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Test Info: Errors
- This test failed 70 times in the preceding 30 days. quicksearch this test
- Manifest: toolkit/components/resistfingerprinting/tests/browser/browser.toml
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/**
*/
const emptyPage =
getRootDirectory(gTestPath).replace(
) + "empty.html";
function getImageData(tab, isOffscreen, method) {
const extractCanvas = function (isOffscreen, method) {
const canvas = isOffscreen
? new OffscreenCanvas(3, 1)
: document.createElement("canvas");
const ctx = canvas.getContext("2d");
ctx.fillStyle = "rgb(255, 0, 0)";
ctx.fillRect(0, 0, 1, 1);
ctx.fillStyle = "rgb(0, 255, 0)";
ctx.fillRect(1, 0, 1, 1);
ctx.fillStyle = "rgb(0, 0, 255)";
ctx.fillRect(2, 0, 1, 1);
if (method === "getImageData") {
return ctx.getImageData(0, 0, 3, 1).data.join(",");
} else if (method === "toDataURL") {
return canvas.toDataURL();
} else if (method === "toBlob") {
return new Promise((resolve, reject) => {
if (isOffscreen) {
canvas.convertToBlob().then(resolve, reject);
} else {
canvas.toBlob(resolve, "image/png");
}
}).then(blob => {
const reader = new FileReader();
reader.readAsDataURL(blob);
const { promise, resolve, reject } = Promise.withResolvers();
reader.onload = () => resolve(reader.result);
reader.onerror = reject;
return promise;
});
}
return null;
};
const extractCanvasExpr = `(${extractCanvas.toString()})(${isOffscreen}, "${method}");`;
return SpecialPowers.spawn(
tab.linkedBrowser,
[extractCanvasExpr],
async funccode => content.eval(funccode)
);
}
// Test cases: [isOffscreen, method, true value]
const TEST_CASES = [
// HTMLCanvasElement
[false, "getImageData", null],
[false, "toDataURL", null],
[false, "toBlob", null],
// OffscreenCanvas
[true, "getImageData", null],
[true, "toBlob", null],
];
add_setup(async function setup() {
await SpecialPowers.pushPrefEnv({
set: [
["privacy.resistFingerprinting", false],
["privacy.fingerprintingProtection", false],
],
});
const tab = await BrowserTestUtils.openNewForegroundTab({
gBrowser,
opening: emptyPage,
forceNewProcess: true,
});
for (let i = 0; i < TEST_CASES.length; i++) {
const test_case = TEST_CASES[i];
const [isOffscreen, method] = test_case;
const imageData = await getImageData(tab, isOffscreen, method);
test_case[2] = imageData;
}
BrowserTestUtils.removeTab(tab);
await SpecialPowers.popPrefEnv();
});
async function runTest(permissionGranted, isRFP) {
await SpecialPowers.pushPrefEnv({
set: [
["privacy.resistFingerprinting", isRFP],
["privacy.fingerprintingProtection", !isRFP],
[
"privacy.fingerprintingProtection.overrides",
"-AllTargets,+CanvasRandomization,+CanvasImageExtractionPrompt",
],
],
});
const tab = await BrowserTestUtils.openNewForegroundTab({
gBrowser,
opening: emptyPage,
forceNewProcess: true,
});
if (permissionGranted) {
await SpecialPowers.pushPermissions([
{
type: "canvas",
allow: true,
context: emptyPage,
},
]);
}
for (let i = 0; i < TEST_CASES.length; i++) {
const test_case = TEST_CASES[i];
const [isOffscreen, method, trueValue] = test_case;
const imageData = await getImageData(tab, isOffscreen, method);
const message = `Image data was ${
permissionGranted ? "not " : ""
}randomized for ${method} on ${
isOffscreen ? "OffscreenCanvas" : "HTMLCanvasElement"
}.`;
if (isOffscreen) {
// Offscreen canvas doesn't respect the permission.
continue;
}
permissionGranted
? is(imageData, trueValue, message)
: isnot(imageData, trueValue, message);
}
if (permissionGranted) {
await SpecialPowers.popPermissions();
}
BrowserTestUtils.removeTab(tab);
await SpecialPowers.popPrefEnv();
}
add_task(async function test_rfp_no_permission() {
await runTest(false, true);
});
add_task(async function test_rfp_permission() {
await runTest(true, true);
});
add_task(async function test_fpp_no_permission() {
await runTest(false, false);
});
add_task(async function test_fpp_permission() {
await runTest(true, false);
});