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fragattacks/tests/hwsim/test_wnm.py
Jouni Malinen 7f08b2f91d tests: Make WNM Sleep Mode tests more robust 
It was possible for the Action frame used for entring WNM Sleep Mode to
get dropped on the AP side due to it arriving prior to having processed
EAPOL-Key message 4/4 due to a race condition between Data and
Management frame processing paths. Avoid this by waiting for
AP-STA-CONNECTED event from hostapd prior to trying to enter WNM Sleep
Mode. In addition, make the check for the STA flag change more robust by
allowing the wait to be a bit longer with a loop that terminates as soon
as the flag has changed.

Signed-off-by: Jouni Malinen <j@w1.fi>
2015-01-18 15:58:05 +02:00

522 lines
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# WNM tests
# Copyright (c) 2013-2014, Jouni Malinen <j@w1.fi>
#
# This software may be distributed under the terms of the BSD license.
# See README for more details.
import binascii
import struct
import time
import logging
logger = logging.getLogger()
import subprocess
import hostapd
from wlantest import Wlantest
def test_wnm_bss_transition_mgmt(dev, apdev):
"""WNM BSS Transition Management"""
params = { "ssid": "test-wnm",
"time_advertisement": "2",
"time_zone": "EST5",
"wnm_sleep_mode": "1",
"bss_transition": "1" }
hostapd.add_ap(apdev[0]['ifname'], params)
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
dev[0].request("WNM_BSS_QUERY 0")
def test_wnm_disassoc_imminent(dev, apdev):
"""WNM Disassociation Imminent"""
params = { "ssid": "test-wnm",
"time_advertisement": "2",
"time_zone": "EST5",
"wnm_sleep_mode": "1",
"bss_transition": "1" }
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
addr = dev[0].p2p_interface_addr()
hapd.request("DISASSOC_IMMINENT " + addr + " 10")
ev = dev[0].wait_event(["WNM: Disassociation Imminent"])
if ev is None:
raise Exception("Timeout while waiting for disassociation imminent")
if "Disassociation Timer 10" not in ev:
raise Exception("Unexpected disassociation imminent contents")
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-RESULTS"])
if ev is None:
raise Exception("Timeout while waiting for re-connection scan")
def test_wnm_ess_disassoc_imminent(dev, apdev):
"""WNM ESS Disassociation Imminent"""
params = { "ssid": "test-wnm",
"time_advertisement": "2",
"time_zone": "EST5",
"wnm_sleep_mode": "1",
"bss_transition": "1" }
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
addr = dev[0].p2p_interface_addr()
hapd.request("ESS_DISASSOC " + addr + " 10 http://example.com/session-info")
ev = dev[0].wait_event(["ESS-DISASSOC-IMMINENT"])
if ev is None:
raise Exception("Timeout while waiting for ESS disassociation imminent")
if "0 1024 http://example.com/session-info" not in ev:
raise Exception("Unexpected ESS disassociation imminent message contents")
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-RESULTS"])
if ev is None:
raise Exception("Timeout while waiting for re-connection scan")
def test_wnm_ess_disassoc_imminent_pmf(dev, apdev):
"""WNM ESS Disassociation Imminent"""
params = hostapd.wpa2_params("test-wnm-rsn", "12345678")
params["wpa_key_mgmt"] = "WPA-PSK-SHA256";
params["ieee80211w"] = "2";
params["bss_transition"] = "1"
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm-rsn", psk="12345678", ieee80211w="2",
key_mgmt="WPA-PSK-SHA256", proto="WPA2", scan_freq="2412")
addr = dev[0].p2p_interface_addr()
hapd.request("ESS_DISASSOC " + addr + " 10 http://example.com/session-info")
ev = dev[0].wait_event(["ESS-DISASSOC-IMMINENT"])
if ev is None:
raise Exception("Timeout while waiting for ESS disassociation imminent")
if "1 1024 http://example.com/session-info" not in ev:
raise Exception("Unexpected ESS disassociation imminent message contents")
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-RESULTS"])
if ev is None:
raise Exception("Timeout while waiting for re-connection scan")
def check_wnm_sleep_mode_enter_exit(hapd, dev, interval=None, tfs_req=None):
addr = dev.p2p_interface_addr()
sta = hapd.get_sta(addr)
if "[WNM_SLEEP_MODE]" in sta['flags']:
raise Exception("Station unexpectedly in WNM-Sleep Mode")
logger.info("Going to WNM Sleep Mode")
extra = ""
if interval is not None:
extra += " interval=" + str(interval)
if tfs_req:
extra += " tfs_req=" + tfs_req
if "OK" not in dev.request("WNM_SLEEP enter" + extra):
raise Exception("WNM_SLEEP failed")
ok = False
for i in range(20):
time.sleep(0.1)
sta = hapd.get_sta(addr)
if "[WNM_SLEEP_MODE]" in sta['flags']:
ok = True
break
if not ok:
raise Exception("Station failed to enter WNM-Sleep Mode")
logger.info("Waking up from WNM Sleep Mode")
ok = False
dev.request("WNM_SLEEP exit")
for i in range(20):
time.sleep(0.1)
sta = hapd.get_sta(addr)
if "[WNM_SLEEP_MODE]" not in sta['flags']:
ok = True
break
if not ok:
raise Exception("Station failed to exit WNM-Sleep Mode")
def test_wnm_sleep_mode_open(dev, apdev):
"""WNM Sleep Mode - open"""
params = { "ssid": "test-wnm",
"time_advertisement": "2",
"time_zone": "EST5",
"wnm_sleep_mode": "1",
"bss_transition": "1" }
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
ev = hapd.wait_event([ "AP-STA-CONNECTED" ], timeout=5)
if ev is None:
raise Exception("No connection event received from hostapd")
check_wnm_sleep_mode_enter_exit(hapd, dev[0])
check_wnm_sleep_mode_enter_exit(hapd, dev[0], interval=100)
check_wnm_sleep_mode_enter_exit(hapd, dev[0], tfs_req="5b17010001130e110000071122334455661122334455661234")
cmds = [ "foo",
"exit tfs_req=123 interval=10",
"enter tfs_req=qq interval=10" ]
for cmd in cmds:
if "FAIL" not in dev[0].request("WNM_SLEEP " + cmd):
raise Exception("Invalid WNM_SLEEP accepted")
def test_wnm_sleep_mode_rsn(dev, apdev):
"""WNM Sleep Mode - RSN"""
params = hostapd.wpa2_params("test-wnm-rsn", "12345678")
params["time_advertisement"] = "2"
params["time_zone"] = "EST5"
params["wnm_sleep_mode"] = "1"
params["bss_transition"] = "1"
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm-rsn", psk="12345678", scan_freq="2412")
ev = hapd.wait_event([ "AP-STA-CONNECTED" ], timeout=5)
if ev is None:
raise Exception("No connection event received from hostapd")
check_wnm_sleep_mode_enter_exit(hapd, dev[0])
def test_wnm_sleep_mode_rsn_pmf(dev, apdev):
"""WNM Sleep Mode - RSN with PMF"""
wt = Wlantest()
wt.flush()
wt.add_passphrase("12345678")
params = hostapd.wpa2_params("test-wnm-rsn", "12345678")
params["wpa_key_mgmt"] = "WPA-PSK-SHA256";
params["ieee80211w"] = "2";
params["time_advertisement"] = "2"
params["time_zone"] = "EST5"
params["wnm_sleep_mode"] = "1"
params["bss_transition"] = "1"
hostapd.add_ap(apdev[0]['ifname'], params)
hapd = hostapd.Hostapd(apdev[0]['ifname'])
dev[0].connect("test-wnm-rsn", psk="12345678", ieee80211w="2",
key_mgmt="WPA-PSK-SHA256", proto="WPA2", scan_freq="2412")
ev = hapd.wait_event([ "AP-STA-CONNECTED" ], timeout=5)
if ev is None:
raise Exception("No connection event received from hostapd")
check_wnm_sleep_mode_enter_exit(hapd, dev[0])
MGMT_SUBTYPE_ACTION = 13
ACTION_CATEG_WNM = 10
WNM_ACT_BSS_TM_REQ = 7
WNM_ACT_BSS_TM_RESP = 8
def bss_tm_req(dst, src, dialog_token=1, req_mode=0, disassoc_timer=0,
validity_interval=1):
msg = {}
msg['fc'] = MGMT_SUBTYPE_ACTION << 4
msg['da'] = dst
msg['sa'] = src
msg['bssid'] = src
msg['payload'] = struct.pack("<BBBBHB",
ACTION_CATEG_WNM, WNM_ACT_BSS_TM_REQ,
dialog_token, req_mode, disassoc_timer,
validity_interval)
return msg
def rx_bss_tm_resp(hapd, expect_dialog=None, expect_status=None):
for i in range(0, 100):
resp = hapd.mgmt_rx()
if resp is None:
raise Exception("No BSS TM Response received")
if resp['subtype'] == MGMT_SUBTYPE_ACTION:
break
if i == 99:
raise Exception("Not an Action frame")
payload = resp['payload']
if len(payload) < 2 + 3:
raise Exception("Too short payload")
(category, action) = struct.unpack('BB', payload[0:2])
if category != ACTION_CATEG_WNM or action != WNM_ACT_BSS_TM_RESP:
raise Exception("Not a BSS TM Response")
pos = payload[2:]
(dialog, status, bss_term_delay) = struct.unpack('BBB', pos[0:3])
resp['dialog'] = dialog
resp['status'] = status
resp['bss_term_delay'] = bss_term_delay
pos = pos[3:]
if len(pos) >= 6 and status == 0:
resp['target_bssid'] = binascii.hexlify(pos[0:6])
pos = pos[6:]
resp['candidates'] = pos
if expect_dialog is not None and dialog != expect_dialog:
raise Exception("Unexpected dialog token")
if expect_status is not None and status != expect_status:
raise Exception("Unexpected status code %d" % status)
return resp
def expect_ack(hapd):
ev = hapd.wait_event(["MGMT-TX-STATUS"], timeout=5)
if ev is None:
raise Exception("Missing TX status")
if "ok=1" not in ev:
raise Exception("Action frame not acknowledged")
def test_wnm_bss_tm_req(dev, apdev):
"""BSS Transition Management Request"""
params = { "ssid": "test-wnm", "bss_transition": "1" }
hapd = hostapd.add_ap(apdev[0]['ifname'], params)
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
hapd2 = hostapd.add_ap(apdev[1]['ifname'], params)
hapd.set("ext_mgmt_frame_handling", "1")
# truncated BSS TM Request
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x08)
req['payload'] = struct.pack("<BBBBH",
ACTION_CATEG_WNM, WNM_ACT_BSS_TM_REQ,
1, 0, 0)
hapd.mgmt_tx(req)
expect_ack(hapd)
# no disassociation and no candidate list
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
dialog_token=2)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=2, expect_status=1)
# truncated BSS Termination Duration
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x08)
hapd.mgmt_tx(req)
expect_ack(hapd)
# BSS Termination Duration with TSF=0 and Duration=10
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x08, dialog_token=3)
req['payload'] += struct.pack("<BBQH", 4, 10, 0, 10)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=3, expect_status=1)
# truncated Session Information URL
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x10)
hapd.mgmt_tx(req)
expect_ack(hapd)
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x10)
req['payload'] += struct.pack("<BBB", 3, 65, 66)
hapd.mgmt_tx(req)
expect_ack(hapd)
# Session Information URL
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x10, dialog_token=4)
req['payload'] += struct.pack("<BBB", 2, 65, 66)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=4, expect_status=0)
# Preferred Candidate List without any entries
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=5)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=5, expect_status=7)
# Preferred Candidate List with a truncated entry
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01)
req['payload'] += struct.pack("<BB", 52, 1)
hapd.mgmt_tx(req)
expect_ack(hapd)
# Preferred Candidate List with a too short entry
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=6)
req['payload'] += struct.pack("<BB", 52, 0)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=6, expect_status=7)
# Preferred Candidate List with a non-matching entry
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=6)
req['payload'] += struct.pack("<BB6BLBBB", 52, 13,
1, 2, 3, 4, 5, 6,
0, 81, 1, 7)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=6, expect_status=7)
# Preferred Candidate List with a truncated subelement
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=7)
req['payload'] += struct.pack("<BB6BLBBBBB", 52, 13 + 2,
1, 2, 3, 4, 5, 6,
0, 81, 1, 7,
1, 1)
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=7, expect_status=7)
# Preferred Candidate List with lots of invalid optional subelements
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=8)
subelems = struct.pack("<BBHB", 1, 3, 0, 100)
subelems += struct.pack("<BBB", 2, 1, 65)
subelems += struct.pack("<BB", 3, 0)
subelems += struct.pack("<BBQB", 4, 9, 0, 10)
subelems += struct.pack("<BBHLB", 5, 7, 0, 0, 0)
subelems += struct.pack("<BB", 66, 0)
subelems += struct.pack("<BBBBBB", 70, 4, 0, 0, 0, 0)
subelems += struct.pack("<BB", 71, 0)
req['payload'] += struct.pack("<BB6BLBBB", 52, 13 + len(subelems),
1, 2, 3, 4, 5, 6,
0, 81, 1, 7) + subelems
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=8, expect_status=7)
# Preferred Candidate List with lots of valid optional subelements (twice)
req = bss_tm_req(dev[0].p2p_interface_addr(), apdev[0]['bssid'],
req_mode=0x01, dialog_token=8)
# TSF Information
subelems = struct.pack("<BBHH", 1, 4, 0, 100)
# Condensed Country String
subelems += struct.pack("<BBBB", 2, 2, 65, 66)
# BSS Transition Candidate Preference
subelems += struct.pack("<BBB", 3, 1, 100)
# BSS Termination Duration
subelems += struct.pack("<BBQH", 4, 10, 0, 10)
# Bearing
subelems += struct.pack("<BBHLH", 5, 8, 0, 0, 0)
# Measurement Pilot Transmission
subelems += struct.pack("<BBBBB", 66, 3, 0, 0, 0)
# RM Enabled Capabilities
subelems += struct.pack("<BBBBBBB", 70, 5, 0, 0, 0, 0, 0)
# Multiple BSSID
subelems += struct.pack("<BBBB", 71, 2, 0, 0)
req['payload'] += struct.pack("<BB6BLBBB", 52, 13 + len(subelems) * 2,
1, 2, 3, 4, 5, 6,
0, 81, 1, 7) + subelems + subelems
hapd.mgmt_tx(req)
resp = rx_bss_tm_resp(hapd, expect_dialog=8, expect_status=7)
def test_wnm_bss_keep_alive(dev, apdev):
"""WNM keep-alive"""
params = { "ssid": "test-wnm",
"ap_max_inactivity": "1" }
hapd = hostapd.add_ap(apdev[0]['ifname'], params)
addr = dev[0].p2p_interface_addr()
dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
start = hapd.get_sta(addr)
ev = dev[0].wait_event(["CTRL-EVENT-DISCONNECTED"], timeout=2)
if ev is not None:
raise Exception("Unexpected disconnection")
end = hapd.get_sta(addr)
if int(end['rx_packets']) <= int(start['rx_packets']):
raise Exception("No keep-alive packets received")
try:
# Disable client keep-alive so that hostapd will verify connection
# with client poll
dev[0].request("SET no_keep_alive 1")
for i in range(60):
sta = hapd.get_sta(addr)
logger.info("timeout_next=%s rx_packets=%s tx_packets=%s" % (sta['timeout_next'], sta['rx_packets'], sta['tx_packets']))
if i > 1 and sta['timeout_next'] != "NULLFUNC POLL" and int(sta['tx_packets']) > int(end['tx_packets']):
break
ev = dev[0].wait_event(["CTRL-EVENT-DISCONNECTED"], timeout=0.5)
if ev is not None:
raise Exception("Unexpected disconnection (client poll expected)")
finally:
dev[0].request("SET no_keep_alive 0")
if int(sta['tx_packets']) <= int(end['tx_packets']):
raise Exception("No client poll packet seen")
def test_wnm_bss_tm(dev, apdev):
"""WNM BSS Transition Management"""
try:
hapd = None
hapd2 = None
params = { "ssid": "test-wnm",
"country_code": "FI",
"ieee80211d": "1",
"hw_mode": "g",
"channel": "1",
"bss_transition": "1" }
hapd = hostapd.add_ap(apdev[0]['ifname'], params)
id = dev[0].connect("test-wnm", key_mgmt="NONE", scan_freq="2412")
dev[0].set_network(id, "scan_freq", "")
params = { "ssid": "test-wnm",
"country_code": "FI",
"ieee80211d": "1",
"hw_mode": "a",
"channel": "36",
"bss_transition": "1" }
hapd2 = hostapd.add_ap(apdev[1]['ifname'], params)
addr = dev[0].p2p_interface_addr()
dev[0].dump_monitor()
logger.info("No neighbor list entries")
if "OK" not in hapd.request("BSS_TM_REQ " + addr):
raise Exception("BSS_TM_REQ command failed")
ev = hapd.wait_event(['BSS-TM-RESP'], timeout=10)
if ev is None:
raise Exception("No BSS Transition Management Response")
if addr not in ev:
raise Exception("Unexpected BSS Transition Management Response address")
if "status_code=0" in ev:
raise Exception("BSS transition accepted unexpectedly")
dev[0].dump_monitor()
logger.info("Neighbor list entry, but not claimed as Preferred Candidate List")
if "OK" not in hapd.request("BSS_TM_REQ " + addr + " neighbor=11:22:33:44:55:66,0x0000,81,3,7"):
raise Exception("BSS_TM_REQ command failed")
ev = hapd.wait_event(['BSS-TM-RESP'], timeout=10)
if ev is None:
raise Exception("No BSS Transition Management Response")
if "status_code=0" in ev:
raise Exception("BSS transition accepted unexpectedly")
dev[0].dump_monitor()
logger.info("Preferred Candidate List (no matching neighbor) without Disassociation Imminent")
if "OK" not in hapd.request("BSS_TM_REQ " + addr + " pref=1 neighbor=11:22:33:44:55:66,0x0000,81,3,7,0301ff neighbor=22:33:44:55:66:77,0x0000,1,36,7 neighbor=00:11:22:33:44:55,0x0000,81,4,7,03010a"):
raise Exception("BSS_TM_REQ command failed")
ev = hapd.wait_event(['BSS-TM-RESP'], timeout=10)
if ev is None:
raise Exception("No BSS Transition Management Response")
if "status_code=0" in ev:
raise Exception("BSS transition accepted unexpectedly")
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-STARTED"], timeout=5)
if ev is None:
raise Exception("No scan started")
dev[0].dump_monitor()
logger.info("Preferred Candidate List (matching neighbor for another BSS) without Disassociation Imminent")
if "OK" not in hapd.request("BSS_TM_REQ " + addr + " pref=1 abridged=1 valid_int=255 neighbor=" + apdev[1]['bssid'] + ",0x0000,115,36,7,0301ff"):
raise Exception("BSS_TM_REQ command failed")
ev = hapd.wait_event(['BSS-TM-RESP'], timeout=10)
if ev is None:
raise Exception("No BSS Transition Management Response")
if "status_code=0" not in ev:
raise Exception("BSS transition request was not accepted: " + ev)
if "target_bssid=" + apdev[1]['bssid'] not in ev:
raise Exception("Unexpected target BSS: " + ev)
dev[0].wait_connected(timeout=15, error="No reassociation seen")
if apdev[1]['bssid'] not in ev:
raise Exception("Unexpected reassociation target: " + ev)
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-STARTED"], timeout=0.1)
if ev is not None:
raise Exception("Unexpected scan started")
dev[0].dump_monitor()
logger.info("Preferred Candidate List with two matches, no roam needed")
if "OK" not in hapd2.request("BSS_TM_REQ " + addr + " pref=1 abridged=1 valid_int=255 neighbor=" + apdev[0]['bssid'] + ",0x0000,81,1,7,030101 neighbor=" + apdev[1]['bssid'] + ",0x0000,115,36,7,0301ff"):
raise Exception("BSS_TM_REQ command failed")
ev = hapd2.wait_event(['BSS-TM-RESP'], timeout=10)
if ev is None:
raise Exception("No BSS Transition Management Response")
if "status_code=0" not in ev:
raise Exception("BSS transition request was not accepted: " + ev)
if "target_bssid=" + apdev[1]['bssid'] not in ev:
raise Exception("Unexpected target BSS: " + ev)
ev = dev[0].wait_event(["CTRL-EVENT-SCAN-STARTED"], timeout=0.1)
if ev is not None:
raise Exception("Unexpected scan started")
ev = dev[0].wait_event(["CTRL-EVENT-CONNECTED"], timeout=0.5)
if ev is not None:
raise Exception("Unexpected reassociation");
finally:
dev[0].request("DISCONNECT")
if hapd:
hapd.request("DISABLE")
if hapd2:
hapd2.request("DISABLE")
subprocess.call(['iw', 'reg', 'set', '00'])
dev[0].flush_scan_cache()
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