iptables 端口转发--内网实现上网

iptables -t nat -I POSTROUTING -s 192.168.0.0/24 -j SNAT --to-source 118.x.x.x
iptables -A FORWARD -s 192.168.0.0/24 -j ACCEPT
iptables -A FORWARD -d 192.168.0.0/24 -j ACCEPT