GreenTunnel is a local proxy that bypasses DPI (Deep Packet Inspection) censorship by fragmenting the TLS ClientHello so the SNI never appears whole in a single packet, and by resolving DNS over encrypted channels (DoH/DoT). It is a ground-up TypeScript rewrite of the original GreenTunnel, fixing numerous bugs from v2 (backpressure, timeouts, HTTP framing corruption, DNS cache expiry, system proxy crash safety). The repository is a monorepo containing a core engine library, a CLI tool (`gt`), and an Electron desktop app. The engine implements a full HTTP/HTTPS proxy with TLS fragmentation, HTTP request rewriting (absolute-form to origin-form), a caching DNS resolver with TTL-based expiration and in-flight deduplication, and a system-proxy management layer with snapshot/restore and crash recovery. The desktop app provides a 340px frameless window with a live log panel (virtual list), tray integration, and non-intrusive advocacy prompts. The codebase is exceptionally well-documented (CLAUDE.md serves as the authoritative design document), uses modern Node.js features (parseArgs, styleText, pipeline), and has a strong emphasis on correctness and edge-case handling (e.g., stranded proxy detection, HTTP framing awareness, signal handling for clean shutdown).
The Global Socket Toolkit (gsocket) is a secure networking utility suite that enables TCP connections across NATs and firewalls without requiring any inbound ports. It achieves this by relaying traffic through a free cloud-based relay network (GSRN) and encrypting the session end-to-end using SRP (RFC 5054) with AES-256 and a 4096-bit prime. The project provides a core library (`libgsocket`) that abstracts the relay protocol, and several command-line tools: `gs-netcat` (a netcat-like tool for data transfer, reverse shells, port forwarding, and SOCKS proxies), `gs-sftp` (SFTP through the relay), `gs-mount` (sshfs mounting), and `blitz` (bulk file transfer). It also includes a `LD_PRELOAD`-based interposition library (`gsocket_dso`) that can transparently redirect existing network applications through the relay. The architecture is client-server with a relay network; the client establishes a connection to the relay using a shared secret token, and the server connects to the same token, allowing the relay to bridge the two. The codebase is written in C and Bash, with autotools build system, extensive cross-platform support (Linux, macOS, FreeBSD, OpenBSD, Solaris, Cygwin, OpenWRT), and CI/CD pipelines for publishing static binaries. It is a dual-use tool: it can be used for legitimate remote administration, secure file transfer, and privacy, but also includes documented patterns for hidden reverse shells and persistence, which introduces security and maintenance risks.