很简单修改 /etc/config/network，添加如下

config rule # allow web
      option name Allow-wan-80
      option target ACCEPT
      option target_port 80
      option proto tcp
      option src wan

config rule # allow ssh， port 22
      option name Allow-wan-ssh
      option target ACCEPT
      option target_port 22
      option proto tcp
      option src wan

重启防火墙/etc/init.d/firewall restart 即可