I have a website with a large user base configured with asp.net 2.0 forms authentication. Before the user logs in via forms authentication is it possible to retrieve the windows login name/user account name on the machine they are using?
Many thanks
It certainly is possible--by adding another web application to your system. Here's roughly how I have done it:
Your primary web app uses Forms authentication. On the forms login page, any user that is determined to be on the local LAN (check IP address), redirect them to another app that uses Windows authentication. In this second app, you can determine the user (assuming the browser is configured to send credentials automatically to the zone in which your app resides), then set a cookie which your first app can read, and redirect the user back to the original app.
This does work.
This would only be possible if you were using Windows Authentication in your web application and then only if the user had logged in.
The kind of information you are after is not sent as part of the web request (quite rightly) and is therefore unknown to the web server.
Unfortunately no - if the user has not logged on, they are browsing anonymously, and are therefore unknown to the server. There is no way to identify them.
Once they're logged on, if you're using impersonation use WindowsIdentity.GetCurrent().Name. However, for forms authentication there's no direct way to ask the browser for their Windows credentials as they may not even be running Windows!
Not BEFORE no (not from the server).
Depending on the type of Auth you use, though, and the way the site is configured, you CAN get them to log in with their windows details.
See Mixing Forms and Windows Security in ASP.NET on Microsoft's MSDN.
The main difference with #TheObjectGuy answer is that instead of using 2 websites, this does all in a single website by configuring IIS to use the Integrated Windows authentication just in a "single" page (WinLogin.aspx).
Related
I need to implement something like Single Sign On for a application that is being used on both Intranet and Internet.
Now , the application uses its own table for storing User information and has more users than that present in the AD for the Company. Example contract workers/3rd party vendors etc and hence many users who don't belong to the Active directory of domain are listed in the User Table.
The Application is a bit old and currently it uses Form to authenticate the users.
But strangely authentication mode in the web.config file has the following entry for authentication. <authentication mode="None" />
I changed the authentication mode to Windows in web.config and in IIS 6 selected integrated Windows authentication and unchecked the anonymous access.
Now I have following two scenarios.
#1 Intranet
User logs in to the system using the System Credential which is stored in a AD
Now if user hits the link for the web application he should be logged in.
I have implemented this part by using Page.User.Identity.name in the Page load of login.aspx to check if the user exists in the DB.
#2 Internet
If I check it from a external network the browser prompts me for credential.
The requirement is that the user should not be prompted for credential instead should be shown the current Login page
I googled and ended up on stackoverflow every time. Sadly the solutions did not work out for me.
I stumbled upon this post by Scott Enabling Windows Authentication within an Intranet ASP.NET Web application and if you check the comments Scott refers to use of solution by commenter ripster in case application is accessed from internet as well as intranet. Though it didn't work out for me or may be I didn't do it properly.
It seems you require a mix of Windows and Forms authentication : The requirement is that the user should not be prompted for credential instead should be shown the current Login page
Thought to share this . May be it can help you as mostly I have seen people to like the second below mentioned solution a lot. ( Atleast when they read it.)
If you're in classic mode - you can have both Windows and Forms authentication. An alert will pop up
Challenge-based and login redirect-based authentication cannot be used
simultaneously
you can however ignore this warning. CarlosAg says that:
we decided to leave it there was because it is still behavior that many user
scenarios would be consider incorrect, since most of the time forms
authentication uses anonymous authentication and not windows.
Read here.
Now when you want to use integrated mode, This stack question : iis7 Challenge-based and login redirect-based authentication cannot be used simultaneously leads to this famous link: http://mvolo.com/iis-70-twolevel-authentication-with-forms-authentication-and-windows-authentication/, which allows to change the authentication way for a page.
Another way you can manage this when using windows authentication is to manage usernames using code:
string user = Request.ServerVariables["LOGON_USER"];
Refer this link: http://beensoft.blogspot.in/2008/06/mixing-forms-and-windows-authentication.html , which gives a different way of mixing Forms and Windows authentication.
This will probably turn out to be a doozie.
I'm developing an application in ASP.NET to be put on our company's intranet site. I've been handed a specification in regards to security and have no idea how to do it.
First part: The application is to use Windows Authentication. This part seems easy enough; I opened IIS in Administrative Tools, right clicked the node of my website, properties and checked 'Integrate Windows Authentication'. However, I have no idea how I will govern which people have access to my site. I'm thinking this should be taken care of at the database level. This is Q#1
Second part -- I have to implement a process for the following scenario: User 'Jane' can log in to our network, but does not have rights to my application. User 'Bob' does have rights to use my application. Bob needs to be able to sit at Jane's computer (under her network account), but be able to enter his credentials into my application and use it (even though Jane is logged into the local machine and network). This is Q#2
Any help, general direction, or advice would be appreciated. The winning lottery numbers would be appreciated even more.
Thanks,
Jason
You're looking for Windows Authentication and Authorization in ASP.NET
How To Use Windows Auth in ASP.NET
Authentication/Authorization Explained
How To Implement Windows Auth in ASP.NET
Part 2...you're right, that's tough. You'll need to roll your own custom security provider.
You'll have a login page, then check that against Active Directory yourself. From MSDN
ASP.NET also supports custom solutions
for using Windows authentication,
which bypasses IIS authentication. For
example, you can write a custom ISAPI
filter that checks the user's
credentials against Active Directory.
With this approach you must manually
create a WindowsPrincipal object.
You've got requirements around authentication and authorization here.
Authentication: The act of confirming identity
Authorization: The act of correlating an identity to a privilege (eg Read/Write/Delete)
Windows Authentication is useful if you want "auto-signon" capability. The site will "know" the user by ID without them having to sign in.
The need for users to login from multiple locations means that you must implement a login page. This would fulfill your requirement in which one user may sit at another's workstation and log in.
You will want to authenticate users against the Windows domain. This can be done with a custom membership provider. Here's a walkthrough:
http://msdn.microsoft.com/en-us/library/ms180890(v=vs.80).aspx
This will allow you to present a login page that will authenticate users with their domain username and password. This will authenticate users- the identity of the user will be stored in the HttpContext.User. You can then also maintain a user list in a database to store authorization data.
Also found this -- a pretty good resource for anybody out there who's in the same boat:
Mixing Forms and Windows Security in ASP.NET
http://msdn.microsoft.com/en-us/library/ms972958.aspx
I'm looking for a way to pass some sort of credentials or Authorization token from a VB.Net Client to an ASP.Net web application that allows the Client to auto-login to our Forms-Authenticated website. If a user is logged into a local application, I want them to be able to view some web pages without having to login to the website as well. The credentials are not the same between the apps, but I would just like to pass some sort of encrypted token or key to the web page so I know they are coming from the desktop application. Is this possible without requiring a username and password login?
I also need to make sure this URL that is used cannot be simply copied and used from another location, so I'll need to include some sort of information in the encrypted value to know where it's coming from.
I know how to login the user with Forms Authentication and all that, just need to figure out the best way to secure this. Thanks!
OAuth is commonly used to allow desktop applications to access a user's private data on a web site. Since you're using .NET, I suggest you check out DotNetOpenAuth which includes sample OAuth web sites and client applications. It allows for this secure token to be passed that can tell your web site that the desktop app is the one making the requests and (usually) whose data is being accessed.
The best part about the OAuth solution is your desktop app never has to ask for the user's credentials. No credentials are in the URL. And if the desktop application is ever compromised (perhaps by the computer being stolen), the web site can kill the secure token the desktop app was using to cut off access without requiring the user to change their password.
You might want to look into issuing client-side certificates for these applications. Basically, you generate a certificate that you install with the client application and then on the server side, you check the ClientCertificate property of the HttpRequest instance exposed by the Request property on the current context.
Note that what you are doing is really a very bad idea, in that applications should never be assigned identity, only users. To that end, you should be authenticating each and every user that is using your app, not considering the application to be the identity. It's commonly considered a bad practice to do such a thing.
You can share credentials between the applications using ASP.NET Client Application Services.
Here are some resources:
Client Application Services
Client Application Services with Visual Studio 2008
Is your desktop app running on machines that are in the same domain as your web server (i.e. all in the same company)? If so, Integrated Windows Authentication is your easiest solution.
I think its best idea to use a web browser control inside the desktop application .
Then use the WebBrowser1.Document most probably
WebBrowser1.Document.Cookie
get if the user is singed in.
I also need to make sure this URL that
is used cannot be simply copied and
used from another location, so I'll
need to include some sort of
information in the encrypted value to
know where it's coming from.
If you store the encrypted value in a cookie or as a field in a form (POST request), then the credential is no longer in the URL and so it can't be easily copied (note that I said "easily").
Inside my ASP.NET application, I would like to add an iframe where I can display the emails from our exchange server for the logged in user. The web application uses forms authentication with custom authentication (passwords are hashed and stored in db).
Is there a way to show OWA within my web app without prompting the user for password (OWA uses windows authentication)? Can I use impersonation in some fashion or establish a trust between my IIS server and the server running OWA?
Has anyone tried this before?
If you are using an iframe for that, then it is a separate process in terms of authentication. Requests from the iframe are sent to OWA server just as you had opened the page in full screen.
However, it is possible to configure your Exchange server to allow windows authentication, see here: http://support.microsoft.com/kb/300656
This way you will authenticate with windows forms authentication to your web application and with windows auth to the OWA server.
I think you would have to have the Windows authentication be the authentication source for the website - or at least map accounts in the website to accounts in OWA
DNN does something a little like this with its Active Directory security provider. Might look at the source of that for some ideas - http://dnnauthad.codeplex.com/
I am in the process of writing an application that will need multiple forms of authentication.
The application will need to support authentication to Active Directory, but be able to fail back to a SQL Membership Provider if the user is not in Active Directory. We can handle the failing to the SQL Provider in code based on the username provided because the username will be a different format than the Active Directory username.
Is this even possible? What I mean is, can I use membership and use both ActiveDirectoryMembershipProvider and SqlMembershipProvider together or will I have to roll my own?
Another additional added complexity is that I would like to automatically authenticate my internal users based of Windows Authentication back to AD, but use Forms Authentication for users not on our internal network, or users that are using the SQL Provider.
These will most likely be separate servers, one internal, and the other external so I have a lot of planning to do to figure out the data replication, and how I will authenticate the AD users if they hit the outside server etc.
I am wondering what thoughts are out there as I start down this road. Is what I am wanting to do even possible without me rolling my own, or is there a way to mesh these together?
Thanks for the reply.
The reason I asked originally was because I was able to get this specific senerio working about 7 years ago using IIS to authenticate and then passing back the credentials to a Lotus Domino Server Web App. If the user was not authenticated via the Windows Authentication/ISS then Domino would handle the authentication. This was what I was looking to do here, but really couldn't think of a way to make it work in IIS.
As for the rest of your reply, I think you are on to the way that I will need to take. I have thought this through and tossed it around in my head a lot. The application will be somewhat different on the two servers anyway since there is going to be limited access to the data on the external server anyway. The fact that so much is going to be different already I may just treat these as two applications, thus negating the need to use two types of authentication in the same application anyway.
I am playing around with the idea already of writing my own authentication/login window for the external server, and if the user trys to log in with their AD credentials on the external server I will be able to detect that and redirect them to the internal server. If they are not on the local network or VPN'd in they will simply not get access. This part still has some thought process to go though so I am not sure.
As an additional thought - is there a way to pull just enough of AD into a SQL database to allow me to authenticate users to the SQL database from the external server using their AD credentials, without creating any security issues? I hope I am clearly typing what I am thinking....
Thanks again!
Tim
This is the way I've handled a similar situation based on this info:
Configured the application to use Forms authentication.
Set the LoginUrl to a page called WinLogin.aspx.
In WinLogin.aspx, use Request.ServerVariables["LOGON_USER"] to get the username then call FormsAuthentication.RedirectFromLoginPage( authorizedUserName, false ) to log them in. I guess you can manually check Active Directory as this point as well.
Create an html page that redirects to a page called Login.aspx
Login.aspx is your standard username/password login.
In IIS, Enable Integrated Authentication and Anonymous on the entire site, but deny anonymous access to WinLogin.aspx.
In IIS, set your 401 errors to the page created in step 3.
What basically happens is that when an unauthenicated user hits the site, they're redirected to WinLogin.aspx. Since anonymous is turned off, integrated security makes a check. If that passes, your custom code in WinLogin can run. If the integrated security check fails, a 401 error occurs. Your custom 401 page redirects to Login.aspx where the user can log in using their username and password with the SQL provider.
As far as I know, Web Applications are configured to use either Windows Authentication or Forms Authentication, but not both. Therefore, I do not believe it is possible to automatically authenticate internal users while requiring others to enter a username / password.
You could authenticate to Active Directory or a SQL user store via Forms authentication by using a custom provider. However, the AD users would still need to enter their username and password. Although I've never combined these two methods, I have used Forms authentication to authenticate against both sources at one time or another.
With that said, I think you may want to consider reducing the "flexibility" of your system. If you have an external facing server and an internal facing server, you could simply change the provider configuration on each copy of the application to go against a different source. Then, you could configure the internal one to use Windows (automatic) authentication and the external one to use Forms authentication.
IMHO, I believe that internal users should not be using the external server to access the application. If they are, they should have a user account stored in SQL, completely separated from their AD account. Basically, when someone accesses the application externally, they are acting as an external user, irregardless of their physical location.
Well, it is possible to use ActiveDirectoryMembershipProvider and SqlMembershipProvider, but this requires you design your log on page with your own code instead of the Login controls.
About the mix authentication (Windows and Forms), as far as I know only IIS 7 makes it easy and clean. See this post for details,
http://mvolo.com/blogs/serverside/archive/2008/02/11/IIS-7.0-Two_2D00_Level-Authentication-with-Forms-Authentication-and-Windows-Authentication.aspx