Label and allow access to /data/system/ndebugsocket.

Otherwise it defaults to the label of /data/system and
cannot be distinguished from any other socket in that directory.
Also adds allow rule required for pre-existing wpa_socket transition
to function without unconfined_domain.

Change-Id: I57179aa18786bd56d247f397347e546cca978e41
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>

debuggerd.te

@@ -7,3 +7,6 @@ init_daemon_domain(debuggerd)
 unconfined_domain(debuggerd)
 relabelto_domain(debuggerd)
 allow debuggerd tombstone_data_file:dir relabelto;
+
+# Connect to system_server via /data/system/ndebugsocket.
+unix_socket_connect(debuggerd, system_ndebug, system_server)

file.te

@@ -98,6 +98,7 @@ type racoon_socket, file_type;
 type rild_socket, file_type;
 type rild_debug_socket, file_type;
 type system_wpa_socket, file_type;
+type system_ndebug_socket, file_type;
 type vold_socket, file_type;
 type wpa_socket, file_type;
 type zygote_socket, file_type;

system_server.te

@@ -25,6 +25,12 @@ allow system_server self:capability {
 
 # Create a socket for receiving info from wpa.
 type_transition system_server wifi_data_file:sock_file system_wpa_socket;
+allow system_server system_wpa_socket:sock_file create_file_perms;
+
+# Create a socket for connections from debuggerd.
+type_transition system_server system_data_file:sock_file system_ndebug_socket "ndebugsocket";
+allow system_server system_ndebug_socket:sock_file create_file_perms;
+
 allow system_server self:zygote { specifyids specifyrlimits specifyseinfo };
 
 allow system_server backup_data_file:dir relabelto;