swgp-go

🐉 Simple WireGuard proxy with minimal overhead for WireGuard traffic.

Proxy Modes

1. Zero overhead

The first 16 bytes of all packets are encrypted using an AES block cipher. The remainder of handshake packets (message type 1, 2, 3) are also randomly padded and encrypted using XChaCha20-Poly1305 to blend into normal traffic.

2. Paranoid

Pad all types of packets without exceeding MTU, then encrypt the whole packet using XChaCha20-Poly1305. We pad data packets because:

• The length of a WireGuard data packet is always a multiple of 16.
• Many IPv6 websites cap their outgoing MTU to 1280 for maximum compatibility.

Configuration Examples

All configuration examples and systemd unit files can be found in the docs directory.

swgp-go uses the same PSK format as WireGuard. A PSK can be generated using wg genpsk or openssl rand -base64 32.

Make sure to use the right MTU for both server and client. To encourage correct use, swgp-go disables IP fragmentation and drops packets that are bigger than expected.

1. Server

In this example, swgp-go runs a proxy server instance on port 20220. Decrypted WireGuard packets are forwarded to [::1]:20221.

{
    "servers": [
        {
            "name": "server",
            "proxyListen": ":20220",
            "proxyMode": "zero-overhead",
            "proxyPSK": "sAe5RvzLJ3Q0Ll88QRM1N01dYk83Q4y0rXMP1i4rDmI=",
            "proxyFwmark": 0,
            "wgEndpoint": "[::1]:20221",
            "wgFwmark": 0,
            "mtu": 1500
        }
    ]
}

2. Client

In this example, swgp-go runs a proxy client instance on port 20222. Encrypted proxy packets are sent to the proxy server at [2001:db8:1f74:3c86:aef9:a75:5d2a:425e]:20220.

{
    "clients": [
        {
            "name": "client",
            "wgListen": ":20222",
            "wgFwmark": 0,
            "proxyEndpoint": "[2001:db8:1f74:3c86:aef9:a75:5d2a:425e]:20220",
            "proxyMode": "zero-overhead",
            "proxyPSK": "sAe5RvzLJ3Q0Ll88QRM1N01dYk83Q4y0rXMP1i4rDmI=",
            "proxyFwmark": 0,
            "mtu": 1500
        }
    ]
}

License

AGPLv3