ss如果要使用 salsa20 或 chacha20 或 chacha20-ietf 算法，需要安装 libsodium ，否则就算在config.json里面设置成chacha20也会提示method not supported.
centos：
yum -y groupinstall "Development Tools"
wget https://github.com/jedisct1/libsodium/releases/download/1.0.11/libsodium-1.0.11.tar.gztar xf libsodium-1.0.11.tar.gz && cd libsodium-1.0.11./configure && make -j2 && make install
echo /usr/local/lib >/etc/ld.so.conf.d/usr_local_lib.confldconfig
ubuntu/debian：
apt-get install build-essential
wget https://github.com/jedisct1/libsodium/releases/download/1.0.11/libsodium-1.0.11.tar.gztar xf libsodium-1.0.11.tar.gz && cd libsodium-1.0.11./configure && make -j2 && make installldconfig
如果曾经安装过旧版本，亦可重复用以上步骤更新到最新版，仅1.0.4或以上版本支持chacha20-ietf