ipfw denial log - what's this mean?

[Rob]

Hi Everyone,

My 6.2-Release system coughed up a report of denied packets from ipfw in its daily security run:

ipfw denied packets:
+++ /tmp/security.gnkQg5CA	Thu Apr 10 03:04:15 2008
+00200        12         795 deny ip from any to 127.0.0.0/8

What does this mean?  I understand that's the loopback interface, but I'm not terribly knowledgeable on ipfw.  Is this some crack attempt, or normal background noise?  I don't understand how lo0 would ever see any IP addresses other than its own?!

The whole rule set looks like this:

# ipfw show
00100   4749394  1011660210 allow ip from any to any via lo0
00200        12         795 deny ip from any to 127.0.0.0/8
00300         0           0 deny ip from 127.0.0.0/8 to any
01005  17272713  2535346056 fwd 12.219.128.1 tcp from 12.219.128.39 to any out
65000 174044808 81045388703 allow ip from any to any
65535         1         328 deny ip from any to any

  -Thanks, Rob