Wireshark-bugs: [Wireshark-bugs] [Bug 11650] New: Improvements to dissection of BGP EVPN routes

Date: Wed, 28 Oct 2015 22:00:27 +0000
Bug ID 11650
Summary Improvements to dissection of BGP EVPN routes
Product Wireshark
Version unspecified
Hardware x86-64
OS Debian
Status UNCONFIRMED
Severity Enhancement
Priority Low
Component Dissection engine (libwireshark)
Assignee [email protected]
Reporter [email protected]

Created attachment 13953 [details]
One .pcap with EVPN route types 1,3 and 4; another one with EVPN route type 2.
Also five text files with the same routes in text format.

Build Information:
tshark -v
TShark (Wireshark) 2.1.0-283-g9b3bda9 (Git Rev Unknown from unknown)

Copyright 1998-2015 Gerald Combs <[email protected]> and contributors.
License GPLv2+: GNU GPL version 2 or later
<http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Compiled (64-bit) with libpcap, without POSIX capabilities, without libnl, with
libz 1.2.8, with GLib 2.42.1, without SMI, without c-ares, without ADNS,
without
Lua, without GnuTLS, without Gcrypt, without Kerberos, without GeoIP.

Running on Linux 3.16.0-4-amd64, with locale en_US.UTF-8, with libpcap version
1.6.2, with libz 1.2.8.
Intel(R) Core(TM) i7-4800MQ CPU @ 2.70GHz (with SSE4.2)

Built using gcc 4.9.2.
--
There are several proposals to improve representation of BGP EVPN routes (RFC
7432):

1) Ethernet A-D Route:

a) NLRI: (See attached file bgp-evpn-route-type-1-(auto-discovery)-example-1)

ESI Field - it is proposed to enhance description of this field in accordance
with RFC 7432, section 5.

MPLS Label Field - when MPLS Label value is non-zero, there is comment that
Bottom of Stack is not set. Per RFC 7432, section 7.1, there is no BoS bit
within MPLS Label field. I.e. label is encoded NOT the same way as it is done
in RFC 3107 (and RFC 3032).

b) BGP Tunnel Encapsulation Attribute Extended Community: (See attached file
bgp-evpn-route-type-1-(auto-discovery)-example-1)

Current Representation:

Community Transitive Opaque Encapsulation: 0x00 0x000a
  Community type high: Transitive Opaque (0x03)
  Subtype opaque: Encapsulation (0x0c)
  Two octets Value specific: 0x0000
  Four octets Value specific: 0x0000000a

Proposed representation (per RFC 5512, section 4.5)

Community Transitive Opaque Encapsulation: 0x0a (MPLS)
  Community type high: Transitive Opaque (0x03)
  Subtype opaque: Encapsulation (0x0c)
  Reserved: 0x00000000
  Tunnel Type: 0x000a (MPLS) (per
http://www.iana.org/assignments/bgp-parameters/bgp-parameters.xhtml#tunnel-types)

c) ESI Label Extended Community (See attached file
bgp-evpn-route-type-1-(auto-discovery)-example-2)

Deconding of this attribute could be done in accordance with RFC 7432, section
7.5.

Current representation:

Community Transitive EVPN ESI MPLS Label: 0x100 0x3fffc0
  Community type high: Transitive EVPN (0x06)
  Subtype evpn: ESI MPLS Label (0x01)
  Two octets Value specific: 0x100003f
  Four octets Value specific: 0x0000ffc0

Proposed representation:

Community Transitive EVPN ESI MPLS Label: 0x100 0x3fffc0
  Community type high: Transitive EVPN (0x06)
  Subtype evpn: ESI MPLS Label (0x01)
  Flags:0x01:
  .... ...1: Single-Active Multi-Homing
  Reserved: 0x0000
  ESI Label: 0x3ffc0 (262140)

2) MAC Advertisement route: (See attached file bgp-epvn-route-type-2-(mac))

The same proposals for ESI and MPLS Label of NLRI as well as for BGP Tunnel
Encapsulation Attribute as described above for 1)

3) Inclusive Multicast Ethernet Tag Route (See attached file
bgp-epvn-route-type-3-(inclusive)):

The same for BGP Tunnel Encapsulation Attribute as described above for 1).
Also, for BGP PMSI_TUNNEL_ATTRIBUTE - the same as above for MPLS Label field -
BoS bit is not used (RFC 6514, Section 5).

4) Ethernet Segment Route (See attached file
bgp-epvn-route-type-4-(ethernet-segment)):

NLRI - the same proposal for representation of ESI as above for 1)

ES Import Extended Community - proposal is to decode it in accordance with RFC
7432, section 7.6.

Current representation:

Community Transitive EVPN ES Import: 0x00 0x0001
  Community type high: Transitive EVPN (0x06)
  Subtype evpn: ES Import (0x02)
  Two octets Value specific: 0x0000
  Four octets Value specific: 0x00000001

Proposed representation:

Community Transitive EVPN ES Import: 0x00 0x0001
  Community type high: Transitive EVPN (0x06)
  Subtype evpn: ES Import (0x02)
  Route Target: 0x000000000001 (00:00:00:00:00:01)


You are receiving this mail because:
  • You are watching all bug changes.