Zero dependency, small footprint, cross-platform I2P Java Router with GUI, simple tunnel/socks controller and SAM interface

Note that I2P-zero is not a re-implementation of I2P. It uses the exact I2P source code from the official I2P GitHub repository.

I2P-zero is a build script that produces a zero-dependency installation of the official I2P release, and includes a simplified front end interface.

This project will run under Linux, and build native launchers for Linux, MacOS and Windows. The launchers will include the I2P router, a SAM listener, simple tunnel and socks tunnel functionality and a minimal JVM.

Downloads

Download the latest binary releases for Mac/Windows/Linux here: https://github.com/i2p-zero/i2p-zero/releases

GUI Screenshots

Footprint

The zero-dependency distribution sizes are as follows:

OS	Uncompressed size (MB)	Compressed size (MB)	v1.18 Reproducible build SHA-256
Mac	37.9	26.4	6cd886af8492d876f09092ed8554cd8604b04e4df5e260cdd4820bdfe084efd8
Windows	47.5	32.4	49b333b89d3cf749c468270e944070ab60b3dc0a01ceb7f42c4ba6766fc299ba
Linux	61.5	36.3	7901bde9dfc6e75adccfe304a1abb057a5e3c795cec74fdce61d52251aa151ac
Mac GUI	61.2	45.8	090f7fe54f12ce8b6cbd31356ceb28809dece48a4ee4ffd61dd06d26db39b9c9
Windows GUI	69.4	50.6	b899153d6e5506c1bd25dbf3dbb3867370868b35acb5c1d829cd1a5250ec3733
Linux GUI	86.6	56.5	2438c83285ca426e7b06c5709f10b60a9298d28eb7aa0402d6edad70635d17bf

Note: Reproducible builds are currently experimental. Due to JDK differences, Builds on Mac will consistently have different hashes than builds on Linux. Official releases will always be built using Docker.

Building the launchers

All binary releases for Windows, Mac and Linux can be built from either Linux or Mac.

Use the Docker build method for reproducible builds.

To build using Docker on Mac:

First install docker from https://hub.docker.com/editions/community/docker-ce-desktop-mac

containerId=$(docker run -td --rm ubuntu)
docker exec -ti $containerId bash -c  '\
  apt-get update \
  && apt-get -y install git wget zip unzip \
  && git clone https://github.com/i2p-zero/i2p-zero.git \
  && cd i2p-zero && bash bin/build-all-and-zip.sh'
docker cp $containerId:/i2p-zero/dist-zip ./
docker container stop $containerId

To build using Docker on Ubuntu:

sudo apt -y install docker docker.io
systemctl start docker

containerId=$(sudo docker run -td --rm ubuntu)
sudo docker exec -ti $containerId bash -c  '\
  apt-get update \
  && apt-get -y install git wget zip unzip \
  && git clone https://github.com/i2p-zero/i2p-zero.git \
  && cd i2p-zero && bash bin/build-all-and-zip.sh'
sudo docker cp $containerId:/i2p-zero/dist-zip ./
sudo docker container stop $containerId

This will result in a dist-zip directory being copied into the current directory. The dist-zip directory will contain the builds for all platforms.

To build without Docker on Ubuntu:

To build without Docker on a freshly installed Ubuntu system, first ensure git is installed:

sudo apt install git

Then, retrieve this project from git:

git clone https://github.com/i2p-zero/i2p-zero.git

Also note that JDKs for Linux, MacOS and Windows will be downloaded, which will total several hundred megabytes. You may need to ensure your system has zip, unzip and bzip2 installed to run the build script.

Run the bin/build-all-and-zip.sh script, which will in turn call the following scripts:

1. bin/import-packages.sh to retrieve the I2P Java sources, OpenJDK and the Ant build tool

2. bin/build-original-i2p.sh to build the I2P project retrieved from the I2P repository

3. bin/build-launcher.sh to convert the I2P JARs to modules, compile the Java source code in this project, and then use the jlink tool to build zero-dependency platform-specific launchers.

4. bin/zip-all.sh to produce the distribution zip files and display their SHA-256 hashes. Note that reproducible builds are currently a work in progress, and that only builds on Linux will show the same hashes as the official releases.

Running the GUI

To run the Linux router, double-click the app located at dist/linux-gui/router/bin/i2p-zero

To run the MacOS router, double-click the app located at dist/mac-gui/router/i2p-zero.app

For Windows, double-click the app located at dist/win-gui/router/i2p-zero.exe

Running the command line version

To run the Linux router, type:

dist/linux/router/bin/i2p-zero

To run the MacOS router, type:

dist/mac/router/bin/launch.sh

For Windows, run: (note that the Windows build will run in the background and not show a success message)

dist/win/router/i2p-zero.exe

If it launches successfully, you'll see the message:

I2P router launched.
Press Ctrl-C to gracefully shut down the router (or send the SIGINT signal to the process).

Tunnel control

Note that it may take a short while for new tunnels to be set up.

Call the dist/linux/router/bin/tunnel-control.sh script as follows to create and destroy tunnels:

Get the router reachability status. Returns a string such as "Testing", "Firewalled", "Running", "Error"

tunnel-control.sh router.reachability

Find out if the router is running (where "running" means it has warmed up and is allowing I2P connections to be created). Returns "true" or "false"

tunnel-control.sh router.isRunning

Listen for I2P connections and forward them to the specified host and port. Returns the I2P base 32 destination address for the server tunnel created.

Optionally, specify a directory for storing/reading the server key file. If the directory doesn't exist with a file named *.b32.i2p.keys in it, returns a newly created destination address and writes the secret key for the new address to a file called .keys in the specified directory. Otherwise, read the existing secret key from that directory. The server tunnel will listen for I2P connections and forward them to the specified host and port. Note that the base 32 I2P destination address deterministically depends on the contents of the .keys file).

tunnel-control.sh server.create <host> <port> <(optional) directory>

or, if you would like a vanity b32 address for your server tunnel that begins with a 3 character (alphanumeric) prefix, type:

tunnel-control.sh server.create.vanity <host> <port> <directory> <prefix>

If you do not want to specify the directory parameter above, specify none as the directory. Note that this command may take several minutes to complete.

Check the state of a tunnel. Returns "opening" or "open"

tunnel-control.sh server.state <base 32 I2P address> tunnel-control.sh client.state <local port> tunnel-control.sh http.state <local port> tunnel-control.sh socks.state <local port>

Close the tunnel listening for connections on the specified I2P destination address. Returns "OK".

tunnel-control.sh server.destroy <base 32 I2P address>

Create a tunnel that listens for connections on localhost on the specified port and forwards connections over I2P to the specified destination public key.

tunnel-control.sh client.create <I2P destination> <local port>

Close the tunnel listening for connections on the specified port. Returns "OK".

tunnel-control.sh client.destroy <local port>

Create an http proxy (for accessing .i2p web sites), listening on the specified port

tunnel-control.sh http.create <local port>

Destroy the http proxy listening on the specified port

tunnel-control.sh http.destroy <local port>

Create a socks tunnel, listening on the specified port

tunnel-control.sh socks.create <local port>

Destroy the socks tunnel listening on the specified port

tunnel-control.sh socks.destroy <local port>

Destroy all tunnels. Returns "OK"

tunnel-control.sh all.destroy

List all tunnels. Returns JSON string containing information about all tunnels currently in existence

tunnel-control.sh all.list

Start a SAM listener on port 7656. Returns "OK"

tunnel-control.sh sam.create

Get the external port randomly assigned to this router when first run, which the firewall should allow incoming UDP and TCP connections on. Returns the port number.

tunnel-control.sh router.externalPort

Set the bandwidth limit, measured in KBps. Returns "OK".

tunnel-control.sh router.setBandwidthLimitKBps <KBps>

Get the bandwidth limit, measured in KBps

tunnel-control.sh router.getBandwidthLimitKBps

Get bandwidth statistics. Returns a comma separated list of statistics

tunnel-control.sh router.getBandwidthStats

example response:

1sRateInKBps=12.34,1sRateOutKBps=12.34,5mRateInKBps=12.34,5mRateOutKBps=12.34,avgRateInKBps=12.34,avgRateOutKBps=12.34,totalInMB=12.34,totalOutMB=12.34

or, for pleasant viewing on the command line, automatically updating every 2 seconds:

watch "tunnel-control.sh router.getBandwidthStats | tr ',' '\n' | sort"

Get the I2P-zero version

tunnel-control.sh version

example response:

i2p-zero 1.8

Watch the I2P log for messages

tail -f dist/linux/router/i2p.config/wrapper.log

Note on bundled windows launcher.exe executable

There is a bundled resources/launcher.exe file in the source tree. This allows the windows distributable to be built even on a non-windows platform.

#This file can be deterministically recreated by following these steps on a Windows machine:

1. Download AdoptOpenJDK14 from https://github.com/AdoptOpenJDK/openjdk14-binaries/releases/download/jdk14-2020-03-09-04-56/OpenJDK14-jdk_x64_windows_hotspot_2020-03-09-04-56.zip
2. Create a new folder, and place inside the resources/icons.ico file and the router folder from an I2P-zero for Windows GUI build
3. Run `\bin\jpackage.exe --type app-image --icon icons.ico --name i2p-zero -m org.getmonero.i2p.zero.gui/org.getmonero.i2p.zero.gui.Gui --runtime-image router\runtime
4. Run certUtil -hashfile i2p-zero/i2p-zero.exe SHA256 to get the SHA256 hash.
5. This hash should exactly match the SHA256 hash of the resources/launcher.exe file, which should be 3d5d00eeff5cb9d63ea415c593d67f201a7d024b6378d22d702b001e6693a93a