udphole

Usage

udphole action ip:port

Actions

listen  Start a server that listens for requests and returns the public
        ip and port of the source.
punch   Punch a UDP NAT hole by making a request to a server and prints
        the private and public ip and port in this order.

Build

Install Rust https://www.rust-lang.org/tools/install and run:

cargo build --release

Install

cargo install --path .

Run

Start a server

cargo run listen 0.0.0.0:6094

Any port can be used, 6094 was chosen for example purposes.

Punch a hole

cargo run punch udphole.fly.dev:6094
192.168.0.100:44266 # private ip and port
208.60.21.109:14554 # public ip and port

Docker

Build

docker build -t udphole:local -f Dockerfile .

Listen

docker run --rm \
    -p 6094:6094/udp --name udphole
    udphole:local listen 0.0.0.0:6094

As of 2023-10, it does not work on macOS + colima because currently colima does not expose UDP ports.

Stop listening

docker kill udphole

It is necessary to use docker kill to stop because contro+c is not terminating the process.

Punch

docker run --rm \
    udphole:local punch udphole.fly.dev:6094

Use this command only for testing purpose, it has no practical use because the container is terminated after execution.