go-shadowsocks2

A fresh implementation of Shadowsocks in Go.

GoDoc at https://godoc.org/github.com/shadowsocks/go-shadowsocks2/

Features

• SOCKS5 proxy (Including UDP Associate)
• Support for Netfilter TCP redirect (IPv6 should work but not tested)
• UDP tunneling (e.g. relay DNS packets)
• TCP tunneling (e.g. benchmark with iperf3)

Install

go get -u -v github.com/shadowsocks/go-shadowsocks2

Basic Usage

Server

Start a server listening on port 8488 using AEAD_CHACHA20_POLY1305 AEAD cipher with password your-password.

go-shadowsocks2 -s ss://AEAD_CHACHA20_POLY1305:your-password@:8488 -verbose

Client

Start a client connecting to the above server. The client listens on port 1080 for incoming SOCKS5 connections, and tunnels both UDP and TCP on port 8053 and port 8054 to 8.8.8.8:53 and 8.8.4.4:53 respectively.

go-shadowsocks2 -c ss://AEAD_CHACHA20_POLY1305:your-password@[server_address]:8488 \
     -verbose -socks :1080 -u -udptun :8053=8.8.8.8:53,:8054=8.8.4.4:53 \
                              -tcptun :8053=8.8.8.8:53,:8054=8.8.4.4:53

Replace [server_address] with the server's public address.

Advanced Usage

Use random keys instead of passwords

A random key is almost always better than a password. Generate a base64url-encoded 16-byte random key

go-shadowsocks2 -keygen 16

Start a server listening on port 8848 using AEAD_AES_128_GCM AEAD cipher with the key generated above.

go-shadowsocks2 -s :8488 -cipher AEAD_AES_128_GCM -key k5yEIX5ciUDpkpdtvZm7zQ== -verbose

And the corresponding client to connect to it.

go-shadowsocks2 -c [server_address]:8488 -cipher AEAD_AES_128_GCM -key k5yEIX5ciUDpkpdtvZm7zQ== -verbose

Netfilter TCP redirect (Linux only)

The client offers -redir and -redir6 (for IPv6) options to handle TCP connections redirected by Netfilter on Linux. The feature works similar to ss-redir from shadowsocks-libev.

Start a client listening on port 1082 for redirected TCP connections and port 1083 for redirected TCP IPv6 connections.

go-shadowsocks2 -c [server_address]:8488 -cipher AEAD_AES_128_GCM -key k5yEIX5ciUDpkpdtvZm7zQ== \
    -redir :1082 -redir6 :1083

TCP tunneling

The client offers -tcptun [local_addr]:[local_port]=[remote_addr]:[remote_port] option to tunnel TCP. For example it can be used to proxy iperf3 for benchmarking.

Start iperf3 on the same machine with the server.

iperf3 -s

By default iperf3 listens on port 5201.

Start a client on the same machine with the server. The client listens on port 1090 for incoming connections and tunnels to localhost:5201 where iperf3 is listening.

go-shadowsocks2 -c [server_address]:8488 -cipher AEAD_AES_128_GCM -key k5yEIX5ciUDpkpdtvZm7zQ== \
    -tcptun :1090=localhost:5201

Start iperf3 client to connect to the tunneld port instead

iperf3 -c localhost -p 1090

TODO

• Test coverage
• Binary releases for common platforms

Design Principles

The code base strives to

• be idiomatic Go and well organized;
• use fewer external dependences as reasonably possible;
• only include proven modern ciphers;