def add(self, attribute, _=None):
# we return None as attribute if the unpack code must not generate them
if attribute is None:
return
self._str = ''
self._json = ''
# XXX: FIXME: I am not sure anymore that more than one of each is possible
if attribute.ID in Attributes.MULTIPLE:
# deadcode: setdefault does not seem to exist anywhere ? (TM)
self.setdefault(attribute.ID, []).append(attribute)
# elif attribute.ID in (Attribute.CODE.COMMUNITY, Attribute.CODE.EXTENDED_COMMUNITY):
# if attribute.ID not in self:
# self[attribute.ID] = Attribute.klass(attribute.ID,attribute.FLAG)()
# self[attribute.ID].add(attribute)
elif attribute.ID in self:
# For flows we can add extended-communities using special keywords and extended-community
# This allows this trick
if attribute.ID != Attribute.CODE.EXTENDED_COMMUNITY:
raise Notify(
3, 0, 'multiple attribute for %s' %
str(Attribute.CODE(attribute.ID)))
for community in attribute.communities:
self[attribute.ID].add(community)
else:
self[attribute.ID] = attribute
def parse(self, data, negotiated):
if not data:
return self
# We do not care if the attribute are transitive or not as we do not redistribute
flag = Attribute.Flag(ord(data[0]))
aid = Attribute.CODE(ord(data[1]))
if flag & Attribute.Flag.EXTENDED_LENGTH:
length = unpack('!H', data[2:4])[0]
offset = 4
else:
length = ord(data[2])
offset = 3
data = data[offset:]
left = data[length:]
attribute = data[:length]
logger = Logger()
logger.parser(
LazyFormat(
"parsing flag %x type %02x (%s) len %02x %s" %
(flag, int(aid), aid, length, 'payload ' if length else ''),
data[:length]))
# remove the PARTIAL bit before comparaison if the attribute is optional
if aid in Attribute.attributes_optional:
aid &= Attribute.Flag.MASK_PARTIAL & 0xFF
# aid &= ~Attribute.Flag.PARTIAL & 0xFF # cleaner than above (python use signed integer for ~)
# handle the attribute if we know it
if Attribute.registered(aid, flag):
self.add(Attribute.unpack(aid, flag, attribute, negotiated))
return self.parse(left, negotiated)
# XXX: FIXME: we could use a fallback function here like capability
# if we know the attribute but the flag is not what the RFC says. ignore it.
if aid in Attribute.attributes_known:
logger.parser(
'invalid flag for attribute %s (flag 0x%02X, aid 0x%02X)' %
(Attribute.CODE.names.get(aid, 'unset'), flag, aid))
return self.parse(left, negotiated)
# it is an unknown transitive attribute we need to pass on
if flag & Attribute.Flag.TRANSITIVE:
logger.parser(
'unknown transitive attribute (flag 0x%02X, aid 0x%02X)' %
(flag, aid))
self.add(
GenericAttribute(aid, flag | Attribute.Flag.PARTIAL,
attribute), attribute)
return self.parse(left, negotiated)
# it is an unknown non-transitive attribute we can ignore.
logger.parser(
'ignoring unknown non-transitive attribute (flag 0x%02X, aid 0x%02X)'
% (flag, aid))
return self.parse(left, negotiated)
def flag_attribute_content(data):
flag = Attribute.Flag(ord(data[0]))
attr = Attribute.CODE(ord(data[1]))
if flag & Attribute.Flag.EXTENDED_LENGTH:
length = unpack('!H', data[2:4])[0]
return flag, attr, data[4:length + 4]
else:
length = ord(data[2])
return flag, attr, data[3:length + 3]
def add(self, attribute, _=None):
# we return None as attribute if the unpack code must not generate them
if attribute is None:
return
self._str = ''
self._json = ''
# XXX: FIXME: I am not sure anymore that more than one of each is possible
if attribute.ID in Attributes.MULTIPLE:
self.setdefault(attribute.ID, []).append(attribute)
elif attribute.ID in self:
raise Notify(
3, 0, 'multiple attribute for %s' %
str(Attribute.CODE(attribute.ID)))
else:
self[attribute.ID] = attribute
def add(self, attribute, _=None):
# we return None as attribute if the unpack code must not generate them
if attribute is None:
return
self._str = ''
self._json = ''
if attribute.MULTIPLE:
if self.has(attribute.ID):
self[attribute.ID].append(attribute)
else:
self[attribute.ID] = MultiAttributes(attribute)
else:
if attribute.ID in self:
raise Notify(
3, 0, 'multiple attribute for %s' %
str(Attribute.CODE(attribute.ID)))
else:
self[attribute.ID] = attribute
def parse(self, data, negotiated):
if not data:
return self
try:
# We do not care if the attribute are transitive or not as we do not redistribute
flag = Attribute.Flag(ord(data[0]))
aid = Attribute.CODE(ord(data[1]))
except IndexError:
self.add(TreatAsWithdraw())
return self
try:
offset = 3
length = ord(data[2])
if flag & Attribute.Flag.EXTENDED_LENGTH:
offset = 4
length = (length << 8) + ord(data[3])
except IndexError:
self.add(TreatAsWithdraw(aid))
return self
data = data[offset:]
left = data[length:]
attribute = data[:length]
logger = Logger()
logger.parser(LazyAttribute(flag, aid, length, data[:length]))
# remove the PARTIAL bit before comparaison if the attribute is optional
if aid in Attribute.attributes_optional:
flag &= Attribute.Flag.MASK_PARTIAL & 0xFF
# flag &= ~Attribute.Flag.PARTIAL & 0xFF # cleaner than above (python use signed integer for ~)
if aid in self:
if aid in self.NO_DUPLICATE:
raise Notify(
3, 1, 'multiple attribute for %s' %
str(Attribute.CODE(attribute.ID)))
logger.parser(
'duplicate attribute %s (flag 0x%02X, aid 0x%02X) skipping' %
(Attribute.CODE.names.get(aid, 'unset'), flag, aid))
return self.parse(left, negotiated)
# handle the attribute if we know it
if Attribute.registered(aid, flag):
if length == 0 and aid not in self.VALID_ZERO:
self.add(TreatAsWithdraw(aid))
return self.parse(left, negotiated)
try:
decoded = Attribute.unpack(aid, flag, attribute, negotiated)
except IndexError, exc:
if aid in self.TREAT_AS_WITHDRAW:
decoded = TreatAsWithdraw(aid)
else:
raise exc
except Notify, exc:
if aid in self.TREAT_AS_WITHDRAW:
decoded = TreatAsWithdraw()
elif aid in self.DISCARD:
decoded = Discard()
else:
raise exc
def parse(self, data, direction, negotiated):
if not data:
return self
try:
# We do not care if the attribute are transitive or not as we do not redistribute
flag = Attribute.Flag(data[0])
aid = Attribute.CODE(data[1])
except IndexError:
self.add(TreatAsWithdraw())
return self
try:
offset = 3
length = data[2]
if flag & Attribute.Flag.EXTENDED_LENGTH:
offset = 4
length = (length << 8) + data[3]
except IndexError:
self.add(TreatAsWithdraw(aid))
return self
data = data[offset:]
left = data[length:]
attribute = data[:length]
logfunc.debug(lazyattribute(flag, aid, length, data[:length]), 'parser')
# remove the PARTIAL bit before comparaison if the attribute is optional
if aid in Attribute.attributes_optional:
flag &= Attribute.Flag.MASK_PARTIAL & 0xFF
# flag &= ~Attribute.Flag.PARTIAL & 0xFF # cleaner than above (python use signed integer for ~)
if aid in self:
if aid in self.NO_DUPLICATE:
raise Notify(3, 1, 'multiple attribute for %s' % str(Attribute.CODE(attribute.ID)))
log.debug(
'duplicate attribute %s (flag 0x%02X, aid 0x%02X) skipping'
% (Attribute.CODE.names.get(aid, 'unset'), flag, aid),
'parser',
)
return self.parse(left, direction, negotiated)
# handle the attribute if we know it
if Attribute.registered(aid, flag):
if length == 0 and aid not in self.VALID_ZERO:
self.add(TreatAsWithdraw(aid))
return self.parse(left, direction, negotiated)
try:
decoded = Attribute.unpack(aid, flag, attribute, direction, negotiated)
except IndexError as exc:
if aid in self.TREAT_AS_WITHDRAW:
decoded = TreatAsWithdraw(aid)
else:
raise exc
except Notify as exc:
if aid in self.TREAT_AS_WITHDRAW:
decoded = TreatAsWithdraw()
elif aid in self.DISCARD:
decoded = Discard()
else:
raise exc
self.add(decoded)
return self.parse(left, direction, negotiated)
# XXX: FIXME: we could use a fallback function here like capability
# if we know the attribute but the flag is not what the RFC says.
if aid in Attribute.attributes_known:
if aid in self.TREAT_AS_WITHDRAW:
log.debug(
'invalid flag for attribute %s (flag 0x%02X, aid 0x%02X) treat as withdraw'
% (Attribute.CODE.names.get(aid, 'unset'), flag, aid),
'parser',
)
self.add(TreatAsWithdraw())
if aid in self.DISCARD:
log.debug(
'invalid flag for attribute %s (flag 0x%02X, aid 0x%02X) discard'
% (Attribute.CODE.names.get(aid, 'unset'), flag, aid),
'parser',
)
return self.parse(left, direction, negotiated)
# XXX: Check if we are missing any
log.debug(
'invalid flag for attribute %s (flag 0x%02X, aid 0x%02X) unspecified (should not happen)'
% (Attribute.CODE.names.get(aid, 'unset'), flag, aid),
'parser',
)
return self.parse(left, direction, negotiated)
# it is an unknown transitive attribute we need to pass on
if flag & Attribute.Flag.TRANSITIVE:
log.debug('unknown transitive attribute (flag 0x%02X, aid 0x%02X)' % (flag, aid), 'parser')
try:
decoded = GenericAttribute(aid, flag | Attribute.Flag.PARTIAL, attribute)
except IndexError:
decoded = TreatAsWithdraw(aid)
self.add(decoded, attribute)
return self.parse(left, direction, negotiated)
# it is an unknown non-transitive attribute we can ignore.
log.debug('ignoring unknown non-transitive attribute (flag 0x%02X, aid 0x%02X)' % (flag, aid), 'parser')
return self.parse(left, direction, negotiated)
