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#
# /etc/bastille-firewall.cfg
#
# Configuration file for both 2.2/ipchains and 2.4/netfilter scripts
#
# $Source: /cvsroot/bastille-linux/dev/working_tree/Bastille/bastille-firewall.cfg,v $
# Modified by: $Author: peterw $
# $Date: 2002/01/04 13:34:18 $
# $Revision: 1.7 $
#
# Copyright (C) 1999-2001 Peter Watkins
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# Thanks to David Ranch, Brad A, Don G, and others for their suggestions

# the configuration values should be whitespace-delimited lists of
# appropriate values, e.g.
#         TCP_PUBLIC_SERVICES="80 smtp ssh"
# lists Web (port 80), SMTP mail, and Secure Shell ports
#
# This script is suitable for workstations or simple NAT firewalls;
# you may want to add more "output" restrictions for serious servers

# 0) DNS servers (Linux 2.2/ipchains only)
#        You must list your DNS servers here so that
#        the firewall will allow them to service your lookup requests
#
# List of DNS servers/networks to allow "domain" responses from
# This _could_ be nameservers as a list of <ip-address>/32 entries
#DNS_SERVERS="a.b.c.d/32 e.f.g.h/32"
# If you are running a caching nameserver, you'll need to allow from
# "0.0.0.0/0" so named can query any arbitrary nameserver
# (To enable a caching nameserver, you will also probably need to
#  add "domain" to the TCP and UDP public service lists.)
#DNS_SERVERS="0.0.0.0/0"
#
# To have the DNS servers parsed from /etc/resolv.conf at runtime,
# as normal workstations will want, make this variable empty
#DNS_SERVERS=""
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
DNS_SERVERS="{DNS_SERVERS}"


# 1) define your interfaces (all systems)
#        Note a "+" acts as a wildcard, e.g. ppp+ would match any PPP
#        interface
#
# list internal/trusted interfaces
# traffic from these interfaces will be allowed
# through the firewall, no restrictions
#TRUSTED_IFACES="lo"                                        # MINIMAL/SAFEST
#
# list external/untrusted interfaces
#PUBLIC_IFACES="eth+ ppp+ slip+"                        # SAFEST
#
# list internal/partially-trusted interfaces
# e.g. if this acts as a NAT/IP Masq server and you
# don't want clients on those interfaces having
# full network access to services running on this
# server (as the TRUSTED_IFACES allows)
#INTERNAL_IFACES=""                                # SAFEST
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
TRUSTED_IFACES="lo"                                        # MINIMAL/SAFEST
PUBLIC_IFACES="eth+ ppp+ slip+ venet+ bond+"                        # SAFEST
INTERNAL_IFACES=""                                # SAFEST


# 2) services for which we want to log access attempts to syslog (all systems)
#        Note this only audits connection attempts from public interfaces
#
#        Also see item 12, LOG_FAILURES
#
#TCP_AUDIT_SERVICES="telnet ftp imap pop3 finger sunrpc exec login linuxconf ssh"
# anyone probing for BackOrifice?
#UDP_AUDIT_SERVICES="31337"
# how about ICMP?
#ICMP_AUDIT_TYPES=""
#ICMP_AUDIT_TYPES="echo-request"        # ping/MS tracert
#
# To enable auditing, you must have syslog configured to log "kern"
# messages of "info" level; typically you'd do this with a line in
# syslog.conf like
#   kern.info                                /var/log/messages
# though the Bastille port monitor will normally want these messages
# logged to a named pipe instead, and the Bastille script normally
# configures syslog for "kern.*" which catches these messages
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
#TCP_AUDIT_SERVICES="telnet ftp imap pop3 finger sunrpc exec login linuxconf ssh"
#UDP_AUDIT_SERVICES="31337"
#ICMP_AUDIT_TYPES=""


# 3) services we allow connections to (all systems)
#
# FTP note:
#        To allow your machine to service "passive" FTP clients,
#        you will need to make allowances for the passive data
#        ports; Bastille users should read README.FTP for more
#        information
#
# "public" interfaces:
# TCP services that "public" hosts should be allowed to connect to
#TCP_PUBLIC_SERVICES=""                                        # MINIMAL/SAFEST
#
# UDP services that "public" hosts should be allowed to connect to
#UDP_PUBLIC_SERVICES=""                                        # MINIMAL/SAFEST
#
# "internal" interfaces:
# (NB: you will need to repeat the "public" services if you want
#      to allow "internal" hosts to reach those services, too.)
# TCP services that internal clients can connect to
#TCP_INTERNAL_SERVICES=""                                # MINIMAL/SAFEST
#
# UDP services that internal clients can connect to
#UDP_INTERNAL_SERVICES=""                                # MINIMAL/SAFEST
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
TCP_PUBLIC_SERVICES="{TCP_PUBLIC_SERVICES}"                                        # MINIMAL/SAFEST
UDP_PUBLIC_SERVICES="{UDP_PUBLIC_SERVICES}"                                        # MINIMAL/SAFEST
TCP_INTERNAL_SERVICES=""                                # MINIMAL/SAFEST
UDP_INTERNAL_SERVICES=""                                # MINIMAL/SAFEST

# 4) passive/active FTP (Linux 2.2/ipchains only)
#        FTP is a firewall nightmare; if you allow "normal" FTP connections,
#        you must be careful to block any TCP services that are listening
#        on high ports; it's safer to require your FTP clients to use
#        "passive" mode.
#
#        Note this will also force clients on machines
#        that use this one for NAT/IP Masquerading to use passive mode
#        for connections that go through this server (e.g. from the
#        internal network to public Internet machines
#
#        For more information about FTP, see the Bastille README.FTP doc
#
#FORCE_PASV_FTP="N"
#FORCE_PASV_FTP="Y"                                        # SAFEST
#
FORCE_PASV_FTP="Y"                                        # SAFEST


# 5) Services to explicitly block. (Linux 2.2/ipchains only)
#        See FTP note above
#        Note that ranges of ports are specified with colons, and you
#        can specify an open range by using only one number, e.g.
#        1024: means ports >= 1024 and :6000 means ports <= 6000
#
# TCP services on high ports that should be blocked if not forcing passive FTP
# This should include X (6000:6010) and anything else revealed by 'netstat -an'
#  (this does not matter unless you're not forcing "passive" FTP)
#TCP_BLOCKED_SERVICES="6000:6020"
#
# UDP services to block: this should be UDP services on high ports.
# Your only vulnerability from public interfaces are the DNS and
# NTP servers/networks (those with 0.0.0.0 for DNS servers should
# obviously be very careful here!)
#UDP_BLOCKED_SERVICES="2049"
#
# types of ICMP packets to allow
#ICMP_ALLOWED_TYPES="destination-unreachable"                # MINIMAL/SAFEST
# the following allows you to ping/traceroute outbound
#ICMP_ALLOWED_TYPES="destination-unreachable echo-reply time-exceeded"
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
TCP_BLOCKED_SERVICES="6000:6020"
UDP_BLOCKED_SERVICES="2049"
ICMP_ALLOWED_TYPES="destination-unreachable echo-reply time-exceeded echo-request"


# 6) Source Address Verification (all Linux systems)
#        This helps prevent "IP Spoofing" attacks
#
ENABLE_SRC_ADDR_VERIFY="Y"                                # SAFEST


# 7) IP Masquerading / NAT. (all systems)
#        List your internal/masq'ed networks here
#
#        Also see item 4, FORCE_PASV_FTP, as that setting affects
#        clients using IP Masquerading through this machine
#
# Set this variable if you're using IP Masq / NAT for a local network
#IP_MASQ_NETWORK=""                                        # DISABLE/SAFEST
#IP_MASQ_NETWORK="10.0.0.0/8"                                # example
#IP_MASQ_NETWORK="192.168.0.0/16"                        # example
#
# Have lots of masq hosts? uncomment the following six lines
#  and list the hosts/networks in /etc/firewall-masqhosts
#  the script assumes any address without a "/" netmask afterwards
#  is an individual address (netmask /255.255.255.255):
#if [ -f /etc/firewall-masqhosts ]; then
#  echo "Reading list of masq hosts from /etc/firewall-masqhosts"
#  # Read the file, but use 'awk' to strip comments
#  # Note the sed bracket phrase includes a space and tab char
#  IP_MASQ_NETWORK=`cat /etc/firewall-masqhosts | awk -F\# '/\// {print $1; next} /[0-9]/ {print $1"/32"}' |sed 's:[         ]*::g'`
#fi
#
# Masq modules
# NB: The script will prepend "ip_masq_" to each module name
#IP_MASQ_MODULES="cuseeme ftp irc quake raudio vdolive"        # ALL (?)
#IP_MASQ_MODULES="ftp raudio vdolive"                        # RECOMMENDED
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
IP_MASQ_NETWORK=""                                        # DISABLE/SAFEST
IP_MASQ_MODULES="ftp raudio vdolive"                        # RECOMMENDED


# 8) How to react to disallowed packets (all systems)
# whether to "REJECT" or "DROP" disallowed packets; if you're running any
# public services, you probably ought to use "REJECT"; if in serious stealth
# mode, choose "DROP" so simple probes don't know if there's anything out there
#        NOTE: disallowed ICMP packets are discarded with "DROP", as
#                it would not make sense to "reject" the packet if you're
#                trying to disallow ping/traceroute
#        NOTE: the scripts that set up the filter rules will interpret these
#                keywords as needed, e.g. "DROP" becomes "DENY" for Linux 2.2/ipchains
#
REJECT_METHOD="DROP"


# 9) DHCP (Linux 2.2/ipchains only)
#    In case your server needs to get a DHCP address from some other
#    machine (e.g. cable modem)
#DHCP_IFACES="eth0"                        # example, to allow you to query on eth0
#DHCP_IFACES=""                                # DISABLED
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
DHCP_IFACES=""                                # DISABLED


# 10) NTP servers (Linux 2.2/ipchains only)
#        more UDP fun. List IP addresses or network space of NTP servers
#
#NTP_SERVERS=""                                # DISABLE NTP QUERIES / SAFEST
#NTP_SERVERS="a.b.c.d/32 e.f.g.h/32"        # example, to allow querying 2 servers
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
NTP_SERVERS=""                                # DISABLE NTP QUERIES / SAFEST


# 11) more ICMP. (Linux 2.2/ipchains only)
#        Control the outbound ICMP to make yourself invisible to
#        traceroute probes
#
#ICMP_OUTBOUND_DISABLED_TYPES="destination-unreachable time-exceeded"
#
# Please make sure variable assignments are on single lines; do NOT
# use the "\" continuation character (so Bastille can change the
# values if it is run more than once)
ICMP_OUTBOUND_DISABLED_TYPES="destination-unreachable time-exceeded"


# 12) Logging (all systems)
#        With this enabled, ipchains will log all blocked packets.
#                 ** this could generate huge logs **
#        This is primarily intended for the port mointoring system;
#        also note that you probably do not want to "AUDIT" any services
#        that you are not allowing, as doing so would mean duplicate
#        logging
LOG_FAILURES="N"                                # do not log blocked packets

# 13) Block fragmented packets (all systems)
#       There's no good reason to allow these
#ALLOW_FRAGMENTS="N"                                # safest
ALLOW_FRAGMENTS="Y"                                # old behavior

# 14) Prevent SMB broadcasts from leaking out NAT setup (all systems)
#        Windows machines will poll teh net with SMB broadcasts,
#        basically advertising their existence. Most folks agree
#        that this traffic should be dropped
#DROP_SMB_NAT_BCAST="N"                # allow them (are you sure?)
DROP_SMB_NAT_BCAST="Y"                # drop those packets

# 15) Log level (iptables/netfilter/Linux 2.4 only)
#        Control what level of logging is used when the firewall logs
#        information. Default is warning (4). Lowest priority is
#        debug (7); highest is emergency (0). To prevent syslog
#        from copying iptables error messages to the console, set
#        this to 6 (7 would also work, but 6 is recommended)
#        You can also stop syslogd/klogd from printing kernel
#        messages to the console by issuing the command
#          setterm -msg off
#IP_LOG_LEVEL=6                        # level used in 2.2/ipchains
IP_LOG_LEVEL=4                        # iptables/netfilter default

# 16) Always attempt to use stateful features for inbound connections
#        Always using state will allow the firewall to reject invalid
#        packets sent to otherwise open TCP services, e.g. XMAS, NULL
#        and SIN/FYN scans. The downside to choosing this behavior is that
#        services may become unreachable if the packet filter's state
#        table becomes full.
IP_ALWAYS_USE_STATE="N"                # default, ensures services remain available
#IP_ALWAYS_USE_STATE="Y"        # disallow invalid packets