shadowsocks-libev/doc/shadowsocks-libev.asciidoc

shadowsocks-libev(8)
====================

NAME
----
shadowsocks-libev - a lightweight and secure socks5 proxy

SYNOPSIS
--------
*ss-local*|*ss-redir*|*ss-server*|*ss-tunnel*|*ss-manager*
 [-s <server_host>] [-p <server_port>] [-l <local_port>] [-k <password>]
 [-m <encrypt_method>] [-f <pid_file>] [-t <timeout>] [-c <config_file>]

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

*Shadowsocks-libev* 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.

OPTIONS
-------

-s <server_host>::
Set the server's hostname or IP.

-l <local_port>::
Set the local port number.
+
Not available in server nor manager mode.

-k <password>::
--password <password>::
Set the password. The server and the client should use the same password.

--key <key_in_base64>::
Set the key directly. The key should be encoded with URL-safe Base64.
+
Not available in manager mode.

-m <encrypt_method>::
Set the cipher.
+
*Shadowsocks-libev* accepts 18 different ciphers:
+
aes-128-gcm, aes-192-gcm, aes-256-gcm,
rc4-md5, aes-128-cfb, aes-192-cfb, aes-256-cfb,
aes-128-ctr, aes-192-ctr, aes-256-ctr, bf-cfb,
camellia-128-cfb, camellia-192-cfb, camellia-256-cfb,
chacha20-ietf-poly1305, salsa20, chacha20 and chacha20-ietf.
+
The default cipher is 'chacha20-ietf-poly1305'.
+
If built with PolarSSL or custom OpenSSL libraries, some of
these ciphers may not work.

-a <user_name>::
Run as a specific user.

-f <pid_file>::
Start shadowsocks as a daemon with specific pid file.

-t <timeout>::
Set the socket timeout in seconds. The default value is 60.

-c <config_file>::
Use a configuration file.

-n <number>::
Specify max number of open files.
+
Not available in manager mode.
+
Only available on Linux.

-i <interface>::
Send traffic through specific network interface.
+
For example, there are three interfaces in your device, which is
lo (127.0.0.1), eth0 (192.168.0.1) and eth1 (192.168.0.2).
Meanwhile, you configure *shadowsocks-libev* to listen on 0.0.0.0:8388
and bind to eth1. That results the traffic go out through eth1,
but not lo nor eth0. This option is useful to control traffic in
multi-interface environment.
+
Not available in redir mode.

-b <local_address>::
Specify local address to bind.
+
Not available in server nor manager mode.

-u::
Enable UDP relay.
+
TPROXY is required in redir mode. You may need root permission.

-U::
Enable UDP relay and disable TCP relay.
+
Not available in local mode.

-L <addr:port>::
Specify destination server address and port for local port forwarding.
+
Only available in tunnel mode.

-d <addr>::
Setup name servers for internal DNS resolver (libc-ares).
The default server is fetched from /etc/resolv.conf.
+
Only available in server and manager mode.

--fast-open::
Enable TCP fast open.
+
Not available in redir nor tunnel mode, with Linux kernel > 3.7.0.

--reuse-port::
Enable port reuse.
+
Only available with Linux kernel > 3.9.0.

--no-delay::
Enable TCP_NODELAY.

--acl <acl_config>::
Enable ACL (Access Control List) and specify config file.
+
Not available in redir nor tunnel mode.

--manager-address <path_to_unix_domain>::
Specify UNIX domain socket address.
+
Only available in server and manager mode.

--executable <path_to_server_executable>::
Specify the executable path of `ss-server`.
+
Only available in manager mode.

-v::
Enable verbose mode.

-h|--help::
Print help message.

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

The config file equivalent of command line options is listed as example below.
[frame="topbot",options="header"]
|==========================================================================
| Command line                        | JSON
| -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"
| -l 4321                             | "local_port": "4321"
| -k "PasSworD"                       | "password": "PasSworD"
| -m "aes-256-cfb"                    | "method": "aes-256-cfb"
| -t 60                               | "timeout": 60
| -a nobody                           | "user": "nobody"
| --fast-open                         | "fast_open": true
| --reuse-port                        | "reuse_port": true
| --no-delay                          | "no_delay": true
| --plugin "obfs-server"              | "plugin": "obfs-server"
| --plugin-opts "obfs=http"           | "plugin_opts": "obfs=http"
| -6                                  | "ipv6_first": true
| -n "/etc/nofile"                    | "nofile": "/etc/nofile"
| -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"
| (only in ss-manager's config)       | "port_password": {"1234":"PasSworD"}
|============================================================================

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
....

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}

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