s5p

SOCKS5 proxy server with Tor and proxy-chain support. Routes connections through configurable chains of SOCKS4, SOCKS5, and HTTP CONNECT proxies.

Features

• SOCKS5 server (RFC 1928)
• Proxy chaining: tunnel through multiple hops in sequence
• Supported hop protocols: SOCKS5, SOCKS4/4a, HTTP CONNECT
• Per-hop authentication (username/password)
• DNS leak prevention (domain names forwarded to proxies, never resolved locally)
• Tor integration (Tor is just another SOCKS5 hop)
• Pure Python, asyncio-based, minimal dependencies

Quick Start

# Install
cd ~/git/s5p
python -m venv .venv && source .venv/bin/activate
pip install -e .

# Run with Tor
s5p -C socks5://127.0.0.1:9050

# Run with a chain: Tor -> external proxy
s5p -C socks5://127.0.0.1:9050,socks5://proxy:1080

# Run with config file
s5p -c config/example.yaml

# Test it
curl --proxy socks5h://127.0.0.1:1080 https://check.torproject.org/api/ip

Configuration

listen: 127.0.0.1:1080
timeout: 10

chain:
  - socks5://127.0.0.1:9050          # Tor
  - socks5://user:pass@proxy:1080    # exit-side proxy
  - http://proxy2:8080               # HTTP CONNECT proxy

CLI Reference

s5p [-c FILE] [-l [HOST:]PORT] [-C URL[,URL,...]] [-t SEC] [-v|-q]

Options:
  -c, --config FILE        YAML config file
  -l, --listen [HOST:]PORT Listen address (default: 127.0.0.1:1080)
  -C, --chain URL[,URL]    Comma-separated proxy chain
  -t, --timeout SEC        Per-hop timeout (default: 10)
  -v, --verbose            Debug logging
  -q, --quiet              Errors only
  -V, --version            Show version

How Chaining Works

Client -> s5p -> Hop1 -> Hop2 -> ... -> HopN -> Destination

s5p connects to Hop1 via TCP, negotiates the hop protocol (SOCKS5/4/HTTP), then over that tunnel negotiates with Hop2, and so on. The final hop connects to the actual destination. Each hop only sees its immediate neighbors.