Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/scapy/layers/hsrp.py: 84%

1# SPDX-License-Identifier: GPL-2.0-only 

2# This file is part of Scapy 

3# See https://scapy.net/ for more information 

4# Copyright (C) Mathieu RENARD <mathieu.renard(at)gmail.com> 

5 

6""" 

7HSRP (Hot Standby Router Protocol) 

8A proprietary redundancy protocol for Cisco routers. 

9 

10- HSRP Version 1: RFC 2281 

11- HSRP Version 2: 

12 http://www.smartnetworks.jp/2006/02/hsrp_8_hsrp_version_2.html 

13""" 

14 

15from scapy.config import conf 

16from scapy.fields import ByteEnumField, ByteField, IPField, SourceIPField, \ 

17 StrFixedLenField, XIntField, XShortField 

18from scapy.packet import Packet, bind_layers, bind_bottom_up 

19from scapy.layers.inet import DestIPField, UDP 

20 

21 

22class HSRP(Packet): 

23 name = "HSRP" 

24 fields_desc = [ 

25 ByteField("version", 0), 

26 ByteEnumField("opcode", 0, {0: "Hello", 1: "Coup", 2: "Resign", 3: "Advertise"}), # noqa: E501 

27 ByteEnumField("state", 16, {0: "Initial", 1: "Learn", 2: "Listen", 4: "Speak", 8: "Standby", 16: "Active"}), # noqa: E501 

28 ByteField("hellotime", 3), 

29 ByteField("holdtime", 10), 

30 ByteField("priority", 120), 

31 ByteField("group", 1), 

32 ByteField("reserved", 0), 

33 StrFixedLenField("auth", b"cisco" + b"\00" * 3, 8), 

34 IPField("virtualIP", "192.168.1.1")] 

35 

36 def guess_payload_class(self, payload): 

37 if self.underlayer.len > 28: 

38 return HSRPmd5 

39 else: 

40 return Packet.guess_payload_class(self, payload) 

41 

42 

43class HSRPmd5(Packet): 

44 name = "HSRP MD5 Authentication" 

45 fields_desc = [ 

46 ByteEnumField("type", 4, {4: "MD5 authentication"}), 

47 ByteField("len", None), 

48 ByteEnumField("algo", 0, {1: "MD5"}), 

49 ByteField("padding", 0x00), 

50 XShortField("flags", 0x00), 

51 SourceIPField("sourceip"), 

52 XIntField("keyid", 0x00), 

53 StrFixedLenField("authdigest", b"\00" * 16, 16)] 

54 

55 def post_build(self, p, pay): 

56 if self.len is None and pay: 

57 tmp_len = len(pay) 

58 p = p[:1] + hex(tmp_len)[30:] + p[30:] 

59 return p 

60 

61 

62bind_bottom_up(UDP, HSRP, dport=1985) 

63bind_bottom_up(UDP, HSRP, sport=1985) 

64bind_bottom_up(UDP, HSRP, dport=2029) 

65bind_bottom_up(UDP, HSRP, sport=2029) 

66bind_layers(UDP, HSRP, dport=1985, sport=1985) 

67bind_layers(UDP, HSRP, dport=2029, sport=2029) 

68DestIPField.bind_addr(UDP, "224.0.0.2", dport=1985) 

69if conf.ipv6_enabled: 

70 from scapy.layers.inet6 import DestIP6Field 

71 DestIP6Field.bind_addr(UDP, "ff02::66", dport=2029)