fundchannel_start / openchannel_init: add a channel_type parameter to…

… force channel type.

And add request schemas for openchannel_init and fundchannel_start.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Added: JSON-RPC: `fundchannel_start` and `openchannel_init` now take an optional `channel_type` parameter.

contrib/pyln-client/pyln/client/lightning.py

@@ -787,7 +787,7 @@ def fundchannel(self, node_id, amount, feerate=None, announce=True,
         return self.call("fundchannel", payload)
 
     def fundchannel_start(self, node_id, amount, feerate=None, announce=True,
-                          close_to=None, mindepth: Optional[int] = None):
+                          close_to=None, mindepth: Optional[int] = None, channel_type=None):
         """
         Start channel funding with {id} for {amount} satoshis
         with feerate of {feerate} (uses default feerate if unset).
@@ -804,6 +804,7 @@ def fundchannel_start(self, node_id, amount, feerate=None, announce=True,
             "announce": announce,
             "close_to": close_to,
             "mindepth": mindepth,
+            "channel_type": channel_type,
         }
         return self.call("fundchannel_start", payload)
 
@@ -1104,7 +1105,7 @@ def pay(self, bolt11, amount_msat=None, label=None, riskfactor=None,
         }
         return self.call("pay", payload)
 
-    def openchannel_init(self, node_id, channel_amount, psbt, feerate=None, funding_feerate=None, announce=True, close_to=None, request_amt=None, *args, **kwargs):
+    def openchannel_init(self, node_id, channel_amount, psbt, feerate=None, funding_feerate=None, announce=True, close_to=None, request_amt=None, channel_type=None):
         """Initiate an openchannel with a peer """
         payload = {
             "id": node_id,
@@ -1115,6 +1116,7 @@ def openchannel_init(self, node_id, channel_amount, psbt, feerate=None, funding_
             "announce": announce,
             "close_to": close_to,
             "request_amt": request_amt,
+            "channel_type": channel_type,
         }
         return self.call("openchannel_init", payload)
 

doc/lightning-fundchannel_start.7.md

@@ -4,7 +4,7 @@ lightning-fundchannel\_start -- Command for initiating channel establishment for
 SYNOPSIS
 --------
 
-**fundchannel\_start** *id* *amount* [*feerate* *announce* *close\_to* *push\_msat*]
+**fundchannel\_start** *id* *amount* [*feerate*] [*announce*] [*close\_to*] [*push\_msat*] [*channel\_type*]
 
 DESCRIPTION
 -----------
@@ -34,6 +34,21 @@ open. Note that this is a gift to the peer -- these satoshis are
 added to the initial balance of the peer at channel start and are largely
 unrecoverable once pushed.
 
+*channel\_type* *(added v24.02)* is an array of bit numbers, representing the explicit
+channel type to request.  BOLT 2 defines the following value types:
+
+```
+The currently defined basic types are:
+  - no features (no bits set) `[]`
+  - `option_static_remotekey` (`[12]`)
+  - `option_anchor_outputs` and `option_static_remotekey` (`[20, 12]`)
+  - `option_anchors_zero_fee_htlc_tx` and `option_static_remotekey` ([22, 12])
+
+Each basic type has the following variations allowed:
+  - `option_scid_alias` ([46])
+  - `option_zeroconf` ([50])
+```
+
 Note that the funding transaction MUST NOT be broadcast until after
 channel establishment has been successfully completed by running
 `fundchannel_complete`, as the commitment transactions for this channel

doc/lightning-openchannel_init.7.md

@@ -4,7 +4,7 @@ lightning-openchannel\_init -- Command to initiate a channel to a peer
 SYNOPSIS
 --------
 
-**openchannel\_init** *id* *amount* *initalpsbt* [*commitment\_feerate*] [*funding\_feerate*] [*announce*] [*close\_to*] [*request\_amt*] [*compact\_lease*]
+**openchannel\_init** *id* *amount* *initalpsbt* [*commitment\_feerate*] [*funding\_feerate*] [*announce*] [*close\_to*] [*request\_amt*] [*compact\_lease*] [*channel\_type*]
 
 DESCRIPTION
 -----------
@@ -47,6 +47,19 @@ much liquidity into the channel. Must also pass in *compact\_lease*.
 channel lease terms. If the peer's terms don't match this set, we will
 fail to open the channel.
 
+*channel\_type* *(added v24.02)* is an array of bit numbers, representing the explicit
+channel type to request.  BOLT 2 defines the following value types:
+
+The currently defined basic types are:
+  - no features (no bits set) `[]`
+  - `option_static_remotekey` (`[12]`)
+  - `option_anchor_outputs` and `option_static_remotekey` (`[20, 12]`)
+  - `option_anchors_zero_fee_htlc_tx` and `option_static_remotekey` ([22, 12])
+
+Each basic type has the following variations allowed:
+  - `option_scid_alias` ([46])
+  - `option_zeroconf` ([50])
+```
 
 RETURN VALUE
 ------------

doc/schemas/fundchannel_start.request.json

@@ -0,0 +1,43 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "id",
+    "amount"
+  ],
+  "properties": {
+    "id": {
+      "type": "pubkey"
+    },
+    "amount": {
+      "type": "msat"
+    },
+    "feerate": {
+      "type": "feerate"
+    },
+    "announce": {
+      "type": "boolean"
+    },
+    "close_to": {
+      "type": "hex"
+    },
+    "push_msat": {
+      "type": "msat"
+    },
+    "mindepth": {
+      "type": "u32"
+    },
+    "reserve": {
+      "type": "msat"
+    },
+    "channel_type": {
+      "type": "array",
+      "description": "Each bit set in this channel_type",
+      "items": {
+        "type": "u32",
+        "description": "Bit number"
+      }
+    }
+  }
+}

doc/schemas/openchannel_init.request.json

@@ -0,0 +1,47 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "type": "object",
+  "additionalProperties": false,
+  "required": [
+    "id",
+    "amount",
+    "initialpsbt"
+  ],
+  "properties": {
+    "id": {
+      "type": "pubkey"
+    },
+    "amount": {
+      "type": "msat"
+    },
+    "initialpsbt": {
+      "type": "string"
+    },
+    "commitment_feerate": {
+      "type": "feerate"
+    },
+    "funding_feerate": {
+      "type": "feerate"
+    },
+    "announce": {
+      "type": "boolean"
+    },
+    "close_to": {
+      "type": "hex"
+    },
+    "request_amt": {
+      "type": "msat"
+    },
+    "compact_lease": {
+      "type": "hex"
+    },
+    "channel_type": {
+      "type": "array",
+      "description": "Each bit set in this channel_type",
+      "items": {
+        "type": "u32",
+        "description": "Bit number"
+      }
+    }
+  }
+}

lightningd/Makefile

@@ -113,6 +113,7 @@ LIGHTNINGD_COMMON_OBJS :=			\
 	common/invoice_path_id.o		\
 	common/key_derive.o			\
 	common/keyset.o				\
+	common/json_channel_type.o		\
 	common/json_filter.o			\
 	common/json_param.o			\
 	common/json_parse.o			\

lightningd/dual_open_control.c

@@ -9,6 +9,7 @@
 #include <ccan/mem/mem.h>
 #include <ccan/tal/str/str.h>
 #include <common/blockheight_states.h>
+#include <common/json_channel_type.h>
 #include <common/json_command.h>
 #include <common/json_param.h>
 #include <common/psbt_open.h>
@@ -3031,6 +3032,7 @@ static struct command_result *json_openchannel_init(struct command *cmd,
 	struct open_attempt *oa;
 	struct lease_rates *rates;
 	struct command_result *res;
+	struct channel_type *ctype;
 	int fds[2];
 
 	if (!param_check(cmd, buffer, params,
@@ -3043,6 +3045,7 @@ static struct command_result *json_openchannel_init(struct command *cmd,
 			 p_opt("close_to", param_bitcoin_address, &our_upfront_shutdown_script),
 			 p_opt_def("request_amt", param_sat, &request_amt, AMOUNT_SAT(0)),
 			 p_opt("compact_lease", param_lease_hex, &rates),
+			 p_opt("channel_type", param_channel_type, &ctype),
 			 NULL))
 		return command_param_failed();
 
@@ -3103,6 +3106,14 @@ static struct command_result *json_openchannel_init(struct command *cmd,
 				    "by peer");
 	}
 
+	if (ctype &&
+	    !channel_type_accept(tmpctx,
+				 ctype->features,
+				 cmd->ld->our_features)) {
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+				    "channel_type not supported");
+	}
+
 	/* BOLT #2:
 	 *  - if both nodes advertised `option_support_large_channel`:
 	 *    - MAY set `funding_satoshis` greater than or equal to 2^24 satoshi.
@@ -3194,6 +3205,7 @@ static struct command_result *json_openchannel_init(struct command *cmd,
 						NULL : request_amt,
 					   get_block_height(cmd->ld->topology),
 					   false,
+					   ctype,
 					   rates);
 
 	/* Start dualopend! */
@@ -3765,7 +3777,7 @@ static struct command_result *json_queryrates(struct command *cmd,
 						NULL : request_amt,
 					   get_block_height(cmd->ld->topology),
 					   true,
-					   NULL);
+					   NULL, NULL);
 
 	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds) != 0) {
 		return command_fail(cmd, FUND_MAX_EXCEEDED,

lightningd/opening_control.c

@@ -8,6 +8,7 @@
 #include <common/blockheight_states.h>
 #include <common/configdir.h>
 #include <common/fee_states.h>
+#include <common/json_channel_type.h>
 #include <common/json_command.h>
 #include <common/json_param.h>
 #include <common/memleak.h>
@@ -1148,6 +1149,7 @@ static struct command_result *json_fundchannel_start(struct command *cmd,
 	struct amount_msat *push_msat;
 	u32 *upfront_shutdown_script_wallet_index;
 	struct channel_id tmp_channel_id;
+	struct channel_type *ctype;
 
 	fc->cmd = cmd;
 	fc->cancels = tal_arr(fc, struct command *, 0);
@@ -1164,9 +1166,18 @@ static struct command_result *json_fundchannel_start(struct command *cmd,
 			 p_opt("push_msat", param_msat, &push_msat),
 			 p_opt_def("mindepth", param_u32, &mindepth, cmd->ld->config.anchor_confirms),
 			 p_opt("reserve", param_sat, &reserve),
+			 p_opt("channel_type", param_channel_type, &ctype),
 			 NULL))
 		return command_param_failed();
 
+	if (ctype &&
+	    !channel_type_accept(tmpctx,
+				 ctype->features,
+				 cmd->ld->our_features)) {
+		return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+				    "channel_type not supported");
+	}
+
 	if (push_msat && amount_msat_greater_sat(*push_msat, *amount))
 		return command_fail(cmd, FUND_CANNOT_AFFORD,
 				    "Requested to push_msat of %s is greater than "
@@ -1307,7 +1318,8 @@ static struct command_result *json_fundchannel_start(struct command *cmd,
 			unilateral_feerate(cmd->ld->topology, true),
 			&tmp_channel_id,
 			fc->channel_flags,
-			fc->uc->reserve);
+			fc->uc->reserve,
+			ctype);
 
 	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds) != 0) {
 		return command_fail(cmd, FUND_MAX_EXCEEDED,

openingd/dualopend.c

@@ -2952,6 +2952,7 @@ static void opener_start(struct state *state, u8 *msg)
 	struct amount_sat *requested_lease;
 	size_t locktime;
 	u32 nonanchor_feerate, anchor_feerate;
+	struct channel_type *ctype;
 
 	if (!fromwire_dualopend_opener_init(state, msg,
 					    &tx_state->psbt,
@@ -2965,6 +2966,7 @@ static void opener_start(struct state *state, u8 *msg)
 					    &requested_lease,
 					    &tx_state->blockheight,
 					    &dry_run,
+					    &ctype,
 					    &expected_rates))
 		master_badmsg(WIRE_DUALOPEND_OPENER_INIT, msg);
 
@@ -2981,9 +2983,13 @@ static void opener_start(struct state *state, u8 *msg)
 	 *     - SHOULD NOT set it to a type containing a feature which was not
 	 *       negotiated.
 	 */
-	state->channel_type = default_channel_type(state,
+	if (ctype) {
+		state->channel_type = ctype;
+	} else {
+		state->channel_type = default_channel_type(state,
 						   state->our_features,
 						   state->their_features);
+	}
 	open_tlv->channel_type = state->channel_type->features;
 
 	/* Given channel type, which feerate do we use? */

openingd/dualopend_wire.csv

@@ -202,6 +202,7 @@ msgdata,dualopend_opener_init,channel_flags,u8,
 msgdata,dualopend_opener_init,requested_sats,?amount_sat,
 msgdata,dualopend_opener_init,blockheight,u32,
 msgdata,dualopend_opener_init,dry_run,bool,
+msgdata,dualopend_opener_init,channel_type,?channel_type,
 # must go last because embedded tu32
 msgdata,dualopend_opener_init,expected_rates,?lease_rates,