def unpack(cls, data, igp):
dtype, dlength = unpack('!HH', data[0:4])
if dtype not in NODE_TLVS.keys():
raise Exception("Unknown Node Descriptor Sub-TLV")
# OSPF Area-ID
if dtype == 514:
return cls(node_id=IP.unpack(data[4:4 + dlength]),
dtype=dtype,
packed=data[:4 + dlength]), data[4 + dlength:]
# IGP Router-ID: The TLV size in combination with the protocol
# identifier enables the decoder to determine the type
# of the node: sec 3.2.1.4.
elif dtype == 515:
# OSPFv{2,3} non-pseudonode
if (igp == 3 or igp == 6) and dlength == 4:
r_id = IP.unpack(data[4:4 + 4])
return cls(node_id=r_id,
dtype=dtype,
packed=data[:4 + dlength]), data[4 + 4:]
# OSPFv{2,3} LAN pseudonode
if (igp == 3 or igp == 6) and dlength == 8:
r_id = IP.unpack(data[4:4 + 4])
dr_id = IP.unpack(data[8:4 + 8])
return cls(node_id=r_id,
dtype=dtype,
psn=None,
dr_id=dr_id,
packed=data[:4 + dlength]), data[4 + 8:]
# IS-IS non-pseudonode
if (igp == 1 or igp == 2) and dlength == 6:
return cls(node_id=ISO.unpack_sysid(data[4:4 + 6]),
dtype=dtype,
packed=data[:4 + dlength]), data[4 + 6:]
# IS-IS LAN pseudonode = ISO Node-ID + PSN
# Unpack ISO address
if (igp == 1 or igp == 2) and dlength == 7:
iso_node = ISO.unpack_sysid(data[4:4 + 6])
psn = unpack('!B', data[4 + 6:4 + 7])[0]
return cls(node_id=iso_node,
dtype=dtype,
psn=psn,
packed=data[:4 + dlength]), data[4 + 7:]
elif dtype == 512 and dlength == 4:
# ASN
return cls(node_id=unpack('!L', data[4:4 + dlength])[0],
dtype=dtype,
packed=data[:4 + dlength]), data[4 + 4:]
elif dtype == 513 and dlength == 4:
# BGP-LS
return cls(node_id=unpack('!L', data[4:4 + dlength])[0],
dtype=dtype,
packed=data[:4 + dlength]), data[4 + 4:]
else:
raise Notify(3, 5, 'could not decode Local Node descriptor')
def unpack(cls, data):
# We only support IS-IS flags for now.
flags = cls.unpack_flags(data[0:1])
# Parse adj weight
weight = data[1]
# Move pointer 4 bytes: Flags(1) + Weight(1) + Reserved(2)
system_id = ISO.unpack_sysid(data[4:10])
data = data[10:]
# SID/Index/Label: according to the V and L flags, it contains
# either:
# * A 3 octet local label where the 20 rightmost bits are used for
# encoding the label value. In this case the V and L flags MUST
# be set.
#
# * A 4 octet index defining the offset in the SID/Label space
# advertised by this router using the encodings defined in
# Section 3.1. In this case V and L flags MUST be unset.
sids = []
raw = []
while data:
# Range Size: 3 octet value indicating the number of labels in
# the range.
if int(flags['V']) and int(flags['L']):
sid = unpack('!L', bytes([0]) + data[:3])[0]
data = data[3:]
sids.append(sid)
elif (not flags['V']) and (not flags['L']):
sid = unpack('!I', data[:4])[0]
data = data[4:]
sids.append(sid)
else:
raw.append(hexstring(data))
break
return cls([{'flags': flags, 'weight': weight, 'system-id': system_id, 'sid': sid, 'undecoded': raw}])
def unpack(cls, data, length):
# We only support IS-IS flags for now.
flags = LsGenericFlags.unpack(data[0],
LsGenericFlags.ISIS_ADJ_SR_FLAGS)
# Parse adj weight
weight = six.indexbytes(data, 1)
# Move pointer 4 bytes: Flags(1) + Weight(1) + Reserved(2)
data = data[4:]
isis_system_id = ISO.unpack_sysid(data[:6])
# SID/Index/Label: according to the V and L flags, it contains
# either:
# * A 3 octet local label where the 20 rightmost bits are used for
# encoding the label value. In this case the V and L flags MUST
# be set.
#
# * A 4 octet index defining the offset in the SID/Label space
# advertised by this router using the encodings defined in
# Section 3.1. In this case V and L flags MUST be unset.
sids = []
while data:
# Range Size: 3 octet value indicating the number of labels in
# the range.
if flags.flags['V'] and flags.flags['L']:
b = BitArray(bytes=data[:3])
sid = b.unpack('uintbe:24')[0]
data = data[3:]
elif (not flags.flags['V']) and (not flags.flags['L']):
sid = unpack('!I', data[:4])[0]
data = data[4:]
sids.append(sid)
return cls(flags=flags.flags, sids=sids, weight=weight)
def unpack (cls,data,length):
# We only support IS-IS flags for now.
flags = LsGenericFlags.unpack(data[0:1],LsGenericFlags.ISIS_SR_ADJ_FLAGS)
# Parse adj weight
weight = six.indexbytes(data,1)
# Move pointer 4 bytes: Flags(1) + Weight(1) + Reserved(2)
data = data[4:]
isis_system_id = ISO.unpack_sysid(data[:6])
# SID/Index/Label: according to the V and L flags, it contains
# either:
# * A 3 octet local label where the 20 rightmost bits are used for
# encoding the label value. In this case the V and L flags MUST
# be set.
#
# * A 4 octet index defining the offset in the SID/Label space
# advertised by this router using the encodings defined in
# Section 3.1. In this case V and L flags MUST be unset.
sids = []
while data:
# Range Size: 3 octet value indicating the number of labels in
# the range.
if int(flags.flags['V']) and int(flags.flags['L']):
b = BitArray(bytes=data[:3])
sid = b.unpack('uintbe:24')[0]
data = data[3:]
elif (not flags.flags['V']) and \
(not flags.flags['L']):
sid = unpack('!I',data[:4])[0]
data = data[4:]
sids.append(sid)
return cls(flags=flags, sids=sids, weight=weight)
def unpack(cls, data, igp):
node_type, length = unpack('!HH', data[0:4])
packed = data[:4 + length]
payload = packed[4:]
remaining = data[4 + length:]
node_id = None
dr_id = None
psn = None
# autonomous-system
if node_type == 512:
if length != 4:
raise Exception(cls._error_tlvs[node_type])
node_id = unpack('!L', payload)[0]
return cls(node_id, node_type, psn, dr_id, packed), remaining
# bgp-ls-id
if node_type == 513:
if length != 4:
raise Exception(cls._error_tlvs[node_type])
node_id = unpack('!L', payload)[0]
return cls(node_id, node_type, psn, dr_id, packed), remaining
# ospf-area-id
if node_type == 514:
if length not in (4, 16): # FIXME: it may only need to be 4
raise Exception(cls._error_tlvs[node_type])
node_id = IP.unpack(payload)
return cls(node_id, node_type, psn, dr_id, packed), remaining
# IGP Router-ID: The TLV size in combination with the protocol
# identifier enables the decoder to determine the node_typee
# of the node: sec 3.2.1.4.
if node_type == 515:
# IS-IS non-pseudonode
if igp in (1, 2):
if length not in (6, 7):
raise Exception(cls._error_tlvs[node_type])
node_id = ISO.unpack_sysid(payload),
if length == 7:
psn = unpack('!B', payload[6:7])[0]
return cls(node_id, node_type, psn, dr_id, packed), remaining
# OSPFv{2,3} non-pseudonode
if igp in (3, 5, 6, 227):
if length not in (4, 8):
raise Exception(cls._error_tlvs[node_type])
node_id = IP.unpack(payload[:4]),
if length == 8:
dr_id = IP.unpack(payload[4:8])
return cls(node_id, node_type, psn, dr_id, packed), remaining
raise Exception("unknown node descriptor sub-tlv ({}, {})".format(
f'node-type: {node_type}',
f'igp: {igp}',
))
def unpack (cls, data, igp):
dtype, dlength = unpack('!HH',data[0:4])
if dtype not in NODE_TLVS.keys():
raise Exception("Unknown Node Descriptor Sub-TLV")
# OSPF Area-ID
if dtype == 514:
return cls(node_id=IP.unpack(data[4: 4 + dlength]),
dtype=dtype,packed=data[:4+dlength]), data[4 + dlength:]
# IGP Router-ID: The TLV size in combination with the protocol
# identifier enables the decoder to determine the type
# of the node: sec 3.2.1.4.
elif dtype == 515:
# OSPFv{2,3} non-pseudonode
if (igp == 3 or igp == 6) and dlength == 4:
r_id = IP.unpack(data[4: 4 + 4])
return cls(node_id=r_id, dtype=dtype,
packed=data[:4+dlength]), data[4 + 4:]
# OSPFv{2,3} LAN pseudonode
if (igp == 3 or igp == 6) and dlength == 8:
r_id = IP.unpack(data[4: 4 + 4])
dr_id = IP.unpack(data[8: 4 + 8])
return cls(node_id=r_id,dtype=dtype,psn=None,
dr_id=dr_id,packed=data[:4+dlength]), data[4 + 8:]
# IS-IS non-pseudonode
if (igp == 1 or igp == 2) and dlength == 6:
return cls(node_id=ISO.unpack_sysid(data[4: 4 + 6]),
dtype=dtype,packed=data[:4+dlength]), data[4 + 6:]
# IS-IS LAN pseudonode = ISO Node-ID + PSN
# Unpack ISO address
if (igp == 1 or igp == 2) and dlength == 7:
iso_node = ISO.unpack_sysid(data[4: 4 + 6])
psn = unpack('!B', data[4 + 6: 4 + 7])[0]
return cls(node_id=iso_node,dtype=dtype,
psn=psn,packed=data[:4+dlength]), data[4 + 7:]
elif dtype == 512 and dlength == 4:
# ASN
return cls(node_id=unpack('!L', data[4: 4 + dlength])[0],
dtype=dtype,packed=data[:4+dlength]), data[4 + 4:]
elif dtype == 513 and dlength == 4:
# BGP-LS
return cls(node_id=unpack('!L',data[4: 4 + dlength])[0],
dtype=dtype,packed=data[:4+dlength]), data[4 + 4:]
else:
raise Notify(3,5,'could not decode Local Node descriptor')