Differences

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--- config:safemodehack [2011-06-09 09:08] – [Security Warning] 90.132.213.19
+++ config:safemodehack [2023-10-16 22:49] (current) – removed since release 2020 Hogfather Klap-in
@@ Line 1: / Line 1: @@
+====== Configuration Setting: safemodehack ======
+:!: Removed since release 2020 Hogfather)
+This tries to solve bug [[bug>179]] where DokuWiki can not write to
+directories it created itself. It does so by using FTP to log into your
+server and creating the directory that way. It requires the FTP PHP
+module to be installed on the server.
+---------
+  * Type: Boolean
+  * Default: 0
+As the name suggests, this is a hack and not recommended. Safemode
+itself is a setting that even the developers of PHP despise, it will be
+removed from future PHP versions all together.
+If you can, disable PHP's safemode instead of using this hack. Many
+providers will disable it for your site if you ask them nicely.
+===== When to use this hack =====
+On some hosts with restrictive settings there are limitations on PHP's
+filesystem functions, e.g. mkdir() etc. To be more specific, the
+settings are:
+  - safe_mode = On
+  - safe_mode_gid = Off
+A first indication for the need of the SafeMode Hack is the encounter of
+ error messages like this:
+  Writing ....../data/cache/9/9243162ecf6295fc6a1c487ca46c20fe.i failed
+The directory ''..../data/cache/9/'' will exist((check this, if doesn't
+exist you probably have a different problem)) but it will not be
+writable by DokuWiki. This is a typical symptom of the safe mode
+restriction. DokuWiki can't write to directories created by itself.
+===== Usage =====
+To enable it, set ''safemodehack'' to ''1'' and enter your FTP
+credentials into the config file. (i.e. ''conf/local.php'' Or just go to
+ the [[plugin:config|Configuration Manager]], which offers a great GUI
+for changing settings of DokuWiki.)
+If you have already tried running DokuWiki without the
+[[safemodehack|Safemodehack Option]], you have to **remove the
+subdirectories of /data/cache** to have them recreated with the correct
+UID in order for everything to work.
+Example Config:
+<code php>
+$conf['safemodehack'] = 1;
+$conf['ftp']['host'] = 'localhost';
+$conf['ftp']['port'] = '21';
+$conf['ftp']['user'] = 'user';
+$conf['ftp']['pass'] = 'password';  // plain text (see below)
+$conf['ftp']['root'] = '/home/user';
+</code>
+You may need to relax the directory permissions as well to make sure the
+ webserver is allowed to write to the new directories. The safemodehack
+alone may not solve the problem, since your FTP user has probably a
+different UID than the webserver. Change the [[config:dmode]] option
+from 0755 to 0777 may be required.
+==== Security Warning ====
+Using this method requires your ftp password to be stored in plain text
+in one of DokuWiki's configuration files.  These files may be world
+readable.
+Since Release Candidate 2009-01-26 the password may be
+//obscured//((this is not meant to be security, simply to prevent casual
+ revelation)) by being uuencoded. Setting the password using the
+admin/config settings page will do this automatically.
+==== Which value to use for the root option ====
+When DokuWiki tries to create a directory it strips the root part from
+the path before creating it over FTP. To do so it needs some info about
+the environment it will find at your FTP-server.
+Imagine you installed DokuWiki in ''/home/user/htdocs/dokuwiki'' with
+''/home/user/htdocs/dokuwiki/data'' as datadir. When you log in with FTP
+ you are [[man>chroot|chrooted]] to '/home/user', which means
+creating a directory ''/foo'' through FTP will really result in a
+directory ''/home/user/foo'' on the server. To tell DokuWiki about this
+you need to set ''$conf['ftp']['root']'' to ''/home/user/''.
+So if DokuWiki tries to create the directory
+''/home/user/htdocs/dokuwiki/data/mynamespace'' the safemode hack strips
+ the root part resulting in ''htdocs/dokuwiki/data/mynamespace'' this
+directory then will be created via FTP.
+If your FTP Server doesn't use any chroot (eg. you can [[man>cd]] up
+to ''/'' of the WebServer) you can leave the root option empty.
+To find the place where your are chrooted to on a webhost you first have
+ to find out the //absolute path// in which DokuWiki resides. This is
+usually something like
+''/srv/www/htdocs/your-ftp-username/html/dokuwiki'', but you can find it
+ out, by e.g. checking the PHP environment using this short script:
+<code php><?php phpinfo(); ?></code>
+This will print the webserver's PHP settings on the screen where you
+will find all the details. When you have the absolute path, log into
+your FTP account and compare what you see there with this path. Try
+moving to upper directories until it you reach the top. Now look which
+part of the absolute path you can see. If you are chrooted you probably
+can only see the ''html'' directory.
+So, if for example the username for your webspace is web123, and if you
+are chrooted to /srv/www/htdocs/web123, you have to set the root value
+to:
+<code>$conf['ftp']['root'] =
+'/srv/www/htdocs/web123';</code>
+===== Notes =====
+  * My ISP has both these safe_mode settings (see [[http://mcode1.free.fr|one of my sites]] for php_info), and I create pages with no need for the hack. It may depend on other variables too ([[mailto:dw-safe@mmichel.freesurf.fr|mathiasm]]).
+    * //Possible Answer:// The main difference between my non working settings and those of your ISP is that in your case PHP is run as CGI (Server API: CGI) where as in my case PHP is set up as Apache2 module (Server API: Apache 2.0 Handler). Might that be the cause that makes your installation work despite the safe_mode settings?
+  * **I did a "mkdir 1 2 3 4 5 6 7 8 9 0 a b c d e f" in data/cache and chmoded all these to 777. This seems to be a workaround, too.**
+    * This is not really a solution, because DokuWiki needs to create subdirectories for [[:namespaces]] as well, with the above method you'll still not be able to create new namespaces
+    * **If you don't need new namespaces, this is a workaround!**
+  * Even if you use the Safemode Hack, [[tips:disabled_functions|disabled php functions]] ((check the ''disable_functions'' value in [[phpfn>phpinfo]] output)) could break PHP output.
+  * The safemodehack may only work if you have the possibility of using the ftp service. I tried it with only webdavs available. Neither the ftp-hack nor a similar webdav configuration worked. So I'll have to try something else.
+===== See also =====
+  * [[:config:|Configuring DokuWiki]]