lightningd: add channel_type to openchannel & openchannel2 hooks.

An obvious omission!

Changelog-Added: Plugins: `openchannel` and `openchannel2` hooks now expose the `channel_type` field for the offered channel.
Signed-off-by: Rusty Russell <[email protected]>

Author: rustyrussell

doc/developers-guide/plugin-development/hooks.md

@@ -245,6 +245,7 @@ This hook is called whenever a remote peer tries to fund a channel to us using t
     "to_self_delay": 5,
     "max_accepted_htlcs": 483,
     "channel_flags": 1,
+    "channel_type": {'bits': [12, 22], 'names': ['static_remotekey/even', 'anchors/even']},
     "locktime": 2453,
     "channel_max_msat": 16777215000,
     "requested_lease_msat": 100000000,

lightningd/dual_open_control.c

@@ -274,6 +274,7 @@ struct openchannel2_payload {
 	u32 lease_blockheight_start;
 	u32 node_blockheight;
 	bool req_confirmed_ins_remote;
+	struct channel_type *channel_type;
 
 	struct amount_sat accepter_funding;
 	struct wally_psbt *psbt;
@@ -325,6 +326,7 @@ static void openchannel2_hook_serialize(struct openchannel2_payload *payload,
 	}
 	json_add_bool(stream, "require_confirmed_inputs",
 		      payload->req_confirmed_ins_remote);
+	json_add_channel_type(stream, "channel_type", payload->channel_type);
 	json_object_end(stream);
 }
 
@@ -2098,7 +2100,8 @@ static void accepter_got_offer(struct subd *dualopend,
 					  &payload->shutdown_scriptpubkey,
 					  &payload->requested_lease_amt,
 					  &payload->lease_blockheight_start,
-					  &payload->req_confirmed_ins_remote)) {
+					  &payload->req_confirmed_ins_remote,
+					  &payload->channel_type)) {
 		channel_internal_error(channel, "Bad DUALOPEND_GOT_OFFER: %s",
 				       tal_hex(tmpctx, msg));
 		return;

lightningd/opening_control.c

@@ -647,6 +647,7 @@ struct openchannel_hook_payload {
 	u8 channel_flags;
 	u8 *shutdown_scriptpubkey;
 	const u8 *our_upfront_shutdown_script;
+	struct channel_type *channel_type;
 	char *errmsg;
 };
 
@@ -675,6 +676,7 @@ static void openchannel_hook_serialize(struct openchannel_hook_payload *payload,
 	if (tal_count(payload->shutdown_scriptpubkey) != 0)
 		json_add_hex_talarr(stream, "shutdown_scriptpubkey",
 				    payload->shutdown_scriptpubkey);
+	json_add_channel_type(stream, "channel_type", payload->channel_type);
 	json_object_end(stream); /* .openchannel */
 }
 
@@ -854,7 +856,8 @@ static void opening_got_offer(struct subd *openingd,
 					&payload->to_self_delay,
 					&payload->max_accepted_htlcs,
 					&payload->channel_flags,
-					&payload->shutdown_scriptpubkey)) {
+					&payload->shutdown_scriptpubkey,
+					&payload->channel_type)) {
 		log_broken(openingd->log, "Malformed opening_got_offer %s",
 			   tal_hex(tmpctx, msg));
 		tal_free(openingd);

openingd/dualopend.c

@@ -2528,7 +2528,8 @@ static void accepter_start(struct state *state, const u8 *oc2_msg)
 					 state->upfront_shutdown_script[REMOTE],
 					 state->requested_lease,
 					 tx_state->blockheight,
-					 state->require_confirmed_inputs[REMOTE]);
+					 state->require_confirmed_inputs[REMOTE],
+					 state->channel_type);
 
 	wire_sync_write(REQ_FD, take(msg));
 	msg = wire_sync_read(tmpctx, REQ_FD);

openingd/dualopend_wire.csv

@@ -98,6 +98,7 @@ msgdata,dualopend_got_offer,shutdown_scriptpubkey,u8,shutdown_len
 msgdata,dualopend_got_offer,requested_amt,?amount_sat,
 msgdata,dualopend_got_offer,lease_blockheight_start,u32,
 msgdata,dualopend_got_offer,require_confirmed_inputs,bool,
+msgdata,dualopend_got_offer,ctype,channel_type,
 
 # master->dualopend: reply back with our first funding info/contribs
 msgtype,dualopend_got_offer_reply,7105

openingd/openingd.c

@@ -1009,7 +1009,8 @@ static u8 *fundee_channel(struct state *state, const u8 *open_channel_msg)
 				       state->remoteconf.to_self_delay,
 				       state->remoteconf.max_accepted_htlcs,
 				       channel_flags,
-				       state->upfront_shutdown_script[REMOTE]);
+				       state->upfront_shutdown_script[REMOTE],
+				       state->channel_type);
 	wire_sync_write(REQ_FD, take(msg));
 	msg = wire_sync_read(tmpctx, REQ_FD);
 

openingd/openingd_wire.csv

@@ -44,6 +44,7 @@ msgdata,openingd_got_offer,max_accepted_htlcs,u16,
 msgdata,openingd_got_offer,channel_flags,u8,
 msgdata,openingd_got_offer,shutdown_len,u16,
 msgdata,openingd_got_offer,shutdown_scriptpubkey,u8,shutdown_len
+msgdata,openingd_got_offer,ctype,channel_type,
 
 # master->openingd: optional rejection message
 msgtype,openingd_got_offer_reply,6105

tests/plugins/openchannel_hook_accepter.py

@@ -16,7 +16,7 @@
 plugin = Plugin()
 
 
-def run_openchannel(funding_sats_str, plugin):
+def run_openchannel(funding_sats_str, ctype, plugin):
     # Convert from string to satoshis
     funding_sats = Millisatoshi(funding_sats_str).to_satoshi()
 
@@ -46,19 +46,19 @@ def run_openchannel(funding_sats_str, plugin):
         return {'result': 'continue', 'close_to': 'bc1qlq8srqnz64wgklmqvurv7qnr4rvtq2u96hhfg2'}
 
     # - otherwise: accept and don't include the close_to
-    plugin.log("accept by design")
+    plugin.log(f"accept by design: channel_type {ctype}")
     return {'result': 'continue'}
 
 
 @plugin.hook('openchannel')
 def on_openchannel(openchannel, plugin, **kwargs):
-    return run_openchannel(openchannel['funding_msat'], plugin)
+    return run_openchannel(openchannel['funding_msat'], openchannel['channel_type'], plugin)
 
 
 @plugin.hook('openchannel2')
 def on_openchannel2(openchannel2, plugin, **kwargs):
     """ Support for v2 channel opens """
-    return run_openchannel(openchannel2['their_funding_msat'], plugin)
+    return run_openchannel(openchannel2['their_funding_msat'], openchannel2['channel_type'], plugin)
 
 
 plugin.run()

tests/test_plugin.py

@@ -695,8 +695,10 @@ def test_openchannel_hook(node_factory, bitcoind):
 
     if 'anchors/even' in only_one(l1.rpc.listpeerchannels()['channels'])['channel_type']['names']:
         feerate = 3750
+        expected['channel_type'] = r"{'bits': \[12, 22\], 'names': \['static_remotekey/even', 'anchors/even'\]}"
     else:
         feerate = 7500
+        expected['channel_type'] = r"{'bits': \[12\], 'names': \['static_remotekey/even'\]}"
     if l2.config('experimental-dual-fund'):
         # openchannel2 var checks
         expected.update({
@@ -4328,3 +4330,14 @@ def test_peer_storage(node_factory, bitcoind):
     # This should never happen
     assert not l1.daemon.is_in_log(r'PeerStorageFailed')
     assert not l2.daemon.is_in_log(r'PeerStorageFailed')
+
+
+@pytest.mark.openchannel('v1')
+@pytest.mark.openchannel('v2')
+def test_openchannel_hook_channel_type(node_factory, bitcoind):
+    """openchannel hook should get a channel_type field.
+    """
+    opts = {'plugin': os.path.join(os.getcwd(), 'tests/plugins/openchannel_hook_accepter.py')}
+    l1, l2 = node_factory.line_graph(2, opts=opts)
+
+    l2.daemon.wait_for_log(r"plugin-openchannel_hook_accepter.py: accept by design: channel_type {'bits': \[12, 22\], 'names': \['static_remotekey/even', 'anchors/even'\]}")