Fix infinite loop when closing a pre-funding channel (channel-establishment, channel-funding)

Host: jbesraa  -  PR author: jbesraa


Creating a channel involves exchanging multiple messages with a connected peer, which does not always end up successfully. Specifically, in the current implementation an infinite loop might occur in the funding step. This bug was resulted from ldk/2077.

ldk/2760 Addresses this bug.

    +-------+                         +-------+
    |       |--(1)- open_channel ---->|       |
    |       |<-(2)- accept_channel ----|       |
    |       |--(3)- funding_created ->|       |
    |       |<-(4)- funding_signed ---|       |
    |       |--(5)- channel_ready --->|       |
    |   A   |<-(6)- channel_ready  ---|   B   |
    +-------+                         +-------+
  • Channel establishment(v1) is the process of creating a channel with a connected peer, as detailed here lightning/bolt02.


  1. Did you review the PR? Concept ACK, approach ACK, tested ACK, or NACK?
  2. In the original code we have a loop inside close_channel_internal, in which scenario it goes indefintly?
  3. Why are we able to drop force_close_channel_with_peer from close_channel_internal, and funding_created msg from SignerResumeUpdate?
  4. What was the reasoning for promoting an OutboundV1Channel to a Channel before receiving funding_signed prior to this PR? Why do we no only do that promotion after receiving funding_signed?