How should I choose an authentication library for CodeIgniter? [closed]

Update (May 14, 2010):

It turns out, the russian developer Ilya Konyukhov picked up the gauntlet after reading this and created a new auth library for CI based on DX Auth, following the recommendations and requirements below.

And the resulting Tank Auth is looking like the answer to the OP's question. I'm going to go out on a limb here and call Tank Auth the best authentication library for CodeIgniter available today. It's a rock-solid library that has all the features you need and none of the bloat you don't:

Tank Auth

Pros

Full featured

Lean footprint (20 files) considering the feature set

Very good documentation

Simple and elegant database design (just 4 DB tables)

Most features are optional and easily configured

Language file support

reCAPTCHA supported

Hooks into CI's validation system

Activation emails

Login with email, username or both (configurable)

Unactivated accounts auto-expire

Simple yet effective error handling

Uses phpass for hashing (and also hashes autologin codes in the DB)

Does not use security questions

Separation of user and profile data is very nice

Very reasonable security model around failed login attempts (good protection against bots and DoS attacks)

(Minor) Cons

Lost password codes are not hashed in DB

Includes a native (poor) CAPTCHA, which is nice for those who don't want to depend on the (Google-owned) reCAPTCHA service, but it really isn't secure enough

Very sparse online documentation (minor issue here, since the code is nicely documented and intuitive)

Download Tank Auth here

Original answer:

I've implemented my own as well (currently about 80% done after a few weeks of work). I tried all of the others first; FreakAuth Light, DX Auth, Redux, SimpleLogin, SimpleLoginSecure, pc_user, Fresh Powered, and a few more. None of them were up to par, IMO, either they were lacking basic features, inherently INsecure, or too bloated for my taste.

Actually, I did a detailed roundup of all the authentication libraries for CodeIgniter when I was testing them out (just after New Year's). FWIW, I'll share it with you:

DX Auth

Pros

Very full featured

Medium footprint (25+ files), but manages to feel quite slim

Excellent documentation, although some is in slightly broken English

Language file support

reCAPTCHA supported

Hooks into CI's validation system

Activation emails

Unactivated accounts auto-expire

Suggests grc.com for salts (not bad for a PRNG)

Banning with stored 'reason' strings

Simple yet effective error handling

Cons

Only lets users 'reset' a lost password (rather than letting them pick a new one upon reactivation)

Homebrew pseudo-event model - good intention, but misses the mark

Two password fields in the user table, bad style

Uses two separate user tables (one for 'temp' users - ambiguous and redundant)

Uses potentially unsafe md5 hashing

Failed login attempts only stored by IP, not by username - unsafe!

Autologin key not hashed in the database - practically as unsafe as storing passwords in cleartext!

Role system is a complete mess: is_admin function with hard-coded role names, is_role a complete mess, check_uri_permissions is a mess, the whole permissions table is a bad idea (a URI can change and render pages unprotected; permissions should always be stored exactly where the sensitive logic is). Dealbreaker!

Includes a native (poor) CAPTCHA

reCAPTCHA function interface is messy

FreakAuth Light

Pros

Very full featured

Mostly quite well documented code

Separation of user and profile data is a nice touch

Hooks into CI's validation system

Activation emails

Language file support

Actively developed

Cons

Feels a bit bloated (50+ files)

And yet it lacks automatic cookie login (!)

Doesn't support logins with both username and email

Seems to have issues with UTF-8 characters

Requires a lot of autoloading (impeding performance)

Badly micromanaged config file

Terrible View-Controller separation, with lots of program logic in views and output hard-coded into controllers. Dealbreaker!

Poor HTML code in the included views

Includes substandard CAPTCHA

Commented debug echoes everywhere

Forces a specific folder structure

Forces a specific Ajax library (can be switched, but shouldn't be there in the first place)

No max limit on login attempts - VERY unsafe! Dealbreaker!

Hijacks form validation

Uses potentially unsafe md5 hashing

pc_user

Pros

Good feature set for its tiny footprint

Lightweight, no bloat (3 files)

Elegant automatic cookie login

Comes with optional test implementation (nice touch)

Cons

Uses the old CI database syntax (less safe)

Doesn't hook into CI's validation system

Kinda unintuitive status (role) system (indexes upside down - impractical)

Uses potentially unsafe sha1 hashing

Fresh Powered

Pros

Small footprint (6 files)

Cons

Lacks a lot of essential features. Dealbreaker!

Everything is hard-coded. Dealbreaker!

Redux / Ion Auth

According to the CodeIgniter wiki, Redux has been discontinued, but the Ion Auth fork is going strong: https://github.com/benedmunds/CodeIgniter-Ion-Auth

Ion Auth is a well featured library without it being overly heavy or under advanced. In most cases its feature set will more than cater for a project's requirements.

Pros

Lightweight and simple to integrate with CodeIgniter

Supports sending emails directly from the library

Well documented online and good active dev/user community

Simple to implement into a project

Cons

More complex DB schema than some others

Documentation lacks detail in some areas

SimpleLoginSecure

Pros

Tiny footprint (4 files)

Minimalistic, absolutely no bloat

Uses phpass for hashing (excellent)

Cons

Only login, logout, create and delete

Lacks a lot of essential features. Dealbreaker!

More of a starting point than a library

Don't get me wrong: I don't mean to disrespect any of the above libraries; I am very impressed with what their developers have accomplished and how far each of them have come, and I'm not above reusing some of their code to build my own. What I'm saying is, sometimes in these projects, the focus shifts from the essential 'need-to-haves' (such as hard security practices) over to softer 'nice-to-haves', and that's what I hope to remedy.

Therefore: back to basics.

Authentication for CodeIgniter done right

Here's my MINIMAL required list of features from an authentication library. It also happens to be a subset of my own library's feature list ;)

Tiny footprint with optional test implementation

Full documentation

No autoloading required. Just-in-time loading of libraries for performance

Language file support; no hard-coded strings

reCAPTCHA supported but optional

Recommended TRUE random salt generation (e.g. using random.org or random.irb.hr)

Optional add-ons to support 3rd party login (OpenID, Facebook Connect, Google Account, etc.)

Login using either username or email

Separation of user and profile data

Emails for activation and lost passwords

Automatic cookie login feature

Configurable phpass for hashing (properly salted of course!)

Hashing of passwords

Hashing of autologin codes

Hashing of lost password codes

Hooks into CI's validation system

NO security questions!

Enforced strong password policy server-side, with optional client-side (Javascript) validator

Enforced maximum number of failed login attempts with BEST PRACTICES countermeasures against both dictionary and DoS attacks!

All database access done through prepared (bound) statements!

Note: those last few points are not super-high-security overkill that you don't need for your web application. If an authentication library doesn't meet these security standards 100%, DO NOT USE IT!

Recent high-profile examples of irresponsible coders who left them out of their software: #17 is how Sarah Palin's AOL email was hacked during the Presidential campaign; a nasty combination of #18 and #19 were the culprit recently when the Twitter accounts of Britney Spears, Barack Obama, Fox News and others were hacked; and #20 alone is how Chinese hackers managed to steal 9 million items of personal information from more than 70.000 Korean web sites in one automated hack in 2008.

These attacks are not brain surgery. If you leave your back doors wide open, you shouldn't delude yourself into a false sense of security by bolting the front. Moreover, if you're serious enough about coding to choose a best-practices framework like CodeIgniter, you owe it to yourself to at least get the most basic security measures done right.

<rant>

Basically, here's how it is: I don't care if an auth library offers a bunch of features, advanced role management, PHP4 compatibility, pretty CAPTCHA fonts, country tables, complete admin panels, bells and whistles -- if the library actually makes my site less secure by not following best practices. It's an authentication package; it needs to do ONE thing right: Authentication. If it fails to do that, it's actually doing more harm than good.

</rant>

/Jens Roland

Note that the "comprehensive listing" by Jens Roland doesn't include user roles. If you're interested in assigning different user roles (like admin/user or admin/editor/user), these libraries allow it:

Ion_Auth (rewrite of Redux)
Redux
Backend Pro

Tank_Auth (#1 above in Jens's list) doesn't have user roles. I realize it's not exactly part of authentication, but since

authentication and role management are both handled upon page load
Both involve security
The same table/model can be used for both.
Both can be set up to load in the controller constructor (or even autoload)

It makes a LOT of sense to have one library to handle both, if you need it. I'm switching to Ion_Auth from Tank_Auth because of this.

Ion_auth! Looks very promising and small footprint! I like..

http://github.com/benedmunds/CodeIgniter-Ion-Auth

I'm the developer of Redux Auth and some of the issues you mentioned have been fixed in the version 2 beta. You can download this off the offcial website with a sample application too.

Requires autoloading (impeding performance)

Uses the inherently unsafe concept of 'security questions'. Dealbreaker!

Security questions are now not used and a simpler forgotten password system has been put in place.

Return types are a bit of a hodgepodge of true, false, error and success codes

This was fixed in version 2 and returns boolean values. I hated the hodgepodge as much as you.

Doesn't hook into CI's validation system

The sample application uses the CI's validation system.

Doesn't allow a user to resend a 'lost password' code

Work in progress

I also implemented some other features such as email views, this gives you the choice of being able to use the CodeIgniter helpers in your emails.

It's still a work in progress so if have any more suggestions please keep them coming.

-Popcorn

Ps : Thanks for recommending Redux.