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Date: Wed, 13 Jun 2012 23:31:35 +0200
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Subject: Adding a simple API for secure password hashing?
From: nikita.ppv@googlemail.com (Nikita Popov)

Hi internals!

Recent incidents have shown that even very large websites still don't
get how to do password hashing properly. The sha1 hashes used by
Linkedin et al can be easily cracked even by amateurs without special
hardware.

What could be the reason for this? Why don't people use bcrypt? It is
being recommended already for *years*, but still most people don't
seem to make use of it.

I think the reason is that it is incredibly hard to use crypt()
correctly, mainly for the following reasons:

* For many people the syntax is hard to grasp. The hashing algorithm
is specified as the salt parameter, which is somewhat non-obvious (at
least for me).
* The fact that you verify a password using $hash == crypt($password,
$hash) is equally non-obvious.
* Generating correct salts for bcrypt is quite complicated. It is
encoded in some strange base64 format, thus requiring an additional
function to create it. Additionally it isn't particularly easy to
fetch the random bytes for the salt as you have to check several
possibilities for a cross-platform solution (mcrypt initialization
vector, openssl, /dev/*random, mt_rand etc).

Correctly hashing a password with bcrypt thus requires about a hundred
lines of code. So one either has to import a library (and strangely it
seems that people don't like to do that!) or has to roll your own
(usually implementing some part incorrectly...)

Obviously it's somewhat tempting to use a one-liner sha1() hash
instead of a hundred line bcrypt hash.

So, wouldn't it be better if PHP provided an easy to use API for
secure password hashes natively? So you just have to call a single
function, which magically handles everything for you (like salt
generation).

A simple sample API could be two functions password_hash($password)
and password_hash_verify($password, $hash). But it could just as well
be a fancy, extensible OOP API.

I think this would greatly improve the hashing situation for PHP.

Thanks,
Nikita