1 """ BFD protocol implementation """
3 from random import randint
4 from socket import AF_INET, AF_INET6, inet_pton
5 from scapy.all import bind_layers
6 from scapy.layers.inet import UDP
7 from scapy.packet import Packet
8 from scapy.fields import BitField, BitEnumField, XByteField, FlagsField,\
9 ConditionalField, StrField
10 from vpp_object import VppObject
11 from util import NumericConstant
14 class BFDDiagCode(NumericConstant):
15 """ BFD Diagnostic Code """
17 control_detection_time_expired = 1
18 echo_function_failed = 2
19 neighbor_signaled_session_down = 3
20 forwarding_plane_reset = 4
22 concatenated_path_down = 6
23 administratively_down = 7
24 reverse_concatenated_path_down = 8
27 no_diagnostic: "No diagnostic",
28 control_detection_time_expired: "Control Detection Time Expired",
29 echo_function_failed: "Echo Function Failed",
30 neighbor_signaled_session_down: "Neighbor Signaled Session Down",
31 forwarding_plane_reset: "Forwarding Plane Reset",
32 path_down: "Path Down",
33 concatenated_path_down: "Concatenated Path Down",
34 administratively_down: "Administratively Down",
35 reverse_concatenated_path_down: "Reverse Concatenated Path Down",
38 def __init__(self, value):
39 NumericConstant.__init__(self, value)
42 class BFDState(NumericConstant):
50 admin_down: "AdminDown",
56 def __init__(self, value):
57 NumericConstant.__init__(self, value)
60 class BFDAuthType(NumericConstant):
61 """ BFD Authentication Type """
65 meticulous_keyed_md5 = 3
67 meticulous_keyed_sha1 = 5
70 no_auth: "No authentication",
71 simple_pwd: "Simple Password",
72 keyed_md5: "Keyed MD5",
73 meticulous_keyed_md5: "Meticulous Keyed MD5",
74 keyed_sha1: "Keyed SHA1",
75 meticulous_keyed_sha1: "Meticulous Keyed SHA1",
78 def __init__(self, value):
79 NumericConstant.__init__(self, value)
82 def bfd_is_auth_used(pkt):
83 """ is packet authenticated? """
84 return "A" in pkt.sprintf("%BFD.flags%")
87 def bfd_is_simple_pwd_used(pkt):
88 """ is simple password authentication used? """
89 return bfd_is_auth_used(pkt) and pkt.auth_type == BFDAuthType.simple_pwd
92 def bfd_is_sha1_used(pkt):
93 """ is sha1 authentication used? """
94 return bfd_is_auth_used(pkt) and pkt.auth_type in \
95 (BFDAuthType.keyed_sha1, BFDAuthType.meticulous_keyed_sha1)
98 def bfd_is_md5_used(pkt):
99 """ is md5 authentication used? """
100 return bfd_is_auth_used(pkt) and pkt.auth_type in \
101 (BFDAuthType.keyed_md5, BFDAuthType.meticulous_keyed_md5)
104 def bfd_is_md5_or_sha1_used(pkt):
105 """ is md5 or sha1 used? """
106 return bfd_is_md5_used(pkt) or bfd_is_sha1_used(pkt)
110 """ BFD protocol layer for scapy """
112 udp_dport = 3784 #: BFD destination port per RFC 5881
113 udp_sport_min = 49152 #: BFD source port min value per RFC 5881
114 udp_sport_max = 65535 #: BFD source port max value per RFC 5881
115 bfd_pkt_len = 24 # : length of BFD pkt without authentication section
116 sha1_auth_len = 28 # : length of authentication section if SHA1 used
121 BitField("version", 1, 3),
122 BitEnumField("diag", 0, 5, BFDDiagCode.desc_dict),
123 BitEnumField("state", 0, 2, BFDState.desc_dict),
124 FlagsField("flags", 0, 6, ['M', 'D', 'A', 'C', 'F', 'P']),
125 XByteField("detect_mult", 0),
126 BitField("length", bfd_pkt_len, 8),
127 BitField("my_discriminator", 0, 32),
128 BitField("your_discriminator", 0, 32),
129 BitField("desired_min_tx_interval", 0, 32),
130 BitField("required_min_rx_interval", 0, 32),
131 BitField("required_min_echo_rx_interval", 0, 32),
133 BitEnumField("auth_type", 0, 8, BFDAuthType.desc_dict),
135 ConditionalField(BitField("auth_len", 0, 8), bfd_is_auth_used),
136 ConditionalField(BitField("auth_key_id", 0, 8), bfd_is_auth_used),
137 ConditionalField(BitField("auth_reserved", 0, 8),
138 bfd_is_md5_or_sha1_used),
140 BitField("auth_seq_num", 0, 32), bfd_is_md5_or_sha1_used),
141 ConditionalField(StrField("auth_key_hash", "0" * 16), bfd_is_md5_used),
143 StrField("auth_key_hash", "0" * 20), bfd_is_sha1_used),
147 return self.sprintf("BFD(my_disc=%BFD.my_discriminator%,"
148 "your_disc=%BFD.your_discriminator%)")
150 # glue the BFD packet class to scapy parser
151 bind_layers(UDP, BFD, dport=BFD.udp_dport)
154 class VppBFDAuthKey(VppObject):
155 """ Represents BFD authentication key in VPP """
157 def __init__(self, test, conf_key_id, auth_type, key):
160 self._auth_type = auth_type
161 test.assertIn(auth_type, BFDAuthType.desc_dict)
162 self._conf_key_id = conf_key_id
166 """ Test which created this key """
171 """ Authentication type for this key """
172 return self._auth_type
180 def conf_key_id(self):
181 """ configuration key ID """
182 return self._conf_key_id
184 def add_vpp_config(self):
185 self.test.vapi.bfd_auth_set_key(
186 self._conf_key_id, self._auth_type, self._key)
187 self._test.registry.register(self, self.test.logger)
189 def get_bfd_auth_keys_dump_entry(self):
190 """ get the entry in the auth keys dump corresponding to this key """
191 result = self.test.vapi.bfd_auth_keys_dump()
193 if k.conf_key_id == self._conf_key_id:
197 def query_vpp_config(self):
198 return self.get_bfd_auth_keys_dump_entry() is not None
200 def remove_vpp_config(self):
201 self.test.vapi.bfd_auth_del_key(self._conf_key_id)
204 return "bfd-auth-key-%s" % self._conf_key_id
207 return self.object_id()
210 class VppBFDUDPSession(VppObject):
211 """ Represents BFD UDP session in VPP """
213 def __init__(self, test, interface, peer_addr, local_addr=None, af=AF_INET,
214 desired_min_tx=100000, required_min_rx=100000, detect_mult=3,
215 sha1_key=None, bfd_key_id=None):
217 self._interface = interface
219 self._local_addr = local_addr
220 if local_addr is not None:
221 self._local_addr_n = inet_pton(af, local_addr)
223 self._local_addr_n = None
224 self._peer_addr = peer_addr
225 self._peer_addr_n = inet_pton(af, peer_addr)
226 self._desired_min_tx = desired_min_tx
227 self._required_min_rx = required_min_rx
228 self._detect_mult = detect_mult
229 self._sha1_key = sha1_key
230 self._bfd_key_id = bfd_key_id if bfd_key_id else randint(0, 255)
234 """ Test which created this session """
239 """ Interface on which this session lives """
240 return self._interface
244 """ Address family - AF_INET or AF_INET6 """
248 def local_addr(self):
249 """ BFD session local address (VPP address) """
250 if self._local_addr is None:
251 if self.af == AF_INET:
252 return self._interface.local_ip4
253 elif self.af == AF_INET6:
254 return self._interface.local_ip6
256 raise Exception("Unexpected af '%s'" % self.af)
257 return self._local_addr
260 def local_addr_n(self):
261 """ BFD session local address (VPP address) - raw, suitable for API """
262 if self._local_addr is None:
263 if self.af == AF_INET:
264 return self._interface.local_ip4n
265 elif self.af == AF_INET6:
266 return self._interface.local_ip6n
268 raise Exception("Unexpected af '%s'" % self.af)
269 return self._local_addr_n
273 """ BFD session peer address """
274 return self._peer_addr
277 def peer_addr_n(self):
278 """ BFD session peer address - raw, suitable for API """
279 return self._peer_addr_n
281 def get_bfd_udp_session_dump_entry(self):
282 """ get the namedtuple entry from bfd udp session dump """
283 result = self.test.vapi.bfd_udp_session_dump()
285 self.test.logger.debug("session entry: %s" % str(s))
286 if s.sw_if_index == self.interface.sw_if_index:
287 if self.af == AF_INET \
289 and self.interface.local_ip4n == s.local_addr[:4] \
290 and self.interface.remote_ip4n == s.peer_addr[:4]:
292 if self.af == AF_INET6 \
294 and self.interface.local_ip6n == s.local_addr \
295 and self.interface.remote_ip6n == s.peer_addr:
301 """ BFD session state """
302 session = self.get_bfd_udp_session_dump_entry()
304 raise Exception("Could not find BFD session in VPP response")
308 def desired_min_tx(self):
309 """ desired minimum tx interval """
310 return self._desired_min_tx
313 def required_min_rx(self):
314 """ required minimum rx interval """
315 return self._required_min_rx
318 def detect_mult(self):
319 """ detect multiplier """
320 return self._detect_mult
325 return self._sha1_key
328 def bfd_key_id(self):
329 """ bfd key id in use """
330 return self._bfd_key_id
332 def activate_auth(self, key, bfd_key_id=None, delayed=False):
333 """ activate authentication for this session """
334 self._bfd_key_id = bfd_key_id if bfd_key_id else randint(0, 255)
336 is_ipv6 = 1 if AF_INET6 == self.af else 0
337 conf_key_id = self._sha1_key.conf_key_id
338 is_delayed = 1 if delayed else 0
339 self.test.vapi.bfd_udp_auth_activate(self._interface.sw_if_index,
343 bfd_key_id=self._bfd_key_id,
344 conf_key_id=conf_key_id,
345 is_delayed=is_delayed)
347 def deactivate_auth(self, delayed=False):
348 """ deactivate authentication """
349 self._bfd_key_id = None
350 self._sha1_key = None
351 is_delayed = 1 if delayed else 0
352 is_ipv6 = 1 if AF_INET6 == self.af else 0
353 self.test.vapi.bfd_udp_auth_deactivate(self._interface.sw_if_index,
357 is_delayed=is_delayed)
359 def modify_parameters(self,
362 required_min_rx=None):
363 """ modify session parameters """
365 self._detect_mult = detect_mult
367 self._desired_min_tx = desired_min_tx
369 self._required_min_rx = required_min_rx
370 is_ipv6 = 1 if AF_INET6 == self.af else 0
371 self.test.vapi.bfd_udp_mod(self._interface.sw_if_index,
373 self.required_min_rx,
379 def add_vpp_config(self):
380 is_ipv6 = 1 if AF_INET6 == self.af else 0
381 bfd_key_id = self._bfd_key_id if self._sha1_key else None
382 conf_key_id = self._sha1_key.conf_key_id if self._sha1_key else None
383 self.test.vapi.bfd_udp_add(self._interface.sw_if_index,
385 self.required_min_rx,
390 bfd_key_id=bfd_key_id,
391 conf_key_id=conf_key_id)
392 self._test.registry.register(self, self.test.logger)
394 def query_vpp_config(self):
395 session = self.get_bfd_udp_session_dump_entry()
396 return session is not None
398 def remove_vpp_config(self):
399 is_ipv6 = 1 if AF_INET6 == self._af else 0
400 self.test.vapi.bfd_udp_del(self._interface.sw_if_index,
406 return "bfd-udp-%s-%s-%s-%s" % (self._interface.sw_if_index,
412 return self.object_id()
415 """ set bfd session admin-up """
416 is_ipv6 = 1 if AF_INET6 == self._af else 0
417 self.test.vapi.bfd_udp_session_set_flags(1,
418 self._interface.sw_if_index,