I am trying to obtain all the user accounts from a particular Oraganizational Unit. I have the base dn, scope and filter as follows:
BASEDN "OU=dc users,DC=example,DC=com"
SCOPE SUBTREE_SCOPE
FILTER "(&(objectclass=user)(objectcategory=person))"
The OU I am searching, consists of sub OU's as well as groups. The problem is I am able to obtain all the user accounts in the sub OU's but
Iam not able to obtain the user accounts in the groups within the OU. Any idea why?
EDIT:
Also if i search a group which consists of sub groups, Iam unable to obtain user accounts in the sub groups as well. Is it not possible to apply sub tree search for groups?
In an LDAP directory server, entries have a type (based on the objectClass attribute). They are groups or users or organizational units... When you search, you are returned the entries that matches your filter. In your example, you are searching for entries of type users, not groups. You can change your filter to return both groups and users, but your code will need to parse the returned entries to detect the type and what to do with them.
Related
I'm trying to make a query that outputs all the groups (and nested groups) that a user is part off, queried for by sAMAccountName value.
For example, the following query works and gives the expected output but uses the displayname instead.
(&(objectCategory=group)(member:1.2.840.113556.1.4.1941:=cn=Tester,ou=people,dc=Windomain,dc=local))
Simply changing "cn" to "sAMAccountName" doesn't work (I did verify that the sAMAccountName value is correct)
Is it possible to do this with LDAP queries?
There are a couple of options to display the complete group membership of a user, including all nested groups.
The simplest method is to query the TokenGroups attribute of the user object. This is a constructed attribute, that will return all the SIDs of the groups that will be added to the user's access token when the user authenticates. The only condition for the constructed attribute, the search scope must be Base scope for the attribute to be returned.
The LDAP_MATCHING_RULE_IN_CHAIN (1.2.840.113556.1.4.1941) matching rule is limited in its functionality, it will only return the groups that the user's DN has been added to the member attribute of the group, so some nested groups will not be included in the query.
The other option is to use a 3rd party tool to return the nested groups by transverse the groups membership to see the group membership. Such as NetTools User's membership option https://nettools.net/users-membership and the NetTools AD Properties dialog which includes the TokenGroups tab which will display the TokenGroups attribute with the SIDs resolved.
You can search for the user by the sAMAccountName and ask for the msds-memberOfTransitive attribute, which contains a recursive list of the distinguished names of the groups the user is a member of.
There is also the msds-tokenGroupNames attribute, which contains the distinguished names of all the groups whose SIDs appear in the tokenGroups attribute.
The difference is that tokenGroups only includes security groups, whereas memberOf includes distribution lists as well. Only security groups can be used to assign permissions.
Both are constructed attributes, so you have to specifically put it in the list of attributes to return in the search.
Sorry unable to add comments
Be careful of the msds-memberoftransitive attribute, it has some funky logic which doesn't follow the normal value ranging rules and can return incomplete results, see https://blog.joeware.net/2021/04/19/6068/
I'm trying to write a filter to get all the users of a given group in Active Directory.
To that end I have the following query
LDAPSearch("DC=test,DC=myorg,DC=com", "(objectClass=user)", 1, "name")
I'm a bit confused as to where I should give the name of the group on which to base the search on. As far as I know you cannot have two groups in AD with the same name.
In general, user objects have an attribute called memberOf that lists DNs of groups that a user is member of. Therefore you can search with a filter like (&(objectClass=user)(memberOf=<DN of requested group>)).
Please note that due to AD design, user's primary group is not included in memberOf attribute. For most users that group would be Domain Users (unless explicitly changed), but if changed, that group will no longer list in memberOf and this query will not find such user.
I have a LDAP searchquery where i am using the following filter
"(&(objectClass=user)(objectCategory=person))"
and running against AD in order to get User-accounts out. One of the attributes being returned ("memberOf") holds a ";" separated string of groups that user is a member of.
i.e.
CN=MyGroup,OU=MyMainOU,DC=masterdom,DC=local;
CN=Administrators,CN=Builtin,DC=masterdom,DC=local
I want to filter out the BuiltIn security groups, when processing the list can I rely on the "built in" groups containing the string "cn=builtin"? Or could it change with local etc. If so what is the correct method?
You if want to utilize the memberOf attribute, you can include it in your filter by using the full container name :
(&(objectClass=user)(objectCategory=person)(memberof=CN=Builtin,DC=masterdom,DC=local))
Something to keep in mind though, is that the memberOf attribute will only show groups native to the domain component (DC) in which the user is derived from - by that I mean, if user A is part of both the Developers and Management groups, but the Developers group doesn't exist within the current domain component you're querying, then the memberOf attribute will only show the Management group for the user when queried.
Plus, the memberOf attribute is a computed back-link attribute or a constructed attribute. It's maintained and calculated by Active Directory, so as you move users and groups around, that value will automatically change for the user.
However, judging by your post, if you're just iterating through a list of users and checking the memberOf attributes for the existence of CN=Builtin (ex. a .Contains check), then yes, you can rely on that string being there, given it's part of the DC you're querying.
I need to implement nested group membership for generic AD services.
Previously, i was using a specific search-filter ("member:1.2.840.113556.1.4.1941:=") through which using a single search request, i was able to get hold of all group membership through which that user was part of. However, it looks like that search-filter seems to work only for MS AD servers and not for generic AD servers.
So, is anybody aware of any specific search filter which we can send in a search request (applicable to All AD servers), through which i can derive nested group membership via a single search query.
Thanks in advance for your help on this.
"member:1.2.840.113556.1.4.1941" is LDAP_MATCHING_RULE_IN_CHAIN and might very well not be implemented by other LDAP vendors. LDAP Wiki
Edit:
You could do something like this if you want to reurse the groups:
Use the filter:
(&(objectCategory=organizationalPerson)(objectClass=User)(sAMAccountName=YOURUSER)
get "distinguishedName" (this is the user's distinguishedName)
get "memberOf" (this is a collection of distinguishedNames of the groups the user is a member of (minus the primary group in MS Active Directory, which should be "Domain Users"))
Foreach memberOf in the collection: (This is the first level, so there is no need to check if he is there, because he is.)
(&(objectCategory=group)(distinguishedName=THISMEMBEROF))
get "member" (this is a collection of distinguishedNames of group members)
Foreach memberOf in the collection:
This is the second level (the groups within the groups), so first check if the users distinguishedName is present.
(&(objectCategory=group)(distinguishedName=THISMEMBEROF))
get "member" (this is a collection of distinguishedNames of group members)
Foreach memberOf in the collection:
This is the third level (the groups within the groups), so first check if the users distinguishedName is present.
(&(objectCategory=group)(distinguishedName=THISMEMBEROF))
get "member" (this is a collection of distinguishedNames of group members)
etc.
An AD setup I'm using has users that are stored as members of (multiple) security groups.
I am using software that reads the memberof property of a user to work out access permissions.
In AD Explorer I can see the memberof property of the user shows the immediate security groups they belong to say 'Course - English'. It does not show the parents groups, nested up to say 'ALL Students'.
Is there a reason for this or a way of ensuring all nested groups are shown in the memberof property?
If you're on .NET 3.5 and up, you should check out the System.DirectoryServices.AccountManagement (S.DS.AM) namespace. Read all about it here:
Managing Directory Security Principals in the .NET Framework 3.5
MSDN docs on System.DirectoryServices.AccountManagement
Basically, you can define a domain context and easily find users and/or groups in AD:
// set up domain context
PrincipalContext ctx = new PrincipalContext(ContextType.Domain);
// find a user
UserPrincipal user = UserPrincipal.FindByIdentity(ctx, "SomeUserName");
if(user != null)
{
var groups = user.GetAuthorizationGroups();
// enumerate over groups
foreach(GroupPrincipal gp in groups)
{
// do something here....
}
}
The new S.DS.AM makes it really easy to play around with users and groups in AD!
The .GetAuthorizationGroups() method is the only one around that I know of that will do recursive searches, e.g. find groups that a user is member of by virtue of another group. The pre-.NET 3.5 DirectoryServices stuff doesn't do this - you would have to totally roll your own if you need that.
The probable reason that the memberOf attribute does not contain all the nested group information is that the value is computed when the attribute is loaded, as noted in this link:
Be aware that this attribute lists the groups that contain the user in their member attribute—it does not contain the recursive list of nested predecessors. For example, if user O is a member of group C and group B and group B were nested in group A, the memberOf attribute of user O would list group C and group B, but not group A.
This attribute is not stored—it is a computed back-link attribute.
Hence, to support this, your DC would be forced to load all nested groups every time a LDAP query returned the memberOf attribute, which could be a lot of excess work.
Depending on the technology you are using, there are almost certainly better ways to check group membership than loading all groups and listing them all. For example, ADSI has a pre-built function to check if a user is a member of the group.
However, for a pure LDAP solution, you could use the LDAP_MATCHING_RULE_IN_CHAIN as shown in this answer (assuming you have the DN for the user), e.g.,
(member:1.2.840.113556.1.4.1941:=CN=Administrator,OU=Users,DC=fabrikam,DC=com)
Which will get all the groups which Administrator is a member of. Note, however, that this query can be extremely slow. To speed up performance, consider paging results or restricting the search base to only the group you are interested in checking.