openstack/os-ken
Code Issues Proposed changes

packet.bgp: implement RFC 4893

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Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
This commit is contained in:
YAMAMOTO Takashi 2013-10-01 15:49:38 +09:00 committed by FUJITA Tomonori
parent 95a1cfbba2
commit 3151190870
2 changed files with 44 additions and 9 deletions
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49
ryu/lib/packet/bgp.py
View File

@ -71,6 +71,10 @@ BGP_ATTR_TYPE_ATOMIC_AGGREGATE = 6 # 0 bytes
BGP_ATTR_TYPE_AGGREGATOR = 7 # AS number and IPv4 address
BGP_ATTR_TYPE_MP_REACH_NLRI = 14 # RFC 4760
BGP_ATTR_TYPE_MP_UNREACH_NLRI = 15 # RFC 4760
BGP_ATTR_TYPE_AS4_PATH = 17 # RFC 4893
BGP_ATTR_TYPE_AS4_AGGREGATOR = 18 # RFC 4893
AS_TRANS = 23456 # RFC 4893
def pad(bin, len_):
@ -247,12 +251,11 @@ class BGPPathAttributeOrigin(_PathAttribute):
_ATTR_FLAGS = BGP_ATTR_FLAG_TRANSITIVE
@_PathAttribute.register_type(BGP_ATTR_TYPE_AS_PATH)
class BGPPathAttributeAsPath(_PathAttribute):
class _BGPPathAttributeAsPathCommon(_PathAttribute):
_AS_SET = 1
_AS_SEQUENCE = 2
_SEG_HDR_PACK_STR = '!BB'
_AS_PACK_STR = '!H'
_AS_PACK_STR = None
_ATTR_FLAGS = BGP_ATTR_FLAG_TRANSITIVE
@classmethod
@ -296,6 +299,24 @@ class BGPPathAttributeAsPath(_PathAttribute):
return buf
@_PathAttribute.register_type(BGP_ATTR_TYPE_AS_PATH)
class BGPPathAttributeAsPath(_BGPPathAttributeAsPathCommon):
# XXX currently this implementation assumes 16 bit AS numbers.
# depends on negotiated capability, AS numbers can be 32 bit.
# while wireshark seems to attempt auto-detect, it seems that
# there's no way to detect it reliably. for example, the
# following byte sequence can be interpreted in two ways.
# 01 02 99 88 77 66 02 01 55 44
# AS_SET num=2 9988 7766 AS_SEQUENCE num=1 5544
# AS_SET num=2 99887766 02015544
_AS_PACK_STR = '!H'
@_PathAttribute.register_type(BGP_ATTR_TYPE_AS4_PATH)
class BGPPathAttributeAs4Path(_BGPPathAttributeAsPathCommon):
_AS_PACK_STR = '!I'
@_PathAttribute.register_type(BGP_ATTR_TYPE_NEXT_HOP)
class BGPPathAttributeNextHop(_PathAttribute):
_VALUE_PACK_STR = '!4s'
@ -337,15 +358,14 @@ class BGPPathAttributeAtomicAggregate(_PathAttribute):
return ''
@_PathAttribute.register_type(BGP_ATTR_TYPE_AGGREGATOR)
class BGPPathAttributeAggregator(_PathAttribute):
_VALUE_PACK_STR = '!H4s'
class _BGPPathAttributeAggregatorCommon(_PathAttribute):
_VALUE_PACK_STR = None
_ATTR_FLAGS = BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANSITIVE
def __init__(self, as_number, ip_addr, flags=0, type_=None, length=None):
super(BGPPathAttributeAggregator, self).__init__(flags=flags,
type_=type_,
length=length)
super(_BGPPathAttributeAggregatorCommon, self).__init__(flags=flags,
type_=type_,
length=length)
self.as_number = as_number
self.ip_addr = ip_addr
@ -365,6 +385,17 @@ class BGPPathAttributeAggregator(_PathAttribute):
return buf
@_PathAttribute.register_type(BGP_ATTR_TYPE_AGGREGATOR)
class BGPPathAttributeAggregator(_BGPPathAttributeAggregatorCommon):
# XXX currently this implementation assumes 16 bit AS numbers.
_VALUE_PACK_STR = '!H4s'
@_PathAttribute.register_type(BGP_ATTR_TYPE_AS4_AGGREGATOR)
class BGPPathAttributeAs4Aggregator(_BGPPathAttributeAggregatorCommon):
_VALUE_PACK_STR = '!I4s'
class BGPNLRI(_IPAddrPrefix):
pass

4
ryu/tests/unit/packet/test_bgp.py
View File

@ -78,6 +78,10 @@ class Test_bgp(unittest.TestCase):
bgp.BGPPathAttributeAtomicAggregate(),
bgp.BGPPathAttributeAggregator(as_number=40000,
ip_addr='192.0.2.99'),
bgp.BGPPathAttributeAs4Path(value=[[1000000], set([1000001, 1002]),
[1003, 1000004]]),
bgp.BGPPathAttributeAs4Aggregator(as_number=100040000,
ip_addr='192.0.2.99'),
bgp.BGPPathAttributeUnknown(flags=0, type_=100, value=300*'bar')
]
nlri = [