Searching for the user michael#mycontoso.com with the objectSid S-1-5-21-1234567890-123465789-123456789-123456, I only find a Foreign Security Principal CN=S-1-5-21-1234567890-123465789-123456789-123456,CN=ForeignSecurityPrincipals,DC=contoso,DC=com.
That foreign security principal does not contain the properties I have to read, so I guess I have to access the "Home AD" of that FSP.
Does a FSP have a property that always contains the LDAP path of the user object?
Is there a standardized/recommended way how to access the Home AD?
Sadly FSP don't contain the LDAP path of the referenced object.
(if it contain one, then it needs to be replicated once the object is rename/moved)
There seems no easy way to get back the containing AD using the SID from foreign forest.
If in local forest you may do it by binding to LDAP://<SID=S-1-xxxxx>.
A not-so-easy way is to build a domain SID to domain map.
Walk through each domain in trusted forests and build the map using the script here (the "The Script Solution" section).
https://learn.microsoft.com/en-us/archive/blogs/ashleymcglone/powershell-sid-walker-texas-ranger-part-3-exporting-domain-sids-and-trusts
SID of security principals are in the form of <domain SID>-<RID>.
e.g. domain SID of S-1-5-21-1234567890-123465789-123456789-123456 is S-1-5-21-1234567890-123465789-123456789.
By extracting the domain SID (if in .NET you can do it by using SecurityIdentifier class and the AccountDomainSid property) and the map then you can find out the containing domain.
You may try to retrieve the msDS-PrincipalName:
ldapsearch <options> -b "CN=ForeignSecurityPrincipals,DC=contoso,DC=com" "CN=S-1-5-21-1234567890-123465789-123456789-123456" msDS-PrincipalName
FOO\michael#mycontoso.com
Otherwise, the approach is as https://stackoverflow.com/a/27038494/10408280 describes:
Retrieve Domain identifier from first part of SID
Perform a lookup against that domain for the SID of the user or by sAMAccountName
Related
So... this question is maybe not solely a programming question but I hope one of you can shed some light on my issue:
The base need we have in our software is to query the groups a user is associated too with
LDAP. For this task we actually use parts of LDAP Admin to query the user. Actually we want to query for the UserPrincipalName which at least to my knowledge is the most common way right?
So.. our problem is that the AD is setup such that the user has an UPN like foo#HUS
but the user actually is bound to the domain HUS.adomain.com (aka LDAP base: dc=HUS,dc=adomain,dc=com) and searching using an UPN like foo#HUS.adomain.com does not work - only foo#HUS works. So... the question is:
Is this common?
And is there a name/resource for that?
(sorry I'm quite new to that all...)
The goal would be to use as less parameters in the administration tool as possible
aka only the base (and form from the base the UPN username).
Update: I found at least one resource (in German) that states that this is possible but not recommended by Microsoft for Azure AD. (aka having a different mail address than UPN )
When you initiate a LDAP search using a UPN like foo#HUS.adomain.com it wont work because this value is not present in the userPrincipalName value. When you search for a user by building its UPN using all the domain suffix available in the forest, then you would not consider searching the userPrincipalName attribute.
It is very difficult to build every constructed attribute from base for querying because every Active directory environment would be different. As you have mentioned that you would like to build the attribute from base, it may work if this is the only AD infra that you are targeting. Every AD infra would have its own ways in which it will be setup.
However if you would want your tool to work in any AD environment you would have to consider some other parameters.
UPN is a editable attribute . An organization can set it up or can create a user without a UPN value. Below is example of user created programmatically by using old ADSI libraries. You can repro the same by removing any users userprincipalName attribute value and the user logon account name as shown in the pictures below.
UPN is an optional attribute and a user account can be present in AD without it as well. Coming back to your specific environment in this environment only foo#HUS works because "HUS" might be setup as a valid domain suffix within the Active directory. You can check this by opening the domain.msc console on any domain controller or a machine with Remote Server Administration Tools installed. You would find the UPN suffix as shown below . I changed it in my environment as shown below.
The value you will add will now show up in the . If you remove HUS from here for example any existing user who have user#HUS userPrincipalName populated will get removed because this is a optional constructed attribute in AD. And you will have to setup this for all the users in the environment . For example check below after I changed the username to dh # HUS .
The userprincipalName value also got populated with the same.
Hope this helps clarify your query and understand more on how to use the native Active directory tools to understand more while you develop your custom LDAP search functionality/tool.
I was not able to find any info on this. Can a user from any AAD domain have the same Object Id as a user from any other domain. Or are these unique across all domains in Azure?
EDIT: Is there a validation process in Azure that checks if a GUID has already been used for the same type of object, such as a RID Master in Windows AD..
Yes, all of the users in Azure has an unique object id no matter where the user comes from because the object id is GUID format, GUID is Globally Unique Identifier, it will generate an unique GUID for each user when add a user to Azure AD.
By the way, there could be two same object id(guid), but it's a very small probability(very very small, for example if you have 100,000,000 users in all of your AAD domains, the probability of exist two same object id is about 1/3.4×10^30, so we can ignore that).
I've been looking for a way to identify a user in Active Directory without fail. I found this article which explains which fields are unique. It's a good starting point, but doesn't identify which fields are non-mutable. Further google queries result in AzureAD results on immutableId, which is what I want, but for regular AD. The case I'm trying to prevent is I use sAMAccountName (which is unique) to identify a user, but an admin decides to change the sAMAccountName for some reason (perhaps for uniformity) and I identify the same old user (with now a new sAMAccountName as a new user.
A few contenders from the article:
DN
UPN
sAMAccountName
ObjectGUID
Is there anything I'm missing? Is there an immutableId equivalent in pure AD (Not AzureAD)?
What you likely want is objectGUID. As "GUID" suggests, it is "globally unique". It doesn't change, even when the account is moved to another domain.
There is also objectSid (SID = Security Identifier), which is what Windows permissions use (the SID is stored in the permissions). It is also globally unique, but part of the SID is the SID of the domain. So if the account is moved to another AD domain, a new SID is generated on that domain, and the old objectSid is put in the sIDHistory of the new account.
There is some extra reading about that here: Security identifiers and globally unique identifiers
The distinguishedName changes whenever the account is renamed or moved to a new OU.
As you noted, both userPrincipalName and sAMAccountName can change too.
I want to know the best practice for authenticating users using OpenLDAP. I could perform a search using the cn.
But then what if I got multiple hits with similar cn (under different ancestors of course) and they all use the same password?
I tried to use uids but then I got some types of accounts that do not use uids (like mail accounts and the admin cn). Also, when I added some users under the admin cn (which has no uid) I could not login with the admin cn.
What is the unique key that identifies a user?
Note: I am using phpldapadmin to manage the active directory, and openldap for the c++ code.
You can configure your OpenLDAP server to perform the uniqueness check on your chosen attribute. CN is not the most favorable attribute to choose for uniqueness I would choose UID attribute and have a policy in place for username generation.
I'm trying to get user GUID from Active Directory. My code:
DirectoryEntry entry = new DirectoryEntry("WinNT://DOMAIN/UserName");
Console.WriteLine("The GUID of the ADS object:" + entry.Guid);
Console.WriteLine("The Native GUID of the ADS object:" + entry.NativeGuid);
The code above always returns d83f1060-1e71-11cf-b1f3-02608c9e7553, regardless of the user and domain.
Is it possible to get user GUID using WinNT protocol?
Check out Richard Mueller's Hilltop Lab where he has lots of spreadsheets showing all the properties the various providers expose. In particular, his list of properties that the WinNT provider exposes shows that there's no such things as a user's "GUID" or OID or anything like that exposed.
Mind you - the WinNT provider is only used for backward compatibility, and really only works well on local machine accounts.
If you want to access DOMAIN accounts, you should by all means use the LDAP provider instead - it'll give you access to all the LDAP properties on a user account.
Marc
Perhaps you mean SID (security identifier). Like a GUID it is unique, at least across the domain tree. I think the property is "objectSid". It's binary (byte[]). I can't remember how big it is (28 bytes?) but I'm pretty sure it's not a GUID.