get all Active Directory groups a user is member in

Question

I am looking for a simple way to get all Active Directory Groups a given User is member in. There are two methods in UserPrincipal, but both don't match this requirement:

• GetGroups(): returns all groups, but not recursive:

  This method returns only the groups of which the principal is directly a member; no recursive searches are performed.

• GetAuthorizationGroups(): works recursive, but returns only security groups (no distribution groups)

  This function only returns groups that are security groups; distribution groups are not returned.

Unfortunately, I am not able to find something like GetAllGroups() or GetDistributionGroups(). Is there a short solution to get security and distribution groups recursively?

Answer 1

I ended up writing the method myself, it is suprisingly short.
Most helpful is that Principal itself contains the .GetGroups()-Method and therefore it is easy to write a recursive Method that returns all Groups of the given User- oder GroupPrincipal.

The code:

private static HashSet<GroupPrincipal> GetAllGroups(Principal principal)
{
    Dictionary<string, GroupPrincipal> groups = new Dictionary<string, GroupPrincipal>();
    foreach (GroupPrincipal group in principal.GetGroups())
    {
        groups[group.Sid.ToString()] = group;
        foreach (GroupPrincipal childGroup in GetAllGroups(group))
        {
            groups[childGroup.Sid.ToString()] = childGroup;
        }
    }
    return new HashSet<GroupPrincipal>(groups.Values);
}