nginx仅允许CloudFlore的IP_防止暴露源站IP

location / {
  allow   173.245.48.0/20;
  allow   103.21.244.0/22;
  allow   103.22.200.0/22;
  allow   103.31.4.0/22;
  allow   141.101.64.0/18;
  allow   108.162.192.0/18;
  allow   190.93.240.0/20;
  allow   188.114.96.0/20;
  allow   197.234.240.0/22;
  allow   198.41.128.0/17;
  allow   162.158.0.0/15;
  allow   104.16.0.0/13;
  allow   104.24.0.0/14;
  allow   172.64.0.0/13;
  allow   131.0.72.0/22;
  deny    all;
}

CF回源IP地址 https://www.cloudflare.com/ips-v4/#
参考资料 https://www.yunloc.com/502.html
一个生成配置文件的项目 https://github.com/cevin/cloudflare-ip-sync