Re: [Madwifi-devel] how madwifi support more than 4 VAPs

[Xiangyong C. <cc...@ms...>]

Hello,
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Exactly, the question is "why madwifi can not support more than 4 WEP VAPs?=
". Haha.. I found the reason.
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First step, we see a simple example on madwifi-ng-r2628-20070801 without an=
y modification in source code.
I create 2 WEP VAP.
ath0 shared-auth key[1]:0000000000
ath1 open-auth key[1]:1111111111
Everyone can connect ath1 correctly.=20
But guess how sta can connect ath0? The correct answer is shared-auth key[1=
]:1111111111
Yes, the point is that, every key position(1 to 4) will only save the last =
key set in the same position(1 to 4), not care it is belong to another VAP.=
 And the auth-mode saved is right.
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Then, let's see 8 WEP VAPs I asked before.
Change ATH_BCBUF from 4 to 8 in if_athvar.h , so we can create 8 VAPs. The =
step is right.
Now create them as below,
ath0 shared key[1]:0000000000
ath1 shared key[2]:1111111111
ath2 shared key[3]:2222222222
ath3 shared key[4]:3333333333
ath4 open key[1]:4444444444
ath5 open key[2]:5555555555
ath6 open key[3]:6666666666
ath7 open key[4]:7777777777
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The correct way to connect them is,
ath0 shared key[1]:4444444444
ath1 shared key[2]:5555555555
ath2 shared key[3]:6666666666
ath3 shared key[4]:7777777777
ath4 open key[1]:4444444444
ath5 open key[2]:5555555555
ath6 open key[3]:6666666666
ath7 open key[4]:7777777777
And sta can ping to each VAP. This way is OK.
Note: DO NOT connect ath0 to ath3 with wrong key, if do so, you can not con=
nect to any of them until wifi0 recreate. This is another question, which I=
 guess was raised by ni pointer fault in this mode.
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Now, let's discuss why and how.
Why madwifi can not support more than 4 WEP VAPs?
Because madwifi save WEP key in only 4 global key-slot. And the key-index p=
osition(1 to 4) to VAP is same to device.
Different VAP should not save WEP key in same position, or it will be repla=
ced by the latest WEP key in the same position.
Specially, for more than 4 WEP VAPs, only 4 global key-slot position, there=
 must be 2 VAP in same position.
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How can madwifi support more more than 4 WEP VAPs?
The point is global key-slot assignment. 128 key-slot may be used more effe=
ctive in WEP mode, not only the first 4 position.
I hope to get the patch or answer. Also I would try if HAL support it.
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Best Wishes,
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Shawn Chen
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