df: use dev-env flagged upfront shutdown script

This lets the test_option_upfront_shutdown_script test pass

openingd/common.c

@@ -1,6 +1,7 @@
 #include <ccan/ccan/tal/str/str.h>
 #include <common/amount.h>
 #include <common/channel_config.h>
+#include <common/features.h>
 #include <common/initial_commit_tx.h>
 #include <common/type_to_string.h>
 #include <openingd/common.h>
@@ -194,3 +195,30 @@ bool check_config_bounds(const tal_t *ctx,
 
 	return true;
 }
+
+u8 *no_upfront_shutdown_script(const tal_t *ctx,
+			       struct feature_set *our_features,
+			       const u8 *their_features)
+{
+#if DEVELOPER
+	/* This is a hack, for feature testing */
+	const char *e = getenv("DEV_OPENINGD_UPFRONT_SHUTDOWN_SCRIPT");
+	if (e)
+		return tal_hexdata(ctx, e, strlen(e));
+#endif
+
+	/* BOLT #2:
+	 *
+	 * - if both nodes advertised the `option_upfront_shutdown_script`
+	 *   feature:
+	 *   - MUST include `upfront_shutdown_script` with either a valid
+	 *     `shutdown_scriptpubkey` as required by `shutdown`
+	 *     `scriptpubkey`, or a zero-length `shutdown_scriptpubkey`
+	 *     (ie. `0x0000`).
+	 */
+	if (feature_negotiated(our_features, their_features,
+			       OPT_UPFRONT_SHUTDOWN_SCRIPT))
+		return tal_arr(ctx, u8, 0);
+
+	return NULL;
+}

openingd/common.h

@@ -18,4 +18,7 @@ bool check_config_bounds(const tal_t *ctx,
 			 bool option_anchor_outputs,
 			 char **err_reason);
 
+u8 *no_upfront_shutdown_script(const tal_t *ctx,
+			       struct feature_set *our_features,
+			       const u8 *their_features);
 #endif /* LIGHTNING_OPENINGD_COMMON_H */

openingd/dualopend.c

@@ -1573,12 +1573,20 @@ static void accepter_start(struct state *state, const u8 *oc2_msg)
 
 	/* If we have an upfront shutdown script, send it to our peer */
 	struct tlv_accept_tlvs *a_tlv = tlv_accept_tlvs_new(state);
-	if (state->upfront_shutdown_script[LOCAL]) {
-		a_tlv->option_upfront_shutdown_script = tal(a_tlv,
-				struct tlv_accept_tlvs_option_upfront_shutdown_script);
-		a_tlv->option_upfront_shutdown_script->shutdown_scriptpubkey =
-			tal_dup_arr(a_tlv, u8, state->upfront_shutdown_script[LOCAL],
-				    tal_count(state->upfront_shutdown_script[LOCAL]), 0);
+	if (!state->upfront_shutdown_script[LOCAL])
+		state->upfront_shutdown_script[LOCAL]
+			= no_upfront_shutdown_script(state,
+						     state->our_features,
+						     state->their_features);
+
+	if (tal_bytelen(state->upfront_shutdown_script[LOCAL])) {
+		a_tlv->option_upfront_shutdown_script
+			= tal(a_tlv, struct tlv_accept_tlvs_option_upfront_shutdown_script);
+		a_tlv->option_upfront_shutdown_script->shutdown_scriptpubkey
+			= tal_dup_arr(a_tlv, u8,
+				      state->upfront_shutdown_script[LOCAL],
+				      tal_count(state->upfront_shutdown_script[LOCAL]),
+				      0);
 	}
 
 	msg = towire_accept_channel2(tmpctx, &state->channel_id,
@@ -1868,7 +1876,13 @@ static void opener_start(struct state *state, u8 *msg)
 	}
 	feerate_best = state->feerate_per_kw_funding;
 
-	if (state->upfront_shutdown_script[LOCAL]) {
+	if (!state->upfront_shutdown_script[LOCAL])
+		state->upfront_shutdown_script[LOCAL]
+			= no_upfront_shutdown_script(state,
+						     state->our_features,
+						     state->their_features);
+
+	if (tal_bytelen(state->upfront_shutdown_script[LOCAL])) {
 		open_tlv->option_upfront_shutdown_script =
 			tal(open_tlv,
 			    struct tlv_opening_tlvs_option_upfront_shutdown_script);

openingd/openingd.c

@@ -119,31 +119,6 @@ struct state {
 	struct feature_set *our_features;
 };
 
-static u8 *no_upfront_shutdown_script(const tal_t *ctx, struct state *state)
-{
-#if DEVELOPER
-	/* This is a hack, for feature testing */
-	const char *e = getenv("DEV_OPENINGD_UPFRONT_SHUTDOWN_SCRIPT");
-	if (e)
-		return tal_hexdata(ctx, e, strlen(e));
-#endif
-
-	/* BOLT #2:
-	 *
-	 * - if both nodes advertised the `option_upfront_shutdown_script`
-	 *   feature:
-	 *   - MUST include `upfront_shutdown_script` with either a valid
-	 *     `shutdown_scriptpubkey` as required by `shutdown`
-	 *     `scriptpubkey`, or a zero-length `shutdown_scriptpubkey`
-	 *     (ie. `0x0000`).
-	 */
-	if (feature_negotiated(state->our_features, state->their_features,
-			       OPT_UPFRONT_SHUTDOWN_SCRIPT))
-		return tal_arr(ctx, u8, 0);
-
-	return NULL;
-}
-
 /*~ If we can't agree on parameters, we fail to open the channel.  If we're
  * the opener, we need to tell lightningd, otherwise it never really notices. */
 static void negotiation_aborted(struct state *state, bool am_opener,
@@ -371,7 +346,10 @@ static u8 *funder_channel_start(struct state *state, u8 channel_flags)
 		return NULL;
 
 	if (!state->upfront_shutdown_script[LOCAL])
-		state->upfront_shutdown_script[LOCAL] = no_upfront_shutdown_script(state, state);
+		state->upfront_shutdown_script[LOCAL]
+			= no_upfront_shutdown_script(state,
+						     state->our_features,
+						     state->their_features);
 
 	open_tlvs = tlv_open_channel_tlvs_new(tmpctx);
 	open_tlvs->upfront_shutdown_script
@@ -955,7 +933,10 @@ static u8 *fundee_channel(struct state *state, const u8 *open_channel_msg)
 	}
 
 	if (!state->upfront_shutdown_script[LOCAL])
-		state->upfront_shutdown_script[LOCAL] = no_upfront_shutdown_script(state, state);
+		state->upfront_shutdown_script[LOCAL]
+			= no_upfront_shutdown_script(state,
+						     state->our_features,
+						     state->their_features);
 
 	/* OK, we accept! */
 	accept_tlvs = tlv_accept_channel_tlvs_new(tmpctx);