ipfw and access-list

[adrian kok]

Dear all

I am using freebsd as router and firewall

I have question about the following rules 
implemented on ipfw and access-list of zebra

Do I have any problem and slow down the router using
same rule?

Thank you so much

# Deny all inbound traffic from non-routable reserved
address spaces
$cmd 00300 deny all from 192.168.0.0/16 to any in via
$pif  #RFC 1918 private IP
$cmd 00301 deny all from 172.16.0.0/12 to anyin via
$pif     #RFC 1918 private IP
$cmd 00302 deny all from 10.0.0.0/8 to anyin via $pif 
        #RFC 1918 private IP
$cmd 00303 deny all from 127.0.0.0/8 to anyin via $pif
       #loopback
$cmd 00304 deny all from 0.0.0.0/8 to anyin via $pif  
         #loopback
$cmd 00305 deny all from 169.254.0.0/16 to anyin via
$pif   #DHCP auto-config
$cmd 00306 deny all from 192.0.2.0/24 to anyin via
$pif       #reserved for doc's
$cmd 00307 deny all from 204.152.64.0/23 to anyin via
$pif  #Sun cluster interconnect
$cmd 00308 deny all from 224.0.0.0/3 to anyin via $pif
        #Class D & E multicast