> > iptables -A INPUT lo -p tcp --destination-port 10024 -j ACCEPT > > iptables -A OUTPUT -o lo -p tcp --destination-port 10024 -j ACCEPT > > iptables -A INPUT -i lo -p tcp --destination-port 10025 -j ACCEPT > > iptables -A OUTPUT -o lo -p tcp --destination-port 10025 -j ACCEPT > > You specified you want want to accept all lo traffic. Why add rules ? > > -- I changed some rules, some rules are removed and the position of the rules are changed. So i hope the script is more secure. I wan't to use an separate file to be included like an blacklist of trajan ports, but i'm very new with iptables (work since one week with it). How i have to build the rule do include an seperate file with near of 351 entries of ports wich are used by trojans? How i have to build the file (like "65536 #Adore Worm/Linux" ??) Thanx Peter But here my current script: #! /bin/sh modprobe ip_conntrack modprobe ip_conntrack_ftp modprobe ip_conntrack_irc modprobe ip_conntrack_pptp modprobe ip_conntrack_proto_gre modprobe ip_nat modprope ip_nat_pptp modprobe ip_nat_proto_gre # Flushen, Deleting, Create# ################################################################ iptables -F iptables -X iptables -t nat -F iptables -t nat -X iptables -t mangle -F iptables -t mangle -X iptables -N input_sperre iptables -N forward_sperre # Antworten zulassen # ###################### iptables -A sperre -m state --state ESTABLISHED,RELATED -j ACCEPT # first contact # ################# iptables -A sperre -i eth1 -s ! 192.168.1.0/255.255.255.0 -j DROP # Drop everything how not comes from lokal LAN iptables -A sperre -i eth1 --dport 22,19,21,22,25,3389,1723,23000:23001 -j ACCEPT # Allow outbound only for specific ports iptables -A sperre -i lo -s 127.0.0.1/255.0.0.0 -j ACCEPT # Allow everything from loopback iptables -A sperre -i eth0 -s 192.168.1.0/255.255.255.0 -j DROP # Drop everyting how comes fro outside to inside with LAN IP's # acceptstuff # ############### iptables -A sperre -p tcp --dport 21 -j ACCEPT # ftp iptables -A sperre -p tcp --dport 23000:23001 -j ACCEPT # Battlefield Server iptables -A sperre -p tcp --dport 90 -j ACCEPT # DVISE iptables -A sperre -p tcp --dport 80 -j ACCEPT # HTTP iptables -A sperre -p tcp --dport 3389 -j ACCEPT # VPN # Reject everything else (RFC-conform) # ####################################### iptables -A sperre -p tcp -j REJECT --reject-with tcp-reset iptables -A sperre -p udp -j REJECT --reject-with icmp-port-unreachable # activating sperre# ##################### iptables -A INPUT -j input_sperre iptables -A FORWARD -j forward_sperre iptables -P INPUT DROP iptables -P FORWARD DROP iptables -P OUTPUT ACCEPT # output accept iptables -P OUTPUT ACCEPT -t nat # NAT # ####### iptables -A POSTROUTING -t nat -o eth0 -j MASQUERADE iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 21 -j DNAT --to 192.168.1.198 # FTP to FTP-Server iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 1723 -j DNAT --to 192.168.1.2 # VPN Server iptables -A PREROUTING -t nat -i eth0 -p 47 -j DNAT --to 192.168.1.2 # VPN Server iptables -A PREROUTING -t nat -i eth0 -p 37 -j DNAT --to 192.168.1.2 # VPN Server iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 4661:4662 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 6343 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 6300 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 4242 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 8888 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 6661:6662 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p udp --dport 4665 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p udp --dport 4672 -j DNAT --to 192.168.1.198 # EDONKEY iptables -A PREROUTING -t nat -i eth0 -p udp --dport 6665 -j DNAT --to 192.168.1.198 # EDONKEY # Special Rules iptables -A INPUT -i eth0 -s 0/0 -p tcp --destination-port 25 -j ACCEPT iptables -A OUTPUT -o eth1 -s 0/0 -p tcp --destination-port 25 -j ACCEPT iptables -A INPUT -i eth0 -s 192.168.1.0/24 -p tcp --destination-port 25 -j ACCEPT iptables -A OUTPUT -o eth0 -s 0/0 -p tcp --destination-port 25 -j ACCEPT iptables -A INPUT lo -p tcp --destination-port 10024 -j ACCEPT iptables -A OUTPUT -o lo -p tcp --destination-port 10024 -j ACCEPT iptables -A INPUT -i lo -p tcp --destination-port 10025 -j ACCEPT iptables -A OUTPUT -o lo -p tcp --destination-port 10025 -j ACCEPT echo "1" > /proc/sys/net/ipv4/ip_forward # Initialising of Forwarding echo "Firewall started" To: blancher@xxxxxxxxxxxxxxxxxx Cc: netfilter@xxxxxxxxxxxxxxxxxxx
