bluetooth: Generate random service uuid and generate random fake adapter.

third_party/WebKit/Source/modules/bluetooth/web_bluetooth_fuzzer/constraints.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Module to get random numbers, strings, etc.
 
    The values returned by the various functions can be replaced in
    templates to generate test cases.
 """
 
+import os
 import random
+import sys
+import uuid
+
+import gatt_aliases
+
+# This file is uploaded next to 'common' to ClusterFuzz so we try to import
+# the necessary modules from there. If we fail then we try the parent directory,
+# where common is usually located when developing locally.
+try:
+    # pylint: disable=E0611
+    from common import utils
+    from common import fuzzy_types
+except ImportError:
+    sys.path.append(os.pardir)

[ortuno, 2016/07/21 21:35:24]

Now the setup.py script copies these files.

+    # pylint: disable=E0611
+    from common import utils
+    from common import fuzzy_types
 
 
-def GetValidUUIDString():
-    """Constructs a valid UUID string.
+# List of services that are included in our fake adapters.

[ortuno, 2016/07/21 21:35:24]

Done.

+FAKE_SERVICES = [
+    'generic_access',
+    'glucose',
+    'heart_rate',
+    'battery_service',
+    'human_interface_device',
+    '000000a0-97e5-4cd7-b9f1-f5a427670c59',  # Error UUID
+    'device_information',
+    '611c954a-263b-4f4a-aab6-01ddb953f985',  # Blacklist
+    '01d7d889-7451-419f-aeb8-d65e7b9277af',  # Request Disconnection
+]
+
+# List of available fake adapters.
+FAKE_ADAPTERS = [
+    'BaseAdapter',
+    'NotPresentAdapter',
+    'NotPoweredAdapter',
+    'EmptyAdapter',
+    'FailStartDiscoveryAdapter',
+    'GlucoseHeartRateAdapter',
+    'UnicodeDeviceAdapter',
+    'MissingServiceHeartRateAdapter',
+    'MissingCharacteristicHeartRateAdapter',
+    'HeartRateAdapter',
+    'TwoHeartRateServicesAdapter',
+    'DisconnectingHeartRateAdapter',
+    'BlacklistTestAdapter',
+    'FailingConnectionsAdapter',
+    'FailingGATTOperationsAdapter',
+    'DelayedServicesDiscoveryAdapter',
+]
+
+
+def _ToJsStr(s):
+    return u'\'{}\''.format(s)
+
+
+def GetFakeAdapter():
+    return _ToJsStr(random.choice(FAKE_ADAPTERS))
+
+
+def _GetFuzzedJsString(s):
+    """Returns a fuzzed string based on |s|.
+
+    Args:
+      s: The base string to fuzz.
+    Returns:
+      A single line string surrounded by quotes.
+    """
+    while True:
+        fuzzed_string = fuzzy_types.FuzzyString(s)
+        try:
+            fuzzed_string = fuzzed_string.decode('utf8')
+        except UnicodeDecodeError:
+            print 'Can\'t decode fuzzed string. Trying again.'
+        else:
+            fuzzed_string = '\\n'.join(fuzzed_string.split())
+            fuzzed_string = fuzzed_string.replace('\'', r'\'')
+            return _ToJsStr(fuzzed_string)
+
+
+def GetServiceUUIDFromFakes():
+    """Returns a random service string from the list of fake services."""
+    return _ToJsStr(random.choice(FAKE_SERVICES))
+
+
+def GetValidServiceAlias():
+    """Returns a valid service alias from the list of services aliases."""
+    return _ToJsStr(random.choice(gatt_aliases.SERVICES))
+
+
+def GetRandomUUID():
+    """Returns a random UUID, a random number or a fuzzed uuid or alias."""
+    roll = random.random()

[ortuno, 2016/07/21 21:35:24]

Done.

+    if roll < 1 / 3:
+        # Random UUID
+        return _ToJsStr(uuid.uuid4())
+    elif roll < 2 / 3:
+        # Random number
+        return utils.UniformExpoInteger(0, sys.maxsize.bit_length() + 1)
+    else:
+        # Fuzzed UUID or alias
+        if random.getrandbits(1):
+            random_uuid = str(uuid.uuid4())
+            return _GetFuzzedJsString(random_uuid)
+        else:
+            alias = random.choice(gatt_aliases.SERVICES)
+            return _GetFuzzedJsString(alias)
+
+
+def GetServiceUUID():
+    """Generates a random Service UUID from a set of functions.
+
+    See GetServiceUUIDFromFakes(), GetValidServiceAlias() and GetRandomUUID()
+    for the different values this function can return.
+
+    This function weights GetServiceUUIDFromFakes() more heavily to increase the
+    probability of generating test pages that can interact with the fake
+    adapters.
 
     Returns:
-      A string representating a valid UUID according to:
-      https://webbluetoothcg.github.io/web-bluetooth/#valid-uuid
+      A string or a number that can be used as a Service UUID by the Web
+      Bluetooth API.
     """
-
-    return '\'{:08x}-{:04x}-{:04x}-{:04x}-{:012x}\''.format(
-        random.getrandbits(32),
-        random.getrandbits(16),
-        random.getrandbits(16),
-        random.getrandbits(16),
-        random.getrandbits(48))
+    roll = random.random()
+    if roll < 0.8:
+        return GetServiceUUIDFromFakes()
+    elif roll < 0.9:
+        return GetValidServiceAlias()
+    else:
+        return GetRandomUUID()
 
 
 def GetRequestDeviceOptions():
     """Returns an object used by navigator.bluetooth.requestDevice."""
     # TODO(ortuno): Randomize the members, number of filters, services, etc.
 
-    return '{filters: [{services: [ %s ]}]}' % GetValidUUIDString()
+    return '{filters: [{services: [ %s ]}]}' % GetServiceUUID()