# Защита интернет канала
cat >> /etc/sysctl.conf <<EOF

# Дудос защиты путем блокировки-
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.secure_redirects = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.netfilter.ip_conntrack_max = 1048576
net.ipv4.tcp_max_tw_buckets = 1440000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_synack_retries = 2
#net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_syncookies = 0
net.ipv4.tcp_max_syn_backlog = 20000
net.ipv4.tcp_fin_timeout = 30
net.ipv4.tcp_keepalive_time = 300
net.ipv4.tcp_keepalive_probes = 5
net.ipv4.tcp_wmem = 8192 65536 16777216
net.ipv4.udp_wmem_min = 16384
net.ipv4.tcp_rmem = 8192 87380 16777216
net.ipv4.udp_rmem_min = 16384
#net.ipv4.tcp_mem = 65536 131072 262144
#net.ipv4.udp_mem = 65536 131072 262144
#net.ipv4.tcp_sack = 1
net.ipv4.tcp_congestion_control = htcp
net.ipv4.tcp_no_metrics_save = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_rfc1337 = 1
net.ipv4.ip_forward = 0
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.lo.rp_filter = 1
net.ipv4.conf.eth0.rp_filter = 1
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.lo.accept_source_route = 0
net.ipv4.conf.eth0.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0
net.core.netdev_max_backlog = 1000
net.core.optmem_max = 25165824
net.core.somaxconn = 20000
net.core.rmem_default=65536
net.core.wmem_default=65536
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
vm.swappiness = 10
net.ipv4.conf.icmp_echo_ignore_all = 1
EOF
sysctl -p

# Установка времени по мск
echo "Europe/Moscow" > /etc/timezone
dpkg-reconfigure -f noninteractive tzdata


# Установка Java 8
echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu precise main" > /etc/apt/sources.list.d/webupd8team-java.list
echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu precise main" >> /etc/apt/sources.list.d/webupd8team-java.list
apt-key adv --keyserver keyserver.ubuntu.com --recv-keys EEA14886
apt-get update
apt-get -y install oracle-java8-installer

# Защита от NTP Дудос атак
apt-get -y install ntp
echo '' >> /etc/ntp.conf
echo 'disable monitor' >> /etc/ntp.conf
service ntp restart
sed -i "2i exit 0" /etc/network/if-up.d/ntpdate

# Защита от Junk и прочего кала

sysctl -w net.netfilter.nf_conntrack_max=1200000
sysctl -w net.ipv4.tcp_max_orphans=512000

# Дропаем ошибочные пакеты и защита от SYN

iptables -t mangle -A PREROUTING -m conntrack --ctstate INVALID -j DROP
iptables -t mangle -A PREROUTING -p tcp ! --syn -m conntrack --ctstate NEW -j DROP

# Блокируем протоколы ESP, GRE, которые овх плохо фильтрует

iptables -A PREROUTING -p esp -j DROP -t raw
iptables -A PREROUTING -p gre -j DROP -t raw

# Ограничение количество максимальных подключений с одного айпи к портам

iptables -t raw -A PREROUTING -p tcp --dport 25565 -m connlimit --connlimit-above 2 -j DROP
iptables -t raw -A PREROUTING -p udp --dport 25565 -m connlimit --connlimit-above 2 -j DROP
iptables -t raw -A PREROUTING -p tcp --dport 80 -m connlimit --connlimit-above 2 -j DROP
iptables -t raw -A PREROUTING -p tcp --dport 443 -m connlimit --connlimit-above 2 -j DROP
iptables -t raw -A PREROUTING -p udp --dport 80 -m connlimit --connlimit-above 2 -j DROP
iptables -t raw -A PREROUTING -p udp --dport 443 -m connlimit --connlimit-above 2 -j DROP

# Закртие говно портов через них можно дудосить
iptables -A INPUT -p tcp --dport 25 -j DROP
iptables -A INPUT -p udp --dport 25 -j DROP
iptables -A INPUT -p tcp --dport 23 -j DROP
iptables -A INPUT -p udp --dport 23 -j DROP
iptables -A INPUT -p tcp --dport 43 -j DROP
iptables -A INPUT -p udp --dport 43 -j DROP
iptables -A INPUT -p tcp --dport 53 -j DROP
iptables -A INPUT -p udp --dport 53 -j DROP
iptables -A INPUT -p tcp --dport 68 -j DROP
iptables -A INPUT -p udp --dport 68 -j DROP
iptables -A INPUT -p tcp --dport 110 -j DROP
iptables -A INPUT -p udp --dport 110 -j DROP
iptables -A INPUT -p tcp --dport 115 -j DROP
iptables -A INPUT -p udp --dport 115 -j DROP
iptables -A INPUT -p tcp --dport 119 -j DROP
iptables -A INPUT -p udp --dport 119 -j DROP
iptables -A INPUT -p tcp --dport 123 -j DROP
iptables -A INPUT -p udp --dport 123 -j DROP
iptables -A INPUT -p tcp --dport 143 -j DROP
iptables -A INPUT -p udp --dport 143 -j DROP
iptables -A INPUT -p tcp --dport 161 -j DROP
iptables -A INPUT -p udp --dport 161 -j DROP
iptables -A INPUT -p tcp --dport 179 -j DROP
iptables -A INPUT -p udp --dport 179 -j DROP
iptables -A INPUT -p tcp --dport 220 -j DROP
iptables -A INPUT -p udp --dport 220 -j DROP
iptables -A INPUT -p tcp --dport 389 -j DROP
iptables -A INPUT -p udp --dport 389 -j DROP
iptables -A INPUT -p tcp --dport 993 -j DROP
iptables -A INPUT -p udp --dport 993 -j DROP
iptables -A INPUT -p tcp --dport 1723 -j DROP
iptables -A INPUT -p udp --dport 1723 -j DROP
iptables -A INPUT -p tcp --dport 2049 -j DROP
iptables -A INPUT -p udp --dport 2049 -j DROP
iptables -A INPUT -p tcp --dport 3389 -j DROP
iptables -A INPUT -p udp --dport 3389 -j DROP
iptables -A INPUT -p tcp --dport 5060 -j DROP
iptables -A INPUT -p udp --dport 5060 -j DROP
iptables -A INPUT -p tcp --dport 8080 -j DROP
iptables -A INPUT -p udp --dport 8080 -j DROP