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Re: [tor-talk] [Tails-dev] secure and simple network time (hack)

> Hi,
> Jacob Appelbaum wrote (19 Jul 2012 23:48:48 GMT) :
>> intrigeri:
>>> So, Jake tells me that ChromeOS will use tlsdate by default, and that
>>> this should solve the fingerprinting issue. Therefore, I assume this
>>> implicitly answer the (half-rhetorical, I admit) question I asked in
>>> March, and I assume there is indeed some fingerprinting issue. So, in
>>> the following I'll assume it's relatively easy, for a close network
>>> adversary (say, my ISP) to detect that I'm using tlsdate.
>> It isn't shipping yet, so we'll see what happens.
> I'm told ChromeOS ships it nowadays, so I'm excited at the idea to
> learn more about it, so that we can move forward a bit about the
> fingerprinting issue.

It does indeed - their network time document is here:


> I was not able to find any authoritative information about how they
> run it. Their time sources [1] design doc is quite clearly outdated.
> Where can I find up-to-date information on this topic? I assume one of
> the dozens of Chromius Git repositories [2], but which one?
> [1] http://www.chromium.org/developers/design-documents/time-sources
> [2] http://git.chromium.org/gitweb/

Basically - tlsdate in Tails would be a minor set of users compared to
the much larger user base of ChromeOS.

I've also just updated the INSTALL file to document the different places
that git-master of tlsdate works:

  Debian Gnu/Linux 6.0.7
  Ubuntu 11.04, 12.04, 12.10
  CentOS 6.2, 6.3
  Fedora 17, 18
  RedHat Enterprise Server 6.4
  OpenSUSE 11.2, 12.3
  Mac OS X 10.8.2, 10.8.3
  ChromeOS 26.0.x.x, 27.0.x.x (tlsdate is part of the ChromeOS TCB!)

I'd like to settle on a list of hosts that it uses by default which may
include a Google host or not. I haven't yet decided.

All the best,
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