嘻嘻哈哈的部落格(blog)

在文件/etc/rc.conf中设定：

ipfilter_enable=”YES”
ipfilter_rules=”/etc/ipf.rules”
ipmon_enable=”YES” # optional
ipmon_flags=”-Ds” # optional

bash-2.05b# cat /etc/ipf.rules
#######################################################
# No restrictions on Inside LAN Interface for private network
# Not needed unless you have LAN
#######################################################

#pass out quick on xl0 all
#pass in quick on xl0 all

#######################################################
# No restrictions on Loopback Interface
#######################################################
pass in quick on lo0 all
pass out quick on lo0 all

#######################################################
# Interface facing Public Internet (Outbound Section)
# Interrogate session start requests originating from behind the
# firewall on the private network
# or from this gateway server destine for the public Internet.
#######################################################

# Allow out access to my ISP’s Domain name server.
# xxx must be the IP address of your ISP’s DNS.
# Dup these lines if your ISP has more than one DNS server
# Get the IP addresses from /etc/resolv.conf file
pass out quick on xl0 proto tcp from any to xxx port = 53 flags S keep state
pass out quick on xl0 proto udp from any to xxx port = 53 keep state

# Allow out access to my ISP’s DHCP server for cable or DSL networks.
# This rule is not needed for ‘user ppp’ type connection to the
# public Internet, so you can delete this whole group.
# Use the following rule and check log for IP address.
# Then put IP address in commented out rule & delete first rule
pass out log quick on xl0 proto udp from any to any port = 67 keep state
#pass out quick on xl0 proto udp from any to z.z.z.z port = 67 keep state

# Allow out non-secure standard www function
pass out quick on xl0 proto tcp from any to any port = 80 flags S keep state

# Allow out secure www function https over TLS SSL
pass out quick on xl0 proto tcp from any to any port = 443 flags S keep state

# Allow out send & get email function
pass out quick on xl0 proto tcp from any to any port = 110 flags S keep state
pass out quick on xl0 proto tcp from any to any port = 25 flags S keep state

# Allow out Time
pass out quick on xl0 proto tcp from any to any port = 37 flags S keep state

# Allow out nntp news
pass out quick on xl0 proto tcp from any to any port = 119 flags S keep state

# Allow out gateway & LAN users non-secure FTP ( both passive & active modes)
# This function uses the IPNAT built in FTP proxy function coded in
# the nat rules file to make this single rule function correctly.
# If you want to use the pkg_add command to install application packages
# on your gateway system you need this rule.
pass out quick on xl0 proto tcp from any to any port = 21 flags S keep state

# Allow out secure FTP, Telnet, and SCP
# This function is using SSH (secure shell)
pass out quick on xl0 proto tcp from any to any port = 22 flags S keep state

# Allow out non-secure Telnet
pass out quick on xl0 proto tcp from any to any port = 23 flags S keep state

# Allow out FBSD CVSUP function
pass out quick on xl0 proto tcp from any to any port = 5999 flags S keep state

# Allow out ping to public Internet
pass out quick on xl0 proto icmp from any to any icmp-type 8 keep state

# Allow out whois for LAN PC to public Internet
pass out quick on xl0 proto tcp from any to any port = 43 flags S keep state

# Block and log only the first occurrence of everything
# else that’s trying to get out.
# This rule enforces the block all by default logic.
block out log first quick on xl0 all

#######################################################
# Interface facing Public Internet (Inbound Section)
# Interrogate packets originating from the public Internet
# destine for this gateway server or the private network.
#######################################################

# Block all inbound traffic from non-routable or reserved address spaces
block in quick on xl0 from 192.168.0.0/16 to any #RFC 1918 private IP
block in quick on xl0 from 172.16.0.0/12 to any #RFC 1918 private IP
block in quick on xl0 from 10.0.0.0/8 to any #RFC 1918 private IP
block in quick on xl0 from 127.0.0.0/8 to any #loopback
block in quick on xl0 from 0.0.0.0/8 to any #loopback
block in quick on xl0 from 169.254.0.0/16 to any #DHCP auto-config
block in quick on xl0 from 192.0.2.0/24 to any #reserved for docs
block in quick on xl0 from 204.152.64.0/23 to any #Sun cluster interconnect
block in quick on xl0 from 224.0.0.0/3 to any #Class D & E multicast

##### Block a bunch of different nasty things. ############
# That I do not want to see in the log

# Block frags
block in quick on xl0 all with frags

# Block short tcp packets
block in quick on xl0 proto tcp all with short

# block source routed packets
block in quick on xl0 all with opt lsrr
block in quick on xl0 all with opt ssrr

# Block nmap OS fingerprint attempts
# Log first occurrence of these so I can get their IP address
block in log first quick on xl0 proto tcp from any to any flags FUP

# Block anything with special options
block in quick on xl0 all with ipopts

# Block public pings
block in quick on xl0 proto icmp all icmp-type 8

# Block ident
block in quick on xl0 proto tcp from any to any port = 113

# Block all Netbios service. 137=name, 138=datagram, 139=session
# Netbios is MS/Windows sharing services.
# Block MS/Windows hosts2 name server requests 81
block in log first quick on xl0 proto tcp/udp from any to any port = 137
block in log first quick on xl0 proto tcp/udp from any to any port = 138
block in log first quick on xl0 proto tcp/udp from any to any port = 139
block in log first quick on xl0 proto tcp/udp from any to any port = 81

# Allow traffic in from ISP’s DHCP server. This rule must contain
# the IP address of your ISP’s DHCP server as it’s the only
# authorized source to send this packet type. Only necessary for
# cable or DSL configurations. This rule is not needed for
# ‘user ppp’ type connection to the public Internet.
# This is the same IP address you captured and
# used in the outbound section.
pass in quick on xl0 proto udp from z.z.z.z to any port = 68 keep state

# Allow in standard www function because I have apache server
pass in quick on xl0 proto tcp from any to any port = 80 flags S keep state

# Allow in non-secure Telnet session from public Internet
# labeled non-secure because ID/PW passed over public Internet as clear text.
# Delete this sample group if you do not have telnet server enabled.
#pass in quick on xl0 proto tcp from any to any port = 23 flags S keep state

# Allow in secure FTP, Telnet, and SCP from public Internet
# This function is using SSH (secure shell)
pass in quick on xl0 proto tcp from any to any port = 22 flags S keep state

# Block and log only first occurrence of all remaining traffic
# coming into the firewall. The logging of only the first
# occurrence stops a .denial of service. attack targeted
# at filling up your log file space.
# This rule enforces the block all by default logic.
block in log first quick on xl0 all
################### End of rules file ###########################

这是一个网上找的比较完善的ipf防火墙脚本范本

实际应用还得做一些小小的改动

比如网卡的设备号

防火墙的策略什么的

Tags: FreeBSD, Security //