php-doc-en/reference/exec/functions/escapeshellcmd.xml
Peter Cowburn 4d81bf2025 typofix "aly"
git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@325727 c90b9560-bf6c-de11-be94-00142212c4b1
2012-05-16 19:35:11 +00:00

123 lines
3.5 KiB
XML

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<!-- splitted from ./en/functions/exec.xml, last change in rev 1.2 -->
<refentry xml:id="function.escapeshellcmd" xmlns="http://docbook.org/ns/docbook">
<refnamediv>
<refname>escapeshellcmd</refname>
<refpurpose>Escape shell metacharacters</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>string</type><methodname>escapeshellcmd</methodname>
<methodparam><type>string</type><parameter>command</parameter></methodparam>
</methodsynopsis>
<para>
<function>escapeshellcmd</function> escapes any characters in a
string that might be used to trick a shell command into executing
arbitrary commands. This function should be used to make sure
that any data coming from user input is escaped before this data
is passed to the <function>exec</function> or
<function>system</function> functions, or to the <link
linkend="language.operators.execution">backtick
operator</link>.
</para>
<para>
Following characters are preceded by a backslash:
<literal>#&amp;;`|*?~&lt;&gt;^()[]{}$\</literal>, <literal>\x0A</literal>
and <literal>\xFF</literal>. <literal>'</literal> and <literal>"</literal>
are escaped only if they are not paired. In Windows, all these characters
plus <literal>%</literal> are replaced by a space instead.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
<varlistentry>
<term><parameter>command</parameter></term>
<listitem>
<para>
The command that will be escaped.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
The escaped string.
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title><function>escapeshellcmd</function> example</title>
<programlisting role="php">
<![CDATA[
<?php
// We allow arbitrary number of arguments intentionally here.
$command = './configure '.$_POST['configure_options'];
$escaped_command = escapeshellcmd($command);
system($escaped_command);
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="notes">
<warning xmlns="http://docbook.org/ns/docbook">
<para>
<function>escapeshellcmd</function> should be used on the whole
command string, and it still allows the attacker to pass
arbitrary number of arguments. For escaping a single argument
<function>escapeshellarg</function> should be used instead.
</para>
</warning>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>escapeshellarg</function></member>
<member><function>exec</function></member>
<member><function>popen</function></member>
<member><function>system</function></member>
<member><link linkend="language.operators.execution">backtick operator</link></member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->