Emotional Mangling Proxy

What Apple and I both share after this is done

What is EMP

A transparent interface level proxy for TCP packets. This project is designed to work around the loopback limitations on iOS.

How does it work

em_proxy acts as a local WireGuard server listening on loopback (127.0.0.1) that performs packet source/destination address swapping.

It leverages Cloudflare's boringtun userspace WireGuard implementation to understand WireGuard encryption, decrypting incoming UDP packets from the WireGuard VPN app and rewriting IP headers so packets appear from a non-self origin address, acting as a proxy server for loopback relay.

Prerequisites

Building em_proxy locally requires:

• Rust & Cargo (installed via rustup)
• just task runner (brew install just)
• Xcode & Command Line Tools (for xcodebuild and xcrun)

Install the required Apple compilation targets:

rustup target add aarch64-apple-ios
rustup target add aarch64-apple-ios-sim
rustup target add aarch64-apple-darwin

How to build

Generate the Apple XCFramework (libs/EMProxy.xcframework):

just xcframework

Or build individual target static libraries using cargo:

cargo build --release --target aarch64-apple-ios

CI & Publishing Releases

Continuous Integration

Pushes to branches (develop, main, master), pull requests, and tag pushes all trigger GitHub Actions CI to build and verify EMProxy.xcframework.zip.

Publishing a Release

Only pushing a version tag matching v*.*.* will generate and publish a GitHub Release with EMProxy.xcframework.zip, ready for use in Swift Package Manager via .binaryTarget:

.binaryTarget(
    name: "EMProxyFFI",
    url: "https://github.com/SideStore/em_proxy/releases/download/v0.1.0/EMProxy.xcframework.zip",
    checksum: "<sha256-checksum>"
)

To publish a release:

• Push a version tag matching v*.*.* (e.g. v0.1.0):

git tag v0.1.0
git push origin v0.1.0

Note: Updating or force-pushing tags is only allowed for the latest release. Correcting or updating tags for any releases prior to the last release is disallowed and will trigger a build error.

Progress