there are any Extension of a non-profit service association to follow up solve people's problems

hi,
Is there an simple Extension that does the following:
1- create people (users “email doesn’t require”).
2- create people cases (like post layout with custom fields ).
3- none can access any case without give him the permission for the case.
4- search for the people cases

In short, the Extension of a non-profit service association to follow up solve people’s problems

What you’re looking for is basically a “forum”