# ss-redir(1)

## NAME

ss-redir - shadowsocks client as transparent proxy, libev port

## SYNOPSIS

ss-redir [-AuUv] [-h|--help] [-s <server_host>] [-p <server_port>] [-l <local_port>] [-k <password>] [-m <encrypt_method>] [-f <pid_file>] [-t <timeout>] [-c <config_file>] [-b <local_address>] [-a <user_name>] [-n <nofile>] [--mtu <MTU>]

## 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. `ss-redir`(1) works as a transparent proxy on local machines to proxy TCP traffic and requires netfilter’s NAT module. For more information, check out `shadowsocks-libev`(8) and the following EXAMPLE section.

## OPTIONS

-s <server_host>

  Set the server’s hostname or IP.

-p <server_port>

  Set the server’s port number.

-l <local_port>

  Set the local port number.

-k <password>

  Set the password. The server and the client should use the same password.

-m <encrypt_method>

  Set the cipher.

  Shadowsocks-libev accepts 21 different ciphers:

  table, rc4, 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, cast5-cfb, des-cfb, idea-cfb, rc2-cfb, seed-cfb, salsa20, chacha20 and chacha20-ietf.

  The default cipher is table.

  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.

  Refer to `shadowsocks-libev`(8) CONFIG FILE section for more details.

-n <number>

  Specify max number of open files.

  Only available on Linux.

-b <local_address>

  Specify local address to bind.

-u

  Enable UDP relay.

  TPROXY is required in redir mode. You may need root permission.

-U

  Enable UDP relay and disable TCP relay.

-A

  Enable onetime authentication.

--mtu <MTU>

  Specify the MTU of your network interface.

--mptcp

  Enable Multipath TCP.

  Only available with MPTCP enabled Linux kernel.

-v

  Enable verbose mode.

-h|--help

  Print help message.

## EXAMPLE

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

    # Create new chain
    root@Wrt:~# iptables -t nat -N SHADOWSOCKS

    # Ignore your shadowsocks server's addresses
    # It's very IMPORTANT, just be careful.
    root@Wrt:~# 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.
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 0.0.0.0/8 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 10.0.0.0/8 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 127.0.0.0/8 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 169.254.0.0/16 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 172.16.0.0/12 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 192.168.0.0/16 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 224.0.0.0/4 -j RETURN
    root@Wrt:~# iptables -t nat -A SHADOWSOCKS -d 240.0.0.0/4 -j RETURN

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

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

    # Apply the rules
    root@Wrt:~# iptables -t nat -A PREROUTING -p tcp -j SHADOWSOCKS
    root@Wrt:~# iptables -t mangle -A PREROUTING -j SHADOWSOCKS

    # Start the shadowsocks-redir
    root@Wrt:~# ss-redir -u -c /etc/config/shadowsocks.json -f /var/run/shadowsocks.pid

## SEE ALSO

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

Last updated 2016-09-16 01:30:49 MDT