Develop Reference

Unable to validate credentials using LDAP

I am new to LDAP and wanted to connect to a LDAP server using .Net to validate the user credentials. The following code returns an error:
The LDAP server is unavailable
But the validation works fine in Java code. Kindly let me know where I have gone wrong.
using (PrincipalContext pc = new PrincipalContext(ContextType.Domain, "LDAP://192.168.65.201:389/DC=be,DC=ndl,DC=CompanyName,DC=com"))
{
bool a= pc.ValidateCredentials("myname#CompanyName.com","password");
}

First of all - PrincipalContext only works against Active Directory, not against any other LDAP server.
Secondly: you're specifying invalid parameters for the constructor. Check out the MSDN docs on what constructors are available for PrincipalContext.
You can define just a ContextType parameter, in which case the PrincipalContext is constructed against the current domain you're connected to:
var ctx = new PrincipalContext(ContextType.Domain);
Or you can use a constructor with a second string parameter which signifies the domain name of your domain (only the domain name - NOT a complete LDAP path!):
var ctx = new PrincipalContext(ContextType.Domain, "CompanyName.com");
Then you're connected to that specific domain, at the root level.
Or thirdly, you can specify a third parameter which defines the container in that domain to connect to:
var ctx = new PrincipalContext(ContextType.Domain, "CompanyName.com",
"CN=Users,DC=be,DC=ndl,DC=CompanyName,DC=com");
So you'll need to find the appropriate constructor and supply the correct parameters to get this to work - if you're using Active Directory.

SimpleBind Authentication against Active Directory

I'm trying to authenticate login credentials against Active Directory (AD DS) using the following code:
using (var context = new PrincipalContext(ContextType.Domain, ipAddress))
{
Console.WriteLine("Connected to {0}:", context.ConnectedServer);
context.ValidateCredentials(username, password);
}
Where ipAddress is the address of the primary domain controller. However this gives the following error when attempting to read context.ConnectedServer:
System.DirectoryServices.DirectoryServicesCOMException (0x8007052E):
The username or password is incorrect.
In addition to this issue I have the following constraints:
The production environment may or may not be on the domain.
The clients do not want to enter any privileged credentials to query the directory.
Due to this second constraint I have tried to execute a SimpleBind, but without much luck:
using (var context = new PrincipalContext(ContextType.Domain,
ipAddress,
null,
ContextOptions.SimpleBind,
usernameToValidate,
password))
Based on these constraints, how can I authenticate against Active Directory?

I was able to authenticate using the following code:
using (var context = new PrincipalContext(ContextType.Domain, ipAddress))
{
// NOTE! Username must be of the format domain\username
return context.ValidateCredentials("domain\someuser", password, ContextOptions.SimpleBind);
}
The key part was to prefix the username with the short domain name. Once I did that, and specified SimpleBind in the call to ValidateCredentials instead of in the context constructor, it worked fine.

Unable to extract information

I'm trying to query a domain to determine if:
User is a valid user (and has the correct password)
User is enabled
User belongs to group x
My development machine does not belong to this domain.
I want to specify the username and password via my application
I'm using the System.DirectoryServices.AccountManagement namespace as this seems to be the most efficient way doing this, however I've struggling to get even the most basic of information out of my domain controller.
I can explore LDAP via another tool.
First test is to collect user information, the code below returns null on user.
The user however is valid.
What am I doing wrong?
// set up domain context
PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "server","CN=Users,DC=doom,DC=home", "ldapuser","password");
// get user contect
UserPrincipal user = UserPrincipal.FindByIdentity(ctx, IdentityType.Name, username);
//is user locked?
var locked = user.Enabled;
Update:
Having defined the bind method as below, I now receive error
"Information about the domain could not be retrieved (1355)."
var ctx = new PrincipalContext(ContextType.Domain, "server", "DC=doom,DC=home", ContextOptions.SimpleBind, "ldapuser", "password");

Sorted.
This answer resolves the two issues I came across when attempting to connect to a domain controller that I am not a member of.
This article get me the final answer:
http://elegantcode.com/2009/03/21/one-scenario-where-the-systemdirectoryservices-accountmanagement-api-falls-down/
you need to define the Bind in the context (i.e. ContextOptions.SimpleBind)
You must set up the domain server in your Network adaptors DNS settings as the first DNS server to use.
I can now connect to my AD and collect data.

Logon failure error when attempting UserPrincipal.FindByIdentity

I've been searching for solutions on this for a while now, but each thread a dead-end unfortunately.
I'm working on a C#/ASP.net web app that will only be used internally by our company. Anonymous access has been switched off both in IIS and my web.config file forcing IIS to use the windows authenticated user (Active Dir user).
My problem is that the following code works perfectly to get the required (or any) AD user:
using System.DirectoryServices.AccountManagement;
... other code ...
PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "mydomain", "someADuser", "someADuserpassword");
UserPrincipal winuser = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, "samaccountname");
"someADuser" used in the PrincipalContext above is the current logged in user through windows, thus authenticated and a valid AD user. Using the following code (with the exact same user still logged in) gives me a "Logon failure: unknown user name or bad password" error:
PrincipalContext ctx = new PrincipalContext(ContextType.Domain, "mydomain");
UserPrincipal winuser = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, "samaccountname");
It seems UserPrincipal.FindByIdentity doesn't use the logged in user's validated credentials for some reason if it's not specified in the PrincipalContext object - something I don't want to do.
Is it possible that the ctx aren't picking up the logged in Windows users for some reason, even if the necessary settings (i hope) is added to web.config :
<authentication mode="Windows"/>
<authorization>
<deny users="?"/>
</authorization>
And Anonymous access is completely disabled in IIS?

It seems UserPrincipal.FindByIdentity doesn't use the logged in user's validated credentials for some reason if it's not specified in the PrincipalContext object - something I don't want to do.
UserPrincipal.FindByIdentity doesn't care about the user's credentials at all. You're just performing a look up to see if the account exists. The reason you're getting an error is because the default user credentials (i.e. the identity that your web application is running as) doesn't have access to the directory, so it can't perform the look up. When you pass in the client's credentials to the PrincipalContext then the problem goes away because your client has a valid AD account with access to the directory.
You should investigate which identity is being used to run the application pool and make sure it has access to the directory.

Quite annoying as I though if anonymous access was turned off, the current principal would default to the user logged in to windows. It turns out it's not as indicated by #RogerN.
Using the following statement as mentioned by #TheKingDave, it basically impersonates the user logged in to windows and makes the current thread run on it's principal rather than the "ASP" (in my case) account.
Because all the users on our domain has query/read access to Active Directory, this shouldn't be a problem to get more detail on them, which is what I wanted in the first place.
The end code (was testing):
System.Web.HttpContext.Current.Request.LogonUserIdentity.Impersonate();
ctx = new PrincipalContext(ContextType.Domain, System.Net.NetworkInformation.IPGlobalProperties.GetIPGlobalProperties().DomainName);
UserPrincipal winuser = UserPrincipal.FindByIdentity(ctx, IdentityType.SamAccountName, "whicheveraccount");
Hope it helps some1 in future! thx! ;-)

I did a lot of search/research to resolve the issue, but nothing worked, at last, all what I did was to add # to the servername, container, username & password like below:
app.CreatePerOwinContext(() => new PrincipalContext(ContextType.Domain, #"abc.net", #"OU=Customers,DC=abc,DC=net", ContextOptions.SimpleBind, #"abcnet\authuser", #"!$%MyPassword"));
And it worked. doh!

So I found out how to pass the impersonated identity. I had a situation where, as an admin, I wanted to unlock a user account automatically. I had to get the user names into variables and pass them in to the function like this:
string accountname = #"domain\username";
string admin = "adminusername";
string domain = Environment.UserDomainName;
string password = "password";
string dc = "WIN2K8DC1"; // example host name of domain controller, could use IP
// This determines the domain automatically, no need to specify
// Use the constructor that takes the domain controller name or IP,
// admin user name, and password
PrincipalContext ctx = new PrincipalContext(ContextType.Domain, dc, admin, password);
UserPrincipal winuser = UserPrincipal.FindByIdentity(ctx, accountname)
if (winuser != null)
{
WindowsImpersonationContext wic = Impersonation.doImpersonation(admin, domain, password); //class/function that does the logon of the user and returns the WIC
if (wic != null)
{
winuser.UnlockAccount();
}
}
Impersonation class functionality that can be used to return a WIC can be found on MSDN:
https://msdn.microsoft.com/en-us/library/w070t6ka(v=vs.110).aspx

Active Directory, enumerating user's groups, COM exception

while enumerating current user's groups through AD .NET API I sometimes get
COMException: Unknown error (0x80005000)
Here's my code :
var userName = Environment.UserName;
var context = new PrincipalContext(ContextType.Domain);
var user = UserPrincipal.FindByIdentity(context, userName);
foreach (var userGroup in user.GetGroups())
{
Console.WriteLine(userGroup.Name);
}
What's the problem? I thought every user can retrieve list of HIS groups?It seems to be strange behavior, sometimes It can be reproduced like this : when running on 'userA' PC, It crashes, but it is enumerating OTHER 'userB' groups successfully (under 'userA')!

Try using
var context = new PrincipalContext(ContextType.Domain, "yourcompany.com", "DC=yourcompany,DC=com", ContextOptions.Negotiate);
With the ContextOption set to Negotioate the client is authenticated by using either Kerberos or NTLM so even if the user name and password are not provided the account management API binds to the object by using the security context of the calling thread.

I had the same problem, I solved it by supplying the domain name when creating the PrincipalContext:
var domain = new PrincipalContext(ContextType.Domain, Environment.UserDomainName);
var user = UserPrincipal.FindByIdentity(domain, Environment.UserName);

0x80005000 = E_ADS_BAD_PATHNAME so you supply an invalid adspath somewhere, maybe you must add LDAP:// prefix or opposit are doing this twice? Set a breakpoint and inspect value...
EDIT:
AdsPath should be a value like "LDAP://CN=Administator,CN=Users,DC=contoso,DC=com", you seem to have a misformed path.