I've seen other answers saying how to secure virtual folders for Windows Authentication only. I would like to allow both anonymous AND Windows Authentication in IIS, but prioritise Windows Authentication over Anonymous Authentication. The reason for this is that the web app I am building needs to support anonymous access as well as privileged.
Is this possible? I.e. if Windows Authentication cannot authenticate against the domain, it will fall back to a generic identity, as opposed to the way it works out of the box by favouring anonymous access.
Developing on W7 with IIS.
You could do the steps in this article: http://msdn.microsoft.com/en-us/library/ms972958.aspx
And then just don't redirect to a login page. Basically you trap the authentication error and keep going.
Related
We are using Identity Server 3 in our tool that has the following structure. One (AngularJs) Spa with 10 Web APIs . We use the WindowsAuthWebHost mini project to do the windows handshake to get the windows(domain) identity of the user, based on which we build a complex(with custom claims) token that it's used by the client Web APIs. All the 10 Web APIs have anonymous authentication set in the IIS. And it works smoothly.
Now, we are trying to expose this tool outside the company network and a perquisite is to have windows authentication on all the Web APIs in the IIS. If we set this time of authentication, now all the calls are unauthorized.
Do you know if there is a way to keep the same flow, but also validated the windows authentication?
Windows authentication will not work outside of the network. The user needs to have a valid user account in your domain (username/password), or even a local account on your IIS server.
Note that NTLM doesn't work through some proxy servers, so this is one reason that Windows AuthN isn't used so much on the public internet.
To achieve your requirement you could use the form authentication with active directory.you may need to enable both form and anonymous authentication. then create deny authorization rule for anonymous users and allow rule for all users.
How To: Use Forms Authentication with Active Directory in ASP.NET 2.0
I'm trying to understand the IIS windows and anonymous authentications. is there any difference between below options,
Anonymous
Anonymous + windows
Anonymous authentication gives users access to the public areas of your Web or FTP site without prompting them for a username or password. By default, the IUSR account, which was introduced in IIS 7.0 and replaces the IIS 6.0 IUSR_computername account, is used to allow anonymous access
Windows authentication, Identifies and authorizes users on the server's user list. Access to resources on the server is then granted or denied on the user account's privileges. Windows authentication is best suited for intranet web applications. The advantage of Windows authentication is that the web application can use the exact same security that applies to your corporate network. username, passwords, and permissions are the same for network resources and web applications
If both anonymous and windows authentication is enabled in IIS, and if we don't have a deny entry or anonymous in the web config then the resources on the web server are accessed using anonymous authentication
As long as anonymous authentication is enabled, IIS uses it, no matter whatever else you configure.
I have a classic ASP Web application that's been running on a Windows Server 2003 server with IIS 6.0 for several years. I have to move it to a Windows Server 2008 server with IIS 7.0. I've got it working, but the ServerVariable LOGON_USER doesn’t get populated. This seems to be because I have enabled Anonymous Authentication and allowed Anonymous Authorization to the site. However, if I disable/deny either of those, then I get an Authentication or Authorization error when attempting to open it. I have to have the LOGON_USER variable for the program to work correctly, but no matter what combination of Authentication/Authorization I use, I get errored out if I don't allow anonymous login. Rather at a loss at this point as to what to try next. Any suggestions?
When you disable anonumous access, the site will become inaccessible for users that are not logged in.
You will need to add at least read-rights in Windows Explorer to the folder your web-application is running in.
If you do that, IIS will then prompt you for a username and password. You can use the credentials of the user you have assigned read rights to.
This will then authenticate you as that specific user, and allow you to run the site. This will also fill the LOGON_USER servervariable with the username of the user you added.
Here's some more documentation on how to create a user for access using basic authentication in IIS:
http://technet.microsoft.com/nl-nl/library/cc772009%28v=ws.10%29.aspx
http://msdn.microsoft.com/en-us/library/aa292114%28v=vs.71%29.aspx
How do I create a user account for basic authentication?
Please explain impersonation for non-technical users.Then please explain it in the context of ASP.NET. Is Impersonation good or evil? Do we use it in the case of Forms-based Authentication?
You should check out Keith Brown's description of impersonation. It is really a Windows concept.
When you have an application using forms authentication (FA) the IIS process is running under the credentials of a specific user setup in IIS.
Example: If you have a user called Bob logged on using FA and IIS setup to run as Network Service. Bob accesses a page which makes a web service call to another computer, the other computer will see the IIS user and not Bob. You can use impersonation to allow Bob to access the web service as a real Windows user and not Network Service.
Impersonation is not evil but it can be misused. You really need to understand the impact on your overall security model. It is also something that creates a lot of work for a developer to debug. This is especially the case if you do not have admin rights to the resource (eg. web service) you are trying to access.
Web applications run through a web server. That web server runs as a user with different permissions than yourself. Impersonation allows the application to run as you (or any other user with different priveledges on the cmoputer), as if you were logged in to the computer running it itself.
It actually makes things quite good. It allows you another way to grant/restrict access to protected files on the computer.
And yes, you can apply it using Forms Authentication (but you don't have to).
ASP.NET applications can execute with the Windows identity (user account) of the user making the request. Impersonation is commonly used in applications that rely on Microsoft Internet Information Services (IIS) to authenticate the user.
ASP.NET impersonation is disabled by default. If impersonation is enabled for an ASP.NET application, that application runs in the context of the identity whose access token IIS passes to ASP.NET. That token can be either an authenticated user token, such as a token for a logged-in Windows user, or the token that IIS provides for anonymous users (typically, the IUSR_MACHINENAME identity).
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).