Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.javascript > #25549

Re: Canvas Fingerprinting

Show all headers | View raw

In comp.lang.javascript, Andrew Poulos  <ap_prog@hotmail.com> wrote:
> If you "know" the canvas element already and the canvas is "filled" 
> using js why can't you just send the js to the server?

Let's use an analogy. The "canvas" is a sheet of paper (hardware), drawn
on by a pen (hardware) in the user's hand (software). The "javascript"
is the directions for what to do.

If you just send the directions back, they look a whole lot like what
they did when they were first sent out.

If the user follows the directions to write some text on the sheet of
paper and then sends a photo of the results back, that's a lot closer
to the canvas fingerprinting scenario. The results in our example show
pen choice, paper choice, handwriting choice, etc. 

In the real canvas fingerprint, the image itself is not sent to the
site, only some information (a "fingerprint") of the image. But it still
relies detecting on software and hardware variations in following
directions exactly. In this case the directions are specifically
selected to be likely to produce variations, things like blending
colored text on top of other colored text.

Elijah
------
http://www.browserleaks.com/ has a sample of the canvas test

Back to comp.lang.javascript | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Canvas Fingerprinting Andrew Poulos <ap_prog@hotmail.com> - 2014-07-23 13:33 +1000
  Re: Canvas Fingerprinting Andrew Poulos <ap_prog@hotmail.com> - 2014-07-23 15:23 +1000
    Re: Canvas Fingerprinting Andrew Poulos <ap_prog@hotmail.com> - 2014-07-23 17:48 +1000
      Re: Canvas Fingerprinting Eli the Bearded <*@eli.users.panix.com> - 2014-07-23 18:43 +0000
        Re: Canvas Fingerprinting Andrew Poulos <ap_prog@hotmail.com> - 2014-07-24 08:39 +1000

csiph-web