echo -e „nnAlapveto Internetmegosztas inditasa v. $FWVER..n”

# A parancsok helye
#
# ** Hasznald „whereis iptables” vagy a „which iptables”
# ** parancsot hogy kitalald hol is van az iptables program
#

IPTABLES=/sbin/iptables
DEPMOD=/sbin/depmod
MODPROBE=/sbin/modprobe

# Kulso es belso eszkozok beallitasa
#
#  Ebben a peldaban „eth0” a kulso es „eth1″ a belso
#
#  Ha ADSL-t vagy analog modemet hasznalsz akkor valoszinuleg
#  EXTIF=”ppp0” kell hogy legyen
#  hasznald az „ifconfig” parancsot
#
EXTIF=”eth0″
INTIF=”eth1″
echo ”  Kulso eszkoz:  $EXTIF”
echo ”  Belso eszkoz:  $INTIF”

#===========================================================
#== Ezalatt a vonal alatt mar semmit sem kell beallitanod ==

echo -en ”  modulok betoltese: ”

# Need to verify that all modules have all required dependencies
#
echo ”  – Kernel modulok vizsgalata”
$DEPMOD -a

# 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.
# ===============================================================

echo „———————————————————————-”

#Load the main body of the IPTABLES module – „iptable”
#  – Loaded automatically when the „iptables” command is invoked
#
#  – Loaded manually to clean up kernel auto-loading timing issues
#
echo -en „ip_tables, ”
$MODPROBE ip_tables

#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, ”
$MODPROBE ip_conntrack

#Load the FTP tracking mechanism for full FTP tracking
#
# Enabled by default — insert a „#” on the next line to deactivate
#
echo -en „ip_conntrack_ftp, ”
$MODPROBE ip_conntrack_ftp

#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, ”
$MODPROBE ip_conntrack_irc

#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, ”
$MODPROBE iptable_nat

#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 -en „ip_nat_ftp, ”
$MODPROBE ip_nat_ftp

#Loads the IRC NAT functionality into the core IPTABLES code
# Require to support NAT of IRC DCC requests
#
# Disabled by default — remove the „#” on the next line to activate
#
#echo -e „ip_nat_irc”
#$MODPROBE ip_nat_irc

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.

echo -e ”  Modulok betoltese kesz.n”

#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 ”  Ip tovabbitas engedelyezese..”
echo „1” > /proc/sys/net/ipv4/ip_forward

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

# Enable simple 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
#            192.168.0.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 and OUTPUT is ACCEPT
#    The default for FORWARD is DROP (REJECT is not a valid policy)
#
echo ”  Alapveto atiranyitasok beallitasa..”
$IPTABLES -P INPUT ACCEPT
$IPTABLES -F INPUT
$IPTABLES -P OUTPUT ACCEPT
$IPTABLES -F OUTPUT
$IPTABLES -P FORWARD DROP
$IPTABLES -F FORWARD
$IPTABLES -t nat -F

#echo ”  Csak Belulrol letrehozott kapcsolatok engedelyezese”
#$IPTABLES -A FORWARD -i $EXTIF -o $INTIF -m state –state ESTABLISHED,RELATED -j ACCEPT
#$IPTABLES -A FORWARD -i $INTIF -o $EXTIF -j ACCEPT
#$IPTABLES -A FORWARD -j LOG

echo ”  Ip maszkolas engedejezese a $EXTIF eszkozon”
$IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE

# MTU problema
# HA ADSL-unk van szedjuk ki a kovetkezozo sort a megjegyzesbol
#$IPTABLES -t nat -A POSTROUTING -o $EXTIF -p tcp –tcp-flags SYN,RST SYN -m tcpmss –mss 1453: -j TCPMSS –set-mss 1452

echo -e „KESZ.n”