shadowsocks-libev/doc/shadowsocks-c.md

\page shadowsocks-c shadowsocks-c

\brief a lightweight and secure socks5 proxy

\section overview_synopsis SYNOPSIS

ss-local [options]

ss-server [options]

ss-tunnel [options]

ss-redir [options]

ss-manager [options]

ss-nat [options]

\section overview_description DESCRIPTION

shadowsocks-c is a lightweight and secure socks5 proxy. It is a port of the original shadowsocks created by clowwindy. shadowsocks-c is written in pure C and takes advantage of libuv to achieve both high performance and low resource consumption.

shadowsocks-c consists of five components. One is ss-server(1) that runs on a remote server to provide secured tunnel service. ss-local(1) and ss-redir(1) are clients on your local machines to proxy traffic(TCP/UDP or both). ss-tunnel(1) is a tool for local port forwarding.

While ss-local(1) works as a standard socks5 proxy, ss-redir(1) works as a transparent proxy and requires netfilter's NAT module. For more information, check out the EXAMPLE section.

ss-manager(1) is a controller for multi-user management and traffic statistics, using UNIX domain socket to talk with ss-server(1). Also, it provides a UNIX domain socket or IP based API for other software. About the details of this API, please refer to the PROTOCOL section.

\section overview_options OPTIONS

ss-local(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

ss-server(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

ss-tunnel(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

ss-redir(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

ss-manager(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

ss-nat(1) See this command's generated SYNOPSIS and OPTIONS for its accepted arguments.

\section overview_config_file CONFIG FILE

The config file is written in JSON and easy to edit.

The config file equivalent of command line options is listed as examples below.

• -s some.server.net: "server": "some.server.net"
• -s some.server.net -p 1234 (client): "server": "some.server.net:1234"
• -p 1234: "server_port": "1234"
• -b 0.0.0.0: "local_address": "0.0.0.0"
• -b 10.0.0.2: "local_ipv4_address": "10.0.0.2"
• -b 2620:129:35::33: "local_ipv6_address": "2620:129:35::33"
• -l 4321: "local_port": "4321"
• -k "PasSworD": "password": "PasSworD"
• -m "aes-256-gcm": "method": "aes-256-gcm"
• -t 60: "timeout": 60
• -a nobody: "user": "nobody"
• --acl "/path/to/acl": "acl": "/path/to/acl"
• --fast-open: "fast_open": true
• --reuse-port: "reuse_port": true
• --no-delay: "no_delay": true
• --max-connections 1024: "max_connections": 1024
• --max-udp-sessions 512: "max_udp_sessions": 512
• --max-dns-queries 1024: "max_dns_queries": 1024 (ss-server and ss-local)
• --printable-salt: "printable_salt": true (ss-local only)
• --plugin "obfs-server": "plugin": "obfs-server"
• --plugin-opts "obfs=http": "plugin_opts": "obfs=http"
• -6: "ipv6_first": true
• -n 1024: "nofile": 1024
• -d "8.8.8.8": "nameserver": "8.8.8.8"
• -L "somedns.net:53": "tunnel_address": "somedns.net:53"
• -u: "mode": "tcp_and_udp"
• -U: "mode": "udp_only"
• no "-u" nor "-U" options (default): "mode": "tcp_only"
• -T: "tcp_tproxy": true
• (only in ss-manager's config): "port_password": {"1234":"PasSworD"} | \section overview_example EXAMPLE

ss-redir requires netfilter's NAT function. Here is an example:

# Create new chain
iptables -t nat -N SHADOWSOCKS
iptables -t mangle -N SHADOWSOCKS

# Ignore your shadowsocks server's addresses
# It's very IMPORTANT, just be careful.
iptables -t nat -A SHADOWSOCKS -d 123.123.123.123 -j RETURN

# Ignore LANs and any other addresses you'd like to bypass the proxy
# See Wikipedia and RFC5735 for full list of reserved networks.
# See ashi009/bestroutetb for a highly optimized CHN route list.
iptables -t nat -A SHADOWSOCKS -d 0.0.0.0/8 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 10.0.0.0/8 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 127.0.0.0/8 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 169.254.0.0/16 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 172.16.0.0/12 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 192.168.0.0/16 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 224.0.0.0/4 -j RETURN
iptables -t nat -A SHADOWSOCKS -d 240.0.0.0/4 -j RETURN

# Anything else should be redirected to shadowsocks's local port
iptables -t nat -A SHADOWSOCKS -p tcp -j REDIRECT --to-ports 12345

# Add any UDP rules
ip rule add fwmark 0x01/0x01 table 100
ip route add local 0.0.0.0/0 dev lo table 100
iptables -t mangle -A SHADOWSOCKS -p udp --dport 53 -j TPROXY --on-port 12345 --tproxy-mark 0x01/0x01

# Apply the rules
iptables -t nat -A PREROUTING -p tcp -j SHADOWSOCKS
iptables -t mangle -A PREROUTING -j SHADOWSOCKS

# Start the shadowsocks-redir
ss-redir -u -c /etc/config/shadowsocks.json -f /var/run/shadowsocks.pid

\section overview_protocol PROTOCOL

ss-manager(1) provides several APIs through UDP protocol

Send UDP commands in the following format to the manager-address provided to ss-manager(1):

command: [JSON data]

To add a port:

add: {"server_port": 8001, "password":"7cd308cc059"}

To remove a port:

remove: {"server_port": 8001}

To receive a pong:

ping

Then ss-manager(1) will send back the traffic statistics:

stat: {"8001":11370}

\section overview_see_also SEE ALSO

ss-local(1), ss-server(1), ss-tunnel(1), ss-redir(1), ss-manager(1), iptables(8), /etc/shadowsocks-libev/config.json