A UDP bridge over a wifibroadcast link
Based on code and ideas from the OpenHD, EZ-WifiBroadcast, and svpcom wifibroadcast
sudo apt-get install -y libpcap-dev python3-pyudev libpcap0.8-dev python3-pip python3-setuptools python3-wheel python3-pyudev cmake firmware-ath9k-htc liblog4cpp5-dev libnl-3-dev libnl-genl-3-dev libudev-dev
git submodule update --init
mkdir build
cd build
cmake ..
make
cmake -DCMAKE_INSTALL_PREFIX=<install directory> ..
make install
cmake -DCMAKE_INSTALL_PREFIX=/ ..
sudo make install
sudo ../scripts/postinst
cpack
Wifibroadcast_bridge consists of a single program (wfb_bridge) that configures the wifi interface(s), and sends and receives to/from multiple UDP ports. There is a single configuration file to configure the interfaces and ports, which is normally stored in /etc/wfb_bridge.conf. The configuration parameters are documented in the configuration file.
This package adds a single systemd services that can be started, stopped, and enabled at boot time.
sudo systemctl start wfb_bridge
sudo systemctl stop wfb_bridge
sudo systemctl enable wfb_bridge
sudo systemctl restart wfb_bridge
It is highly recommended to use rtl8812au based wifi adapters with version v5.6.4.2 of the aircract-ng wifi driver (https://github.com/aircrack-ng/rtl8812au). This has been well tested and works very well at bit rates at least up to 18Mbps or so.
The following patch is required to dynamically change the transmit power:
--- a/hal/rtl8812a/rtl8812a_phycfg.c
+++ b/hal/rtl8812a/rtl8812a_phycfg.c
@@ -39,7 +39,7 @@ int transmit_power_boost = 2;
// Transmit Power Override
// This value completely overrides the driver's calculations and uses only one value for all transmissions.
// Zero disables it. Default: 0
-int transmit_power_override = 0;
+extern int rtw_tx_pwr_idx_override;
/* Manual Transmit Power Control */
@@ -592,8 +592,8 @@ PHY_GetTxPowerIndex_8812A(
by_rate_diff = by_rate_diff > limit ? limit : by_rate_diff;
power_idx = base_idx + by_rate_diff + tpt_offset + extra_bias + transmit_power_boost;
- if (transmit_power_override != 0)
- power_idx = transmit_power_override;
+ if (rtw_tx_pwr_idx_override)
+ power_idx = rtw_tx_pwr_idx_override;
if (power_idx < 1)
power_idx = 1;
diff --git a/os_dep/linux/os_intfs.c b/os_dep/linux/os_intfs.c
index 1085d6c..d6a3075 100644
--- a/os_dep/linux/os_intfs.c
+++ b/os_dep/linux/os_intfs.c
@@ -23,6 +23,8 @@ MODULE_AUTHOR("Realtek Semiconductor Corp.");
MODULE_VERSION(DRIVERVERSION);
/* module param defaults */
+int rtw_tx_pwr_idx_override = 45;
+module_param(rtw_tx_pwr_idx_override, int, 0644);
int rtw_chip_version = 0x00;
int rtw_rfintfs = HWPI;
int rtw_lbkmode = 0;/* RTL8712_AIR_TRX; */It is critical to add the following options to /etc/modprobe.d/rtl8812au.conf:
options 88XXau rtw_monitor_disable_1m=1
This option allows the monitor mode interface to transit at full data rate. Without this option, monitor mode data transfers are limited to 1Mbps!
The ar9271 (and other devices supported by the ath9k kernel driver) have also been used, but they do not support bit rates above around 8-10 Mbps, require multiple kernel patches, and generally do not perform nearly as well as the rtl8812au.