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<?xml version="1.0" encoding="iso-8859-2"?>
<!-- EN-Revision: 1.18 Maintainer: luk Status: ready -->
<chapter id="features.safe-mode">
<title>Bezpen reim</title>
<para>
Bezpen reim PHP je pokus o een bezpenosti sdlench server.
Je architekturln nekorektn pokouet se eit tento problm na
rovni PHP, ale protoe een na rovni webovskho serveru a operanho
systmu nejsou pli realistick, mnoho lid, zvlat ISP, pouv
nyn bezpen reim.
</para>
<para>
Konfiguran direktivy, kter ovldaj bezpen reim:
<programlisting role="ini">
<![CDATA[
safe_mode = Off
open_basedir =
safe_mode_exec_dir =
safe_mode_allowed_env_vars = PHP_
safe_mode_protected_env_vars = LD_LIBRARY_PATH
disable_functions =
]]>
</programlisting>
</para>
<para>
Pokud je <link linkend="ini.safe-mode">safe_mode</link> zapnut, PHP
kontroluje, je-li vlastnk bcho skriptu vlastnkem souboru, s nm
se m manipulovat. Napklad:
<programlisting role="ls">
<![CDATA[
-rw-rw-r-- 1 rasmus rasmus 33 Jul 1 19:20 script.php
-rw-r--r-- 1 root root 1116 May 26 18:01 /etc/passwd
]]>
</programlisting>
Sputn skriptu script.php
<programlisting role="php">
<![CDATA[
<?php
readfile('/etc/passwd');
?>
]]>
</programlisting>
bude mt v bezpenm reimu za vsledek tuto chybu:
<screen>
<![CDATA[
Warning: SAFE MODE Restriction in effect. The script whose uid is 500 is not
allowed to access /etc/passwd owned by uid 0 in /docroot/script.php on line 2
]]>
</screen>
</para>
<para>
Pokud namsto <link linkend="ini.safe-mode">safe_mode</link> nastavte
adres <link linkend="ini.open-basedir">open_basedir</link>, potom
vechny operace se soubory budou omezeny pod specifikovan adres.
Napklad (pklad Apache httpd.conf):
<programlisting role="ini">
<![CDATA[
<Directory /docroot>
php_admin_value open_basedir /docroot
</Directory>
]]>
</programlisting>
Kdy spustte tent soubor script.php s timto nastavenm
<link linkend="ini.open-basedir">open_basedir</link>, dostanete tento
vsledek:
<screen>
<![CDATA[
Warning: open_basedir restriction in effect. File is in wrong directory in
/docroot/script.php on line 2
]]>
</screen>
</para>
<para>
Mete tak vypnout jednotliv funkce. Pokud pidme toto do souboru
php.ini:
<programlisting role="ini">
<![CDATA[
disable_functions readfile,system
]]>
</programlisting>
zskme takovto vstup:
<screen>
<![CDATA[
Warning: readfile() has been disabled for security reasons in
/docroot/script.php on line 2
]]>
</screen>
</para>
<sect1 id="features.safe-mode.functions">
<title>Funkce omezen/deaktivovan v bezpenm reimu</title>
<para>
Toto je pravdpodobn nepln a mon nesprvn pehled funkc
omezench v
<link linkend="features.safe-mode">bezpenm reimu</link>.
<!-- TODO: add ¬e.sm.*; to the functions mentioned here.
That entity should link to this section -->
<table>
<title>Funkce omezen v bezpenm reimu</title>
<tgroup cols="2">
<thead>
<row>
<entry>Funkce</entry>
<entry>Omezen</entry>
</row>
</thead>
<tbody>
<row>
<entry><function>dbmopen</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>dbase_open</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>filepro</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>filepro_rowcount</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>filepro_retrieve</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>ifx_*</function></entry>
<entry>sql_safe_mode restrictions, (!= safe mode)</entry>
<!-- TODO: more info on sql-safe-mode -->
</row>
<row>
<entry><function>ingres_*</function></entry>
<entry>sql_safe_mode restrictions, (!= safe mode)</entry>
<!-- TODO: more info on sql-safe-mode -->
</row>
<row>
<entry><function>mysql_*</function></entry>
<entry>sql_safe_mode restrictions, (!= safe mode)</entry>
<!-- TODO: more info on sql-safe-mode -->
</row>
<row>
<entry><function>pg_loimport</function></entry>
<entry>&sm.uidcheck;</entry>
<!-- source TODO: there is no PHP-warning for that safe-mode-restriction -->
</row>
<row>
<entry><function>posix_mkfifo</function></entry>
<entry>&sm.uidcheck.dir;</entry>
</row>
<row>
<entry><function>putenv</function></entry>
<entry>Obeys the safe_mode_protected_env_vars and
safe_mode_allowed_env_vars ini-directives. Viz tak dokumentaci
<function>putenv</function></entry>
<!-- TODO: document those directives in chapters/config.xml -->
</row>
<row>
<entry><function>move_uploaded_file</function></entry>
<entry>&sm.uidcheck; <!-- TODO: check this --></entry>
</row>
<!-- TODO: from here on, add warning to the function itself -->
<row>
<entry><function>chdir</function></entry>
<entry>&sm.uidcheck.dir;</entry>
</row>
<row>
<entry><function>dl</function></entry>
<entry>&sm.disabled;</entry>
</row>
<row>
<entry><link linkend="language.operators.execution">backtick opertor</link></entry>
<entry>&sm.disabled;</entry>
</row>
<row>
<entry><function>shell_exec</function> (funkn ekvivalent backticks)</entry>
<entry>&sm.disabled;</entry>
</row>
<row>
<entry><function>exec</function></entry>
<entry>Mete spoutt programy pouze uvnit adrese <link
linkend="ini.safe-mode-exec-dir">safe_mode_exec_dir</link>.
Z praktickch dvod nen momentln mon mt v cest k souboru
s programem komponenty <literal>..</literal>.</entry>
</row>
<row>
<entry><function>system</function></entry>
<entry>Mete spoutt programy pouze uvnit adrese <link
linkend="ini.safe-mode-exec-dir">safe_mode_exec_dir</link>.
Z praktickch dvod nen momentln mon mt v cest k souboru
s programem komponenty <literal>..</literal>.</entry>
</row>
<row>
<entry><function>passthru</function></entry>
<entry>Mete spoutt programy pouze uvnit adrese <link
linkend="ini.safe-mode-exec-dir">safe_mode_exec_dir</link>.
Z praktickch dvod nen momentln mon mt v cest k souboru
s programem komponenty <literal>..</literal>.</entry>
</row>
<row>
<entry><function>popen</function></entry>
<entry>Mete spoutt programy pouze uvnit adrese <link
linkend="ini.safe-mode-exec-dir">safe_mode_exec_dir</link>.
Z praktickch dvod nen momentln mon mt v cest k souboru
s programem komponenty <literal>..</literal>.</entry>
<!-- TODO: not sure. popen uses a completely different implementation
Don't know why, don't know whether it's behaving the same -->
</row>
<row>
<entry><function>mkdir</function></entry>
<entry>&sm.uidcheck.dir;</entry>
</row>
<row>
<entry><function>rmdir</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>rename</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir;<!-- on the old name only, it seems. Is rename preventing moving files? --></entry>
</row>
<row>
<entry><function>unlink</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir;</entry>
</row>
<row>
<entry><function>copy</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir; (pro
<parameter>source</parameter> a
<parameter>target</parameter>) </entry>
</row>
<row>
<entry><function>chgrp</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>chown</function></entry>
<entry>&sm.uidcheck;</entry>
</row>
<row>
<entry><function>chmod</function></entry>
<entry>&sm.uidcheck; Navc nemete nastavovat
SUID, SGID a sticky bit</entry>
</row>
<row>
<entry><function>touch</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir;</entry>
</row>
<row>
<entry><function>symlink</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir; (pozn.: testovn je pouze
cl)</entry>
</row>
<row>
<entry><function>link</function></entry>
<entry>&sm.uidcheck; &sm.uidcheck.dir; (pozn.: testovn je pouze
cl)</entry>
</row>
<row>
<entry><function>getallheaders</function></entry>
<entry>V bezpenm reimu nebudou hlaviky zanajc 'authorization'
(bez ohledu na velikost psmen) vraceny. Varovn: toto nefunguje
s aol-server implementac <function>getallheaders</function>!</entry>
</row>
<row>
<entry>Jakkoli funkce kter pouvaj
<filename>php4/main/fopen_wrappers.c</filename>
</entry>
<entry>??</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
</sect1>
</chapter>
<!-- 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:"../manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
-->
|
