Implement RFC6514 MCAST-VPN (incomplete)

[jcpvdm]

https://datatracker.ietf.org/doc/html/rfc6514
This commit starts support for MCAST-VPN NLRI. Route Types added:

• 5 - Source Active A-D route
• 6 - Shared Tree Join route
• 7 - Source Tree Join route

This came out of my need to perform tests for some MCAST-VPN route types. exabgp fit nicely for the task :)
Note there was some reformatting done on unrelated code by black.

[thomas-mangin]

This name may be used when the route is printed and may need to be lower case?

[jcpvdm]

You mean NAME, SHORT_NAME or both? I tried to follow example from other nlri code (like mup and evpn), but didn't notice a pattern regarding lower-case use.

Notice SHORT_NAME is already lower-cased here when printing by _prefix():

exabgp/src/exabgp/bgp/message/update/nlri/mvpn/sharedjoin.py

Lines 51 to 52 in 279a289

	def __str__(self):
	return f'{self._prefix()}:{self.rd._str()}:{str(self.source_as)}:{str(self.source)}:{str(self.group)}'

exabgp/src/exabgp/bgp/message/update/nlri/mvpn/nlri.py

Lines 60 to 61 in 279a289

	def _prefix(self):
	return "mvpn:%s:" % (self.registered_mvpn.get(self.CODE, self).SHORT_NAME.lower())

This is the print output you mean right?

reactor       connected to peer-1 with outgoing-1 10.99.12.6-10.99.12.5
processes     ipv4 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:shared-join::65000:99999:65000:10.99.199.1:239.251.255.228 extended-community target:192.168.94.12:5
processes     ipv4 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:source-join::65000:99999:65000:10.99.12.2:239.251.255.228 extended-community target:192.168.94.12:5
processes     ipv6 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:shared-join::65000:99999:65000:fd00::1:ff0e::1 extended-community target:192.168.94.12:5
processes     ipv6 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:source-join::65000:99999:65000:fd12::2:ff0e::1 extended-community target:192.168.94.12:5
processes     ipv6 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:sourcead::65000:99999:fd12::4:ff0e::1 extended-community target:65000:99999
processes     ipv4 added to neighbor 10.99.12.5 local-ip 10.99.12.6 local-as 65000 peer-as 65000 router-id 32.32.32.32 family-allowed in-open : mvpn:sourcead::65000:99999:10.99.12.4:239.251.255.228 extended-community target:65000:99999

[thomas-mangin]

Does this represent the route in a way which could be parsed by the configuration code?

[jcpvdm]

I didn't get this one. can you share an example?

[thomas-mangin]

Hello @jcpvdm - at first glance, it is an excellent commit. Thank you very much. I have two observations/questions above, which I would appreciate if you could consider.

[ton31337]

From the readability perspective, I'd rather use a normal (full) name multicast-vpn, instead of mcast-vpn.

[jcpvdm]

From the readability perspective, I'd rather use a normal (full) name multicast-vpn, instead of mcast-vpn.

You mean replace all instances of "mcast-vpn" by "multicast-vpn" in the code?

[ton31337]

From the readability perspective, I'd rather use a normal (full) name multicast-vpn, instead of mcast-vpn.

You mean replace all instances of "mcast-vpn" by "multicast-vpn" in the code?

At least in configuration mode :) (seeing as an operator).

[thomas-mangin]

I will need to write some tests and may have to perform a non-backwards compatible change to have what I just asked. I will think about it as I have not enforced this consistently.

Merging. Happy to accept follow up fixes.

[thomas-mangin]

Thank you very much for this work. It is much appreciated. Thank you, @ton31337, too, for the feedback.