[suse 8.0] server ping

[Verwijderd]

ik kom er nog niet uit.

Vanachter mijn firewall kan ik mijn server niet eens pingen met ipadres. Wel met intern ip, maar niet met extern ip. Ik kan dus ook niet services benaderen die op mijn server draaien. dwz, niet met mijn url of externe ip dus. Dat maakt sommige dingen erg moeilijk. En het zou moeten kunnen. Met suse 6 weas het in elk geval geen probleem. SuSE-ondersteuning wil geen antwoord geven (valt buiten de scope etc). Verder werkt internet vanachter (of vanaf) de firewall prima.

Het moet iets met de firewall te maken hebben die op mijn suse machine draait. Verder werkt alles goed, en volgens de verwachtingen nav de settings. Als firewall gebruik ik het standaard script dat bij suse zit. Iptables dus. Heb ik nog totaal geen ervaring mee.

Heeft iemand suggesties wat ik zou kunnen proberen?

[RvdH]

Het iptables script hier posten?

[Verwijderd]

hmmm dat werkt met een instel script. Ik wil hier wel poten, maar vind je goed als ik alle tekst eruit strip? anders wordt het wel een hele lap, Met daarin maar een paar variabelen instellingen

Wat vind je hiervan?
Dit is de foutmelding die ik krijg in mijn firewall log.

May 13 21:09:25 linux kernel: SuSE-FW-NO_ACCESS_INT->FWEXT IN=eth2 OUT= MAC=00:50:bf:d5:71:61:00:50:bf:d6:b0:ca:08:00 SRC=192.168.1.05 DST=62.238.44.4 LEN=60 TOS=0x08 PREC=0x00 TTL=64 ID=47294 DF PROTO=TCP SPT=33678 DPT=80 WINDOW=5840 RES=0x00 SYN URGP=0 OPT (020405B40402080A00114C850000000001030300)

eth2 dat is mijn interne netwerk.

De services zijn voor anderen wel bereikbaar en intern voor mij ook. Alleen maar niet zo dus. Van achter de firewall met het externe ip.

[RvdH]

Die error betekent dat je packets die geforward worden van eth2 naar je ext interface geblocked worden. Dus dat zul je of in de SuSE instellingen moeten veranderen, of handmatig een regel toevoegen die dat wel toelaat.

Het zal in het firewall script staan bij de rules voor de chain FWEXT.

[Verwijderd]

ik heb net iets geprobeerd.

Firewall in testmode. Dan laattie alles door, maar geeft een logmelding voor alles wat anders geblocked zou zijn.

Dit zijn de meldingen die ik krijg:

UDP: short packet: 556/548

Ik ben me al rot aan het zoeken wat short packets zijn, maar niets dan vage aanwijzingen. Kennelijk worden die gefilterd....

Enig idee?

[RvdH]

Niet zo heel erg interessant.. zijn waarschijnlijk upnp broadcasts van een WinXP machine als je die hebt.

Post dat iptables script nou eens, want zo schiet niemand er wat mee op

[Verwijderd]

Kommtieeeeee...



# External network

FW_DEV_EXT="eth0"


# Which is the interface that points to the internal network?

FW_DEV_INT="eth1 eth2"


# Which is the interface that points to the dmz or dialup network?

FW_DEV_DMZ=""


# Should routing between the internet, dmz and internal network be activated?
# REQUIRES: FW_DEV_INT or FW_DEV_DMZ
#
# You need only set this to yes, if you either want to masquerade internal
# machines

FW_ROUTE="yes"

#
# 6.)
# Do you want to masquerade internal networks to the outside?
# REQUIRES: FW_DEV_INT or FW_DEV_DMZ, FW_ROUTE

FW_MASQUERADE="yes"
#
# You must also define on which interface(s) to masquerade on. This is
# normally your external device(s) to the internet.
# Most users can leave the default below.
#
# e.g. "ippp0" or "$FW_DEV_EXT"
FW_MASQ_DEV="$FW_DEV_EXT"


# Which internal computers/networks are allowed to access the internet
# directly (not via proxys on the firewall)?
# Only these networks will be allowed access and will be masqueraded!
#
# Choice: leave empty or any number of hosts/networks seperated by a space.
# Every host/network may get a list of allowed services, otherwise everything
# is allowed. A target network, protocol and service is appended by a comma to
# the host/network. e.g. "10.0.0.0/8" allows the whole 10.0.0.0 network with
# unrestricted access. "10.0.1.0/24,0/0,tcp,80 10.0.1.0/24,0/0tcp,21" allows
# the 10.0.1.0 network to use www/ftp to the internet.
# "10.0.1.0/24,tcp,1024:65535 10.0.2.0/24" is OK too.
# Set this variable to "0/0" to allow unrestricted access to the internet.
#
FW_MASQ_NETS="192.168.0.0/16,0/0"

#
# 7.)
# Do you want to protect the firewall from the internal network?
# REQUIRES: FW_DEV_INT
#
# If you set this to "yes", internal machines may only access services on
# the machine you explicitly allow. They will be also affected from the
# FW_AUTOPROTECT_SERVICES option.
# If you set this to "no", any user can connect (and attack) any service on
# the firewall.
#
# Choice: "yes" or "no", defaults to "yes"
#
# "yes" is a good choice
FW_PROTECT_FROM_INTERNAL="no"

#
# 8.)
# Do you want to autoprotect all running network services on the firewall?
#
# If set to "yes", all network access to services TCP and UDP on this machine
# will be prevented (except to those which you explicitly allow, see below:
# FW_SERVICES_{EXT,DMZ,INT}_{TCP,UDP})
#
# Choice: "yes" or "no", defaults to "yes"
#
FW_AUTOPROTECT_SERVICES="yes"

#
# 9.)
# Which services ON THE FIREWALL should be accessible from either the internet
# (or other untrusted networks), the dmz or internal (trusted networks)?
# (see no.13 & 14 if you want to route traffic through the firewall) XXX
#
# Enter all ports or known portnames below, seperated by a space.
# TCP services (e.g. SMTP, WWW) must be set in FW_SERVICES_*_TCP, and
# UDP services (e.g. syslog) must be set in FW_SERVICES_*_UDP.
# e.g. if a webserver on the firewall should be accessible from the internet:
# FW_SERVICES_EXT_TCP="www"
# e.g. if the firewall should receive syslog messages from the dmz:
# FW_SERVICES_DMZ_UDP="syslog"
# For IP protocols (like GRE for PPTP, or OSPF for routing) you need to set
# FW_SERVICES_*_IP with the protocol name or number (see /etc/protocols)
#
# Choice: leave empty or any number of ports, known portnames (from
# /etc/services) and port ranges seperated by a space. Port ranges are
# written like this: allow port 1 to 10 -> "1:10"
# e.g. "", "smtp", "123 514", "3200:3299", "ftp 22 telnet 512:514"
# For FW_SERVICES_*_IP enter the protocol name (like "igmp") or number ("2")
#
# Common: smtp domain
FW_SERVICES_EXT_TCP="80 ftp 23"
# Common: domain
FW_SERVICES_EXT_UDP=""
# Common: domain
# For VPN/Routing which END at the firewall!!
FW_SERVICES_EXT_IP=""
#
# Common: smtp domain
FW_SERVICES_DMZ_TCP=""
# Common: domain
FW_SERVICES_DMZ_UDP=""
# For VPN/Routing which END at the firewall!!
FW_SERVICES_DMZ_IP=""
#
# Common: ssh smtp domain
FW_SERVICES_INT_TCP="1:65535"
# Common: domain syslog
FW_SERVICES_INT_UDP="1:65535"
# For VPN/Routing which END at the firewall!!
FW_SERVICES_INT_IP=""

#
# 10.)
# Which services should be accessible from trusted hosts/nets?
#
# Define trusted hosts/networks (doesnt matter if they are internal or
# external) and the TCP and/or UDP services they are allowed to use.
# Please note that a trusted host/net is *not* allowed to ping the firewall
# until you set it to allow also icmp!
#
# Choice: leave FW_TRUSTED_NETS empty or any number of computers and/or
# networks, seperated by a space. e.g. "172.20.1.1 172.20.0.0/16"
# Optional, enter a protocol after a comma, e.g. "1.1.1.1,icmp"
# Optional, enter a port after a protocol, e.g. "2.2.2.2,tcp,22"
#
FW_TRUSTED_NETS="192.168.0.0/16"

#
# 11.)
# How is access allowed to high (unpriviliged [above 1023]) ports?
#
# You may either allow everyone from anyport access to your highports ("yes"),
# disallow anyone ("no"), anyone who comes from a defined port (portnumber or
# known portname) [note that this is easy to circumvent!], or just your
# defined nameservers ("DNS").
# Note that you can't use rpc requests (e.g. rpcinfo, showmount) as root
# from a firewall using this script (well, you can if you include range
# 600:1023 in FW_SERVICES_EXT_UDP ...).
# Please note that with v2.1 "yes" is not mandatory for active FTP from
# the firewall anymore.
#
# Choice: "yes", "no", "DNS", portnumber or known portname, defaults to "no"
# if not set
#
# Common: "ftp-data", better is "yes" to be sure that everything else works
FW_ALLOW_INCOMING_HIGHPORTS_TCP="yes"
# Common: "DNS" or "domain ntp", better is "yes" to be sure ...
FW_ALLOW_INCOMING_HIGHPORTS_UDP="no"

#
# 12.)
# Are you running some of the services below?
# They need special attention - otherwise they wonŽt work!
#
# Set services you are running to "yes", all others to "no", defaults to "no"
# if not set.
#
FW_SERVICE_AUTODETECT="yes"
# Autodetect the services below when starting
#
# If you are running bind/named set to yes. Remember that you have to open
# port 53 (or "domain") as udp/tcp to allow incoming queries.
# Also FW_ALLOW_INCOMING_HIGHPORTS_UDP needs to be "yes"
FW_SERVICE_DNS="no"
#
# if you use dhclient to get an ip address you have to set this to "yes" !
FW_SERVICE_DHCLIENT="yes"
#
# set to "yes" if this server is a DHCP server
FW_SERVICE_DHCPD="no"
#
# set to "yes" if this server is running squid. You still have to open the
# tcp port 3128 to allow remote access to the squid proxy service.
FW_SERVICE_SQUID="no"
#
# set to "yes" if this server is running a samba server. You still have to open
# the tcp port 139 to allow remote access to SAMBA.
FW_SERVICE_SAMBA="yes"

#
# 13.)
# Which services accessed from the internet should be allowed to the
# dmz (or internal network - if it is not masqueraded)?
# REQUIRES: FW_ROUTE
#
# With this option you may allow access to e.g. your mailserver. The
# machines must have valid, non-private, IP addresses which were assigned to
# you by your ISP. This opens a direct link to your network, so only use
# this option for access to your dmz!!!!
#
# Choice: leave empty (good choice!) or use the following explained syntax
# of forwarding rules, seperated each by a space.
# A forwarding rule consists of 1) source IP/net and 2) destination IP
# seperated by a comma. e.g. "1.1.1.1,2.2.2.2 3.3.3.3/16,4.4.4.4/24"
# Optional is a protocol, seperated by a comma, e.g. "5.5.5.5,6.6.6.6,igmp"
# Optional is a port after the protocol with a comma, e.g. "0/0,0/0,udp,514"
#
#FW_FORWARD="192.168.0.0/16,62.238.33.3/32"
FW_FORWARD=""
# Beware to use this!

#
# 14.)
# Which services accessed from the internet should be allowed to masqueraded
# servers (on the internal network or dmz)?
# REQUIRES: FW_ROUTE
#
# With this option you may allow access to e.g. your mailserver. The
# machines must be in a masqueraded segment and may not have public IP addesses!
# Hint: if FW_DEV_MASQ is set to the external interface you have to set
# FW_FORWARD from internal to DMZ for the service as well to allow access
# from internal!
#
# Please note that this should *not* be used for security reasons! You are
# opening a hole to your precious internal network. If e.g. the webserver there
# is compromised - your full internal network is compromised!!
#
# Choice: leave empty (good choice!) or use the following explained syntax
# of forward masquerade rules, seperated each by a space.
# A forward masquerade rule consists of 1) source IP/net, 2) destination IP
# (dmz/intern), 3) a protocol (tcp/udp only!) and 4) destination port,
# seperated by a comma (","), e.g. "4.0.0.0/8,1.1.1.1,tcp,80"
# Optional is a port after the destination port, to redirect the request to
# a different destination port on the destination IP, e.g.
# "4.0.0.0/8,1.1.1.1,tcp,80,81"
#
FW_FORWARD_MASQ=""
# Beware to use this!

#
# 15.)
# Which accesses to services should be redirected to a localport on the
# firewall machine?
#
# This can be used to force all internal users to surf via your squid proxy,
# or transparently redirect incoming webtraffic to a secure webserver.
#
# Choice: leave empty or use the following explained syntax of redirecting
# rules, seperated by a space.
# A redirecting rule consists of 1) source IP/net, 2) destination IP/net,
# 3) protocol (tcp or udp) 3) original destination port and 4) local port to
# redirect the traffic to, seperated by a colon. e.g.:
# "10.0.0.0/8,0/0,tcp,80,3128 0/0,172.20.1.1,tcp,80,8080"
#
FW_REDIRECT=""

#
# 16.)
# Which logging level should be enforced?
# You can define to log packets which were accepted or denied.
# You can also the set log level, the critical stuff or everything.
# Note that logging *_ALL is only for debugging purpose ...
#
# Choice: "yes" or "no", FW_LOG_*_CRIT defaults to "yes",
# FW_LOG_*_ALL defaults to "no"
#
FW_LOG_DROP_CRIT="no"
#
FW_LOG_DROP_ALL="no"
#
FW_LOG_ACCEPT_CRIT="no"
#
FW_LOG_ACCEPT_ALL="no"
#
# only change/activate this if you know what you are doing!
FW_LOG="--log-level warning --log-tcp-options --log-ip-option --log-prefix SuSE-FW"

#
# 17.)
# Do you want to enable additional kernel TCP/IP security features?
# If set to yes, some obscure kernel options are set.
# (icmp_ignore_bogus_error_responses, icmp_echoreply_rate,
# icmp_destunreach_rate, icmp_paramprob_rate, icmp_timeexeed_rate,
# ip_local_port_range, log_martians, mc_forwarding, mc_forwarding,
# rp_filter, routing flush)
# Tip: Set this to "no" until you have verified that you have got a
# configuration which works for you. Then set this to "yes" and keep it
# if everything still works. (It should!) ;-)
#
# Choice: "yes" or "no", defaults to "yes"
#
FW_KERNEL_SECURITY="no"

#
# 18.)
# Keep the routing set on, if the firewall rules are unloaded?
# REQUIRES: FW_ROUTE
#
# If you are using diald, or automatic dialing via ISDN, if packets need
# to be sent to the internet, you need to turn this on. The script will then
# not turn off routing and masquerading when stopped.
# You *might* also need this if you have got a DMZ.
# Please note that this is *insecure*! If you unload the rules, but are still
# connected, you might your internal network open to attacks!
# The better solution is to remove "/sbin/SuSEfirewall2 stop" or
# "/sbin/init.d/firewall stop" from the ip-down script!
#
#
# Choices "yes" or "no", defaults to "no"
#
FW_STOP_KEEP_ROUTING_STATE="no"

#
# 19.)
# Allow (or don't) ICMP echo pings on either the firewall or the dmz from
# the internet? The internet option is for allowing the DMZ and the internal
# network to ping the internet.
# REQUIRES: FW_ROUTE for FW_ALLOW_PING_DMZ and FW_ALLOW_PING_EXT
#
# Choice: "yes" or "no", defaults to "no" if not set
#
FW_ALLOW_PING_FW="yes"
#
FW_ALLOW_PING_DMZ="no"
#
FW_ALLOW_PING_EXT="no"

##
# END of rc.firewall
##

# #
#-------------------------------------------------------------------------#
# #
# EXPERT OPTIONS - all others please don't change these! #
# #
#-------------------------------------------------------------------------#
# #

#
# 20.)
# Allow (or don't) ICMP time-to-live-exceeded to be send from your firewall.
# This is used for traceroutes to your firewall (or traceroute like tools).
#
# Please note that the unix traceroute only works if you say "yes" to
# FW_ALLOW_INCOMING_HIGHPORTS_UDP, and windows traceroutes only if you say
# additionally "yes" to FW_ALLOW_PING_FW
#
# Choice: "yes" or "no", defaults to "no" if not set.
#
FW_ALLOW_FW_TRACEROUTE="yes"

#
# 21.)
# Allow ICMP sourcequench from your ISP?
#
# If set to yes, the firewall will notice when connection is choking, however
# this opens yourself to a denial of service attack. Choose your poison.
#
# Choice: "yes" or "no", defaults to "yes"
#
FW_ALLOW_FW_SOURCEQUENCH="yes"

#
# 22.)
# Allow/Ignore IP Broadcasts?
#
# If set to yes, the firewall will not filter broadcasts by default.
# This is needed e.g. for Netbios/Samba, RIP, OSPF where the broadcast
# option is used.
# If you do not want to allow them however ignore the annoying log entries,
# set FW_IGNORE_FW_BROADCAST to yes.
#
# Choice: "yes" or "no", defaults to "no" if not set.
#
FW_ALLOW_FW_BROADCAST="no"
#
FW_IGNORE_FW_BROADCAST="yes"

# Allow same class routing per default?
# REQUIRES: FW_ROUTE
#
# Do you want to allow routing between interfaces of the same class
# (e.g. between all internet interfaces, or all internal network interfaces)
# be default (so without the need setting up FW_FORWARD definitions)?
#
# Choice: "yes" or "no", defaults to "no"
#
FW_ALLOW_CLASS_ROUTING="no"

#
# 25.)
# Do you want to load customary rules from a file?
#
# This is really an expert option. NO HELP WILL BE GIVEN FOR THIS!
# READ THE EXAMPLE CUSTOMARY FILE AT /etc/sysconfig/scripts/SuSEfirewall2-custom
#

[ThaDude]

Ik heb de meegeleverde firewall ook niet aan de praat gekregen. Ik kreeg het NAT verhaal niet lekker werkende. Ik gebruik deze:

#!/bin/sh
#
# rc.firewall-2.4-stronger
FWVER=0.70s

# An example of a stronger IPTABLES firewall with IP Masquerade
# support for 2.4.x kernels.
#
# Log:
# 0.70s - Added a disabled examples for allowing internal DHCP
# and external WWW access to the server
# 0.63s - Added support for the IRC module
# 0.62s - Initial version based upon the basic 2.4.x rc.firewall


echo -e "\nLoading STRONGER rc.firewall - version $FWVER..\n"


#Setting the EXTERNAL and INTERNAL interfaces for the network
#
# Each IP Masquerade network needs to have at least one
# external and one internal network. The external network
# is where the natting will occur and the internal network
# should preferably be addressed with a RFC1918 private address
# scheme.
#
# For this example, "eth0" is external and "eth1" is internal"
#
# NOTE: If this doesnt EXACTLY fit your configuration, you must
# change the EXTIF or INTIF variables above. For example:
#
# EXTIF="ppp0"
#
# if you are a modem user.
#
EXTIF="eth0"
INTIF="eth1"
echo " External Interface: $EXTIF"
echo " Internal Interface: $INTIF"
echo " ---"

# Specify your Static IP address here or let the script take care of it
# for you.
#
# If you prefer to use STATIC addresses in your firewalls, un-# out the
# static example below and # out the dynamic line. If you don't care,
# just leave this section alone.
#
# If you have a DYNAMIC IP address, the ruleset already takes care of
# this for you. Please note that the different single and double quote
# characters and the script MATTER.
#
#
# DHCP users:
# -----------
# If you get your TCP/IP address via DHCP, **you will need ** to enable the
# #ed out command below underneath the PPP section AND replace the word
# "eth0" with the name of your EXTERNAL Internet connection (ppp0, ippp0,
# etc) on the lines for "ppp-ip" and "extip". You should also note that the
# DHCP server can and will change IP addresses on you. To deal with this,
# users should configure their DHCP client to re-run the rc.firewall ruleset
# everytime the DHCP lease is renewed.
#
# NOTE #1: Some DHCP clients like the original "pump" (the newer
# versions have been fixed) did NOT have the ability to run
# scripts after a lease-renew. Because of this, you need to
# replace it with something like "dhcpcd" or "dhclient".
#
# NOTE #2: The syntax for "dhcpcd" has changed in recent versions.
#
# Older versions used syntax like:
# dhcpcd -c /etc/rc.d/rc.firewall eth0
#
# Newer versions execute a file called /etc/dhcpc/dhcpcd-eth0.exe
#
# NOTE #3: For Pump users, put the following line in /etc/pump.conf:
#
# script /etc/rc.d/rc.firewall
#
# PPP users:
# ----------
# If you aren't already aware, the /etc/ppp/ip-up script is always run when
# a PPP connection comes up. Because of this, we can make the ruleset go and
# get the new PPP IP address and update the strong firewall ruleset.
#
# If the /etc/ppp/ip-up file already exists, you should edit it and add a line
# containing "/etc/rc.d/rc.firewall" near the end of the file.
#
# If you don't already have a /etc/ppp/ip-up sccript, you need to create the
# following link to run the /etc/rc.d/rc.firewall script.
#
# ln -s /etc/rc.d/rc.firewall /etc/ppp/ip-up
#
# * You then want to enable the #ed out shell command below *
#
#
# Determine the external IP automatically:
# ----------------------------------------
#
EXTIP="`/sbin/ifconfig $EXTIF | grep 'inet addr' | awk '{print $2}' | sed -e 's/.*://'`"

# For users who wish to use STATIC IP addresses:
#
# # out the EXTIP line above and un-# out the EXTIP line below
#
#EXTIP="your.static.PPP.address"
echo " External IP: $EXTIP"
echo " ---"


# Assign the internal TCP/IP network and IP address
INTNET="192.168.0.1/24"
INTIP="192.168.0.1/24"
echo " Internal Network: $INTNET"
echo " Internal IP: $INTIP"
echo " ---"


# The location of various iptables and other shell programs
#
# If your Linux distribution came with a copy of iptables, most
# likely it is located in /sbin. If you manually compiled
# iptables, the default location is in /usr/local/sbin
#
# ** Please use the "whereis iptables" command to figure out
# ** where your copy is and change the path below to reflect
# ** your setup
#
#IPTABLES=/sbin/iptables
IPTABLES=/usr/sbin/iptables
#
LSMOD=/sbin/lsmod
GREP=/bin/grep
AWK=/bin/awk


# Setting a few other local variables
#
UNIVERSE="0.0.0.0/0"

#======================================================================
#== No editing beyond this line is required for initial MASQ testing ==

# Need to verify that all modules have all required dependencies
#
echo " - Verifying that all kernel modules are ok"
/sbin/depmod -a

echo -en " Loading kernel modules: "

# With the new IPTABLES code, the core MASQ functionality is now either
# modular or compiled into the kernel. This HOWTO shows ALL IPTABLES
# options as MODULES. If your kernel is compiled correctly, there is
# NO need to load the kernel modules manually.
#
# NOTE: The following items are listed ONLY for informational reasons.
# There is no reason to manual load these modules unless your
# kernel is either mis-configured or you intentionally disabled
# the kernel module autoloader.
#

# Upon the commands of starting up IP Masq on the server, the
# following kernel modules will be automatically loaded:
#
# NOTE: Only load the IP MASQ modules you need. All current IP MASQ
# modules are shown below but are commented out from loading.
# ===============================================================

#Load the main body of the IPTABLES module - "ip_tables"
# - Loaded automatically when the "iptables" command is invoked
#
# - Loaded manually to clean up kernel auto-loading timing issues
#
echo -en "ip_tables, "
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP ip_tables | $AWK {'print $1'} `" ]; then
/sbin/insmod ip_tables
fi


#Load the IPTABLES filtering module - "iptable_filter"
#
# - Loaded automatically when filter policies are activated


#Load the stateful connection tracking framework - "ip_conntrack"
#
# The conntrack module in itself does nothing without other specific
# conntrack modules being loaded afterwards such as the "ip_conntrack_ftp"
# module
#
# - This module is loaded automatically when MASQ functionality is
# enabled
#
# - Loaded manually to clean up kernel auto-loading timing issues
#
echo -en "ip_conntrack, "
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP ip_conntrack | $AWK {'print $1'} `" ]; then
/sbin/insmod ip_conntrack
fi


#Load the FTP tracking mechanism for full FTP tracking
#
# Enabled by default -- insert a "#" on the next line to deactivate
#
echo -e "ip_conntrack_ftp, "
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP ip_conntrack_ftp | $AWK {'print $1'} `" ]; then
/sbin/insmod ip_conntrack_ftp
fi


#Load the IRC tracking mechanism for full IRC tracking
#
# Enabled by default -- insert a "#" on the next line to deactivate
#
echo -en " ip_conntrack_irc, "
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP ip_conntrack_irc | $AWK {'print $1'} `" ]; then
/sbin/insmod ip_conntrack_irc
fi


#Load the general IPTABLES NAT code - "iptable_nat"
# - Loaded automatically when MASQ functionality is turned on
#
# - Loaded manually to clean up kernel auto-loading timing issues
#
echo -en "iptable_nat, "
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP iptable_nat | $AWK {'print $1'} `" ]; then
/sbin/insmod iptable_nat
fi


#Loads the FTP NAT functionality into the core IPTABLES code
# Required to support non-PASV FTP.
#
# Enabled by default -- insert a "#" on the next line to deactivate
#
echo -e "ip_nat_ftp"
#
#Verify the module isn't loaded. If it is, skip it
#
if [ -z "` $LSMOD | $GREP ip_nat_ftp | $AWK {'print $1'} `" ]; then
/sbin/insmod ip_nat_ftp
fi

echo " ---"

# Just to be complete, here is a list of the remaining kernel modules
# and their function. Please note that several modules should be only
# loaded by the correct master kernel module for proper operation.
# --------------------------------------------------------------------
#
# ipt_mark - this target marks a given packet for future action.
# This automatically loads the ipt_MARK module
#
# ipt_tcpmss - this target allows to manipulate the TCP MSS
# option for braindead remote firewalls.
# This automatically loads the ipt_TCPMSS module
#
# ipt_limit - this target allows for packets to be limited to
# to many hits per sec/min/hr
#
# ipt_multiport - this match allows for targets within a range
# of port numbers vs. listing each port individually
#
# ipt_state - this match allows to catch packets with various
# IP and TCP flags set/unset
#
# ipt_unclean - this match allows to catch packets that have invalid
# IP/TCP flags set
#
# iptable_filter - this module allows for packets to be DROPped,
# REJECTed, or LOGged. This module automatically
# loads the following modules:
#
# ipt_LOG - this target allows for packets to be
# logged
#
# ipt_REJECT - this target DROPs the packet and returns
# a configurable ICMP packet back to the
# sender.
#
# iptable_mangle - this target allows for packets to be manipulated
# for things like the TCPMSS option, etc.


#CRITICAL: Enable IP forwarding since it is disabled by default since
#
# Redhat Users: you may try changing the options in
# /etc/sysconfig/network from:
#
# FORWARD_IPV4=false
# to
# FORWARD_IPV4=true
#
echo " Enabling forwarding.."
echo "1" > /proc/sys/net/ipv4/ip_forward


# Dynamic IP users:
#
# If you get your IP address dynamically from SLIP, PPP, or DHCP,
# enable the following option. This enables dynamic-address hacking
# which makes the life with Diald and similar programs much easier.
#
echo " Enabling DynamicAddr.."
echo "1" > /proc/sys/net/ipv4/ip_dynaddr

echo " ---"

#############################################################################
#
# Enable Stronger IP forwarding and Masquerading
#
# NOTE: In IPTABLES speak, IP Masquerading is a form of SourceNAT or SNAT.
#
# NOTE #2: The following is an example for an internal LAN address in the
# 192.168.1.x network with a 255.255.255.0 or a "24" bit subnet
# mask connecting to the Internet on external interface "eth0".
# This example will MASQ internal traffic out to the Internet
# but not allow non-initiated traffic into your internal network.
#
#
# ** Please change the above network numbers, subnet mask, and your
# *** Internet connection interface name to match your setup
#

#Clearing any previous configuration
#
# Unless specified, the defaults for INPUT, OUTPUT, and FORWARD to DROP.
#
# You CANNOT change this to REJECT as it isn't a vaild setting for a
# policy. If you want REJECT, you must explictly REJECT at the end
# of a giving INPUT, OUTPUT, or FORWARD chain
#
echo " Clearing any existing rules and setting default policy to DROP.."
$IPTABLES -P INPUT DROP
$IPTABLES -F INPUT
$IPTABLES -P OUTPUT DROP
$IPTABLES -F OUTPUT
$IPTABLES -P FORWARD DROP
$IPTABLES -F FORWARD
$IPTABLES -F -t nat
#Not needed and it will only load the unneeded kernel module
#$IPTABLES -F -t mangle
#
# Flush the user chain.. if it exists
if [ -n "`$IPTABLES -L | $GREP drop-and-log-it`" ]; then
$IPTABLES -F drop-and-log-it
fi
#
# Delete all User-specified chains
$IPTABLES -X
#
# Reset all IPTABLES counters
$IPTABLES -Z


#Configuring specific CHAINS for later use in the ruleset
#
# NOTE: Some users prefer to have their firewall silently
# "DROP" packets while others prefer to use "REJECT"
# to send ICMP error messages back to the remote
# machine. The default is "REJECT" but feel free to
# change this below.
#
# NOTE: Without the --log-level set to "info", every single
# firewall hit will goto ALL vtys. This is a very big
# pain.
#
echo " Creating a DROP chain.."
$IPTABLES -N drop-and-log-it
$IPTABLES -A drop-and-log-it -j LOG --log-level info
$IPTABLES -A drop-and-log-it -j DROP

echo -e "\n - Loading INPUT rulesets"


#######################################################################
# INPUT: Incoming traffic from various interfaces. All rulesets are
# already flushed and set to a default policy of DROP.
#

# loopback interfaces are valid.
#
$IPTABLES -A INPUT -i lo -s $UNIVERSE -d $UNIVERSE -j ACCEPT


# local interface, local machines, going anywhere is valid
#
$IPTABLES -A INPUT -i $INTIF -s $INTNET -d $UNIVERSE -j ACCEPT


# remote interface, claiming to be local machines, IP spoofing, get lost
#
$IPTABLES -A INPUT -i $EXTIF -s $INTNET -d $UNIVERSE -j drop-and-log-it


# external interface, from any source, for ICMP traffic is valid
#
# If you would like your machine to "ping" from the Internet,
# enable this next line
#
$IPTABLES -A INPUT -i $EXTIF -p ICMP -s $UNIVERSE -d $EXTIP -j ACCEPT


# remote interface, any source, going to permanent PPP address is valid
#
#$IPTABLES -A INPUT -i $EXTIF -s $UNIVERSE -d $EXTIP -j ACCEPT


# Allow any related traffic coming back to the MASQ server in
#
$IPTABLES -A INPUT -i $EXTIF -s $UNIVERSE -d $EXTIP -m state --state \
ESTABLISHED,RELATED -j ACCEPT


# ----- Begin OPTIONAL Section -----
#

# DHCPd - Enable the following lines if you run an INTERNAL DHCPd server
#
#$IPTABLES -A INPUT -i $INTIF -p tcp --sport 68 --dport 67 -j ACCEPT
#$IPTABLES -A INPUT -i $INTIF -p udp --sport 68 --dport 67 -j ACCEPT

# HTTPd - Enable the following lines if you run an EXTERNAL WWW server
#
echo -e " - Allowing EXTERNAL access to the FTP server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 21 -j ACCEPT

echo -e " - Allowing EXTERNAL access to the SSH server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 22 -j ACCEPT

echo -e " - Allowing EXTERNAL access to the SMTP server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 25 -j ACCEPT

#echo -e " - Allowing EXTERNAL access to the DOMAIN server"
#$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
#-p tcp -s $UNIVERSE -d $EXTIP --dport 53 -j ACCEPT

echo -e " - Allowing EXTERNAL access to the WWW server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 80 -j ACCEPT

#echo -e " - Allowing EXTERNAL access to the POP3 server"
#$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
#-p tcp -s $UNIVERSE -d $EXTIP --dport 110 -j ACCEPT

#echo -e " - Allowing EXTERNAL access to the SSL server"
#$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
#-p tcp -s $UNIVERSE -d $EXTIP --dport 443 -j ACCEPT

echo -e " - Allowing EXTERNAL access to the PROXY server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 2064 -j ACCEPT

#echo -e " - Allowing EXTERNAL access to the WEBMIN server"
#$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
#-p tcp -s $UNIVERSE -d $EXTIP --dport 3306 -j ACCEPT

echo -e " - Allowing EXTERNAL access to the WEBMIN server"
$IPTABLES -A INPUT -i $EXTIF -m state --state NEW,ESTABLISHED,RELATED \
-p tcp -s $UNIVERSE -d $EXTIP --dport 10000 -j ACCEPT













#
# ----- End OPTIONAL Section -----



# Catch all rule, all other incoming is denied and logged.
#
$IPTABLES -A INPUT -s $UNIVERSE -d $UNIVERSE -j drop-and-log-it


echo -e " - Loading OUTPUT rulesets"

#######################################################################
# OUTPUT: Outgoing traffic from various interfaces. All rulesets are
# already flushed and set to a default policy of DROP.
#

# loopback interface is valid.
#
$IPTABLES -A OUTPUT -o lo -s $UNIVERSE -d $UNIVERSE -j ACCEPT


# local interfaces, any source going to local net is valid
#
$IPTABLES -A OUTPUT -o $INTIF -s $EXTIP -d $INTNET -j ACCEPT


# local interface, any source going to local net is valid
#
$IPTABLES -A OUTPUT -o $INTIF -s $INTIP -d $INTNET -j ACCEPT


# outgoing to local net on remote interface, stuffed routing, deny
#
$IPTABLES -A OUTPUT -o $EXTIF -s $UNIVERSE -d $INTNET -j drop-and-log-it


# anything else outgoing on remote interface is valid
#
$IPTABLES -A OUTPUT -o $EXTIF -s $EXTIP -d $UNIVERSE -j ACCEPT


# DHCPd - Enable the following lines if you run an INTERNAL DHCPd server
#
#$IPTABLES -A OUTPUT -o $INTIF -p tcp -s $INTIP --sport 67 \
#-d 255.255.255.255 --dport 68 -j ACCEPT
#$IPTABLES -A OUTPUT -o $INTIF -p udp -s $INTIP --sport 67 \
#-d 255.255.255.255 --dport 68 -j ACCEPT


# Catch all rule, all other outgoing is denied and logged.
#
$IPTABLES -A OUTPUT -s $UNIVERSE -d $UNIVERSE -j drop-and-log-it


echo -e " - Loading FORWARD rulesets"

#######################################################################
# FORWARD: Enable Forwarding and thus IPMASQ
#

echo " - FWD: Allow all connections OUT and only existing/related IN"
$IPTABLES -A FORWARD -i $EXTIF -o $INTIF -m state --state ESTABLISHED,RELATED \
-j ACCEPT
$IPTABLES -A FORWARD -i $INTIF -o $EXTIF -j ACCEPT

# Catch all rule, all other forwarding is denied and logged.
#
$IPTABLES -A FORWARD -j drop-and-log-it


echo " - NAT: Enabling SNAT (MASQUERADE) functionality on $EXTIF"
#
#More liberal form
#$IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE
#
#Stricter form
$IPTABLES -t nat -A POSTROUTING -o $EXTIF -j SNAT --to $EXTIP


#######################################################################


echo -e "\nDone.\n"


Enige vervelende van deze is je firewall.log deze wordt emens groot.. Maar deze delete ik gewoon

[Verwijderd]

nou dat ga ik ook maar eens proberen dan.

Kun je met dat script ook 2 interne netwerken instellen? Als ik het script zo zie denk ik niet dat INTIF='eth1 eth2' gaat werken.
Eventueel kan ik wel gewoon overal een regel tussenvoegen waar de INTIF variabele wordt gebruikt denk ik.... ? INT2IF ofzo.

[RvdH]

Als het nog niet werkt zou ik als ik jou was eens Firewall Builder proberen.. ideaal tooltje

[Verwijderd]

YES! nou werkt het tenminste goed voor 1 segemnt.
Dan weet ik in elk geval zeker dat het aan het firwallscript van SuSE ligt.

NAT dus inderdaad. Ik denk dat ik al weet wat ik aan het script moet toevoegen.

iptables -t nat -A POSTROUTING -o <extip> -j SNAT --to <extip>

Dank voor hulp en tips!