Kernel Headers and patched wireless drivers

monkeypants · 2014-12-21 10:14:13

I'm trying to enable packet injection on my Acer C720 Chromebook.

A guide I'm following suggests I need to download linux headers a la 'linux-headers-$(uname -r)'. Pacman cannot find the package, I managed to find this but I am unsure how to install it, or if I even need it.

'pacman -Ss kernel' shows that I have these installed

core/iptables 1.4.21-1 [installed]
    Linux kernel packet control tool
core/kmod 19-1 [installed]
    Linux kernel module handling
core/linux 3.17.6-1 (base) [installed]
    The Linux kernel and modules
core/linux-api-headers 3.16.2-1 [installed]
    Kernel headers sanitized for use in userspace

The wifi card is Atheros AR9462 with the ath9k driver as evidenced by 'lspci -k'. I've read that ath9k driver is supplied with newer versions of linux kernel, which is why it worked out of the box, so do I actually need to update or install a new driver?

A guide I've been reading suggests I use the Compat-Wireless driver. Is this what is now backports? The guide also points to some patches, but I imagine these are out of date since they are targeted at the Compat driver. One of the patches is to fix the -1 channel, but I do not suffer from this problem.

So it appears that my drivers are up to date, but I cannot get any positive results from 'aireplay-ng mon0 --test'. I have tried it at multiple access points that I own and know are functioning correctly. I have also tried without launching a monitor and using wlp1s0 interface directly.

Is there actually a patch I need, or am I just out of luck with this card?

monkeypants · 2014-12-21 11:32:13

I found this guide. No idea how I missed that since I have used the FAQ before, must have skipped over the google result too, whoops.

graysky · 2014-12-21 12:02:38

On Arch, the kernel headers are in [core] and are called linux-headers. Did you search the AUR for the package you want?

monkeypants · 2014-12-21 12:20:32

graysky wrote:

On Arch, the kernel headers are in [core] and are called linux-headers. Did you search the AUR for the package you want?

Thanks for that, I have the headers installed. I'm not sure what I'm looking for, everything I'm reading indicates that my card should support packet injection, and yet it doesn't seem to work.

Should I acquire the ath9k driverbackports driver, patch it and re-install?

Last edited by monkeypants (2014-12-21 12:29:36)

graysky · 2014-12-21 12:39:34

monkeypants wrote:

Thanks for that, I have the headers installed. I'm not sure what I'm looking for, everything I'm reading indicates that my card should support packet injection, and yet it doesn't seem to work.
Should I acquire the ath9k driverbackports driver, patch it and re-install?

1. You only need the headers if you seek to build a custom kernel module.
2. This module is indeed supplied with the kernel so you shouldn't need to build it:

% find /lib/modules -name 'ath9k.ko*'
/lib/modules/3.17.6-1-ARCH/kernel/drivers/net/wireless/ath/ath9k/ath9k.ko.gz

EDIT: OK... I think I understand now, packet injection is something that the out-of-the-box module doesn't do, yes? You wish to build it with this enabled?

Last edited by graysky (2014-12-21 12:40:27)

graysky · 2014-12-21 12:44:16

BTW, the patch you're referencing is ancient:

your patch wrote:

linux-source-2.6.17-orig/net/ieee80211/ieee80211_tx.c

That version of the kernel is from June of 2006. If I look in the source tree (3.17.6) for that file:

% find -type f -name ieee80211_tx.c
./drivers/staging/rtl8192u/ieee80211/ieee80211_tx.c

Last edited by graysky (2014-12-21 12:44:28)

monkeypants · 2014-12-21 13:03:54

Ah Yes I see now that it's very old, probably why the patch failed (I was trying dry-run).

packet injection is something that the out-of-the-box module doesn't do, yes? You wish to build it with this enabled?

Correct, maybe. I do wish to enable packet injection, but as far as I can tell it should already be enabled since I cannot find any patches or guides for enabling it on ath9k.

The aircrack website points me to madwifi, but madwifi is depreciated and replaced with ath5k and ath9k, which I already have.

graysky · 2014-12-21 13:12:14

Dunno how to do it, but if that patch doesn't apply to something you can compile. You will need to modify it to work or find one that does work with a modern kernel.

monkeypants · 2015-01-06 16:57:47

My problem is still ultimately unresolved, but I do not believe driver patching to be the culprit. The discussion has crossed over to the aircrack forums. If a solution arises I will also post it here and mark the thread as resolved.

Arch Linux

#1 2014-12-21 10:14:13

Kernel Headers and patched wireless drivers

#2 2014-12-21 11:32:13

Re: Kernel Headers and patched wireless drivers

#3 2014-12-21 12:02:38

Re: Kernel Headers and patched wireless drivers

#4 2014-12-21 12:20:32

Re: Kernel Headers and patched wireless drivers

#5 2014-12-21 12:39:34

Re: Kernel Headers and patched wireless drivers

#6 2014-12-21 12:44:16

Re: Kernel Headers and patched wireless drivers

#7 2014-12-21 13:03:54

Re: Kernel Headers and patched wireless drivers

#8 2014-12-21 13:12:14

Re: Kernel Headers and patched wireless drivers

#9 2015-01-06 16:57:47

Re: Kernel Headers and patched wireless drivers

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