Sending ARP request to unicast MAC instead of broadcast MAC address?
sking at kingrst.com
Fri Jun 18 02:14:45 UTC 2010
I believe they call this a Gratuitous ARP Request. It is used
automatically when interfaces are brought up to detect IP conflicts.
On 6/17/10 5:45 PM, Chris Woodfield wrote:
> Looks like all the replies I got were private, so thanks all - to summarize, I got everything from "Read The Fine Kernel Source" to "Read The Fine RFC" to "Read RFC 1122, Section 184.108.40.206, it's quite a Fine read".
> So for other folks out there like me who obviously can't read RFCs, the answer is "yes". :)
> On Jun 16, 2010, at 3:57 51PM, Chris Woodfield wrote:
>> OK, this sounds Really Wacky (or, Really Hacky if you're into puns) but there's a reason for it, I swear...
>> Will typical OSS UNIX kernels (Linux, BSD, MacOS X, etc) reply to a crafted ARP request that, instead of having FF:FF:FF:FF:FF:FF as its destination MAC address, is instead sent to the already-known unicast MAC address of the host?
>> Next, what would be your utility of choice for crafting such a packet? Or is this something one would need to code up by hand in a lower-level language?
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