vpn2socks

A high-performance, Swift-native VPN-to-SOCKS proxy engine for Apple platforms. vpn2socks was created to provide a modern, efficient, and Swift-friendly alternative to traditional tun2socks implementations. While projects like tun2socks are powerful, they are typically written in languages like C or Go, making them difficult to integrate, develop, and maintain within native Swift applications. vpn2socks solves this by offering a pure Swift solution designed for the NetworkExtension framework.

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✅ Core Features

vpn2socks is built around an intelligent TCP connection manager that provides exceptional performance and resource efficiency, especially on memory-constrained mobile devices.

• 🚀 High-Performance TCP Stack: A lightweight, custom TCP/IP stack built from the ground up in Swift to handle TCP connections efficiently within a NetworkExtension environment.

• 🧠 Intelligent & Adaptive Buffer Management:

  • 100ms Fast Shrink: Buffers are aggressively shrunk after just 100ms of inactivity to minimize the app's memory footprint. This is confirmed in logs where connections are rapidly "shrunk to 4096" or "shrunk to 32768" after idle periods.
  • Predictive Expansion: Buffer sizes grow dynamically based on real-time traffic analysis and predictive algorithms. This prevents packet loss by anticipating demand without over-allocating memory.
  • Zero-Latency Recovery: An emergency expansion mechanism instantly resizes buffers upon overflow, ensuring seamless performance during sudden traffic spikes. Logs show the system detecting an [EMERGENCY] Overflow and immediately expanding the buffer from 32KB to 98KB and beyond.

• 📱 Application-Specific Optimizations:

  • YouTube Optimization: Automatically detects YouTube video streams, assigning a dedicated 192KB buffer and handling batched requests to ensure smooth, uninterrupted playback. Log entries frequently show [YouTube] Confirmed batch pattern, demonstrating this awareness.
  • Social Media Awareness: Identifies traffic from major social media apps to adapt buffer sizes for different user activities, such as scrolling through feeds versus watching videos. This ensures a fluid user experience while conserving resources.
  • Differentiated Service: Applies different buffer strategies based on the type of service, with custom minimums for YouTube (48KB), social media (32KB), and general traffic (4KB).

• 🛡️ Robust Memory & Connection Management:

  • Proactively monitors device memory pressure and intelligently trims non-essential connections to maintain stability under critical conditions.
  • Includes a specific bypass for Apple Push Notification Service (APNs) traffic to ensure system notifications are delivered reliably and are not routed through the SOCKS proxy.
  • Includes a performance testing framework to analyze buffer behavior, connection lifecycle, and overall efficiency.

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Why vpn2socks?

For developers working on VPN or proxy tools for iOS and macOS, integrating a tun2socks component can be a significant challenge. vpn2socks offers a compelling alternative:

• Swift Native: Built entirely in modern, memory-safe Swift. This eliminates the need for complex bridging headers and makes the code easier to debug, maintain, and integrate into your existing projects.
• Seamless Integration: Designed specifically for Apple's NetworkExtension framework.
• Optimized for Mobile: The architecture is tailored for the resource constraints of mobile devices, with a strong focus on minimizing memory and battery consumption.
• No External Dependencies: Avoids the complexities of compiling and linking C or Go libraries for multiple Apple architectures.

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How to Use

For a complete example of how to integrate and use vpn2socks, please refer to the SilentPass VPN for iOS project:

SilentPass VPN for iOS