[Sensors] Allow Sensor API only on secure top-level browsing contexts and add frequency checks

third_party/WebKit/Source/modules/sensor/Sensor.cpp

 // 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.
 
 #include "modules/sensor/Sensor.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "device/generic_sensor/public/interfaces/sensor.mojom-blink.h"
 #include "modules/sensor/SensorErrorEvent.h"
 #include "modules/sensor/SensorPollingStrategy.h"
 #include "modules/sensor/SensorProviderProxy.h"
 #include "modules/sensor/SensorReading.h"
 #include "modules/sensor/SensorReadingEvent.h"
 
 using namespace device::mojom::blink;
 
 namespace blink {
 
-Sensor::Sensor(ExecutionContext* executionContext, const SensorOptions& sensorOptions, SensorType type)
+Sensor::Sensor(ScriptState* scriptState, ExecutionContext* executionContext, const SensorOptions& sensorOptions, ExceptionState& exceptionState, SensorType type)
     : ActiveScriptWrappable(this)
     , ContextLifecycleObserver(executionContext)
     , PageVisibilityObserver(toDocument(executionContext)->page())
     , m_sensorOptions(sensorOptions)
     , m_type(type)
     , m_state(Sensor::SensorState::IDLE)
     , m_storedData()
 {
+    // Check secure context.
+    String errorMessage;
+    if (!executionContext->isSecureContext(errorMessage)) {
+        exceptionState.throwDOMException(SecurityError, errorMessage);
+        return;
+    }
+
+    // Check top-level browsing context.
+    if (!scriptState->domWindow()->frame() || !scriptState->domWindow()->frame()->isMainFrame()) {

[haraken, 2016/09/19 13:09:41]

You need to add '!scriptState->domWindow() ||' as well.

[Mikhail, 2016/09/19 14:18:02]

Done.

+        exceptionState.throwSecurityError("Must be in a top-level browsing context");
+        return;
+    }
+
+    // Check the given frequency value.
+    if (m_sensorOptions.hasFrequency()) {
+        double frequency = m_sensorOptions.frequency();
+        if (frequency <= 0.0) {
+            exceptionState.throwRangeError("Frequency must be positive");

[shalamov, 2016/09/19 13:11:42]

nit: Dot at the end of error message.

[Mikhail, 2016/09/19 14:18:02]

Done.

+            return;
+        }
+        // Cap to 60.0 Hz
+        const double kMaxAllowedFrequency = 60.0;
+        if (frequency > kMaxAllowedFrequency)
+            m_sensorOptions.setFrequency(kMaxAllowedFrequency);
+    }
 }
 
 Sensor::~Sensor() = default;
 
 void Sensor::start(ScriptState* scriptState, ExceptionState& exceptionState)
 {
     if (m_state != Sensor::SensorState::IDLE && m_state != Sensor::SensorState::ERRORED) {
         exceptionState.throwDOMException(InvalidStateError, "Cannot start because SensorState is not idle or errored");
         return;
     }
@@ skipping 224 matching lines @@
 
     if (m_state != Sensor::SensorState::ACTIVE
         || page()->visibilityState() != PageVisibilityStateVisible) {
         m_polling->stopPolling();
     } else {
         m_polling->startPolling();
     }
 }
 
 } // namespace blink