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mirror of https://github.com/kkapsner/CanvasBlocker synced 2024-12-22 21:00:23 +01:00
2017-11-24 17:06:43 +01:00

96 lines
2.9 KiB
JavaScript

/* eslint no-console: off */
(function(){
"use strict";
function show(container, url){
var display = container.querySelector(".display");
display.src = url;
display.title = url;
var buffer = new TextEncoder("utf-8").encode(url);
crypto.subtle.digest("SHA-256", buffer).then(function(hash){
var chunks = [];
(new Uint32Array(hash)).forEach(function(num){
chunks.push(num.toString(16));
});
container.querySelector(".hash").textContent = chunks.map(function(chunk){
return "0".repeat(8 - chunk.length) + chunk;
}).join("");
});
}
if (location.search !== "?notInitial"){
try {show(document.getElementById("top"), topTest());}
catch (e){console.error(e);}
try {show(document.getElementById("iframe"), iframeTest(document.querySelector("#iframe iframe")));}
catch (e){console.error(e);}
try {show(document.getElementById("iframe2"), iframeTest(document.querySelector("#iframe2 iframe")));}
catch (e){console.error(e);}
try {show(document.getElementById("iframe3"), iframeTest(document.querySelector("#iframe3 iframe")));}
catch (e){console.error(e);}
}
document.querySelector("#top button").addEventListener("click", function(){
show(document.getElementById("top"), topTest());
});
document.querySelector("#iframe button").addEventListener("click", function(){
show(document.getElementById("iframe"), iframeTest(document.querySelector("#iframe iframe")));
});
document.querySelector("#iframe2 button").addEventListener("click", function(){
show(document.getElementById("iframe2"), iframeTest(document.querySelector("#iframe2 iframe")));
});
document.querySelector("#iframe3 button").addEventListener("click", function(){
show(document.getElementById("iframe3"), iframeTest(document.querySelector("#iframe3 iframe")));
});
}());
function draw(canvas){
"use strict";
canvas.setAttribute("width", 220);
canvas.setAttribute("height", 30);
var fp_text = "BrowserLeaks,com <canvas> 10";
var ctx = canvas.getContext("2d");
ctx.textBaseline = "top";
ctx.font = "14px 'Arial'";
ctx.textBaseline = "alphabetic";
ctx.fillStyle = "#f60";
ctx.fillRect(125, 1, 62, 20);
ctx.fillStyle = "#069";
ctx.fillText(fp_text, 2, 15);
ctx.fillStyle = "rgba(102, 204, 0, 07)";
ctx.fillText(fp_text, 4, 17);
return ctx;
}
function topTest(){
"use strict";
// create window canvas
var canvas = document.createElement("canvas");
// draw image in window canvas
draw(canvas);
return canvas.toDataURL();
}
function iframeTest(iframe){
"use strict";
// create window canvas
var canvas = document.createElement("canvas");
// draw image in window canvas
draw(canvas);
// create iframe canvas and ctx
var iframe_canvas = iframe.contentDocument.createElement("canvas");
iframe_canvas.setAttribute("width", 220);
iframe_canvas.setAttribute("height", 30);
var iframe_ctx = iframe_canvas.getContext("2d");
// copy image from window canvas to iframe ctx
iframe_ctx.drawImage(canvas, 0, 0);
return iframe_canvas.toDataURL();
}