112900928939

#!/usr/bin/env bash

# @sacloud-once
# This script will be executed once when startup.
# スタートアップスクリプトの仕様が変更する場合もあるので注意。
# VPSの例: https://vps.sakura.ad.jp/news/startupscripts-end-ubuntu16/

set -ex

apt update -y
apt install ansible -y

echo iptables-persistent iptables-persistent/autosave_v4 boolean true | debconf-set-selections
echo iptables-persistent iptables-persistent/autosave_v6 boolean true | debconf-set-selections
apt install iptables-persistent -y

sed -i -e "s/PermitRootLogin prohibit-password/PermitRootLogin no/" /etc/ssh/sshd_config
sed -i -e "s/#PasswordAuthentication yes/PasswordAuthentication no/" /etc/ssh/sshd_config

service ssh restart

cat << EOL > /etc/iptables/rules.v4
*filter
:INPUT   DROP   [0:0]
:FORWARD DROP   [0:0]
:OUTPUT  ACCEPT [0:0]

-A INPUT -i lo -j ACCEPT

-A INPUT -p tcp --tcp-flags ALL NONE -j DROP
-A INPUT -p tcp ! --syn -m state --state NEW -j DROP
-A INPUT -p tcp --tcp-flags ALL ALL -j DROP
-A INPUT -p icmp --icmp-type echo-request -m hashlimit --hashlimit-name t_icmp --hashlimit 1/m --hashlimit-burst 10 --hashlimit-mode srcip --hashlimit-htable-expire 120000 -j ACCEPT
-A INPUT -p tcp -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p udp --sport 53 -j ACCEPT

-A INPUT -p tcp -m state --syn --state NEW --dport 22 -m hashlimit --hashlimit-name t_sshd --hashlimit 1/m --hashlimit-burst 10 --hashlimit-mode srcip --hashlimit-htable-expire 120000 -j ACCEPT

-A INPUT -p tcp --dport 80   -j ACCEPT
-A INPUT -p tcp --dport 443  -j ACCEPT

COMMIT
EOL

cat << EOL > /etc/iptables/rules.v6
*filter
:INPUT DROP [0:0]
:FORWARD DROP [0:0]
:OUTPUT DROP [0:0]
COMMIT
EOL

netfilter-persistent reload