PHP change folder permissions for outgoing commands only - php

I have a file sharing website in the making where I am allowing the visual and function part of pages work. This runs into a problem when I want to allow server side scripting like php pages to be uploaded. This php (etc.) page could easily back link and delete files which I obviously would not want. I have changed the permissions many times to test but this also stops my php files from uploading and renaming files to these folders. I do want to allow these file types but im not sure what I can do.
I was thinking I could do this through .htaccess but I wouldn't know how.
Any suggestions?

I'm not sure, but it sounds like you want to allow arbitrary file uploads (including .PHP scripts) but to prevent any of them from being executed on the server side.
I would recommend creating a file storage directory that is not web-accessible (e.g. put it outside your www-root or use a .htaccess file to limit direct access). Then have your PHP scripts upload to that directory. Create a download script and have download access to those files go through that script, so that e.g. PHP files cannot be invoked remotely.

If I understand correctly from reading comments:
You want users to be able to upload any file. Including code. Including .php, .asp etc.
You want the users to be able to execute this code, but to limit the code to a "sandbox" environment.
Seems to me you should write your files to a specific location, which has its own document root/vhost (http://exec.domain.tld).
On that vhost you could set security, ie:
AllowOverride None # disable rewriting and such
php value disable_functions dl,exec,passthru,system,shell_exec,popen # disable functions
And to top it off (!important) set basedir restrictions to the vhosts document root
<Directory /srv/www/exec.domain.tld/docroot>
php_admin_value open_basedir /srv/www/exec.domain.tld/docroot
</Directory>
I haven't actually set up this environment, but I feel this is your best starting point. And I do think it'll work, if you fix the typo's/parameter name errors i might have made :)

I think it's not about permission, but php execution.
You can turn off php engine on a directory using .htaccess file, like this:
<IfModule mod_php5.c>
php_flag engine off
</IfModule>

Related

How can I make .htaccess files in a subfolder not execute?

I am creating a cloud storage project, and I want users to be able to upload any file. In particular, I want people to be able to upload .htaccess files, but I don't want Apache using these files as this is a security concern. How can I prevent Apache from using the user uploaded file, while still using my own .htaccess file in a parent folder?
This question is helpful reading. Directives near the www-root are applied first, subfolders are used later and may overwrite previous settings.
There are some things you can do:
Don't use .htaccess files at all, not even in other directories. If you have a dedicated server, you can edit the server config file, which is much more efficient. It will allow you to set AllowOverride None, which will prevent Apache from using .htaccess files at all. Instead, you can accomplish the same by putting your rules in the server config file. You'll need to restart Apache every time you make a change, and making an error in the server config file will prevent Apache from starting until it is fixed.
Store your files as random characters without an extension, make it impossible to access any files directly, and instead rely on a database to map a filename to a file. This allows you to store files securely, while not dumping everything in your database.
You cannot put anything in your .htaccess file that would prevent .htaccess files in subdirectories to be ignored, because AllowOverride only works in directory context, not in .htaccess context.

securing outward-facing website db configs

I'm adding some database usage to a public facing site, and I wanted input on what the most secure way to store mysql connection information might be. I've come up with a few options:
First I could store the config in another directory, and just set the PHP include path to look for that dir.
Second, I know there are some files that apache won't serve to browsers, I could use one of these types of files.
Third, I could store encrypted files on the server, and decrypt them with PHP.
Any help would be much appreciated.
Storing the config outside of apache's document root is a must
You can configure apache to disallow any files with htaccess.
in the config folder add a .htaccess with the following
order allow,deny
deny from all
If you don't want to use .htaccess as #johua k, mentions, instead add
<Directory /home/www/public/config>
order allow,deny
deny from all
</Directory>
to your apache config.
This will deny any files in that folder from being served to anyone, which is fine since php doesn't care about htaccess you can just
include('config/db.php')
If you properly config your php scripts, they should never appear in plain text.
so a file like
define('mysql_password', 'pass')
would never display that text.
If you are worried about a shared hosting environment and another use having access to read this file then you should evaluate the security of the linux installation and the host. Other users should have any browsing access to your file. From the web files marked php should never return source.
You can explicitly tell apache not to serve the files ever, so they would only be include() or require() able.

Using .htaccess, prevent users from accessing resource directories, and yet allow the sourcecode access resources

Apologies if my question is unclear, but I'm not quite up with the jargon. By 'resource directories' I mean my css, php scripts, images, javascript ect.
I used an .htaccess file in my images directory that contained
deny from all
to do this. Though this prevented people from typing "www.example.com/images" into their browser and accessing my images directory, the images stopped appearing on my website.
I assume this is because the .htaccess file is even denying my source code from accessing the images. How can I let my source code access directories? I also have a cron job running a php script every night. The cron job also needs to be allowed to access the scripts directory.
Also, is using .htaccess files even the best way to secure a site?
To prevent someone to view your images directory, you need to disallow Directory Listing.
http://viralpatel.net/blogs/htaccess-directory-listing-enable-disable-allow-deny-prevent-htaccess-directory-listing/
You cannot use deny from all, because nothing can be loaded from that directory from a web browser, so your images which you load with on your website won't load either.
Options -Indexes will disallow people to list files in your images directory. Please see http://viralpatel.net/blogs/htaccess-directory-listing-enable-disable-allow-deny-prevent-htaccess-directory-listing/
For securing data from being viewed by people who shouldn't you can use a authentication. You can setup a login field with htaccess, or script one with, for example PHP or python.
Login script with htaccess:
Script:
http://www.htaccesstools.com/htpasswd-generator/
Password file:
http://www.htaccesstools.com/htaccess-authentication/
You can prevent from accessing any directory you want:
Add this snippet in your httpd.conf file (you can find httpd.conf file here C:\wamp\bin\apache\apache2.4.9\bin)
<Directory "c:/wamp/www/directory_A/">
Options -Indexes
</Directory>
In this case you can access www directory but can't inside directory_A.
or
<Directory "c:/wamp/www/directory_A/uploads/">
Options -Indexes
</Directory>
In this case you can access 'directory_A/' directory but can't inside 'uploads/'.

php.ini wont work outside public_html directory

Just very quick question about php.ini file. I created my own on my php.ini file and it works fine if I put it inside my 'public_html' directory. However the problem is it can obviously be viewed in browser through HTTP requests.
So, I am trying to move it outside my 'public_html' directory however it does not seem to work when outside my 'public_html'.
I know I could perhaps set in my .htaccess the following to avoid it being read:
<Files php.ini>
Order allow,deny
Deny from all
</Files>
However I do not want to do this as my php.ini can still get cached by Google if it's in the 'public_html' directory. Is there any suggestions to make it work outside my public_html?
I am running an Apache server. Thanks for any suggestions
You can use the PHPRC environment variable...see the documentation:
http://www.php.net/manual/en/configuration.file.php
It can't get cached by google if you block like that in .htaccess
Two suggestions:
Ensure that Apache can find your php.ini (PHPINIDIR /path/where/php.ini/is/located)
Ensure the file is readable by the webserver user.
How is it that you php.ini came to be in a web server accessible folder? It is the first time I hear of such a situation.
I thought hard on how you managed to do this, and the only answer I came up with is that you created a vhost in php folder. If that is the case, create another vhost out of the php.ini path, and remove the offending vhost. See this post for examples.

Custom Log File with Correct Permissions

I have a processing file for my website's payments. It works just fine, but what I would like to do is log all the requests to this page so that if anything throws an error, the raw data is saved and I can process the transaction manually. The processing file uses fopen to write to the log file in another directory.
What I have right now is a separate folder on my root directory with permissions 755. Then a log file inside with permissions 777. The processing file that writes to the log file, in PHP if that matters, is set to 777.
This works right now, but the log file is publicly available. I know I can be doing this better and that the permissions aren't correct. How can I do this better?
Put the log file outside the document root. The PHP script that writes to it will still be able to get to it (via the full path) but Apache won't be able to serve it.
I came across this whilst searching the answer for myself. I don't believe there is a simple "permissions fix" to do what you want and perhaps the safest way is to put the log files outside of public_html directory.
However this can be a nuisance sometimes - especially if you are wanting to e.g. catch paypal ipn dump text in a log file, but not have it publicly accessible.
In such cases, you can use .htaccess file directives to allow write from script, but deny reading from public access.
For example, this works for me (Apache .htaccess in root public_html folder);
<FilesMatch "mycustom\.log">
Order allow,deny
Deny from all
</FilesMatch>
and if you have multiple logs you want to protect, use it like this, with "Pipe Separated";
<FilesMatch "mycustom\.log|ipn_errors\.log">
Order allow,deny
Deny from all
</FilesMatch>
It is worth noting that the above directives are deprecated as of apache 2.4 and you may wish to consider using more current directives instead: https://httpd.apache.org/docs/2.4/howto/access.html
Hope that helps you!

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