Arkady
Sun May 29 02:55:51 CDT 2005
"Maxim S. Shatskih" <maxim@storagecraft.com> wrote in message
news:uSayg37YFHA.2572@TK2MSFTNGP14.phx.gbl...
> ???
> TCP/IP checksums do not include the MAC address,
Sure.
and Ethernet checksums are
> not visible to any software - they are internal for the NIC hardware.
>
Depends upon NIC , and can be ( if not in hardware ) in firmware or
in miniport
Arkady
> --
> Maxim Shatskih, Windows DDK MVP
> StorageCraft Corporation
> maxim@storagecraft.com
>
http://www.storagecraft.com
>
> "Arkady Frenkel" <arkadyf@hotmailxdotx.com> wrote in message
> news:u4EhbG1YFHA.1344@TK2MSFTNGP15.phx.gbl...
>> If you change MAC address as part of IEEE802.3 or Ethernet II frame that
>> exactly what Thomas wrote to you , you have to recalculate checksum of
>> all
>> the packet ( NDIS know nothing about that )
>> Arkady
>>
>> "Michal Filka" <michal.filka@atlas.cz> wrote in message
>> news:uM68rLpYFHA.3096@TK2MSFTNGP15.phx.gbl...
>> >> If you are talking about the Ethernet CRC at the tail of each frame,
>> >> then
>> >> that is taken care of entirely by the adapter hardware and is
>> >> invisible
>> >> to
>> >> NDIS.
>> > ... yes ... I want to change MAC address of incoming frame and re-send
>> > it.
>> >>
>> >> If you are talking about other checksums within a packet then the
>> >> answer
>> > is
>> >> different. If you change an Ethernet frame (by making a complete copy
>> >> and
>> >> modifying the copy), then you are responsible for modifying the packet
>> > (and
>> >> possibly OOB data) to have correct checksums.
>> > ... I do copy of whole packet except MAC address (see above), so as I
>> > understand to it I don't
>> > have to change any checksum ...do I ?
>> > ... in fact in present situation packet is created from HeaderBuffer &
>> > LookAheadBuffer (and so on) because underlying miniport uses
>> > old-fashion
>> > style of indication, so there should'nt be any OOB ...
>> >
>> >> Good luck,
>> > ... thank's I need it a lot ;-)
>> >
>> > Thank's for answer
>> > Michal
>> >
>> >
>>
>>
>
>