tests: Add out-of-memory loop tests for hostapd startup

These test cases run hostapd interface setup multiple times with
TEST_ALLOC_FAIL commands triggering memory allocation failures one by
one at each possible location in the setup sequence. Effectively, these
test cases will hit most error paths for memory allocation issue cases
(i.e., only the cases requiring more than one allocation failure in a
sequence are not covered).

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

tests/hwsim/test_hostapd_oom.py

@@ -0,0 +1,51 @@
+# hostapd and out-of-memory error paths
+# Copyright (c) 2015, Jouni Malinen
+#
+# This software may be distributed under the terms of the BSD license.
+# See README for more details.
+
+import logging
+logger = logging.getLogger()
+
+import hostapd
+from utils import HwsimSkip
+
+def hostapd_oom_loop(apdev, params):
+    hapd = hostapd.add_ap(apdev[0]['ifname'], { "ssid": "ctrl" })
+    hapd_global = hostapd.HostapdGlobal()
+
+    count = 0
+    for i in range(1, 1000):
+        if "OK" not in hapd.request("TEST_ALLOC_FAIL %d:main" % i):
+            raise HwsimSkip("TEST_ALLOC_FAIL not supported")
+        try:
+            hostapd.add_ap(apdev[1]['ifname'], params)
+            logger.info("Iteration %d - success" % i)
+            hapd_global.remove(apdev[1]['ifname'])
+
+            state = hapd.request('GET_ALLOC_FAIL')
+            logger.info("GET_ALLOC_FAIL: " + state)
+            hapd.request("TEST_ALLOC_FAIL 0:")
+            if i < 3:
+                raise Exception("AP setup succeeded during out-of-memory")
+            if not state.startswith('0:'):
+                count += 1
+                if count == 5:
+                    break
+        except Exception, e:
+            logger.info("Iteration %d - %s" % (i, str(e)))
+
+def test_hostapd_oom_open(dev, apdev):
+    """hostapd failing to setup open mode due to OOM"""
+    params = { "ssid": "open" }
+    hostapd_oom_loop(apdev, params)
+
+def test_hostapd_oom_wpa2_psk(dev, apdev):
+    """hostapd failing to setup WPA2-PSK mode due to OOM"""
+    params = hostapd.wpa2_params(ssid="test", passphrase="12345678")
+    hostapd_oom_loop(apdev, params)
+
+def test_hostapd_oom_wpa2_eap(dev, apdev):
+    """hostapd failing to setup WPA2-EAP mode due to OOM"""
+    params = hostapd.wpa2_eap_params(ssid="test")
+    hostapd_oom_loop(apdev, params)