Discussion:
[tor-talk] Making TBB undetectable!
behnaz Shirazi
2015-09-26 13:51:02 UTC
Permalink
In many different cases TBB users have to be undetectable (bypassing
flags, escaping from deep investigations, confusing malicious iframes
etc etc) when traffic flows through custom Tor exite nodes or even
when traffic flows directly just for the privacy TBB offers at client
side compared to plain Firefox.


TBB have a distinguishable User-Agent and screen size that can be
easily changed to something more common but it also have other
fingerprints that are hard to change, such as timezone=0 or
navigator.plugins=none or some dialogs [1] [2]. And TBB have even more
fingerprints that we are not aware of yet


Can someone please teach Tor users how to modify the source code and
compile a custom build or create browser Add-ons that subvert these
detection methods? There must be an option for those who urgently
(...) need undetectability and it doesn't require much effort to make
that happen.


[1]: https://www.browserleaks.com/canvas
[2]: https://www.browserleaks.com/firefox
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
aka
2015-09-26 15:45:09 UTC
Permalink
Can't TBB devs just patch in a hardcoded 1366x768 window and screen size
in the javascript handler?

Also, if you want true undetectability you need to install a Tor
instance and your OS for TBB in seperate VMs and setup the Tor VM to be
a transparent router for your OS, so even if java/flash/exploit is
executed, it doesn't leak your real IP, since even your OS in the VM is
forced through Tor.
The FBI used an old firefox exploit to execute native code and did plain
IP requests to uncover users. In that configuration they would need an
additional VM escape exploit, which raises the cost exponentially.
Post by behnaz Shirazi
In many different cases TBB users have to be undetectable (bypassing
flags, escaping from deep investigations, confusing malicious iframes
etc etc) when traffic flows through custom Tor exite nodes or even
when traffic flows directly just for the privacy TBB offers at client
side compared to plain Firefox.
TBB have a distinguishable User-Agent and screen size that can be
easily changed to something more common but it also have other
fingerprints that are hard to change, such as timezone=0 or
navigator.plugins=none or some dialogs [1] [2]. And TBB have even more
fingerprints that we are not aware of yet
Can someone please teach Tor users how to modify the source code and
compile a custom build or create browser Add-ons that subvert these
detection methods? There must be an option for those who urgently
(...) need undetectability and it doesn't require much effort to make
that happen.
[1]: https://www.browserleaks.com/canvas
[2]: https://www.browserleaks.com/firefox
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Dave Warren
2015-09-27 07:40:32 UTC
Permalink
No, you can't just patch in a hardcoded window and screen size unless it
reflects the actual viewport size.

JavaScript is often used to position elements using relatively absolute
positioning based on the viewport that it understands is correct, this
will fail if the viewport vs reported size isn't accurate. More
importantly, it won't even work, JavaScript can detect where wrapping
happens, and some creative 1 pixel tall transparent images could detect
the actual horizontal width by using varying widths.
Post by aka
Can't TBB devs just patch in a hardcoded 1366x768 window and screen size
in the javascript handler?
Also, if you want true undetectability you need to install a Tor
instance and your OS for TBB in seperate VMs and setup the Tor VM to be
a transparent router for your OS, so even if java/flash/exploit is
executed, it doesn't leak your real IP, since even your OS in the VM is
forced through Tor.
The FBI used an old firefox exploit to execute native code and did plain
IP requests to uncover users. In that configuration they would need an
additional VM escape exploit, which raises the cost exponentially.
Post by behnaz Shirazi
In many different cases TBB users have to be undetectable (bypassing
flags, escaping from deep investigations, confusing malicious iframes
etc etc) when traffic flows through custom Tor exite nodes or even
when traffic flows directly just for the privacy TBB offers at client
side compared to plain Firefox.
TBB have a distinguishable User-Agent and screen size that can be
easily changed to something more common but it also have other
fingerprints that are hard to change, such as timezone=0 or
navigator.plugins=none or some dialogs [1] [2]. And TBB have even more
fingerprints that we are not aware of yet
Can someone please teach Tor users how to modify the source code and
compile a custom build or create browser Add-ons that subvert these
detection methods? There must be an option for those who urgently
(...) need undetectability and it doesn't require much effort to make
that happen.
[1]: https://www.browserleaks.com/canvas
[2]: https://www.browserleaks.com/firefox
--
Dave Warren
http://www.hireahit.com/
http://ca.linkedin.com/in/davejwarren
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
behnaz Shirazi
2015-09-26 18:38:47 UTC
Permalink
Post by aka
Can't TBB devs just patch in a hardcoded 1366x768 window and screen size
in the javascript handler?
Anonymity for Tor devs is a priority and they don't like give
different browser fingerprints to their users because that plan makes
Tor users in each web service more unique as very few people actually
use Tor at each website, however uniqueness of user won't deanonymize
it right away, it depends on using same unique fingerprint on another
webservice that will confess user's identity and let attacker link the
pseudonymous identity to a real identity that used same browser
fingerprint.

An optional tool that allows users temporarily make their TBB
undetectable whenever they need doesn't hurt anonymity of Tor network
at all.

I believe writing a browser Add-on that contains several common
profiles (desktop tablet and mobile configurations) or let users
manually define what their browser should return in response to data
requests, would be ridiculously easy.

And there is no need to wait for Tor developers to build such a
tool/guide, any third party can help.
Post by aka
Also, if you want true undetectability you need to install a Tor
instance and your OS for TBB in seperate VMs and setup the Tor VM to be
a transparent router for your OS, so even if java/flash/exploit is
executed, it doesn't leak your real IP, since even your OS in the VM is
forced through Tor.
No I don't talk about anonymity, I'm asking to fix detectability.
destination website shouldn't be able to detect user is using TBB,
some people think only problematic guys use TBB and Detecting it cause
a lots of problems in different scenarios (in my own case, for some
reasons i'm worry about QUANTUM_INSERT like programs that can
automatically attack me if they think i'm a suspicious user)

And there is no need to play flash/java in the game, lots of ordinary
people are uninstalling those malware-vectore plugins. Java is dead
and flash has to die, too.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Jeremy Rand
2015-09-26 19:44:25 UTC
Permalink
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Post by behnaz Shirazi
Post by aka
Also, if you want true undetectability you need to install a Tor
instance and your OS for TBB in seperate VMs and setup the Tor VM
to be a transparent router for your OS, so even if
java/flash/exploit is executed, it doesn't leak your real IP,
since even your OS in the VM is forced through Tor.
No I don't talk about anonymity, I'm asking to fix detectability.
destination website shouldn't be able to detect user is using TBB,
some people think only problematic guys use TBB and Detecting it
cause a lots of problems in different scenarios (in my own case,
for some reasons i'm worry about QUANTUM_INSERT like programs that
can automatically attack me if they think i'm a suspicious user)
Maybe I'm not understanding you, but given that all TBB users are
already distinguishable from other users since their IP address is a
Tor exit, I'm not seeing how TorBrowser having a different fingerprint
from other browsers is a problem. The important thing is that
TorBrowser users have the same fingerprint as each other, which the
TorBrowser devs seem to be doing a good job on.

Cheers,
- -Jeremy Rand
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=HCiV
-----END PGP SIGNATURE-----
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
AMuse
2015-09-28 16:23:51 UTC
Permalink
Having a unique, or unique enough browser fingerprint would allow
website owners and content network providers to track a TOR user across
nodes and/or sessions. With a large enough CDN (facebook, etc) you could
reasonably de-anonymize a user.
Post by Jeremy Rand
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Also, if you want true undetectability you need to install a Tor instance and your OS for TBB in seperate VMs and setup the Tor VM to be a transparent router for your OS, so even if java/flash/exploit is executed, it doesn't leak your real IP, since even your OS in the VM is forced through Tor. No I don't talk about anonymity, I'm asking to fix detectability. destination website shouldn't be able to detect user is using TBB, some people think only problematic guys use TBB and Detecting it cause a lots of problems in different scenarios (in my own case, for some reasons i'm worry about QUANTUM_INSERT like programs that can automatically attack me if they think i'm a suspicious user)
Maybe I'm not understanding you, but given that all TBB users are
already distinguishable from other users since their IP address is a
Tor exit, I'm not seeing how TorBrowser having a different fingerprint
from other browsers is a problem. The important thing is that
TorBrowser users have the same fingerprint as each other, which the
TorBrowser devs seem to be doing a good job on.

Cheers,
- -Jeremy Rand
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=HCiV
-----END PGP SIGNATURE-----
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
behnaz Shirazi
2015-10-01 11:09:15 UTC
Permalink
Post by Jeremy Rand
Maybe I'm not understanding you, but given that all TBB users are
already distinguishable from other users since their IP address is a
Tor exit, I'm not seeing how TorBrowser having a different fingerprint
from other browsers is a problem. The important thing is that
TorBrowser users have the same fingerprint as each other, which the
TorBrowser devs seem to be doing a good job on.
False! A unique Tor exit IP that visits site1.com then site2.com won't
compromise same person visited those sites or tow different person who
used same Tor exit IP at the same time did that, thus anonymity
remains true.
Post by Jeremy Rand
No, you can't just patch in a hardcoded window and screen size unless it reflects the actual >viewport size.
JavaScript is often used to position elements using relatively absolute positioning based on >the viewport that it understands is correct, this will fail if the viewport vs reported size isn't >accurate. More importantly, it won't even work, JavaScript can detect where wrapping >happens, and some creative 1 pixel tall transparent images could detect the actual horizontal >width by using varying widths.
Browser Add-ons can change actual view size to anything we plan.
Post by Jeremy Rand
Having a unique, or unique enough browser fingerprint would allow
website owners and content network providers to track a TOR user across
nodes and/or sessions. With a large enough CDN (facebook, etc) you could
reasonably de-anonymize a user.
That is correct. But a Tor user who temporarily use a natural
fingerprint to become undetectable for a while won't deanonymize
itself nor the rest of other Tor users who use a detectable version of
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization, and for sure Tor users who need undetectability won't
use the undetectablizer Add-on all the time hence detectable TBB users
won't become unique.

Undetectability is a crucial requirement for privacy protection tools
and unfortunately seems that Tor developers don't wanna put their time
on this issue. I hope other folks take this problem serious and do
something quickly.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Ben Tasker
2015-10-01 11:31:16 UTC
Permalink
Post by behnaz Shirazi
False! A unique Tor exit IP that visits site1.com then site2.com won't
compromise same person visited those sites or tow different person who
used same Tor exit IP at the same time did that, thus anonymity
remains true.
But if one has one fingerprint (the default TBB) and the other an
'undetectable' one, then you can easily differentiate that they are two
different users. They both came from Tor exits, so you "know" they're TOR
users, but one user changing TBB's signature means they no longer appear as
close to identical as possible.
Post by behnaz Shirazi
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization,
Used once, sure. But over time, it's likely going to get used more than
once, unless you're planning on inserting some sort of randomisation to try
and prevent that (by making some aspect different each session), but that
randomisation then becomes a potential means to identify users who are
using "UnidentifiableMode"
Post by behnaz Shirazi
Undetectability is a crucial requirement for privacy protection tools
and unfortunately seems that Tor developers don't wanna put their time
on this issue. I hope other folks take this problem serious and do
something quickly.
I don't _know_ but I suspect it's actually the opposite - thought has
previously been put into the feasibility and risk and it's been decided
that the current approach should be safer. Making something "Undetectable"
is very, very hard as your margin for error is 0 (because 0.01 gives
something that someone could use to make it identifiable). Making something
common so you can blend into the crowd makes it easier to avoid
(potentially) costly mistakes.

Remember that those who are _really_ interested in de-anonymising via
fingerprinting are _very_ good at finding means to differentiate between
requests, one tiny slip-up is all it would take to make your
"Unidentifiable" browser extremely identifiable. You'd then (potentially)
be the only client with fingerprint a, coming from a Tor exit.

Even if you didn't slip up, let's say you make your requests look almost
exactly like vanilla firefox. If you're the only user using that mode at a
given time, every request coming from an exit with your fingerprint is an
opportunity to correlate that traffic back to you. There's no immediate
proof that all that traffic is you, but volumes would be low enough that
you could then start examining requests with an aim to trying to prove it's
all one user.

Blending into the crowd is not without it's value.
Post by behnaz Shirazi
Post by Jeremy Rand
Maybe I'm not understanding you, but given that all TBB users are
already distinguishable from other users since their IP address is a
Tor exit, I'm not seeing how TorBrowser having a different fingerprint
from other browsers is a problem. The important thing is that
TorBrowser users have the same fingerprint as each other, which the
TorBrowser devs seem to be doing a good job on.
False! A unique Tor exit IP that visits site1.com then site2.com won't
compromise same person visited those sites or tow different person who
used same Tor exit IP at the same time did that, thus anonymity
remains true.
Post by Jeremy Rand
No, you can't just patch in a hardcoded window and screen size unless it
reflects the actual >viewport size.
Post by Jeremy Rand
JavaScript is often used to position elements using relatively absolute
positioning based on >the viewport that it understands is correct, this
will fail if the viewport vs reported size isn't >accurate. More
importantly, it won't even work, JavaScript can detect where wrapping
Post by Jeremy Rand
happens, and some creative 1 pixel tall transparent images could detect
the actual horizontal >width by using varying widths.
Browser Add-ons can change actual view size to anything we plan.
Post by Jeremy Rand
Having a unique, or unique enough browser fingerprint would allow
website owners and content network providers to track a TOR user across
nodes and/or sessions. With a large enough CDN (facebook, etc) you could
reasonably de-anonymize a user.
That is correct. But a Tor user who temporarily use a natural
fingerprint to become undetectable for a while won't deanonymize
itself nor the rest of other Tor users who use a detectable version of
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization, and for sure Tor users who need undetectability won't
use the undetectablizer Add-on all the time hence detectable TBB users
won't become unique.
Undetectability is a crucial requirement for privacy protection tools
and unfortunately seems that Tor developers don't wanna put their time
on this issue. I hope other folks take this problem serious and do
something quickly.
--
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
--
Ben Tasker
https://www.bentasker.co.uk
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Spencer
2015-10-01 17:07:39 UTC
Permalink
Hi,
Post by Ben Tasker
Post by behnaz Shirazi
a Tor user who temporarily use a natural
fingerprint to become undetectable for a while won't deanonymize
itself nor the rest of other Tor users who use a detectable version of
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization,
Is a 'Natural Fingerprint' like a clearnet fingerprint, in that it
identifies you as a regular, non-tor, internet user, making you part of
the larger herd?
Post by Ben Tasker
Post by behnaz Shirazi
and for sure Tor users who need undetectability won't
use the undetectablizer Add-on all the time hence detectable TBB users
won't become unique.
I see this as a blocker, as this add-on is most likely detectable, yeah?
If not, how, in the same, less, or maybe a bit more, amount of
resources do you feel this could be accomplished? Manually, this
becomes quite the task as time progresses. Is this something that would
be added to a mail [something], like OpenPGP or TorBirdy are, because I
feel like this would be detectable somehow, too.
Post by Ben Tasker
Used once, sure. But over time, it's likely going to get used more than
once,
This seems to be part of the design, as one-of-a-kind fingerprints,
through Tor exits or not, are detectable, though probably not
identifiable.
Post by Ben Tasker
unless you're planning on inserting some sort of randomisation to try
and prevent that (by making some aspect different each session),
Randomization, or some one click equivalent, is the only real option
here when usability is considered; the manual effort each session is
undesirable at the very least :)
Post by Ben Tasker
using "UnidentifiableMode"
'UnidentifiableMode' sounds like a good working name for such a feature.
Post by Ben Tasker
Making something "Undetectable"
is very, very hard as your margin for error is 0 (because 0.01 gives
something that someone could use to make it identifiable). Making something
common so you can blend into the crowd makes it easier to avoid
(potentially) costly mistakes.
Making people blend into the crowd of regular internet users is best but
only if we resolve the traffic source; i.e., Tor exits.
Post by Ben Tasker
Blending into the crowd is not without it's value.
But surely some of these fingerprints will be shared by real users. So,
it seems like a reasonable request, should we resolve the usability and
*traffic issues.

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Ben Tasker
2015-10-01 18:18:48 UTC
Permalink
Randomization, or some one click equivalent, is the only real option here
when usability is considered; the manual effort each session is undesirable
at the very least :)

The problem you have there, is what to randomize, and how to do it in such
a way that it does not itself become identifiable.

To use an example, think about when you run cover traffic (whether over Tor
or a VPN), the initial temptation is to have random levels of data
travelling over the link. The problem there being it's not a 'natural'
looking flow of data when you analyse it. So when you use the link, your
natural usage is identifiable in the analysis.

So you go for something more 'natural', but natural's hard to fake, so your
cover traffic has an identifiable set of patterns, meaning on analysis you
can discount it and still tell when the tunnel is being used for real
traffic.


When we're talking about making the browser unidentifiable as TBB, the very
act of having something in the fingerprint that changes to prevent
correlation between sessions provides an avenue by which it can be
identified as TBB:

Let's say you override reported screen width so it lies, and then use TBB
to sign in to (sake of example) Facebook. Every time you start a new
session and sign in to Facebook, your screen size is going to be different.
That's *very* unusual. User's screen sizes will change from time to time
(because they're in a window rather than full-screen, or on a laptop
instead of a PC) but to be different every time?

What about if you're signed in to FB in one tab, and browsing news in
another. The news page has a Like button on it, and Facebook get a
completely different screen size reported. You might just have the news on
fullscreen, and FB windowed, but again, for it to happen every time is an
unusual pattern.

A bit of research would soon tell them you're using TBB even if they hadn't
thought to see if the traffic was coming from an exit node.
Making people blend into the crowd of regular internet users is best but
only if we resolve the traffic source; i.e., Tor exits.

That's quite an issue to solve though. Even if we assume that the IP's of
tor nodes weren't being published anymore, analysis of traffic patterns on
a busy site would likely soon let you work out the IP's of some exits.

Granted, you wouldn't immediately know whether those sources were Tor exits
or simply proxies being used by multiple users, but finding out wouldn't be
impossible. A determined adversary wanting to map out Tor exits could
simply initiate a lot of connections via Tor and keep a record of where the
other end (under their control) sees connections come from.

Not as accurate as downloading the relay list, but depending on your aims
you wouldn't need 100% coverage, so in the absence of the list it'd
probably do. It raises the cost of identifying Tor exits, but only so long
as the resulting list isn't then published (and kept up to date).

As others have said though, the aim isn't to hide that you're using Tor
from your destination, and successfully doing so would (IMO) be a pretty
non-trivial task
Hi,
Post by Ben Tasker
Post by behnaz Shirazi
a Tor user who temporarily use a natural
fingerprint to become undetectable for a while won't deanonymize
itself nor the rest of other Tor users who use a detectable version of
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization,
Is a 'Natural Fingerprint' like a clearnet fingerprint, in that it
identifies you as a regular, non-tor, internet user, making you part of the
larger herd?
Post by Ben Tasker
Post by behnaz Shirazi
and for sure Tor users who need undetectability won't
use the undetectablizer Add-on all the time hence detectable TBB users
won't become unique.
I see this as a blocker, as this add-on is most likely detectable, yeah?
If not, how, in the same, less, or maybe a bit more, amount of resources do
you feel this could be accomplished? Manually, this becomes quite the task
as time progresses. Is this something that would be added to a mail
[something], like OpenPGP or TorBirdy are, because I feel like this would
be detectable somehow, too.
Post by Ben Tasker
Used once, sure. But over time, it's likely going to get used more than
once,
This seems to be part of the design, as one-of-a-kind fingerprints,
through Tor exits or not, are detectable, though probably not identifiable.
Post by Ben Tasker
unless you're planning on inserting some sort of randomisation to try
and prevent that (by making some aspect different each session),
Randomization, or some one click equivalent, is the only real option here
when usability is considered; the manual effort each session is undesirable
at the very least :)
Post by Ben Tasker
using "UnidentifiableMode"
'UnidentifiableMode' sounds like a good working name for such a feature.
Post by Ben Tasker
Making something "Undetectable"
is very, very hard as your margin for error is 0 (because 0.01 gives
something that someone could use to make it identifiable). Making something
common so you can blend into the crowd makes it easier to avoid
(potentially) costly mistakes.
Making people blend into the crowd of regular internet users is best but
only if we resolve the traffic source; i.e., Tor exits.
Post by Ben Tasker
Blending into the crowd is not without it's value.
But surely some of these fingerprints will be shared by real users. So,
it seems like a reasonable request, should we resolve the usability and
*traffic issues.
Wordlife,
Spencer
--
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
--
Ben Tasker
https://www.bentasker.co.uk
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
behnaz Shirazi
2015-10-02 16:58:12 UTC
Permalink
Post by Ben Tasker
Post by behnaz Shirazi
False! A unique Tor exit IP that visits site1.com then site2.com won't
compromise same person visited those sites or tow different person who
used same Tor exit IP at the same time did that, thus anonymity
remains true.
But if one has one fingerprint (the default TBB) and the other an
'undetectable' one, then you can easily differentiate that they are two
different users. They both came from Tor exits, so you "know" they're TOR
users, but one user changing TBB's signature means they no longer appear as
close to identical as possible.
As I said it won't happen. It doesn't make sense to use
undetectableizer when using a public Tor exit node because that will
compromise you are using Tor thereby minority of undetectable users
won't hurt anonymity of major detectable users nor themselves.
undetectablizer Add-on is useful for private exit nodes. just think of
how Tor bridges are shared with users privately to prevent China
harvest and block all of them, a similar list can be provided by Tor
community or other groups to share private exit nodes after paying
some Bitcoins and anyone can mine Bitcoins anonymously by doing
computer works after a few days.

Undetectability is necessary but occasional. Most of the time you
don't need to be undetectable when searching websites or visiting
social networks but if attacker detect that someone is trying to hide
it's identity when entering a powerful vile's email account or when
trying to contact a high risk journalist, that might cost lives.
Post by Ben Tasker
Post by behnaz Shirazi
TBB because when a natural fingerprint is used once then there will be
no enough information available for data miners to link pseudonyms for
deanonymization,
Used once, sure. But over time, it's likely going to get used more than
once, unless you're planning on inserting some sort of randomisation to try
and prevent that (by making some aspect different each session), but that
randomisation then becomes a potential means to identify users who are
using "UnidentifiableMode"
Yes. Using a randomized profiles each time user clicks on
UnidentifiableMode can solve reusing same unique fingerprint problem
however I prefer use common profiles that we have in mobile devices
because a lots of people are using them and they all have same
fingerprint. it would be a large haystack for hiding, if I several
times check same account from there I still look natural.
Post by Ben Tasker
Post by behnaz Shirazi
Undetectability is a crucial requirement for privacy protection tools
and unfortunately seems that Tor developers don't wanna put their time
on this issue. I hope other folks take this problem serious and do
something quickly.
I don't _know_ but I suspect it's actually the opposite - thought has
previously been put into the feasibility and risk and it's been decided
that the current approach should be safer. Making something "Undetectable"
is very, very hard as your margin for error is 0 (because 0.01 gives
something that someone could use to make it identifiable). Making something
common so you can blend into the crowd makes it easier to avoid
(potentially) costly mistakes.
Remember that those who are _really_ interested in de-anonymising via
fingerprinting are _very_ good at finding means to differentiate between
requests, one tiny slip-up is all it would take to make your
"Unidentifiable" browser extremely identifiable. You'd then (potentially)
be the only client with fingerprint a, coming from a Tor exit.
There are limited numbers of data requests possible (check out
browserleaks.com or browserspy.dk). We need list all of them and
compare with other browsers to spoof what is different.
Post by Ben Tasker
Even if you didn't slip up, let's say you make your requests look almost
exactly like vanilla firefox. If you're the only user using that mode at a
given time, every request coming from an exit with your fingerprint is an
opportunity to correlate that traffic back to you. There's no immediate
proof that all that traffic is you, but volumes would be low enough that
you could then start examining requests with an aim to trying to prove it's
all one user.
Blending into the crowd is not without it's value.
You say that in UnidentifiableMode before closing the browser and
getting a new identity, opening different sites in different tabs can
be correlated to each other which is true if user choose a randomized
fingerprint however if a common fingerprint like mobile devices is
chosen then that correlation between different tabs becomes
impractical.

UnidentifiableMode is used in rare scenarios, in a dialog we can
inform users what happens when they activate it. At the moment If you
maximize TBB a message pop up and inform you that this action makes
you vulnerable to tracking.
Post by Ben Tasker
Is a 'Natural Fingerprint' like a clearnet fingerprint, in that it identifies you as a regular, >non-tor, internet user, making you part of the larger herd?
I don't understand what do you mean by “clearnet fingerprint” ?
Fingerprint is generated locally inside the browser, it is about TBB
not the onion routers. Connecting to a website directly or via a
public Tor exit node as proxy gives one bit of information (true or
false flag) to destination website but we don't include this bit in
the fingerprinting attack.
Post by Ben Tasker
I see this as a blocker, as this add-on is most likely detectable, yeah?
Nah
Post by Ben Tasker
I see this as a blocker, as this add-on is most likely detectable, yeah?
If not, how, in the same, less, or maybe a bit more, amount of
resources do you feel this could be accomplished? Manually, this
becomes quite the task as time progresses. Is this something that would
be added to a mail [something], like OpenPGP or TorBirdy are, because I
feel like this would be detectable somehow, too.
As far as I know you can't fetch installed Add-ons by javascript, it
only works for plugins so it is not detectable either. Detecting
Add-ons is done by side channel attacks, for instance Adblock prevent
certain scripts or Noscript prevent certain objects, attacker can
simply call such elements and find out those Add-ons are already
installed or not.

We just change details a browser return to calls in a way that caller
can't recognize it is telling the truth or not. there is no need to
block things however the "resource://" should go away, it tells
everything even the exact Tor version you are using now. of course it
won't cause a detection if user choose a mobile device profile as
safari don't have such a thing.
Post by Ben Tasker
Post by behnaz Shirazi
Randomization, or some one click equivalent, is the only real option here
when usability is considered; the manual effort each session is undesirable
at the very least :)
The problem you have there, is what to randomize, and how to do it in such
a way that it does not itself become identifiable.
To use an example, think about when you run cover traffic (whether over Tor
or a VPN), the initial temptation is to have random levels of data
travelling over the link. The problem there being it's not a 'natural'
looking flow of data when you analyse it. So when you use the link, your
natural usage is identifiable in the analysis.
So you go for something more 'natural', but natural's hard to fake, so your
cover traffic has an identifiable set of patterns, meaning on analysis you
can discount it and still tell when the tunnel is being used for real
traffic.
When we're talking about making the browser unidentifiable as TBB, the very
act of having something in the fingerprint that changes to prevent
correlation between sessions provides an avenue by which it can be
Let's say you override reported screen width so it lies, and then use TBB
to sign in to (sake of example) Facebook. Every time you start a new
session and sign in to Facebook, your screen size is going to be different.
That's *very* unusual. User's screen sizes will change from time to time
(because they're in a window rather than full-screen, or on a laptop
instead of a PC) but to be different every time?
What about if you're signed in to FB in one tab, and browsing news in
another. The news page has a Like button on it, and Facebook get a
completely different screen size reported. You might just have the news on
fullscreen, and FB windowed, but again, for it to happen every time is an
unusual pattern.
A bit of research would soon tell them you're using TBB even if they hadn't
thought to see if the traffic was coming from an exit node.
Using a common fingerprint (e.g mobiles) all the time can solve this issue
Post by Ben Tasker
only if we resolve the traffic source; i.e., Tor exits.
That's quite an issue to solve though. Even if we assume that the IP's of
tor nodes weren't being published anymore, analysis of traffic patterns on
a busy site would likely soon let you work out the IP's of some exits.
Granted, you wouldn't immediately know whether those sources were Tor exits
or simply proxies being used by multiple users, but finding out wouldn't be
impossible. A determined adversary wanting to map out Tor exits could
simply initiate a lot of connections via Tor and keep a record of where the
other end (under their control) sees connections come from.
Not as accurate as downloading the relay list, but depending on your aims
you wouldn't need 100% coverage, so in the absence of the list it'd
probably do. It raises the cost of identifying Tor exits, but only so long
as the resulting list isn't then published (and kept up to date).
In a public wifi hotspot there is only one IP address and several
clients simultaneously visit different websites. It would be very
difficult for an attacker to find out a private Tor exit node is
actually a Tor exit node and what we want is to prevent websites be
able to instantly detect Tor like today. Don't forget that it is not
impossible to locate a user if a global adversary observe a big
portion of globe and deanonymize Tor itself but we still trust Tor for
anonymity thus we can trust undetectablizer Add-on in most of cases to
remain unidentifiable either.
Post by Ben Tasker
As others have said though, the aim isn't to hide that you're using Tor
from your destination, and successfully doing so would (IMO) be a pretty
non-trivial task
What? Undetectabilizer Add-on's aim is exactly hiding that we're using
Tor from the destination site. Pluggable Transports aim to hide that
we're using Tor from network observers located between user and
entry-guards.

Making undetectablizer Add-on is a trivial task. It took several years
for Tor devs to show up a warning message when user try maximize it's
browser. It was a trivial task too but they are busy with other things
and don't have enough resource to do more good stuff. I hope they run
a kickstarter campaign very soon or some other folk help out make this
Add-on happen.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torprojec
s***@quantentunnel.de
2015-10-03 04:44:34 UTC
Permalink
Post by behnaz Shirazi
As I said it won't happen. It doesn't make sense to use
undetectableizer when using a public Tor exit node because that will
compromise you are using Tor thereby minority of undetectable users
won't hurt anonymity of major detectable users nor themselves.
Since TBB uses the consensus this discussion is quite nonsensical,
you can't hide the fact that you use tor from the site you visit,
not with an addon or a bridge, while using tor.

Since the consensus data is available, I do
grep "^r " /var/lib/tor/cached-consensus | cut -d \ -f 7
and have a handy list. For historic data one uses exonerator.
Since this list contains all kind of nodes (6651 atm), we make
sure not to miss anyone involved using tor or someone getting
promoted. :)

Want to know how may Exits are available? 1081 atm, to verify try
grep "^s Exit" /var/lib/tor/cached-consensus | wc -l

So, detecting Tor usage at an endpoint is a very trivial exercise.

By using a private exit, you are actually increasing chances to become
a victim of a correlation attack, since an adversary needs to observe
the private exit only, may inject patterns and try to observe
this patterns somewere. For enduring connections like bitcoin, it may be
enough to interrupt/shape/reset connections and look for whom bitcoin
isn't working anymore - there aren't much full nodes anymore.

It may work for a mining pool, but not for an individual miner. I am
not going into the subtle details of different, easy to detect
fingerprints within the protocol.

Lets not digress, back to TBB: if you allow cookies, caching or javascript
this gets even worse. If you authenticate (like using a password or a public
key), you are unique. If you use data of an oob protocol within tor
(like a bitcoin) chances are pretty high you become unique and traceable
(reddit provides a neat list of mistakes made with tor and bitcoin).

Btw., TBB isn't designed to hide usage patterns. If you want that,
invite some friends over to surf or run a node, a relay, bridge or exit.

The benefits of tor are few but they are still awesome, you can hide the
fact that you use something from a local authority, like your ISP or an
upstream adversary and you can hide your location/origin.

If you involve a bridge, you may hide the fact that you use tor from
a local authority, but you can't hide this fact from an endpoint.

Try hiding the fact, that you use tor from a hidden service. :)

Thats all, TBB is limiting that to https, if you use http you
become vulnerable against malicious exit nodes.

So, please forget about hiding the fact that you use tor, by using
tor, from an endpoint - it won't work.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
behnaz Shirazi
2015-10-03 09:16:50 UTC
Permalink
Post by s***@quantentunnel.de
Since TBB uses the consensus this discussion is quite nonsensical,
you can't hide the fact that you use tor from the site you visit,
not with an addon or a bridge, while using tor.
Since the consensus data is available, I do
grep "^r " /var/lib/tor/cached-consensus | cut -d \ -f 7
and have a handy list. For historic data one uses exonerator.
Since this list contains all kind of nodes (6651 atm), we make
sure not to miss anyone involved using tor or someone getting
promoted. :)
Want to know how may Exits are available? 1081 atm, to verify try
grep "^s Exit" /var/lib/tor/cached-consensus | wc -l
So, detecting Tor usage at an endpoint is a very trivial exercise.
A private Tor exit node is not listed in consensus. And there is no
need to use a private exit node for undetectability, we can simply use
a public exit node that is connected to a socks proxy server thereby
destination site can't see exit node's IP address and match it with
consensus.
Post by s***@quantentunnel.de
By using a private exit, you are actually increasing chances to become
a victim of a correlation attack, since an adversary needs to observe
the private exit only, may inject patterns and try to observe
this patterns somewere. For enduring connections like bitcoin, it may be
enough to interrupt/shape/reset connections and look for whom bitcoin
isn't working anymore - there aren't much full nodes anymore.
It may work for a mining pool, but not for an individual miner. I am
not going into the subtle details of different, easy to detect
fingerprints within the protocol.
If we use a socks proxy server to talk with destination instead of a
private Tor exit node then such an attack becomes as dangerous as when
you are using a detectable TBB over a public Tor exit node because the
number of socks proxies available out there won't be less than public
Tor exit nodes today.
Post by s***@quantentunnel.de
Lets not digress, back to TBB: if you allow cookies, caching or javascript
this gets even worse. If you authenticate (like using a password or a public
key), you are unique. If you use data of an oob protocol within tor
(like a bitcoin) chances are pretty high you become unique and traceable
(reddit provides a neat list of mistakes made with tor and bitcoin).
in UnidentifiableMode if you use a randomized fingerprint then you are
unique until you close your browser and during that session different
sites you open in different tabs can identify same person is visiting
these sites but if you use a common fingerprint like a mobile device
that is same for everyone then you are not unique among undetectable
users.
Post by s***@quantentunnel.de
Btw., TBB isn't designed to hide usage patterns. If you want that,
invite some friends over to surf or run a node, a relay, bridge or exit.
It's really impractical to ask a friend install a RAT and let me
backconnect to surf the Internet using his web browser. We can patch
TBB or create an Add-on that let anyone in special cases easily visit
destination sites anonymously and invisibly.
Post by s***@quantentunnel.de
The benefits of tor are few but they are still awesome, you can hide the
fact that you use something from a local authority, like your ISP or an
upstream adversary and you can hide your location/origin.
Why not expand those few benefits into more awesomeness?
Post by s***@quantentunnel.de
If you involve a bridge, you may hide the fact that you use tor from
a local authority, but you can't hide this fact from an endpoint.
Yes we can hide that fact from endpoints. at least we can prevent them
use an automated system to instantly find out the answer like today.
Post by s***@quantentunnel.de
Thats all, TBB is limiting that to https, if you use http you
become vulnerable against malicious exit nodes.
Tor is not perfect but still we can rely on it.
Post by s***@quantentunnel.de
So, please forget about hiding the fact that you use tor, by using
tor, from an endpoint - it won't work.
If you give us only one practical example that let destination sites
automatically separate TBB from vanilla Firefox or safari then we
forget about it but don't try throw your fallacies about what global
adversaries can do because nobody expect Tor to be perfect.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
s***@quantentunnel.de
2015-10-03 20:51:34 UTC
Permalink
Post by behnaz Shirazi
If we use a socks proxy server to talk with destination instead of a
private Tor exit node then such an attack becomes as dangerous as when
you are using a detectable TBB over a public Tor exit node because the
number of socks proxies available out there won't be less than public
Tor exit nodes today.
Actually, you are much easier to differentiate for an adversary
since you use tor in combination with socks proxies, you stand out
and now no longer belong in the group of the merry tor users. You have
done an advesary actually a favor. Plus you induce more latency into your
connections, which makes it easier to induce or deduce addional signal
from your connections and makes you even more distinguishable.

A exit-, site operator or a cdn can observe that latency and
clearly differentiate that behavior from tor and regular users.
They'll tag you "slowpoke on an open proxy". If they hire me, I'd
explain to them, how they can ban or tarpit you, if you annoy
them too much so they provide better services to their honest
visitors.

Tor protects you from all that by using different circuits, with
different latencies which results in different exits that needs
much more effort to observe and tag indivdual behavior.

You completly subvert that protection, since you always use a
proxy or maybe a series of proxies, or an exclusive exit, no matter
which destination, you have constant endpoints, if you prefer a
bridge and obfuscation, you may also attach attributes to your
connetction that may be observable (haven't worked with bridges
yet, I leave them for the people who need them). Maybe next
summer holiday.

Your overreliance and misplaced trust in open proxies sticks
properties to your tor connections you don't want. A clever adversary
will attack you from the open proxy due to previouls accumulated
usage patterns. If you try to circumvent exit policies, a
smart proxy operator will downgrade or MITM you.

He may deny you updates for TBB when you need them, using his proxies
he may drop an exploitkit and ransomware on you.

To make it short, instead of ~999 possible exits you rely on one, or
few. If you addionally try to obfuscate TBB, congratulations, you are
pretty unique, and you won't notice in any fingerprint tools, since they
don't correlate and accmulate all that stuff that the open proxy can
learn from you.

On the list of historically stupid things to do with Tor, I rank you
second place, behind the dude who tried to give out his "pre-warmed keys"
and beating the folks that try to torrent with tor, to it.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
behnaz Shirazi
2015-10-06 22:40:06 UTC
Permalink
Post by s***@quantentunnel.de
Post by behnaz Shirazi
If we use a socks proxy server to talk with destination instead of a
private Tor exit node then such an attack becomes as dangerous as when
you are using a detectable TBB over a public Tor exit node because the
number of socks proxies available out there won't be less than public
Tor exit nodes today.
Actually, you are much easier to differentiate for an adversary
since you use tor in combination with socks proxies, you stand out
and now no longer belong in the group of the merry tor users. You have
done an advesary actually a favor. Plus you induce more latency into your
connections, which makes it easier to induce or deduce addional signal
from your connections and makes you even more distinguishable.
A exit-, site operator or a cdn can observe that latency and
clearly differentiate that behavior from tor and regular users.
They'll tag you "slowpoke on an open proxy". If they hire me, I'd
explain to them, how they can ban or tarpit you, if you annoy
them too much so they provide better services to their honest
visitors.
high latency doesn't mean proxy, a lots of gamers have high latency
problem just because of their poor ISP and many others complain about
slow ping because of their heavy Firewalls. even if destination
presume that a proxy or VPN is used, still in many different cases it
is much better than detecting that user is behind Tor. I remember some
NSA documents about targeting anyone who simply surfed Linux journals
but they didn't the same thing with Apple/Microsoft gossip sites. A
little bit change can make a lot of difference...
Post by s***@quantentunnel.de
To make it short, instead of ~999 possible exits you rely on one, or
few. If you addionally try to obfuscate TBB, congratulations, you are
pretty unique, and you won't notice in any fingerprint tools, since they
don't correlate and accmulate all that stuff that the open proxy can
learn from you.
why you think we are limited to less than ~999 possible proxy?
Post by s***@quantentunnel.de
On the list of historically stupid things to do with Tor, I rank you
second place, behind the dude who tried to give out his "pre-warmed keys"
and beating the folks that try to torrent with tor, to it.
We have nothing to lose. you are saying that if we fail they detect
that we used Tor but with current TBB setup they instantly detect that
we are using Tor.

Today all TBBs return same fingerprint, we just replace that value
with what iphones generally have. You might say socks proxy part for
exiting a Tor exit opens a new door for attackers.

When you normally use Tor your route is
Post by s***@quantentunnel.de
EntryGuard>MiddleRelay>ExitNode>DestinationSite and DestinationSite
is an IP address that doesn't change but ExitNode randomly changes
based on what is available. When we use a proxy/VPN before
DestinationSite we talk to DestinationSite with same IP address until
session fully ends, as any normal user always do. We want make sure
that this property can't deanonymize user itself or other Tor users.

1-as I said UnidentifiableMode is not made for everyday life, we only
use it for custom plans so we shouldn't open other tabs when doing
that, that means we won't open a real facebook profile in a different
session while in another session try contact with Guardian. This
manner foils associating anonymous sessions to unanonymous sessions.
note that if UnidentifiableMode fails to work as we expect, it only
makes user detectable and distinguishable from other users, it doesn't
leak the real location. nothing to lose here. If you are worry that
attacker look at entry-exit points of connection for correlating
traffic and deanonymizing the location then it can happen even if you
don't use any proxy to talk with destination, when your exit changes
frequently there is even more chance for attacker to finally get you
at one of his compromised exit points to deanonymize your circuit by
timing attacks.

in future versions we can let user import several proxies and use each
one for every different DestinationSite. So we can search google or
see cat videos while in a different tab write a blog post.

2-Whether undetectable TBB fails or win, it doesn't hurt detectable
TBB users if population of detectable TBB users remain almost as large
as it is today. According to what UnidentifiableMode is created for,
invisible users will be the minority in the Tor community hence
detectable TBB users won't be effected by undetectable TBB users.
Post by s***@quantentunnel.de
Post by behnaz Shirazi
If you give us only one practical example that let destination sites
automatically separate TBB from vanilla Firefox or safari
Assuming we're talking about an unmodified TBB? I'd start by trying to
ascertain whether no-script is enabled. Working out whether HTTPS
Everywhere is enabled should be fairly trivial too. There are, of course,
plenty of people who run those in combination outside of TBB, but it's a
reasonable starting point for narrowing things down.
How difficult is disabling Noscript or HTTPSEverywhere? Before
activating UnidentifiableMode we can tell user watch out the address
bar for https sign as they always do in regular browsers and instead
of blocking WebGL or canvas we can intercept calls to canvas read
function and return a normal response (if we are going to impersonate
iphones then that value would be same for everyone as all iphones are
same device)
Post by s***@quantentunnel.de
Interesting.
You should draft this into a proposal, with some visuals of the
interface and experience flows, and submit it to the list in search for
a developer, unless you can bust this out yourself? I can help anyway
that I can. If you are interested, hit me up off-list.
Otherwise, unless there is something more tangible, I feel like people
will keep arguing that Tor is fine as-is :)
if you write it for me i appreciate that :)

Therefore all undetectable users will have same fingerprint. In
ordinary TBB today all users have same fingerprint too but in
undetectable TBB instead of a suspicious Firefox fingerprint that is
black listed everywhere they will look like a natural iphone browser
that is used by many others elsewhere. For the time zone we should use
something more natural, I recommend EST as default for everyone and
allowing users to replace that value with a different common zone if
they needed.

And Tor devs don't need to do anything else. Finding a bridge for
entering the onion network or a socks proxy server to exit the pool is
on users who want hide their Tor from local authorities or destination
websites. They only need fix TBB, I guess by creating an Add-on. And
there is no need to make this Add-on built-in, we can ship it only to
those who want it as an experimental tool like OONI

in torproject's front page in side bar it says “Who Uses Tor?” and
half of those groups need undetectability :))
Post by s***@quantentunnel.de
Post by behnaz Shirazi
using tor to connect
to another semi-public entity (like an open proxy)
The only case, were that makes sense to me is for trolling sites
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Invisible mode have much more importance than bypassing verification
after opening accounts although the most common use case seems to be
bypassing flags. If you wear a mask and try go to shopping it clearly
cause problem but when you try talk to people about state oppression,
a mask put you in serious trouble and hiding your mask from a
government is much more difficult than hiding it from a drug store.
Post by s***@quantentunnel.de
Wasn't Mozilla working on a Firefox which uses Tor for "Private Browsing"?
https://wiki.mozilla.org/Privacy/Roadmap/Tor
If millions of people would use the same Firefox on the same version
with mostly the same browser/javascript behaviour, it would make TBB
obsolete. Wouldn't it make more sense to include those anonymity patches
into the mainline Firefox and make them opt-in if the user uses Private
Browsing?
If 1 billion person use TBB it doesn't mean TBB becomes undetectable.
That Mozilla project have nothing to do with undetectability (I'm
afraid they even don't know what is detectability problem in TBB).
they just want add Tor in private browsing mode for extra security
because current Firefox private mode is snake-oil. In the wiki page
they mention we should fix fingerprinting problem. Their solutions
finally makes their private mode detectable as TBB became.
Post by s***@quantentunnel.de
Post by behnaz Shirazi
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Tor isn't responsible for that, it's a problem between your endpoint
and you, not between you and Tor. I can't say much about specific
services, but ixquick and startpage work flawlessly for me, maybe OP
should stop using open proxies and re-evaluate his situation with TBB
only? May use the "News Identity Button" more often?
For services, that really limit you, you basically limit yourself
to that service, so you are barking up the wrong tree imho.
Tor doesn't entitle you to use a specific service, it provides
an anonymized connection - thats another basic misconception from you
both.
So nothing to really discuss here.
You say that if NSA detect my Tor and automatically hack me then it's
only between me and NSA. Yes you are right but Tor can save me if they
hide me from them at first place.
Post by s***@quantentunnel.de
On another note, you are imposing youself onto a service, that may have
choosen not to work with Tor, maybe you should iterate about that too and
which implications your actions would have to other participants or the
network? I really feel, you both are falling short on that angle.
Google don't care about you. If you disappear they are more happy with
that. However detectability is not only about bypassing flags. I want
solve this problem for security reasons because detection in some
cases is really dangerous. I discussed about it already
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin
behnaz Shirazi
2015-10-06 22:47:48 UTC
Permalink
oh god
Post by s***@quantentunnel.de
Post by behnaz Shirazi
If we use a socks proxy server to talk with destination instead of a
private Tor exit node then such an attack becomes as dangerous as when
you are using a detectable TBB over a public Tor exit node because the
number of socks proxies available out there won't be less than public
Tor exit nodes today.
Actually, you are much easier to differentiate for an adversary
since you use tor in combination with socks proxies, you stand out
and now no longer belong in the group of the merry tor users. You have
done an advesary actually a favor. Plus you induce more latency into your
connections, which makes it easier to induce or deduce addional signal
from your connections and makes you even more distinguishable.
A exit-, site operator or a cdn can observe that latency and
clearly differentiate that behavior from tor and regular users.
They'll tag you "slowpoke on an open proxy". If they hire me, I'd
explain to them, how they can ban or tarpit you, if you annoy
them too much so they provide better services to their honest
visitors.
high latency doesn't mean proxy, a lots of gamers have high latency
problem just because of their poor ISP and many others complain about
slow ping because of their heavy Firewalls. even if destination
presume that a proxy or VPN is used, still in many different cases it
is much better than detecting that user is behind Tor. I remember some
NSA documents about targeting anyone who simply surfed Linux journals
but they didn't the same thing with Apple/Microsoft gossip sites. A
little bit change can make a lot of difference...
Post by s***@quantentunnel.de
To make it short, instead of ~999 possible exits you rely on one, or
few. If you addionally try to obfuscate TBB, congratulations, you are
pretty unique, and you won't notice in any fingerprint tools, since they
don't correlate and accmulate all that stuff that the open proxy can
learn from you.
why you think we are limited to less than ~999 possible proxy?
Post by s***@quantentunnel.de
On the list of historically stupid things to do with Tor, I rank you
second place, behind the dude who tried to give out his "pre-warmed keys"
and beating the folks that try to torrent with tor, to it.
We have nothing to lose. you are saying that if we fail they detect
that we used Tor but with current TBB setup they instantly detect that
we are using Tor.

Today all TBBs return same fingerprint, we just replace that value
with what iphones generally have. You might say socks proxy part for
exiting a Tor exit opens a new door for attackers.

When you normally use Tor your route is
Post by s***@quantentunnel.de
EntryGuard>MiddleRelay>ExitNode>DestinationSite and DestinationSite
is an IP address that doesn't change but ExitNode randomly changes
based on what is available. When we use a proxy/VPN before
DestinationSite we talk to DestinationSite with same IP address until
session fully ends, as any normal user always do. We want make sure
that this property can't deanonymize user itself or other Tor users.

1-as I said UnidentifiableMode is not made for everyday life, we only
use it for custom plans so we shouldn't open other tabs when doing
that, that means we won't open a real facebook profile in a different
session while in another session try contact with Guardian. This
manner foils associating anonymous sessions to unanonymous sessions.
note that if UnidentifiableMode fails to work as we expect, it only
makes user detectable and distinguishable from other users, it doesn't
leak the real location. nothing to lose here. If you are worry that
attacker look at entry-exit points of connection for correlating
traffic and deanonymizing the location then it can happen even if you
don't use any proxy to talk with destination, when your exit changes
frequently there is even more chance for attacker to finally get you
at one of his compromised exit points to deanonymize your circuit by
timing attacks.

in future versions we can let user import several proxies and use each
one for every different DestinationSite. So we can search google or
see cat videos while in a different tab write a blog post.

2-Whether undetectable TBB fails or win, it doesn't hurt detectable
TBB users if population of detectable TBB users remain almost as large
as it is today. According to what UnidentifiableMode is created for,
invisible users will be the minority in the Tor community hence
detectable TBB users won't be effected by undetectable TBB users.
Post by s***@quantentunnel.de
Post by behnaz Shirazi
If you give us only one practical example that let destination sites
automatically separate TBB from vanilla Firefox or safari
Assuming we're talking about an unmodified TBB? I'd start by trying to
ascertain whether no-script is enabled. Working out whether HTTPS
Everywhere is enabled should be fairly trivial too. There are, of course,
plenty of people who run those in combination outside of TBB, but it's a
reasonable starting point for narrowing things down.
How difficult is disabling Noscript or HTTPSEverywhere? Before
activating UnidentifiableMode we can tell user watch out the address
bar for https sign as they always do in regular browsers and instead
of blocking WebGL or canvas we can intercept calls to canvas read
function and return a normal response (if we are going to impersonate
iphones then that value would be same for everyone as all iphones are
same device)
Post by s***@quantentunnel.de
Interesting.
You should draft this into a proposal, with some visuals of the
interface and experience flows, and submit it to the list in search for
a developer, unless you can bust this out yourself? I can help anyway
that I can. If you are interested, hit me up off-list.
Otherwise, unless there is something more tangible, I feel like people
will keep arguing that Tor is fine as-is :)
if you write it for me i appreciate that :)

Therefore all undetectable users will have same fingerprint. In
ordinary TBB today all users have same fingerprint too but in
undetectable TBB instead of a suspicious Firefox fingerprint that is
black listed everywhere they will look like a natural iphone browser
that is used by many others elsewhere. For the time zone we should use
something more natural, I recommend EST as default for everyone and
allowing users to replace that value with a different common zone if
they needed.

And Tor devs don't need to do anything else. Finding a bridge for
entering the onion network or a socks proxy server to exit the pool is
on users who want hide their Tor from local authorities or destination
websites. They only need fix TBB, I guess by creating an Add-on. And
there is no need to make this Add-on built-in, we can ship it only to
those who want it as an experimental tool like OONI

in torproject's front page in side bar it says “Who Uses Tor?” and
half of those groups need undetectability :))
Post by s***@quantentunnel.de
Post by behnaz Shirazi
using tor to connect
to another semi-public entity (like an open proxy)
The only case, were that makes sense to me is for trolling sites
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Invisible mode have much more importance than bypassing verification
after opening accounts although the most common use case seems to be
bypassing flags. If you wear a mask and try go to shopping it clearly
cause problem but when you try talk to people about state oppression,
a mask put you in serious trouble and hiding your mask from a
government is much more difficult than hiding it from a drug store.
Post by s***@quantentunnel.de
Wasn't Mozilla working on a Firefox which uses Tor for "Private Browsing"?
If millions of people would use the same Firefox on the same version
with mostly the same browser/javascript behaviour, it would make TBB
obsolete. Wouldn't it make more sense to include those anonymity patches
into the mainline Firefox and make them opt-in if the user uses Private
Browsing?
If 1 billion person use TBB it doesn't mean TBB becomes undetectable.
That Mozilla project have nothing to do with undetectability (I'm
afraid they even don't know what is detectability problem in TBB).
they just want add Tor in private browsing mode for extra security
because current Firefox private mode is snake-oil. In the wiki page
they mention we should fix fingerprinting problem. Their solutions
finally makes their private mode detectable as TBB became.
Post by s***@quantentunnel.de
Post by behnaz Shirazi
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Tor isn't responsible for that, it's a problem between your endpoint
and you, not between you and Tor. I can't say much about specific
services, but ixquick and startpage work flawlessly for me, maybe OP
should stop using open proxies and re-evaluate his situation with TBB
only? May use the "News Identity Button" more often?
For services, that really limit you, you basically limit yourself
to that service, so you are barking up the wrong tree imho.
Tor doesn't entitle you to use a specific service, it provides
an anonymized connection - thats another basic misconception from you
both.
So nothing to really discuss here.
You say that if NSA detect my Tor and automatically hack me then it's
only between me and NSA. Yes you are right but Tor can save me if they
hide me from them at first place.
Post by s***@quantentunnel.de
On another note, you are imposing youself onto a service, that may have
choosen not to work with Tor, maybe you should iterate about that too and
which implications your actions would have to other participants or the
network? I really feel, you both are falling short on that angle.
Google don't care about you. If you disappear they are more happy with
that. However detectability is not only about bypassing flags. I want
solve this problem for security reasons because detection in some
cases is really dangerous. I discussed about it already
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-ta
s***@quantentunnel.de
2015-10-09 01:11:28 UTC
Permalink
Post by behnaz Shirazi
why you think we are limited to less than ~999 possible proxy?
Sorry, I simply stop here, since we are not talking discussing TBB
or Tor anymore.
Post by behnaz Shirazi
1-as I said UnidentifiableMode is not made for everyday life, we only
use it for custom plans so we shouldn't open other tabs when doing
TBB is exactly that, to give the a privacy aware layman a comprehensible
tool. With that tool comes a set of limitations. Like don't use protocol
XYZ with Tor. The authors, developers and relay operators simply can't
guarantee that i.e. games (which require in most cases elevated priviledges,
depending on operating system) work with Tor or TBB.
Same with instant messaging and video conferences, bittorrent and so on.

What annoys me the most, that you are not even disitnguishing between a
proxy and an exit, so you are either not aware of the subtle
differences or naive.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Spencer
2015-10-12 21:40:44 UTC
Permalink
Hi,
Post by behnaz Shirazi
You should draft this into a proposal...
if you write it for me i appreciate that :)
I will write it with you. Hit me up.
Post by behnaz Shirazi
Yes, but discrimination is unsupported and avoidable.
Discrimination happens between you and your endpoint,
not between you and Tor.
Destinations discriminate against Tor :)
Post by behnaz Shirazi
Can be done without TBB already.
Might be the way to go, and be part of a security behavior protocol
instead of contained in one package, similar to Tails' Unsafe or Portal
Browsers.
Post by behnaz Shirazi
It would be a discussion, if...
Interesting limitations and perspective. Thanks!

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Ben Tasker
2015-10-03 22:01:57 UTC
Permalink
Post by behnaz Shirazi
but if attacker detect that someone is trying to hide
it's identity when entering a powerful vile's email account or when
trying to contact a high risk journalist, that might cost lives.
But if you're doing something (in the adversary's eyes) that serious, it
probably doesn't matter whether they can tell you're using TBB or not.
Either way, they're going to look at ways to identify you. Being one of a
crowd of Tor users likely offers more protection against that than trying
to make it difficult to identify that you're using Tor.
Post by behnaz Shirazi
undetectablizer Add-on is useful for private exit nodes.
The issue I have with the idea of private exits, is that not everyone can
use them. In other words, if you're using one, then you can be (however
loosely) associated with other users of that node. You all got
access/permission somehow, so you are now incredibly reliant on other users
not slipping up, and on the owner/operator not being traced.

If you've simply paid BTC for access, you then have to be very sure you've
not slipped up (simple examples: re-used a wallet, or funded one from fiat
currency).

Personally, I'd prefer a public exit, it's harder to associate users and
there's less room for making costly mistakes.
Post by behnaz Shirazi
There are limited numbers of data requests possible (check out
browserleaks.com or browserspy.dk). We need list all of them and
compare with other browsers to spoof what is different.
Those are a list of the requests we know are differentiators, it doesn't
mean that others won't be discovered, you'd need to gamble that anything
found is publicly disclosed when it's found, rather than kept quiet by an
adversary. What you're essentially asking for is a browser that behaves
like TBB (i.e. the various privacy protections) whilst pretending it
behaves like a Google Nexus (for example). It's not that it'd be impossible
to do, but one tiny mistake or oversight takes you straight back to being
finger-printable, and almost uniquely so if very few are using
Unidentifiable Mode.
Post by behnaz Shirazi
As far as I know you can't fetch installed Add-ons by javascript, it
only works for plugins so it is not detectable either. Detecting
Add-ons is done by side channel attacks, for instance Adblock prevent
certain scripts or Noscript prevent certain objects, attacker can
simply call such elements and find out those Add-ons are already
installed or not.
Yes and no. You can't just run a list of add-ons off using Javascript,
however a fairly simple side-channel attack is to try and load images from
add-ons you care about detecting. If the add-on is installed and has
contentaccessible set (and your path is valid) then it'll load, if not,
it'll fail.

So, you can fairly easily poll for various add-ons. Not sure it'd affect
your add-on, but seemed worth mentioning.
Post by behnaz Shirazi
We just change details a browser return to calls in a way that caller
can't recognize it is telling the truth or not.
How do you do this without breaking certain sites? For example, if my JS
configures absolute positioning based on screen-size (yes, it's a bad way
of doing things, and yes I've seen sites do it) then you reporting back a
600px screen is going to look terrible on a 1280.
Post by behnaz Shirazi
In a public wifi hotspot there is only one IP address and several
clients simultaneously visit different websites. It would be very
difficult for an attacker to find out a private Tor exit node is
actually a Tor exit node
You'd need to be very careful about where your private exit is located. If
it's in a datacentre, then no-one's going to mistake it for a cafe (for
example). An adversary with sufficient resources would also soon be able to
look at data-rates to and from your box, as well as sources - shouldn't
take them long to realise it's communicating with Tor relays.
Post by behnaz Shirazi
Don't forget that it is not
impossible to locate a user if a global adversary observe a big
portion of globe and deanonymize Tor itself but we still trust Tor for
anonymity thus we can trust undetectablizer Add-on in most of cases to
remain unidentifiable either.
True, the difference here being that you're talking about something that
would be happening on a much smaller scale, and attempting to closely
replicate 'normal' fingerprints. A tiny mistake would be enough to
differentiate you from the 'normal' traffic, as well as from the 'standard'
TBB profile.
Post by behnaz Shirazi
Post by Ben Tasker
As others have said though, the aim isn't to hide that you're using Tor
from your destination, and successfully doing so would (IMO) be a pretty
non-trivial task
What? Undetectabilizer Add-on's aim is exactly hiding that we're using
Tor from the destination site.
To be clear - I meant it wasn't Tor's aim.
Post by behnaz Shirazi
Pluggable Transports aim to hide that
we're using Tor from network observers located between user and
entry-guards.
But not to hide that we're using Tor from the destination.
Post by behnaz Shirazi
Making undetectablizer Add-on is a trivial task.
Making it correctly is not trivial, you have no room for mistakes,
otherwise you risk becoming more fingerprintable than vanilla TBB
Post by behnaz Shirazi
If you give us only one practical example that let destination sites
automatically separate TBB from vanilla Firefox or safari
Assuming we're talking about an unmodified TBB? I'd start by trying to
ascertain whether no-script is enabled. Working out whether HTTPS
Everywhere is enabled should be fairly trivial too. There are, of course,
plenty of people who run those in combination outside of TBB, but it's a
reasonable starting point for narrowing things down.

Someone who's suitably motivated will spend far more time and resources
looking at the minute differences in order to build a fingerprint.
--
Ben Tasker
https://www.bentasker.co.uk
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Spencer
2015-10-05 07:25:53 UTC
Permalink
Hi,
Post by behnaz Shirazi
Post by Spencer
Is a 'Natural Fingerprint' like a clearnet fingerprint, in that it
identifies you as
a regular, >non-tor, internet user, making you part of the larger
herd?
I don't understand what do you mean by “clearnet fingerprint” ?
I have been defining fingerprint as any bit of info that can identify
you, which can be any number of things. I have been defining clearnet
fingerprint as the identifying bit of info defining someone as a
clearnet user, such as a common User Agent.
Post by behnaz Shirazi
Fingerprint is generated locally inside the browser, it is about TBB
not the onion routers.
This would be a Tor Browser fingerprint, but I understand you mean
fingerprinting of Tor Browser to differentiate between Tor Browser
users.
Post by behnaz Shirazi
Connecting to a website directly or via a
public Tor exit node as proxy gives one bit of information (true or
false flag) to destination website but we don't include this bit in
the fingerprinting attack.
By choice, though, yeah? It still seems valuable.
Post by behnaz Shirazi
Post by Spencer
I see this as a blocker, as this add-on is most likely detectable, yeah?
As far as I know you can't fetch installed Add-ons by javascript, it
only works for plugins. Detecting
Add-ons is done by side channel attacks.
We just change details a browser return to calls in a way that caller
can't recognize it is telling the truth or not.
of course it
won't cause a detection if user choose a mobile device profile
Interesting.

You should draft this into a proposal, with some visuals of the
interface and experience flows, and submit it to the list in search for
a developer, unless you can bust this out yourself? I can help anyway
that I can. If you are interested, hit me up off-list.

Otherwise, unless there is something more tangible, I feel like people
will keep arguing that Tor is fine as-is :)

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.tor
Spencer
2015-10-05 09:14:11 UTC
Permalink
Hi,
Post by Ben Tasker
The problem you have there, is what to randomize,
The various bits that define your fingerprint.
Post by Ben Tasker
but natural's hard to fake
No need to spoof traffic if using real fingerprint variables.
Post by Ben Tasker
When we're talking about making the browser unidentifiable as TBB, the very
act of having something in the fingerprint that changes to prevent
correlation between sessions provides an avenue by which it can be
I feel like behavior will address the examples for this argument.
Post by Ben Tasker
Post by Spencer
Making people blend into the crowd of regular internet users is best
but
only if we resolve the traffic source; i.e., Tor exits.
That's quite an issue to solve though. [Attackers can] map out Tor
exits...
True, but we can come up with other ideas than using the public Tor
exits.
Post by Ben Tasker
the aim isn't to hide that you're using Tor
from your destination, and successfully doing so would (IMO) be a pretty
non-trivial task
But it is, and I agree :)
Post by Ben Tasker
Those are a list of the requests we know are differentiators, it doesn't
mean that others won't be discovered, you'd need to gamble that anything
found is publicly disclosed when it's found, rather than kept quiet by an
adversary.
But this is the case for everybody everywhere.
Post by Ben Tasker
What you're essentially asking for is a browser that behaves
like TBB (i.e. the various privacy protections) whilst pretending it
behaves like a Google Nexus (for example). It's not that it'd be impossible
to do, but one tiny mistake or oversight takes you straight back to being
finger-printable, and almost uniquely so if very few are using
Unidentifiable Mode.
With the fingerprint, isn't it only valuable over multiple sessions, and
if others aren't also using that same ID?
Post by Ben Tasker
So, you can fairly easily poll for various add-ons. Not sure it'd affect
your add-on, but seemed worth mentioning.
I don't see this being an add-on as much as being in the settings
options (which can probably be detected?) where the User Agent is
located. The User Agent would be a nice way to simplify the various
IDs.

The IDs can be open-source and added to other browsers as a standard way
of providing detectability.

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
s***@quantentunnel.de
2015-10-05 19:50:57 UTC
Permalink
Post by Spencer
The various bits that define your fingerprint.
That makes only sense if you sync your clients requests
to TrackHostExitsExpire, the effect on CDNs that stick
lots of cookies to you, is that what happens to the folks
in the cloudflare thread, any automatic observer will
diagnose these clients requests for a defunct scraper
and force human interaction proof.

Basically, the countermeasure against such behavior is
to stick a cookie with an hash of your fingerprint
to your browser and deny you, as soon as it no longer
matches.

If you try to spoof any plugin, you forget that, the
presence of a plugin is easy to check, lets assume
we spoof the very popular flashplugin (ewww):
The countermeasure is the same as above, a site
gives you some .swf with a obfuscated redirector inside.
Since you only accept the .swf and discard it your
adversary knows that you fake this bits and denies
you again.

As soon as you turn on javascript, nearly every bit
of your browser is easy to verify, and requesting
with user-agent A in the http-header and stating
that appName is B does look a little bit suspicious.
Post by Spencer
No need to spoof traffic if using real fingerprint variables.
If you'd read the TBB design doc, you'd understand that the
choice that was made, using a pretty real and pretty common
user-agent, and some measures were added.
Post by Spencer
I feel like behavior will address the examples for this argument.
The case, that OP describes, is that he is using tor to connect
to another semi-public entity (like an open proxy) and likes
to hide the fact, that he is using Tor/TBB.

The only case, were that makes sense to me is for trolling sites,
that aren't available via Tor anymore, were the preference for
anonymity is less than trolling those sites, or that is the
impression I get.
Post by Spencer
True, but we can come up with other ideas than using the public Tor
exits.
You still can use tor, the standalone OR, and any browser you
like, if you are so unhappy with TBB. The demanded feature makes
absolutly no sense for a TBB usecase or threatmodel.

You will notice, that if you start to do this, you are uniquely
fingerprintable just try to trick the
https://check.torproject.org/ in stating that you are using
TBB while using another browser, lets say Chrome, with
enabled scripts.

You fail to understand that TBB is a convenient solution,
that is build so humans can circumvent censorship and
achieve a pretty high degree in anonymity while using Tor.

If you really must use non-tor exits, for whatever reason,
access them as a hidden-service, that makes much more sense.
If you can, for example, use only bridges and like to use
a vpn to achieve a high degree of privacy to a given endpoint.

But since OP uses open proxies, I really doubt he wants/needs some
of the features that Tor actually provides. ;)
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Spencer
2015-10-05 22:47:35 UTC
Permalink
Hi,
Post by s***@quantentunnel.de
Post by Spencer
The various bits that define your fingerprint.
Basically, the countermeasure against such behavior is
to stick a cookie with an hash of your fingerprint
to your browser and deny you, as soon as it no longer
matches.
Yes, but discrimination is unsupported and avoidable.
Post by s***@quantentunnel.de
If you try to spoof
No spoof.
Post by s***@quantentunnel.de
If you'd read the TBB design doc,
Quite the presumption :(
Post by s***@quantentunnel.de
you'd understand that the
choice that was made, using a pretty real and pretty common
user-agent, and some measures were added.
And as a result, Tor Browser owns up to its ID with no spoofing, as Tor
Browser users appear a Tor Browser users.
Post by s***@quantentunnel.de
using tor to connect
to another semi-public entity (like an open proxy)
The only case, were that makes sense to me is for trolling sites
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Post by s***@quantentunnel.de
if you are so unhappy with TBB.
Again with the presumptions :(:(
Post by s***@quantentunnel.de
The demanded
Discussed
Post by s***@quantentunnel.de
feature makes
absolutely no sense for a TBB usecase or threatmodel.
Will you link to the use cases and threat models in the documentation?
Post by s***@quantentunnel.de
You fail to understand
Fail often to succeed sooner :)

My thought is that this is being mentioned in multiple places and, if
there is any merit to undetectability, we should challenge it fully to
see; not settle with what we have and use "good enough" as an argument.
I suggested a formal proposal as the next step.

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
aka
2015-10-06 13:22:03 UTC
Permalink
Wasn't Mozilla working on a Firefox which uses Tor for "Private Browsing"?
https://wiki.mozilla.org/Privacy/Roadmap/Tor
If millions of people would use the same Firefox on the same version
with mostly the same browser/javascript behaviour, it would make TBB
obsolete. Wouldn't it make more sense to include those anonymity patches
into the mainline Firefox and make them opt-in if the user uses Private
Browsing?
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
s***@quantentunnel.de
2015-10-06 20:17:22 UTC
Permalink
Post by aka
If millions of people would use the same Firefox on the same version
with mostly the same browser/javascript behaviour, it would make TBB
obsolete. Wouldn't it make more sense to include those anonymity patches
into the mainline Firefox and make them opt-in if the user uses Private
Browsing?
I think Mozilla is much too diverse, one example is API-Keys for major
search engines, that tie you to distributors (like in Linux
Distribution) and so on, TBB has some properties that don't stand out,
it comes with a set of addons like noscript, that have a very specific
approach, that isn't available in mainstream or developer, nightly
editons of Mozilla.

And then there are forks like IceWeasel and other spinoffs. Due to the license,
only Mozilla can brand their Browser Mozilla, so operating system does
matter much more if it comes to Mozilla.

TBB wraps around most of the exposed properties. You can diff the repositories
against eachother, that should give you an idea, how different they are.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Georg Koppen
2015-10-14 08:06:23 UTC
Permalink
Post by aka
Wasn't Mozilla working on a Firefox which uses Tor for "Private Browsing"?
https://wiki.mozilla.org/Privacy/Roadmap/Tor
If millions of people would use the same Firefox on the same version
with mostly the same browser/javascript behaviour, it would make TBB
obsolete. Wouldn't it make more sense to include those anonymity patches
into the mainline Firefox and make them opt-in if the user uses Private
Browsing?
Yes. We (and Mozilla) are working on that. We already got quite an
amount of patches upstreamed. More are coming...

Georg
Spencer
2015-10-21 07:08:51 UTC
Permalink
Hi,
Post by Georg Koppen
Yes. We (and Mozilla) are working on that.
Is there documentation on this?

Wordlife,
Spencer
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
s***@quantentunnel.de
2015-10-06 20:01:46 UTC
Permalink
Post by Spencer
Yes, but discrimination is unsupported and avoidable.
Discrimination happens between you and your endpoint,
not between you and Tor. It may be that a exit discriminates,
if you request a destination port that isn't available
on some exits. Tor tries to find a exit that allows it.

The exit policies are basically there to protect you from doing
stupid things, or to give relay operators the oppurtunity of
running relays in environments that impose restrictions on them.

I operate some little meshy public wifi for homeless people and I have
the same restrictions in place, less cleartext protocols and you can't
use smtp on port 25. Since I offer only locationbased access to
"proven" homeless people, I have less complications.

The Tor-Network, basically exonerates itself, without compromising the
users anonymity.
Post by Spencer
Post by s***@quantentunnel.de
If you try to spoof
No spoof.
Well, than lets call it masquerading. You just add bits to the
fingerprint occansionally: Bad idea. Can be done without TBB already.
Post by Spencer
Post by s***@quantentunnel.de
If you'd read the TBB design doc,
Quite the presumption :(
Well, you understand the rationale behind the decison the TBB
developers made and I don't need to elaborate.
Post by Spencer
And as a result, Tor Browser owns up to its ID with no spoofing, as Tor
Browser users appear a Tor Browser users.
Yeah, and that is awesome, because I can clearly distinguish between
Tor Users and defunct scrapers, and Tor-Users that are using
proxy chains or proxy cascades, to circumvent policies that the
exit-operators/Tor impose on them. Also awesome for me, and for you
too, in case you acciddenlty use cleartext protocols.
Post by Spencer
Or using the internet. What if the OP is tired of being rejected from
visiting sites due to IP badlists and uses said proxy to appear like a
clearnet user so as not to be restricted. Google products (except for
Google Images) require this. Ix Quick and Startpage feature this.
Tor isn't responsible for that, it's a problem between your endpoint
and you, not between you and Tor. I can't say much about specific
services, but ixquick and startpage work flawlessly for me, maybe OP
should stop using open proxies and re-evaluate his situation with TBB
only? May use the "News Identity Button" more often?

For services, that really limit you, you basically limit yourself
to that service, so you are barking up the wrong tree imho.
Tor doesn't entitle you to use a specific service, it provides
an anonymized connection - thats another basic misconception from you
both.

So nothing to really discuss here.
Post by Spencer
Discussed
It would be a disccsusion, if it would present something.
You, both, basically annoy/complain or insist without presenting
anything at all. There are no technical specifics neither any argument,
theory, proposal or proof that your basic idea to implement
a array of changes into TBB gives anynody any advantage,
it could be discussed like this (that is what I added earlier):

"By syncing the User-Agent to TrackHostExitsExpire we can further
thwart detection rates for TBB's http requests. Find a attached a
patch for the plugin, that communicates state-information from
the user's cookies, stored in litesql, via the control-port to Tor's
circuit establishing and reuse logic.

Also, included is a patch for TBB that implements behavior and responses
for current mainstream browsers on major operating systems allowing TBB to
exhibit the same behavior when used with TLS and three new javascript
engines, to normalize the internal behavior and thwart timing attacks
against the current."

And I'd argue: Nice proposal, you can still detect Tor by matching the
originating IP against the table of known exit nodes, so there is not
really a benefit to that, it is just adding more crap to the browser.

And you/your co-proponent say: Yeah, we also have and use proxy chains.

As elaborated before that makes you more trackable, and bascially I think
the exit-ports policies are there, because the exit operators put them there,
so why circumvent them? The only result, as many have pointed out, is
less anonymity.

You both are stating: Well we can't look at cat pictures anymore.

That is what I recall. Bascially, no rationale why using proxies.
You can use them without tor, if you don't need the censorship
circumvention property. The result in privacy in relation to the
endpoint is the same.
Post by Spencer
Will you link to the use cases and threat models in the documentation?
Anonymity online and censorship circumvention, the threatmodel is the same
for Tor. FYI, TBB is only a browser that is more hardwired to Tor and a plugin.
If you haven't read the many specs: https://gitweb.torproject.org/
Post by Spencer
Post by s***@quantentunnel.de
You fail to understand
Fail often to succeed sooner :)
The yoda voice in my head says: On failing much he focuses a lot.
I feel like Obi Wan when discussing young Skywalker, and we both know
were that ended.

Aynway, a lame excuse, try being part of the solution instead of the
problem. Bascially you both blame either Tor for something that is a
agreement between you and your endpoint. Or, anonymous folks abuse Tor
with the consequnece you can't access a service via Tor. Which isn't
solvable with pleasantries or easyness.

If you continue that thought, you start argumenting for backdoors in
Tor pretty soon. BTDT.
Post by Spencer
My thought is that this is being mentioned in multiple places and, if
there is any merit to undetectability, we should challenge it fully to
see; not settle with what we have and use "good enough" as an argument.
I suggested a formal proposal as the next step.
The misconception or flaw is, that you believe there is something like
stealth internet, or more stealth internet. You also fail to comprehend
that the detected anonymity is what Tor users want to achieve.

Even with malicous exits, rogue bridges and compromised middles, it is
still pretty hard to corellate traffic from Tor to indivual users.
Most users want exact that property, and are often fine with the
restrictions. On the other hand, there is no need to use Tor 24/7.

I recommend understanding Kerckhoff's Law and Zooko's Trianle,
that methods of being secretive have to work, even if they are
fully understood (by an adversary) and that are situation
wereyou can't have all the properties you want, you choose
the most meaningful.

What Tor and TBB achieve, I know every node in the network,
still all users are anonymous to me. Hidden service names are best
described clunky, but there is lots of potential for distributed,
decentralized approaches with them.

Your idea, may work for a short timeframe, thats the best
case, until an adversary figures out how it works, he will then deny you
again and again, you adding bits to anonymity again and again.

A futile and ill conceived idea, or another perspective on that, all the
easy problems have already been solved. TBB is more or less the icing.

What you both want or trying to achieve and propose is possible by using
Tor with a browser of your choice, lets assume Firefox and Addons that
make little changes, should be perfectly fine for your idea of less anonymity.

You should re-read your Knuth, the part about optimizing and the
prematureness of it, along with the original proposals against
fingerprinting and adding bits to it (what is bascially what you try to do).

Also https://trac.torproject.org/projects/tor has a lot of ideas for
you, basically
https://trac.torproject.org/projects/tor/wiki/org/projects/WeSupportTor
https://trac.torproject.org/projects/tor/wiki/org/doc/ListOfServicesBlockingTor

I'd recommend to write a patch instead of a proposal, if you really find a
solution, but since https://git.torproject.org/tor-browser.git can't be
cloned at the moment I am not doing this.

On another note, you are imposing youself onto a service, that may have
choosen not to work with Tor, maybe you should iterate about that too and
which implications your actions would have to other participants or the
network? I really feel, you both are falling short on that angle.

Cheers.
--
tor-talk mailing list - tor-***@lists.torproject.org
To unsubscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk
Loading...