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README.md

shadowsocks-libev

Build Status Snap Status

Intro

Shadowsocks-libev is a lightweight secured SOCKS5 proxy for embedded devices and low-end boxes.

It is a port of Shadowsocks created by @clowwindy, and maintained by @madeye and @linusyang.

Current version: 3.3.2 | Changelog

Features

Shadowsocks-libev is written in pure C and depends on libev. It's designed to be a lightweight implementation of shadowsocks protocol, in order to keep the resource usage as low as possible.

For a full list of feature comparison between different versions of shadowsocks, refer to the Wiki page.

Quick Start

Snap is the recommended way to install the latest binaries.

Install snap core

https://snapcraft.io/core

Install from snapcraft.io

Stable channel:

sudo snap install shadowsocks-libev

Edge channel:

sudo snap install shadowsocks-libev --edge

Installation

Distribution-specific guide


Pre-build configure guide

For a complete list of available configure-time option, try configure --help.

Debian & Ubuntu

Install from repository

Shadowsocks-libev is available in the official repository for following distributions:

  • Debian 8 or higher, including oldstable (jessie), stable (stretch), testing (buster) and unstable (sid)
  • Ubuntu 16.10 or higher
sudo apt update
sudo apt install shadowsocks-libev

For Debian 8 (Jessie) users, please install it from jessie-backports-sloppy: We strongly encourage you to install shadowsocks-libev from jessie-backports-sloppy. For more info about backports, you can refer Debian Backports.

sudo sh -c 'printf "deb http://deb.debian.org/debian jessie-backports main\n" > /etc/apt/sources.list.d/jessie-backports.list'
sudo sh -c 'printf "deb http://deb.debian.org/debian jessie-backports-sloppy main" >> /etc/apt/sources.list.d/jessie-backports.list'
sudo apt update
sudo apt -t jessie-backports-sloppy install shadowsocks-libev

For Debian 9 (Stretch) users, please install it from stretch-backports: We strongly encourage you to install shadowsocks-libev from stretch-backports. For more info about backports, you can refer Debian Backports.

sudo sh -c 'printf "deb http://deb.debian.org/debian stretch-backports main" > /etc/apt/sources.list.d/stretch-backports.list'
sudo apt update
sudo apt -t stretch-backports install shadowsocks-libev

Build deb package from source

Supported distributions:

  • Debian 8, 9 or higher
  • Ubuntu 14.04 LTS, 16.04 LTS, 16.10 or higher

You can build shadowsocks-libev and all its dependencies by script:

mkdir -p ~/build-area/
cp ./scripts/build_deb.sh ~/build-area/
cd ~/build-area
./build_deb.sh

For older systems, building .deb packages is not supported. Please try to build and install directly from source. See the Linux section below.

Note for Debian 8 (Jessie) users to build their own deb packages:

We strongly encourage you to install shadowsocks-libev from jessie-backports-sloppy. If you insist on building from source, you will need to manually install libsodium from jessie-backports-sloppy, NOT libsodium in main repository.

For more info about backports, you can refer Debian Backports.

cd shadowsocks-libev
sudo sh -c 'printf "deb http://deb.debian.org/debian jessie-backports main" > /etc/apt/sources.list.d/jessie-backports.list'
sudo sh -c 'printf "deb http://deb.debian.org/debian jessie-backports-sloppy main" >> /etc/apt/sources.list.d/jessie-backports.list'
sudo apt-get install --no-install-recommends devscripts equivs
mk-build-deps --root-cmd sudo --install --tool "apt-get -o Debug::pkgProblemResolver=yes --no-install-recommends -y"
./autogen.sh && dpkg-buildpackage -b -us -uc
cd ..
sudo dpkg -i shadowsocks-libev*.deb

Note for Debian 9 (Stretch) users to build their own deb packages:

We strongly encourage you to install shadowsocks-libev from stretch-backports. If you insist on building from source, you will need to manually install libsodium from stretch-backports, NOT libsodium in main repository.

For more info about backports, you can refer Debian Backports.

cd shadowsocks-libev
sudo sh -c 'printf "deb http://deb.debian.org/debian stretch-backports main" > /etc/apt/sources.list.d/stretch-backports.list'
sudo apt-get install --no-install-recommends devscripts equivs
mk-build-deps --root-cmd sudo --install --tool "apt-get -o Debug::pkgProblemResolver=yes --no-install-recommends -y"
./autogen.sh && dpkg-buildpackage -b -us -uc
cd ..
sudo dpkg -i shadowsocks-libev*.deb

Configure and start the service

# Edit the configuration file
sudo vim /etc/shadowsocks-libev/config.json

# Edit the default configuration for debian
sudo vim /etc/default/shadowsocks-libev

# Start the service
sudo /etc/init.d/shadowsocks-libev start    # for sysvinit, or
sudo systemctl start shadowsocks-libev      # for systemd

Fedora & RHEL

Supported distributions:

  • Recent Fedora versions (until EOL)
  • RHEL 6, 7 and derivatives (including CentOS, Scientific Linux)

Build from source with centos

If you are using CentOS 7, you need to install these prequirement to build from source code:

yum install epel-release -y
yum install gcc gettext autoconf libtool automake make pcre-devel asciidoc xmlto c-ares-devel libev-devel libsodium-devel mbedtls-devel -y

Install from repository

Enable repo via dnf:

su -c 'dnf copr enable librehat/shadowsocks'

Or download yum repo on Fedora Copr and put it inside /etc/yum.repos.d/. The release Epel is for RHEL and its derivatives.

Then, install shadowsocks-libev via dnf:

su -c 'dnf update'
su -c 'dnf install shadowsocks-libev'

or yum:

su -c 'yum update'
su -c 'yum install shadowsocks-libev'

The repository is maintained by @librehat, any issues, please report here

Archlinux & Manjaro

sudo pacman -S shadowsocks-libev

Please refer to downstream PKGBUILD script for extra modifications and distribution-specific bugs.

NixOS

nix-env -iA nixos.shadowsocks-libev

Nix

nix-env -iA nixpkgs.shadowsocks-libev

Linux

In general, you need the following build dependencies:

  • autotools (autoconf, automake, libtool)
  • gettext
  • pkg-config
  • libmbedtls
  • libsodium
  • libpcre3 (old pcre library)
  • libev
  • libc-ares
  • asciidoc (for documentation only)
  • xmlto (for documentation only)

Notes: Fedora 26 libsodium version >= 1.0.12, so you can install via dnf install libsodium instead build from source.

If your system is too old to provide libmbedtls and libsodium (later than v1.0.8), you will need to either install those libraries manually or upgrade your system.

If your system provides with those libraries, you should not install them from source. You should jump this section and install them from distribution repository instead.

For some of the distributions, you might install build dependencies like this:

# Installation of basic build dependencies
## Debian / Ubuntu
sudo apt-get install --no-install-recommends gettext build-essential autoconf libtool libpcre3-dev asciidoc xmlto libev-dev libc-ares-dev automake libmbedtls-dev libsodium-dev
## CentOS / Fedora / RHEL
sudo yum install gettext gcc autoconf libtool automake make asciidoc xmlto c-ares-devel libev-devel
## Arch
sudo pacman -S gettext gcc autoconf libtool automake make asciidoc xmlto c-ares libev

# Installation of libsodium
export LIBSODIUM_VER=1.0.16
wget https://download.libsodium.org/libsodium/releases/libsodium-$LIBSODIUM_VER.tar.gz
tar xvf libsodium-$LIBSODIUM_VER.tar.gz
pushd libsodium-$LIBSODIUM_VER
./configure --prefix=/usr && make
sudo make install
popd
sudo ldconfig

# Installation of MbedTLS
export MBEDTLS_VER=2.6.0
wget https://tls.mbed.org/download/mbedtls-$MBEDTLS_VER-gpl.tgz
tar xvf mbedtls-$MBEDTLS_VER-gpl.tgz
pushd mbedtls-$MBEDTLS_VER
make SHARED=1 CFLAGS="-O2 -fPIC"
sudo make DESTDIR=/usr install
popd
sudo ldconfig

# Start building
./autogen.sh && ./configure && make
sudo make install

You may need to manually install missing softwares.

FreeBSD

su
cd /usr/ports/net/shadowsocks-libev
make install

Edit your config.json file. By default, it's located in /usr/local/etc/shadowsocks-libev.

To enable shadowsocks-libev, add the following rc variable to your /etc/rc.conf file:

shadowsocks_libev_enable="YES"

Start the Shadowsocks server:

service shadowsocks_libev start

OpenWRT

The OpenWRT project is maintained here: openwrt-shadowsocks.

OS X

For OS X, use Homebrew to install or build.

Install Homebrew:

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Install shadowsocks-libev:

brew install shadowsocks-libev

Windows (MinGW)

To build Windows native binaries, the recommended method is to use Docker:

  • On Windows: double-click make.bat in docker\mingw

  • On Unix-like system:

      cd shadowsocks-libev/docker/mingw
      make
    

A tarball with 32-bit and 64-bit binaries will be generated in the same directory.

You could also manually use MinGW-w64 compilers to build in Unix-like shell (MSYS2/Cygwin), or cross-compile on Unix-like systems (Linux/MacOS). Please refer to build scripts in docker/mingw.

Currently you need to use a patched libev library for MinGW:

Notice that TCP Fast Open (TFO) is only available on Windows 10, 1607 or later version (precisely, build >= 14393). If you are using 1709 (build 16299) or later version, you also need to run the following command in PowerShell/Command Prompt as Administrator and reboot to use TFO properly:

    netsh int tcp set global fastopenfallback=disabled

Docker

As you expect, simply pull the image and run.

docker pull shadowsocks/shadowsocks-libev
docker run -e PASSWORD=<password> -p<server-port>:8388 -p<server-port>:8388/udp -d shadowsocks/shadowsocks-libev

More information about the image can be found here.

Usage

For a detailed and complete list of all supported arguments, you may refer to the man pages of the applications, respectively.

ss-[local|redir|server|tunnel|manager]

   -s <server_host>           Host name or IP address of your remote server.

   -p <server_port>           Port number of your remote server.

   -l <local_port>            Port number of your local server.

   -k <password>              Password of your remote server.

   -m <encrypt_method>        Encrypt method: rc4-md5,
                              aes-128-gcm, aes-192-gcm, aes-256-gcm,
                              aes-128-cfb, aes-192-cfb, aes-256-cfb,
                              aes-128-ctr, aes-192-ctr, aes-256-ctr,
                              camellia-128-cfb, camellia-192-cfb,
                              camellia-256-cfb, bf-cfb,
                              chacha20-ietf-poly1305,
                              xchacha20-ietf-poly1305,
                              salsa20, chacha20 and chacha20-ietf.
                              The default cipher is chacha20-ietf-poly1305.

   [-a <user>]                Run as another user.

   [-f <pid_file>]            The file path to store pid.

   [-t <timeout>]             Socket timeout in seconds.

   [-c <config_file>]         The path to config file.

   [-n <number>]              Max number of open files.

   [-i <interface>]           Network interface to bind.
                              (not available in redir mode)

   [-b <local_address>]       Local address to bind.
                              For servers: Specify the local address to use 
                              while this server is making outbound 
                              connections to remote servers on behalf of the
                              clients.
                              For clients: Specify the local address to use 
                              while this client is making outbound 
                              connections to the server.

   [-u]                       Enable UDP relay.
                              (TPROXY is required in redir mode)

   [-U]                       Enable UDP relay and disable TCP relay.
                              (not available in local mode)

   [-L <addr>:<port>]         Destination server address and port
                              for local port forwarding.
                              (only available in tunnel mode)

   [-6]                       Resolve hostname to IPv6 address first.

   [-d <addr>]                Name servers for internal DNS resolver.
                              (only available in server mode)

   [--reuse-port]             Enable port reuse.

   [--fast-open]              Enable TCP fast open.
                              with Linux kernel > 3.7.0.
                              (only available in local and server mode)

   [--acl <acl_file>]         Path to ACL (Access Control List).
                              (only available in local and server mode)

   [--manager-address <addr>] UNIX domain socket address.
                              (only available in server and manager mode)

   [--mtu <MTU>]              MTU of your network interface.

   [--mptcp]                  Enable Multipath TCP on MPTCP Kernel.

   [--no-delay]               Enable TCP_NODELAY.

   [--executable <path>]      Path to the executable of ss-server.
                              (only available in manager mode)

   [-D <path>]                Path to the working directory of ss-manager.
                              (only available in manager mode)

   [--key <key_in_base64>]    Key of your remote server.

   [--plugin <name>]          Enable SIP003 plugin. (Experimental)

   [--plugin-opts <options>]  Set SIP003 plugin options. (Experimental)

   [-v]                       Verbose mode.

Transparent proxy

The latest shadowsocks-libev has provided a redir mode. You can configure your Linux-based box or router to proxy all TCP traffic transparently, which is handy if you use an OpenWRT-powered router.

# 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 route add local default dev lo table 100
ip rule add fwmark 1 lookup 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

Security Tips

For any public server, to avoid users accessing localhost of your server, please add --acl acl/server_block_local.acl to the command line.

Although shadowsocks-libev can handle thousands of concurrent connections nicely, we still recommend setting up your server's firewall rules to limit connections from each user:

# Up to 32 connections are enough for normal usage
iptables -A INPUT -p tcp --syn --dport ${SHADOWSOCKS_PORT} -m connlimit --connlimit-above 32 -j REJECT --reject-with tcp-reset

License

   Apache License
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   Copyright 2019 Rolando Gopez Lacuata.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       https://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
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Copyright: 2013-2015, Clow Windy <clowwindy42@gmail.com>
           2013-2018, Max Lv <max.c.lv@gmail.com>
           2014, Linus Yang <linusyang@gmail.com>

This program is free software: you can redistribute it and/or modify
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