We access our Subversion repositories mainly via svn+ssh:// on a central server. We limit access to the repos using Unix group membership. For example, the repo for ProjectA has 770 permissions and belongs to GroupA and ProjectB also has 770 permission and belongs to GroupB. So users who are in GroupA can access ProjectA and users in GroupB can access ProjectB. The file permissions look like this:
drwxrws--- 7 svn GroupA 4096 Dec 27 2009 ProjectA
drwxrws--- 7 svn GroupB 4096 Dec 27 2009 ProjectB
Everything is working as expected so far. Users in each group can only access their respective projects, and users in both groups can access both projects. But now we want to prevent a subset of users in GroupB from accessing certain subtrees of ProjectB. Can this be done when using svn+ssh:// access? If so, how?