packet.bgp: implement ROUTE REFRESH message

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

2 files changed, 61 insertions, 0 deletions

diff --git a/ryu/lib/packet/bgp.py b/ryu/lib/packet/bgp.py
index b1bc2f26..1d9b8e6a 100644
--- a/ryu/lib/packet/bgp.py
+++ b/ryu/lib/packet/bgp.py
@@ -811,6 +811,57 @@ class BGPNotification(BGPMessage):
         return msg
 
 
+@BGPMessage.register_type(BGP_MSG_ROUTE_REFRESH)
+class BGPRouteRefresh(BGPMessage):
+    """BGP-4 ROUTE REFRESH Message (RFC 2918) encoder/decoder class.
+
+    An instance has the following attributes at least.
+    Most of them are same to the on-wire counterparts but in host byte
+    order.
+    __init__ takes the correspondig args in this order.
+
+    ========================== ===============================================
+    Attribute                  Description
+    ========================== ===============================================
+    marker                     Marker field.  Ignored when encoding.
+    len                        Length field.  Ignored when encoding.
+    type                       Type field.  The default is
+                               BGP_MSG_ROUTE_REFRESH.
+    afi                        Address Family Identifier
+    safi                       Subsequent Address Family Identifier
+    ========================== ===============================================
+    """
+
+    _PACK_STR = '!HBB'
+    _MIN_LEN = BGPMessage._HDR_LEN + struct.calcsize(_PACK_STR)
+
+    def __init__(self,
+                 afi, safi, reserved=0,
+                 type_=BGP_MSG_ROUTE_REFRESH, len_=None, marker=None):
+        super(BGPRouteRefresh, self).__init__(marker=marker, len_=len_,
+                                              type_=type_)
+        self.afi = afi
+        self.safi = safi
+        self.reserved = reserved
+
+    @classmethod
+    def parser(cls, buf):
+        (afi, reserved, safi,) = struct.unpack_from(cls._PACK_STR,
+                                                    buffer(buf))
+        return {
+            "afi": afi,
+            "reserved": reserved,
+            "safi": safi,
+        }
+
+    def serialize_tail(self):
+        # fixup
+        self.reserved = 0
+
+        return bytearray(struct.pack(self._PACK_STR, self.afi,
+                                     self.reserved, self.safi))
+
+
 class StreamParser(stream_parser.StreamParser):
     """Streaming parser for BGP-4 messages.
 
diff --git a/ryu/tests/unit/packet/test_bgp.py b/ryu/tests/unit/packet/test_bgp.py
index 99db218f..889763d3 100644
--- a/ryu/tests/unit/packet/test_bgp.py
+++ b/ryu/tests/unit/packet/test_bgp.py
@@ -19,6 +19,8 @@ from nose.tools import eq_
 from nose.tools import ok_
 
 from ryu.lib.packet import bgp
+from ryu.lib.packet import afi
+from ryu.lib.packet import safi
 
 
 class Test_bgp(unittest.TestCase):
@@ -115,6 +117,14 @@ class Test_bgp(unittest.TestCase):
         eq_(len(msg), 21 + len(data))
         eq_(rest, '')
 
+    def test_route_refresh(self):
+        msg = bgp.BGPRouteRefresh(afi=afi.IP, safi=safi.MPLS_VPN)
+        binmsg = msg.serialize()
+        msg2, rest = bgp.BGPMessage.parser(binmsg)
+        eq_(str(msg), str(msg2))
+        eq_(len(msg), 23)
+        eq_(rest, '')
+
     def test_stream_parser(self):
         msgs = [
             bgp.BGPNotification(error_code=1, error_subcode=2, data="foo"),