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rtl8821au (8821au.ko)

Realtek RTL8821AU Wireless Lan Driver for Linux

• v5.12.5.2 (20210708)
• Based on EDIMAX EW-7811UTC Linux Driver (Version : 1.0.3.4) 2021-09-16
• Support Kernel: 4.15 - 5.11 (Realtek)
• Support up to Kernel 6.3

Specification

• Supported interface modes:
  • IBSS
  • managed
  • AP
  • monitor
  • P2P-client
  • P2P-GO
• Packet injection
• TX power control
• LED control
• Power saving control
• Driver debug log level control
• VHT control
• REGD source selection
• Security:
  • WEP 64/128-bit, WPA, WPA2, WPA3, and 802.1x

Supported adapters

• Realtek RTL8811AU Wireless LAN 802.11ac USB 2.0 Network Adapter
• Realtek RTL8821AU Wireless LAN 802.11ac USB 2.0 Network Adapter
• Edimax EW-7811UTC
• Edimax EW-7811UAC
• Edimax EW-7811DAC
• Edimax EW-7811USC
• Edimax EW-7611UCB
• I-O DATA WN-AC433UA Wireless LAN Adapter
• D-Link DWA-171 rev A1 Wireless AC Dual Band Adapter
• D-Link DWA-172 rev A1 Wireless AC600 Dual Band High-Gain USB Adapter
• Hawking USB WLS 11AC Adapter
• ELECOM WDC-433SU2M2  Wireless Adapter
• ELECOM WDB-433SU2M2  Wireless Adapter
• TRENDnet AC600 Dual Band Wireless USB Adapter
• TP-LINK Archer T2U V3
• TP-LINK Archer T2U Nano V1
• TP-LINK Archer T2U Plus V1
• I-O DATA Realtek Wireless LAN USB 2.0 5G Only Network Adapter
• Planex GW-450S
• Sitecom WiFi High Gain USB Adapter AC600
• ELECOM WDC-433DU2H 11ac Wireless Adapter
• Abocom 802.11ac Wireless LAN Card
• I-O DATA WN-AC433UM Wireless LAN Adapter
• I-O DATA WHG-AC433UM Wireless LAN Adapter
• AirTies Air2520 Wireless USB Adapter
• AirTies Air2525 Wireless USB Adapter
• BUFFALO WI-U2-433DM Wireless LAN Adapter
• BUFFALO WI-U2-433DHP Wireless Lan Adapter
• BUFFALO WLP-U2-433DHP Wireless Lan Adapter
• Netgear A6100
• Obihai OBiWiFi

To support WiFi USB Adapter(s) with new vid/pid(s) which have rtl8821au or rtl8811au chipset.

Tested Linux Distros and Tools

Successful tested injection aireplay-ng -9 <interface>, deauthentication aireplay-ng -0 1 -a <bssid> <interface>.

NO fixed channel 1 issue.

Successful hcxdumptool driver test hcxdumptool -i <interface> --check_driver and capture packets hcxdumptool -i <interface> -o test.pcapng --filterlist_ap=targets.lst --filtermode=2 --enable_status=15 (hcxdumptool -i <interface> -o test.pcapng --filterlist=targets.lst --filtermode=2 --enable_status=15).

Connecting to AP with WPA3 (WPA3-SAE) authentication method (IMPORTANT: Test distro Ubuntu 22.04 kernel 5.15 - NetworkManager 1.36.4 nmcli tool, version 1.36.4. Otherwise use wpa_supplicant).

Start WPA3 (WPA3-SAE) SoftAP.

TX power control tested with SoftAP mode and OpenWrt firmware (OpenWrt 21.02.0 r16279-5cc0535800, Channel Analysis Feature).

• Ubuntu 22.04 (kernel 5.19)
  • Aircrack-ng 1.6
  • hcxdumptool 6.2.6
  • hostapd v2.11-devel-hostap_2_10-309-gc3d389b72
  • wpa_supplicant v2.11-devel-hostap_2_10-309-gc3d389b72

Ubuntu 22.04 (kernel 5.18)

• wpa_supplicant v2.11-devel-hostap_2_10-309-gc3d389b72
• hostapd v2.11-devel-hostap_2_10-309-gc3d389b72
• Aircrack-ng 1.6
• hcxdumptool 6.2.6

Ubuntu 21.10 (kernel 5.17)

• hostapd v2.11-devel-hostap_2_10-151-g3085e1a67
• hcxdumptool 6.2.4
• Aircrack-ng 1.6
• wpa_supplicant v2.11-devel-hostap_2_10-151-g3085e1a67

Ubuntu 21.10 (kernel 5.16)

• Aircrack-ng 1.6
• hcxdumptool 6.2.4
• wpa_supplicant v2.10-devel-hostap_2_9-2398-g8a54c252a
• hostapd v2.10-devel-hostap_2_9-2398-g8a54c252a

Kali Linux 2021.3a (kernel 5.14)

• Aircrack-ng 1.6
• hcxdumptool 5.2.2
• wpa_supplicant v2.10-devel-hostap_2_9-2433-g8d881d942

Kali Linux 2020.3 (kernel 5.9)

• wpa_supplicant v2.10-devel-hostap_2_9-2379-g4775a5f82
• hostapd v2.10-devel-hostap_2_9-2379-g4775a5f82
• Aircrack-ng 1.6
• hcxdumptool 6.1.4

Kali Linux 2019.1a (kernel 4.19)

• Aircrack-ng 1.5.2
• hcxdumptool 5.1.7
• wpa_supplicant v2.10-devel-hostap_2_9-2433-g8d881d942

Ubuntu 21.10 (kernel 5.15)

• wpa_supplicant v2.10-devel-hostap_2_9-2398-g8a54c252a
• hostapd v2.10-devel-hostap_2_9-2398-g8a54c252a
• Aircrack-ng 1.6
• hcxdumptool 6.2.4

Ubuntu 21.10 (kernel 5.13)

• Aircrack-ng 1.6
• hcxdumptool 6.2.0
• hostapd v2.10-devel-hostap_2_9-2398-g8a54c252a
• wpa_supplicant v2.10-devel-hostap_2_9-2398-g8a54c252a

Ubuntu 12.04 (kernel 3.4)

• Aircrack-ng 1.5.2
• hcxdumptool 4.2.1

Ubuntu 11.10 (kernel 3.0)

• Aircrack-ng 1.5.2
• hcxdumptool 4.2.1

Linux Mint 20.2 MATE (kernel 5.4)

• wpa_supplicant v2.10-devel-hostap_2_9-2486-gbb6fa62b3
• hostapd v2.10-devel-hostap_2_9-2486-gbb6fa62b3
• hcxdumptool 6.1.6
• Aircrack-ng 1.6

Ubuntu 12.10 (kernel 3.5)

• Aircrack-ng 1.5.2
• hcxdumptool 4.2.1

Ubuntu 13.04 (kernel 3.8)

• Aircrack-ng 1.5.2
• hcxdumptool 5.1.4

Ubuntu 21.04 (kernel 5.11)

• Aircrack-ng 1.6
• hcxdumptool 6.1.6
• wpa_supplicant v2.10-devel-hostap_2_9-2374-g9ef8491d9

HOW TO

Install

Download source:

git clone https://github.com/ivanovborislav/rtl8821au.git
cd rtl8821au

Install missing packages:

sudo apt-get install bc build-essential

Install linux headers:

sudo apt-get install linux-headers-$(uname -r)

or

apt-cache search linux-headers
sudo apt-get install linux-headers-5.14.0-kali4-amd64 (for example)
apt-cache search linux-image
sudo apt-get install linux-image-5.14.0-kali4-amd64 (for example)

Compile:

make
sudo make install

or

chmod +x install.sh
./install.sh -i

Raspberry Pi:

Edit Makefile:

Ln142 - CONFIG_PLATFORM_I386_PC = y to CONFIG_PLATFORM_I386_PC = n

Ln143 - CONFIG_PLATFORM_RPI_ARM = n to CONFIG_PLATFORM_RPI_ARM = y for ARM

or

Ln144 - CONFIG_PLATFORM_RPI_ARM64 = n to CONFIG_PLATFORM_RPI_ARM64 = y for ARM64

DKMS installation

sudo git clone "https://github.com/ivanovborislav/rtl8821au.git" /usr/src/rtl8821au-5.12.5.2
sudo dkms add -m rtl8821au -v 5.12.5.2
sudo dkms autoinstall
dkms status

or

sudo git clone "https://github.com/ivanovborislav/rtl8821au.git" /usr/src/rtl8821au-5.12.5.2
sudo dkms add -m rtl8821au -v 5.12.5.2
sudo dkms build -m rtl8821au -v 5.12.5.2
sudo dkms install -m rtl8821au -v 5.12.5.2
dkms status

Monitor mode

sudo airmon-ng check kill
sudo ip link set <interface> down
sudo iw dev <interface> set type monitor
sudo ip link set <interface> up

Managed mode

sudo ip link set <interface> down
sudo iw dev <interface> set type managed
sudo ip link set <interface> up
sudo systemctl restart NetworkManager (sudo service network-manager restart)

TX power control

Note: Set TX power before start SoftAP mode. ...set txpower fixed 3000 = txpower 30.00 dBm.

sudo iw dev <interface> set txpower fixed 3000

Driver options

Change driver options during inserting driver module

Remove (unload) a module from the Linux kernel.

sudo rmmod /lib/modules/$(uname -r)/kernel/drivers/net/wireless/8821au.ko

Insert (load) a module into the Linux kernel.

sudo insmod /lib/modules/$(uname -r)/kernel/drivers/net/wireless/8821au.ko rtw_ips_mode=1 rtw_drv_log_level=4 rtw_power_mgnt=2 rtw_led_ctrl=1

Change driver options loading from file

Create a file 8821au.conf containing options 8821au rtw_ips_mode=1 rtw_drv_log_level=4 rtw_power_mgnt=2 rtw_led_ctrl=1. Copy a file to /etc/modprobe.d/ directory.

sudo cp -f 8821au.conf /etc/modprobe.d

Power saving control.

IPS (Inactive Power Saving) Function, rtw_ips_mode=

0:Disable IPS
1:Enable IPS (default)

LPS (Leisure Power Saving) Function, rtw_power_mgnt=

0:Disable LPS
1:Enable LPS
2:Enable LPS with clock gating (default)

Driver debug log level control, rtw_drv_log_level=

0:_DRV_NONE_
1:_DRV_ALWAYS_
2:_DRV_ERR_
3:_DRV_WARNING_
4:_DRV_INFO_ (default)
5:_DRV_DEBUG_
6:_DRV_MAX_

Driver LED control, rtw_led_ctrl=

0:led off
1:led blink (default)
2:led on

Driver VHT control, rtw_vht_enable=

0:disable
1:enable (default)
2:force auto enable

Driver REGD source selection, rtw_regd_src=

0:Realtek defined
1:OS (default, get channel plan from OS)

Connecting with wpa_supplicant

Example wpa_supplicant.conf with WPA3-Personal (WPA3-SAE).

update_config=1
ctrl_interface=/var/run/wpa_supplicant
country=EN
p2p_no_group_iface=1
sae_groups=19 20 21

network={
	ssid="WPA3"
	proto=RSN
	key_mgmt=SAE
	pairwise=CCMP
	group=CCMP
	ieee80211w=2
	psk="1234567890"
}

Now start...

sudo systemctl stop NetworkManager
sudo killall wpa_supplicant
sudo wpa_supplicant -B -i <interface> -c wpa_supplicant.conf
sudo dhclient <interface>

Start SoftAP mode

Example hostapd.conf with WPA3-Personal (WPA3-SAE) 2.4GHz.

driver=nl80211
ctrl_interface=/var/run/hostapd
ctrl_interface_group=0
ssid=WPA3
country_code=EN
hw_mode=g
channel=6
beacon_int=100
dtim_period=1
max_num_sta=16
rts_threshold=2347
fragm_threshold=2346
ignore_broadcast_ssid=0
wmm_enabled=1
ieee80211n=1
ht_capab=[HT40-][SHORT-GI-20][SHORT-GI-40][RX-STBC1][MAX-AMSDU-7935][DSSS_CCK-40]

auth_algs=1
wpa=2
wpa_passphrase=1234567890
wpa_key_mgmt=SAE
wpa_pairwise=CCMP
rsn_pairwise=CCMP
ieee80211w=2
sae_groups=19 20 21
sae_require_mfp=1

Example hostapd.conf with WPA3-Personal (WPA3-SAE) 5GHz.

CAUTION: Allow width: 80 MHz, insmod 8821au.ko rtw_vht_enable=2.

driver=nl80211
ctrl_interface=/var/run/hostapd
ctrl_interface_group=0
ssid=WPA3_5GHz
country_code=EN
hw_mode=a
channel=36
beacon_int=100
dtim_period=1
max_num_sta=16
rts_threshold=2347
fragm_threshold=2346
ignore_broadcast_ssid=0
wmm_enabled=1
ieee80211n=1
ht_capab=[HT40+][SHORT-GI-20][SHORT-GI-40][MAX-AMSDU-7935][DSSS_CCK-40]
ieee80211ac=1
vht_capab=[MAX-MPDU-11454][SHORT-GI-80][RX-STBC1][SU-BEAMFORMEE][HTC-VHT][MAX-A-MPDU-LEN-EXP7]
vht_oper_chwidth=1
vht_oper_centr_freq_seg0_idx=42

auth_algs=1
wpa=2
wpa_passphrase=1234567890
wpa_key_mgmt=SAE
wpa_pairwise=CCMP
rsn_pairwise=CCMP
ieee80211w=2
sae_groups=19 20 21
sae_require_mfp=1

Now start...

sudo killall hostapd
sudo hostapd -i <interface> hostapd.conf

Kali NetHunter Kernel module Samsung Galaxy S5

Test devices

• TP-Link Archer T2U Plus V1

• Linksys WRT1200AC V2

  • OpenWrt 21.02.0 r16279-5cc0535800 / LuCI openwrt-21.02 branch git-21.231.26241-422c175

config wifi-iface 'default_radio1'
	option device 'radio1'
	option network 'lan'
	option mode 'ap'
	option macaddr '30:23:03:XX:XX:XX'
	option ssid 'WPA3'
	option encryption 'sae'
	option key '1234567890'
	option ieee80211w '2'

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