Limiting ICMP echo replies when creating a PING program

Question

I was writing a multithreaded ping program. I created rawsockets on each thread (for each IP) and sent ICMP Echo Request to each using sendto() and then I did recvfrom() in each thread. I am getting messages from IPs in various sockets(like if I had used socket S1 for sendto for IP1, I get echo-replies from IP1 to S1, S2 etc). Do I need to do a bind?

Also another problem is that even though I send only 1 ICMP request I get back many echo replies from target. Is there any way I can limit this? This is causing me to miss some of the other ICMP packets. Is there a way for my program to ask the target to stop sending ICMP echo's?

Thanks,

Answer 1

Raw sockets pick up all incoming packets; you will need to do your own filtering, or - better yet - only open one raw socket, and detect all of the incoming echo replies on a single thread.

Your duplicate packets may be because of the multiple raw sockets - you'll get one copy of each incoming packet per socket. Also note that in some cases internet packets can be duplicated (this is rare, however).