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From: "Khoa A. To" <takhoa@rice.edu>
To: "FreeBSD_Net" <freebsd-net@FreeBSD.ORG>
Date: Fri, 29 Aug 2003 11:17:16 -0500
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Subject: Reversed MAC lookup inside FreeBSD kernel?
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Hi,

I'm new to kernel code, and don't understand the structure of ARP table very
well.  Could someone please point me to the right direction for the
following problem I have:

I need to get a translation of MAC addresses to IP addresses in the kernel.
I saw some postings about how to translate MAC to IP in the user level, but
they seem to require the host to send a packet to that MAC address and some
other ways that also require the host to actually send some request packets
out.  All my MAC-IP addresses are already set statically using "arp -s" in
the ARP table.  When I'm in the kernel, how do I get a hold of the ARP table
and do some kind of reversed search to get the IP address out?

Thank you very much,
Khoa.