Hi, all

I use IP filter v4.1.9(592) on Solaris 10 U8. 

During testing, I observe that IPFilter will block the fragmented
packets out of order when the server doesn't receive the first segment
before any of others. 

Snoop packets are given as an example as the following: Packet 1 & 3 are
dropped. Packet 2 & 4 are passed, but waiting for the later fragment. As
a result of the packets dropping, ICMP of reassembly time exceeded
packets are sent out finally.

  1   0.00000 47.154.158.103 -> zcydsf874ha  UDP IP fragment ID=10796
Offset=1480 MF=0 TOS=0x0 TTL=64
  2   0.00025 47.154.158.103 -> zcydsf874ha  UDP IP fragment ID=10796
Offset=0    MF=1 TOS=0x0 TTL=64
  3  10.00706 47.154.158.103 -> zcydsf874ha  UDP IP fragment ID=10797
Offset=1480 MF=0 TOS=0x0 TTL=64
  4   0.00010 47.154.158.103 -> zcydsf874ha  UDP IP fragment ID=10797
Offset=0    MF=1 TOS=0x0 TTL=64
  5   6.89527  zcydsf874ha -> 47.154.158.103 ICMP Time exceeded (in
reassembly)
  6   0.00010  zcydsf874ha -> 47.154.158.103 ICMP Time exceeded (in
reassembly)
  7   0.00008  zcydsf874ha -> 47.154.158.103 ICMP Time exceeded (in
reassembly)


I come to consult if IPFilter later version supports automatically
reassemble IP fragments, or any solution can help me to resolve such
problem?

thank you very much!

P.S. 

current IP filter version:

bash-3.00# ipf -V
ipf: IP Filter: v4.1.9 (592)
Kernel: IP Filter: v4.1.9
Running: yes
Log Flags: 0 = none set
Default: pass all, Logging: available
Active list: 1
Feature mask: 0x107


Best regards 

Xiaohong Liu (Susan) 
Email: [email protected] 
Tele:  +65 6510 7931/ESN 542 7931 

"The author works for Telfonaktiebolaget L M Ericsson ("Ericsson"), who
is solely responsible for this email and its contents. All inquiries
regarding this email should be addressed to Ericsson. Nortel has
provided the use of the nortel.com domain to Ericsson in connection with
this email solely for the purpose of connectivity and Nortel Networks
has no liability for the email or its contents. The web site for
Ericsson is www.ericsson.com <http://www.ericsson.com/> ."


 

<<Blank Bkgrd.gif>>

Reply via email to