Hi all,

I am programming in Kernel-space using Netfilter hooks to filter packets from a specific aplication (UDP packets) and i want to make a lookup to the routing table to see if there is a route to this pakets.
My problem is with the fib_lookup funtion that crashs all the system every time i try to use it.
I want to know if anyone knows how to make a lookup to the routing table in Kernel-space?

fib_lookup(struct net *net, const struct flowi4 *flp,struct fib_result *res)

Any tips will help me a lot!!

Thanks in advance!!

Dear ,
You must be use below commands and sniffers to trace for issue.

1. route -n

2. netstat -aun and netstat -ra

3. tcpdum and wireshark to capture udp packets.see below web link also.

http://www.rationallyparanoid.com/articles/tcpdump.html

Regards,
Rahul Kumar

Thanks for the answer but i resolved the problem by calling the fiblookup function out of the hook interruption. I assume that this function cannot be called from an interruption but there is no literature that says that (at least i dint found none yet).

cheers

HI,I have same issue.Can you show me the code of fib_lookup part or full code ? Thank you....

You're replying to a 5 year old thread, where the OP is long gone. Best to start your own thread, and reference this one if need be.