def unpack(cls, data, length):
# Extract node capability flags
flags = LsGenericFlags.unpack(data[0],
LsGenericFlags.ISIS_SR_CAP_FLAGS)
# Move pointer past flags and reserved bytes
data = data[2:]
sids = []
while data:
# Range Size: 3 octet value indicating the number of labels in
# the range.
b = BitArray(bytes=data[:3])
range_size = b.unpack('uintbe:24')[0]
# SID/Label: If length is set to 3, then the 20 rightmost bits
# represent a label. If length is set to 4, then the value
# represents a 32 bit SID.
t, l = unpack('!HH', data[3:7])
if t != 1161:
raise Notify(3, 5, "Invalid sub-TLV type: {}".format(t))
v = data[7:l + 7]
if l == 3:
b = BitArray(bytes=v)
sid = b.unpack('uintbe:24')[0]
elif l == 4:
sid = unpack('!I', v)[0]
sids.append((range_size, sid))
data = data[l + 7:]
return cls(sr_flags=flags.flags, sids=sids)
def unpack(cls, data, length):
# We only support IS-IS flags for now.
flags = LsGenericFlags.unpack(data[0], LsGenericFlags.ISIS_SR_FLAGS)
#
# Parse Algorithm
sr_algo = six.indexbytes(data, 1)
# Move pointer 4 bytes: Flags(1) + Algorithm(1) + Reserved(2)
data = data[4:]
# 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:
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, sr_algo=sr_algo)
def unpack(cls, data, length):
if length != 4:
raise Notify(3, 5, "Unable to decode attribute. Incorrect Size")
else:
b = BitArray(bytes=data)
colormask = b.unpack('uintbe:32')
return cls(colormask=colormask)
def unpack(cls, data, length):
protection_mask = [
'ExtraTrafic',
'Unprotected',
'Shared',
'Dedicated 1:1',
'Dedicated 1+1',
'Enhanced',
'RSV',
'RSV',
]
if length != 2:
raise Notify(3, 5, "Wrong size for protection type TLV")
else:
# We only care about the first octect
flag_array = binascii.b2a_hex(data[0])
hex_rep = hex(int(flag_array, 16))
bit_array = BitArray(hex_rep)
valid_flags = [
''.join(item) + '00'
for item in itertools.product('01', repeat=6)
]
valid_flags.append('0000')
if bit_array.bin in valid_flags:
flags = dict(zip(protection_mask, bit_array.bin))
return cls(protectionflags=flags)
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):
srgbs = []
# Flags: 16 bits of flags. None is defined by this document. The
# flag field MUST be clear on transmission and MUST be ignored at
# reception.
data = data[2:]
# SRGB: 3 octets of base followed by 3 octets of range. Note that
# the SRGB field MAY appear multiple times. If the SRGB field
# appears multiple times, the SRGB consists of multiple ranges.
while data:
b = BitArray(bytes=data[:3])
base = b.unpack('uintbe:24')[0]
b = BitArray(bytes=data[3:6])
srange = b.unpack('uintbe:24')[0]
srgbs.append((base, srange))
data = data[6:]
return cls(srgbs=srgbs)
def unpack (cls,data,length):
node_flags = ['O', 'T', 'E', 'B', 'R', 'V', 'RSV', 'RSV']
if length > 1:
raise Notify(3,5, "Node Flags TLV length too large")
else:
flag_array = binascii.b2a_hex(data[0])
hex_rep = hex(int(flag_array, 16))
bit_array = BitArray(hex_rep)
valid_flags = [''.join(item)+'00' for item in itertools.product('01', repeat=6)]
valid_flags.append('0000')
if bit_array.bin in valid_flags:
flags = dict(zip(node_flags, bit_array.bin))
return cls(nodeflags=flags)
def unpack (cls,data,length):
mpls_mask = ['LDP', 'RSVP-TE', 'RSV', 'RSV', 'RSV', 'RSV', 'RSV', 'RSV']
if length > 1:
raise Notify(3,5, "LINK TLV length too large")
else:
flag_array = binascii.b2a_hex(data[0])
hex_rep = hex(int(flag_array, 16))
bit_array = BitArray(hex_rep)
valid_flags = [''.join(item)+'000000' for item in itertools.product('01', repeat=2)]
valid_flags.append('0000')
if bit_array.bin in valid_flags:
flags = dict(zip(mpls_mask, bit_array.bin))
return cls(mplsflags=flags)
else:
raise Notify(3,5, "Invalid MPLS flags mask")
def unpack(cls,data,pattern):
pad = pattern.count('RSV')
repeat = len(pattern) - pad
flag_array = binascii.b2a_hex(data)
hex_rep = hex(int(flag_array, 16))
bit_array = BitArray(hex_rep)
valid_flags = [concat_strs(''.join(item), ''.join(itertools.repeat('0',pad)))
for item in itertools.product('01', repeat=repeat)]
valid_flags.append('0000')
if bit_array.bin in valid_flags:
flags = dict(zip(pattern, bit_array.bin))
flags = {k:int(v) for k, v in flags.items()}
else:
raise Notify(3,5, "Invalid SR flags mask")
return cls(flags=flags)
def unpack(cls, data, length):
if len(data) == 2:
# OSPF
igpmetric = unpack('!H', data)[0]
return cls(igpmetric=igpmetric)
elif len(data) == 1:
# ISIS small metrics
igpmetric = six.indexbytes(data, 0)
return cls(igpmetric=igpmetric)
elif len(data) == 3:
# ISIS wide metrics
b = BitArray(bytes=data)
igpmetric = b.unpack('uintbe:24')
return cls(igpmetric=igpmetric)
else:
raise Notify(3, 5, "Incorrect IGP Metric Size")
def unpack(cls, data, length):
igpflags = ['D', 'N', 'L', 'P']
if length > 1:
raise Notify(3, 5, "IGP Flags TLV length too large")
else:
flag_array = binascii.b2a_hex(data[0])
hex_rep = hex(int(flag_array, 16))
bit_array = BitArray(hex_rep)
valid_flags = [
''.join(item) + '0000'
for item in itertools.product('01', repeat=4)
]
valid_flags.append('0000')
if bit_array.bin in valid_flags:
flags = dict(zip(igpflags, bit_array.bin))
return cls(igpflags=flags)
else:
raise Notify(3, 5, "Invalid IGP flags mask")
def unpack(cls, data, length):
# We only support IS-IS flags for now.
flags = LsGenericFlags.unpack(data[0:1], LsGenericFlags.ISIS_SR_FLAGS)
#
# Parse Algorithm
sr_algo = six.indexbytes(data, 1)
# Move pointer 4 bytes: Flags(1) + Algorithm(1) + Reserved(2)
data = data[4:]
# 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:
if flags.flags['V'] and flags.flags['L']:
b = BitArray(bytes=data[:3])
sid = b.unpack('uintbe:24')[0]
data = data[3:]
sids.append(sid)
elif (not flags.flags['V']) and \
(not flags.flags['L']):
if len(data) != 4:
# Cisco IOS XR Software, Version 6.1.1.19I is not
# correctly setting the flags
raise Notify(
3, 5,
"SID/Label size doesn't match V and L flag state")
sid = unpack('!I', data[:4])[0]
data = data[4:]
sids.append(sid)
else:
raw.append(hexstring(data))
break
return cls(flags=flags, sids=sids, sr_algo=sr_algo, undecoded=raw)
def unpack_sysid(cls,data): b = BitArray(bytes=data) return b.hex
def unpack (cls,data,length): b = BitArray(bytes=data) return cls(areaid=b.hex)