lnd sends announcement_signatures before reestablish_channel

[rustyrussell]

Background

You're supposed to send reestablish first, and also wait for the reply.

ElementsProject/lightning#2559

Your environment

The source was Pierre Rochard's node, which he tells me is 0.5.2-99-beta commit=queue/v1.0.1-109-g9f6a1403e9773ba97ec0e9fdee3b654789970d3a

Steps to reproduce

Take your c-lightning node (minus above fix) up and down several times while lnd connects with a relatively fresh channel.

Expected behaviour

Delay other channel msgs until REESTABLISH sent and received.

Actual behaviour

Rusty writes nasty code in c-lightning to defer unexpected packets. We had an earlier issue with funding_locked, but I had special cased that. Now I just defer all weird stuff.

[cfromknecht]

Hmm, BOLT 2 section on Message Retransmission says that BOLT 7 messages are not required to wait for ChannelReestablish:

Note that messages described in BOLT #7 are independent of particular channels; their transmission requirements are covered there, and besides being transmitted after init (as all messages are), they are independent of requirements here.

and BOLT 7 does not include anything about ChannelReestablish in the retransmission requirements for AnnouncementSignatures, AFAICT.

I assume then, that this the issue in regards to delaying BOLT 7 messages only if:

1. They pertain to a channel with the current peer, and
2. We have not sent ChannelReestablish for that channel?

If I understand correctly, what is the benefit of being able to send info about everyone else's channels immediately, but withhold relevant gossip info from your channel partner until after ChannelReestablish?

[Roasbeef]

Closing as a duplicate of #2555.