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#
# /etc/bastille-firewall.cfg
#
# Configuration fiel for both 2.2/ipchains and 2.4/netfilter scripts
#
# version 0.99-beta1
# 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. 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=""
# 1) define your interfaces
# 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+" # SAFEST
INTERNAL_IFACES="" # SAFEST
# 2) services for which we want to log access attempts to syslog
# 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=""
UDP_AUDIT_SERVICES=""
ICMP_AUDIT_TYPES=""
# 3) services we allow connections to
#
# 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="109 53 143 80 20 21 22 110 443 25" # MINIMAL/SAFEST
TCP_PUBLIC_SERVICES="" # MINIMAL/SAFEST
UDP_PUBLIC_SERVICES="" # MINIMAL/SAFEST
TCP_INTERNAL_SERVICES="www ssh" # MINIMAL/SAFEST
UDP_INTERNAL_SERVICES="" # MINIMAL/SAFEST
# 4) 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="N" # SAFEST
# 5) Services to explicitly block. 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"
# 6) Source Address Verification helps prevent "IP Spoofing" attacks
#
ENABLE_SRC_ADDR_VERIFY="Y" # SAFEST
# 7) IP Masquerading / NAT. 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="192.168.4.0/24" # DISABLE/SAFEST
IP_MASQ_MODULES="" # RECOMMENDED
# 8) How to react to disallowed packets
# whether to "REJECT" or "DENY" disallowed packets; if you're running any
# public services, you probably ought to use "REJECT"; if in serious stealth
# mode, choose "DENY" so simple probes don't know if there's anything out there
# NOTE: disallowed ICMP packets are discarded with "DENY", as
# it would not make sense to "reject" the packet if you're
# trying to disallow ping/traceroute
#
REJECT_METHOD="DENY"
# 9) DHCP
# 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) 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. 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
# 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
# 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
# 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
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