Add Extended Next Hop Encoding Capability (Type 5)

yabgp/common/constants.py

@@ -312,10 +312,20 @@
 NEW_ROUTE_REFRESH = False
 GRACEFUL_RESTART = False
 
-# AFI_SAFI mapping
+# AFI mapping
+AFI_DICT = {
+    1: 'ipv4',
+    2: 'ipv6'
+}
+AFI_STR_DICT = {
+    'ipv4': 1,
+    'ipv6': 2
+}
 
+# AFI_SAFI mapping
 AFI_SAFI_DICT = {
     (1, 1): 'ipv4',
+    (1, 2): 'ipv4_mcast',
     (2, 1): 'ipv6',
     (1, 4): 'ipv4_lu',
     (2, 4): 'ipv6_lu',
@@ -328,8 +338,9 @@
     (2, 133): 'ipv6_flowspec'
 }
 AFI_SAFI_STR_DICT = {
-    'ipv6': (2, 1),
     'ipv4': (1, 1),
+    'ipv4_mcast': (1, 2),
+    'ipv6': (2, 1),
     'ipv4_lu': (1, 4),
     'ipv6_lu': (2, 4),
     'flowspec': (1, 133),

yabgp/config.py

@@ -20,8 +20,10 @@
 
 from oslo_config import cfg
 
-CONF = cfg.CONF
+from yabgp.common.constants import AFI_SAFI_STR_DICT
+from yabgp.common.constants import AFI_STR_DICT
 
+CONF = cfg.CONF
 
 BGP_CONFIG_OPTS = [
     cfg.IntOpt('peer_start_interval',
@@ -50,7 +52,10 @@
                 help='if support cisco multi session'),
     cfg.DictOpt('running_config',
                 default={},
-                help='The running configuration for BGP')
+                help='The running configuration for BGP'),
+    cfg.ListOpt('ext_nexthop',
+                default=[['ipv4', 'ipv6'], ['ipv4_mcast', 'ipv6'], ['vpnv4', 'ipv6']],
+                help='The ext_nexthop for BGP')
 ]
 
 CONF.register_opts(BGP_CONFIG_OPTS, group='bgp')
@@ -129,10 +134,21 @@ def get_bgp_config():
                     'enhanced_route_refresh': CONF.bgp.enhanced_route_refresh,
                     'graceful_restart': CONF.bgp.graceful_restart,
                     'cisco_multi_session': CONF.bgp.cisco_multi_session,
-                    'add_path': CONF.bgp.add_path},
+                    'add_path': CONF.bgp.add_path
+                },
                 'remote': {}
             }
         }
+        if ('vpnv4' in CONF.bgp.afi_safi) or ('vpnv6' in CONF.bgp.afi_safi):
+            ext_nexthop_from_cli = CONF.bgp.ext_nexthop
+            ext_nexthop = []
+            for each in ext_nexthop_from_cli:
+                afi_safi, nexthop_afi = each
+                ext_nexthop.append({
+                    'afi_safi': AFI_SAFI_STR_DICT[afi_safi],
+                    'nexthop_afi': AFI_STR_DICT[nexthop_afi]
+                })
+            CONF.bgp.running_config['capability']['local']['ext_nexthop'] = ext_nexthop
     else:
         LOG.error('Please provide enough parameters!')
         sys.exit()

yabgp/message/open.py

@@ -166,6 +166,7 @@ def parse(self, message):
                     # (7) enhanced route refresh
                     elif capability.capa_code == capability.ENHANCED_ROUTE_REFRESH:
                         self.capa_dict['enhanced_route_refresh'] = True
+
                     # (8) add path
                     elif capability.capa_code == capability.ADD_PATH:
                         # could be more than one add path cap for different afi safi
@@ -180,6 +181,7 @@ def parse(self, message):
                                 }
                             )
                             capability.capa_value = capability.capa_value[4:]
+
                     # (9) Long-Lived Graceful Restart (LLGR) Capability
                     elif capability.capa_code == capability.LLGR:
                         self.capa_dict['LLGR'] = []
@@ -191,6 +193,8 @@ def parse(self, message):
                                 'time': time
                             })
                             capability.capa_value = capability.capa_value[7:]
+
+                    # (10) Extended Next Hop Encoding Capability
                     elif capability.capa_code == capability.EXTENDED_NEXT_HOP:
                         self.capa_dict['ext_nexthop'] = []
                         while len(capability.capa_value) > 0:
@@ -225,9 +229,7 @@ def construct_header(msg):
         #    Maker      | Length |  Type   |  msg |
         #---------------+--------+---------+------+
         """
-        return b'\xff'*16 + struct.pack('!HB',
-                                        len(msg) + 19,
-                                        1) + msg
+        return b'\xff' * 16 + struct.pack('!HB', len(msg) + 19, 1) + msg
 
     def construct(self, my_capability):
 
@@ -252,6 +254,11 @@ def construct(self, my_capability):
         else:
             if my_capability.get('four_bytes_as'):
                 capas += Capability(capa_code=65, capa_length=4, capa_value=self.asn).construct(my_capability)
+
+        if 'ext_nexthop' in my_capability:
+            # Extended Next Hop Encoding Capability
+            capas += Capability(capa_code=5, capa_length=0).construct(my_capability)
+
         # for add path
         if my_capability.get('add_path'):
             capas += Capability(capa_code=69, capa_length=4, capa_value=my_capability['add_path']).construct()
@@ -345,7 +352,7 @@ class Capability(object):
     MULTISESSION_BGP = 0x44  # [Appanna]
     ADD_PATH = 0x45  # [draft-ietf-idr-add-paths]
     ENHANCED_ROUTE_REFRESH = 0x46
-    LLGR = 0x47   # [draft-uttaro-idr-bgp-persistence]
+    LLGR = 0x47  # [draft-uttaro-idr-bgp-persistence]
     # 70-127    Unassigned
     CISCO_ROUTE_REFRESH = 0x80  # I Can only find reference to this in the router logs
     # 128-255   Reserved for Private Use [RFC5492]
@@ -418,6 +425,22 @@ def construct(self, my_capability=None):
                 '!BBBBHBB', 2, 6, self.ADD_PATH, self.capa_length, afi_safi[0], afi_safi[1], value)
             return add_path
 
+        # (10) Extended Next Hop Encoding Capability
+        elif self.capa_code == self.EXTENDED_NEXT_HOP:
+            ext_nexthop_value = b''
+            # 1. Value
+            for each_ext_nexthop in my_capability['ext_nexthop']:
+                afi, safi = each_ext_nexthop['afi_safi']
+                nhafi = each_ext_nexthop['nexthop_afi']
+                ext_nexthop_value += struct.pack('!HHH', afi, safi, nhafi)
+
+            # 2. Header
+            ext_nexthop_value_length = len(ext_nexthop_value)
+            capability_and_ext_nexthtop_header = struct.pack('!BBBB', 2, ext_nexthop_value_length + 1 + 1,
+                                                             self.EXTENDED_NEXT_HOP, ext_nexthop_value_length)
+            ext_nexthop = capability_and_ext_nexthtop_header + ext_nexthop_value
+            return ext_nexthop
+
         elif self.capa_code == self.ENHANCED_ROUTE_REFRESH:
             return struct.pack('!BBBB', 2, 2, self.ENHANCED_ROUTE_REFRESH, 0)
 

yabgp/tests/unit/message/test_open.py

@@ -136,6 +136,70 @@ def test_parse_add_path_llgr(self):
         }
         self.assertEqual(results, self.open.parse(msg_hex[HDR_LEN:]))
 
+    def test_parse_ext_nexthop(self):
+        """
+
+        :return:
+        """
+        real_msg_hex = b'\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00S\x01' \
+                       b'\x04\xfd\xe8\x00\xb4\x01\x01\x01\x016\x02\x06\x01\x04\x00\x01\x00\x01\x02' \
+                       b'\x06\x01\x04\x00\x01\x00\x85\x02\x02\x80\x00\x02\x02\x02\x00\x02\x06A\x04' \
+                       b'\x00\x00\xfd\xe8\x02\x14\x05\x12\x00\x01\x00\x01\x00\x02\x00\x01\x00\x02' \
+                       b'\x00\x02\x00\x01\x00\x80\x00\x02'
+        open_msg = self.open.parse(real_msg_hex[HDR_LEN:])
+        results = {
+            'version': 4,
+            'asn': 65000,
+            'hold_time': 180,
+            'bgp_id': '1.1.1.1',
+            'capabilities': {
+                'afi_safi': [
+                    (1, 1),
+                    (1, 133)
+                ],
+                'cisco_route_refresh': True,
+                'route_refresh': True,
+                'four_bytes_as': True,
+                'ext_nexthop': [
+                    {'afi_safi': [1, 1], 'nexthop_afi': 2},
+                    {'afi_safi': [1, 2], 'nexthop_afi': 2},
+                    {'afi_safi': [1, 128], 'nexthop_afi': 2}
+                ]
+            }
+        }
+        self.assertEqual(results, open_msg)
+
+    def test_construct_ext_nexthop(self):
+        """
+
+        :return:
+        """
+        self.open.version = VERSION
+        self.open.asn = 65000
+        self.open.hold_time = 180
+        self.open.bgp_id = int(netaddr.IPAddress('1.1.1.1'))
+        my_capabilities = {
+            'afi_safi': [
+                (1, 1),
+                (1, 133)
+            ],
+            'cisco_route_refresh': True,
+            'route_refresh': True,
+            'four_bytes_as': True,
+            'ext_nexthop': [
+                {'afi_safi': [1, 1], 'nexthop_afi': 2},
+                {'afi_safi': [1, 2], 'nexthop_afi': 2},
+                {'afi_safi': [1, 128], 'nexthop_afi': 2}
+            ]
+        }
+        msg_hex = self.open.construct(my_capabilities)
+        hope_hex = b'\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00S\x01' \
+                   b'\x04\xfd\xe8\x00\xb4\x01\x01\x01\x016\x02\x06\x01\x04\x00\x01\x00\x01\x02' \
+                   b'\x06\x01\x04\x00\x01\x00\x85\x02\x02\x80\x00\x02\x02\x02\x00\x02\x06A\x04' \
+                   b'\x00\x00\xfd\xe8\x02\x14\x05\x12\x00\x01\x00\x01\x00\x02\x00\x01\x00\x02' \
+                   b'\x00\x02\x00\x01\x00\x80\x00\x02'
+        self.assertEqual(hope_hex, msg_hex)
+
 
 if __name__ == '__main__':
     unittest.main()