Bug 1904964: Collect audio device information lighter. r=media-playback-reviewers,padenot

Differential Revision: https://phabricator.services.mozilla.com/D215031

dom/media/autoplay/AutoplayPolicy.cpp

@@ -114,6 +114,12 @@ static bool IsWindowAllowedToPlayByTraits(nsPIDOMWindowInner* aWindow) {
     return true;
   }
 
+  if (currentDoc->GetPrincipal()->Equals(
+          nsContentUtils::GetFingerprintingProtectionPrincipal())) {
+    AUTOPLAY_LOG("Allow autoplay as in fingerprinting protection document.");
+    return true;
+  }
+
   return false;
 }
 

toolkit/components/resistfingerprinting/UserCharacteristicsPageService.sys.mjs

@@ -424,6 +424,9 @@ export class UserCharacteristicsPageService {
         "oscpu",
         "pdfViewer",
         "platform",
+        "audioFrames",
+        "audioRate",
+        "audioChannels",
       ],
     };
 

toolkit/components/resistfingerprinting/content/usercharacteristics.js

@@ -1182,6 +1182,22 @@ async function populateMathML() {
   }, {});
 }
 
+async function populateAudioDeviceProperties() {
+  const ctx = new AudioContext();
+  await ctx.resume();
+
+  // Give firefox some time to calculate latency
+  await new Promise(resolve => setTimeout(resolve, 2000));
+
+  // All the other properties (min/max decibels, smoothingTimeConstant,
+  // fftSize, frequencyBinCount, baseLatency) are hardcoded.
+  return {
+    audioFrames: ctx.outputLatency * ctx.sampleRate,
+    audioRate: ctx.sampleRate,
+    audioChannels: ctx.destination.maxChannelCount,
+  };
+}
+
 // A helper function to generate an array of asynchronous functions to populate
 // canvases using both software and hardware rendering.
 function getCanvasSources() {
@@ -1252,6 +1268,7 @@ async function startPopulating() {
     populateMathML,
     populateCSSQueries,
     populateNavigatorProperties,
+    populateAudioDeviceProperties,
   ];
   // Catches errors in promise-creating functions. E.g. if populateVoiceList
   // throws an error before returning any of its `key: (Promise<any> | any)`

toolkit/components/resistfingerprinting/metrics.yaml

@@ -2028,10 +2028,11 @@ characteristics:
       # is more like 'technical' (per the Data Review), I'm marking highly sensitive.
       - highly_sensitive
 
-  audio_devices:
-    type: text
+  audio_frames:
+    type: quantity
+    unit: int
     description: >
-      A JSON object containing sample rate and max channel count of every audio device, and output latency of default device
+      Audio frames
     lifetime: application
     send_in_pings:
       - user-characteristics
@@ -2044,7 +2045,45 @@ characteristics:
       - https://bugzilla.mozilla.org/show_bug.cgi?id=1896490#c3
     expires: never
     data_sensitivity:
-      - highly_sensitive
+      - technical
+
+  audio_rate:
+    type: quantity
+    unit: int
+    description: >
+      Audio sampling rate
+    lifetime: application
+    send_in_pings:
+      - user-characteristics
+    notification_emails:
+      - tom@mozilla.com
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1879151
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1896490
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1896490#c3
+    expires: never
+    data_sensitivity:
+      - technical
+
+  audio_channels:
+    type: quantity
+    unit: int
+    description: >
+      Audio sampling rate
+    lifetime: application
+    send_in_pings:
+      - user-characteristics
+    notification_emails:
+      - tom@mozilla.com
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1879151
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1896490
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1896490#c3
+    expires: never
+    data_sensitivity:
+      - technical
 
   languages:
     type: string

toolkit/components/resistfingerprinting/nsUserCharacteristics.cpp

@@ -46,8 +46,6 @@
 #include "mozilla/dom/MediaDeviceInfoBinding.h"
 #include "mozilla/MozPromise.h"
 #include "nsThreadUtils.h"
-#include "CubebDeviceEnumerator.h"
-#include "mozilla/media/MediaUtils.h"
 #include "mozilla/dom/Navigator.h"
 #include "nsIGSettingsService.h"
 #include "nsITimer.h"
@@ -481,74 +479,6 @@ RefPtr<PopulatePromise> PopulateMediaDevices() {
   return populatePromise;
 }
 
-RefPtr<PopulatePromise> PopulateAudioDeviceProperties() {
-  RefPtr<PopulatePromise> populatePromise = new PopulatePromise(__func__);
-
-  NS_DispatchBackgroundTask(
-      NS_NewRunnableFunction("PopulateAudioDeviceProperties", [=]() {
-        RefPtr<CubebDeviceEnumerator> enumerator =
-            CubebDeviceEnumerator::GetInstance();
-        RefPtr<const CubebDeviceEnumerator::AudioDeviceSet> devices;
-
-        nsCString output = "{"_ns;
-
-        nsCString list = "["_ns;
-        devices = enumerator->EnumerateAudioInputDevices();
-        for (const auto& deviceInfo : *devices) {
-          uint32_t maxChannels;
-          deviceInfo->GetMaxChannels(&maxChannels);
-
-          list.AppendPrintf(R"({"rate":%d,"channels":%d)",
-                            deviceInfo->DefaultRate(), maxChannels);
-          if (deviceInfo->Preferred()) {
-            list.Append(",\"default\":1");
-          }
-          list.Append("}");
-
-          if (&deviceInfo != &devices->LastElement()) {
-            list.Append(',');
-          }
-        }
-        list.Append(']');
-
-        output.AppendPrintf(R"("devices":%s,)", list.get());
-
-        double inputMean, inputStdDev, outputMean, outputStdDev;
-        CubebUtils::EstimatedLatencyDefaultDevices(&inputMean, &inputStdDev,
-                                                   CubebUtils::Side::Input);
-        CubebUtils::EstimatedLatencyDefaultDevices(&outputMean, &outputStdDev,
-                                                   CubebUtils::Side::Output);
-
-        cubeb_stream_params output_params;
-        output_params.format = CUBEB_SAMPLE_FLOAT32NE;
-        output_params.rate = CubebUtils::PreferredSampleRate(false);
-        output_params.channels = 2;
-        output_params.layout = CUBEB_LAYOUT_UNDEFINED;
-        output_params.prefs =
-            CubebUtils::GetDefaultStreamPrefs(CUBEB_DEVICE_TYPE_OUTPUT);
-
-        uint32_t latencyFrames =
-            CubebUtils::GetCubebMTGLatencyInFrames(&output_params);
-        RefPtr<AudioDeviceInfo> defaultOutputDevice =
-            enumerator->DefaultDevice(CubebDeviceEnumerator::Side::OUTPUT);
-        output.AppendPrintf(
-            R"("latency":[%f,%f,%f,%f],"latFrames":%d,"rate":%u,"channels":%u)",
-            inputMean, inputStdDev, outputMean, outputStdDev, latencyFrames,
-            defaultOutputDevice->DefaultRate(),
-            defaultOutputDevice->MaxChannels());
-
-        output.Append("}");
-
-        glean::characteristics::audio_devices.Set(output);
-
-        NS_DispatchToMainThread(NS_NewRunnableFunction(
-            "PopulateAudioDeviceProperties",
-            [=]() { populatePromise->Resolve(void_t(), __func__); }));
-      }));
-
-  return populatePromise;
-}
-
 void PopulateLanguages() {
   // All navigator.languages, navigator.language, and Accept-Languages header
   // use Navigator::GetAcceptLanguages to create a language list. It is
@@ -957,7 +887,6 @@ void nsUserCharacteristics::PopulateDataAndEventuallySubmit(
     // ------------------------------------------------------------------------
 
     promises.AppendElement(PopulateMediaDevices());
-    promises.AppendElement(PopulateAudioDeviceProperties());
     promises.AppendElement(PopulateTimeZone());
     promises.AppendElement(TimoutPromise(PopulatePointerInfo(), 5 * 60 * 1000,
                                          "PopulatePointerInfo"_ns));