IEnovyProxy

This is a fork of IPtProxy (https://github.com/tladesignz/IPtProxy) modified to include censorship evading proxies used by Envoy (https://github.com/greatfire/envoy)

currently this includes:

• Lyrebird(https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/lyrebird)
• Snowflake(https://gitlab.torproject.org/tpo/anti-censorship/pluggable-transports/snowflake)
• V2ray
• Hysteria2

We have previously supported (available in git history):

• obfs4proxy
• DNSTT
• Hysteria

While this library was made for use with Envoy, it does not depend on Envoy, and may be useful for other situations. Some of the choices made are specific to our needs, but if others want to use this, we can look in to making it more flexible.

Envoy currently only supports Android, so the iOS/MacOS version is not tested, but should work. None of the changes should cause compatability problems.

In all cases there is a Start() and Stop() (e.g. StartDnstt/StopDnstt) function for each service. There are also accessors to get the port each service is listening on (unused ports are selected at startup time, so these functions are only reliable after the service is started), e.g. DnstttPort(). Obfs4proxy and V2ray use multiple ports, so there are multiple accessors, see the code in IEnvoyProxy/IEnvoyProxy.go for details.

IEnvoyProxy is still a work in progress. Feel free to open issues in this repo if you have questions or comments.

Problems solved in particular are:

• One cannot compile main packages with gomobile. Both PTs are patched to avoid this.
• Proxies are gathered under one roof here, since you cannot have two gomobile frameworks as dependencies, since there are some common Go runtime functions exported, which would create a name clash.
• Free ports to be used are automatically found by this library and returned to the consuming app. You can use the initial values for premature configuration just fine in situations, where you can be pretty sure, they're going to be available (typically on iOS). When that's not the case (e.g. multiple instances of your app on a multi-user Android), you should first start the transports and then use the returned ports for configuration of other components (e.g. Tor).

iOS/macOS

IEnvoyProxy has not been tested on iOS/macOS. It should build and run, but it hasn't been tested. Let us know if you're interested in using this on iOS or macOS.

Android

Installation

IEnvoyProxy is available through JitPack. To install it, simply add the following line to your build.gradle file:

implementation 'org.greatfire:IEnvoyProxy:1.1.0'

And this to your root build.gradle at the end of repositories:

allprojects {
	repositories {
		// ...
		maven { url 'https://jitpack.io' }
	}
}

For newer Android Studio projects created in Android Studio Bumblebee | 2021.1.1 or newer, the JitPack repository needs to be added into the root level file settings.gradle instead of build.gradle:

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
	  // ...
        maven { url 'https://jitpack.io' }
    }
}

Precomiled binaries are also available on the releases page

Getting Started

If you are building a new Android application be sure to declare that it uses the INTERNET permission in your Android Manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="my.test.app">

    <uses-permission android:name="android.permission.INTERNET"/>
    <application ...

Before using IEnvoyProxy you need to specify a place on disk for it to store its state information. We recommend the path returned by Context#getCacheDir():

File fileCacheDir = new File(getCacheDir(), "pt");

if (!fileCacheDir.exists()) fileCacheDir.mkdir();

IPtProxy.setStateLocation(fileCacheDir.getAbsolutePath());

Build

Requirements

You'll need Go 1.18 as a prerequisite.

You will also need Xcode installed when compiling for iOS and an Android NDK when compiling for Android.

The build script needs the gomobile binary and will install it, if not available, yet. However, you'll still need to make it accessible in your $PATH.

So, if it's not already, add $GOPATH/bin to $PATH. The default location for $GOPATH is $HOME/go:

export PATH=$HOME/go/bin/:$PATH` 

iOS

Make sure Xcode and Xcode's command line tools are installed. Then run

rm -rf IEnvoyProxy.xcframework && ./build.sh

This will create an IEnvoyProxy.xcframework, which you can directly drop in your app, if you don't want to rely on CocoaPods.

Android

Make sure that javac is in your $PATH. If you do not have a JDK instance, on Debian systems you can install it with:

apt install default-jdk 

If they aren't already, make sure the $ANDROID_HOME and $ANDROID_NDK_HOME environment variables are set:

export ANDROID_HOME=~/Android/Sdk
export ANDROID_NDK_HOME=$ANDROID_HOME/ndk/$NDK_VERSION

rm -rf IEnvoyProxy.aar IEnvoyProxy-sources.jar && ./build.sh android

This will create an IEnvoyProxy.aar file, which you can directly drop in your app, if you don't want to rely on JitPack.

On certain CPU architectures gobind might fail with this error due to setting a flag that is no longer supported by Go 1.16:

go tool compile: exit status 1
unsupported setting GO386=387. Consider using GO386=softfloat instead.
gomobile: go build -v -buildmode=c-shared -o=/tmp/gomobile-work-855414073/android/src/main/jniLibs/x86/libgojni.so ./gobind failed: exit status 1

If this is the case, you will need to set this flag to build IEnvoyProxy:

export GO386=sse2

Authors

• Steven McDonald, scm@eds.org

for GreatFire https://en.greatfire.org/

IPtProxy Authors:

• Benjamin Erhart, berhart@netzarchitekten.com
• Nathan Freitas
• Annette (formerly Bim)

for the Guardian Project https://guardianproject.info

License

IEnvoyProxy is available under the MIT license. See the LICENSE file for more info.