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Date: Sun, 18 Sep 2005 18:47:42 -0400
From: Chuck Swiger <cswiger@mac.com>
Organization: The Courts of Chaos
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To: Milscvaer <millueradfa@yahoo.com>
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Cc: freebsd-net@freebsd.org
Subject: Re: UDP dont fragment bit
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Milscvaer wrote:
> FreeBSD ought to add per-socket socket options to
> allow a programmer to turn  on and off the don't
> fragment bit for UDP and the UDP checksum, on a per
> socket basis.

Sounds like a fine suggestion.

> FreeBSD needs to implement this feature. We requested
> this same feature years ago and I cannot believe such
> a simple, basic feature is still not implemented, or
> not documented in the setsockopt manpage anyhow. This
> needs to be implemented. We need it. Trust me.

Have you submitted a PR?  Are you willing to work on it yourself?

In the meantime, you can use libnet in advanced mode to create arbitrary UDP 
packets, altering any values you want including the checksum.  Make sure you 
disable your NIC's hardware checksum capabilities, if it has them.

-- 
-Chuck