Ett annat tips är att använda denna scriptgenerator;
http://easyfwgen.morizot.net/gen/
Den frågar om ditt nätverk och skapar iptblesregler utifrån dina svar. För ditt nätverk sklle det kunna se ut såhär;
[quote]#!/bin/sh
#
# Generated iptables firewall script for the Linux 2.4 kernel
# Script generated by Easy Firewall Generator for IPTables 1.15
# copyright 2002 Timothy Scott Morizot
#
# Redhat chkconfig comments - firewall applied early,
# removed late
# chkconfig: 2345 08 92
# description: This script applies or removes iptables firewall rules
#
# This generator is primarily designed for RedHat installations,
# although it should be adaptable for others.
#
# It can be executed with the typical start and stop arguments.
# If used with stop, it will stop after flushing the firewall.
# The save and restore arguments will save or restore the rules
# from the /etc/sysconfig/iptables file. The save and restore
# arguments are included to preserve compatibility with
# Redhat's or Fedora's init.d script if you prefer to use it.
# Redhat/Fedora installation instructions
#
# 1. Have the system link the iptables init.d startup script into run states
# 2, 3, and 5.
# chkconfig --level 235 iptables on
#
# 2. Save this script and execute it to load the ruleset from this file.
# You may need to run the dos2unix command on it to remove carraige returns.
#
# 3. To have it applied at startup, copy this script to
# /etc/init.d/iptables. It accepts stop, start, save, and restore
# arguments. (You may wish to save the existing one first.)
# Alternatively, if you issue the 'service iptables save' command
# the init.d script should save the rules and reload them at runtime.
#
# 4. For non-Redhat systems (or Redhat systems if you have a problem), you
# may want to append the command to execute this script to rc.local.
# rc.local is typically located in /etc and /etc/rc.d and is usually
# the last thing executed on startup. Simply add /path/to/script/script_name
# on its own line in the rc.local file.
###############################################################################
#
# Local Settings
#
# sysctl location. If set, it will use sysctl to adjust the kernel parameters.
# If this is set to the empty string (or is unset), the use of sysctl
# is disabled.
SYSCTL="/sbin/sysctl -w"
# To echo the value directly to the /proc file instead
# SYSCTL=""
# IPTables Location - adjust if needed
IPT="/sbin/iptables"
IPTS="/sbin/iptables-save"
IPTR="/sbin/iptables-restore"
# Internet Interface
INET_IFACE="ppp0"
# Local Interface Information
LOCAL_IFACE="eth0"
LOCAL_IP="192.168.0.1"
LOCAL_NET="192.168.1.0/24"
LOCAL_BCAST="192.168.1.255"
# Localhost Interface
LO_IFACE="lo"
LO_IP="127.0.0.1"
# Save and Restore arguments handled here
if [ "$1" = "save" ]
then
echo -n "Saving firewall to /etc/sysconfig/iptables ... "
$IPTS > /etc/sysconfig/iptables
echo "done"
exit 0
elif [ "$1" = "restore" ]
then
echo -n "Restoring firewall from /etc/sysconfig/iptables ... "
$IPTR < /etc/sysconfig/iptables
echo "done"
exit 0
fi
###############################################################################
#
# Load Modules
#
echo "Loading kernel modules ..."
# You should uncomment the line below and run it the first time just to
# ensure all kernel module dependencies are OK. There is no need to run
# every time, however.
# /sbin/depmod -a
# Unless you have kernel module auto-loading disabled, you should not
# need to manually load each of these modules. Other than ip_tables,
# ip_conntrack, and some of the optional modules, I've left these
# commented by default. Uncomment if you have any problems or if
# you have disabled module autoload. Note that some modules must
# be loaded by another kernel module.
# core netfilter module
/sbin/modprobe ip_tables
# the stateful connection tracking module
/sbin/modprobe ip_conntrack
# filter table module
# /sbin/modprobe iptable_filter
# mangle table module
# /sbin/modprobe iptable_mangle
# nat table module
# /sbin/modprobe iptable_nat
# LOG target module
# /sbin/modprobe ipt_LOG
# This is used to limit the number of packets per sec/min/hr
# /sbin/modprobe ipt_limit
# masquerade target module
# /sbin/modprobe ipt_MASQUERADE
# filter using owner as part of the match
# /sbin/modprobe ipt_owner
# REJECT target drops the packet and returns an ICMP response.
# The response is configurable. By default, connection refused.
# /sbin/modprobe ipt_REJECT
# This target allows packets to be marked in the mangle table
# /sbin/modprobe ipt_mark
# This target affects the TCP MSS
# /sbin/modprobe ipt_tcpmss
# This match allows multiple ports instead of a single port or range
# /sbin/modprobe multiport
# This match checks against the TCP flags
# /sbin/modprobe ipt_state
# This match catches packets with invalid flags
# /sbin/modprobe ipt_unclean
# The ftp nat module is required for non-PASV ftp support
/sbin/modprobe ip_nat_ftp
# the module for full ftp connection tracking
/sbin/modprobe ip_conntrack_ftp
# the module for full irc connection tracking
/sbin/modprobe ip_conntrack_irc
###############################################################################
#
# Kernel Parameter Configuration
#
# See
http://ipsysctl-tutorial.frozentux.net/ ... index.html
# for a detailed tutorial on sysctl and the various settings
# available.
# Required to enable IPv4 forwarding.
# Redhat users can try setting FORWARD_IPV4 in /etc/sysconfig/network to true
# Alternatively, it can be set in /etc/sysctl.conf
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/ip_forward
else
$SYSCTL net.ipv4.ip_forward="1"
fi
# This enables dynamic address hacking.
# This may help if you have a dynamic IP address \(e.g. slip, ppp, dhcp\).
#if [ "$SYSCTL" = "" ]
#then
# echo "1" > /proc/sys/net/ipv4/ip_dynaddr
#else
# $SYSCTL net.ipv4.ip_dynaddr="1"
#fi
# This enables SYN flood protection.
# The SYN cookies activation allows your system to accept an unlimited
# number of TCP connections while still trying to give reasonable
# service during a denial of service attack.
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/tcp_syncookies
else
$SYSCTL net.ipv4.tcp_syncookies="1"
fi
# This enables source validation by reversed path according to RFC1812.
# In other words, did the response packet originate from the same interface
# through which the source packet was sent? It's recommended for single-homed
# systems and routers on stub networks. Since those are the configurations
# this firewall is designed to support, I turn it on by default.
# Turn it off if you use multiple NICs connected to the same network.
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/conf/all/rp_filter
else
$SYSCTL net.ipv4.conf.all.rp_filter="1"
fi
# This option allows a subnet to be firewalled with a single IP address.
# It's used to build a DMZ. Since that's not a focus of this firewall
# script, it's not enabled by default, but is included for reference.
# See:
http://www.sjdjweis.com/linux/proxyarp/
#if [ "$SYSCTL" = "" ]
#then
# echo "1" > /proc/sys/net/ipv4/conf/all/proxy_arp
#else
# $SYSCTL net.ipv4.conf.all.proxy_arp="1"
#fi
# The following kernel settings were suggested by Alex Weeks. Thanks!
# This kernel parameter instructs the kernel to ignore all ICMP
# echo requests sent to the broadcast address. This prevents
# a number of smurfs and similar DoS nasty attacks.
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
else
$SYSCTL net.ipv4.icmp_echo_ignore_broadcasts="1"
fi
# This option can be used to accept or refuse source routed
# packets. It is usually on by default, but is generally
# considered a security risk. This option turns it off.
if [ "$SYSCTL" = "" ]
then
echo "0" > /proc/sys/net/ipv4/conf/all/accept_source_route
else
$SYSCTL net.ipv4.conf.all.accept_source_route="0"
fi
# This option can disable ICMP redirects. ICMP redirects
# are generally considered a security risk and shouldn't be
# needed by most systems using this generator.
#if [ "$SYSCTL" = "" ]
#then
# echo "0" > /proc/sys/net/ipv4/conf/all/accept_redirects
#else
# $SYSCTL net.ipv4.conf.all.accept_redirects="0"
#fi
# However, we'll ensure the secure_redirects option is on instead.
# This option accepts only from gateways in the default gateways list.
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/conf/all/secure_redirects
else
$SYSCTL net.ipv4.conf.all.secure_redirects="1"
fi
# This option logs packets from impossible addresses.
if [ "$SYSCTL" = "" ]
then
echo "1" > /proc/sys/net/ipv4/conf/all/log_martians
else
$SYSCTL net.ipv4.conf.all.log_martians="1"
fi
###############################################################################
#
# Flush Any Existing Rules or Chains
#
echo "Flushing Tables ..."
# Reset Default Policies
$IPT -P INPUT ACCEPT
$IPT -P FORWARD ACCEPT
$IPT -P OUTPUT ACCEPT
$IPT -t nat -P PREROUTING ACCEPT
$IPT -t nat -P POSTROUTING ACCEPT
$IPT -t nat -P OUTPUT ACCEPT
$IPT -t mangle -P PREROUTING ACCEPT
$IPT -t mangle -P OUTPUT ACCEPT
# Flush all rules
$IPT -F
$IPT -t nat -F
$IPT -t mangle -F
# Erase all non-default chains
$IPT -X
$IPT -t nat -X
$IPT -t mangle -X
if [ "$1" = "stop" ]
then
echo "Firewall completely flushed! Now running with no firewall."
exit 0
fi
###############################################################################
#
# Rules Configuration
#
###############################################################################
#
# Filter Table
#
###############################################################################
# Set Policies
$IPT -P INPUT DROP
$IPT -P OUTPUT DROP
$IPT -P FORWARD DROP
###############################################################################
#
# User-Specified Chains
#
# Create user chains to reduce the number of rules each packet
# must traverse.
echo "Create and populate custom rule chains ..."
# Create a chain to filter INVALID packets
$IPT -N bad_packets
# Create another chain to filter bad tcp packets
$IPT -N bad_tcp_packets
# Create separate chains for icmp, tcp (incoming and outgoing),
# and incoming udp packets.
$IPT -N icmp_packets
# Used for UDP packets inbound from the Internet
$IPT -N udp_inbound
# Used to block outbound UDP services from internal network
# Default to allow all
$IPT -N udp_outbound
# Used to allow inbound services if desired
# Default fail except for established sessions
$IPT -N tcp_inbound
# Used to block outbound services from internal network
# Default to allow all
$IPT -N tcp_outbound
###############################################################################
#
# Populate User Chains
#
# bad_packets chain
#
# Drop packets received on the external interface
# claiming a source of the local network
$IPT -A bad_packets -p ALL -i $INET_IFACE -s $LOCAL_NET -j LOG \
--log-prefix "Illegal source: "
$IPT -A bad_packets -p ALL -i $INET_IFACE -s $LOCAL_NET -j DROP
# Drop INVALID packets immediately
$IPT -A bad_packets -p ALL -m state --state INVALID -j LOG \
--log-prefix "Invalid packet: "
$IPT -A bad_packets -p ALL -m state --state INVALID -j DROP
# Then check the tcp packets for additional problems
$IPT -A bad_packets -p tcp -j bad_tcp_packets
# All good, so return
$IPT -A bad_packets -p ALL -j RETURN
# bad_tcp_packets chain
#
# All tcp packets will traverse this chain.
# Every new connection attempt should begin with
# a syn packet. If it doesn't, it is likely a
# port scan. This drops packets in state
# NEW that are not flagged as syn packets.
# Return to the calling chain if the bad packets originate
# from the local interface. This maintains the approach
# throughout this firewall of a largely trusted internal
# network.
$IPT -A bad_tcp_packets -p tcp -i $LOCAL_IFACE -j RETURN
# However, I originally did apply this filter to the forward chain
# for packets originating from the internal network. While I have
# not conclusively determined its effect, it appears to have the
# interesting side effect of blocking some of the ad systems.
# Apparently some ad systems have the browser initiate a NEW
# connection that is not flagged as a syn packet to retrieve
# the ad image. If you wish to experiment further comment the
# rule above. If you try it, you may also wish to uncomment the
# rule below. It will keep those packets from being logged.
# There are a lot of them.
# $IPT -A bad_tcp_packets -p tcp -i $LOCAL_IFACE ! --syn -m state \
# --state NEW -j DROP
$IPT -A bad_tcp_packets -p tcp ! --syn -m state --state NEW -j LOG \
--log-prefix "New not syn: "
$IPT -A bad_tcp_packets -p tcp ! --syn -m state --state NEW -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL NONE -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL NONE -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL ALL -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL ALL -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL FIN,URG,PSH -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL FIN,URG,PSH -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags SYN,RST SYN,RST -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags SYN,RST SYN,RST -j DROP
$IPT -A bad_tcp_packets -p tcp --tcp-flags SYN,FIN SYN,FIN -j LOG \
--log-prefix "Stealth scan: "
$IPT -A bad_tcp_packets -p tcp --tcp-flags SYN,FIN SYN,FIN -j DROP
# All good, so return
$IPT -A bad_tcp_packets -p tcp -j RETURN
# icmp_packets chain
#
# This chain is for inbound (from the Internet) icmp packets only.
# Type 8 (Echo Request) is not accepted by default
# Enable it if you want remote hosts to be able to reach you.
# 11 (Time Exceeded) is the only one accepted
# that would not already be covered by the established
# connection rule. Applied to INPUT on the external interface.
#
# See:
http://www.ee.siue.edu/~rwalden/networking/icmp.html
# for more info on ICMP types.
#
# Note that the stateful settings allow replies to ICMP packets.
# These rules allow new packets of the specified types.
# ICMP packets should fit in a Layer 2 frame, thus they should
# never be fragmented. Fragmented ICMP packets are a typical sign
# of a denial of service attack.
$IPT -A icmp_packets --fragment -p ICMP -j LOG \
--log-prefix "ICMP Fragment: "
$IPT -A icmp_packets --fragment -p ICMP -j DROP
# Echo - uncomment to allow your system to be pinged.
# Uncomment the LOG command if you also want to log PING attempts
#
# $IPT -A icmp_packets -p ICMP -s 0/0 --icmp-type 8 -j LOG \
# --log-prefix "Ping detected: "
# $IPT -A icmp_packets -p ICMP -s 0/0 --icmp-type 8 -j ACCEPT
# By default, however, drop pings without logging. Blaster
# and other worms have infected systems blasting pings.
# Comment the line below if you want pings logged, but it
# will likely fill your logs.
$IPT -A icmp_packets -p ICMP -s 0/0 --icmp-type 8 -j DROP
# Time Exceeded
$IPT -A icmp_packets -p ICMP -s 0/0 --icmp-type 11 -j ACCEPT
# Not matched, so return so it will be logged
$IPT -A icmp_packets -p ICMP -j RETURN
# TCP & UDP
# Identify ports at:
#
http://www.chebucto.ns.ca/~rakerman/port-table.html
#
http://www.iana.org/assignments/port-numbers
# udp_inbound chain
#
# This chain describes the inbound UDP packets it will accept.
# It's applied to INPUT on the external or Internet interface.
# Note that the stateful settings allow replies.
# These rules are for new requests.
# It drops netbios packets (windows) immediately without logging.
# Drop netbios calls
# Please note that these rules do not really change the way the firewall
# treats netbios connections. Connections from the localhost and
# internal interface (if one exists) are accepted by default.
# Responses from the Internet to requests initiated by or through
# the firewall are also accepted by default. To get here, the
# packets would have to be part of a new request received by the
# Internet interface. You would have to manually add rules to
# accept these. I added these rules because some network connections,
# such as those via cable modems, tend to be filled with noise from
# unprotected Windows machines. These rules drop those packets
# quickly and without logging them. This prevents them from traversing
# the whole chain and keeps the log from getting cluttered with
# chatter from Windows systems.
$IPT -A udp_inbound -p UDP -s 0/0 --destination-port 137 -j DROP
$IPT -A udp_inbound -p UDP -s 0/0 --destination-port 138 -j DROP
# Ident requests (Port 113) must have a REJECT rule rather than the
# default DROP rule. This is the minimum requirement to avoid
# long delays while connecting. Also see the tcp_inbound rule.
$IPT -A udp_inbound -p UDP -s 0/0 --destination-port 113 -j REJECT
# A more sophisticated configuration could accept the ident requests.
# $IPT -A udp_inbound -p UDP -s 0/0 --destination-port 113 -j ACCEPT
# However, if this is a gateway system that masquerades/nats for internal systems
# and the internal systems wish to chat, a simple changing these rules to
# ACCEPT won't work. The ident daemon on the gateway will need to know how
# to handle the requests. The stock daemon in most linux distributions
# can't do that. oidentd is one package that can.
# See:
http://dev.ojnk.net/[/qoute]
---klippt forts;
Xubuntu på flera maskiner. Men inte Unity!
Mer Terminalanvändande i Ubuntu vore bra. Och Xfce. Och Mate.
Jag har installerat om Ubuntu och nu får jag inte delningen av Internet att fungerar med min Xbox 360
Fungerade inte det heller