[j-nsp] BMP and IPv6

[Vincent Bernat]

 ❦  6 décembre 2017 10:01 +0100, Vincent Bernat <bernat at luffy.cx> :

>> Path Attribute - MP_REACH_NLRI
>>     Flags: 0x90, Optional, Extended-Length, Non-transitive, Complete
>>     Type Code: MP_REACH_NLRI (14)
>>     Length: 30
>>     Address family identifier (AFI): IPv6 (2)
>>     Subsequent address family identifier (SAFI): Unicast (1)
>>     Next hop network address (16 bytes)
>>     Number of Subnetwork points of attachment (SNPA): 0
>>     Network layer reachability information (9 bytes)
>>         MP Reach NLRI length 184 invalid
>>             [Expert Info (Error/Malformed): MP Reach NLRI length 184 invalid]
>>
>> 0000   90 0e 00 1e 00 02 01 10 20 01 0d b8 00 01 00 00  ........ .......
>> 0010   00 00 00 00 00 00 00 01 00 40 20 01 0d b8 00 53  .........@ ....S
>> 0020   00 00                                            ..
>>
>> Moreover, when routes are withdrawn, the UPDATE message doesn't contain
>> withdrawn routes but come with a MP_UNREACH_NLRI which has the same
>> encoding problem.
>
> In fact, the MP NLRI is correctly encoded. This seems to be a bug in
> Wireshark.

This is https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=14241.

Wireshark has been extended to decode Add-Path ID in IPv6 NLRI but this
ID is present only if the ADD-PATH capability has been negotiated,
something difficult to know for Wireshark as the OPEN message may have
been missed.

Sorry for the noise!
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