source: server/major/vsftpd.xml

<?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 vsftpd-download-http "https://security.appspot.com/downloads/vsftpd-&vsftpd-version;.tar.gz">
  <!ENTITY vsftpd-download-ftp  " ">
  <!ENTITY vsftpd-md5sum        "efbf362a65bec771bc15ad311f5a982e">
  <!ENTITY vsftpd-size          "210 KB">
  <!ENTITY vsftpd-buildsize     "1.9 MB">
  <!ENTITY vsftpd-time          "less than 0.1 SBU">
  <!ENTITY vsftpd-empty         "/usr/share/vsftpd/empty">
]>

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


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

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

  <sect2 role="package">
    <title>Introduction to vsftpd</title>

    <para>
      The <application>vsftpd</application> package contains a very
      secure and very small FTP daemon. This is useful for serving files
      over a network.
    </para>

    &lfs121_checked;

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

    <bridgehead renderas="sect3">vsftpd Dependencies</bridgehead>

    <bridgehead renderas="sect4">Required</bridgehead>
    <para role="required">
      <xref linkend="libnsl"/>
    </para>

    <bridgehead renderas="sect4">Recommended</bridgehead>
    <para role="recommended">
      <xref linkend="linux-pam"/>
    </para>

    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <xref linkend="libcap-pam"/>
    </para>

  </sect2>

  <sect2 role="installation">
    <title>Installation of vsftpd</title>

    <para>
      For security reasons, running <application>vsftpd</application>
      as an unprivileged user and group is encouraged. Also, a user should be
      created to map anonymous users. As the <systemitem
      class="username">root</systemitem> user, create the needed directories,
      users, and groups with the following commands:
    </para>

<screen role="root"><userinput>install -v -d -m 0755 &vsftpd-empty; &amp;&amp;
install -v -d -m 0755 /home/ftp               &amp;&amp;
groupadd -g 47 vsftpd                         &amp;&amp;
groupadd -g 45 ftp                            &amp;&amp;

useradd -c "vsftpd User"  -d /dev/null -g vsftpd -s /bin/false -u 47 vsftpd &amp;&amp;
useradd -c anonymous_user -d /home/ftp -g ftp    -s /bin/false -u 45 ftp</userinput></screen>

    <para>
      Gcc-10 and later flags an error for an implicit type cast. Make it
      explicit:
    </para>

<screen><userinput>sed -e "s/kVSFSysStrOpenUnknown;/(enum EVSFSysUtilOpenMode)&amp;/" -i sysstr.c</userinput></screen>

    <para>
      Build <application>vsftpd</application> as an unprivileged user
      using the following command:
    </para>

<screen><userinput>make</userinput></screen>

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

    <para>
      Once again, become the <systemitem class="username">root</systemitem>
      user and install <application>vsftpd</application> with the following
      commands:
    </para>

<screen role="root"><userinput>install -v -m 755 vsftpd        /usr/sbin/vsftpd    &amp;&amp;
install -v -m 644 vsftpd.8      /usr/share/man/man8 &amp;&amp;
install -v -m 644 vsftpd.conf.5 /usr/share/man/man5 &amp;&amp;
install -v -m 644 vsftpd.conf   /etc</userinput></screen>

  </sect2>

  <sect2 role="commands">
    <title>Command Explanations</title>

    <para>
      <command>install -v -d ...</command>: This creates the
      directory that anonymous users will use (<filename
      class='directory'>/home/ftp</filename>)
      and the directory the daemon will chroot into
      (<filename class='directory'>&vsftpd-empty;</filename>).
    </para>

    <note>
      <para>
        <filename class="directory">/home/ftp</filename> should not be
        owned by the user <systemitem class="username">vsftpd</systemitem>,
        or the user <systemitem class="username">ftp</systemitem>.
      </para>
    </note>

    <para>
      <command>echo "#define VSF_BUILD_TCPWRAPPERS" >>builddefs.h</command>:
      Use this prior to <command>make</command> to add support for
      <application>tcpwrappers</application>.
    </para>

    <para>
      <command>echo "#define VSF_BUILD_SSL" >>builddefs.h</command>:
      Use this prior to <command>make</command> to add support for SSL.
    </para>

    <para>
      <command>install -v -m ...</command>:
      The <filename>Makefile</filename> uses non-standard installation paths.
      These commands install the files in
      <filename class='directory'>/usr</filename> and
      <filename class='directory'>/etc</filename>.
    </para>

  </sect2>

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

    <sect3 id="vsftpd-config">
      <title>Config Files</title>

      <para>
        <filename>/etc/vsftpd.conf</filename>
      </para>

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

    </sect3>

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

      <para>
        <application>vsftpd</application> comes with a basic
        anonymous-only configuration file that was copied to
        <filename class='directory'>/etc</filename> above. While still as
        <systemitem class="username">root</systemitem>, this file should be
        modified because it is now recommended to run <command>vsftpd</command>
        in standalone mode. Also, you
        should specify the privilege separation user created above. Finally,
        you should specify the <command>chroot</command> directory.
        <command>man vsftpd.conf</command> will give you all the details.
      </para>

<screen role="root"><userinput>cat &gt;&gt; /etc/vsftpd.conf &lt;&lt; "EOF"
<literal>background=YES
nopriv_user=vsftpd
secure_chroot_dir=&vsftpd-empty;</literal>
EOF</userinput></screen>

      <!-- recheck this issue when vsftpd is updated -->
<!-- Aug'23:  Cannot see any difference in behavior of vsftpd
              when that option is set or not

      <para>
        The vsftpd daemon uses seccomp to improve security by default.
        But it's known to cause vsftpd unable to handle ftp
        <literal>LIST</literal> command with recent kernel versions.  Append
        a line to <filename>/etc/vsftpd.conf</filename> (as the
        <systemitem class="username">root</systemitem> user) to disable
        seccomp and workaround this issue:
      </para>

<screen role="root"><userinput>cat &gt;&gt; /etc/vsftpd.conf &lt;&lt; "EOF"
<literal>seccomp_sandbox=NO</literal>
EOF</userinput></screen>
-->
      <para>
        To enable local logins, append the following to the
        <filename>/etc/vsftpd.conf</filename> file (as the
        <systemitem class="username">root</systemitem> user):
      </para>

<screen role="root"><userinput>cat &gt;&gt; /etc/vsftpd.conf &lt;&lt; "EOF"
<literal>local_enable=YES</literal>
EOF</userinput></screen>

      <para>
        In addition, if using <application>Linux-PAM</application> and
        <application>vsftpd</application> with local user logins, you will need
        a <application>Linux-PAM</application> configuration file. As the
        <systemitem class="username">root</systemitem> user, create the
        <filename>/etc/pam.d/vsftpd</filename> file, and add the needed
        configuration changes for <application>Linux-PAM</application> session
        support using the following commands:
      </para>

<screen role="root"><userinput>cat &gt; /etc/pam.d/vsftpd &lt;&lt; "EOF" &amp;&amp;
<literal># Begin /etc/pam.d/vsftpd
auth       required     /lib/security/pam_listfile.so item=user sense=deny \
                                                      file=/etc/ftpusers \
                                                      onerr=succeed
auth       required     pam_shells.so
auth       include      system-auth
account    include      system-account
session    include      system-session</literal>
EOF

cat &gt;&gt; /etc/vsftpd.conf &lt;&lt; "EOF"
<literal>session_support=YES
pam_service_name=vsftpd</literal>
EOF</userinput></screen>

    </sect3>

    <sect3  id="vsftpd-init">
      <title><phrase revision="sysv">Boot Script</phrase>
             <phrase revision="systemd">Systemd Unit</phrase></title>

      <para>
        Install the
        <phrase revision="sysv"><filename>/etc/rc.d/init.d/vsftpd</filename>
        init script</phrase>
        <phrase revision="systemd"><filename>vsftpd.service</filename>
        unit</phrase> included in the
        <xref linkend="bootscripts" revision="sysv"/>
        <xref linkend="systemd-units" revision="systemd"/> package:
      </para>

<screen role="root"><userinput>make install-vsftpd</userinput></screen>

    </sect3>

  </sect2>

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

    <segmentedlist>
      <segtitle>Installed Program</segtitle>
      <segtitle>Installed Libraries</segtitle>
      <segtitle>Installed Directories</segtitle>

      <seglistitem>
        <seg>vsftpd</seg>
        <seg>None</seg>
        <seg>/usr/share/vsftpd, /home/ftp</seg>
      </seglistitem>
    </segmentedlist>

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

      <varlistentry id="vsftpd-prog">
        <term><command>vsftpd</command></term>
        <listitem>
          <para>
            is the FTP daemon
          </para>
          <indexterm zone="vsftpd vsftpd-prog">
            <primary sortas="b-vsftpd">vsftpd</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>