source: networking/netprogs/wpa_supplicant.xml@ 7c59035

<?xml version="1.0" encoding="UTF-8"?>
<!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
           "https://w1.fi/releases/wpa_supplicant-&wpa_supplicant-version;.tar.gz">
  <!ENTITY wpa_supplicant-download-ftp  " ">
  <!ENTITY wpa_supplicant-md5sum        "72a4a00eddb7a499a58113c3361ab094">
  <!ENTITY wpa_supplicant-size          "3.7 MB">
  <!ENTITY wpa_supplicant-buildsize     "35 MB">
  <!ENTITY wpa_supplicant-time          "0.3 SBU">
]>

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


  <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>

    &lfs122_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">Additional Downloads</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Required patch:
          <ulink url="&patch-root;/wpa_supplicant-&wpa_supplicant-version;-security_fix-1.patch"/>
        </para>
      </listitem>
    </itemizedlist>
-->
    <bridgehead renderas="sect3">WPA Supplicant Dependencies</bridgehead>

    <bridgehead renderas="sect4">Required (Runtime)</bridgehead>
    <para role="nodump">
      <xref linkend="wireless-kernel"/>
    </para>

    <bridgehead renderas="sect4">Recommended</bridgehead>
    <para role="recommended">
      <xref linkend="desktop-file-utils"/> (for running
        <command>update-desktop-database</command>) and
      <xref linkend="libnl"/>
    </para>

    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <phrase revision="sysv"><xref linkend="dbus"/> and</phrase>
      <xref linkend="libxml2"/>
    </para>


  </sect2>

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

    <para>
      To use <application>wpa_supplicant</application>, the kernel must have
      the appropriate drivers and other support available.  Read
      <xref linkend='wireless-kernel'/> for details.
    </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"
<literal>CONFIG_BACKEND=file
CONFIG_CTRL_IFACE=y
CONFIG_DEBUG_FILE=y
CONFIG_DEBUG_SYSLOG=y
CONFIG_DEBUG_SYSLOG_FACILITY=LOG_DAEMON
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</literal>
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 the
      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"
<literal>CONFIG_CTRL_IFACE_DBUS=y
CONFIG_CTRL_IFACE_DBUS_NEW=y
CONFIG_CTRL_IFACE_DBUS_INTRO=y</literal>
EOF</userinput></screen>

<!-- Fixed in version 2.11
    <para>
      Next, patch a security vulnerability that occurs when connecting to some
      networks:
      <!- - CVE-2023-52160, see Ticket #19304. - ->
    </para>

<screen><userinput>patch -Np1 -i ../wpa_supplicant-&wpa_supplicant-version;-security_fix-1.patch</userinput></screen>
-->
    <para>
      Install <application>WPA Supplicant</application> by running the
      following commands:
    </para>

<screen><userinput>cd wpa_supplicant &amp;&amp;
make BINDIR=/usr/sbin LIBDIR=/usr/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} /usr/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 revision="systemd">
      Install the <application>systemd</application> support files by
      running the following command as the <systemitem
      class="username">root</systemitem> user:
    </para>

<screen role="root" revision="systemd"><userinput>install -v -m644 systemd/*.service /usr/lib/systemd/system/</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.w1.wpa_supplicant1.service \
                 /usr/share/dbus-1/system-services/ &amp;&amp;
install -v -d -m755 /etc/dbus-1/system.d &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 the system <application>D-Bus</application> daemon
        before you can use the <application>WPA Supplicant</application>
        <application>D-Bus</application> interface.
      </para>
    </note>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="../../xincludes/update-desktop-database.xml"/>

  </sect2>

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

    <important>
      <para>
        If you are using WPA Supplicant with
        <xref linkend='NetworkManager'/> (or anything communicating with
        WPA Supplicant via D-Bus), this section should be skipped.  Running
        a D-Bus connected WPA Supplicant instance and another WPA supplicant
        instance configured following this section simultaneously can cause
        subtle issues.
      </para>
    </important>

    <sect3 id="wpa_supplicant-config">
      <title>Config File</title>

      <para revision="sysv">
        <filename>/etc/sysconfig/wpa_supplicant-*.conf</filename>
      </para>

      <para revision="systemd">
        <filename>/etc/wpa_supplicant/wpa_supplicant-*.conf</filename>
      </para>

      <indexterm zone="wpa_supplicant wpa_supplicant-config" revision="sysv">
        <primary
        sortas="e-etc-sysconfig-wpa_supplicant-star.conf">/etc/sysconfig/wpa_supplicant-*.conf</primary>
      </indexterm>

      <indexterm zone="wpa_supplicant wpa_supplicant-config" revision="systemd">
        <primary
        sortas="e-etc-wpa_supplicant-wpa_supplicant-star.conf">/etc/wpa_supplicant/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
        <phrase revision="sysv">
          <filename>
 /etc/sysconfig/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</filename>.
        </phrase>
        <phrase revision="systemd">
          <filename>
 /etc/wpa_supplicant/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</filename>.
        </phrase>
        SSID is the string that the access point/router transmits to
        identify itself. Run the following command as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="nodump" revision="sysv"><userinput>wpa_passphrase <replaceable>SSID</replaceable> <replaceable>SECRET_PASSWORD</replaceable> &gt; /etc/sysconfig/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</userinput></screen>

<screen role="nodump" revision="systemd"><userinput>install -v -dm755 /etc/wpa_supplicant &amp;&amp;
wpa_passphrase <replaceable>SSID</replaceable> <replaceable>SECRET_PASSWORD</replaceable> &gt; /etc/wpa_supplicant/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</userinput></screen>

      <para>
        <phrase revision="sysv">
          <filename>
            /etc/sysconfig/wpa_supplicant-<replaceable>wifi0</replaceable>.conf
          </filename>
        </phrase>
        <phrase revision="systemd">
          <filename>
            /etc/wpa_supplicant/wpa_supplicant-<replaceable>wifi0</replaceable>.conf
          </filename>
        </phrase>
        can hold the details of several access points. When
        <command>wpa_supplicant</command> is started, 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
        <phrase revision="sysv">
          <filename>
/etc/sysconfig/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</filename>.
        </phrase>
        <phrase revision="systemd">
          <filename>
/etc/wpa_supplicant/wpa_supplicant-<replaceable>wifi0</replaceable>.conf</filename>.
        </phrase>
        Replace "Some-SSID" with the SSID of the access point/router.
      </para>

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

      <para>
        Connecting to a new access point that is not in the configuration
        file can be accomplished manually via the command line, but it
        must be done via a privileged user. To do that, add the following to
        the configuration file:
      </para>

<screen>ctrl_interface=DIR=/run/wpa_supplicant GROUP=&lt;privileged group&gt;
update_config=1</screen>

      <para>
        Replace the &lt;privileged group&gt; above with a system group where
        members have the ability to connect to a wireless access point.
      </para>

      <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>

    </sect3>

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

      <para id="wpa-service" revision="sysv">
        If you want to configure network interfaces at boot using
        <command>wpa_supplicant</command>, you need to install the
        <filename>/lib/services/wpa</filename> script
        included in <xref linkend="bootscripts"/> package:
      </para>

<screen role="root" revision="sysv"><userinput>make install-service-wpa</userinput></screen>

      <indexterm zone="wpa_supplicant wpa-service" revision="sysv">
        <primary sortas="f-wpa">wpa</primary>
      </indexterm>

      <para revision="sysv">
        If your router/access point uses DHCP to allocate IP addresses, you
        can install <xref linkend="dhcpcd" role="nodep"/> and use it to
        automatically obtain network addresses. Create the
        <filename>/etc/sysconfig/ifconfig-<replaceable>wifi0</replaceable>
        </filename> by running the following command as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root" revision="sysv"><userinput>cat &gt; /etc/sysconfig/ifconfig.<replaceable>wifi0</replaceable> &lt;&lt; "EOF"
<literal>ONBOOT="yes"
IFACE="<replaceable>wlan0</replaceable>"
SERVICE="wpa"

# Additional arguments to wpa_supplicant
WPA_ARGS=""

WPA_SERVICE="dhcpcd"
DHCP_START="-b -q <replaceable>&lt;insert appropriate start options here&gt;</replaceable>"
DHCP_STOP="-k <replaceable>&lt;insert additional stop options here&gt;</replaceable>"</literal>
EOF</userinput></screen>

      <para revision="sysv">
        Alternatively, if you use static addresses on your local network,
        then create the
        <filename>/etc/sysconfig/ifconfig-<replaceable>wifi0</replaceable>
        </filename> by running the following command as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root" revision="sysv"><userinput>cat &gt; /etc/sysconfig/ifconfig.<replaceable>wifi0</replaceable> &lt;&lt; "EOF"
<literal>ONBOOT="yes"
IFACE="<replaceable>wlan0</replaceable>"
SERVICE="wpa"

# Additional arguments to wpa_supplicant
WPA_ARGS=""

WPA_SERVICE="ipv4-static"
IP="192.168.1.1"
GATEWAY="192.168.1.2"
PREFIX="24"
BROADCAST="192.168.1.255"</literal>
EOF</userinput></screen>

      <para revision="systemd">
        There are 3 types of <application>systemd</application> units
        that were installed:
      </para>

      <itemizedlist spacing="compact" revision="systemd">
        <listitem>
          <para>
            wpa_supplicant@.service
          </para>
        </listitem>
        <listitem>
          <para>
            wpa_supplicant-nl80211@.service
          </para>
        </listitem>
        <listitem>
          <para>
            wpa_supplicant-wired@.service
          </para>
        </listitem>
      </itemizedlist>

      <para revision="systemd">
        The only difference between 3 of them is what driver
        is used for connecting (-D option). The first one uses
        the default driver, the second one uses the nl80211
        driver and the third one uses the wired driver.
      </para>

      <para>
        You can connect to the wireless access point by
        running the following command as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root" revision="sysv"><userinput>ifup <replaceable>wifi0</replaceable></userinput></screen>

      <para revision="sysv">
        Replace <replaceable>wlan0</replaceable> with the correct
        wireless interface and <replaceable>wifi0</replaceable>
        with desired name for the configuration file. Please note
        that <filename>wpa_supplicant-*.conf</filename> and
        <filename>ifconfig.*</filename> configuration files need
        to have identical names, ie both contain
        <replaceable>wifi0</replaceable> in their name.
      </para>

<screen role="root" revision="systemd"><userinput>systemctl start wpa_supplicant@<replaceable>wlan0</replaceable></userinput></screen>

      <para revision="systemd">
        To connect to the wireless access point at
        boot, simply enable the appropriate
        <command>wpa_supplicant</command> service
        by running the following command as the
        <systemitem class="username">root</systemitem> user:
      </para>

<screen role="root" revision="systemd"><userinput>systemctl enable wpa_supplicant@<replaceable>wlan0</replaceable></userinput></screen>

      <para revision="systemd">
        Depending on your setup, you can replace the
        <filename>wpa_supplicant@.service</filename>
        with any other listed above.
      </para>

      <para revision="systemd">
        To assign a network address to your wireless interface, consult the
        <ulink url="&lfs-root;/chapter09/network.html">General Network Configuration</ulink>
        page in LFS.
      </para>

    </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>