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WPA_SUPPLICANT(8)                                            WPA_SUPPLICANT(8)

       wpa_supplicant - Wi-Fi Protected Access client and IEEE 802.1X supplicant

       wpa_supplicant [ -BddfhKLqqtuvW ] [ -iifname ] [ -cconfig file ] [ -Ddriver ] [ -PPID_file ] [ -foutput file ]

       Wireless  networks  do  not require physical access to the network equipment in the same way as wired networks.
       This makes it easier for unauthorized users to passively monitor a network and capture all transmitted  frames.
       In addition, unauthorized use of the network is much easier. In many cases, this can happen even without user's
       explicit knowledge since the wireless LAN adapter may have been configured to automatically join any  available

       Link-layer  encryption  can be used to provide a layer of security for wireless networks. The original wireless
       LAN standard, IEEE 802.11, included a simple encryption mechanism, WEP. However, that proved to  be  flawed  in
       many  areas and network protected with WEP cannot be consider secure. IEEE 802.1X authentication and frequently
       changed dynamic WEP keys can be used to improve the network security, but  even  that  has  inherited  security
       issues  due to the use of WEP for encryption. Wi-Fi Protected Access and IEEE 802.11i amendment to the wireless
       LAN standard introduce a much improvement mechanism for securing wireless networks. IEEE 802.11i  enabled  net-
       works  that  are  using  CCMP (encryption mechanism based on strong cryptographic algorithm AES) can finally be
       called secure used for applications which require efficient protection against unauthorized access.

       wpa_supplicant is an implementation of the WPA Supplicant component, i.e., the part that  runs  in  the  client
       stations. It implements WPA key negotiation with a WPA Authenticator and EAP authentication with Authentication
       Server. In addition, it controls the roaming and IEEE 802.11 authentication/association  of  the  wireless  LAN

       wpa_supplicant  is designed to be a "daemon" program that runs in the background and acts as the backend compo-
       nent controlling the wireless connection. wpa_supplicant supports separate frontend  programs  and  an  example
       text-based frontend, wpa_cli, is included with wpa_supplicant.

       Before  wpa_supplicant  can do its work, the network interface must be available.  That means that the physical
       device must be present and enabled, and the driver for the device must be loaded. The daemon will exit  immedi-
       ately if the device is not already available.

       After  wpa_supplicant  has  configured the network device, higher level configuration such as DHCP may proceed.
       There are a variety of ways to integrate wpa_supplicant into a machine's networking scripts, a few of which are
       described in sections below.

       The following steps are used when associating with an AP using WPA:

       ? wpa_supplicant requests the kernel driver to scan neighboring BSSes

       ? wpa_supplicant selects a BSS based on its configuration

       ? wpa_supplicant requests the kernel driver to associate with the chosen BSS

       ? If  WPA-EAP:  integrated  IEEE  802.1X Supplicant completes EAP authentication with the authentication server
         (proxied by the Authenticator in the AP)

       ? If WPA-EAP: master key is received from the IEEE 802.1X Supplicant

       ? If WPA-PSK: wpa_supplicant uses PSK as the master session key

       ? wpa_supplicant completes WPA 4-Way Handshake and Group Key Handshake with the Authenticator (AP)

       ? wpa_supplicant configures encryption keys for unicast and broadcast

       ? normal data packets can be transmitted and received

       Supported WPA/IEEE 802.11i features:

       ? WPA-PSK ("WPA-Personal")

       ? WPA with EAP (e.g., with RADIUS authentication server) ("WPA-Enterprise")  Following  authentication  methods
         are supported with an integrate IEEE 802.1X Supplicant:

         ? EAP-TLS

         ? EAP-PEAP/MSCHAPv2 (both PEAPv0 and PEAPv1)

         ? EAP-PEAP/TLS (both PEAPv0 and PEAPv1)

         ? EAP-PEAP/GTC (both PEAPv0 and PEAPv1)

         ? EAP-PEAP/OTP (both PEAPv0 and PEAPv1)

         ? EAP-PEAP/MD5-Challenge (both PEAPv0 and PEAPv1)

         ? EAP-TTLS/EAP-MD5-Challenge

         ? EAP-TTLS/EAP-GTC

         ? EAP-TTLS/EAP-OTP

         ? EAP-TTLS/EAP-MSCHAPv2

         ? EAP-TTLS/EAP-TLS

         ? EAP-TTLS/MSCHAPv2

         ? EAP-TTLS/MSCHAP

         ? EAP-TTLS/PAP

         ? EAP-TTLS/CHAP

         ? EAP-SIM

         ? EAP-AKA

         ? EAP-PSK

         ? EAP-PAX

         ? LEAP (note: requires special support from the driver for IEEE 802.11 authentication)

         ? (following  methods are supported, but since they do not generate keying material, they cannot be used with
           WPA or IEEE 802.1X WEP keying)

         ? EAP-MD5-Challenge

         ? EAP-MSCHAPv2

         ? EAP-GTC

         ? EAP-OTP

       ? key management for CCMP, TKIP, WEP104, WEP40

       ? RSN/WPA2 (IEEE 802.11i)

         ? pre-authentication

         ? PMKSA caching

       A summary of available driver backends is below. Support for each of the driver backends is chosen at  wpa_sup-
       plicant  compile time. For a list of supported driver backends that may be used with the -D option on your sys-
       tem, refer to the help output of wpa_supplicant (wpa_supplicant -h).

       hostap (default) Host AP driver (Intersil Prism2/2.5/3).  (this can also be used with Linuxant DriverLoader).

       hermes Agere Systems Inc. driver (Hermes-I/Hermes-II).

              MADWIFI 802.11 support (Atheros, etc.).

       atmel  ATMEL AT76C5XXx (USB, PCMCIA).

       wext   Linux wireless extensions (generic).

              Linux ndiswrapper.

              Broadcom wl.o driver.

       ipw    Intel ipw2100/2200 driver.

       wired  wpa_supplicant wired Ethernet driver

              wpa_supplicant Broadcom switch driver

       bsd    BSD 802.11 support (Atheros, etc.).

       ndis   Windows NDIS driver.

       Most command line options have global scope. Some are given per interface, and are only valid if at  least  one
       -i  option is specified, otherwise they're ignored. Option groups for different interfaces must be separated by
       -N option.

       -b br_ifname
              Optional bridge interface name. (Per interface)

       -B     Run daemon in the background.

       -c filename
              Path to configuration file. (Per interface)

       -C ctrl_interface
              Path to ctrl_interface socket (Per interface. Only used if -c is not).

       -i ifname
              Interface to listen on. Multiple instances of this option can be present, one per  interface,  separated
              by -N option (see below).

       -d     Increase debugging verbosity (-dd even more).

       -D driver
              Driver  to  use  (can  be  multiple  drivers:  nl80211,wext).  (Per interface, see the available options

       -f output file
              Log output to specified file instead of stdout.

       -g global ctrl_interface
              Path to global ctrl_interface socket. If specified, interface definitions may be omitted.

       -K     Include keys (passwords, etc.) in debug output.

       -t     Include timestamp in debug messages.

       -h     Help.  Show a usage message.

       -L     Show license (GPL and BSD).

       -p     Driver parameters. (Per interface)

       -P PID_file
              Path to PID file.

       -q     Decrease debugging verbosity (-qq even less).

       -u     Enabled DBus control interface. If enabled, interface definitions may be omitted.

       -v     Show version.

       -W     Wait for a control interface monitor before starting.

       -N     Start describing new interface.

       In most common cases, wpa_supplicant is started with:

              wpa_supplicant -B -c/etc/wpa_supplicant.conf -iwlan0

       This makes the process fork into background.

       The easiest way to debug problems, and to get debug log for bug reports, is to start  wpa_supplicant  on  fore-
       ground with debugging enabled:

              wpa_supplicant -c/etc/wpa_supplicant.conf -iwlan0 -d

       If  the  specific  driver  wrapper  is not known beforehand, it is possible to specify multiple comma separated
       driver wrappers on the command line. wpa_supplicant will use the first driver wrapper that is able to  initial-
       ize the interface.

              wpa_supplicant -Dnl80211,wext -c/etc/wpa_supplicant.conf -iwlan0

       wpa_supplicant  can control multiple interfaces (radios) either by running one process for each interface sepa-
       rately or by running just one process and list of options at command line. Each interface is separated with  -N
       argument. As an example, following command would start wpa_supplicant for two interfaces:

              wpa_supplicant \
                   -c wpa1.conf -i wlan0 -D hostap -N \
                   -c wpa2.conf -i ath0 -D madwifi

       Current hardware/software requirements:

       ? Linux kernel 2.4.x or 2.6.x with Linux Wireless Extensions v15 or newer

       ? FreeBSD 6-CURRENT

       ? Microsoft Windows with WinPcap (at least WinXP, may work with other versions)

       Host AP driver for Prism2/2.5/3 (development snapshot/v0.2.x)
              (  Driver  needs  to  be  set  in  Managed mode (iwconfig wlan0 mode managed).
              Please note that station firmware version needs to be 1.7.0 or newer to work in WPA mode.

       Linuxant DriverLoader
              ( with Windows NDIS driver for your wlan card supporting WPA.

       Agere Systems Inc. Linux Driver
              ( Please note that the driver interface file (driver_hermes.c) and
              hardware  specific  include  files are not included in the wpa_supplicant distribution. You will need to
              copy these from the source package of the Agere driver.

       madwifi driver for cards based on Atheros chip set (ar521x)
              ( Please note that you will need to modify  the  wpa_supplicant
              .config  file  to use the correct path for the madwifi driver root directory (CFLAGS += -I../madwifi/wpa
              line in example defconfig).

       ATMEL AT76C5XXx driver for USB and PCMCIA cards

       Linux ndiswrapper
              ( with Windows NDIS driver.

       Broadcom wl.o driver
              This is a generic Linux driver for Broadcom IEEE 802.11a/g cards.  However,  it  is  proprietary  driver
              that  is  not  publicly  available  except  for couple of exceptions, mainly Broadcom-based APs/wireless
              routers that use  Linux.  The  driver  binary  can  be  downloaded,  e.g.,  from  Linksys  support  site
              ( for Linksys WRT54G. The GPL tarball includes cross-compiler and
              the needed header file, wlioctl.h, for compiling wpa_supplicant.  This driver support in  wpa_supplicant
              is  expected  to  work  also  with  other devices based on Broadcom driver (assuming the driver includes
              client mode support).

        Intel ipw2100 driver

       Intel ipw2200 driver

       Linux wireless extensions
              In theory, any driver that supports Linux wireless extensions can be used with IEEE  802.1X  (i.e.,  not
              WPA) when using ap_scan=0 option in configuration file.

       Wired Ethernet drivers
              Use ap_scan=0.

       BSD net80211 layer (e.g., Atheros driver)
              At the moment, this is for FreeBSD 6-CURRENT branch.

       Windows NDIS
              The  current Windows port requires WinPcap (  See README-Windows.txt for more

       wpa_supplicant was designed to be portable for different drivers and operating systems. Hopefully, support  for
       more  wlan  cards and OSes will be added in the future. See developer.txt for more information about the design
       of wpa_supplicant and porting to other drivers. One main goal is to add full WPA/WPA2 support to Linux wireless
       extensions  to allow new drivers to be supported without having to implement new driver-specific interface code
       in wpa_supplicant.

       The wpa_supplicant system consists of the following components:

              the configuration file describing all networks that the user wants the computer to connect to.

              the program that directly interacts with the network interface.

              the client program that provides a high-level interface to the functionality of the daemon.

              a utility needed to construct wpa_supplicant.conf files that include encrypted passwords.

       First, make a configuration file, e.g.  /etc/wpa_supplicant.conf, that describes the networks  you  are  inter-
       ested in.  See wpa_supplicant.conf(5) for details.

       Once  the  configuration  is ready, you can test whether the configuration works by running wpa_supplicant with
       following command to start it on foreground with debugging enabled:

              wpa_supplicant -iwlan0 -c/etc/wpa_supplicant.conf -d

       Assuming everything goes fine, you can start using following command  to  start  wpa_supplicant  on  background
       without debugging:

              wpa_supplicant -iwlan0 -c/etc/wpa_supplicant.conf -B

       Please  note that if you included more than one driver interface in the build time configuration (.config), you
       may need to specify which interface to use by including -D<driver name> option on the command line.

       For example, following small changes to pcmcia-cs scripts can be used to enable WPA support:

       Add MODE="Managed" and WPA="y" to the network scheme in /etc/pcmcia/wireless.opts.

       Add the following block to the end of start action handler in /etc/pcmcia/wireless:

              if [ "$WPA" = "y" -a -x /usr/local/bin/wpa_supplicant ]; then
                  /usr/local/bin/wpa_supplicant -B -c/etc/wpa_supplicant.conf -i$DEVICE

       Add the following block to the end of stop action handler (may need to be  separated  from  other  actions)  in

              if [ "$WPA" = "y" -a -x /usr/local/bin/wpa_supplicant ]; then
                  killall wpa_supplicant

       This will make cardmgr start wpa_supplicant when the card is plugged in.

       wpa_background(8) wpa_supplicant.conf(5) wpa_cli(8) wpa_passphrase(8)

       wpa_supplicant is copyright (c) 2003-2007, Jouni Malinen <> and contributors.  All Rights Reserved.

       This  program is dual-licensed under both the GPL version 2 and BSD license. Either license may be used at your

                               07 September 2010             WPA_SUPPLICANT(8)