<!doctype refentry PUBLIC "-//OASIS//DTD DocBook V4.1//EN"><refentry>  <refmeta>    <refentrytitle>wpa_supplicant</refentrytitle>    <manvolnum>8</manvolnum>  </refmeta>  <refnamediv>    <refname>wpa_supplicant</refname>    <refpurpose>Wi-Fi Protected Access client and IEEE 802.1X supplicant</refpurpose>  </refnamediv>  <refsynopsisdiv>    <cmdsynopsis>      <command>wpa_supplicant</command>      <arg>-BddehLqqvw</arg>      <arg>-i<replaceable>ifname</replaceable></arg>      <arg>-c<replaceable>config file</replaceable></arg>      <arg>-D<replaceable>driver</replaceable></arg>      <arg>-P<replaceable>PID_file</replaceable></arg>    </cmdsynopsis>  </refsynopsisdiv>  <refsect1>    <title>Overview</title>    <para>    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    network.    </para>    <para>    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 networks 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.    </para>    <para><command>wpa_supplicant</command> 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 driver.</para>    <para><command>wpa_supplicant</command> is designed to be a    "daemon" program that runs in the background and acts as the    backend component controlling the wireless    connection. <command>wpa_supplicant</command> supports separate    frontend programs and an example text-based frontend,    <command>wpa_cli</command>, is included with    wpa_supplicant.</para>    <para>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 have be    loaded.  Note, however, that the '-w' option of the wpa_supplicant    daemon instructs the daemon to continue running and to wait for    the interface to become available.  Without the '-w' option, the    daemon will exit immediately if the device is not already    available.</para>    <para>After <command>wpa_supplicant</command> 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.</para>    <para>The following steps are used when associating with an AP    using WPA:</para>    <itemizedlist>      <listitem>	<para><command>wpa_supplicant</command> requests the kernel	driver to scan neighboring BSSes</para>      </listitem>      <listitem>	<para><command>wpa_supplicant</command> selects a BSS based on	its configuration</para>      </listitem>      <listitem>	<para><command>wpa_supplicant</command> requests the kernel        driver to associate with the chosen BSS</para>      </listitem>      <listitem>	<para>If WPA-EAP: integrated IEEE 802.1X Supplicant or        external Xsupplicant completes EAP authentication with the        authentication server (proxied by the Authenticator in the        AP)</para>      </listitem>      <listitem>	<para>If WPA-EAP: master key is received from the IEEE 802.1X	Supplicant</para>      </listitem>      <listitem>	<para>If WPA-PSK: <command>wpa_supplicant</command> uses PSK	as the master session key</para>      </listitem>      <listitem>	<para><command>wpa_supplicant</command> completes WPA 4-Way        Handshake and Group Key Handshake with the Authenticator        (AP)</para>      </listitem>      <listitem>	<para><command>wpa_supplicant</command> configures encryption	keys for unicast and broadcast</para>      </listitem>      <listitem>	<para>normal data packets can be transmitted and received</para>      </listitem>    </itemizedlist>  </refsect1>  <refsect1>    <title>Supported Features</title>    <para>Supported WPA/IEEE 802.11i features:</para>    <itemizedlist>      <listitem>	<para>WPA-PSK ("WPA-Personal")</para>      </listitem>      <listitem>	<para>WPA with EAP (e.g., with RADIUS authentication server)       ("WPA-Enterprise") Following authentication methods are       supported with an integrate IEEE 802.1X Supplicant:</para>	<itemizedlist>	  <listitem>	    <para>EAP-TLS</para>	  </listitem>	</itemizedlist>	<itemizedlist>	  <listitem>	    <para>EAP-PEAP/MSCHAPv2 (both PEAPv0 and PEAPv1)</para>	  </listitem>	  <listitem>	    <para>EAP-PEAP/TLS (both PEAPv0 and PEAPv1)</para>	  </listitem>	  <listitem>	    <para>EAP-PEAP/GTC (both PEAPv0 and PEAPv1)</para>	  </listitem>	  <listitem>	    <para>EAP-PEAP/OTP (both PEAPv0 and PEAPv1)</para>	  </listitem>	  <listitem>	    <para>EAP-PEAP/MD5-Challenge (both PEAPv0 and PEAPv1)</para>	  </listitem>	  <listitem>	    <para>EAP-TTLS/EAP-MD5-Challenge</para>	  </listitem>	  <listitem>	    <para>EAP-TTLS/EAP-GTC</para>	  </listitem>          <listitem><para>EAP-TTLS/EAP-OTP</para></listitem>          <listitem><para>EAP-TTLS/EAP-MSCHAPv2</para></listitem>          <listitem><para>EAP-TTLS/EAP-TLS</para></listitem>          <listitem><para>EAP-TTLS/MSCHAPv2</para></listitem>          <listitem><para>EAP-TTLS/MSCHAP</para></listitem>          <listitem><para>EAP-TTLS/PAP</para></listitem>          <listitem><para>EAP-TTLS/CHAP</para></listitem>          <listitem><para>EAP-SIM</para></listitem>          <listitem><para>EAP-AKA</para></listitem>          <listitem><para>EAP-PSK</para></listitem>          <listitem><para>EAP-PAX</para></listitem>          <listitem><para>LEAP (note: requires special support from          the driver for IEEE 802.11 authentication)</para></listitem>          <listitem><para>(following methods are supported, but since          they do not generate keying material, they cannot be used          with WPA or IEEE 802.1X WEP keying)</para></listitem>          <listitem><para>EAP-MD5-Challenge </para></listitem>          <listitem><para>EAP-MSCHAPv2</para></listitem>          <listitem><para>EAP-GTC</para></listitem>          <listitem><para>EAP-OTP</para></listitem>	</itemizedlist>      </listitem>      <listitem>	<para>key management for CCMP, TKIP, WEP104, WEP40</para>      </listitem>      <listitem>	<para>RSN/WPA2 (IEEE 802.11i)</para>	<itemizedlist>	  <listitem>	    <para>pre-authentication</para>	  </listitem>	  <listitem>	    <para>PMKSA caching</para>	  </listitem>	</itemizedlist>      </listitem>    </itemizedlist>  </refsect1>  <refsect1>    <title>Available Drivers</title>    <para>The available drivers to specify with the -D option are:</para>    <variablelist>      <varlistentry>	<term>hostap</term>	<listitem>	  <para>(default) Host AP driver (Intersil Prism2/2.5/3).  	  (this can also be used with Linuxant DriverLoader).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>hermes</term>	<listitem>	  <para>Agere Systems Inc. driver (Hermes-I/Hermes-II).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>madwifi</term>	<listitem>	  <para>MADWIFI 802.11 support (Atheros, etc.).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>atmel</term>	<listitem>	  <para>ATMEL AT76C5XXx (USB, PCMCIA).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>wext</term>	<listitem>	  <para>Linux wireless extensions (generic).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>ndiswrapper</term>	<listitem>	  <para>Linux ndiswrapper.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>broadcom</term>	<listitem>	  <para>Broadcom wl.o driver.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>ipw</term>	<listitem>	  <para>Intel ipw2100/2200 driver.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>wired</term>	<listitem>	  <para>wpa_supplicant wired Ethernet driver</para>	</listitem>      </varlistentry>      <varlistentry>	<term>bsd</term>	<listitem>	  <para>BSD 802.11 support (Atheros, etc.).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>ndis</term>	<listitem>	  <para>Windows NDIS driver.</para>	</listitem>      </varlistentry>    </variablelist>  </refsect1>  <refsect1>    <title>Command Line Options</title>    <variablelist>      <varlistentry>	<term>-B</term>	<listitem>	  <para>Run daemon in the background.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-i ifname</term>	<listitem>	  <para>Interface to listen on.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-c filename</term>	<listitem>	  <para>Path to configuration file.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-D driver</term>	<listitem>	  <para>Driver to use.  See the available options below.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-d</term>	<listitem>	  <para>Increase debugging verbosity (-dd even more).</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-K</term>	<listitem>	  <para>Include keys (passwords, etc.) in debug output.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-t</term>	<listitem>	  <para>Include timestamp in debug messages.</para>	</listitem>      </varlistentry>      <varlistentry>	<term>-e</term>	<listitem>	  <para>Use external IEEE 802.1X Supplicant (e.g.,          <command>xsupplicant</command>) (this disables the internal