#3323: Revisit WebGL
-------------------------------------------------+--------------------------
Reporter: mikeperry | Owner: mikeperry
Type: defect | Status: new
Priority: major | Milestone:
TorBrowserBundle 2.3.x-stable
Component: TorBrowserButton | Version:
Keywords: tbb-fingerprinting, MikePerry201206 | Parent:
Points: | Actualpoints:
-------------------------------------------------+--------------------------
Comment(by mikeperry):
Replying to [comment:1 mikeperry]:
> The API calls that concern me for fingerprinting issues are:
> getParameter() specifically RENDERER, VENDOR, VERSION, and VIEWPORT.
This is implemented in WebGLContext::GetParameter(). It appears that
RENDERER, VENDOR, and VERSION are all actually Mozilla strings. I should
double-check these things aren't available elsewhere, too.
"Minimal mode" appears to apply to this GetParameter() function
(specifically the parameters surrounding texture, buffer, vector and
vertex attribute sizes), and is exported as
WebGLContext::MinCapabilityMode(). It looks like it in fact can serve to
defend against normalizing some fingerprintable attributes. It is also
used in WebGLContext::InitAndValidateGL() for the setting same values as
member variables there.
The VIEWPORT is not governed by minimal mode.
> getSupportedExtensions() and getExtension()
These two are in fact fully disabled by webgl.disable_extensions, which
has no other effect atm.
> getContextAttributes() mostly for the display depth..
Not governed by minimal mode.
--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3323#comment:9>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online
_______________________________________________
tor-bugs mailing list
[email protected]
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-bugs
