Matt Corallo 9cc6e08965 Block monitor updates to ensure preimages are in each MPP part ... If we claim an MPP payment and only persist some of the `ChannelMonitorUpdate`s which include the preimage prior to shutting down, we may be in a state where some of our `ChannelMonitor`s have the preimage for a payment while others do not. This, it turns out, is actually mostly safe - on startup `ChanelManager` will detect there's a payment it has as unclaimed but there's a corresponding payment preimage in a `ChannelMonitor` and go claim the other MPP parts. This works so long as the `ChannelManager` has been persisted after the payment has been received but prior to the `PaymentClaimable` event being processed (and the claim itself occurring). This is not always true and certainly not required on our API, but our `lightning-background-processor` today does persist prior to event handling so is generally true subject to some race conditions. In order to address this we need to use copy payment preimages across channels irrespective of the `ChannelManager`'s payment state, but this introduces another wrinkle - if one channel makes substantial progress while other channel(s) are still waiting to get the payment preimage in `ChannelMonitor`(s) while the `ChannelManager` hasn't been persisted after the payment was received, we may end up without the preimage on disk. Here, we address this issue by using the new `RAAMonitorUpdateBlockingAction` variant for this specific case. We block persistence of an RAA `ChannelMonitorUpdate` which may remove the preimage from disk until all channels have had the preimage added to their `ChannelMonitor`. We do this only in-memory (and not on disk) as we can recreate this blocker during the startup re-claim logic. This will enable us to claim MPP parts without using the `ChannelManager`'s payment state in later work.		2024-07-08 19:07:11 +00:00
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src	Block monitor updates to ensure preimages are in each MPP part	2024-07-08 19:07:11 +00:00
Cargo.toml	Upgrade rust-bitcoin to 0.31	2024-05-30 18:35:29 +08:00