Based on kernel version 3.19. Page generated on 2015-02-13 21:22 EST.
1 mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211 2 Copyright (c) 2008, Jouni Malinen <email@example.com> 3 4 This program is free software; you can redistribute it and/or modify 5 it under the terms of the GNU General Public License version 2 as 6 published by the Free Software Foundation. 7 8 9 Introduction 10 11 mac80211_hwsim is a Linux kernel module that can be used to simulate 12 arbitrary number of IEEE 802.11 radios for mac80211. It can be used to 13 test most of the mac80211 functionality and user space tools (e.g., 14 hostapd and wpa_supplicant) in a way that matches very closely with 15 the normal case of using real WLAN hardware. From the mac80211 view 16 point, mac80211_hwsim is yet another hardware driver, i.e., no changes 17 to mac80211 are needed to use this testing tool. 18 19 The main goal for mac80211_hwsim is to make it easier for developers 20 to test their code and work with new features to mac80211, hostapd, 21 and wpa_supplicant. The simulated radios do not have the limitations 22 of real hardware, so it is easy to generate an arbitrary test setup 23 and always reproduce the same setup for future tests. In addition, 24 since all radio operation is simulated, any channel can be used in 25 tests regardless of regulatory rules. 26 27 mac80211_hwsim kernel module has a parameter 'radios' that can be used 28 to select how many radios are simulated (default 2). This allows 29 configuration of both very simply setups (e.g., just a single access 30 point and a station) or large scale tests (multiple access points with 31 hundreds of stations). 32 33 mac80211_hwsim works by tracking the current channel of each virtual 34 radio and copying all transmitted frames to all other radios that are 35 currently enabled and on the same channel as the transmitting 36 radio. Software encryption in mac80211 is used so that the frames are 37 actually encrypted over the virtual air interface to allow more 38 complete testing of encryption. 39 40 A global monitoring netdev, hwsim#, is created independent of 41 mac80211. This interface can be used to monitor all transmitted frames 42 regardless of channel. 43 44 45 Simple example 46 47 This example shows how to use mac80211_hwsim to simulate two radios: 48 one to act as an access point and the other as a station that 49 associates with the AP. hostapd and wpa_supplicant are used to take 50 care of WPA2-PSK authentication. In addition, hostapd is also 51 processing access point side of association. 52 53 54 # Build mac80211_hwsim as part of kernel configuration 55 56 # Load the module 57 modprobe mac80211_hwsim 58 59 # Run hostapd (AP) for wlan0 60 hostapd hostapd.conf 61 62 # Run wpa_supplicant (station) for wlan1 63 wpa_supplicant -Dwext -iwlan1 -c wpa_supplicant.conf 64 65 66 More test cases are available in hostap.git: 67 git://w1.fi/srv/git/hostap.git and mac80211_hwsim/tests subdirectory 68 (http://w1.fi/gitweb/gitweb.cgi?p=hostap.git;a=tree;f=mac80211_hwsim/tests)