packet.bgp: parse/serialize FOUR OCTET AS NUMBER capability

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

2 files changed, 21 insertions, 0 deletions

diff --git a/ryu/lib/packet/bgp.py b/ryu/lib/packet/bgp.py
index 1d3d2e62..48d3f833 100644
--- a/ryu/lib/packet/bgp.py
+++ b/ryu/lib/packet/bgp.py
@@ -277,6 +277,25 @@ class BGPOptParamCapabilityRouteRefresh(_OptParamCapability):
         return bytearray()
 
 
+@_OptParamCapability.register_type(BGP_CAP_FOUR_OCTET_AS_NUMBER)
+class BGPOptParamCapabilityFourOctetAsNumber(_OptParamCapability):
+    _CAP_PACK_STR = '!I'
+
+    def __init__(self, as_number, **kwargs):
+        super(BGPOptParamCapabilityFourOctetAsNumber, self).__init__(**kwargs)
+        self.as_number = as_number
+
+    @classmethod
+    def parse_cap_value(cls, buf):
+        (as_number, ) = struct.unpack_from(cls._CAP_PACK_STR, buffer(buf))
+        return {'as_number': as_number}
+
+    def serialize_cap_value(self):
+        buf = bytearray()
+        msg_pack_into(self._CAP_PACK_STR, buf, 0, self.as_number)
+        return buf
+
+
 class BGPWithdrawnRoute(_IPAddrPrefix):
     pass
 
diff --git a/ryu/tests/unit/packet/test_bgp.py b/ryu/tests/unit/packet/test_bgp.py
index fa3b9f3c..2e1da861 100644
--- a/ryu/tests/unit/packet/test_bgp.py
+++ b/ryu/tests/unit/packet/test_bgp.py
@@ -45,6 +45,8 @@ class Test_bgp(unittest.TestCase):
         opt_param = [bgp.BGPOptParamCapabilityUnknown(cap_code=200,
                                                       cap_value='hoge'),
                      bgp.BGPOptParamCapabilityRouteRefresh(),
+                     bgp.BGPOptParamCapabilityFourOctetAsNumber(
+                         as_number=1234567),
                      bgp.BGPOptParamUnknown(type_=99, value='fuga')]
         msg = bgp.BGPOpen(my_as=30000, bgp_identifier='192.0.2.2',
                           opt_param=opt_param)