|
1
|
|
|
# encoding: utf-8 |
|
2
|
|
|
""" |
|
3
|
|
|
sradjlan.py |
|
4
|
|
|
|
|
5
|
|
|
Created by Evelio Vila |
|
6
|
|
|
Copyright (c) 2014-2017 Exa Networks. All rights reserved. |
|
7
|
|
|
""" |
|
8
|
|
|
|
|
9
|
|
|
import json |
|
10
|
|
|
from struct import unpack |
|
11
|
|
|
from exabgp.vendoring import six |
|
12
|
|
|
from exabgp.util import hexstring |
|
13
|
|
|
|
|
14
|
|
|
from exabgp.vendoring.bitstring import BitArray |
|
15
|
|
|
from exabgp.protocol.iso import ISO |
|
16
|
|
|
from exabgp.bgp.message.update.attribute.bgpls.linkstate import LINKSTATE, LsGenericFlags |
|
17
|
|
|
from exabgp.bgp.message.notification import Notify |
|
18
|
|
|
|
|
19
|
|
|
# 0 1 2 3 |
|
20
|
|
|
# 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
|
21
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
22
|
|
|
# | Type | Length | |
|
23
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
24
|
|
|
# | Flags | Weight | Reserved | |
|
25
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
26
|
|
|
# |
|
27
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
28
|
|
|
# | OSPF Neighbor ID / IS-IS System-ID | |
|
29
|
|
|
# + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
30
|
|
|
# | | |
|
31
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
32
|
|
|
# |
|
33
|
|
|
# +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
|
34
|
|
|
# | SID/Label/Index (variable) | |
|
35
|
|
|
# +---------------------------------------------------------------+ |
|
36
|
|
|
# draft-gredler-idr-bgp-ls-segment-routing-ext-03 |
|
37
|
|
|
|
|
38
|
|
View Code Duplication |
@LINKSTATE.register() |
|
|
|
|
|
|
39
|
|
|
class SrAdjacencyLan(object): |
|
40
|
|
|
TLV = 1100 |
|
41
|
|
|
_sr_adj_lan_sids = [] |
|
42
|
|
|
|
|
43
|
|
|
def __init__ (self): |
|
44
|
|
|
self.sr_adj_lan_sids = SrAdjacencyLan._sr_adj_lan_sids.copy() |
|
45
|
|
|
|
|
46
|
|
|
def __repr__ (self): |
|
47
|
|
|
return "sr-adj-lan-sids: {}".format(self.sr_adj_lan_sids) |
|
48
|
|
|
|
|
49
|
|
|
@classmethod |
|
50
|
|
|
def unpack (cls,data,length): |
|
51
|
|
|
# We only support IS-IS flags for now. |
|
52
|
|
|
flags = LsGenericFlags.unpack(data[0:1],LsGenericFlags.ISIS_SR_ADJ_FLAGS).flags |
|
53
|
|
|
# Parse adj weight |
|
54
|
|
|
weight = six.indexbytes(data,1) |
|
55
|
|
|
# Parse neighbor System-ID |
|
56
|
|
|
system_id = ISO.unpack_sysid(data[4:10]) |
|
57
|
|
|
# Move pointer 10 bytes: Flags(1) + Weight(1) + Reserved(2) + System-ID(6) |
|
58
|
|
|
data = data[10:] |
|
59
|
|
|
# SID/Index/Label: according to the V and L flags, it contains |
|
60
|
|
|
# either: |
|
61
|
|
|
# * A 3 octet local label where the 20 rightmost bits are used for |
|
62
|
|
|
# encoding the label value. In this case the V and L flags MUST |
|
63
|
|
|
# be set. |
|
64
|
|
|
# |
|
65
|
|
|
# * A 4 octet index defining the offset in the SID/Label space |
|
66
|
|
|
# advertised by this router using the encodings defined in |
|
67
|
|
|
# Section 3.1. In this case V and L flags MUST be unset. |
|
68
|
|
|
raw = [] |
|
69
|
|
|
while data: |
|
70
|
|
|
# Range Size: 3 octet value indicating the number of labels in |
|
71
|
|
|
# the range. |
|
72
|
|
|
if int(flags['V']) and int(flags['L']): |
|
73
|
|
|
b = BitArray(bytes=data[:3]) |
|
74
|
|
|
sid = b.unpack('uintbe:24')[0] |
|
75
|
|
|
data = data[3:] |
|
76
|
|
|
elif (not flags['V']) and (not flags['L']): |
|
77
|
|
|
sid = unpack('!I',data[:4])[0] |
|
78
|
|
|
data = data[4:] |
|
79
|
|
|
else: |
|
80
|
|
|
raw.append(hexstring(data)) |
|
81
|
|
|
break |
|
82
|
|
|
cls._sr_adj_lan_sids.append( |
|
83
|
|
|
{'flags': flags, 'weight': weight, 'system-id': system_id, 'sid': sid, 'undecoded': raw} |
|
|
|
|
|
|
84
|
|
|
) |
|
85
|
|
|
return cls() |
|
86
|
|
|
|
|
87
|
|
|
def json (self,compact=None): |
|
88
|
|
|
return '"sr-adj-lan-sids": {}'.format(json.dumps(self.sr_adj_lan_sids)) |
|
89
|
|
|
|
|
90
|
|
|
@classmethod |
|
91
|
|
|
def reset(cls): |
|
92
|
|
|
cls._sr_adj_sids = [] |
|
93
|
|
|
|
Exa-Networks /
exabgp
Loading history...
