#4 packets with wrong source address

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nobody
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5
2003-07-03
2003-07-03
Anonymous
No

I have set up the cipe vpn from a win2k box to a linux
box and it runs qutie well. (except I have to start the
dwk heavy industry service twice at OS startup).

The vpn addresses are 10.10.10.50 (win2k) and
10.10.10.39 (linux).

When I run a program on win2k which binds to
0.0.0.0:6112 and send udp broadcast packets to
255.255.255.255:6112, something goes wrong
and the linux box sees udp packets coming from a
wrong source destion (the ip of another interface
on the win2k box).
Here's the output of tcpdump:

# tcpdump -i cipcb1 udp and port 6112
Kernel filter, protocol ALL, datagram packet socket
tcpdump: listening on cipcb1
21:30:22.490140 192.168.5.1.6112 > 10.10.10.39.6112: udp 16
21:30:27.497685 192.168.5.1.6112 > 10.10.10.39.6112: udp 16

After I disable this interface (192.168.5.1) on win2k,
the packets' source address changes to the
address of yet another interface on win2k:

# tcpdump -i cipcb1 udp and port 6112
Kernel filter, protocol ALL, datagram packet socket
tcpdump: listening on cipcb1
21:40:42.653805 202.116.115.50.6112 > 10.10.10.39.6112:
udp 16
21:40:47.652717 202.116.115.50.6112 > 10.10.10.39.6112:
udp 16
21:40:52.659672 202.116.115.50.6112 > 10.10.10.39.6112:
udp 16

It seems to me that the driver fail to do the right thing
when processing the packets, but I don't have enough
knowledge and time to read the source code to locate
the (possible) bug.

Any comments?

Regards,

Yong

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