As per question, is it safe to store passwords on php pages such as
$password = 'pa$$w0rd';
If the users can't see it, it's safe, right?
EDIT: Some people actually suggested using hash, however, there would be a problem with database server connection password, wouldn't it?
Unless the site itself is compromised and now so are all the things those passwords grant access to (your DB, perhaps?).
It depends how you define 'safe'.
You are right in that a general user won't see it.
However it is definitely a bad practice; if your site is compromised, what else will these passwords give access to? I'd say at a bare minimum you should be storing a hash of the password, not the plaintext.
Usually they can't see it. But if something bad happens on server there's a big possibility that server will return your php code in plain text w/o executing it and therefore user will see all source of that file and also your password.
I would store password somewhere where it's not on document root (Cannot be open in browser) and then open that file with php and read the content (password). Or if you have multiple passwords/users, I'd store them in database for fast access.
If you want to use the file method directory layout should look something like this (depneds on server)
/public_html/index.php
/password.txt
$myFile = $_SERVER['DOCUMENT_ROOT'] + "/../password.txt";
if file_exists($myFile) {
$fh = fopen($myFile, 'r');
$password = fgets($fh);
fclose($fh);
} else die("No password file");
if ($user_input == $password) {
...... Authentication succeeded ..........
......your relatively protected code .....
} else die("Wrong password");
If you want even more security instead of storing password as text in that text file. Sore it's hash and then when you want to compare it with user input generate hash from the user input and compare it to the password's hash you loaded from text file
sha1($user_input) == $password_from_txt
As long as your PHP installation works as it should, this is no less secure than any other method. I would prefer named constant (define) over variable. Additionally you might consider storing a hash of the password, instead of plain password. This prevents stealing your passwords even if the site is compromised.
As for being bad practice, it depends. If you need to store just one password, this approach is ok. Storing them outside document root may give a false feeling of extra security; the document root is no more absolute than any other setting of the server.
The short answer is both No, and It Depends.
It's almost never a good idea to store passwords in plain text, especially in a web accessible location, if for no other reason than a simple server misconfiguration or an echo in the wrong place could expose it to the world.
If you MUST store a password, (which is possible) you could try to store it outside the webroot, eg
/var/www/public_html/ Put your codez here
/var/www/includes/ Put your passwords here
Even better than that would be to have the system that you need the password for (eg a database wrapper ) return an object already instantiated. so rather than asking for $databasepassword you ask for a PDO object, and store your database classes outside the webroot.
The It Depends comes from what attack vectors would cause someone to have access to that password text, and would it require them to be already inside your filesystem, if so, you're probably screwed anyway.
Also, if its the password to your supa-secrit subscriber content, meh, all you've lost is some subscription fees, if its your database, you may have a problem, if it's your online banking details, um good for you.
How valuable is the thing the password is protecting?
Depending on how you define safe, any approach has its positive and negative aspects.
If you really want to store a password in your source, it might be a good idea to do something of the sort:
File: config.php
if( ! defined('IN_CODE') ) die( 'Hacking attempt' );
define( 'PASSWORD_HASH', '098f6bcd4621d373cade4e832627b4f6' );
File: index.php
define( 'IN_CODE', '1' );
include( 'passwd.php' );
if( md5($password) == PASSWORD_HASH )
...
Plain-text is never a good idea, always store a hash of the password you want to store.
Furthermore, try to seperate defines like this from your main sourcefile.
Sometimes it just has to be f.e. for a mail application where you can only login with the plain password and not with a hash. And if your application doesn't have security issues it should not affect you.
I belive that most of the times plain text password would be database password as MySQL, for exmaple, won't accept hash for authentication.
As mentioned before best solution is to keep PHP config file with password outside the webroot.
If you are worried that someone may see your password while you viewing the file you can simply make it unreadable for human using base64 funciton.
See this post for details and even small utility for Windows, Linux and Mac that makes it easier.