Initial set of Fabric switch test cases

Change-Id: I86fd2b67d3b773aa496f5ef61f1e1fdf51fd9925
diff --git a/Fabric/Utilities/src/python/oftest/illegal_message.py b/Fabric/Utilities/src/python/oftest/illegal_message.py
new file mode 100644
index 0000000..94c9572
--- /dev/null
+++ b/Fabric/Utilities/src/python/oftest/illegal_message.py
@@ -0,0 +1,59 @@
+
+# Copyright 2017-present Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+"""
+Support an illegal message
+"""
+
+import struct
+import ofp
+
+class illegal_message_type(object):
+    version = ofp.OFP_VERSION
+    type = 217
+
+    def __init__(self, xid=None):
+        self.xid = xid
+
+    def pack(self):
+        packed = []
+        packed.append(struct.pack("!B", self.version))
+        packed.append(struct.pack("!B", self.type))
+        packed.append(struct.pack("!H", 0)) # placeholder for length at index 2
+        packed.append(struct.pack("!L", self.xid))
+        length = sum([len(x) for x in packed])
+        packed[2] = struct.pack("!H", length)
+        return ''.join(packed)
+
+    @staticmethod
+    def unpack(buf):
+        raise NotImplementedError()
+
+    def __eq__(self, other):
+        if type(self) != type(other): return False
+        if self.version != other.version: return False
+        if self.type != other.type: return False
+        if self.xid != other.xid: return False
+        return True
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+    def __str__(self):
+        return self.show()
+
+    def show(self):
+        return "illegal_message_type"