Added temporary_channel_id to create_channel.

By default, LDK will generate the initial temporary channel ID for you.
However, in certain cases, it's desirable to have a temporary channel ID
specified by the caller in case of any pre-negotiation that needs to
happen between peers prior to the channel open message. For example, LND
has a `FundingShim` API that allows for advanced funding flows based on
the temporary channel ID of the channel.

This patch adds support for optionally specifying the temporary channel
ID of the channel through the `create_channel` API.

fuzz/src/chanmon_consistency.rs

@@ -526,7 +526,7 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out, anchors: bool) {
 				features: $source.init_features(), networks: None, remote_network_address: None
 			}, false).unwrap();
 
-			$source.create_channel($dest.get_our_node_id(), 100_000, 42, 0, None).unwrap();
+			$source.create_channel($dest.get_our_node_id(), 100_000, 42, 0, None, None).unwrap();
 			let open_channel = {
 				let events = $source.get_and_clear_pending_msg_events();
 				assert_eq!(events.len(), 1);

fuzz/src/full_stack.rs

@@ -571,7 +571,7 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
 				let their_key = get_pubkey!();
 				let chan_value = slice_to_be24(get_slice!(3)) as u64;
 				let push_msat_value = slice_to_be24(get_slice!(3)) as u64;
-				if channelmanager.create_channel(their_key, chan_value, push_msat_value, 0, None).is_err() { return; }
+				if channelmanager.create_channel(their_key, chan_value, push_msat_value, 0, None, None).is_err() { return; }
 			},
 			6 => {
 				let mut channels = channelmanager.list_channels();

lightning-background-processor/src/lib.rs

@@ -1241,7 +1241,7 @@ mod tests {
 
 	macro_rules! begin_open_channel {
 		($node_a: expr, $node_b: expr, $channel_value: expr) => {{
-			$node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None).unwrap();
+			$node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None, None).unwrap();
 			$node_b.node.handle_open_channel(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendOpenChannel, $node_b.node.get_our_node_id()));
 			$node_a.node.handle_accept_channel(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendAcceptChannel, $node_a.node.get_our_node_id()));
 		}}

lightning-invoice/src/utils.rs

@@ -1141,7 +1141,7 @@ mod test {
 		// is never handled, the `channel.counterparty.forwarding_info` is never assigned.
 		let mut private_chan_cfg = UserConfig::default();
 		private_chan_cfg.channel_handshake_config.announced_channel = false;
-		let temporary_channel_id = nodes[2].node.create_channel(nodes[0].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
+		let temporary_channel_id = nodes[2].node.create_channel(nodes[0].node.get_our_node_id(), 1_000_000, 500_000_000, 42, None, Some(private_chan_cfg)).unwrap();
 		let open_channel = get_event_msg!(nodes[2], MessageSendEvent::SendOpenChannel, nodes[0].node.get_our_node_id());
 		nodes[0].node.handle_open_channel(&nodes[2].node.get_our_node_id(), &open_channel);
 		let accept_channel = get_event_msg!(nodes[0], MessageSendEvent::SendAcceptChannel, nodes[2].node.get_our_node_id());
@@ -1547,7 +1547,7 @@ mod test {
 		// is never handled, the `channel.counterparty.forwarding_info` is never assigned.
 		let mut private_chan_cfg = UserConfig::default();
 		private_chan_cfg.channel_handshake_config.announced_channel = false;
-		let temporary_channel_id = nodes[1].node.create_channel(nodes[3].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
+		let temporary_channel_id = nodes[1].node.create_channel(nodes[3].node.get_our_node_id(), 1_000_000, 500_000_000, 42, None, Some(private_chan_cfg)).unwrap();
 		let open_channel = get_event_msg!(nodes[1], MessageSendEvent::SendOpenChannel, nodes[3].node.get_our_node_id());
 		nodes[3].node.handle_open_channel(&nodes[1].node.get_our_node_id(), &open_channel);
 		let accept_channel = get_event_msg!(nodes[3], MessageSendEvent::SendAcceptChannel, nodes[1].node.get_our_node_id());

lightning/src/ln/async_signer_tests.rs

@@ -23,7 +23,7 @@ fn test_async_commitment_signature_for_funding_created() {
 	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 	let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None, None).unwrap();
 
 	// nodes[0] --- open_channel --> nodes[1]
 	let mut open_chan_msg = get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id());
@@ -74,7 +74,7 @@ fn test_async_commitment_signature_for_funding_signed() {
 	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 	let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None, None).unwrap();
 
 	// nodes[0] --- open_channel --> nodes[1]
 	let mut open_chan_msg = get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id());
@@ -177,7 +177,7 @@ fn test_async_commitment_signature_for_funding_signed_0conf() {
 	let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
 	// nodes[0] --- open_channel --> nodes[1]
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 42, None, None).unwrap();
 	let open_channel = get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id());
 
 	nodes[1].node.handle_open_channel(&nodes[0].node.get_our_node_id(), &open_channel);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -1850,7 +1850,7 @@ fn do_during_funding_monitor_fail(confirm_a_first: bool, restore_b_before_conf:
 	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None, None).unwrap();
 	nodes[1].node.handle_open_channel(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id()));
 	nodes[0].node.handle_accept_channel(&nodes[1].node.get_our_node_id(), &get_event_msg!(nodes[1], MessageSendEvent::SendAcceptChannel, nodes[0].node.get_our_node_id()));
 
@@ -2768,7 +2768,7 @@ fn do_test_outbound_reload_without_init_mon(use_0conf: bool) {
 
 	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None, None).unwrap();
 	nodes[1].node.handle_open_channel(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id()));
 
 	let events = nodes[1].node.get_and_clear_pending_events();
@@ -2859,7 +2859,7 @@ fn do_test_inbound_reload_without_init_mon(use_0conf: bool, lock_commitment: boo
 
 	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
-	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None).unwrap();
+	nodes[0].node.create_channel(nodes[1].node.get_our_node_id(), 100000, 10001, 43, None, None).unwrap();
 	nodes[1].node.handle_open_channel(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id()));
 
 	let events = nodes[1].node.get_and_clear_pending_events();