docs/manual/mod/mod_proxy_ftp.xml

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<modulesynopsis metafile="mod_proxy_ftp.xml.meta">

<name>mod_proxy_ftp</name>
<description>FTP support module for
<module>mod_proxy</module></description>
<status>Extension</status>
<sourcefile>mod_proxy_ftp.c</sourcefile>
<identifier>proxy_ftp_module</identifier>

<summary>
    <p>This module <em>requires</em> the service of <module
    >mod_proxy</module>. It provides support for the proxying
    FTP sites.  Note that FTP support is currently limited to
    the GET method.</p>

    <p>Thus, in order to get the ability of handling FTP proxy requests,
    <module>mod_proxy</module> and <module>mod_proxy_ftp</module>
    have to be present in the server.</p>

    <note type="warning"><title>Warning</title>
      <p>Do not enable proxying until you have <a
      href="mod_proxy.html#access">secured your server</a>. Open proxy
      servers are dangerous both to your network and to the Internet at
      large.</p>
    </note>
</summary>
<seealso><module>mod_proxy</module></seealso>

    <section id="mimetypes"><title>Why doesn't file type <var>xxx</var>
    download via FTP?</title>
      <p>You probably don't have that particular file type defined as
      <code>application/octet-stream</code> in your proxy's mime.types
      configuration file. A useful line can be:</p>

      <example>
<pre>application/octet-stream   bin dms lha lzh exe class tgz taz</pre>
      </example>
      <p>Alternatively you may prefer to use the <directive module="core">ForceType</directive>
      directive to default everything to binary:</p>
      <example>
        <highlight language="config">
ForceType application/octet-stream
        </highlight>
      </example>
    </section> <!-- /mimetypes -->

    <section id="type"><title>How can I force an FTP ASCII download of
    file <var>xxx</var>?</title>
      <p>In the rare situation where you must download a specific file using the
      FTP <code>ASCII</code> transfer method (while the default transfer is in
      <code>binary</code> mode), you can override <module>mod_proxy</module>'s
      default by suffixing the request with <code>;type=a</code> to force an
      ASCII transfer. (FTP Directory listings are always executed in ASCII mode,
      however.)</p>
    </section> <!-- /type -->

    <section id="ftpnonget"><title>How can I do FTP upload?</title>
    <p>Currently, only GET is supported for FTP in <module>mod_proxy</module>.  You can
    of course use HTTP upload (POST or PUT) through an Apache proxy.</p>
    </section>

    <section id="percent2fhck"><title>How can I access FTP files outside
    of my home directory?</title>
      <p>An FTP URI is interpreted relative to the home directory of the user
      who is logging in. Alas, to reach higher directory levels you cannot
      use /../, as the dots are interpreted by the browser and not actually
      sent to the FTP server. To address this problem, the so called <dfn>Squid
      %2f hack</dfn> was implemented in the Apache FTP proxy; it is a
      solution which is also used by other popular proxy servers like the <a
      href="http://www.squid-cache.org/">Squid Proxy Cache</a>. By
      prepending <code>/%2f</code> to the path of your request, you can make
      such a proxy change the FTP starting directory to <code>/</code> (instead
      of the home directory). For example, to retrieve the file
      <code>/etc/motd</code>, you would use the URL:</p>

      <example>
        ftp://<var>user</var>@<var>host</var>/%2f/etc/motd
      </example>
    </section> <!-- /percent2fhck -->

    <section id="ftppass"><title>How can I hide the FTP cleartext password
    in my browser's URL line?</title>
      <p>To log in to an FTP server by username and password, Apache uses
      different strategies. In absence of a user name and password in the URL
      altogether, Apache sends an anonymous login to the FTP server,
      <em>i.e.</em>,</p>

      <example>
        user: anonymous<br />
        password: apache-proxy@
      </example>

      <p>This works for all popular FTP servers which are configured for
      anonymous access.</p>

      <p>For a personal login with a specific username, you can embed the user
      name into the URL, like in:</p>

      <example>
        ftp://<var>username</var>@<var>host</var>/myfile
      </example>

      <note><title>HttpProtocolOptions</title>
        <p>By default, <directive module="core"
        >HttpProtocolOptions</directive> is set to <code>Strict</code>,
        which rejects URLs containing userinfo (username or password)
        per RFC 7230.  To use credentials in FTP URLs, you must set
        <code>HttpProtocolOptions Unsafe</code>.</p>
      </note>

      <p>If the FTP server asks for a password when given this username (which
      it should), then Apache will reply with a <code>401</code> (Authorization
      required) response, which causes the Browser to pop up the
      username/password dialog. Upon entering the password, the connection
      attempt is retried, and if successful, the requested resource is
      presented. The advantage of this procedure is that your browser does not
      display the password in cleartext (which it would if you had used</p>

      <example>
        ftp://<var>username</var>:<var>password</var>@<var>host</var>/myfile
      </example>

      <p>in the first place).</p>

      <note><title>Note</title>
        <p>The password which is transmitted in such a way is not encrypted on
        its way. It travels between your browser and the Apache proxy server in
        a base64-encoded cleartext string, and between the Apache proxy and the
        FTP server as plaintext. You should therefore think twice before
        accessing your FTP server via HTTP (or before accessing your personal
        files via FTP at all!) When using insecure channels, an eavesdropper
        might intercept your password on its way.</p>
      </note>
    </section> <!-- /ftppass -->

    <section id="wildcard"><title>Why do I get a file listing when I expected
        a file to be downloaded?</title>
      <p>In order to allow both browsing the directories on an FTP server and
        downloading files, Apache looks at the request URL.  If it looks like
        a directory, or contains wildcard characters ("*?[{~"), then it
        guesses that a listing is wanted instead of a download.</p>
      <p>You can disable the special handling of names with wildcard characters.
        See the <directive module="mod_proxy_ftp">ProxyFtpListOnWildcard</directive> directive.
      </p>
    </section> <!-- /wildcard -->

<directivesynopsis>
<name>ProxyFtpListOnWildcard</name>
<description>Whether wildcards in requested filenames trigger a file listing</description>
<syntax>ProxyFtpListOnWildcard on|off</syntax>
<default>ProxyFtpListOnWildcard on</default>
<contextlist><context>server config</context><context>virtual host</context>
  <context>directory</context></contextlist>
<compatibility>Available in Apache 2.3.3 and later</compatibility>

<usage>
  <p>The <directive>ProxyFtpListOnWildcard</directive> directive
    controls whether wildcard characters ("*?[{~") in requested
    filenames cause <module>mod_proxy_ftp</module> to return a listing
    of files instead of downloading a file.  By default (value on),
    they do.</p>
    <p>Set to "off" to allow downloading files even if they
    have wildcard characters in their names.</p>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>ProxyFtpEscapeWildcards</name>
<description>Whether wildcards in requested filenames are escaped when sent to the FTP server</description>
<syntax>ProxyFtpEscapeWildcards on|off</syntax>
<default>ProxyFtpEscapeWildcards on</default>
<contextlist><context>server config</context><context>virtual host</context>
  <context>directory</context></contextlist>
<compatibility>Available in Apache 2.3.3 and later</compatibility>

<usage>
  <p>The <directive>ProxyFtpEscapeWildcards</directive> directive
    controls whether wildcard characters ("*?[{~") in requested
    filenames are escaped with backslash before sending them to the
    FTP server.  That is the default behavior, but many FTP servers
    don't know about the escaping and try to serve the literal filenames
    they were sent, including the backslashes in the names.</p>
    <p>Set to "off" to allow downloading files with wildcards
    in their names from FTP servers that don't understand wildcard
    escaping.</p>
</usage>
</directivesynopsis>

<directivesynopsis>
<name>ProxyFtpDirCharset</name>
<description>Define the character set for proxied FTP listings</description>
<syntax>ProxyFtpDirCharset <var>character_set</var></syntax>
<default>ProxyFtpDirCharset ISO-8859-1</default>
<contextlist><context>server config</context><context>virtual host</context>
<context>directory</context></contextlist>
<compatibility>Moved from <module>mod_proxy</module> in Apache 2.3.5.</compatibility>

<usage>
    <p>The <directive>ProxyFtpDirCharset</directive> directive defines the
    character set to be set for FTP directory listings in HTML generated by
    <module>mod_proxy_ftp</module>.</p>
</usage>
</directivesynopsis>

</modulesynopsis>