iCepa / tun2tor

A rust library to provide a virtual utun interface to Tor

tun2tor

This project will most probably be discontinued.

Have a look at leaf, for something similar, which is written in latest Rust and is way more flexible and stable.

tun2tor is a Rust library that creates a utun (userspace tunnel) interface, and connects it to to a stream-based proxy like tor. It is primarily intended to be embedded in the iCepa project, but it can also be used as a standalone utility.

Currently, only macOS and iOS are supported, although Linux support is almost there.

tun2tor uses tokio for async IO and LwIP for its TCP implementation (for now).

API Documentation

Running

Running tun2tor as a standalone utility is primarily useful for debugging at the moment. Here is how to get it running:

$ git clone --recursive https://github.com/iCepa/tun2tor.git
$ cd tun2tor
$ cargo build
$ sudo RUST_BACKTRACE=1 target/debug/tun2tor

$ brew install tor
$ tor --DNSPort 12345 --AutomapHostsOnResolve 1

Running it requires root privileges in order to create a utun interface. tun2tor is currently hardcoded in main.rs to create an interface with an IP address of 172.30.20.1, look for a SOCKS proxy at 127.0.0.1:9050, and look for a DNS server at 127.0.0.1:12345.

In order to route traffic through the interface, you need to modify the route table:

// Test DNS:
$ sudo route add 8.8.8.8 172.30.20.1
$ dig @8.8.8.8 facebookcorewwwi.onion

// Test data:
$ sudo route add 116.202.120.181 172.30.20.1 // check.torproject.org
$ wget check.torproject.org

Compiling for iOS

# If you use Homebrew:
$ brew install rustup
# (Note: Rust via brew can't give you the iOS targets! So do use Rustup!)

# If not: (See https://rustup.rs)
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

# Add cross-compile targets for iOS:
$ rustup target add aarch64-apple-ios x86_64-apple-ios

# Install cargo-lipo to create universal binaries:
$ cargo install cargo-lipo

# Compile:
$ cargo lipo

# The binary can be found in target/universal/

Creating a header file

(Noted here for reference, in case you extend tun2tor.)

# Install header generator tool.
$ cargo install cbindgen

# Generate:
$ cbindgen --cpp-compat --crate tun2tor --lang C --output tun2tor.h