# ip_reass() api and fragmentation



## choupani (Sep 22, 2010)

Hi all,
I'm developing a Firewall+NAT system by pfil hooking.
My question is about reassembling packets that are received in DIR_IN, because I need to 
collect all data of frag packets to calculate checksum after changing IP/Ports,
as far as you know.
I can use ip_reass() function and this is working truly, but my problem is raised when after changing IP/Port for NAT and calc checksum, I need to send original packets (packets that have been received before reassemble), because these packets maybe have fragmented by clients as ICMP Frag Needed packet.


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