mac80211_hwsim.rst (3083B)
1:orphan: 2 3.. SPDX-License-Identifier: GPL-2.0 4.. include:: <isonum.txt> 5 6=================================================================== 7mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211 8=================================================================== 9 10:Copyright: |copy| 2008, Jouni Malinen <j@w1.fi> 11 12This program is free software; you can redistribute it and/or modify 13it under the terms of the GNU General Public License version 2 as 14published by the Free Software Foundation. 15 16 17Introduction 18============ 19 20mac80211_hwsim is a Linux kernel module that can be used to simulate 21arbitrary number of IEEE 802.11 radios for mac80211. It can be used to 22test most of the mac80211 functionality and user space tools (e.g., 23hostapd and wpa_supplicant) in a way that matches very closely with 24the normal case of using real WLAN hardware. From the mac80211 view 25point, mac80211_hwsim is yet another hardware driver, i.e., no changes 26to mac80211 are needed to use this testing tool. 27 28The main goal for mac80211_hwsim is to make it easier for developers 29to test their code and work with new features to mac80211, hostapd, 30and wpa_supplicant. The simulated radios do not have the limitations 31of real hardware, so it is easy to generate an arbitrary test setup 32and always reproduce the same setup for future tests. In addition, 33since all radio operation is simulated, any channel can be used in 34tests regardless of regulatory rules. 35 36mac80211_hwsim kernel module has a parameter 'radios' that can be used 37to select how many radios are simulated (default 2). This allows 38configuration of both very simply setups (e.g., just a single access 39point and a station) or large scale tests (multiple access points with 40hundreds of stations). 41 42mac80211_hwsim works by tracking the current channel of each virtual 43radio and copying all transmitted frames to all other radios that are 44currently enabled and on the same channel as the transmitting 45radio. Software encryption in mac80211 is used so that the frames are 46actually encrypted over the virtual air interface to allow more 47complete testing of encryption. 48 49A global monitoring netdev, hwsim#, is created independent of 50mac80211. This interface can be used to monitor all transmitted frames 51regardless of channel. 52 53 54Simple example 55============== 56 57This example shows how to use mac80211_hwsim to simulate two radios: 58one to act as an access point and the other as a station that 59associates with the AP. hostapd and wpa_supplicant are used to take 60care of WPA2-PSK authentication. In addition, hostapd is also 61processing access point side of association. 62 63:: 64 65 66 # Build mac80211_hwsim as part of kernel configuration 67 68 # Load the module 69 modprobe mac80211_hwsim 70 71 # Run hostapd (AP) for wlan0 72 hostapd hostapd.conf 73 74 # Run wpa_supplicant (station) for wlan1 75 wpa_supplicant -Dnl80211 -iwlan1 -c wpa_supplicant.conf 76 77 78More test cases are available in hostap.git: 79git://w1.fi/srv/git/hostap.git and mac80211_hwsim/tests subdirectory 80(http://w1.fi/gitweb/gitweb.cgi?p=hostap.git;a=tree;f=mac80211_hwsim/tests)