of1.2: Fix MTVlanVid() parser and serializer

- The OFPVID_PRESENT bit indicate the presence of a valid VLAN_ID.
- Reflect to unittests.

Signed-off-by: HIYAMA Manabu <hiyama.manabu@po.ntts.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

2 files changed, 32 insertions, 4 deletions

diff --git a/ryu/ofproto/ofproto_v1_2_parser.py b/ryu/ofproto/ofproto_v1_2_parser.py
index 37d1ee1d..f8d2af4b 100644
--- a/ryu/ofproto/ofproto_v1_2_parser.py
+++ b/ryu/ofproto/ofproto_v1_2_parser.py
@@ -2076,6 +2076,16 @@ class MTVlanVid(OFPMatchField):
         self.value = value
         self.mask = mask
 
+    @classmethod
+    def field_parser(cls, header, buf, offset):
+        m = super(MTVlanVid, cls).field_parser(header, buf, offset)
+        m.value &= ~ofproto_v1_2.OFPVID_PRESENT
+        return m
+
+    def serialize(self, buf, offset):
+        self.value |= ofproto_v1_2.OFPVID_PRESENT
+        super(MTVlanVid, self).serialize(buf, offset)
+
 
 @OFPMatchField.register_field_header([ofproto_v1_2.OXM_OF_VLAN_PCP])
 class MTVlanPcp(OFPMatchField):
diff --git a/ryu/tests/unit/ofproto/test_parser_v12.py b/ryu/tests/unit/ofproto/test_parser_v12.py
index 7f38725a..b1e1cfc8 100644
--- a/ryu/tests/unit/ofproto/test_parser_v12.py
+++ b/ryu/tests/unit/ofproto/test_parser_v12.py
@@ -3511,24 +3511,42 @@ class TestOFPMatch(unittest.TestCase):
 
         self._test_serialize_and_parser(header, value, match)
 
+    def _test_serialize_and_parser_vid(self, header, vid, match):
+        # match_serialize
+        buf = bytearray()
+        length = match.serialize(buf, 0)
+
+        cls_ = OFPMatchField._FIELDS_HEADERS.get(header)
+        fmt = '!HHI' + cls_.pack_str.replace('!', '')
+        res = unpack_from(fmt, buffer(buf), 0)
+
+        eq_(res[3], vid | ofproto_v1_2.OFPVID_PRESENT)
+
+        # match_parser
+        res = match.parser(str(buf), 0)
+
+        eq_(res.type, ofproto_v1_2.OFPMT_OXM)
+        eq_(res.fields[0].header, header)
+        eq_(res.fields[0].value, vid)
+
     def test_set_vlan_vid(self):
         header = ofproto_v1_2.OXM_OF_VLAN_VID
-        value = vid = 0b101010101010
+        vid = 0b101010101010
 
         match = OFPMatch()
         match.set_vlan_vid(vid)
 
-        self._test_serialize_and_parser(header, value, match)
+        self._test_serialize_and_parser_vid(header, vid, match)
 
     def test_set_vlan_vid_masked(self):
         header = ofproto_v1_2.OXM_OF_VLAN_VID_W
-        value = vid = 0b101010101010
+        vid = 0b101010101010
         mask = 0xfff
 
         match = OFPMatch()
         match.set_vlan_vid_masked(vid, mask)
 
-        self._test_serialize_and_parser(header, value, match)
+        self._test_serialize_and_parser_vid(header, vid, match)
 
     def test_set_vlan_pcp(self):
         header = ofproto_v1_2.OXM_OF_VLAN_PCP