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Hi!

I'm writing a nw card driver for my OS.
I've stuck at a programming problem, and don't have
a consistent test to check my modifications.
Could you tell me a simple way to send raw
packets from a host process to guest QEMU VM?
Nw hw is an e1000 or something similar, standard card.
Thanks in advance

Robert wrote:Could you tell me a simple way to send raw packets

I don't think that's possible. Not in a simple way anyway. Try using simple one packet protocols instead, like ICMP or UDP. Check out "ping", "mtr" and "nc -u" (netcat).
Otherwise tcpdump can save pcap files, and there's a way to replay a pcap with bit-twist or tcpreplay. So if you manually create a pcap file with a hex editor, you can send raw packets, but that's not simple nor easy to do at all.

Cheers,
bzt

Robert wrote:Hi!

I'm writing a nw card driver for my OS.
I've stuck at a programming problem, and don't have
a consistent test to check my modifications.
Could you tell me a simple way to send raw
packets from a host process to guest QEMU VM?
Nw hw is an e1000 or something similar, standard card.
Thanks in advance

It should be possible to write a script or program to send raw pocket from the host. Probably can't be too malformed though like not having IP headers, etc. You aren't trying to reinvent a different networking standard from that level up right? Standard NICs are unlikely to accept pockets without IP headers either so that either ways won't work.

Then, you can probably find some inspirations from viewtopic.php?f=1&t=39828 about how to get the pockets into Qemu.

Good luck!

So if I'd like to create a tap device to connect VM's nw interface and my package sender python script, how should I do it (it doesn't work for me now)

my idea:
sudo /etc/qemu-ifup tapdev
qemu ... -net tap,ifname=tapdev,script=0,downscript=no
And open /dev/tapdev as a binary file