ONOS-1993 Implement API-level permission checking + security util code location replacement

Change-Id: I7bf20eda9c12ed2a44334504333b093057764cd2
diff --git a/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java b/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java
index 749a722..0852447 100644
--- a/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java
+++ b/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java
@@ -24,6 +24,7 @@
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
+import org.onosproject.core.Permission;
 import org.onosproject.net.ConnectPoint;
 import org.onosproject.net.DefaultEdgeLink;
 import org.onosproject.net.DefaultPath;
@@ -49,6 +50,8 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static org.slf4j.LoggerFactory.getLogger;
+import static org.onosproject.security.AppGuard.checkPermission;
+
 
 /**
  * Provides implementation of a path selection service atop the current
@@ -85,11 +88,15 @@
 
     @Override
     public Set<Path> getPaths(ElementId src, ElementId dst) {
+        checkPermission(Permission.TOPOLOGY_READ);
+
         return getPaths(src, dst, null);
     }
 
     @Override
     public Set<Path> getPaths(ElementId src, ElementId dst, LinkWeight weight) {
+        checkPermission(Permission.TOPOLOGY_READ);
+
         checkNotNull(src, ELEMENT_ID_NULL);
         checkNotNull(dst, ELEMENT_ID_NULL);