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/* 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";
const extractCanvas = async empty => {
const canvas = new content.OffscreenCanvas(64, 64);
const gl = canvas.getContext("webgl");
if (!gl) {
ok(true, "No webgl context, skipping test.");
return -1;
}
if (!empty) {
gl.disable(gl.DEPTH_TEST);
content.document.body.innerHTML = `
<script id="vs" type="x-shader/x-vertex">
attribute vec2 aVertCoord;
void main(void) {
gl_Position = vec4(aVertCoord, 0.0, 1.0);
}
</script>
<script id="fs1" type="x-shader/x-fragment">
precision mediump float;
void main(void) {
gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
}
</script>
<script id="fs2" type="x-shader/x-fragment">
precision mediump float;
void main(void) {
gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
}
</script>
`;
const draw = (vsId, fsId, vertCoordArr) => {
function createShaderById(gl, id) {
var elem = content.document.getElementById(id);
if (!elem) {
throw new Error(
"Failed to create shader from non-existent id '" + id + "'."
);
}
var src = elem.innerHTML.trim();
var shader;
if (elem.type == "x-shader/x-fragment") {
shader = gl.createShader(gl.FRAGMENT_SHADER);
} else if (elem.type == "x-shader/x-vertex") {
shader = gl.createShader(gl.VERTEX_SHADER);
} else {
throw new Error(
"Bad MIME type for shader '" + id + "': " + elem.type + "."
);
}
gl.shaderSource(shader, src);
gl.compileShader(shader);
return shader;
}
function createProgramByIds(gl, vsId, fsId) {
var vs = createShaderById(gl, vsId);
var fs = createShaderById(gl, fsId);
if (!vs || !fs) {
return null;
}
var prog = gl.createProgram();
gl.attachShader(prog, vs);
gl.attachShader(prog, fs);
gl.linkProgram(prog);
if (!gl.getProgramParameter(prog, gl.LINK_STATUS)) {
var str = "Shader program linking failed:";
str += "\nShader program info log:\n" + gl.getProgramInfoLog(prog);
str += "\n\nVert shader log:\n" + gl.getShaderInfoLog(vs);
str += "\n\nFrag shader log:\n" + gl.getShaderInfoLog(fs);
console.error(str);
return null;
}
return prog;
}
const prog = createProgramByIds(gl, vsId, fsId);
if (!prog) {
ok(false, "Program linking should succeed.");
return;
}
prog.aVertCoord = gl.getAttribLocation(prog, "aVertCoord");
const vertCoordBuff = gl.createBuffer();
gl.bindBuffer(gl.ARRAY_BUFFER, vertCoordBuff);
gl.bufferData(gl.ARRAY_BUFFER, vertCoordArr, gl.STATIC_DRAW);
const indexArr = new Uint16Array([0, 1, 2, 3]);
const indexBuff = gl.createBuffer();
gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexBuff);
gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indexArr, gl.STATIC_DRAW);
gl.useProgram(prog);
gl.enableVertexAttribArray(prog.aVertCoord);
gl.vertexAttribPointer(prog.aVertCoord, 2, gl.FLOAT, false, 0, 0);
gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
};
const vertCoordArr1 = new Float32Array([-1, -1, 1, -1, -1, 1, 1, 1]);
const vertCoordArr2 = new Float32Array([1, -1, 1, -1, -1, 1, 1, 1]);
draw("vs", "fs1", vertCoordArr1);
draw("vs", "fs2", vertCoordArr2);
}
const pixels = new Uint8Array(
gl.drawingBufferWidth * gl.drawingBufferHeight * 4
);
gl.readPixels(
1,
1,
gl.drawingBufferWidth,
gl.drawingBufferHeight,
gl.RGBA,
gl.UNSIGNED_BYTE,
pixels
);
return pixels.join(",");
};
add_task(async function test_placeholder() {
await SpecialPowers.pushPrefEnv({
set: [
["privacy.fingerprintingProtection", true],
[
"privacy.fingerprintingProtection.overrides",
"-AllTargets,+CanvasImageExtractionPrompt",
],
],
});
const tab = await BrowserTestUtils.openNewForegroundTab({
gBrowser,
opening: emptyPage,
});
// Don't draw anything on the canvas
// and read it, we should have a placeholder
const placeholder1 = await SpecialPowers.spawn(
tab.linkedBrowser,
[true],
extractCanvas
);
const placeholder2 = await SpecialPowers.spawn(
tab.linkedBrowser,
[true],
extractCanvas
);
if (placeholder1 === -1 && placeholder2 === -1) {
ok(true, "No webgl context, skipping test.");
BrowserTestUtils.removeTab(tab);
return;
}
ok(
!placeholder1.split(",").every(v => v === "0"),
"Read pixels successfully"
);
ok(
!placeholder2.split(",").every(v => v === "0"),
"Read pixels successfully"
);
isnot(placeholder1, placeholder2, "Both read pixels should be different");
await SpecialPowers.popPrefEnv();
await SpecialPowers.pushPrefEnv({
set: [
["privacy.fingerprintingProtection", true],
[
"privacy.fingerprintingProtection.overrides",
"-AllTargets,+CanvasRandomization",
],
],
});
// Draw something on the canvas
// and read it, we should have a randomized canvas
// and the read pixels should be the same
const randomized1 = await SpecialPowers.spawn(
tab.linkedBrowser,
[false],
extractCanvas
);
const randomized2 = await SpecialPowers.spawn(
tab.linkedBrowser,
[false],
extractCanvas
);
if (randomized1 === -1 && randomized2 === -1) {
ok(true, "No webgl context, skipping test.");
BrowserTestUtils.removeTab(tab);
return;
}
ok(!randomized1.split(",").every(v => v === "0"), "Read pixels successfully");
ok(!randomized2.split(",").every(v => v === "0"), "Read pixels successfully");
is(
randomized1,
randomized2,
"Read pixels should be the same after randomization with no placeholder"
);
await SpecialPowers.popPrefEnv();
BrowserTestUtils.removeTab(tab);
});