Rtl8812au: Use fixed mac address when one is not specified

Created on 13 Dec 2017 · 9Comments · Source: aircrack-ng/rtl8812au

Leaving a commit here for later savings.
The code will use a fixed mac address when one is not specified.

Would people be interested in this? pros vs cons?

https://github.com/goncalossilva/rtl8812AU/commit/eaa89bf90cf30a1e6ed4e828417d52f4e9b97a9d

Thanks.

Source

kimocoder

All 9 comments

In my opinion, when pentesting, the random address is good. However, when using the dongle for normal usage in an ARP spoofing protected network or MAC filtering AP, it is bad.

samiux on 14 Dec 2017

I don't think a driver should take care of changing the mac address randomly. There are tools for that like macchanger. We shouldn't implement stuff that is not expected to be part of a driver. This will ultimately confuse people.

evilphish on 14 Dec 2017

👍1

Drivers should never change MAC and should always use the MAC of the adapter. Tools don't need to change the MAC at all, it is in the packets (and packets can be crafted).

If MAC changing is necessary, it just need to be ensured that the drivers plays nice when the MAC is changed via MACChanger.

Mister-X- on 14 Dec 2017

👍1

I totally agree that MAC should be fixed to the set (standard) one, but by default the driver actually is set to use random MAC as seen on the screenshot.. so it looks like we'd agree om turning the 'stupid' feature off in the next commits pushed then. Thanks for feedback on the matter!

img_20171214_231254

kimocoder on 14 Dec 2017

I reported the MAC address randomization to Kali Linux and they said that MAC address randomization is a new feature of Network Manager. It is not a bug.

I did some Google search and found out that there is a way to disable this feature.

The current driver is working great on Ubuntu Gnome 16.04.3 HWE. I think that we better do not alter the driver for this matter.

samiux on 15 Dec 2017

For Ubuntu 17.04 (or later) and Kali Linux 2017.3 (or later) as well as NetworkManager 1.2.0 (or later) add the following lines

[device]
wifi.scan-rand-mac-address=no

at the end of file /etc/NetworkManager/NetworkManager.conf and restart NetworkManager with the command:

sudo systemctl restart NetworkManager

samiux on 15 Dec 2017

👍1

This is current output of macchanger, and it switches MAC when unplugged/plugged.
I say we set it fixed (at least in the driver) as @Mister-X- and @evilphish mentions, the driver should not take care of MAC switching. I'll push the commit with fixed MAC. thanks for input/feedback.

Update: have tested it and as it is currently, the driver sets a random MAC, then the NetworkManager puts a random MAC afterwards, so it doesn't help setting "wifi.scan-rand-mac-address" anyway. After disabling the feature in the driver, it's also possible to set fixed/random in NetworkManager as README.md suggests.

root@kali:~/# macchanger -s wlan1
Current MAC: 46:7a:15:ce:70:88 (unknown)
Permanent MAC: 00:c0:ca:95:4c:c6 (ALFA, INC.)

kimocoder on 16 Dec 2017

The commit along with few others will be pushed soon.
Random MAC may/should be set in NetworkManager, or with "macchanger" instead of the driver.
Closed.

kimocoder on 16 Dec 2017

It seems MAC address randomization was only removed in version v5.1.5. After that randomization was seemingly re-introduced, or am I missing something?

https://github.com/aircrack-ng/rtl8812au/blob/v4.3.21/core/rtw_ieee80211.c#L1490

https://github.com/aircrack-ng/rtl8812au/blob/v5.1.5/core/rtw_ieee80211.c#L1382

https://github.com/aircrack-ng/rtl8812au/blob/v5.2.9/core/rtw_ieee80211.c#L1382