diff options
| -rw-r--r-- | ryu/services/protocols/bgp/peer.py | 211 |
1 files changed, 45 insertions, 166 deletions
diff --git a/ryu/services/protocols/bgp/peer.py b/ryu/services/protocols/bgp/peer.py index 4bca6165..224dd8d3 100644 --- a/ryu/services/protocols/bgp/peer.py +++ b/ryu/services/protocols/bgp/peer.py @@ -588,14 +588,6 @@ class Peer(Source, Sink, NeighborConfListener, Activity): """Construct update message with Outgoing-routes path attribute appropriately cloned/copied/updated. """ - if self._neigh_conf.cap_mbgp_ipv4: - update = self._construct_bgp4_update(outgoing_route) - else: - update = self._construct_mpbgp_update(outgoing_route) - - return update - - def _construct_bgp4_update(self, outgoing_route): update = None path = outgoing_route.path # Get copy of path's path attributes. @@ -603,8 +595,14 @@ class Peer(Source, Sink, NeighborConfListener, Activity): new_pathattr = [] if path.is_withdraw: - update = BGPUpdate(withdrawn_routes=[path.nlri]) - return update + if self._neigh_conf.cap_mbgp_ipv4: + update = BGPUpdate(withdrawn_routes=[path.nlri]) + return update + else: + mpunreach_attr = BGPPathAttributeMpUnreachNLRI( + path.route_family.afi, path.route_family.safi, [path.nlri] + ) + new_pathattr.append(mpunreach_attr) else: # Supported and un-supported/unknown attributes. origin_attr = None @@ -629,6 +627,15 @@ class Peer(Source, Sink, NeighborConfListener, Activity): nexthop_attr = BGPPathAttributeNextHop(next_hop) assert nexthop_attr, 'Missing NEXTHOP mandatory attribute.' + if not self._neigh_conf.cap_mbgp_ipv4: + # We construct mpreach-nlri attribute. + mpnlri_attr = BGPPathAttributeMpReachNLRI( + path.route_family.afi, + path.route_family.safi, + next_hop, + nlri_list + ) + # ORIGIN Attribute. # According to RFC this attribute value SHOULD NOT be changed by # any other speaker. @@ -705,12 +712,27 @@ class Peer(Source, Sink, NeighborConfListener, Activity): if path_extcomm_attr: # SOO list can be configured per VRF and/or per Neighbor. # NeighborConf has this setting we add this to existing list. - soo_list = path_extcomm_attr.soo_list + communities = path_extcomm_attr.communities if self._neigh_conf.soo_list: - soo_list.extend(self._neigh_conf.soo_list) + #construct extended community + soo_list = self._neigh_conf.soo_list + subtype = 0x03 + for soo in soo_list: + first, second = soo.split(':') + if '.' in first: + c = BGPIPv4AddressSpecificExtendedCommunity( + subtype=subtype, + ipv4_address=first, + local_administrator=int(second)) + else: + c = BGPTwoOctetAsSpecificExtendedCommunity( + subtype=subtype, + as_number=int(first), + local_administrator=int(second)) + communities.append(c) + extcomm_attr = BGPPathAttributeExtendedCommunities( - path_extcomm_attr.rt_list, - soo_list + communities=communities ) # UNKOWN Attributes. @@ -720,158 +742,11 @@ class Peer(Source, Sink, NeighborConfListener, Activity): # Ordering path attributes according to type as RFC says. We set # MPReachNLRI first as advised by experts as a new trend in BGP # implementation. - new_pathattr.append(nexthop_attr) - new_pathattr.append(origin_attr) - new_pathattr.append(aspath_attr) - if multi_exit_disc: - new_pathattr.append(multi_exit_disc) - if localpref_attr: - new_pathattr.append(localpref_attr) - if community_attr: - new_pathattr.append(community_attr) - if extcomm_attr: - new_pathattr.append(extcomm_attr) - if unkown_opttrans_attrs: - new_pathattr.extend(unkown_opttrans_attrs.values()) - - update = BGPUpdate(path_attributes=new_pathattr, - nlri=nlri_list) - return update - - def _construct_mpbgp_update(self, outgoing_route): - """Construct update message with Outgoing-routes path attribute - appropriately cloned/copied/updated. - """ - # TODO(PH): Investigate how this case needs to be handled for iBGP. - update = None - path = outgoing_route.path - # Get copy of path's path attributes. - pathattr_map = path.pathattr_map - new_pathattr = [] - - # If this is withdraw update we copy MpUnReach path-attribute and - # create new Update message. - if path.is_withdraw: - # MP_UNREACH_NLRI Attribute. - mpunreach_attr = BGPPathAttributeMpUnreachNLRI( - path.route_family.afi, path.route_family.safi, [path.nlri] - ) - new_pathattr.append(mpunreach_attr) - else: - # Supported and un-supported/unknown attributes. - origin_attr = None - aspath_attr = None - mpnlri_attr = None - extcomm_attr = None - community_attr = None - localpref_attr = None - unkown_opttrans_attrs = None - - # MP_REACH_NLRI Attribute. - # By default we use BGPS's interface IP with this peer as next_hop. - # TODO(PH): change to use protocol's local address. - # next_hop = self._neigh_conf.host_bind_ip - next_hop = self._session_next_hop(path.route_family) - # If this is a iBGP peer. - if not self.is_ebgp_peer() and path.source is not None: - # If the path came from a bgp peer and not from NC, according - # to RFC 4271 we should not modify next_hop. - next_hop = path.nexthop - # We construct mpreach-nlri attribute. - mpnlri_attr = BGPPathAttributeMpReachNLRI( - path.route_family.afi, - path.route_family.safi, - next_hop, - [path.nlri] - ) - - # ORIGIN Attribute. - # According to RFC this attribute value SHOULD NOT be changed by - # any other speaker. - origin_attr = pathattr_map.get(BGP_ATTR_TYPE_ORIGIN) - assert origin_attr, 'Missing ORIGIN mandatory attribute.' - - # AS_PATH Attribute. - # Construct AS-path-attr using paths aspath attr. with local AS as - # first item. - path_aspath = pathattr_map.get(BGP_ATTR_TYPE_AS_PATH) - assert path_aspath, 'Missing AS_PATH mandatory attribute.' - # Deep copy aspath_attr value - path_seg_list = path_aspath.path_seg_list - # If this is a iBGP peer. - if not self.is_ebgp_peer(): - # When a given BGP speaker advertises the route to an internal - # peer, the advertising speaker SHALL NOT modify the AS_PATH - # attribute associated with the route. - aspath_attr = BGPPathAttributeAsPath(path_seg_list) + if self._neigh_conf.cap_mbgp_ipv4: + new_pathattr.append(nexthop_attr) else: - # When a given BGP speaker advertises the route to an external - # peer, the advertising speaker updates the AS_PATH attribute - # as follows: - # 1) if the first path segment of the AS_PATH is of type - # AS_SEQUENCE, the local system prepends its own AS num as - # the last element of the sequence (put it in the left-most - # position with respect to the position of octets in the - # protocol message). If the act of prepending will cause an - # overflow in the AS_PATH segment (i.e., more than 255 - # ASes), it SHOULD prepend a new segment of type AS_SEQUENCE - # and prepend its own AS number to this new segment. - # - # 2) if the first path segment of the AS_PATH is of type AS_SET - # , the local system prepends a new path segment of type - # AS_SEQUENCE to the AS_PATH, including its own AS number in - # that segment. - # - # 3) if the AS_PATH is empty, the local system creates a path - # segment of type AS_SEQUENCE, places its own AS into that - # segment, and places that segment into the AS_PATH. - if (len(path_seg_list) > 0 and - isinstance(path_seg_list[0], list) and - len(path_seg_list[0]) < 255): - path_seg_list[0].insert(0, self._core_service.asn) - else: - path_seg_list.insert(0, [self._core_service.asn]) - aspath_attr = BGPPathAttributeAsPath(path_seg_list) - - # MULTI_EXIT_DISC Attribute. - # For eBGP session we can send multi-exit-disc if configured. - multi_exit_disc = None - if self.is_ebgp_peer(): - multi_exit_disc = pathattr_map.get( - BGP_ATTR_TYPE_MULTI_EXIT_DISC) - - # LOCAL_PREF Attribute. - if not self.is_ebgp_peer(): - # For iBGP peers we are required to send local-pref attribute - # for connected or local prefixes. We send default local-pref. - localpref_attr = pathattr.LocalPref(100) + new_pathattr.append(mpnlri_attr) - # COMMUNITY Attribute. - community_attr = pathattr_map.get(BGP_ATTR_TYPE_COMMUNITIES) - - # EXTENDED COMMUNITY Attribute. - # Construct ExtCommunity path-attr based on given. - path_extcomm_attr = pathattr_map.get( - BGP_ATTR_TYPE_EXTENDED_COMMUNITIES - ) - if path_extcomm_attr: - # SOO list can be configured per VRF and/or per Neighbor. - # NeighborConf has this setting we add this to existing list. - soo_list = path_extcomm_attr.soo_list - if self._neigh_conf.soo_list: - soo_list.extend(self._neigh_conf.soo_list) - extcomm_attr = BGPPathAttributeExtendedCommunities( - path_extcomm_attr.rt_list+soo_list - ) - - # UNKOWN Attributes. - # Get optional transitive path attributes - unkown_opttrans_attrs = bgp_utils.get_unknow_opttrans_attr(path) - - # Ordering path attributes according to type as RFC says. We set - # MPReachNLRI first as advised by experts as a new trend in BGP - # implementation. - new_pathattr.append(mpnlri_attr) new_pathattr.append(origin_attr) new_pathattr.append(aspath_attr) if multi_exit_disc: @@ -885,8 +760,12 @@ class Peer(Source, Sink, NeighborConfListener, Activity): if unkown_opttrans_attrs: new_pathattr.extend(unkown_opttrans_attrs.values()) - update = BGPUpdate(path_attributes=new_pathattr) - return update + if self._neigh_conf.cap_mbgp_ipv4: + update = BGPUpdate(path_attributes=new_pathattr, + nlri=nlri_list) + else: + update = BGPUpdate(path_attributes=new_pathattr) + return update def _connect_loop(self, client_factory): """In the current greeenlet we try to establish connection with peer. |