simple_switch_13: using table-miss flow

OVS has not yet supported table-miss flow completely, but this patch
changes simple_switch_13 to install table-miss flow entry in accordance
with OF1.3 spec.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 36 insertions, 22 deletions

diff --git a/ryu/app/simple_switch_13.py b/ryu/app/simple_switch_13.py
index 18f874c5..47cf0a7a 100644
--- a/ryu/app/simple_switch_13.py
+++ b/ryu/app/simple_switch_13.py
@@ -13,12 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import logging
-import struct
-
 from ryu.base import app_manager
 from ryu.controller import ofp_event
-from ryu.controller.handler import MAIN_DISPATCHER
+from ryu.controller.handler import CONFIG_DISPATCHER, MAIN_DISPATCHER
 from ryu.controller.handler import set_ev_cls
 from ryu.ofproto import ofproto_v1_3
 from ryu.lib.packet import packet
@@ -32,21 +29,33 @@ class SimpleSwitch13(app_manager.RyuApp):
         super(SimpleSwitch13, self).__init__(*args, **kwargs)
         self.mac_to_port = {}
 
-    def add_flow(self, datapath, port, dst, actions):
+    @set_ev_cls(ofp_event.EventOFPSwitchFeatures, CONFIG_DISPATCHER)
+    def switch_features_handler(self, ev):
+        datapath = ev.msg.datapath
+        ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
+
+        # install table-miss flow entry
+        #
+        # We specify NO BUFFER to max_len of the output action due to
+        # OVS bug. At this moment, if we specify a lesser number, e.g.,
+        # 128, OVS will send Packet-In with invalid buffer_id and
+        # truncated packet data. In that case, we cannot output packets
+        # correctly.
+        match = parser.OFPMatch()
+        actions = [parser.OFPActionOutput(ofproto.OFPP_CONTROLLER,
+                                          ofproto.OFPCML_NO_BUFFER)]
+        self.add_flow(datapath, 0, match, actions)
+
+    def add_flow(self, datapath, priority, match, actions):
         ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
 
-        match = datapath.ofproto_parser.OFPMatch(in_port=port,
-                                                 eth_dst=dst)
-        inst = [datapath.ofproto_parser.OFPInstructionActions(
-                ofproto.OFPIT_APPLY_ACTIONS, actions)]
-
-        mod = datapath.ofproto_parser.OFPFlowMod(
-            datapath=datapath, cookie=0, cookie_mask=0, table_id=0,
-            command=ofproto.OFPFC_ADD, idle_timeout=0, hard_timeout=0,
-            priority=0, buffer_id=ofproto.OFP_NO_BUFFER,
-            out_port=ofproto.OFPP_ANY,
-            out_group=ofproto.OFPG_ANY,
-            flags=0, match=match, instructions=inst)
+        inst = [parser.OFPInstructionActions(ofproto.OFPIT_APPLY_ACTIONS,
+                                             actions)]
+
+        mod = parser.OFPFlowMod(datapath=datapath, priority=priority,
+                                match=match, instructions=inst)
         datapath.send_msg(mod)
 
     @set_ev_cls(ofp_event.EventOFPPacketIn, MAIN_DISPATCHER)
@@ -54,6 +63,7 @@ class SimpleSwitch13(app_manager.RyuApp):
         msg = ev.msg
         datapath = msg.datapath
         ofproto = datapath.ofproto
+        parser = datapath.ofproto_parser
         in_port = msg.match['in_port']
 
         pkt = packet.Packet(msg.data)
@@ -75,13 +85,17 @@ class SimpleSwitch13(app_manager.RyuApp):
         else:
             out_port = ofproto.OFPP_FLOOD
 
-        actions = [datapath.ofproto_parser.OFPActionOutput(out_port)]
+        actions = [parser.OFPActionOutput(out_port)]
 
         # install a flow to avoid packet_in next time
         if out_port != ofproto.OFPP_FLOOD:
-            self.add_flow(datapath, in_port, dst, actions)
+            match = parser.OFPMatch(in_port=in_port, eth_dst=dst)
+            self.add_flow(datapath, 1, match, actions)
+
+        data = None
+        if msg.buffer_id == ofproto.OFP_NO_BUFFER:
+            data = msg.data
 
-        out = datapath.ofproto_parser.OFPPacketOut(
-            datapath=datapath, buffer_id=msg.buffer_id, in_port=in_port,
-            actions=actions)
+        out = parser.OFPPacketOut(datapath=datapath, buffer_id=msg.buffer_id,
+                                  in_port=in_port, actions=actions, data=data)
         datapath.send_msg(out)