stockholm/modules/iptables.nix
2015-05-19 23:10:57 +02:00

70 lines
2.3 KiB
Nix

{ config, pkgs, ... }:
{
#
# iptables
#
networking.firewall.enable = false;
system.activationScripts.iptables =
let
log = false;
when = c: f: if c then f else "";
in
''
ip4tables() { ${pkgs.iptables}/sbin/iptables "$@"; }
ip6tables() { ${pkgs.iptables}/sbin/ip6tables "$@"; }
ipXtables() { ip4tables "$@"; ip6tables "$@"; }
#
# nat
#
# reset tables
ipXtables -t nat -F
ipXtables -t nat -X
#
ipXtables -t nat -A PREROUTING -j REDIRECT ! -i retiolum -p tcp --dport ssh --to-ports 0
ipXtables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 11423 --to-ports ssh
#
# filter
#
# reset tables
ipXtables -P INPUT DROP
ipXtables -P FORWARD DROP
ipXtables -F
ipXtables -X
# create custom chains
ipXtables -N Retiolum
# INPUT
ipXtables -A INPUT -j ACCEPT -m conntrack --ctstate RELATED,ESTABLISHED
ipXtables -A INPUT -j ACCEPT -i lo
ipXtables -A INPUT -j ACCEPT -p tcp --dport ssh -m conntrack --ctstate NEW
ipXtables -A INPUT -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
ipXtables -A INPUT -j ACCEPT -p tcp --dport tinc -m conntrack --ctstate NEW
ipXtables -A INPUT -j ACCEPT -p tcp --dport smtp -m conntrack --ctstate NEW
ipXtables -A INPUT -j Retiolum -i retiolum
${when log "ipXtables -A INPUT -j LOG --log-level info --log-prefix 'INPUT DROP '"}
# FORWARD
${when log "ipXtables -A FORWARD -j LOG --log-level info --log-prefix 'FORWARD DROP '"}
# Retiolum
ip4tables -A Retiolum -j ACCEPT -p icmp --icmp-type echo-request
ip6tables -A Retiolum -j ACCEPT -p ipv6-icmp -m icmp6 --icmpv6-type echo-request
${when log "ipXtables -A Retiolum -j LOG --log-level info --log-prefix 'REJECT '"}
ipXtables -A Retiolum -j REJECT -p tcp --reject-with tcp-reset
ip4tables -A Retiolum -j REJECT -p udp --reject-with icmp-port-unreachable
ip4tables -A Retiolum -j REJECT --reject-with icmp-proto-unreachable
ip6tables -A Retiolum -j REJECT -p udp --reject-with icmp6-port-unreachable
ip6tables -A Retiolum -j REJECT
'';
}