Onion Pi - Make a Raspberry Pi Into a Anonymizing Tor Proxy(learn.adafruit.com) |
Onion Pi - Make a Raspberry Pi Into a Anonymizing Tor Proxy(learn.adafruit.com) |
You simply shouldn't be using the same machine you use with your real identity with an identity that needs to be anonymous. Even simply things like ntp time sync request can give you away, let alone features like Windows Update (which will definitely give you away since they send a machine ID), browser fingerprinting, evercookies, etc.
Nobody can think of all the different things a machine can send that need to be blocked or reset, which is why you just use a fresh new machine. It is the only way to use Tor safely.
Any device that makes it easier to use Tor with your existing computer is bad for privacy. Especially something being pitched as an 'on/off' switch for instant privacy.
edit: A good setup is the following: install virtualbox, install a light-weight linux distro as a tor router, setup a private and isolated network behind it and then install your 'client' operating system on that private and isolated network in a second virtual machine. Never use the same client machine for long and use the virtual machines snapshot feature to blow away your data every x hours/days (and never use the suspend feature of virtual machine software, it saves your memory (with passwords, keys, etc.) onto disk).
Also there's a more secure version of the RaspberryPi Tor router here: https://github.com/grugq/PORTALofPi
It was submitted by someone last night under a terrible title, so it died a sad death in the "new" page.
I'd really like to hear more about this one.
Murdoch's hot-or-not required a lot more than an ntp sync request and was concerned with identifying hidden services.
The exit node or ISP could also forge a response and set the clock a unique amount of time out of sync which can later be identified over a non-anon network.
Whonix, the privacy oriented Linux distribution which uses two virtual machines (an isolating proxy and then a client on a private network) disable NTP by default and require the user to sync time out-of-band because of these concerns. There is a section in their docs about NTP[2]
[1] http://www.reddit.com/r/onions/comments/10usgv/clock_skewing...
[2] http://sourceforge.net/p/whonix/wiki/Advanced%20Security%20G...
Browser Characteristic: bits of identifying information User Agent: 9.43 HTTP_ACCEPT Headers: 19.19 Browser Plugin Details: 21.51+ Time Zone: 7.13 Screen Size and Color Depth: 5.38 System Fonts: 20.51 Are Cookies Enabled?: 0.43 Limited supercookie test: 4.41
I'm a unique snowflake!
Total (assuming independence): 87.99 Word population (log_2): 32.73
The current theory is that these happen when your relay becomes the hidden service directory, or introduction point, for a popular hidden service. So these are basically roving hotspots that move around the network. In the case of the hidden service directory the pain lasts about a day, and in the case of the introduction point, it lasts for some function of the duration of the introduction point (could be a while) and the time that the hidden service descriptor is fresh (15 minutes or so). Based on the logs here, it sounds like it might be the introduction point in these cases.
Here are some tickets to look at:
https://trac.torproject.org/projects/tor/ticket/3825
https://trac.torproject.org/projects/tor/ticket/4862
https://trac.torproject.org/projects/tor/ticket/8950
Also, the switch to the new ntor circuit-level handshake should reduce the cpu requirements for create cells (in addition to being more secure). So once more people have switched to ntor, these hotspots shouldn't be so bad. It is unclear if that's the same as 'shouldn't be bad'. :)
https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposa...
Full context:
https://lists.torproject.org/pipermail/tor-relays/2013-June/...
OT: I looked at adding a TOR proxy to my personal VPS and pretty quickly decided against it* since it's tough to limit the proxy to legitimate traffic. By "legitimate traffic", I mean traffic for people who really need privacy. By "really need", I don't mean Bittorrent (yes, I use it, too, but I'll deal with the consequences), porn, etc.
I'm really not interested in running a bunch of not-mine-but-pisses-off-Comcast traffic on my cable modem, but I'd love to run a TOR proxy. Anyone got any pointers on running an effective, not-annoying proxy?
Back on topic: if I can sort the question of how to limit not-awesome traffic, I'd happily run a TOR exit node on my Linode and I'd buy a Rasperry Pi to run one at home.
If you dont want to handle the stress of dealing with exit traffic run a relay only node:
ORPort 9001
BridgeRelay 1
Exitpolicy reject *:*Timezones and NTP? NTP does not use time zones so I am not sure what that has to do with anything.
Exit nodes forging ntp responses? That is going to be pretty tough. Last time I checked tor has a tcp fetish and ntp is squarely in the udp camp.
I checked the reddit link. Lets skip over the fact that you said "identify a client" and the reddit link is about hidden services. In order to work it requires that the hidden service serves http, serves http over plain ipv4, and is running on a computer that is also a relay. So that is not "simple" but most importantly it has very little to do with ntp requests.
I'm not going to lie, I stopped reading the whonix documentation after the first three paragraphs and i have pasted them below:
Don't wonder... To prevent against time zone leaks, the system clock
inside Whonix was set to UTC. This means it may be a few hours before
or ahead of your host system clock. Do not change!
On the host. If you were a user of TorBOX 0.2.1 or below and removed
NTP, restore it now.
sudo apt-get install ntpd
Edit: I just saw your restatement of your question. Check out the bandwidth management features and set your relay to only allow exit traffic to port 443. More info on the bandwidth management can be found here:
https://trac.torproject.org/projects/tor/wiki/doc/TorFAQ#Wha...
I put "plaintext" in quotes because they can only see what you want to send to the server, which could be encrypted outside of the context of Tor.
Although I think it is illegal to spy on the data you pass as an exit node, a point that is often not said is that by the design of Tor, you are showing some random person the content of all of your requests, which opens up a whole new attack vector for eavesdropping and man-in-the-middle attacks.