Regression in BGP flow spec generation code with ports, destination ports, source ports and packet-length

[pavel-odintsov]

Hello!

I've found regression in BGP flow spec generation code with ports, destination ports, source ports and packet-length.

Each of this announces could not be parsed with ExaBGP with following message:

Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        | could not parse the message
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        | Traceback (most recent call last):
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/configuration/check.py", line 240, in check_update
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     update = Update.unpack_message(injected,negotiated)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/__init__.py", line 263, in unpack_message
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     attributes = Attributes.unpack(_attributes,negotiated)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/attribute/attributes.py", line 266, in unpack
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     attributes = cls().parse(data,negotiated)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/attribute/attributes.py", line 324, in parse
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     return self.parse(left,negotiated)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/attribute/attributes.py", line 323, in parse
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     self.add(Attribute.unpack(aid,flag,attribute,negotiated))
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/attribute/attribute.py", line 237, in unpack
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     instance = cls.klass(attribute_id,flag).unpack(data,negotiated)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/attribute/mprnlri.py", line 194, in unpack
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     nlri,left = NLRI.unpack_nlri(afi,safi,data,IN.ANNOUNCED,addpath)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/nlri/nlri.py", line 102, in unpack_nlri
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     return cls.registered_nlri[key].unpack_nlri(afi,safi,data,action,addpath)
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |   File "/opt/dps/libraries/exabgp_git/lib/exabgp/bgp/message/update/nlri/flow.py", line 616, in unpack_nlri
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        |     raise Notify(3,10,'invalid length at the start of the the flow')
Tue, 08 Mar 2016 18:18:59 | INFO     | 24324  | parser        | Notify: UPDATE message error / Invalid Network Field / invalid length at the start of the the flow

[fujita]

Sorry about that. Can you share your code to generate them?

[pavel-odintsov]

Please do not apologize! :)

I've checked my test code... Will try to divide it.

We definitely have issue with following announces:

match port 8888 then discard
match port 8888 1122 then discard
match source-port 7171 then discard
match source-port 7171 2233 then discard

[pavel-odintsov]

I've wrote stub code for this: https://gist.github.com/pavel-odintsov/070eeb8ffece8f07de63

[fujita]

Can you try the latest?

[pavel-odintsov]

Awesome :) All test passed correctly!