Depois que troquei minhas regras de firewall, minha net funciona meio intermitente mas os serviços iptables e squid não caem. O que pode ser? Abaixo estão as regras.
"
# Script de Firewall e Roteamento de Portas
#
# Ativa Modulos
modprobe iptable_nat
modprobe ip_conntrack
modprobe ip_conntrack_ftp
modprobe ip_nat_ftp
modprobe ipt_LOG
modprobe ipt_REJECT
modprobe ipt_MASQUERADE
#
# Ativa roteamento no kernel
echo "1" > /proc/sys/net/ipv4/ip_forward
#
# Protecao contra IP spoofing
echo "1" > /proc/sys/net/ipv4/conf/all/rp_filter
#
# Zera regras
iptables -F
iptables -X
iptables -F -t nat
iptables -X -t nat
iptables -F -t mangle
iptables -X -t mangle
#
# Determina a politica padrao
iptables -P INPUT DROP
iptables -P OUTPUT DROP
iptables -P FORWARD DROP
#
# Aceita os pacotes que realmente devem entrar
iptables -A INPUT -i ! eth0 -j ACCEPT
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -m state --state ESTABLISHED,RELATED,NEW -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED,NEW -j ACCEPT
#
# Protecao contra trinoo
iptables -N TRINOO
iptables -A TRINOO -m limit --limit 15/m -j LOG --log-level 6 --log-prefix "FIREWALL: trinoo: "
iptables -A TRINOO -j DROP
iptables -A INPUT -p TCP -i eth0 --dport 27444 -j TRINOO
iptables -A INPUT -p TCP -i eth0 --dport 27665 -j TRINOO
iptables -A INPUT -p TCP -i eth0 --dport 31335 -j TRINOO
iptables -A INPUT -p TCP -i eth0 --dport 34555 -j TRINOO
iptables -A INPUT -p TCP -i eth0 --dport 35555 -j TRINOO
#
# Protecao contra trojans
iptables -N TROJAN
iptables -A TROJAN -m limit --limit 15/m -j LOG --log-level 6 --log-prefix "FIREWALL: trojan: "
iptables -A TROJAN -j DROP
iptables -A INPUT -p TCP -i eth0 --dport 666 -j TROJAN
iptables -A INPUT -p TCP -i eth0 --dport 666 -j TROJAN
iptables -A INPUT -p TCP -i eth0 --dport 4000 -j TROJAN
iptables -A INPUT -p TCP -i eth0 --dport 6000 -j TROJAN
iptables -A INPUT -p TCP -i eth0 --dport 6006 -j TROJAN
iptables -A INPUT -p TCP -i eth0 --dport 16660 -j TROJAN
#
# Protecao contra worms
iptables -A FORWARD -p tcp --dport 135 -i eth1 -j REJECT
#
# Protecao contra syn-flood
iptables -A FORWARD -p tcp --syn -m limit --limit 2/s -j ACCEPT
#
# Protecao contra ping da morte
iptables -A FORWARD -p icmp --icmp-type echo-request -m limit --limit 1/s -j ACCEPT
#
# Protecao contra port scanners
iptables -N SCANNER
iptables -A SCANNER -m limit --limit 15/m -j LOG --log-level 6 --log-prefix "FIREWALL: port scanner: "
iptables -A SCANNER -j DROP
iptables -A INPUT -p tcp --tcp-flags ALL FIN,URG,PSH -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags ALL NONE -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags ALL ALL -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags ALL FIN,SYN -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags SYN,RST SYN,RST -i eth0 -j SCANNER
iptables -A INPUT -p tcp --tcp-flags SYN,FIN SYN,FIN -i eth0 -j SCANNER
#
#Habilita (NAT) Para converter ip 192.168.1.x para 200.x.x.x
#iptables -t nat -A POSTROUTING -s 192.168.172.0/24 -o eth1 -j SNAT --to 192.168.172.17
#iptables -t nat -A POSTROUTING -s 192.168.172.0/24 -o eth0 -j MASQUERADE
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
#
#Redireciona Todas as portas para a 8080 (http) (Squid)
iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 80 -j REDIRECT --to 8080
#
#-------------------- CONTROLA TODAS AS INPUT NO SERVIDOR ---------------------
#
#Libera as portas para entrada no servidor
#
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 53 -j ACCEPT
iptables -A INPUT -p udp -s 192.168.172.0/24 --dport 53 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 8080 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 80 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 25 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 110 -j ACCEPT
iptables -A INPUT -p tcp -s 192.168.172.0/24 --dport 137:139 -j ACCEPT
iptables -A INPUT -p udp -s 192.168.172.0/24 --dport 137:139 -j ACCEPT
#Mantem a conexao das portas liberada acima
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
#--------------------- CONTROLA TODOS OS FORWARD NO SERVIDOR ------------------
#
#libera as portas para passar pelo servidor e ter acesso externo
iptables -A FORWARD -s 192.168.172.0/24 -i eth1 -j ACCEPT
iptables -A FORWARD -p tcp -s 192.168.172.0/24 --dport 25 -j ACCEPT
iptables -A FORWARD -p tcp -s 192.168.172.0/24 --dport 110 -j ACCEPT
iptables -A FORWARD -p tcp -s 192.168.172.0/24 --dport 80 -j ACCEPT
#Mantem a conexao das portas acima liberada
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
#Portas Bloqueadas (MSN)
iptables -A FORWARD -p TCP --dport 1863 -j DROP
iptables -A FORWARD -d 64.4.13.0/24 -j REJECT
"
