Bug 1919090: Flatten ICE foundations info. r=tjr

Differential Revision: https://phabricator.services.mozilla.com/D222345

toolkit/components/resistfingerprinting/UserCharacteristicsPageService.sys.mjs

@@ -338,7 +338,8 @@ export class UserCharacteristicsPageService {
         "jsErrors",
         "pointerType",
         "anyPointerType",
-        "iceFoundations",
+        "iceSd",
+        "iceOrder",
         "motionDecimals",
         "orientationDecimals",
         "orientationabsDecimals",

toolkit/components/resistfingerprinting/content/usercharacteristics.js

@@ -1017,12 +1017,11 @@ async function populateICEFoundations() {
 
     // With no other peers, we wouldn't get prflx candidates.
     // Relay type of candidates require a turn server.
-    // So, we'll only get host and srflx candidates.
+    // srflx candidates require a stun server.
+    // So, we'll only get host candidates.
     const result = {
-      hostLatencies: [],
-      hostFoundations: [],
-      srflxLatencies: [],
-      srflxFoundations: [],
+      latencies: [],
+      foundations: [],
     };
 
     let lastTime;
@@ -1033,14 +1032,12 @@ async function populateICEFoundations() {
       return latency;
     }
 
-    const pc = new RTCPeerConnection({
-      iceServers: [{ urls: ["stun:stun.l.google.com:19302"] }],
-    });
+    const pc = new RTCPeerConnection();
     pc.onicecandidate = e => {
       const latency = calculateLatency();
       if (e.candidate && e.candidate.candidate !== "") {
-        result[e.candidate.type + "Latencies"].push(latency);
-        result[e.candidate.type + "Foundations"].push(e.candidate.foundation);
+        result.latencies.push(latency);
+        result.foundations.push(e.candidate.foundation);
       }
     };
     pc.onicegatheringstatechange = () => {
@@ -1063,51 +1060,33 @@ async function populateICEFoundations() {
 
   // Run get candidates multiple times to see if foundation order changes
   // and calculate standard deviation of latencies
-  const allLatencies = {
-    srflx: [],
-    host: [],
-  };
-  const allFoundations = {
-    srflx: {},
-    host: {},
-  };
+  const latencies = [];
+  const foundations = {};
   for (let i = 0; i < 10; i++) {
     const result = await getFoundationsAndLatencies();
-    const hostFoundations = result.hostFoundations.join("");
-    const srflxFoundations = result.srflxFoundations.join("");
 
-    allLatencies.host.push(result.hostLatencies);
-    allLatencies.srflx.push(result.srflxLatencies);
+    latencies.push(result.latencies);
 
+    const hostFoundations = result.foundations.join("");
     if (hostFoundations) {
-      allFoundations.host[hostFoundations] =
-        (allFoundations.host[hostFoundations] ?? 0) + 1;
-    }
-    if (srflxFoundations) {
-      allFoundations.srflx[srflxFoundations] =
-        (allFoundations.srflx[srflxFoundations] ?? 0) + 1;
+      foundations[hostFoundations] = (foundations[hostFoundations] ?? 0) + 1;
     }
   }
 
-  const sdLatencies = {
-    host: [],
-    srflx: [],
-  };
-  for (let i = 0; i < (allLatencies.host?.[0]?.length ?? 0); i++) {
-    sdLatencies.host.push(standardDeviation(allLatencies.host.map(a => a[i])));
-  }
-  for (let i = 0; i < (allLatencies.srflx?.[0]?.length ?? 0); i++) {
-    sdLatencies.srflx.push(
-      standardDeviation(allLatencies.srflx.map(a => a[i]))
-    );
+  const sdLatencies = [];
+  for (let i = 0; i < (latencies?.[0]?.length ?? 0); i++) {
+    sdLatencies.push(standardDeviation(latencies.map(a => a[i])));
   }
 
+  const sd =
+    sdLatencies.length > 1
+      ? (sdLatencies.reduce((acc, val) => acc + val, 0) / sdLatencies.length) *
+        1000
+      : 0;
+
   return {
-    iceFoundations: JSON.stringify({
-      uniqueHostOrder: Object.keys(allFoundations.host).length,
-      uniqueSrflxOrder: Object.keys(allFoundations.srflx).length,
-      sdLatencies,
-    }),
+    iceSd: sd,
+    iceOrder: Object.keys(foundations).length,
   };
 }
 

toolkit/components/resistfingerprinting/metrics.yaml

@@ -2587,25 +2587,41 @@ characteristics:
     data_sensitivity:
       - technical
 
-  ice_foundations:
-    type: text
+  ice_order:
+    type: quantity
+    unit: int
     description: >
-      Unique ICE foundations occurance count and the
-      standard deviation of latencies
+      Unique ICE foundations occurrence count
     lifetime: application
     send_in_pings:
       - user-characteristics
     notification_emails:
       - tom@mozilla.com
     bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1902003
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1919090
     data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1902003#c2
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1919090#c4
     expires: never
     data_sensitivity:
-      # Text metrics are _required_ to be web_activity or highly_sensitive, so even though this
-      # is more like 'technical' (per the Data Review), I'm marking highly sensitive.
-      - highly_sensitive
+      - technical
+
+  ice_sd:
+    type: quantity
+    unit: int
+    description: >
+      ICE foundation discovery latency standard deviation sum multiplied by 1000
+    lifetime: application
+    send_in_pings:
+      - user-characteristics
+    notification_emails:
+      - tom@mozilla.com
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1919090
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1919090#c4
+    expires: never
+    data_sensitivity:
+      - technical
 
   pointer_height:
     type: quantity