def unpack(afi, safi, data):
len_in_bits = ord(data[0])
data = data[1:]
if (len_in_bits == 0):
return RouteTargetConstraint(afi, safi, ASN(0), None)
if (len_in_bits < 4):
raise Exception("RTC route too short to be decoded")
asn = ASN(unpack('!L', data[0:4])[0])
data = data[4:]
rt = RouteTarget.unpackFrom(data)
return RouteTargetConstraint(afi, safi, asn, rt)
class Open (Message):
TYPE = chr(0x01)
def __init__ (self,version,asn,router_id,capabilities,hold_time):
self.version = Version(version)
self.asn = ASN(asn)
self.hold_time = HoldTime(hold_time)
self.router_id = RouterID(router_id)
self.capabilities = capabilities
def message (self):
if self.asn.asn4():
return self._message("%s%s%s%s%s" % (self.version.pack(),ASN(23456).pack(False),self.hold_time.pack(),self.router_id.pack(),self.capabilities.pack()))
return self._message("%s%s%s%s%s" % (self.version.pack(),self.asn.pack(False),self.hold_time.pack(),self.router_id.pack(),self.capabilities.pack()))
def __str__ (self):
return "OPEN version=%d asn=%d hold_time=%s router_id=%s capabilities=[%s]" % (self.version, self.asn, self.hold_time, self.router_id,self.capabilities)
def unpackFrom(data):
type_ = ord(data[0]) & 0x0F
stype = ord(data[1])
data = data[2:]
if stype == 0x02: #FIXME, unclean
if type_ in (0x00, 0x02):
asn, number = unpack('!HL', data[:6])
return RouteTarget(ASN(asn), None, number)
if type_ == 0x01:
ip = socket.inet_ntop(data[0:4])
number = unpack('!H', data[4:6])[0]
return RouteTarget(None, ip, number)
def CapabilitiesFactory(self, data):
capabilities = Capabilities()
option_len = ord(data[0])
if option_len:
data = data[1:]
while data:
key, value, data = self._key_values('parameter', data)
# Paramaters must only be sent once.
if key == Parameter.AUTHENTIFICATION_INFORMATION:
raise Notify(2, 5)
if key == Parameter.CAPABILITIES:
while value:
k, capv, value = self._key_values('capability', value)
# Multiple Capabilities can be present in a single attribute
#if r:
# raise Notify(2,0,"Bad length for OPEN %s (size mismatch) %s" % ('capability',hexa(value)))
if k == Capabilities.MULTIPROTOCOL_EXTENSIONS:
if k not in capabilities:
capabilities[k] = MultiProtocol()
afi = AFI(unpack('!H', capv[:2])[0])
safi = SAFI(ord(capv[3]))
capabilities[k].append((afi, safi))
continue
if k == Capabilities.GRACEFUL_RESTART:
restart = unpack('!H', capv[:2])[0]
restart_flag = restart >> 12
restart_time = restart & Graceful.TIME_MASK
value_gr = capv[2:]
families = []
while value_gr:
afi = AFI(unpack('!H', value_gr[:2])[0])
safi = SAFI(ord(value_gr[2]))
flag_family = ord(value_gr[0])
families.append((afi, safi, flag_family))
value_gr = value_gr[4:]
capabilities[k] = Graceful(restart_flag,
restart_time, families)
continue
if k == Capabilities.FOUR_BYTES_ASN:
capabilities[k] = ASN(unpack('!L', capv[:4])[0])
continue
if k == Capabilities.ROUTE_REFRESH:
capabilities[k] = RouteRefresh()
continue
if k == Capabilities.CISCO_ROUTE_REFRESH:
capabilities[k] = CiscoRouteRefresh()
continue
if k == Capabilities.MULTISESSION_BGP:
capabilities[k] = MultiSession()
continue
if k == Capabilities.MULTISESSION_BGP_RFC:
capabilities[k] = MultiSession()
continue
if k not in capabilities:
capabilities[k] = Unknown(k,
[ord(_) for _ in capv])
else:
raise Notify(2, 0, 'Unknown OPEN parameter %s' % hex(key))
return capabilities
def __init__ (self,version,asn,router_id,capabilities,hold_time): self.version = Version(version) self.asn = ASN(asn) self.hold_time = HoldTime(hold_time) self.router_id = RouterID(router_id) self.capabilities = capabilities
