def check_fwd_dags(fwd_req, topo, lsas, solver):
correct = True
topo = topo.copy()
# Check that the topology/dag contain the destinations, otherwise add it
for dest, dag in fwd_req.iteritems():
dest_in_dag = dest in dag
dest_in_graph = dest in topo
if not dest_in_dag or not dest_in_graph:
if not dest_in_dag:
sinks = ssu.find_sink(dag)
else:
sinks = dag.predecessors(dest)
for s in sinks:
if not dest_in_dag:
dag.add_edge(s, dest)
if not dest_in_graph:
topo.add_edge(s, dest, metric=solver.new_edge_metric)
fake_nodes = {}
local_fake_nodes = collections.defaultdict(list)
f_ids = set()
for lsa in lsas:
if lsa.cost > 0:
if not lsa.node: # We added a pure fake LSA
continue
f_id = '__f_%s_%s_%s' % (lsa.node, lsa.nh, lsa.dest)
f_ids.add(f_id)
fake_nodes[(lsa.node, f_id, lsa.dest)] = lsa.nh
cost = topo[lsa.node][lsa.nh]['metric']
topo.add_edge(lsa.node, f_id, metric=cost)
topo.add_edge(f_id, lsa.dest, metric=lsa.cost - cost)
log.debug('Added a globally-visible fake node: '
'%s - %s - %s - %s - %s [-> %s]',
lsa.node, cost, f_id, lsa.cost - cost, lsa.dest, lsa.nh)
else:
local_fake_nodes[(lsa.node, lsa.dest)].append(lsa.nh)
log.debug('Added a locally-visible fake node: %s -> %s',
lsa.node, lsa.nh)
spt = ssu.all_shortest_paths(topo, metric='metric')
for dest, req_dag in fwd_req.iteritems():
log.info('Validating requirements for dest %s', dest)
dag = IGPGraph()
for n in filter(lambda n: n not in fwd_req, topo):
if n in f_ids:
continue
log.debug('Checking paths of %s', n)
for p in spt[n][0][dest]:
log.debug('Reported path: %s', p)
for u, v in zip(p[:-1], p[1:]):
try: # Are we using a globally-visible fake node?
nh = fake_nodes[(u, v, dest)]
log.debug('%s uses the globally-visible fake node %s '
'to get to %s', u, v, nh)
dag.add_edge(u, nh) # Replace by correct next-hop
break
except KeyError:
# Are we using a locally-visible one?
nh = local_fake_nodes[(u, dest)]
if nh:
log.debug('%s uses a locally-visible fake node'
' to get to %s', u, nh)
for h in nh:
dag.add_edge(u, h) # Replace by true nh
break
else:
dag.add_edge(u, v) # Otherwise follow the SP
# Now that we have the current fwing dag, compare to the requirements
for n in req_dag:
successors = set(dag.successors(n))
req_succ = set(req_dag.successors(n))
if successors ^ req_succ:
log.error('The successor sets for node %s differ, '
'REQ: %s, CURRENT: %s', n, req_succ, successors)
correct = False
predecessors = set(dag.predecessors(n))
req_pred = set(req_dag.predecessors(n))
# Also requires to have a non-null successor sets to take into
# account the fact that the destination will have new adjacencies
# through fake nodes
if predecessors ^ req_pred and successors:
log.error('The predecessors sets for %s differ, '
'REQ: %s, CURRENT: %s', n, req_pred, predecessors)
correct = False
if correct:
log.info('All forwarding requirements are enforced!')
return correct
class SouthboundListener(ShapeshifterProxy):
"""This basic controller maintains a structure describing the IGP topology
and listens for changes."""
def __init__(self, *args, **kwargs):
super(SouthboundListener, self).__init__(*args, **kwargs)
self.igp_graph = IGPGraph()
self.dirty = False
self.json_proxy = SJMPClient(hostname=CFG.get(DEFAULTSECT,
'json_hostname'),
port=CFG.getint(DEFAULTSECT, 'json_port'),
target=self)
self.quagga_manager = ProxyCloner(FakeNodeProxy, self.json_proxy)
def run(self):
"""Connect the the southbound controller. This call will not return
unless the connection is halted."""
log.info('Connecting to server ...')
self.json_proxy.communicate()
def stop(self):
"""Stop the connection to the southbound controller"""
self.json_proxy.stop()
def bootstrap_graph(self, graph, node_properties):
self.igp_graph.clear()
self.igp_graph.add_edges_from(graph)
for _, _, d in self.igp_graph.edges_iter(data=True):
sanitize_edge_data(d)
self.update_node_properties(**node_properties)
log.debug('Bootstrapped graph with edges: %s and properties: %s',
self.igp_graph.edges(data=True), node_properties)
self.received_initial_graph()
self.graph_changed()
def received_initial_graph(self):
"""Called when the initial graph has been bootstrapped, before
calling graph_changed"""
pass
def add_edge(self, source, destination, properties={'metric': 1}):
properties = sanitize_edge_data(properties)
# metric is added twice to support backward-compat.
self.igp_graph.add_edge(source, destination, properties)
log.debug('Added edge: %s-%s@%s', source, destination, properties)
# Only trigger an update if the link is bidirectional
self.dirty = self.igp_graph.has_edge(destination, source)
def commit(self):
log.debug('End of graph update')
if self.dirty:
self.dirty = False
self.graph_changed()
@abc.abstractmethod
def graph_changed(self):
"""Called when the IGP graph has changed."""
def remove_edge(self, source, destination):
# TODO: pay attention to re-add the symmetric edge if only one way
# crashed
try:
self.igp_graph.remove_edge(source, destination)
log.debug('Removed edge %s-%s', source, destination)
self.igp_graph.remove_edge(destination, source)
log.debug('Removed edge %s-%s', destination, source)
except nx.NetworkXError:
# This means that we had already removed both side of the edge
# earlier or that the adjacency was not fully established before
# going down
pass
else:
self.dirty = True
def update_node_properties(self, **properties):
log.debug('Updating node propeties: %s', properties)
for node, data in properties.iteritems():
self.igp_graph.node[node].update(data)
self.dirty = self.dirty or properties
class SouthboundListener(ShapeshifterProxy):
"""This basic controller maintains a structure describing the IGP topology
and listens for changes."""
def __init__(self, *args, **kwargs):
super(SouthboundListener, self).__init__(*args, **kwargs)
self.igp_graph = IGPGraph()
self.dirty = False
self.json_proxy = SJMPClient(hostname=CFG.get(DEFAULTSECT,
'json_hostname'),
port=CFG.getint(DEFAULTSECT, 'json_port'),
target=self)
self.quagga_manager = ProxyCloner(FakeNodeProxy, self.json_proxy)
def run(self):
"""Connect the the southbound controller. This call will not return
unless the connection is halted."""
log.info('Connecting to server ...')
self.json_proxy.communicate()
def stop(self):
"""Stop the connection to the southbound controller"""
self.json_proxy.stop()
def bootstrap_graph(self, graph, node_properties):
self.igp_graph.clear()
self.igp_graph.add_edges_from(graph)
for _, _, d in self.igp_graph.edges_iter(data=True):
sanitize_edge_data(d)
self.update_node_properties(**node_properties)
log.debug('Bootstrapped graph with edges: %s and properties: %s',
self.igp_graph.edges(data=True), node_properties)
self.received_initial_graph()
self.graph_changed()
def received_initial_graph(self):
"""Called when the initial graph has been bootstrapped, before
calling graph_changed"""
pass
def add_edge(self, source, destination, properties={'metric': 1}):
properties = sanitize_edge_data(properties)
# metric is added twice to support backward-compat.
self.igp_graph.add_edge(source, destination, properties)
log.debug('Added edge: %s-%s@%s', source, destination, properties)
# Only trigger an update if the link is bidirectional
self.dirty = self.igp_graph.has_edge(destination, source)
def commit(self):
log.debug('End of graph update')
if self.dirty:
self.dirty = False
self.graph_changed()
@abc.abstractmethod
def graph_changed(self):
"""Called when the IGP graph has changed."""
def remove_edge(self, source, destination):
# TODO: pay attention to re-add the symmetric edge if only one way
# crashed
try:
self.igp_graph.remove_edge(source, destination)
log.debug('Removed edge %s-%s', source, destination)
self.igp_graph.remove_edge(destination, source)
log.debug('Removed edge %s-%s', destination, source)
except nx.NetworkXError:
# This means that we had already removed both side of the edge
# earlier or that the adjacency was not fully established before
# going down
pass
else:
self.dirty = True
def update_node_properties(self, **properties):
log.debug('Updating node propeties: %s', properties)
for node, data in properties.iteritems():
self.igp_graph.node[node].update(data)
self.dirty = self.dirty or properties
def check_fwd_dags(fwd_req, topo, lsas, solver):
correct = True
topo = topo.copy()
# Check that the topology/dag contain the destinations, otherwise add it
for dest, dag in fwd_req.iteritems():
dest_in_dag = dest in dag
dest_in_graph = dest in topo
if not dest_in_dag or not dest_in_graph:
if not dest_in_dag:
sinks = ssu.find_sink(dag)
else:
sinks = dag.predecessors(dest)
for s in sinks:
if not dest_in_dag:
dag.add_edge(s, dest)
if not dest_in_graph:
topo.add_edge(s, dest, metric=solver.new_edge_metric)
fake_nodes = {}
local_fake_nodes = collections.defaultdict(list)
f_ids = set()
for lsa in lsas:
if lsa.cost > 0:
f_id = '__f_%s_%s_%s' % (lsa.node, lsa.nh, lsa.dest)
f_ids.add(f_id)
fake_nodes[(lsa.node, f_id, lsa.dest)] = lsa.nh
cost = topo[lsa.node][lsa.nh]['metric']
topo.add_edge(lsa.node, f_id, metric=cost)
topo.add_edge(f_id, lsa.dest, metric=lsa.cost - cost)
log.debug(
'Added a globally-visible fake node: '
'%s - %s - %s - %s - %s [-> %s]', lsa.node, cost, f_id,
lsa.cost - cost, lsa.dest, lsa.nh)
else:
local_fake_nodes[(lsa.node, lsa.dest)].append(lsa.nh)
log.debug('Added a locally-visible fake node: %s -> %s', lsa.node,
lsa.nh)
spt = ssu.all_shortest_paths(topo, metric='metric')
for dest, req_dag in fwd_req.iteritems():
log.info('Validating requirements for dest %s', dest)
dag = IGPGraph()
for n in filter(lambda n: n not in fwd_req, topo):
if n in f_ids:
continue
log.debug('Checking paths of %s', n)
for p in spt[n][0][dest]:
log.debug('Reported path: %s', p)
for u, v in zip(p[:-1], p[1:]):
try: # Are we using a globally-visible fake node?
nh = fake_nodes[(u, v, dest)]
log.debug(
'%s uses the globally-visible fake node %s '
'to get to %s', u, v, nh)
dag.add_edge(u, nh) # Replace by correct next-hop
break
except KeyError:
# Are we using a locally-visible one?
nh = local_fake_nodes[(u, dest)]
if nh:
log.debug(
'%s uses a locally-visible fake node'
' to get to %s', u, nh)
for h in nh:
dag.add_edge(u, h) # Replace by true nh
break
else:
dag.add_edge(u, v) # Otherwise follow the SP
# Now that we have the current fwing dag, compare to the requirements
for n in req_dag:
successors = set(dag.successors(n))
req_succ = set(req_dag.successors(n))
if successors ^ req_succ:
log.error(
'The successor sets for node %s differ, '
'REQ: %s, CURRENT: %s', n, req_succ, successors)
correct = False
predecessors = set(dag.predecessors(n))
req_pred = set(req_dag.predecessors(n))
# Also requires to have a non-null successor sets to take into
# account the fact that the destination will have new adjacencies
# through fake nodes
if predecessors ^ req_pred and successors:
log.error(
'The predecessors sets for %s differ, '
'REQ: %s, CURRENT: %s', n, req_pred, predecessors)
correct = False
if correct:
log.info('All forwarding requirements are enforced!')
return correct
