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Re: IP Filter does not seem to work correctly with bge(4) when hardware checksums are enabled

On Wed, Jan 28, 2009 at 12:30:01AM -0500, Greg A. Woods wrote:
> I think there's a similar problem to PR#34799 still happening with
> bge(4) in netbsd-4 on an HP Proliant box I'm setting up as a NAT and
> firewall.
> I.e. ipmon is reporting "bad" packets blocked even though the "pass"
> rule they match is triggered.  (too bad "bad" isn't well documented!)
> ifconifg:

Last time this was reported, I think the culprit was the hardware
checksumming, which ensures that the packets are correct *on the
wire*, but not yet in the machine's main memory. As I understand,
this would apply to transmitted packets only, but on a NAT box or
a router, most packets are transmitted at some point...

Switch .*SUM.* off for a quick test.


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