Ipfw config

From: Nick Twaddell (nick_at_webspacesolutions.com)
Date: 07/28/04

  • Next message: Nigel Houghton: "Re: Ipfw config" 
    To: <freebsd-security@freebsd.org>
Date: Wed, 28 Jul 2004 12:38:56 -0700

    That last email got a little garbled, I forgot to take it off of html :)

    add 100 allow all from any to any via lo0
    add 110 deny log all from any to 127.0.0.0/8
    add 120 deny log ip from 127.0.0.0/8 to any

    add 00200 check-state

    add 00250 deny all from any to any frag in via bge0

    add 00260 deny tcp from any to any established in via bge0

    ###### outbound section ######
    ## standard http ##
    add 00300 allow tcp from any to any 80 out via bge0 setup keep-state
    ## secure https ##
    add 00301 allow tcp from any to any 443 out via bge0 setup keep-state
    ## dns ##
    add 00310 allow tcp from any to any 53 out via bge0 setup keep-state
    add 00311 allow udp from any to any 53 out via bge0 keep-state
    ## pop & smtp ##
    add 00330 allow tcp from any to any 25 out via bge0 setup keep-state
    add 00331 allow tcp from any to any 110 out via bge0 setup keep-state
    ## give root all ##
    add 00340 allow tcp from me to any out via bge0 setup uid root keep-state
    ## ftp with passive ports ##
    add 00375 allow tcp from me to any 21 out via bge0 setup keep-state
    add 00376 allow tcp from me to any 49152-65535 out via bge0 setup keep-state
    ## ssh ##
    add 00380 allow tcp from any to any 22 out via bge0 setup keep-state
    ## ntp ##
    add 00390 allow tcp from any to any 123 out via bge0 setup keep-state
    add 00391 allow udp from any to any 123 out via bge0 keep-state
    ## ident ##
    add 00400 allow tcp from any to any 113 out via bge0 setup keep-state
    add 00401 allow udp from any to any 113 out via bge0 keep-state
    ## whois ##
    add 00410 allow tcp from any to any 43 out via bge0 setup keep-state
    ## snmp ##
    add 00420 allow udp from any to any 161 out via bge0 keep-state
    ## finger ##
    add 00430 allow tcp from any to any 79 out via bge0 setup keep-state
    add 00431 allow udp from any to any 79 out via bge0 keep-state

    ###### inbound section #######
    ## standard http ##
    add 00600 allow tcp from any to any 80 in via bge0 setup keep-state
    ## secure https ##
    add 00601 allow tcp from any to any 443 in via bge0 setup keep-state
    ## dns ##
    add 00611 allow udp from any to me 53 in via bge0 keep-state
    add 00612 allow tcp from any to me dst-port 53 in via bge0 setup keep-state
    ## pop & smtp ##
    add 00630 allow tcp from any to me 25 in via bge0 setup keep-state
    add 00631 allow tcp from any to me 110 in via bge0 setup keep-state
    ## imap ##
    add 00635 allow tcp from any to me 143 in via bge0 setup keep-state
    ## ftp ##
    add 00640 allow tcp from any to me 21 in via bge0 setup keep-state
    add 00641 allow tcp from any to me 49152-65535 in via bge0 setup keep-state
    #add 00641 allow tcp from any 20 to any 1024-49151 out via bge0 setup
    keep-state
    ## ssh ##
    add 00660 allow tcp from any to me 22 in via bge0 setup keep-state
    ## snmp ##
    add 00690 allow udp from any to me 161 in via bge0 keep-state
    ## razor ##
    add 00695 allow tcp from me to any dst-port 2703 out via bge0 setup
    keep-state

    ###### ICMP ######
    ## Allow out & in console traceroot command ##
    add 00700 allow udp from me to any 33435-33500 out via bge0 keep-state
    add 00701 allow log icmp from any to me icmptype 3,11 in via bge0 limit
    src-addr 2
    ## ping out ##
    add 00710 allow icmp from any to any out via bge0 keep-state
    ## ping in ##
    add 00720 allow log icmp from any to me icmptype 0,8 in via bge0
    ## This sends a RESET to all ident packets ##
    add 00730 reset log tcp from any to me 113 in via bge0 limit src-addr 4
    ## Stop & log external redirect requests ##
    add 00740 deny log icmp from any to any icmptype 5 in via bge0
    ## Stop & log spoofing Attack attempts ##
    add 00750 deny log ip from me to me in via bge0
    ## Stop & log ping echo attacks ##
    add 00760 deny log icmp from any to me icmptype 0,8 in via bge0

    ###### Everything Else #####
    ## Reject & Log all setup of tcp incoming connections from the outside ##
    add 00770 deny log tcp from any to any setup in via bge0
    ## Reject all port 80 http packets that fall through to here ##
    add 00780 deny tcp from any to any 80 out via bge0
    ## Everything else is denied by default ##
    add 00790 deny log logamount 500 all from any to any

    This should work

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  • Next message: Nigel Houghton: "Re: Ipfw config"

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