Develop Reference

UserPrincipal.FindByIdentity error in Firefox

I have a method to retrieve a list of AD groups that a user belongs to. Here is the code:
public static List<GroupPrincipal> GetGroups(string userName)
{
List<GroupPrincipal> result = new List<GroupPrincipal>();
// establish domain context
PrincipalContext yourDomain = new PrincipalContext(ContextType.Domain);
UserPrincipal user = null;
// find your user
user = UserPrincipal.FindByIdentity(yourDomain, userName);
// if found - grab its groups
if (user != null)
{
PrincipalSearchResult<Principal> groups = user.GetGroups();
// iterate over all groups
foreach (Principal p in groups)
{
// make sure to add only group principals
if (p is GroupPrincipal)
{
result.Add((GroupPrincipal)p);
}
}
}
return result;
}
In both IE and Chrome, this can work fine, but in Firefox, it always gives me DirectoryServicesCOMException on the user = UserPrincipal.FindByIdentity(yourDomain, userName); I don't even have any idea what kind of exception that is. Can someone explain me what the error is and how to fix it? Thank you so much!

Change the call to look like this:
using (HostingEnvironment.Impersonate()){
user = UserPrincipal.FindByIdentity(yourDomain, userName);
}
You will need to make sure that your application pool has AD permissions. This will perform the underlying AD call using the credentials of the hosting environment (the web App Pool Identity) instead of the credentials of user, who may not have permissions to query the AD server.

Get domain chosen by PrincipalContext

I'm creating a custom login functionality for asp.net which validates against active directory. The user must be able to login with only his username or with his username and a domain (and a password in both cases).
Code:
AuthUser user = Authentication.getDomainAndUserName(givenUsername);
bool validAccount = false;
PrincipalContext network = null;
if (user.domain != "") network = new PrincipalContext(ContextType.Domain, user.domain);
else network = new PrincipalContext(ContextType.Domain);
if (UserPrincipal.FindByIdentity(network, IdentityType.SamAccountName, user.username) != null) {
validAccount = network.ValidateCredentials(givenUsername, givenPassword, ContextOptions.Negotiate);
}
The "AuthUser" contains the username and, if given, the domain. Now if a user didn't explicitly specify the domain the above still works fine.
So if you call
new PrincipalContext(ContextType.Domain);
It seems that the domain is set automatically.
In that case, how can i find out the domain it used?

You always can get the domain used from the user principal returned from UserPrincipal.FindByIdentity()

Authenticating another user when using Windows Authentication

I have a .NET MVC 4 application that uses Windows authentication. Some users are administrators, and need to be able to enter data on behalf of other users.
I have a text box where the admin enters the name of another user. How can I check to verify that the text entered is an existing Windows username?

You could use the FindByIdentity method:
string username = "Some username you retrieved from the TextBox";
using (var ctx = new PrincipalContext(ContextType.Domain, "YOUR_DOMAIN"))
using (var user = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, username))
{
bool userExists = user != null;
// here you know whether the user exists or not
}

You can query the Active Directory of your organization for this.
DirectoryEntry entry = new DirectoryEntry("LDAP://DomainName");
DirectorySearcher Dsearch = new DirectorySearcher(entry);
String Name="Richmond";
dSearch.Filter = "(&(objectClass=user)(l=" + Name + "))";
See this article:
http://www.codeproject.com/Articles/6778/How-to-get-User-Data-from-the-Active-Directory

UserPrincipal from Active Directory

I have problem with getting UserPrincipal from Active Directory. First of all I have used on my local environment (using not IIS but ASP.NET development Server):
User usr = new User();
usr.SoeId = Request.ServerVariables["LOGON_USER"];
usr.IP = Request.ServerVariables["REMOTE_ADDR"];
usr.FirstName = UserPrincipal.Current.GivenName;
usr.LastName = UserPrincipal.Current.Surname;
And it works fine. I got what I want. But when I install application on testing environment I got error "Object reference not set to an instance of an object". I have tried solution from here.
using (PrincipalContext pc = new PrincipalContext(ContextType.Domain))
{
UserPrincipal up = UserPrincipal.FindByIdentity(pc, usr.SoeId);
return up.DisplayName;
// or return up.GivenName + " " + up.Surname;
}
But it does not work.
I use windows authentication. Impersonation is set to true. Please help me.

change the identity of your ApplicationPool to run using domain user.
in iis 6 right-click your application pool, go to Identity tab and set a domain user under which the pool will run.
in iis 7 right-click your application pool, select advance settings, under process model you'll find Identity, change it to use domain user.
you can also pass a domain user and pass to PrincipalContest Constructor
using (PrincipalContext context = new PrincipalContext(
ContextType.Domain,
"name of your domain",
"container of your domain",
"user#domain", //create a user in domain for context creation purpose.. this username will be constant.. you can keep it in app config
"password")){
UserPrincipal up = UserPrincipal.FindByIdentity(pc, usr.SoeId);
return up.DisplayName;
}
if your domain name is dom.com then your container would be something like DC=dom,DC=com and the user name should be given as user#dom.com or dom\user

Use this:
// find currently logged in user
UserPrincipal adUser = null;
using (HostingEnvironment.Impersonate())
{
var userContext = System.Web.HttpContext.Current.User.Identity;
PrincipalContext ctx = new PrincipalContext(ContextType.Domain, ConfigurationManager.AppSettings["AllowedDomain"], null,
ContextOptions.Negotiate | ContextOptions.SecureSocketLayer);
adUser = UserPrincipal.FindByIdentity(ctx, userContext.Name);
}
You must wrap any 'context' calls in HostingEnvironment.Impersonate

Find Users e-mail based on the current IPrincipal

I am using Windows Authentication in an ASP.net MVC application. I would like to query Active Directory to get a users e-mail address based on the current user:
IPrincipal principal = HttpContext.Current.User;
Is there a way I can use Active Directory to query for their e-mail address?

using (var context = new PrincipalContext(ContextType.Domain)) {
using (var user = UserPrincipal.FindByIdentity(context, userName)) {
if (user != null) {
return user.EmailAddress;
}
}
}