#echo 1 > /proc/sys/net/ipv4/ip_forward

-A FORWARD -o $LAN_IF -j ACCEPT
-A POSTROUTING -o $EXT_IF -j MASQUERADE

#iptables -t nat -A POSTROUTING -o $EXT_IF -j MASQUERADE

touch /etc/sysconfig/firewall.sh
chmod +x /etc/sysconfig/firewall.sh
chmod 750 /etc/sysconfig/firewall.sh
vi /etc/sysconfig/firewall.sh

#!/bin/bash
# Очистка всех цепочек iptables
iptables -F
iptables -F -t nat
iptables -F -t mangle
iptables -X
iptables -t nat -X
iptables -t mangle -X

# Политика по умолчанию, запретить все что не разрешено
iptables -P INPUT DROP
iptables -P OUTPUT DROP
iptables -P FORWARD DROP

# Разрешаем обращение к lo интерфейсу
iptables -A INPUT -i lo -p all -j ACCEPT
iptables -A OUTPUT -o lo -p all -j ACCEPT

# Разрешаем обращение к внутреннему eth0 интерфейсу
iptables -A INPUT -i eth0 -p all -j ACCEPT
iptables -A OUTPUT -o eth0 -p all  -j ACCEPT

# Пропускать уже инициорванные, а также их дочерние
iptables -A INPUT -p all -m state --state ESTABLISHED,RELATED -j ACCEPT

# Пропускать новые, иницированные, а также их дочерние
iptables -A OUTPUT -p all -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

# Разрешить форвардинг для новых, иницированных, а также их дочерних
iptables -A FORWARD -p all -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

# Настройка NAT
iptables -t nat -A POSTROUTING -s 192.168.137.0/24 -j MASQUERADE

/etc/sysconfig/firewall.sh

#!/bin/bash
# Очистка всех цепочек iptables
iptables -F
iptables -F -t nat
iptables -F -t mangle
iptables -X
iptables -t nat -X
iptables -t mangle -X

# Политика по умолчанию,запретить все что не разрешено
iptables -P INPUT DROP
iptables -P OUTPUT DROP
iptables -P FORWARD DROP

# Разрешаем обращение к lo интерфейсу
iptables -A INPUT -i lo -p all -j ACCEPT
iptables -A OUTPUT -o lo -p all -j ACCEPT

# Разрешаем обращение к внутреннему eth0 интерфейсу
iptables -A INPUT -i eth0 -p all -j ACCEPT
iptables -A OUTPUT -o eth0 -p all -j ACCEPT

# Пропускать уже инициированные, а также их дочерние
iptables -A INPUT -p all -m state --state ESTABLISHED,RELATED -j ACCEPT

# Пропускать новые, инициированные, а также их дочерние
iptables -A OUTPUT -p all -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

# Разрешить форвардинг для новых,инициированных, а также их дочерних
iptables -A FORWARD -p all -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT


# Настройка NAT
iptables -t nat -A PREROUTING -s 192.168.137.0/24 -p tcp -m tcp --dport 80 -j REDIRECT --to-port 3128

#
# Recommended minimum configuration:
#
acl manager proto cache_object
acl localhost src 127.0.0.1/32 ::1
acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1

# Example rule allowing access from your local networks.
# Adapt to list your (internal) IP networks from where browsing
# should be allowed
acl localnet src 10.0.0.0/8    # RFC1918 possible internal network
acl localnet src 172.16.0.0/12    # RFC1918 possible internal network
acl localnet src 192.168.0.0/16    # RFC1918 possible internal network
acl localnet src fc00::/7       # RFC 4193 local private network range
acl localnet src fe80::/10      # RFC 4291 link-local (directly plugged) machines


acl SSL_ports port 443
acl Safe_ports port 80        # http
acl Safe_ports port 21        # ftp
acl Safe_ports port 443        # https
acl Safe_ports port 70        # gopher
acl Safe_ports port 210        # wais
acl Safe_ports port 1025-65535    # unregistered ports
acl Safe_ports port 280        # http-mgmt
acl Safe_ports port 488        # gss-http
acl Safe_ports port 591        # filemaker
acl Safe_ports port 777        # multiling http
acl CONNECT method CONNECT

#
# Recommended minimum Access Permission configuration:
#
# Only allow cachemgr access from localhost
http_access allow manager localhost
http_access deny manager

# Deny requests to certain unsafe ports
http_access deny !Safe_ports

# Deny CONNECT to other than secure SSL ports
http_access deny CONNECT !SSL_ports

# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on "localhost" is a local user
#http_access deny to_localhost

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#

acl MyLocal src 192.168.137.0/24 # МОЯ ЛОКАЛКА
acl MyProtocol proto http
http_access allow MyProtocol Safe_ports
http_access allow MyLocal    

# Example rule allowing access from your local networks.
# Adapt localnet in the ACL section to list your (internal) IP networks
# from where browsing should be allowed
http_access allow localnet
http_access allow localhost

# And finally deny all other access to this proxy
http_access deny all

# Squid normally listens to port 3128
http_port 3128 transparent

# We recommend you to use at least the following line.
hierarchy_stoplist cgi-bin ?

# Uncomment and adjust the following to add a disk cache directory.
#cache_dir ufs /var/spool/squid 100 16 256

# Leave coredumps in the first cache dir
coredump_dir /var/spool/squid

# Add any of your own refresh_pattern entries above these.
refresh_pattern ^ftp:        1440    20%    10080
refresh_pattern ^gopher:    1440    0%    1440
refresh_pattern -i (/cgi-bin/|\?) 0    0%    0
refresh_pattern .        0    20%    4320