()
        self.context.capture_host.stop_capture()