#教程# Cloudflare 系统负载超过一定的值时 自动切换5秒盾脚本

简介

当你的服务器受到CC攻击时，系统负载就会爆增，这时候就可以利用此脚本自动检测系统负载，当压力超过一定的值时就可以切换为” I’m Under Attack! “模式了。

官方地址

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下载脚本

首先到官网下载脚本或者本站下载：

wget https://dl.yunloc.com/Shell/cloudflare-block.sh && chmod +x cloudflare-block.sh

cloudflare-block.sh 脚本：

#!/bin/bash
 
 
# $1 = 1min, $2 = 5min, $3 = 15min
loadavg=$(awk '{printf "%f", $1}' < /proc/loadavg)
 
 
# load is 10, you can modify this if you want load more than 10
maxload=10
 
 
# Configuration API Cloudflare
# Your Global API Key (https://dash.cloudflare.com/profile)
api_key=
# Email of your Cloudflare account
email=
# Zone ID (https://dash.cloudflare.com/_zone-id_/domain.com)
zone_id=
# Default security level when there is no attack, see in readme
default_security_level=high
# Whether to write debug messages to the debug.log file under script dir
debug=0
 
 
basedir=$(dirname "$0")
 
attacked_file=$basedir/attacked
 
[ "$debug" -eq 1 ] && exec > "${logfile:-$basedir/debug.log}"
 
 
# You can put aforementioned config values either in-place
# or in the file named 'config' in the script's directory.
config_file=$basedir/config
[ -e "$config_file" ] && source "$config_file"
 
 
api_set_mode() {
	local mode
	mode=$1
	curl -s -X PATCH "https://api.cloudflare.com/client/v4/zones/$zone_id/settings/security_level" \
		-H "X-Auth-Email: $email" \
		-H "X-Auth-Key: $api_key" \
		-H "Content-Type: application/json" \
		--data "{\"value\":\"$mode\"}" \
	|| echo "Error: failed to set security level to $mode"
}
 
 
# create file "attacked" if doesn't exist
if [ ! -e "$attacked_file" ]; then
	echo 0 > "$attacked_file"
fi
 
 
was_under_attack=$(cat "$attacked_file")
under_attack=$(echo "$loadavg > $maxload" | bc)
 
if [[ "$1" != [01] ]]; then
	echo "Incorrect usage! Please pass either 0 or 1 as an argument"
	exit 1
fi
 
if [ $debug -eq 1 ]; then
	echo "Mode: $1; was under attack: $was_under_attack; now under attack: $under_attack"
	echo "Load average: $loadavg"
fi
 
if [ "$1" -eq 0 ] && [ "$was_under_attack" -eq 0 ] && [ "$under_attack" -eq 1 ]; then
	# attack just started and we want to enable under-attack mode
 
	# Activate protection
	[ "$debug" -eq 1 ] && echo "Activating under-attack mode!"
	echo 1 > "$attacked_file"
	api_set_mode under_attack
 
elif [ "$1" -eq 1 ] && [ "$was_under_attack" -eq 1 ] && [ "$under_attack" -eq 0 ]; then
	# attack just finished (and up to 20 minutes passed since) 
	# and we want to disable under-attack mode
 
	# Disable Protection
	[ "$debug" -eq 1 ] && echo "Leaving under-attack mode!"
	echo 0 > "$attacked_file"
	api_set_mode "$default_security_level"
 
fi
 
exit 0

修改 cloudflare-block.sh 配置：

＃您的 cloudflare API 密钥（https://dash.cloudflare.com/profile）
API_KEY=
＃您的 Cloudflare 帐户的电子邮件
email=
＃Zone ID（https://dash.cloudflare.com/_zone-id_/domain.com）
zone_id=
＃没有攻击时的默认安全级别，请参阅 Cloudflare 帮助文件
default_security_level=high
＃是否将调试消息写入脚本目录下的 debug.log 文件
debug=0

脚本默认的是检测系统负载为 10，启动” I’m Under Attack! “模式，可以根据需要来调整，一般可以简单的设置为你的核心数*1.2 比如你 CPU 是双核的,可以设置为 2.4

maxload= 7

设置定时任务，如果未启用保护，每 1 分钟检查一次，负载高于 7 开启5 秒盾。如果启用保护，则每 20 分钟检查一次，负载降为 7 以下时取消5 秒盾：

*/1 * * * * /root/cloudflare-block.sh 0
*/20 * * * * /root/cloudflare-block.sh 1

总结

Cloudflare是一个非常好用的防御 DDos 和 CC 攻击的工具，免费版本的 Cloudflare 结合 API 可以实现更加灵活的功能，对于普通的防御足够自己使用了。