Is it considered good or bad practice to use MySQL's password function to hash passwords used by an application? I can see pros and cons. I'm curious if there is a general consensus on whether it is good or bad.
+5
A:
If you are using a database function to hash passwords then by definition they have to arrive in the database unhashed: I would therefore prefer to do it much nearer the "source" i.e. in the frontend application so you're not passing around exposed information.
davek
2009-11-17 19:25:29
+1 salting and hashing account passwords is an application issue, not something you'd want to rely on the DBMS's particular implementation for.
bobince
2009-11-17 19:30:59
Word, this is not something you want to use. Just look at OLD_PASSWORD and the PITA that occurred when MySQL changed their hashing method. Much better to do it in the app, imo.
cookiecaper
2009-11-17 20:16:47
+2
A:
I believe the actual PASSWORD function in MySQL is insecure, and has been broken, but I can't find a link at the moment. I know the older one (OLD_PASSWORD in 5 and up) is definitely insecure.
Of course, all passwords should always be stored with a salt (for further obscurity). Example:
UPDATE users SET password=MD5(CONCAT('salt', 'user provided value')) WHERE id=54
There is also the MD5 function, but with the rise of colossal rainbow tables, it's not 100% reliable as a way of completely obfuscating stored passwords.
A better method is hashing the password (with a salt) before it reaches the database. Example:
<?php
$password = sha1(SALT.$_POST["password"]);
$sql = "UPDATE users SET password='".$password."' WHERE id=54";
?>
davethegr8
2009-11-17 19:33:26
Looking at the code of password.c, MySQL 4.1+ password are encoded simply with SHA1 applied twice to the input (with no salt) and converted to a hex string.
Bill Karwin
2009-11-17 19:56:39
+5
A:
The docs for MySQL's PASSWORD() function states:
The PASSWORD() function is used by the authentication system in MySQL Server; you should not use it in your own applications.
Read "You're Probably Storing Passwords Incorrectly" for better advice on hashing and storing passwords.
MD5 and SHA-1 are considered to be too weak to use for passwords. The current recommendation is to use SHA-256.
I contributed a patch to MySQL to support a SHA2() function, and the patch was accepted, but since their roadmap has changed it's not clear when it will make it into a released product.
In the meantime, you can use hashing and salting in your programming language, and simply store the result hash digest in the database. If you use PHP, SHA-256 is available in the hash() function.
Bill Karwin
2009-11-17 19:42:40