Need to close the ODL Denial of Service interface

In some of my testing I've discovered an external message and code path that will cause ODL to fail. If left unfixed, I am concerned that this could be used for a Denial of Service attack

Internally, we us 'monit' to ensure all core processes are up. The following line was added last month to our monit configuration:
if failed host 127.0.0.1 with port 6653 type TCP for 3 times within 3 cycles then restart

This line causes monit to connect to ODL (via the loop-back interface) and then disconnect. After this line was added, we discovered that our ODL installations would fail after a few days of running.

I opened https://bugs.opendaylight.org/show_bug.cgi?id=2394 to track a specific problem associated with this (OFHandshake threads building up).

When an external entity opens an OpenFlow connection, but does not complete the handshake, I see log messages along the lines of:

2014-11-24 15:17:42.200 UTC [OFHandshake-7-0] WARN o.o.o.o.m.c.ErrorHandlerSimpleImpl - exception -> FIRST HELLO sending failed because of connection issue., session -> null
org.opendaylight.openflowplugin.ConnectionException: FIRST HELLO sending failed because of connection issue.
at org.opendaylight.openflowplugin.openflow.md.core.HandshakeManagerImpl.sendHelloMessage(HandshakeManagerImpl.java:297) ~[bundlefile:na]
at org.opendaylight.openflowplugin.openflow.md.core.HandshakeManagerImpl.shake(HandshakeManagerImpl.java:95) ~[bundlefile:na]
at org.opendaylight.openflowplugin.openflow.md.core.HandshakeStepWrapper.run(HandshakeStepWrapper.java:47) [bundlefile:na]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [na:1.7.0_71]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [na:1.7.0_71]
at java.lang.Thread.run(Thread.java:745) [na:1.7.0_71]

Resources are not freed and ODL eventually locks up.

I've patched by code with my patch for 2394, but I am concerned that there are other code paths that I haven't investigated.