def build_birt(switch=None, domain=None):
"""
Build bit index routing table
:param switch: switch for which the birt should be calculated
:param domain: domain for which the birt should be build
:return: birt in format {bfr-id: [dest prefix, nbr prefix]
"""
# {bfr-id: [dest prefix, nbr prefix]
birt = {}
for destination in TopologyManager.get_topology(domain).get_nodes():
if destination != switch:
destination_device = TopologyManager.get_device(destination)
if destination_device.get_type(
) == "Host": # dont calculate entry for host
continue
try:
next_hop = TopologyManager.get_next_hop(
switch, destination, domain)
birt[destination_device.get_bfr_id(domain)] = [
destination_device.get_ip(),
next_hop.get_ip()
]
except NextHopNotFound: # maybe a path towards the destination is not yet learned
continue
return birt
def update_ipv4_entries(self, switch=None):
"""
Update ipv4 entries based on shortest path on switch
:param switch: switch where ipv4 entries will be installed
:return:
"""
paths = TopologyManager.get_paths(domain_id=0)
valid_entries = []
cur_dev = TopologyManager.get_device(switch)
for dst in [d for d in paths.get(switch, {})
if d != switch]: # don't check path from i->i
# get the next_hop towards the destination along the shortest path
dst_dev = TopologyManager.get_device(dst)
next_hop = TopologyManager.get_next_hop(start_node=switch,
destination_node=dst,
domain_id=0)
port = cur_dev.get_device_to_port(next_hop.get_name())
entry = TableEntry(
switch=switch,
match_fields={
"hdr.ipv4.dstAddr": (str(dst_dev.get_ip()), 32),
"meta.ports.status":
(BierComputation.id_to_bitstring(id=int(port)),
BierComputation.id_to_bitstring(id=int(port)))
},
action_name="ingress.ipv4_c.forward",
action_params={"port": int(port)},
priority=1)
if TableEntryManager.handle_table_entry(
manager=self.table_manager,
table_name="ingress.ipv4_c.ipv4",
table_entry=entry):
Log.async_debug("Installed IPv4 forwarding rule for", switch,
"->", dst)
valid_entries.append(entry.match_fields)
# Add decap entry
entry = TableEntry(
switch=cur_dev.get_name(),
match_fields={"hdr.ipv4.dstAddr": (str(cur_dev.get_ip()), 32)},
action_name="ingress.ipv4_c.decap",
priority=1)
if TableEntryManager.handle_table_entry(
manager=self.table_manager,
table_name="ingress.ipv4_c.ipv4",
table_entry=entry):
Log.async_debug("Installed IPv4 decap rule for", switch)
valid_entries.append(entry.match_fields)
return valid_entries
def build_bift(switch=None, domain=0):
"""
Generates the bit index forwarding table
:param switch: Switch for which the table should be calculated
:param domain: Domain for which the bift should be build
:return: bift {bfr-id: [fbm, nextHop]
"""
birt = BierComputation.build_birt(switch=switch, domain=domain)
# {bfr-id: [fbm, nextHop]
bift = {}
for dest in birt:
fbm = BierComputation.get_fbm(birt=birt,
next_hop_prefix=birt.get(dest)[1])
destination = TopologyManager.get_device_by_domain_and_id(
domain, dest)
next_hop = TopologyManager.get_next_hop(switch, destination,
domain)
bift[dest] = [fbm, next_hop.get_name()]
return bift