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6 votes

Security of Tor bridges and Captcha

Any captcha system can be broken by paying people. The captcha has been attacked in the past by a nationstate adversary. The captcha isn't critical to the security of Tor, it does present problems ...
cacahuatl's user avatar
  • 11k
5 votes

problem with obfs4proxy and apparmor (solved)

In your torrc there is the line ClientTransportPlugin obfs4 exec /usr/bin/obfs4proxy --managed Furthermoer the log file states: Jun 08 21:33:05.000 [warn] Could not launch managed proxy ...
Jens Kubieziel's user avatar
  • 8,570
5 votes

find needed details of my own private obfs4 Tor bridge

From the obfs4proxy README: The autogenerated obfs4 bridge parameters are placed in DataDir/pt_state/obfs4_state.json. To ease deployment, the client side bridge line is written to DataDir/...
cacahuatl's user avatar
  • 11k
3 votes
Accepted

tor relay and bridge on one server with two IP addresses

You'd need to run two Tor instances, one for the published relay and the other for the bridge. The important part will be in specifying the correct IP address to bind to and listen on for the ...
cacahuatl's user avatar
  • 11k
3 votes

Tails 3.0 blocks connection to ANY obfs4 bridge

Make sure your time zone and time settings are correct, if your system clock time is off, obfs4 will fail to connect. Tails automatically synchronize time upon start, but sometimes the time ...
Annon35's user avatar
  • 85
2 votes

arm for windows?

No, arm is not available for Windows unless you use Cygwin (ticket).
Damian's user avatar
  • 681
2 votes

problem with obfs4proxy and apparmor (solved)

You could fix your problem with apparmor like this: First open /etc/apparmor.d/abstractions/tor with your favorite editor (with root user) sudo gedit /etc/apparmor.d/abstractions/tor Then change ...
Farbod Ahmadian's user avatar
2 votes

Get Tor bridges via email

COMMANDs: (combine COMMANDs to specify multiple options simultaneously) get bridges Request vanilla bridges. get transport [TYPE] Request a Pluggable Transport by TYPE. get help ...
Kamran salehi's user avatar
2 votes
Accepted

How can I debug Tor connections to see where obfs4 fails?

You can edit your ClientTransportPlugin or ServerTransportPlugin for obfs4proxy to include a -logLevel followed by one of ERROR,WARN,INFO, or DEBUG, an -enableLogging=true flag to enable logging, and ...
cacahuatl's user avatar
  • 11k
2 votes
Accepted

How many custom bridges do I need?

According to this Tor project webpage: Tor will only use one bridge at a time, but it is good to add more than one bridge so you can continue using Tor even if your first bridge becomes unavailable....
m894v5n74v539nm8's user avatar
2 votes
Accepted

What's keeping [insert dictatorship here] from blocking all bridges after first use?

China has already been doing this for some time. Anyone who runs a Tor relay will often receive inbound connections from some random residential looking IP address in China, often with some bizarre ...
cacahuatl's user avatar
  • 11k
2 votes

Bridge to improve anonymity

Yes, having friends running private/unpublished bridge is a way to improve your anonymity, but here is a caveat : use a pluggable transport like obfs3/4 and use bridge key you obtain/give offline, i.e....
Alexey Vesnin's user avatar
  • 6,225
2 votes

Where can I find meek servers?

The meek servers are distributed with Tor Browser. The point of meek is to be difficult to censor not because the bridges are hard to find but because they're hard to distinguish from other traffic. ...
cacahuatl's user avatar
  • 11k
2 votes

Does all bridge users have the same encryption key?

Whenever your client makes a connection to a bridge or any other Tor relay it negotiates an individual key. So this key if different from a key which another client uses and also from a key which your ...
Jens Kubieziel's user avatar
  • 8,570
2 votes
Accepted

Mutliple "bridge" lines in torrc

It will try successive bridges until it is able to use one, starting with the first bridge listed in the torrc. So it can be helpful to use multiple bridge lines, incase one bridge goes down or is ...
cacahuatl's user avatar
  • 11k
2 votes
Accepted

Why isn't my tor starting?

You've appear to have specified ReachableAddresses which means that you've told Tor is can't reach certain destinations, those destinations include the bridges that you've been given so Tor is ...
cacahuatl's user avatar
  • 11k
2 votes

Configure Tor Browser to use a private Bridge

I think this is the documentation that you are looking for: https://www.torproject.org/docs/bridges Understanding A Bridge Configuration Line As an example, when you obtain a bridge from ...
NeverMine17's user avatar
2 votes
Accepted

Optimal configuration for an obfs4 bridge

What numbers to choose for OR and obfs4proxy ports? For an obfs4 bridge I'd recommend: Picking a low numbered port that's used by a common service for obfs4 (it takes a few extra steps to allow ...
cacahuatl's user avatar
  • 11k
2 votes

Is it possible to use meek bridges in orbot?

Yes, Orbot supports meek, specifically meek-lite provided by the obfs4proxy binary that's shipped with Orbot. When you enable bridges (swipe in left, and toggle the 'Bridges' slider to on) it will ...
cacahuatl's user avatar
  • 11k
2 votes

Can I operate a relay and Bridge on same computer?

You could run a relay and bridge on the same computer if you set up 2 instances of tor, but this should not be done. From the FAQ: ... ISPs or governments trying to block access to the Tor network ...
SuperSluether's user avatar
2 votes
Accepted

How to monitor traffic usage on a Tor bridge on Linux?

Take a look at Nyx. That is probably how most relay operators on Linux get their bandwidth and connection information.
Martin's user avatar
  • 181
2 votes

Why is my Tor bridge relay not getting any traffic?

Is your bridge being published as available on https://bridges.torproject.org/? If not, then theres a good chance that nobody know about it. You can also contact the Tor Bridges mailing list for ...
elmerjfudd's user avatar
  • 2,274
2 votes

Tor Bridge Connection

Would the next step be to request private bridges by e-mail? Well you have two options to get bridges: Email [email protected] through Gmail or Riseup. Use MOAT to fetch bridges from the Tor ...
Swangie's user avatar
  • 984
1 vote
Accepted

My ISP is holding all the bridges

Bridges that are not listed in BridgeDB are distributed manually. As such you'd need to know someone or some organisation running such a bridge and contact them to request usage of it and obviously ...
cacahuatl's user avatar
  • 11k
1 vote
Accepted

Tor bridge selection

It'll pick the first one listed (in the order they're defined in the config) that works, this was problematic for Tor Browser's default bridges list, because the first bridge(s) in the list would be ...
cacahuatl's user avatar
  • 11k
1 vote
Accepted

(dis)advantages of using bridges & transports where not strictly needed?

Well, an advantage can be the lesser detectability of your connection/session. Disadvantage is that you must encomplicate the relay descriptor to flag the relay "as the one using obfuscation" and ...
Alexey Vesnin's user avatar
  • 6,225
1 vote
Accepted

Advertise obfs3 Tor bridge on port 80

As per @canonizing comment I installed obfs4 proxy with the following config and it's published: ExitPolicy reject *:* #Bridge config RunAsDaemon 1 ORPort 1234 BridgeRelay 1 ServerTransportPlugin ...
Maxxer's user avatar
  • 246
1 vote
Accepted

Commenting out a wrong bridge

Yes, you need to use SafeLogging 0 for your tor to determine the bridge. After the problem will be fixed - set it to SafeLogging 1 to ensure no leaks in your logs. Here is the official documentation ...
Alexey Vesnin's user avatar
  • 6,225
1 vote

Can the tor initial client to relay or bridge connection be MITM attacked?

Q 1 So I am assuming that this is unencrypted data. Is this correct? There is no "data", this is a TCP handshake, you cannot send data until the 3 way handshake is completed. This is simply ...
cacahuatl's user avatar
  • 11k

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