source: networking/netprogs/wpa_supplicant.xml@ 48de78d

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;

  <!ENTITY wpa_supplicant-download-http
           "http://hostap.epitest.fi/releases/wpa_supplicant-&wpa_supplicant-version;.tar.gz">
  <!ENTITY wpa_supplicant-download-ftp  " ">
  <!ENTITY wpa_supplicant-md5sum        "8650f6aa23646ef634402552d0669640">
  <!ENTITY wpa_supplicant-size          "1.9 MB">
  <!ENTITY wpa_supplicant-buildsize     "16 MB">
  <!ENTITY wpa_supplicant-time          "0.1 SBU">
]>

<sect1 id="wpa_supplicant" xreflabel="wpa_supplicant-&wpa_supplicant-version;">
  <?dbhtml filename="wpa_supplicant.html"?>

  <sect1info>
    <othername>$LastChangedBy$</othername>
    <date>$Date$</date>
  </sect1info>

  <title>wpa_supplicant-&wpa_supplicant-version;</title>

  <indexterm zone="wpa_supplicant">
    <primary sortas="a-wpa_supplicant">wpa_supplicant</primary>
  </indexterm>

  <sect2 role="package">
    <title>Introduction to WPA Supplicant</title>

    <para>
      <application>WPA Supplicant</application> is a Wi-Fi Protected Access
      (WPA) client and IEEE 802.1X supplicant. It implements WPA key negotiation
      with a WPA Authenticator and Extensible Authentication Protocol (EAP)
      authentication with an Authentication Server. In addition, it controls the
      roaming and IEEE 802.11 authentication/association of the wireless LAN
      driver. This is useful for connecting to a password protected wireless
      access point.
    </para>

    &lfs72_checked;

    <bridgehead renderas="sect3">Package Information</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Download (HTTP): <ulink url="&wpa_supplicant-download-http;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download (FTP): <ulink url="&wpa_supplicant-download-ftp;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download MD5 sum: &wpa_supplicant-md5sum;
        </para>
      </listitem>
      <listitem>
        <para>
          Download size: &wpa_supplicant-size;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated disk space required: &wpa_supplicant-buildsize;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated build time: &wpa_supplicant-time;
        </para>
      </listitem>
    </itemizedlist>

    <bridgehead renderas="sect3">WPA Supplicant Dependencies</bridgehead>

    <bridgehead renderas="sect4">Recommended</bridgehead>
    <para role="recommended">
      <xref linkend="libnl"/> and
      <!-- From defconfig: WEXT is deprecated in the current Linux kernel
      version and no new functionality is added to it. nl80211-based
      interface is the new replacement for WEXT -->
      <xref linkend="openssl"/>
      <!-- For EAP-* Methods -->
    </para>

    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <xref linkend="dbus"/> and
      <xref linkend="libxml2"/>
      <!-- D-Bus and libxml2 are required for D-Bus Interface which
      NetworkManager uses.

      WPA Supplicant uses internal Linux specific implemenation
      for L2_PACKET, libpcap or libdnet are only there for portability
      with other OS'es. See README if you don't believe me. -->
    </para>

    <!-- TODO: Write instructions for building wpa_gui -->

    <para condition="html" role="usernotes">User Notes:
      <ulink url="&blfs-wiki;/wpa_supplicant"/>
    </para>
  </sect2>

  <sect2 role="kernel" id="wpa_supplicant-kernel">
    <title>Kernel Configuration</title>

    <para>
      Enable the following options in the kernel configuration
      and recompile the kernel if necessary:
    </para>

<screen><literal>[*] Networking support  --->
  [*]   Wireless  --->
    [*]   cfg80211 - wireless configuration API
    [*]     cfg80211 wireless extensions compatibility
    [*]   Generic IEEE 802.11 Networking Stack (mac80211)

Device Drivers  --->
  [*] Network device support  --->
    [*]   Wireless LAN  --->
</literal></screen>

    <para>
      Select the options that support your hardware:
      <command>lspci</command> from <xref linkend="pciutils"/> can be used to 
      view your hardware configuration.
    </para>

    <indexterm zone="wpa_supplicant wpa_supplicant-kernel">
      <primary sortas="d-wpa_supplicant">wpa_supplicant</primary>
    </indexterm>
  </sect2>

  <sect2 role="installation">
    <title>Installation of WPA Supplicant</title>

    <para>
      First you will need to create an initial configuration file for the
      build process. You can read <filename>wpa_supplicant/README</filename>
      and <filename>wpa_supplicant/defconfig</filename> for the explanation
      of the following options as well as other options that can be used.
      Create a build configuration file that should work for standard WiFi
      setups by running the following command:
    </para>

<screen><userinput>cat &gt; wpa_supplicant/.config &lt;&lt; "EOF"
CONFIG_BACKEND=file
CONFIG_CTRL_IFACE=y
CONFIG_DRIVER_NL80211=y
CONFIG_DRIVER_WEXT=y
CONFIG_DRIVER_WIRED=y
CONFIG_EAP_GTC=y
CONFIG_EAP_LEAP=y
CONFIG_EAP_MD5=y
CONFIG_EAP_MSCHAPV2=y
CONFIG_EAP_OTP=y
CONFIG_EAP_PEAP=y
CONFIG_EAP_TLS=y
CONFIG_EAP_TTLS=y
CONFIG_IEEE8021X_EAPOL=y
CONFIG_IPV6=y
CONFIG_LIBNL32=y
CONFIG_PEERKEY=y
CONFIG_PKCS12=y
CONFIG_READLINE=y
CONFIG_SMARTCARD=y
CONFIG_WPS=y
CFLAGS += -I/usr/include/libnl3
EOF</userinput></screen>

    <para>
      If you wish to use <application>WPA Supplicant</application> with
      <xref linkend="NetworkManager"/>, make sure that you have installed
      <xref linkend="dbus"/> and <xref linkend="libxml2"/>, then add
      following options to the <application>WPA Supplicant</application>
      build configuration file by running the following command:
    </para>

<screen><userinput>cat &gt;&gt; wpa_supplicant/.config &lt;&lt; "EOF"
CONFIG_CTRL_IFACE_DBUS=y
CONFIG_CTRL_IFACE_DBUS_NEW=y
CONFIG_CTRL_IFACE_DBUS_INTRO=y
EOF</userinput></screen>

    <para>
      Install <application>WPA Supplicant</application> by running the
      following commands:
    </para>

<screen><userinput>cd wpa_supplicant &amp;&amp;
make BINDIR=/sbin LIBDIR=/lib</userinput></screen>

    <para>
      This package does not come with a test suite.
    </para>

    <para>
      Now, as the <systemitem class="username">root</systemitem>
      user:
    </para>

<screen role="root"><userinput>install -v -m755 wpa_{cli,passphrase,supplicant} /sbin &amp;&amp;
install -v -m644 doc/docbook/wpa_supplicant.conf.5 /usr/share/man/man5 &amp;&amp;
install -v -m644 doc/docbook/wpa_{cli,passphrase,supplicant}.8 /usr/share/man/man8</userinput></screen>

    <para>
      If you have built <application>WPA Supplicant</application> with
      <application>D-Bus</application> support, you will need to install
      <application>D-Bus</application> configuration files. Install them
      by running the following commands as the
      <systemitem class="username">root</systemitem> user:
    </para>

<screen role="root"><userinput>install -v -m644 dbus/fi.{epitest.hostap.WPASupplicant,w1.wpa_supplicant1}.service \
                 /usr/share/dbus-1/system-services &amp;&amp;
install -v -m644 dbus/dbus-wpa_supplicant.conf /etc/dbus-1/system.d/wpa_supplicant.conf</userinput></screen>

    <note>
      <para>
        You will need to restart system <application>D-Bus</application> daemon
        before you can use <application>WPA Supplicant</application>
        <application>D-Bus</application> interface.
      </para>
    </note>

  </sect2>

  <sect2 role="configuration">
    <title>Configuring wpa_supplicant</title>

    <sect3 id="wpa_supplicant-config">
      <title>Config File</title>
      <para><filename>/etc/wpa_supplicant.conf</filename></para>

      <indexterm zone="wpa_supplicant wpa_supplicant-config">
        <primary
        sortas="e-etc-wpa_supplicant.conf">/etc/wpa_supplicant.conf</primary>
      </indexterm>
    </sect3>

    <sect3>
      <title>Configuration Information</title>

      <para>
        To connect to an access point that uses a password you need to put
        the pre-shared key in <filename>/etc/wpa_supplicant.conf</filename>. Use
        <command>wpa_passphrase</command> to generate this. SSID is the string
        that the access point/router transmits to identify itself. As the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root"><userinput>wpa_passphrase <replaceable>SSID</replaceable> <replaceable>SECRET_PASSWORD</replaceable> &gt; /etc/wpa_supplicant.conf</userinput></screen>

      <para>
        <filename>/etc/wpa_supplicant.conf</filename> can hold the details of
        several access points. When you run <command>wpa_supplicant</command>
        it will scan for the SSIDs it can see and choose the appropriate
        password to connect.
        </para>

      <para>
        If you want to connect to an access point that isn't password
        protected, put an entry like this in
        <filename>/etc/wpa_supplicant.conf</filename>. Replace
        "Some-SSID" with the SSID of the access point/router.
      </para>

<screen>network={
  ssid="<replaceable>Some-SSID</replaceable>"
  key_mgmt=NONE
}</screen>

      <para>
        There are many options that you could use to tweak how you connect
        to each access point. They are described in some detail in the
        <filename>wpa_supplicant/wpa_supplicant.conf</filename> file in the
        source tree.
      </para>

      <para>
        To use <command>wpa_cli</command> to control the running
        <command>>wpa_supplicant</command> daemon, add a control interface to
        <filename>/etc/wpa_supplicant.conf</filename> as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root"><userinput>echo ctrl_interface=/run/wpa_supplicant &gt;&gt; /etc/wpa_supplicant.conf</userinput></screen>
    </sect3>

    <sect3>
      <title>Connecting to an Access Point</title>

      <para>
        If your router/access point uses DHCP to allocate IP addresses you
        can install <xref linkend="dhcpcd"/> and use it to connect. As the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root"><userinput>wpa_supplicant -B -c/etc/wpa_supplicant.conf -iwlan0 -Dnl80211,wext
sleep 2 # let it settle
dhcpcd</userinput></screen>

      <para>
        Alternatively, you can use static addresses on your local network.
        This has the advantage that you can put the hostnames in
        <filename>/etc/hosts</filename>. Replace 192.168.1.6 with the static
        address you've chosen. Replace 192.168.1.1 with the local IP address of
        the access point/router. Run the following commands as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root"><userinput>ip addr add 192.168.1.6 dev wlan0
ip link set wlan0 up
wpa_supplicant -B -c/etc/wpa_supplicant.conf -iwlan0 -Dnl80211,wext
ip route add 192.168.1.1 dev wlan0
ip route add default via 192.168.1.1 dev wlan0</userinput></screen>

    </sect3>
  </sect2>

  <sect2 role="content">
    <title>Contents</title>

    <segmentedlist>
      <segtitle>Installed Programs</segtitle>
      <segtitle>Installed Libraries</segtitle>
      <segtitle>Installed Directories</segtitle>
      
      <seglistitem>
        <seg>wpa_supplicant, wpa_passphrase and wpa_cli</seg>
        <seg>none</seg>
        <seg>none</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="wpa_supplicant-prog">
        <term><command>wpa_supplicant</command></term>
        <listitem>
          <para>
            is a daemon that can connect to a password protected wireless
            access point.
          </para>
          <indexterm zone="wpa_supplicant wpa_supplicant-prog">
            <primary sortas="b-wpa_supplicant">wpa_supplicant</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="wpa_passphrase">
        <term><command>wpa_passphrase</command></term>
        <listitem>
          <para>
            takes an SSID and a password and generates a simple
            configuration that <command>wpa_supplicant</command> can
            understand.
          </para>
          <indexterm zone="wpa_supplicant wpa_passphrase">
            <primary sortas="b-wpa_passphrase">wpa_passphrase</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="wpa_cli">
        <term><command>wpa_cli</command></term>
        <listitem>
          <para>
            is a command line interface used to control a running
            <command>wpa_supplicant</command> daemon.
          </para>
          <indexterm zone="wpa_supplicant wpa_cli">
            <primary sortas="b-wpa_cli">wpa_cli</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>