Merge pull request #23 from xiaopeng163/master

add attributes and init nlri

tox.ini

@@ -39,7 +39,8 @@ commands = python -m testtools.run \
     yabgp.tests.unit.message.attribute.test_community \
     yabgp.tests.unit.message.attribute.test_originatorid \
     yabgp.tests.unit.message.attribute.test_clusterlist \
-    yabgp.tests.unit.message.attribute.test_extcommunity
+    yabgp.tests.unit.message.attribute.test_extcommunity \
+    yabgp.tests.unit.message.attribute.nlri.test_ipv4_mpls_vpn
 
 [testenv:docs]
 deps=

yabgp/common/constants.py

@@ -115,6 +115,11 @@
 # Unkonw
 BGP_EXT_COM_UNKNOW = 0x0000
 
+# route distinguisher type
+BGP_ROUTE_DISTINGUISHER_TYPE_0 = 0x0000
+BGP_ROUTE_DISTINGUISHER_TYPE_1 = 0x0001
+BGP_ROUTE_DISTINGUISHER_TYPE_2 = 0x0001
+
 # NLRI type as define in BGP flow spec RFC
 BGPNLRI_FSPEC_DST_PFIX = 1  # RFC 5575
 BGPNLRI_FSPEC_SRC_PFIX = 2  # RFC 5575

yabgp/message/attribute/mpreachnlri.py

@@ -0,0 +1,80 @@
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""BGP Attribute MP_REACH_NLRI
+"""
+
+import struct
+
+from yabgp.message.attribute import Attribute
+from yabgp.message.attribute import AttributeFlag
+from yabgp.message.attribute import AttributeID
+from yabgp.common import afn
+from yabgp.common import safn
+from yabgp.common import exception as excep
+from yabgp.common import constants as bgp_cons
+from yabgp.message.attribute.nlri.ipv4_mpls_vpn import IPv4MPLSVPN
+
+
+class MpReachNLRI(Attribute):
+    """
+        MP_REACH_NLRI (type code 14) is used to carry the set of reachable
+    destinations together with the next hop information to be used for
+    forwarding to these destinations (RFC 4760 page 2).
+
+        MP_REACH_NLRI coding information
+        +---------------------------------------------------------+
+        | Address Family Identifier (2 octets)                    |
+        +---------------------------------------------------------+
+        | Subsequent Address Family Identifier (1 octet)          |
+        +---------------------------------------------------------+
+        | Length of Next Hop Network Address (1 octet)            |
+        +---------------------------------------------------------+
+        | Network Address of Next Hop (variable)                  |
+        +---------------------------------------------------------+
+        | Reserved (1 octet)                                      |
+        +---------------------------------------------------------+
+        | Network Layer Reachability Information (variable)       |
+        +---------------------------------------------------------+
+    """
+
+    ID = AttributeID.MP_REACH_NLRI
+    FLAG = AttributeFlag.OPTIONAL
+
+    @classmethod
+    def parse(cls, value):
+
+        try:
+            afi, safi, nexthop_length = struct.unpack('!HBB', value[0:4])
+            nexthop_data = value[4:4 + nexthop_length]
+            nlri_data = value[5 + nexthop_length:]
+        except Exception:
+            # error when lenght is wrong
+            raise excep.UpdateMessageError(
+                sub_error=bgp_cons.ERR_MSG_UPDATE_ATTR_LEN,
+                data=repr(value))
+        if afi == afn.AFNUM_INET:
+            if safi == safn.SAFNUM_LAB_VPNUNICAST:
+                nlri = IPv4MPLSVPN.parse(nlri_data)
+
+        return {
+            'afi_safi': (afi, safi),
+            'nexthop': nexthop_data,
+            'nlri': nlri
+        }
+
+    @classmethod
+    def construct(cls, value):
+        pass

yabgp/message/attribute/mpunreachnlri.py

@@ -0,0 +1,51 @@
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""BGP Attribute MP_UNREACH_NLRI
+"""
+
+from yabgp.message.attribute import Attribute
+from yabgp.message.attribute import AttributeFlag
+from yabgp.message.attribute import AttributeID
+
+
+class MpUnReachNLRI(Attribute):
+
+    """
+        This is an optional non-transitive attribute that can be used for the
+    purpose of withdrawing multiple unfeasible routes from service.
+        An UPDATE message that contains the MP_UNREACH_NLRI is not required
+    to carry any other path attributes.
+
+        MP_UNREACH_NLRI coding information
+        +---------------------------------------------------------+
+        | Address Family Identifier (2 octets)                    |
+        +---------------------------------------------------------+
+        | Subsequent Address Family Identifier (1 octet)          |
+        +---------------------------------------------------------+
+        | Withdrawn Routes (variable)                             |
+        +---------------------------------------------------------+
+    """
+
+    ID = AttributeID.MP_UNREACH_NLRI
+    FLAG = AttributeFlag.OPTIONAL
+
+    @classmethod
+    def parse(cls, value):
+        pass
+
+    @classmethod
+    def construct(cls, value):
+        pass

yabgp/message/attribute/nlri/ipv4_flow_spec.py

@@ -0,0 +1,33 @@
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""IPv4 Flowspec NLRI
+"""
+
+
+class IPv4FlowSpec(object):
+
+    @classmethod
+    def parse(cls, value):
+        """
+        parse IPv4 flowspec NLRI
+        :param value:
+        :return:
+        """
+        pass
+
+    @classmethod
+    def construct(cls, value):
+        pass

yabgp/message/attribute/nlri/ipv4_mpls_vpn.py

@@ -0,0 +1,107 @@
+# coding=utf-8
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""IPv4 MPLS VPN NLRI
+"""
+
+import struct
+import logging
+import binascii
+
+import netaddr
+
+from yabgp.common import constants as bgp_cons
+
+LOG = logging.getLogger(__name__)
+
+
+class IPv4MPLSVPN(object):
+
+    """
+    IPv4 MPLS VPN NLRI
+
+    +---------------------------+
+    | Length (1 octet)          |
+    +---------------------------+
+    | Label  (3 octet)          |
+    +---------------------------+
+    |...........................|
+    +---------------------------+
+    | Prefix (variable)         |
+    +---------------------------+
+    a) Length: The Length field indicates the length, in bits, of the address prefix.
+    b) Label: (24 bits) Carries one or more labels in a stack, although a BGP update
+    has only one label. This field carries the following parts of the MPLS shim header:
+        Label Value–—20 Bits
+        Experimental bits—3 Bits
+        Bottom of stack bit—1 bit
+    c) Prefix: different coding way according to different SAFI
+    Route Distinguisher (8 bytes) plus IPv4  prefix (32 bits) or IPv6 prefix(128 bits)
+    rd (Route Distinguisher) structure (RFC 4364)
+    """
+
+    @classmethod
+    def parse(cls, value):
+        """
+        parse nlri
+        :param value: the raw hex nlri value
+        :return: nlri list
+        """
+        nlri_list = []
+        while value:
+            nlri_dict = {}
+            # for python2 and python3
+            if isinstance(value[0], int):
+                prefix_bit_len = value[0]
+            else:
+                prefix_bit_len = ord(value[0])
+            if prefix_bit_len % 8 == 0:
+                prefix_byte_len = int(prefix_bit_len / 8)
+            else:
+                prefix_byte_len = int(prefix_bit_len / 8) + 1
+
+            label_int = int(binascii.b2a_hex(value[1:4]), 16)
+            nlri_dict['label'] = (label_int >> 4, label_int & 1)
+
+            rd = value[4:12]
+            rd_type = struct.unpack('!H', rd[0:2])[0]
+            rd_value = rd[2:8]
+            nlri_dict['rd_type'] = rd_type
+            if rd_type == bgp_cons.BGP_ROUTE_DISTINGUISHER_TYPE_0:
+                asn, an = struct.unpack('!HI', rd_value)
+                nlri_dict['rd'] = '%s:%s' % (asn, an)
+            elif rd_type == bgp_cons.BGP_ROUTE_DISTINGUISHER_TYPE_1:
+                ip = str(netaddr.IPAddress(struct.unpack('!I', rd_value[0:4])[0]))
+                an = struct.unpack('!H', rd_value[4:6])[0]
+                nlri_dict['rd'] = '%s:%s' % (ip, an)
+            elif rd_type == bgp_cons.BGP_ROUTE_DISTINGUISHER_TYPE_2:
+                asn, an = struct.unpack('!IH', rd_value)
+                nlri_dict['rd'] = '%s:%s' % (asn, an)
+            else:
+                LOG.warning('unknow rd type for nlri, type=%s' % rd_type)
+                nlri_dict['rd'] = '%s:%s' % (0, 0)
+            prefix = value[12:prefix_byte_len + 1]
+            if len(prefix) < 4:
+                prefix += '\x00' * (4 - len(prefix))
+            nlri_dict['str'] = str(netaddr.IPAddress(struct.unpack('!I', prefix)[0])) +\
+                '/%s' % (prefix_bit_len - 88)
+            value = value[prefix_byte_len + 1:]
+            nlri_list.append(nlri_dict)
+        return nlri_list
+
+    @classmethod
+    def contruct(cls, value):
+        pass

yabgp/message/attribute/nlri/ipv6_mpls_vpn.py

@@ -0,0 +1,17 @@
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""IPv6 MPLS VPN NLRI
+"""

yabgp/tests/unit/message/attribute/nlri/test_ipv4_mpls_vpn.py

@@ -0,0 +1,31 @@
+# Copyright 2015 Cisco Systems, Inc.
+# All rights reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+""" Test IPv4 MPLS VPN NLRI """
+
+import unittest
+
+from yabgp.message.attribute.nlri.ipv4_mpls_vpn import IPv4MPLSVPN
+
+
+class TestIPv4MPLSVPN(unittest.TestCase):
+
+    def test_parse(self):
+        nlri_hex = b'\x78\x00\x01\x91\x00\x00\x00\x64\x00\x00\x00\x64\xaa\x00\x00\x00'
+        self.assertEqual(
+            [{'label': (25, 1), 'rd': '100:100', 'rd_type': 0, 'str': '170.0.0.0/32'}], IPv4MPLSVPN.parse(nlri_hex))
+
+if __name__ == '__main__':
+    unittest.main()