How to Set Your Wi-FI Card Tx Power Higher Than 30dbm
Hello to the Community!
This is a small how-to for Kali users taken from here:
http://null-byte.wonderhowto.com/how...0-dbm-0149606/
The only difference from the original article is that I'm using the latest wireless-regdb dated 13-Jun-2014
Quote:
Do you have an Alfa AWUS036NH Wi-Fi adapter that claims it can go to 2000 mWs, or some card that can supposedly transmit power over 1000 mW? If so, you may have run into problems setting your card's TXPOWER higher than 30 dBm, which is about 1000 mW. Well, I will show you how to break that barrier and go as high as you want!
So, here we go. Download all necessary programs that we need and extract them:
Code:
apt-get update
apt-get install python-m2crypto libgcrypt11 libgcrypt11-dev libnl-dev
cd /root/
wget http://wireless.kernel.org/download/crda/crda-1.1.3.tar.bz2
wget https://www.kernel.org/pub/software/network/wireless-regdb/wireless-regdb-2014.06.13.tar.gz
tar jxf crda-1.1.3.tar.bz2
tar zxf wireless-regdb-2014.06.13.tar.gz
check your current CRDA country code:
Code:
iw reg get
country GR:
(2402 - 2482 @ 40), (N/A, 20)
(5170 - 5250 @ 80), (N/A, 20)
(5250 - 5330 @ 80), (N/A, 20), DFS
(5490 - 5710 @ 80), (N/A, 27), DFS
(57240 - 65880 @ 2160), (N/A, 40), NO-OUTDOOR
if country code is set to 00 (double zero) that means that is set to world regulatory domain.
You can set by: (GR = Greece in my example)
--------------------------------------------------
wireless-regdb:
open db.txt and search for the country that you intersting to change the rules:
Code:
leafpad /root/wireless-regdb-2014.06.13/db.txt
# or
nano /root/wireless-regdb-2014.06.13/db.txt
in my example from:
Quote:
country GR: DFS-ETSI
(2402 - 2482 @ 40), (20)
(5170 - 5250 @ 80), (20)
(5250 - 5330 @ 80), (20), DFS
(5490 - 5710 @ 80), (27), DFS
# 60 gHz band channels 1-4, ref: Etsi En 302 567
(57240 - 65880 @ 2160), (40), NO-OUTDOOR
to:
Quote:
country GR: DFS-ETSI
(2402 - 2482 @ 40), (30)
(5170 - 5250 @ 80), (20)
(5250 - 5330 @ 80), (20), DFS
(5490 - 5710 @ 80), (27), DFS
# 60 gHz band channels 1-4, ref: Etsi En 302 567
(57240 - 65880 @ 2160), (40), NO-OUTDOOR
save it and exit. (the db.txt file)
Make a backup of your current regulatory.bin file
Code:
mv /lib/crda/regulatory.bin /lib/crda/regulatoryOLD.bin
Compile and copy the new regulatory.bin file:
Code:
cd /root/wireless-regdb-2014.06.13
make
cp /root/wireless-regdb-2014.06.13/regulatory.bin /lib/crda/regulatory.bin
#DO NOT RUN MAKE INSTALL
--------------------------------------------------------
CRDA:
Validating.
Copy pems into our downloaded crda directory in pubkeys.
Code:
cp /root/wireless-regdb-2014.06.13/root.key.pub.pem /root/crda-1.1.3/pubkeys/root.key.pub.pem
cp /root/wireless-regdb-2014.06.13/linville.key.pub.pem /root/crda-1.1.3/pubkeys/linville.key.pub.pem
cp /lib/crda/pubkeys/[email protected] /root/crda-1.1.3/pubkeys/[email protected]
Correct regulatory.bin path in Makefile of crda:
Code:
sed 's%REG_BIN?=/usr/lib/crda/regulatory.bin%REG_BIN?=/lib/crda/regulatory.bin%g' /root/crda-1.1.3/Makefile > /root/crda-1.1.3/Makefile1 && mv /root/crda-1.1.3/Makefile1 /root/crda-1.1.3/Makefile
Compile and install:
Code:
cd /root/crda-1.1.3/
make
make install
Thats it! You can reboot* now or you can:
Code:
modprobe cfg80211 ieee80211_regdom=GR
* No need to reboot. You could also change to another's country code and then back again to the changed one. ie
Code:
iw reg set DE
iw reg set GR
You should see something like:
Quote:
iw reg get
country GR:
(2402 - 2482 @ 40), (N/A, 30)
(5170 - 5250 @ 80), (N/A, 20)
(5250 - 5330 @ 80), (N/A, 20), DFS
(5490 - 5710 @ 80), (N/A, 27), DFS
(57240 - 65880 @ 2160), (N/A, 40), NO-OUTDOOR
The interesting it's not just to allow your card to work in a higher Tx power. The interesting part is that you can remove some other restrictions. ie remove DFS (dynamic frequency selection) of a band, to remove NO-OUTDOOR restriction etc.
Please refer to the link at the beginning for "QUICK DECIBEL UNDERSTANDING"
WARNING
Removing all restrictions is illegal in the United States. This tutorial is only for educational reasons, and if you choose to apply it and break the law, then that is your choice and not mine. Please be careful putting this into action
.
Changing Wifi Txpower during monitor mode
i have a question regarding setting the wifi transmission power while it is in monitor mode(by airmon-ng).
What i needed is to send different wifi packets with different transmission power when the wifi adapter is in monitor mode.So for this purpose, i tried by changing the energy level in the RADIOTAP header for each packets. But i found even if i change the Txpower bit value in radiotap header, the driver is sending at a fixed power(Max txpower allowed to region).
So my question is how airmon-ng is setting the txpower to the maximum of the regulatory value to a region.(/lib/crda/regulatory.bin)? Can we override this value ??
Hope you all understand the question!
Cheers
