I know ASP.NET supports various authentication models like, Windows, Forms, passports and recently Claims.
I have an asp.net that prompts user to enter user name/password to login, it then compares the input username/password with the entries inside the user table of the application's Database. So, my question is, what is the term/name for this kind of authentication model? Where does this fall in the above mentioned ASP.NET supported authentication model?
I also see that many of the internet sites that I know uses this same approach.
(note: I'ev kept my App simple, of course it has user registeration/add page, profile table to authorize users, etc)
Windows, Forms, Passport, Claims, etc.. authentication are BROWSER authentication schemes. They are the mechanism the browser communicates with the server to present credentials. They have nothing to do with databases or any other storage mechanism (well, mostly..). Those are just implementation details.
FormsAuthentication uses a cookie to store an encrypted value that tells the server that the user has been authenticated. How the user is authenticated, be it by comparing things to databases, using a service, etc.. is all irrelevant if the end result is that a FormsAuthentication cookie is issued.
WindowsAuthentication is a little different in that the browser and the web server communicate to share a Kerberos ticket to verify identity, or the user enters the username password into a box that the server requests the browser to pop up. In this mode, the server itself manages the way that authentication occurs and the app isn't involved.
BasicAuthentication uses an HTTP Header to send the password in cleartext, well, technically it's an encoded password, but it's well known so anyone can unencode it. Again, the actual method that it stores the data is up to the server, and the server does this without an applications knowledge. The important part is that it's accomplished via an HTTP Header.
The same is true of other types of authentication, which are all just variations on the cookie and/or header mechanisms.
The point here is that Authentication is about how any given HTTP request identifies who the user is to the server, and ultimately the application. Not how the data is stored, or validated. So, since you did not tell us how the server and browser communicate, we can't tell you how your authentication is defined, although almost certainly it is a variation of FormsAuthentication.
EDIT:
Just a little history lesson. The reason it's called FormsAuthentication is because the authentication system does not use a pop up dialog box from the browser to enter credentials, but typically the web page provides an HTML Form for the user to enter credentials. The browser is not really involved in the authentication process at all, other than for passing a cookie as requested.
It should be more accurately called "CookieBasedAuthentication", but the name has stuck and will probably stay what it is. ASP.NET provides a specific implementation called FormsAuthentication, but you can do the same thing with any cookie based authentication scheme (although I do not recommend rolling your own, you will almost certainly make security mistakes).
Some people think that storing a flag in Session is good enough. Do not, under any circumstances, ever use Session to store authentication information. Session cookies are not encrypted and are easily stolen and/or spoofed. Use a well known method.
The other answers might have already showed most of the details. But if we categorize carefully on IIS and ASP.NET levels, below are the differences you should pay attention to,
IIS Authentication
This occurs first, as HTTP packets arrive at IIS level first. IIS supports several ways,
Anonymous (the anonymous user account configured in IIS configuration)
Windows (browser side user)
Basic (browser side user)
Digest (browser side user)
How those authentication methods work at packet level requires you to capture network packets and dive into the conversation at that level.
The result of this authentication is that IIS generates a user token and passes on to ASP.NET pipeline.
ASP.NET Authentication
ASP.NET has several authentication methods of its own,
Windows (here ASP.NET trusts and interprets the user token IIS passes, and determines which ASP.NET user identity should be created and which roles it supports, without doing further authentication on ASP.NET level.)
Forms (based) authentication (where ASP.NET ignores the user token, and uses cookies or similar mechanism to build a high level authentication approach. On IIS side you usually set anonymous authentication.)
Claims based authentication, OpenID, OAthen and so on are similar to Forms based, where they don't care much about the user token generated by IIS.
It is possible to use non-anonymous on IIS plus non-Windows on ASP.NET side to set up the so called mixed authentication.
All the Authentication methods that require the user to input a Username and Password that you maintain are a form of Forms Authentication. This is because you are asking them to fill out a form (Username and Password) in order to authenticate them.
Read more about it Here or Here.
Edit: The answer provided by Mystere Man is much more complete and accurate than mine.
Related
We are running a Saas ASP.NET 3.5 Web application using Forms authentication on a IIS 7.5 public server with protected content for thousands of users. We also have some subapplications running ASP.NET MVC 2.
Usernames and passwords are stored in our database and every user has roles and groups attached, with privileges and access rights defined.
Now we have been asked to also facilitate for simple SSO login via Active Directory so that users do not have to enter username and passwords twice to login. These users will originate from different networks and domains.
No user "sync" should take place from our servers to LDAP serves. We are not sure that any communication with LDAP is needed since all users will be created in our system and maintained there. Forms authentication will be used for most of our users.
From here on we are unsure which is the best path to choose. For our scenario what would be the "best practice" way to proceed?
The simple answer is SAML. It is considered the "best practice" and many large SAAS providers support it.
SAML protocol defines the single sign on flow between multiple systems. It establishes trust between systems using certificates. Your application accepts an assertion containing attributes (user id, name, email address, etc.) from other systems. Your app will map the user into your user store.
In .NET world there are several options. You can find a library that implements SAML (ComponentSpace has one) and hook it into ASP.NET authentication. You can create your own using Windows Identify Framework (WIF). Here's the boatload of WIF videos http://www.cloudidentity.com/blog/2010/06/23/ALL-WILL-BE-REVEALED-7-HOURS-RECORDINGS-FROM-THE-WIF-WORKSHOPS/. You can try IdentityServer http://thinktecture.github.io/
Depending on how secure your app must be, you can opt for a simple option of passing user id from trusted networks using a simplified method. I've seen apps that allow user id to be sent via URL parameter or form field. Of course, this is horribly insecure, and you are taking on more risk, because the trust between two networks is not cryptographically enforced. You can mitigate it somewhat by checking referrer string or IP address (if you can isolate IP range of a corporate network for example). But you are still open to spoofing because any user can impersonate others by simply replacing user id within HTTP request.
It probably doesn't answer your question fully, but hopefully points you in the right direction.
I recommend looking into ADFS 2.0 it is very powerful in terms of claims mapping and works with AD: http://msdn.microsoft.com/en-us/magazine/ee335705.aspx
What you would make is a token consuming portion of your app that would receive and parse the final claims returned to your web server after the authentication loop.
I want to create a authorization mechanism for an application based on WebAPI and AngularJs.
I've seen some articles, which use BasicHttpAuthentication, but i really don't like the whole idea of sending username, and password on every request. The more it doesn't fit for me is because i want to use OpenId authentication, where you don't have username/password pair.
I'm thinking about a solution, but I don't really know how to implement it. The concept is that user is authenticated as in an usual Web application - posts a form with user / password or selects an OpenId provider. If the user is authenticated succesfully, it is placed in a static object, which stores the User object for a certain ammount of time. Next a usertoken is generated and passed to the Client Application. The client passes the token on each request to the server, if the user exists in the above mentioned static object with the appropriate authentication token it is authorized to get the data.
Firstly - Do you think this is a good approach to the problem?
Secondly - How should I pass the authentication token, WITHOUT using cookies? I guess it should sit in the request headers, like in BasicHttpAuthentication but, I really dont' know how to handle it.
BasicHttpAuthentication
I'm with you on feeling dirty about caching the username and password on the client and forever transferring it with every request. Another aspect of Basic authentication that might work against you is the lack of sign-off. Other than changing the password, you can't "invalidate" a basic authentication session. Tokens on the other hand, will typically offer an expiration date, and if you want server-side invalidation you can check the issue date and say "any tokens older than issue date xyz are invalid".
Server State
You mention "If the user is authenticated successfully, it is placed in a static object". But this is independent of the token? This sounds like you're wanting to implement server state management of authentication sessions, but this isn't strictly necessary. The token itself should be sufficient for user authentication, managing server state is another potential obstacle. Server state can become difficult to manage when you factor app-pool recycles or web-farm environments (what if you want two services to share the same authentication token, but not require communication with a central "authentication server" for storing the state / session?)
Passing Authentication Token
Headers is definitely a good place for it. Really, where else is there? Cookies, Headers, Message. Other than a browser client, cookies don't make a lot of sense, and including it in the message can muddy your message formatting a bit, so headers is the only remaining option that makes much sense in my view.
Client Implementation
You've not specified, but I suspect you're interested in calling the service from .NET? In which case System.Net.Http.HttpClient could be your friend. In particular, the DefaultRequestHeaders collection. You can use this to add a custom header to store your authentication token.
Server Implementation
When researching ASP.NET authentication recently, I learned a lot about customisation by examining the Mixed Authentication Disposition ASP.NET Module (MADAM). I wasn't interested in using MADAM as-is, but learning about it from that article and examining the source code gave me a lot of ideas of how I could insert my own authentication module into the web stack.
I'm writing an internal web application right now (with ASP.Net Web Forms), and it presents an odd problem. I have to be able to impersonate the currently logged in windows user, and execute a command based on their Windows Authentication to log in.. AND ... if they don't have Windows Authentication set up in the application I have to use to log them in, I have to be able to accept a user name and password. I also have to write the application in .Net 4.0, and secure it as much as possible. I got this to work by NOT utilizing Windows Authentication or Forms Authentication in the web.config, and instead setting session variables to guard against user accessing pages in the web app other that the log in. I did this by creating an oddly name session variable with a value based on their user name (windows auth or not), and then a secret session variable. The secret variable is in the web.config as a 256bit encrypted string, in which I decrypt, and set as the session secret. In order for the page to load, the first session variable can't be blank, and the second variable has to equal the decrypted key value... if the variables don't pass inspection, it redirects them to the login page. I set this up on every page, generic handler, and webservice method in the web app. I make the session timeout after a few minutes of no activity, and on log out, I set all session variables to nothing, and expire all cookies. (I also disable all cache).
My question is... Does this offer comparable security to that of Forms authentication? I have always used Forms authentication, but can't use it here. If I did, the users would have to reconfigure settings in IIS and in he web.config to toggle login procedures (From my knowledge, you can't use both Forms authentication, and windows authentication to manage the security of your pages and other web resources). With the method described above, I can accomplish the best of both worlds, but am curious about the security of my methods. Is there anything else I can implement here to assure the utmost security other that using forms authentication? Is it possible to accomplish the same level of security of Forms authentication without using it?
Thank you for any insight in advance!
Does this offer comparable security to that of Forms authentication?
No
The first rule when it comes to security is don't reinvent the wheel unless you absolutely have to. Any home baked solution you come up with has the potential to be as secure as a provided one like Windows or Forms Authentication. The problem is that home-grown solutions rarely reach that potential. They may test okay, but subtle bugs can remain. You don't want to find out a year later that you were hacked six months ago. Existing solutions have already been tested and used in millions of applications, whereas yours will be used in one application and tested by a handful of people at most.
A quick search suggests that it is possible to implement both Windows and Forms Authentication in the same application, so I'd pursue it further.
Mixing Forms and Windows Security in ASP.NET
I have the usual requirement of implementing Authentication and Authorization. I used to implement it using custom code where I have Users, Roles, Role_Pages, User_Pages, and User_Roles. So this way we can give a certain user roles (that group multiple pages) and/or directly define access to certain pages. All that with the ability to specify fine grained permissions like the ability to Add/Edit/Delete records in those pages.
My question: How easy is it to implement this using Forms Authentication and what advantage does that give over implementing a custom solution. I am also concerned with knowing if there would be any advantage when it comes to securing from session hijacking and against spoofing where an attacker could replay requests and impersonate legit users. Would Forms Authentication have any advantage there, or is it only SSL that can secure against that (which makes both approaches equal in that regard).
Forms authentication is just a mechanism for passing an authentication token from the browser to the server, which serves as the requestor's identity. I take it right now you're using a Session variable to remember the logged in user's information? That is akin to forms authentication because Session state is maintained (in part) through a cookie. Similarly, forms authentication creates a tamper-proof identity token and stores it using a cookie so that when the user makes subsequent requests, the cookie is sent to the server, which says, "Hey, I'm user X." Forms authentication, as it's name says, is just a mechanism for authenticating - that is, identifying - visitors.
For authorization you would typically use URL authorization, which is a mechanism through which you specify in Web.config, These are pages that are (or are not) accessible to certain users (and/or roles). Again, though, URL authorization, as its name implies, is just a mechanism for authorizing users, for determining if a given requestor has the rights to retrieve a certain resource.
So how do you store user information, like username, email, password, and so forth? That's where Membership comes into play. It's an extensible framework for creating and storing and managing user accounts. There's also the Roles system, which is a similarly extensible model for creating roles and associating them with users.
These, then, are the tools and frameworks you should explore: forms authentication, URL authorization, Membership, and Roles. They are complementary technologies and are (usually) used in tandem.
To address you specific questions:
How easy is it to implement this using Forms Authentication and what advantage does that give over implementing a custom solution.
Forms authentication (and URL auth and Membership and Roles) are pretty easy to implement. There are three primary advantages to using these technologies rather than a custom solution:
Using these technologies is more efficient. You don't have to reinvent the wheel, thereby saving you oodles of time.
Using these technologies leads to less buggy code. If you implement a custom solution you may have a security hole or bug that you don't catch during testing. Forms auth and URL authorization have both been around since ASP.NET's inception (nearly a decade now) and have been used and "tested in the field" by millions of developers around the world. Membership and Roles have been around for 5-6 years with similar levels of field testing. Obviously, you can't say the same about your custom solution.
Using these technologies makes your application more maintainable. If you need to hire a new dev to help on the site, chances are she'll already be familiar with forms auth et al, but would need to spend time to come up to speed with your custom solution.
I am also concerned with knowing if there would be any advantage when it comes to securing from session hijacking and against spoofing where an attacker could replay requests and impersonate legit users. Would Forms Authentication have any advantage there, or is it only SSL that can secure against that (which makes both approaches equal in that regard).
Forms auth has very tight security (presuming you're using the default settings). The authentication ticket is encrypted and digitally signed and has a time-based expiry built in (to reduce the surface area for replay attacks). I'm not sure your what your current, custom solution uses for identity since you didn't mention it, but I'd wager it's session state. That will be just as "secure." The point is, the identity tokens - the session cookie in your case and the authentication ticket in the case of forms auth - are both secure and can be safely transmitted over the Internet without SSL.
Regardless of what approach you use, however, it is imperative that you SSL protect, at minimum, the sign in page. This is the page where a user enters his credentials. If that page is not being accessed over SSL then the user's credentials will be sent over the Internet in plain text.
would [Membership, Roles, etc.] give me the ability to assign users access to certain pages directly and at the same time through Roles (that group access definition to multiple pages)
URL authorization allows you to lock down an entire page based on the user/role. To grant access to particular features on the page you would have to write your own code/logic.
To learn these technologies, I will, shamelessly, recommend that you check out my tutorials on website security. There are a total of 15 step-by-step tutorials in both C# and VB with complete, tested, working demo code you can download. They cover the gamut of user account-related scenarios, from forms auth to URL authorization to role-based authorization to creating and managing user accounts.
Here is the URL again: http://www.asp.net/security/tutorials
Happy Programming!
Maybe you should look at asp.net membership provider:
http://msdn.microsoft.com/en-us/library/yh26yfzy.aspx
Everything is there and highly customizable
Using Apache, it is quite simple to set up a page that uses basic access authentication to prompt a user for a name/password and use those credentials in some way to grant access to that user.
Is this secure, assuming the connection between the client and server is secure?
The worry about basic auth is that the credentials are sent as cleartext and are vulnerable to packet sniffing, if that connection is secured using TLS/SSL then it is as secure as other methods that use encryption.
This is an old thread, and I do not believe the highest voted/chosen answer is correct.
As noted by #Nateowami, the security stack exchange thread outlines a number of issues with basic authentication.
I'd like to point out another one: if you are doing your password verification correctly, then basic authentication makes your server more vulnerable to denial of service. Why? In the old days, it was common belief that salted hash was sufficient for password verification. That is no longer the case. Nowadays, we say that you need to have slow functions to prevent brute forcing passwords in the event that the database becomes exposed (which happens all too often). If you are using basic auth, then you are forcing your server to do these slow computations on every API call, which adds a heavy burden to your server. You are making it more vulnerable to DoS simply by using this dated authentication mechanism.
More generally, passwords are higher value than sessions: compromise of a user password allows hijacking the user's account indefinitely, not to mention the possibility of hijacking other systems that the user accesses due to password reuse; whereas a a user session is time-limited and confined to a single system. Therefore, as a matter of defense in depth, high value data like passwords should not be used repeatedly if not necessary. Basic authentication is a dated technology and should be deprecated.
The reason why most sites prefer OAuth over Basic Auth is that Basic Auth requires users to enter their password in a 3rd party app. This 3rd party app has to store the password in cleartext. The only way to revoke access is for the user to change their password. This, however, would revoke access for all 3rd party apps. So you can see what's the problem here.
On the other hand, OAuth requires a web frame. A user enters their login information at the login page of this particular site itself. The site then generates an access token which the app can use to authenticate itself in the future. Pros:
an access token can be revoked
the 3rd-party app can not see the user's password
an access token can be granted particular permissions (whereas basic auth treats every consumer equally).
if a 3rd-party app turns out to be insecure, the service provider can decide to revoke all access tokens generated for that particular app.
Basic auth over http in an environment that can be sniffed is like no auth, because the password can be easily reversed and then re-used. In response to the snarky comment above about credit cards over ssl being "a bit" more secure, the problem is that basic authentication is used over and over again over the same channel. If you compromise the password once, you compromise the security of every transaction over that channel, not just a single data attribute.
If you knew that you would be passing the same credit card number over a web session over and over, i'd hope that you'd come up with some other control besides just relying on SSL, because chances are that a credit card number used that frequently will be compromised... eventually.
If you are generating passwords with htpasswd consider switching to htdigest.
Digest authentication is secure even over unencrypted connections and its just as easy to set up. Sure, basic authentication is ok when you are going over ssl, but why take the chance when you could just as easily use digest authentication?
As the name itself implies, 'Basic Authentication' is just basic security mechanism. Don't rely on it to provide you with worry free security.
Using SSL on top of it does makes it bit more secure but there are better mechanisms.