tests: Add test cases for automatic channel selection

This extends the Hostapd class to support monitor interface events and
STATUS command similarly to the WpaSupplicant class so that internal
hostapd state can be verified in more detail.

Signed-hostap: Jouni Malinen <j@w1.fi>

tests/hwsim/hostapd.py

@@ -46,6 +46,8 @@ class Hostapd:
     def __init__(self, ifname):
         self.ifname = ifname
         self.ctrl = wpaspy.Ctrl(os.path.join(hapd_ctrl, ifname))
+        self.mon = wpaspy.Ctrl(os.path.join(hapd_ctrl, ifname))
+        self.mon.attach()
 
     def request(self, cmd):
         logger.debug(self.ifname + ": CTRL: " + cmd)
@@ -109,6 +111,39 @@ class Hostapd:
         if not "OK" in self.ctrl.request("ENABLE"):
             raise Exception("Failed to disable hostapd interface " + self.ifname)
 
+    def dump_monitor(self):
+        while self.mon.pending():
+            ev = self.mon.recv()
+            logger.debug(self.ifname + ": " + ev)
+
+    def wait_event(self, events, timeout):
+        count = 0
+        while count < timeout * 10:
+            count = count + 1
+            time.sleep(0.1)
+            while self.mon.pending():
+                ev = self.mon.recv()
+                logger.debug(self.ifname + ": " + ev)
+                for event in events:
+                    if event in ev:
+                        return ev
+        return None
+
+    def get_status(self):
+        res = self.request("STATUS")
+        lines = res.splitlines()
+        vals = dict()
+        for l in lines:
+            [name,value] = l.split('=', 1)
+            vals[name] = value
+        return vals
+
+    def get_status_field(self, field):
+        vals = self.get_status()
+        if field in vals:
+            return vals[field]
+        return None
+
 def add_ap(ifname, params):
         logger.info("Starting AP " + ifname)
         hapd_global = HostapdGlobal()
@@ -133,6 +168,7 @@ def add_ap(ifname, params):
             else:
                 hapd.set(f, v)
         hapd.enable()
+        return hapd
 
 def add_bss(phy, ifname, confname, ignore_error=False):
     logger.info("Starting BSS phy=" + phy + " ifname=" + ifname)

tests/hwsim/multi-bss-acs.conf

@@ -0,0 +1,28 @@
+driver=nl80211
+
+hw_mode=g
+channel=0
+ieee80211n=1
+
+interface=wlan3
+ctrl_interface=/var/run/hostapd
+
+ssid=bss-1
+
+bss=wlan3-2
+bssid=02:00:00:00:03:01
+ctrl_interface=/var/run/hostapd
+ssid=bss-2
+wpa=2
+wpa_key_mgmt=WPA-PSK
+rsn_pairwise=CCMP
+wpa_passphrase=12345678
+
+bss=wlan3-3
+bssid=02:00:00:00:03:02
+ctrl_interface=/var/run/hostapd
+ssid=bss-3
+wpa=1
+wpa_key_mgmt=WPA-PSK
+rsn_pairwise=TKIP
+wpa_passphrase=qwertyuiop

tests/hwsim/test_ap_acs.py

@@ -0,0 +1,68 @@
+#!/usr/bin/python
+#
+# Test cases for automatic channel selection with hostapd
+# Copyright (c) 2013, Jouni Malinen <j@w1.fi>
+#
+# This software may be distributed under the terms of the BSD license.
+# See README for more details.
+
+import logging
+logger = logging.getLogger()
+
+import hostapd
+
+def wait_acs(hapd):
+    ev = hapd.wait_event(["ACS-STARTED", "ACS-COMPLETED", "ACS-FAILED",
+                          "AP-ENABLED"], timeout=5)
+    if not ev:
+        raise Exception("ACS start timed out")
+    if "ACS-STARTED" not in ev:
+        raise Exception("Unexpected ACS event")
+
+    state = hapd.get_status_field("state")
+    if state != "ACS":
+        raise Exception("Unexpected interface state")
+
+    ev = hapd.wait_event(["ACS-COMPLETED", "ACS-FAILED", "AP-ENABLED"],
+                         timeout=20)
+    if not ev:
+        raise Exception("ACS timed out")
+    if "ACS-COMPLETED" not in ev:
+        raise Exception("Unexpected ACS event")
+
+    ev = hapd.wait_event(["AP-ENABLED"], timeout=5)
+    if not ev:
+        raise Exception("AP setup timed out")
+
+    state = hapd.get_status_field("state")
+    if state != "ENABLED":
+        raise Exception("Unexpected interface state")
+
+def test_ap_acs(dev, apdev):
+    """Automatic channel selection"""
+    params = hostapd.wpa2_params(ssid="test-acs", passphrase="12345678")
+    params['channel'] = '0'
+    hapd = hostapd.add_ap(apdev[0]['ifname'], params)
+    wait_acs(hapd)
+
+    freq = hapd.get_status_field("freq")
+    if int(freq) < 2400:
+        raise Exception("Unexpected frequency")
+
+    dev[0].connect("test-acs", psk="12345678", scan_freq=freq)
+
+def test_ap_multi_bss_acs(dev, apdev):
+    """hostapd start with a multi-BSS configuration file using ACS"""
+    ifname = apdev[0]['ifname']
+    hostapd.add_iface(ifname, 'multi-bss-acs.conf')
+    hapd = hostapd.Hostapd(ifname)
+    hapd.enable()
+    wait_acs(hapd)
+
+    freq = hapd.get_status_field("freq")
+    if int(freq) < 2400:
+        raise Exception("Unexpected frequency")
+
+    dev[0].connect("bss-1", key_mgmt="NONE", scan_freq=freq)
+    dev[1].connect("bss-2", psk="12345678", scan_freq=freq)
+    dev[2].connect("bss-3", psk="qwertyuiop", scan_freq=freq)