lightningd: add dev-any-channel-type to allow obsolete channel types.

We're about to make static_remotekey compulsory, but we still want to
do tests for pre-existing channels.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

openingd/dualopend.c

@@ -226,6 +226,8 @@ struct state {
 
 	/* Does this negotation require confirmed inputs? */
 	bool require_confirmed_inputs[NUM_SIDES];
+
+	bool dev_accept_any_channel_type;
 };
 
 /* psbt_changeset_get_next - Get next message to send
@@ -2424,11 +2426,18 @@ static void accepter_start(struct state *state, const u8 *oc2_msg)
 					    open_tlv->channel_type,
 					    state->our_features);
 		if (!state->channel_type) {
-			negotiation_failed(state,
-					   "Did not support channel_type %s",
-					   fmt_featurebits(tmpctx,
-							   open_tlv->channel_type));
-			return;
+			if (state->dev_accept_any_channel_type) {
+				status_unusual("dev-any-channel-type: accepting %s",
+					       fmt_featurebits(tmpctx,
+							       open_tlv->channel_type));
+				state->channel_type = channel_type_from(state, open_tlv->channel_type);
+			} else {
+				negotiation_failed(state,
+						   "Did not support channel_type %s",
+						   fmt_featurebits(tmpctx,
+								   open_tlv->channel_type));
+				return;
+			}
 		}
 	} else
 		state->channel_type
@@ -4372,7 +4381,8 @@ int main(int argc, char *argv[])
 				    &state->our_points,
 				    &state->our_funding_pubkey,
 				    &state->minimum_depth,
-				    &state->require_confirmed_inputs[LOCAL])) {
+				    &state->require_confirmed_inputs[LOCAL],
+				    &state->dev_accept_any_channel_type)) {
 		/*~ Initially we're not associated with a channel, but
 		 * handle_peer_gossip_or_error compares this. */
 		memset(&state->channel_id, 0, sizeof(state->channel_id));

openingd/dualopend_wire.csv

@@ -29,6 +29,7 @@ msgdata,dualopend_init,our_funding_pubkey,pubkey,
 # Constraints in case the other end tries to open a channel.
 msgdata,dualopend_init,minimum_depth,u32,
 msgdata,dualopend_init,require_confirmed_inputs,bool,
+msgdata,dualopend_init,dev_accept_any_channel_type,bool,
 
 # master-dualopend: peer has reconnected
 msgtype,dualopend_reinit,7001

openingd/openingd.c

@@ -103,6 +103,8 @@ struct state {
 	struct amount_sat *reserve;
 
 	bool allowdustreserve;
+
+	bool dev_accept_any_channel_type;
 };
 
 /*~ If we can't agree on parameters, we fail to open the channel.
@@ -965,11 +967,18 @@ static u8 *fundee_channel(struct state *state, const u8 *open_channel_msg)
 		state->channel_type = channel_type_accept(
 		    state, open_tlvs->channel_type, state->our_features);
 		if (!state->channel_type) {
-			negotiation_failed(state,
-					   "Did not support channel_type %s",
-					   fmt_featurebits(tmpctx,
-							   open_tlvs->channel_type));
-			return NULL;
+			if (state->dev_accept_any_channel_type) {
+				status_unusual("dev-any-channel-type: accepting %s",
+					       fmt_featurebits(tmpctx,
+							       open_tlvs->channel_type));
+				state->channel_type = channel_type_from(state, open_tlvs->channel_type);
+			} else {
+				negotiation_failed(state,
+						   "Did not support channel_type %s",
+						   fmt_featurebits(tmpctx,
+								   open_tlvs->channel_type));
+				return NULL;
+			}
 		}
 	} else {
 		open_channel_had_channel_type = false;
@@ -1548,7 +1557,8 @@ int main(int argc, char *argv[])
 				    &state->minimum_depth,
 				    &state->min_feerate, &state->max_feerate,
 				    &state->dev_force_tmp_channel_id,
-				    &state->allowdustreserve))
+				    &state->allowdustreserve,
+				    &state->dev_accept_any_channel_type))
 		master_badmsg(WIRE_OPENINGD_INIT, msg);
 
 	/* 3 == peer, 4 = hsmd */

openingd/openingd_wire.csv

@@ -28,6 +28,7 @@ msgdata,openingd_init,dev_temporary_channel_id,?byte,32
 # reserves? This is explicitly required by the spec for safety
 # reasons, but some implementations and users keep asking for it.
 msgdata,openingd_init,allowdustreserve,bool,
+msgdata,openingd_init,dev_accept_any_channel_type,bool,
 
 # Openingd->master: they offered channel, should we continue?
 msgtype,openingd_got_offer,6005