blob: 84ef7b0ef4d749dcfeb7ea762d8ab668a9762562 [file] [log] [blame]
""" BFD protocol implementation """
from random import randint
from socket import AF_INET, AF_INET6, inet_pton
from scapy.all import bind_layers
from scapy.layers.inet import UDP
from scapy.packet import Packet
from scapy.fields import BitField, BitEnumField, XByteField, FlagsField,\
ConditionalField, StrField
from vpp_object import VppObject
from util import NumericConstant
class BFDDiagCode(NumericConstant):
""" BFD Diagnostic Code """
no_diagnostic = 0
control_detection_time_expired = 1
echo_function_failed = 2
neighbor_signaled_session_down = 3
forwarding_plane_reset = 4
path_down = 5
concatenated_path_down = 6
administratively_down = 7
reverse_concatenated_path_down = 8
desc_dict = {
no_diagnostic: "No diagnostic",
control_detection_time_expired: "Control Detection Time Expired",
echo_function_failed: "Echo Function Failed",
neighbor_signaled_session_down: "Neighbor Signaled Session Down",
forwarding_plane_reset: "Forwarding Plane Reset",
path_down: "Path Down",
concatenated_path_down: "Concatenated Path Down",
administratively_down: "Administratively Down",
reverse_concatenated_path_down: "Reverse Concatenated Path Down",
}
class BFDState(NumericConstant):
""" BFD State """
admin_down = 0
down = 1
init = 2
up = 3
desc_dict = {
admin_down: "AdminDown",
down: "Down",
init: "Init",
up: "Up",
}
class BFDAuthType(NumericConstant):
""" BFD Authentication Type """
no_auth = 0
simple_pwd = 1
keyed_md5 = 2
meticulous_keyed_md5 = 3
keyed_sha1 = 4
meticulous_keyed_sha1 = 5
desc_dict = {
no_auth: "No authentication",
simple_pwd: "Simple Password",
keyed_md5: "Keyed MD5",
meticulous_keyed_md5: "Meticulous Keyed MD5",
keyed_sha1: "Keyed SHA1",
meticulous_keyed_sha1: "Meticulous Keyed SHA1",
}
def bfd_is_auth_used(pkt):
""" is packet authenticated? """
return "A" in pkt.sprintf("%BFD.flags%")
def bfd_is_simple_pwd_used(pkt):
""" is simple password authentication used? """
return bfd_is_auth_used(pkt) and pkt.auth_type == BFDAuthType.simple_pwd
def bfd_is_sha1_used(pkt):
""" is sha1 authentication used? """
return bfd_is_auth_used(pkt) and pkt.auth_type in \
(BFDAuthType.keyed_sha1, BFDAuthType.meticulous_keyed_sha1)
def bfd_is_md5_used(pkt):
""" is md5 authentication used? """
return bfd_is_auth_used(pkt) and pkt.auth_type in \
(BFDAuthType.keyed_md5, BFDAuthType.meticulous_keyed_md5)
def bfd_is_md5_or_sha1_used(pkt):
""" is md5 or sha1 used? """
return bfd_is_md5_used(pkt) or bfd_is_sha1_used(pkt)
class BFD(Packet):
""" BFD protocol layer for scapy """
udp_dport = 3784 #: BFD destination port per RFC 5881
udp_dport_echo = 3785 # : BFD destination port for ECHO per RFC 5881
udp_sport_min = 49152 #: BFD source port min value per RFC 5881
udp_sport_max = 65535 #: BFD source port max value per RFC 5881
bfd_pkt_len = 24 # : length of BFD pkt without authentication section
sha1_auth_len = 28 # : length of authentication section if SHA1 used
name = "BFD"
fields_desc = [
BitField("version", 1, 3),
BitEnumField("diag", 0, 5, BFDDiagCode.desc_dict),
BitEnumField("state", 0, 2, BFDState.desc_dict),
FlagsField("flags", 0, 6, ['M', 'D', 'A', 'C', 'F', 'P']),
XByteField("detect_mult", 0),
BitField("length", bfd_pkt_len, 8),
BitField("my_discriminator", 0, 32),
BitField("your_discriminator", 0, 32),
BitField("desired_min_tx_interval", 0, 32),
BitField("required_min_rx_interval", 0, 32),
BitField("required_min_echo_rx_interval", 0, 32),
ConditionalField(
BitEnumField("auth_type", 0, 8, BFDAuthType.desc_dict),
bfd_is_auth_used),
ConditionalField(BitField("auth_len", 0, 8), bfd_is_auth_used),
ConditionalField(BitField("auth_key_id", 0, 8), bfd_is_auth_used),
ConditionalField(BitField("auth_reserved", 0, 8),
bfd_is_md5_or_sha1_used),
ConditionalField(
BitField("auth_seq_num", 0, 32), bfd_is_md5_or_sha1_used),
ConditionalField(StrField("auth_key_hash", "0" * 16), bfd_is_md5_used),
ConditionalField(
StrField("auth_key_hash", "0" * 20), bfd_is_sha1_used),
]
def mysummary(self):
return self.sprintf("BFD(my_disc=%BFD.my_discriminator%,"
"your_disc=%BFD.your_discriminator%)")
# glue the BFD packet class to scapy parser
bind_layers(UDP, BFD, dport=BFD.udp_dport)
class BFD_vpp_echo(Packet):
""" BFD echo packet as used by VPP (non-rfc, as rfc doesn't define one) """
udp_dport = 3785 #: BFD echo destination port per RFC 5881
name = "BFD_VPP_ECHO"
fields_desc = [
BitField("discriminator", 0, 32),
BitField("expire_time_clocks", 0, 64),
BitField("checksum", 0, 64)
]
def mysummary(self):
return self.sprintf(
"BFD_VPP_ECHO(disc=%BFD_VPP_ECHO.discriminator%,"
"expire_time_clocks=%BFD_VPP_ECHO.expire_time_clocks%)")
# glue the BFD echo packet class to scapy parser
bind_layers(UDP, BFD_vpp_echo, dport=BFD_vpp_echo.udp_dport)
class VppBFDAuthKey(VppObject):
""" Represents BFD authentication key in VPP """
def __init__(self, test, conf_key_id, auth_type, key):
self._test = test
self._key = key
self._auth_type = auth_type
test.assertIn(auth_type, BFDAuthType.desc_dict)
self._conf_key_id = conf_key_id
@property
def test(self):
""" Test which created this key """
return self._test
@property
def auth_type(self):
""" Authentication type for this key """
return self._auth_type
@property
def key(self):
""" key data """
return self._key
@key.setter
def key(self, value):
self._key = value
@property
def conf_key_id(self):
""" configuration key ID """
return self._conf_key_id
def add_vpp_config(self):
self.test.vapi.bfd_auth_set_key(
self._conf_key_id, self._auth_type, self._key)
self._test.registry.register(self, self.test.logger)
def get_bfd_auth_keys_dump_entry(self):
""" get the entry in the auth keys dump corresponding to this key """
result = self.test.vapi.bfd_auth_keys_dump()
for k in result:
if k.conf_key_id == self._conf_key_id:
return k
return None
def query_vpp_config(self):
return self.get_bfd_auth_keys_dump_entry() is not None
def remove_vpp_config(self):
self.test.vapi.bfd_auth_del_key(self._conf_key_id)
def object_id(self):
return "bfd-auth-key-%s" % self._conf_key_id
class VppBFDUDPSession(VppObject):
""" Represents BFD UDP session in VPP """
def __init__(self, test, interface, peer_addr, local_addr=None, af=AF_INET,
desired_min_tx=300000, required_min_rx=300000, detect_mult=3,
sha1_key=None, bfd_key_id=None):
self._test = test
self._interface = interface
self._af = af
self._local_addr = local_addr
if local_addr is not None:
self._local_addr_n = inet_pton(af, local_addr)
else:
self._local_addr_n = None
self._peer_addr = peer_addr
self._peer_addr_n = inet_pton(af, peer_addr)
self._desired_min_tx = desired_min_tx
self._required_min_rx = required_min_rx
self._detect_mult = detect_mult
self._sha1_key = sha1_key
if bfd_key_id is not None:
self._bfd_key_id = bfd_key_id
else:
self._bfd_key_id = randint(0, 255)
@property
def test(self):
""" Test which created this session """
return self._test
@property
def interface(self):
""" Interface on which this session lives """
return self._interface
@property
def af(self):
""" Address family - AF_INET or AF_INET6 """
return self._af
@property
def local_addr(self):
""" BFD session local address (VPP address) """
if self._local_addr is None:
if self.af == AF_INET:
return self._interface.local_ip4
elif self.af == AF_INET6:
return self._interface.local_ip6
else:
raise Exception("Unexpected af '%s'" % self.af)
return self._local_addr
@property
def local_addr_n(self):
""" BFD session local address (VPP address) - raw, suitable for API """
if self._local_addr is None:
if self.af == AF_INET:
return self._interface.local_ip4n
elif self.af == AF_INET6:
return self._interface.local_ip6n
else:
raise Exception("Unexpected af '%s'" % self.af)
return self._local_addr_n
@property
def peer_addr(self):
""" BFD session peer address """
return self._peer_addr
@property
def peer_addr_n(self):
""" BFD session peer address - raw, suitable for API """
return self._peer_addr_n
def get_bfd_udp_session_dump_entry(self):
""" get the namedtuple entry from bfd udp session dump """
result = self.test.vapi.bfd_udp_session_dump()
for s in result:
self.test.logger.debug("session entry: %s" % str(s))
if s.sw_if_index == self.interface.sw_if_index:
if self.af == AF_INET \
and s.is_ipv6 == 0 \
and self.interface.local_ip4n == s.local_addr[:4] \
and self.interface.remote_ip4n == s.peer_addr[:4]:
return s
if self.af == AF_INET6 \
and s.is_ipv6 == 1 \
and self.interface.local_ip6n == s.local_addr \
and self.interface.remote_ip6n == s.peer_addr:
return s
return None
@property
def state(self):
""" BFD session state """
session = self.get_bfd_udp_session_dump_entry()
if session is None:
raise Exception("Could not find BFD session in VPP response")
return session.state
@property
def desired_min_tx(self):
""" desired minimum tx interval """
return self._desired_min_tx
@property
def required_min_rx(self):
""" required minimum rx interval """
return self._required_min_rx
@property
def detect_mult(self):
""" detect multiplier """
return self._detect_mult
@property
def sha1_key(self):
""" sha1 key """
return self._sha1_key
@property
def bfd_key_id(self):
""" bfd key id in use """
return self._bfd_key_id
def activate_auth(self, key, bfd_key_id=None, delayed=False):
""" activate authentication for this session """
self._bfd_key_id = bfd_key_id if bfd_key_id else randint(0, 255)
self._sha1_key = key
is_ipv6 = 1 if AF_INET6 == self.af else 0
conf_key_id = self._sha1_key.conf_key_id
is_delayed = 1 if delayed else 0
self.test.vapi.bfd_udp_auth_activate(self._interface.sw_if_index,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6,
bfd_key_id=self._bfd_key_id,
conf_key_id=conf_key_id,
is_delayed=is_delayed)
def deactivate_auth(self, delayed=False):
""" deactivate authentication """
self._bfd_key_id = None
self._sha1_key = None
is_delayed = 1 if delayed else 0
is_ipv6 = 1 if AF_INET6 == self.af else 0
self.test.vapi.bfd_udp_auth_deactivate(self._interface.sw_if_index,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6,
is_delayed=is_delayed)
def modify_parameters(self,
detect_mult=None,
desired_min_tx=None,
required_min_rx=None):
""" modify session parameters """
if detect_mult:
self._detect_mult = detect_mult
if desired_min_tx:
self._desired_min_tx = desired_min_tx
if required_min_rx:
self._required_min_rx = required_min_rx
is_ipv6 = 1 if AF_INET6 == self.af else 0
self.test.vapi.bfd_udp_mod(self._interface.sw_if_index,
self.desired_min_tx,
self.required_min_rx,
self.detect_mult,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6)
def add_vpp_config(self):
is_ipv6 = 1 if AF_INET6 == self.af else 0
bfd_key_id = self._bfd_key_id if self._sha1_key else None
conf_key_id = self._sha1_key.conf_key_id if self._sha1_key else None
self.test.vapi.bfd_udp_add(self._interface.sw_if_index,
self.desired_min_tx,
self.required_min_rx,
self.detect_mult,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6,
bfd_key_id=bfd_key_id,
conf_key_id=conf_key_id)
self._test.registry.register(self, self.test.logger)
def query_vpp_config(self):
session = self.get_bfd_udp_session_dump_entry()
return session is not None
def remove_vpp_config(self):
is_ipv6 = 1 if AF_INET6 == self._af else 0
self.test.vapi.bfd_udp_del(self._interface.sw_if_index,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6)
def object_id(self):
return "bfd-udp-%s-%s-%s-%s" % (self._interface.sw_if_index,
self.local_addr,
self.peer_addr,
self.af)
def admin_up(self):
""" set bfd session admin-up """
is_ipv6 = 1 if AF_INET6 == self._af else 0
self.test.vapi.bfd_udp_session_set_flags(1,
self._interface.sw_if_index,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6)
def admin_down(self):
""" set bfd session admin-down """
is_ipv6 = 1 if AF_INET6 == self._af else 0
self.test.vapi.bfd_udp_session_set_flags(0,
self._interface.sw_if_index,
self.local_addr_n,
self.peer_addr_n,
is_ipv6=is_ipv6)