How to authenticate in LDAP with C#

Question

Im very surprised because I have 5 years ago making LDAP connections but suddenly there is one which I can´t connect to ldap. The LDAP data are:

LDAP: LDAP://172.16.0.181:390/dc=asmet,dc=local
Username: cn=zentyalro,dc=asmet,dc=local
Password: EBsmOpCoIytamGe=Yret

The next is the code that I'm using for authentication:

bool authentic = false;
try
{
    DirectoryEntry entry = new DirectoryEntry("LDAP://172.16.0.181:390/dc=asmet,dc=local",
        @"cn=zentyalro,dc=asmet,dc=local", "EBsmOpCoIytamGe=Yret");
    object nativeObject = entry.NativeObject;
    authentic = true;
}
catch (DirectoryServicesCOMException ex)
{
}

And the error is:

Invalid DN syntax specified.

Really I don't know why is happening this. The more strange thing is that with any LDAP explorer tool the authentication is possible, but in code not. Why?

Answer 1

I think it is because of your syntax. Try this code below:

bool authentic = false;

using (var context = new PrincipalContext(ContextType.Domain, "172.16.0.181:390", username  , password))
        {

            if (context.ValidateCredentials(username, password) == true)
            {
                authentic = true;
            }
}