auto-t: Add frame fuzzing test

Add a test to validate a crash found by Alex Radocea when sending
a fuzzed beacon frame.

Co-authored-by: Alex Radocea <alex@supernetworks.org>

autotests/testFrameFuzzing/fake_ap.py

@@ -0,0 +1,72 @@
+import unittest
+import sys
+import sys
+import os
+from scapy.layers.dot11 import *
+from scapy.arch import str2mac, get_if_raw_hwaddr
+from time import time, sleep
+from threading import Thread
+
+def if_hwaddr(iff):
+    return str2mac(get_if_raw_hwaddr(iff)[1])
+
+def config_mon(iface, channel):
+  """set the interface in monitor mode and then change channel using iw"""
+  os.system("ip link set dev %s down" % iface)
+  os.system("iw dev %s set type monitor" % iface)
+  os.system("ip link set dev %s up" % iface)
+  os.system("iw dev %s set channel %d" % (iface, channel))
+
+class AP:
+    def __init__(self, ssid, psk, mac=None, mode="stdio", iface="wlan0", channel=1):
+        self.channel = channel
+        self.iface = iface
+        self.mode = mode
+        if self.mode == "iface":
+            if not mac:
+              mac = if_hwaddr(iface)
+            config_mon(iface, channel)
+        if not mac:
+          raise Exception("Need a mac")
+        else:
+          self.mac = mac
+        self.boottime = time()
+
+    def get_radiotap_header(self):
+        return RadioTap()
+
+    def dot11_beacon(self, contents):
+        evil_packet = (
+            self.get_radiotap_header()
+            / Dot11(
+                subtype=8, addr1="ff:ff:ff:ff:ff:ff", addr2=self.mac, addr3=self.mac
+            )
+            / Dot11Beacon(cap=0x3101)
+            / contents
+        )
+        self.sendp(evil_packet)
+
+    def run(self, contents):
+        interval = 0.05
+        num_beacons = 100
+
+        while num_beacons:
+            self.dot11_beacon(contents)
+            sleep(interval)
+            num_beacons -= 1
+
+    def start(self, contents):
+       self.thread = Thread(target=self.run, args=(contents,))
+       self.thread.start()
+
+    def stop(self):
+       self.thread.join()
+
+    def sendp(self, packet, verbose=False):
+        if self.mode == "stdio":
+            x = packet.build()
+            sys.stdout.buffer.write(struct.pack("<L", len(x)) + x)
+            sys.stdout.buffer.flush()
+            return
+        assert self.mode == "iface"
+        sendp(packet, iface=self.iface, verbose=False)

autotests/testFrameFuzzing/hw.conf

@@ -0,0 +1,7 @@
+[SETUP]
+num_radios=2
+start_iwd=0
+hwsim_medium=yes
+
+[rad1]
+reserve=true

autotests/testFrameFuzzing/test_frame_fuzzing.py

@@ -0,0 +1,37 @@
+#! /usr/bin/python3
+
+import unittest
+import sys
+import sys
+import os
+from fake_ap import AP
+
+sys.path.append('../util')
+from iwd import IWD
+
+# Probe frame that causes IWD to crash
+beacon=b'\xdd\nPo\x9a\t\x0e\x00\x00\x19\x10\x00\xdd/Po\x9a\t\x0c\x02\x00\x00\xdd\x05\x03\x03\x03Po\x9a\x10\x00\x0b\x05\x0e\x00\x00\x00\x00\x0b\x05\x00\x00\x00\xdd\x05\x00\x03\x03\x03\x03\x00\x00\x00\xdd\x05\x03\x03\x03\x03\x03'
+
+class Test(unittest.TestCase):
+    def test_beacon_crash(self):
+        wd = IWD(True)
+
+        devs = wd.list_devices()
+
+        self.assertEqual(len(devs), 1)
+
+        devs[0].autoconnect = True
+
+        os.system("iw phy rad1 interface add wlan1 type managed")
+
+        ap = AP("evilAP", "password1234", mode="iface", iface="wlan1", channel=4)
+        ap.start(beacon)
+
+        condition = "obj.scanning == True"
+        wd.wait_for_object_condition(devs[0], condition)
+
+        condition = "obj.scanning == False"
+        wd.wait_for_object_condition(devs[0], condition)
+
+if __name__ == '__main__':
+    unittest.main(exit=True)