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_dport_echo = 3785 # : BFD destination port for ECHO per RFC 5881
114 udp_sport_min = 49152 #: BFD source port min value per RFC 5881
115 udp_sport_max = 65535 #: BFD source port max value per RFC 5881
116 bfd_pkt_len = 24 # : length of BFD pkt without authentication section
117 sha1_auth_len = 28 # : length of authentication section if SHA1 used
122 BitField("version", 1, 3),
123 BitEnumField("diag", 0, 5, BFDDiagCode.desc_dict),
124 BitEnumField("state", 0, 2, BFDState.desc_dict),
125 FlagsField("flags", 0, 6, ['M', 'D', 'A', 'C', 'F', 'P']),
126 XByteField("detect_mult", 0),
127 BitField("length", bfd_pkt_len, 8),
128 BitField("my_discriminator", 0, 32),
129 BitField("your_discriminator", 0, 32),
130 BitField("desired_min_tx_interval", 0, 32),
131 BitField("required_min_rx_interval", 0, 32),
132 BitField("required_min_echo_rx_interval", 0, 32),
134 BitEnumField("auth_type", 0, 8, BFDAuthType.desc_dict),
136 ConditionalField(BitField("auth_len", 0, 8), bfd_is_auth_used),
137 ConditionalField(BitField("auth_key_id", 0, 8), bfd_is_auth_used),
138 ConditionalField(BitField("auth_reserved", 0, 8),
139 bfd_is_md5_or_sha1_used),
141 BitField("auth_seq_num", 0, 32), bfd_is_md5_or_sha1_used),
142 ConditionalField(StrField("auth_key_hash", "0" * 16), bfd_is_md5_used),
144 StrField("auth_key_hash", "0" * 20), bfd_is_sha1_used),
148 return self.sprintf("BFD(my_disc=%BFD.my_discriminator%,"
149 "your_disc=%BFD.your_discriminator%)")
151 # glue the BFD packet class to scapy parser
152 bind_layers(UDP, BFD, dport=BFD.udp_dport)
155 class BFD_vpp_echo(Packet):
156 """ BFD echo packet as used by VPP (non-rfc, as rfc doesn't define one) """
158 udp_dport = 3785 #: BFD echo destination port per RFC 5881
159 name = "BFD_VPP_ECHO"
162 BitField("discriminator", 0, 32),
163 BitField("expire_time_clocks", 0, 64),
164 BitField("checksum", 0, 64)
169 "BFD_VPP_ECHO(disc=%BFD_VPP_ECHO.discriminator%,"
170 "expire_time_clocks=%BFD_VPP_ECHO.expire_time_clocks%)")
172 # glue the BFD echo packet class to scapy parser
173 bind_layers(UDP, BFD_vpp_echo, dport=BFD_vpp_echo.udp_dport)
176 class VppBFDAuthKey(VppObject):
177 """ Represents BFD authentication key in VPP """
179 def __init__(self, test, conf_key_id, auth_type, key):
182 self._auth_type = auth_type
183 test.assertIn(auth_type, BFDAuthType.desc_dict)
184 self._conf_key_id = conf_key_id
188 """ Test which created this key """
193 """ Authentication type for this key """
194 return self._auth_type
202 def key(self, value):
206 def conf_key_id(self):
207 """ configuration key ID """
208 return self._conf_key_id
210 def add_vpp_config(self):
211 self.test.vapi.bfd_auth_set_key(
212 self._conf_key_id, self._auth_type, self._key)
213 self._test.registry.register(self, self.test.logger)
215 def get_bfd_auth_keys_dump_entry(self):
216 """ get the entry in the auth keys dump corresponding to this key """
217 result = self.test.vapi.bfd_auth_keys_dump()
219 if k.conf_key_id == self._conf_key_id:
223 def query_vpp_config(self):
224 return self.get_bfd_auth_keys_dump_entry() is not None
226 def remove_vpp_config(self):
227 self.test.vapi.bfd_auth_del_key(self._conf_key_id)
230 return "bfd-auth-key-%s" % self._conf_key_id
233 return self.object_id()
236 class VppBFDUDPSession(VppObject):
237 """ Represents BFD UDP session in VPP """
239 def __init__(self, test, interface, peer_addr, local_addr=None, af=AF_INET,
240 desired_min_tx=300000, required_min_rx=300000, detect_mult=3,
241 sha1_key=None, bfd_key_id=None):
243 self._interface = interface
245 self._local_addr = local_addr
246 if local_addr is not None:
247 self._local_addr_n = inet_pton(af, local_addr)
249 self._local_addr_n = None
250 self._peer_addr = peer_addr
251 self._peer_addr_n = inet_pton(af, peer_addr)
252 self._desired_min_tx = desired_min_tx
253 self._required_min_rx = required_min_rx
254 self._detect_mult = detect_mult
255 self._sha1_key = sha1_key
256 if bfd_key_id is not None:
257 self._bfd_key_id = bfd_key_id
259 self._bfd_key_id = randint(0, 255)
263 """ Test which created this session """
268 """ Interface on which this session lives """
269 return self._interface
273 """ Address family - AF_INET or AF_INET6 """
277 def local_addr(self):
278 """ BFD session local address (VPP address) """
279 if self._local_addr is None:
280 if self.af == AF_INET:
281 return self._interface.local_ip4
282 elif self.af == AF_INET6:
283 return self._interface.local_ip6
285 raise Exception("Unexpected af '%s'" % self.af)
286 return self._local_addr
289 def local_addr_n(self):
290 """ BFD session local address (VPP address) - raw, suitable for API """
291 if self._local_addr is None:
292 if self.af == AF_INET:
293 return self._interface.local_ip4n
294 elif self.af == AF_INET6:
295 return self._interface.local_ip6n
297 raise Exception("Unexpected af '%s'" % self.af)
298 return self._local_addr_n
302 """ BFD session peer address """
303 return self._peer_addr
306 def peer_addr_n(self):
307 """ BFD session peer address - raw, suitable for API """
308 return self._peer_addr_n
310 def get_bfd_udp_session_dump_entry(self):
311 """ get the namedtuple entry from bfd udp session dump """
312 result = self.test.vapi.bfd_udp_session_dump()
314 self.test.logger.debug("session entry: %s" % str(s))
315 if s.sw_if_index == self.interface.sw_if_index:
316 if self.af == AF_INET \
318 and self.interface.local_ip4n == s.local_addr[:4] \
319 and self.interface.remote_ip4n == s.peer_addr[:4]:
321 if self.af == AF_INET6 \
323 and self.interface.local_ip6n == s.local_addr \
324 and self.interface.remote_ip6n == s.peer_addr:
330 """ BFD session state """
331 session = self.get_bfd_udp_session_dump_entry()
333 raise Exception("Could not find BFD session in VPP response")
337 def desired_min_tx(self):
338 """ desired minimum tx interval """
339 return self._desired_min_tx
342 def required_min_rx(self):
343 """ required minimum rx interval """
344 return self._required_min_rx
347 def detect_mult(self):
348 """ detect multiplier """
349 return self._detect_mult
354 return self._sha1_key
357 def bfd_key_id(self):
358 """ bfd key id in use """
359 return self._bfd_key_id
361 def activate_auth(self, key, bfd_key_id=None, delayed=False):
362 """ activate authentication for this session """
363 self._bfd_key_id = bfd_key_id if bfd_key_id else randint(0, 255)
365 is_ipv6 = 1 if AF_INET6 == self.af else 0
366 conf_key_id = self._sha1_key.conf_key_id
367 is_delayed = 1 if delayed else 0
368 self.test.vapi.bfd_udp_auth_activate(self._interface.sw_if_index,
372 bfd_key_id=self._bfd_key_id,
373 conf_key_id=conf_key_id,
374 is_delayed=is_delayed)
376 def deactivate_auth(self, delayed=False):
377 """ deactivate authentication """
378 self._bfd_key_id = None
379 self._sha1_key = None
380 is_delayed = 1 if delayed else 0
381 is_ipv6 = 1 if AF_INET6 == self.af else 0
382 self.test.vapi.bfd_udp_auth_deactivate(self._interface.sw_if_index,
386 is_delayed=is_delayed)
388 def modify_parameters(self,
391 required_min_rx=None):
392 """ modify session parameters """
394 self._detect_mult = detect_mult
396 self._desired_min_tx = desired_min_tx
398 self._required_min_rx = required_min_rx
399 is_ipv6 = 1 if AF_INET6 == self.af else 0
400 self.test.vapi.bfd_udp_mod(self._interface.sw_if_index,
402 self.required_min_rx,
408 def add_vpp_config(self):
409 is_ipv6 = 1 if AF_INET6 == self.af else 0
410 bfd_key_id = self._bfd_key_id if self._sha1_key else None
411 conf_key_id = self._sha1_key.conf_key_id if self._sha1_key else None
412 self.test.vapi.bfd_udp_add(self._interface.sw_if_index,
414 self.required_min_rx,
419 bfd_key_id=bfd_key_id,
420 conf_key_id=conf_key_id)
421 self._test.registry.register(self, self.test.logger)
423 def query_vpp_config(self):
424 session = self.get_bfd_udp_session_dump_entry()
425 return session is not None
427 def remove_vpp_config(self):
428 is_ipv6 = 1 if AF_INET6 == self._af else 0
429 self.test.vapi.bfd_udp_del(self._interface.sw_if_index,
435 return "bfd-udp-%s-%s-%s-%s" % (self._interface.sw_if_index,
441 return self.object_id()
444 """ set bfd session admin-up """
445 is_ipv6 = 1 if AF_INET6 == self._af else 0
446 self.test.vapi.bfd_udp_session_set_flags(1,
447 self._interface.sw_if_index,
452 def admin_down(self):
453 """ set bfd session admin-down """
454 is_ipv6 = 1 if AF_INET6 == self._af else 0
455 self.test.vapi.bfd_udp_session_set_flags(0,
456 self._interface.sw_if_index,