# Copyright (c) 2011 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 datetime import collections import logging import os import random import time from autotest_lib.client.common_lib import error from autotest_lib.client.common_lib.cros import path_utils from autotest_lib.client.common_lib.cros import virtual_ethernet_pair from autotest_lib.client.common_lib.cros.network import interface from autotest_lib.client.common_lib.cros.network import iw_runner from autotest_lib.client.common_lib.cros.network import ping_runner from autotest_lib.server.cros.network import packet_capturer NetDev = collections.namedtuple('NetDev', ['inherited', 'phy', 'if_name', 'if_type']) class LinuxSystem(object): """Superclass for test machines running Linux. Provides a common point for routines that use the cfg80211 userspace tools to manipulate the wireless stack, regardless of the role they play. Currently the commands shared are the init, which queries for wireless devices, along with start_capture and stop_capture. More commands may migrate from site_linux_router as appropriate to share. """ CAPABILITY_5GHZ = '5ghz' CAPABILITY_MULTI_AP = 'multi_ap' CAPABILITY_MULTI_AP_SAME_BAND = 'multi_ap_same_band' CAPABILITY_IBSS = 'ibss_supported' CAPABILITY_SEND_MANAGEMENT_FRAME = 'send_management_frame' CAPABILITY_TDLS = 'tdls' CAPABILITY_VHT = 'vht' BRIDGE_INTERFACE_NAME = 'br0' MIN_SPATIAL_STREAMS = 2 MAC_BIT_LOCAL = 0x2 # Locally administered. MAC_BIT_MULTICAST = 0x1 MAC_RETRY_LIMIT = 1000 @property def capabilities(self): """@return iterable object of AP capabilities for this system.""" if self._capabilities is None: self._capabilities = self.get_capabilities() logging.info('%s system capabilities: %r', self.role, self._capabilities) return self._capabilities @property def board(self): """@return string self reported board of this device.""" if self._board is None: # Remove 'board:' prefix. self._board = self.host.get_board().split(':')[1] return self._board def __init__(self, host, role, inherit_interfaces=False): self.host = host self.role = role self.inherit_interfaces = inherit_interfaces self.__setup() def __setup(self): """Set up this system. Can be used either to complete initialization of a LinuxSystem object, or to re-establish a good state after a reboot. """ # Command locations. cmd_iw = path_utils.must_be_installed('/usr/sbin/iw', host=self.host) self.cmd_ip = path_utils.must_be_installed('/usr/sbin/ip', host=self.host) self.cmd_readlink = '%s -l' % path_utils.must_be_installed( '/bin/ls', host=self.host) self._packet_capturer = packet_capturer.get_packet_capturer( self.host, host_description=self.role, cmd_ip=self.cmd_ip, cmd_iw=cmd_iw, ignore_failures=True) self.iw_runner = iw_runner.IwRunner(remote_host=self.host, command_iw=cmd_iw) self._phy_list = None self.phys_for_frequency, self.phy_bus_type = self._get_phy_info() self._interfaces = [] for interface in self.iw_runner.list_interfaces(): if self.inherit_interfaces: self._interfaces.append(NetDev(inherited=True, if_name=interface.if_name, if_type=interface.if_type, phy=interface.phy)) else: self.iw_runner.remove_interface(interface.if_name) self._wlanifs_in_use = [] self._local_macs_in_use = set() self._capture_interface = None self._board = None # Some uses of LinuxSystem don't use the interface allocation facility. # Don't force us to remove all the existing interfaces if this facility # is not desired. self._wlanifs_initialized = False self._capabilities = None self._ping_runner = ping_runner.PingRunner(host=self.host) self._bridge_interface = None self._virtual_ethernet_pair = None @property def phy_list(self): """@return iterable object of PHY descriptions for this system.""" if self._phy_list is None: self._phy_list = self.iw_runner.list_phys() return self._phy_list def _phy_by_name(self, phy_name): """@return IwPhy for PHY with name |phy_name|, or None.""" for phy in self._phy_list: if phy.name == phy_name: return phy else: return None def _get_phy_info(self): """Get information about WiFi devices. Parse the output of 'iw list' and some of sysfs and return: A dict |phys_for_frequency| which maps from each frequency to a list of phys that support that channel. A dict |phy_bus_type| which maps from each phy to the bus type for each phy. @return phys_for_frequency, phy_bus_type tuple as described. """ phys_for_frequency = {} phy_caps = {} phy_list = [] for phy in self.phy_list: phy_list.append(phy.name) for band in phy.bands: for mhz in band.frequencies: if mhz not in phys_for_frequency: phys_for_frequency[mhz] = [phy.name] else: phys_for_frequency[mhz].append(phy.name) phy_bus_type = {} for phy in phy_list: phybus = 'unknown' command = '%s /sys/class/ieee80211/%s' % (self.cmd_readlink, phy) devpath = self.host.run(command).stdout if '/usb' in devpath: phybus = 'usb' elif '/mmc' in devpath: phybus = 'sdio' elif '/pci' in devpath: phybus = 'pci' phy_bus_type[phy] = phybus logging.debug('Got phys for frequency: %r', phys_for_frequency) return phys_for_frequency, phy_bus_type def _create_bridge_interface(self): """Create a bridge interface.""" self.host.run('%s link add name %s type bridge' % (self.cmd_ip, self.BRIDGE_INTERFACE_NAME)) self.host.run('%s link set dev %s up' % (self.cmd_ip, self.BRIDGE_INTERFACE_NAME)) self._bridge_interface = self.BRIDGE_INTERFACE_NAME def _create_virtual_ethernet_pair(self): """Create a virtual ethernet pair.""" self._virtual_ethernet_pair = virtual_ethernet_pair.VirtualEthernetPair( interface_ip=None, peer_interface_ip=None, host=self.host) self._virtual_ethernet_pair.setup() def _get_unique_mac(self): """Get a MAC address that is likely to be unique. Generates a MAC address that is a) guaranteed not to be in use on this host, and b) likely to be unique within the test cell. @return string MAC address. """ # We use SystemRandom to reduce the likelyhood of coupling # across systems. (The default random class might, e.g., seed # itself based on wall-clock time.) sysrand = random.SystemRandom() for tries in xrange(0, self.MAC_RETRY_LIMIT): mac_addr = '%02x:%02x:%02x:%02x:%02x:%02x' % ( (sysrand.getrandbits(8) & ~self.MAC_BIT_MULTICAST) | self.MAC_BIT_LOCAL, sysrand.getrandbits(8), sysrand.getrandbits(8), sysrand.getrandbits(8), sysrand.getrandbits(8), sysrand.getrandbits(8)) if mac_addr not in self._local_macs_in_use: self._local_macs_in_use.add(mac_addr) return mac_addr else: raise error.TestError('Failed to find a new MAC address') def _phy_in_use(self, phy_name): """Determine whether or not a PHY is used by an active DEV @return bool True iff PHY is in use. """ for net_dev in self._wlanifs_in_use: if net_dev.phy == phy_name: return True return False def remove_interface(self, interface): """Remove an interface from a WiFi device. @param interface string interface to remove (e.g. wlan0). """ self.release_interface(interface) self.host.run('%s link set %s down' % (self.cmd_ip, interface)) self.iw_runner.remove_interface(interface) for net_dev in self._interfaces: if net_dev.if_name == interface: self._interfaces.remove(net_dev) break def close(self): """Close global resources held by this system.""" logging.debug('Cleaning up host object for %s', self.role) self._packet_capturer.close() # Release and remove any interfaces that we create. for net_dev in self._wlanifs_in_use: self.release_interface(net_dev.if_name) for net_dev in self._interfaces: if net_dev.inherited: continue self.remove_interface(net_dev.if_name) if self._bridge_interface is not None: self.remove_bridge_interface() if self._virtual_ethernet_pair is not None: self.remove_ethernet_pair_interface() self.host.close() self.host = None def reboot(self, timeout): """Reboot this system, and restore it to a known-good state. @param timeout Maximum seconds to wait for system to return. """ self.host.reboot(timeout=timeout, wait=True) self.__setup() def get_capabilities(self): caps = set() phymap = self.phys_for_frequency if [freq for freq in phymap.iterkeys() if freq > 5000]: # The frequencies are expressed in megaherz caps.add(self.CAPABILITY_5GHZ) if [freq for freq in phymap.iterkeys() if len(phymap[freq]) > 1]: caps.add(self.CAPABILITY_MULTI_AP_SAME_BAND) caps.add(self.CAPABILITY_MULTI_AP) elif len(self.phy_bus_type) > 1: caps.add(self.CAPABILITY_MULTI_AP) for phy in self.phy_list: if ('tdls_mgmt' in phy.commands or 'tdls_oper' in phy.commands or 'T-DLS' in phy.features): caps.add(self.CAPABILITY_TDLS) if phy.support_vht: caps.add(self.CAPABILITY_VHT) if any([iw_runner.DEV_MODE_IBSS in phy.modes for phy in self.phy_list]): caps.add(self.CAPABILITY_IBSS) return caps def start_capture(self, frequency, ht_type=None, snaplen=None, filename=None): """Start a packet capture. @param frequency int frequency of channel to capture on. @param ht_type string one of (None, 'HT20', 'HT40+', 'HT40-'). @param snaplen int number of bytes to retain per capture frame. @param filename string filename to write capture to. """ if self._packet_capturer.capture_running: self.stop_capture() self._capture_interface = self.get_wlanif(frequency, 'monitor') full_interface = [net_dev for net_dev in self._interfaces if net_dev.if_name == self._capture_interface][0] # If this is the only interface on this phy, we ought to configure # the phy with a channel and ht_type. Otherwise, inherit the settings # of the phy as they stand. if len([net_dev for net_dev in self._interfaces if net_dev.phy == full_interface.phy]) == 1: self._packet_capturer.configure_raw_monitor( self._capture_interface, frequency, ht_type=ht_type) else: self.host.run('%s link set %s up' % (self.cmd_ip, self._capture_interface)) # Start the capture. if filename: remote_path = os.path.join('/tmp', os.path.basename(filename)) else: remote_path = None self._packet_capturer.start_capture( self._capture_interface, './debug/', snaplen=snaplen, remote_file=remote_path) def stop_capture(self, save_dir=None, save_filename=None): """Stop a packet capture. @param save_dir string path to directory to save pcap files in. @param save_filename string basename of file to save pcap in locally. """ if not self._packet_capturer.capture_running: return results = self._packet_capturer.stop_capture( local_save_dir=save_dir, local_pcap_filename=save_filename) self.release_interface(self._capture_interface) self._capture_interface = None return results def sync_host_times(self): """Set time on our DUT to match local time.""" epoch_seconds = time.time() busybox_format = '%Y%m%d%H%M.%S' busybox_date = datetime.datetime.utcnow().strftime(busybox_format) self.host.run('date -u --set=@%s 2>/dev/null || date -u %s' % (epoch_seconds, busybox_date)) def _get_phy_for_frequency(self, frequency, phytype, spatial_streams): """Get a phy appropriate for a frequency and phytype. Return the most appropriate phy interface for operating on the frequency |frequency| in the role indicated by |phytype|. Prefer idle phys to busy phys if any exist. Secondarily, show affinity for phys that use the bus type associated with this phy type. @param frequency int WiFi frequency of phy. @param phytype string key of phytype registered at construction time. @param spatial_streams int number of spatial streams required. @return string name of phy to use. """ phy_objs = [] for phy_name in self.phys_for_frequency[frequency]: phy_obj = self._phy_by_name(phy_name) num_antennas = min(phy_obj.avail_rx_antennas, phy_obj.avail_tx_antennas) if num_antennas >= spatial_streams: phy_objs.append(phy_obj) elif num_antennas == 0: logging.warning( 'Allowing use of %s, which reports zero antennas', phy_name) phy_objs.append(phy_obj) else: logging.debug( 'Filtering out %s, which reports only %d antennas', phy_name, num_antennas) busy_phys = set(net_dev.phy for net_dev in self._wlanifs_in_use) idle_phy_objs = [phy_obj for phy_obj in phy_objs if phy_obj.name not in busy_phys] phy_objs = idle_phy_objs or phy_objs phy_objs.sort(key=lambda phy_obj: min(phy_obj.avail_rx_antennas, phy_obj.avail_tx_antennas), reverse=True) phys = [phy_obj.name for phy_obj in phy_objs] preferred_bus = {'monitor': 'usb', 'managed': 'pci'}.get(phytype) preferred_phys = [phy for phy in phys if self.phy_bus_type[phy] == preferred_bus] phys = preferred_phys or phys return phys[0] def _get_wlanif(self, phytype, spatial_streams, frequency, same_phy_as): """Get a WiFi device that supports the given frequency and phytype. We simply find or create a suitable DEV. It is left to the caller to actually configure the frequency and bring up the interface. @param phytype string type of phy (e.g. 'monitor'). @param spatial_streams int number of spatial streams required. @param frequency int WiFi frequency to support. @param same_phy_as string create the interface on the same phy as this. @return NetDev WiFi device. """ if frequency and same_phy_as: raise error.TestError( 'Can not combine |frequency| and |same_phy_as|') if not (frequency or same_phy_as): raise error.TestError( 'Must specify one of |frequency| or |same_phy_as|') if spatial_streams is None: spatial_streams = self.MIN_SPATIAL_STREAMS if same_phy_as: for net_dev in self._interfaces: if net_dev.if_name == same_phy_as: phy = net_dev.phy break else: raise error.TestFail('Unable to find phy for interface %s' % same_phy_as) elif frequency in self.phys_for_frequency: phy = self._get_phy_for_frequency( frequency, phytype, spatial_streams) else: raise error.TestFail('Unable to find phy for frequency %d' % frequency) # If we have a suitable unused interface sitting around on this # phy, reuse it. for net_dev in set(self._interfaces) - set(self._wlanifs_in_use): if net_dev.phy == phy and net_dev.if_type == phytype: break else: # Because we can reuse interfaces, we have to iteratively find a # good interface name. name_exists = lambda name: bool([net_dev for net_dev in self._interfaces if net_dev.if_name == name]) if_name = lambda index: '%s%d' % (phytype, index) if_index = len(self._interfaces) while name_exists(if_name(if_index)): if_index += 1 net_dev = NetDev(phy=phy, if_name=if_name(if_index), if_type=phytype, inherited=False) self._interfaces.append(net_dev) self.iw_runner.add_interface(phy, net_dev.if_name, phytype) # Link must be down to reconfigure MAC address. self.host.run('%s link set dev %s down' % ( self.cmd_ip, net_dev.if_name)) if same_phy_as: self.clone_mac_address(src_dev=same_phy_as, dst_dev=net_dev.if_name) else: self.ensure_unique_mac(net_dev) return net_dev def get_configured_interface(self, phytype, spatial_streams=None, frequency=None, same_phy_as=None): """Get a WiFi device that supports the given frequency and phytype. The device's link state will be UP, and (where possible) the device will be configured to operate on |frequency|. @param phytype string type of phy (e.g. 'monitor'). @param spatial_streams int number of spatial streams required. @param frequency int WiFi frequency to support. @param same_phy_as string create the interface on the same phy as this. @return string WiFi device. """ net_dev = self._get_wlanif( phytype, spatial_streams, frequency, same_phy_as) self.host.run('%s link set dev %s up' % (self.cmd_ip, net_dev.if_name)) if frequency: if phytype == 'managed': logging.debug('Skipped setting frequency for DEV %s ' 'since managed mode DEVs roam across APs.', net_dev.if_name) elif same_phy_as or self._phy_in_use(net_dev.phy): logging.debug('Skipped setting frequency for DEV %s ' 'since PHY %s is already in use', net_dev.if_name, net_dev.phy) else: self.iw_runner.set_freq(net_dev.if_name, frequency) self._wlanifs_in_use.append(net_dev) return net_dev.if_name # TODO(quiche): Deprecate this, in favor of get_configured_interface(). # crbug.com/512169. def get_wlanif(self, frequency, phytype, spatial_streams=None, same_phy_as=None): """Get a WiFi device that supports the given frequency and phytype. We simply find or create a suitable DEV. It is left to the caller to actually configure the frequency and bring up the interface. @param frequency int WiFi frequency to support. @param phytype string type of phy (e.g. 'monitor'). @param spatial_streams int number of spatial streams required. @param same_phy_as string create the interface on the same phy as this. @return string WiFi device. """ net_dev = self._get_wlanif( phytype, spatial_streams, frequency, same_phy_as) self._wlanifs_in_use.append(net_dev) return net_dev.if_name def ensure_unique_mac(self, net_dev): """Ensure MAC address of |net_dev| meets uniqueness requirements. The Linux kernel does not allow multiple APs with the same BSSID on the same PHY (at least, with some drivers). Hence, we want to ensure that the DEVs for a PHY have unique MAC addresses. Note that we do not attempt to make the MACs unique across PHYs, because some tests deliberately create such scenarios. @param net_dev NetDev to uniquify. """ if net_dev.if_type == 'monitor': return our_ifname = net_dev.if_name our_phy = net_dev.phy our_mac = interface.Interface(our_ifname, self.host).mac_address sibling_devs = [dev for dev in self._interfaces if (dev.phy == our_phy and dev.if_name != our_ifname and dev.if_type != 'monitor')] sibling_macs = ( interface.Interface(sib_dev.if_name, self.host).mac_address for sib_dev in sibling_devs) if our_mac in sibling_macs: self.configure_interface_mac(our_ifname, self._get_unique_mac()) def configure_interface_mac(self, wlanif, new_mac): """Change the MAC address for an interface. @param wlanif string name of device to reconfigure. @param new_mac string MAC address to assign (e.g. '00:11:22:33:44:55') """ self.host.run('%s link set %s address %s' % (self.cmd_ip, wlanif, new_mac)) def clone_mac_address(self, src_dev=None, dst_dev=None): """Copy the MAC address from one interface to another. @param src_dev string name of device to copy address from. @param dst_dev string name of device to copy address to. """ self.configure_interface_mac( dst_dev, interface.Interface(src_dev, self.host).mac_address) def release_interface(self, wlanif): """Release a device allocated throuhg get_wlanif(). @param wlanif string name of device to release. """ for net_dev in self._wlanifs_in_use: if net_dev.if_name == wlanif: self._wlanifs_in_use.remove(net_dev) def get_bridge_interface(self): """Return the bridge interface, create one if it is not created yet. @return string name of bridge interface. """ if self._bridge_interface is None: self._create_bridge_interface() return self._bridge_interface def remove_bridge_interface(self): """Remove the bridge interface that's been created.""" if self._bridge_interface is not None: self.host.run('%s link delete %s type bridge' % (self.cmd_ip, self._bridge_interface)) self._bridge_interface = None def add_interface_to_bridge(self, interface): """Add an interface to the bridge interface. This will create the bridge interface if it is not created yet. @param interface string name of the interface to add to the bridge. """ if self._bridge_interface is None: self._create_bridge_interface() self.host.run('%s link set dev %s master %s' % (self.cmd_ip, interface, self._bridge_interface)) def get_virtual_ethernet_master_interface(self): """Return the master interface of the virtual ethernet pair. @return string name of the master interface of the virtual ethernet pair. """ if self._virtual_ethernet_pair is None: self._create_virtual_ethernet_pair() return self._virtual_ethernet_pair.interface_name def get_virtual_ethernet_peer_interface(self): """Return the peer interface of the virtual ethernet pair. @return string name of the peer interface of the virtual ethernet pair. """ if self._virtual_ethernet_pair is None: self._create_virtual_ethernet_pair() return self._virtual_ethernet_pair.peer_interface_name def remove_ethernet_pair_interface(self): """Remove the virtual ethernet pair that's been created.""" if self._virtual_ethernet_pair is not None: self._virtual_ethernet_pair.teardown() self._virtual_ethernet_pair = None def require_capabilities(self, requirements, fatal_failure=False): """Require capabilities of this LinuxSystem. Check that capabilities in |requirements| exist on this system. Raise and exception to skip but not fail the test if said capabilities are not found. Pass |fatal_failure| to cause this error to become a test failure. @param requirements list of CAPABILITY_* defined above. @param fatal_failure bool True iff failures should be fatal. """ to_be_raised = error.TestNAError if fatal_failure: to_be_raised = error.TestFail missing = [cap for cap in requirements if not cap in self.capabilities] if missing: raise to_be_raised('AP on %s is missing required capabilites: %r' % (self.role, missing)) def disable_antennas_except(self, permitted_antennas): """Disable unwanted antennas. Disable all antennas except those specified in |permitted_antennas|. Note that one or more of them may remain disabled if the underlying hardware does not support them. @param permitted_antennas int bitmask specifying antennas that we should attempt to enable. """ for phy in self.phy_list: if not phy.supports_setting_antenna_mask: continue # Determine valid bitmap values based on available antennas. self.iw_runner.set_antenna_bitmap(phy.name, permitted_antennas & phy.avail_tx_antennas, permitted_antennas & phy.avail_rx_antennas) def enable_all_antennas(self): """Enable all antennas on all phys.""" for phy in self.phy_list: if not phy.supports_setting_antenna_mask: continue self.iw_runner.set_antenna_bitmap(phy.name, phy.avail_tx_antennas, phy.avail_rx_antennas) def ping(self, ping_config): """Ping an IP from this system. @param ping_config PingConfig object describing the ping command to run. @return a PingResult object. """ logging.info('Pinging from the %s.', self.role) return self._ping_runner.ping(ping_config)