df-open: use channel_id for openchannel_update and openchannel_signed

Be as specific as possible is a good rule for things, I think

lightningd/channel.c

@@ -20,6 +20,7 @@
 #include <lightningd/log.h>
 #include <lightningd/notification.h>
 #include <lightningd/opening_control.h>
+#include <lightningd/opening_common.h>
 #include <lightningd/peer_control.h>
 #include <lightningd/subd.h>
 #include <wire/wire_sync.h>
@@ -376,6 +377,35 @@ struct channel *channel_by_dbid(struct lightningd *ld, const u64 dbid)
 	return NULL;
 }
 
+struct channel *channel_by_cid(struct lightningd *ld,
+			       const struct channel_id *cid,
+			       struct uncommitted_channel **uc)
+{
+	struct peer *p;
+	struct channel *channel;
+
+	list_for_each(&ld->peers, p, list) {
+		if (p->uncommitted_channel) {
+			if (channel_id_eq(&p->uncommitted_channel->cid, cid)) {
+				if (uc)
+					*uc = p->uncommitted_channel;
+				return NULL;
+			}
+		}
+		list_for_each(&p->channels, channel, list) {
+			if (channel_id_eq(&channel->cid, cid)) {
+				if (uc)
+					*uc = p->uncommitted_channel;
+				return channel;
+			}
+		}
+	}
+	if (uc)
+		*uc = NULL;
+	return NULL;
+}
+
+
 void channel_set_last_tx(struct channel *channel,
 			 struct bitcoin_tx *tx,
 			 const struct bitcoin_signature *sig,

lightningd/channel.h

@@ -253,6 +253,11 @@ struct channel *channel_by_dbid(struct lightningd *ld, const u64 dbid);
 struct channel *active_channel_by_scid(struct lightningd *ld,
 				       const struct short_channel_id *scid);
 
+/* Get channel by channel_id, optionally returning uncommitted_channel. */
+struct channel *channel_by_cid(struct lightningd *ld,
+			       const struct channel_id *cid,
+			       struct uncommitted_channel **uc);
+
 void channel_set_last_tx(struct channel *channel,
 			 struct bitcoin_tx *tx,
 			 const struct bitcoin_signature *sig,

lightningd/dual_open_control.c

@@ -699,6 +699,7 @@ static void opener_psbt_changed(struct subd *dualopend,
 	json_add_psbt(response, "psbt", psbt);
 	json_add_bool(response, "commitments_secured", false);
 
+	uc->cid = cid;
 	uc->fc->inflight = true;
 	uc->fc->cmd = NULL;
 	was_pending(command_success(cmd, response));
@@ -1009,32 +1010,25 @@ static struct command_result *json_open_channel_signed(struct command *cmd,
 						       const jsmntok_t *params)
 {
 	struct wally_psbt *psbt;
-	struct node_id *id;
-	struct peer *peer;
+	struct channel_id *cid;
 	struct channel *channel;
 	struct bitcoin_txid txid;
 
 	if (!param(cmd, buffer, params,
-		   p_req("id", param_node_id, &id),
+		   p_req("channel_id", param_channel_id, &cid),
 		   p_req("signed_psbt", param_psbt, &psbt),
 		   NULL))
 		return command_param_failed();
 
-	peer = peer_by_id(cmd->ld, id);
-	if (!peer)
-		return command_fail(cmd, FUNDING_UNKNOWN_PEER, "Unknown peer");
-
-	channel = peer_active_channel(peer);
+	channel = channel_by_cid(cmd->ld, cid, NULL);
 	if (!channel)
-		return command_fail(cmd, LIGHTNINGD,
-				    "Peer has no active channel");
-
+		return command_fail(cmd, FUNDING_UNKNOWN_CHANNEL,
+				    "Unknown channel");
 	if (!channel->pps)
 		return command_fail(cmd, LIGHTNINGD,
 				    "Missing per-peer-state for channel, "
 				    "are you in the right state to call "
 				    "this method?");
-
 	if (channel->psbt)
 		return command_fail(cmd, LIGHTNINGD,
 				    "Already have a finalized PSBT for "
@@ -1053,7 +1047,6 @@ static struct command_result *json_open_channel_signed(struct command *cmd,
 				    type_to_string(tmpctx, struct bitcoin_txid,
 						   &txid));
 
-
 	/* Go ahead and try to finalize things, or what we can */
 	psbt_finalize(psbt);
 
@@ -1082,47 +1075,48 @@ static struct command_result *json_open_channel_update(struct command *cmd,
 						       const jsmntok_t *params)
 {
 	struct wally_psbt *psbt;
-	struct node_id *id;
-	struct peer *peer;
+	struct channel_id *cid;
 	struct channel *channel;
+	struct uncommitted_channel *uc;
 	u8 *msg;
 
 	if (!param(cmd, buffer, params,
-		   p_req("id", param_node_id, &id),
+		   p_req("channel_id", param_channel_id, &cid),
 		   p_req("psbt", param_psbt, &psbt),
 		   NULL))
 		return command_param_failed();
 
-	peer = peer_by_id(cmd->ld, id);
-	if (!peer)
-		return command_fail(cmd, FUNDING_UNKNOWN_PEER, "Unknown peer");
-
-	channel = peer_active_channel(peer);
+	/* We expect this to return NULL, as the channel hasn't been
+	 * created yet. Instead, the uncommitted channel is populated */
+	channel = channel_by_cid(cmd->ld, cid, &uc);
 	if (channel)
-		return command_fail(cmd, LIGHTNINGD, "Peer already %s",
+		return command_fail(cmd, LIGHTNINGD, "Channel already %s",
 				    channel_state_name(channel));
 
-	if (!peer->uncommitted_channel)
-		return command_fail(cmd, FUNDING_PEER_NOT_CONNECTED,
-				    "Peer not connected");
+	if (!uc)
+		return command_fail(cmd, FUNDING_UNKNOWN_CHANNEL,
+				    "Unknown channel");
 
-	if (!peer->uncommitted_channel->fc || !peer->uncommitted_channel->fc->inflight)
-		return command_fail(cmd, LIGHTNINGD, "No channel funding in progress");
+	if (!uc->fc || !uc->fc->inflight)
+		return command_fail(cmd, LIGHTNINGD,
+				    "No channel funding in progress");
 
-	if (peer->uncommitted_channel->fc->cmd)
-		return command_fail(cmd, LIGHTNINGD, "Channel funding in progress");
+	if (uc->fc->cmd)
+		return command_fail(cmd, LIGHTNINGD,
+				    "Channel funding in progress");
 
 	/* Add serials to PSBT */
 	psbt_add_serials(psbt, TX_INITIATOR);
 	if (!psbt_has_required_fields(psbt))
 		return command_fail(cmd, FUNDING_PSBT_INVALID,
 				    "PSBT is missing required fields %s",
-				    type_to_string(tmpctx, struct wally_psbt, psbt));
+				    type_to_string(tmpctx, struct wally_psbt,
+						   psbt));
 
-	peer->uncommitted_channel->fc->cmd = cmd;
+	uc->fc->cmd = cmd;
 
 	msg = towire_dual_open_psbt_updated(NULL, psbt);
-	subd_send_msg(peer->uncommitted_channel->open_daemon, take(msg));
+	subd_send_msg(uc->open_daemon, take(msg));
 	return command_still_pending(cmd);
 }
 

lightningd/opening_common.c

@@ -47,6 +47,8 @@ new_uncommitted_channel(struct peer *peer)
 	uc->fc = NULL;
 	uc->our_config.id = 0;
 
+	memset(&uc->cid, 0xFF, sizeof(uc->cid));
+
 	get_channel_basepoints(ld, &uc->peer->id, uc->dbid,
 			       &uc->local_basepoints, &uc->local_funding_pubkey);
 

lightningd/opening_common.h

@@ -4,6 +4,7 @@
 #include <bitcoin/pubkey.h>
 #include <common/amount.h>
 #include <common/channel_config.h>
+#include <common/channel_id.h>
 #include <common/derive_basepoints.h>
 #include <common/status_levels.h>
 
@@ -27,6 +28,9 @@ struct uncommitted_channel {
 	/* Reserved dbid for if we become a real struct channel */
 	u64 dbid;
 
+	/* Channel id, v2 opens only */
+	struct channel_id cid;
+
 	/* For logging */
 	struct log *log;