common/blindedpath: generalize construction routines.

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

common/blindedpath.c

@@ -256,8 +256,12 @@ u8 *create_enctlv(const tal_t *ctx,
 		  const struct privkey *blinding,
 		  const struct pubkey *node,
 		  const struct pubkey *next_node,
+		  const struct short_channel_id *next_scid,
 		  size_t padlen,
 		  const struct pubkey *next_blinding_override,
+		  const struct tlv_encrypted_data_tlv_payment_relay *payment_relay TAKES,
+		  const struct tlv_encrypted_data_tlv_payment_constraints *payment_constraints TAKES,
+		  const u8 *allowed_features TAKES,
 		  struct privkey *next_blinding,
 		  struct pubkey *node_alias)
 {
@@ -266,6 +270,11 @@ u8 *create_enctlv(const tal_t *ctx,
 		encmsg->padding = tal_arrz(encmsg, u8, padlen);
 	encmsg->next_node_id = cast_const(struct pubkey *, next_node);
 	encmsg->next_blinding_override = cast_const(struct pubkey *, next_blinding_override);
+	encmsg->payment_relay = tal_dup_or_null(encmsg, struct tlv_encrypted_data_tlv_payment_relay,
+						payment_relay);
+	encmsg->payment_constraints = tal_dup_or_null(encmsg, struct tlv_encrypted_data_tlv_payment_constraints,
+						      payment_constraints);
+	encmsg->allowed_features = tal_dup_talarr(encmsg, u8, allowed_features);
 
 	return enctlv_from_encmsg(ctx, blinding, node, encmsg,
 				  next_blinding, node_alias);
@@ -276,6 +285,7 @@ u8 *create_final_enctlv(const tal_t *ctx,
 			const struct pubkey *final_node,
 			size_t padlen,
 			const struct secret *path_id,
+			const u8 *allowed_features TAKES,
 			struct pubkey *node_alias)
 {
 	struct tlv_encrypted_data_tlv *encmsg = tlv_encrypted_data_tlv_new(tmpctx);
@@ -285,6 +295,7 @@ u8 *create_final_enctlv(const tal_t *ctx,
 		encmsg->padding = tal_arrz(encmsg, u8, padlen);
 	if (path_id)
 		encmsg->path_id = (u8 *)tal_dup(encmsg, struct secret, path_id);
+	encmsg->allowed_features = tal_dup_talarr(encmsg, u8, allowed_features);
 
 	return enctlv_from_encmsg(ctx, blinding, final_node, encmsg,
 				  &unused_next_blinding, node_alias);

common/blindedpath.h

@@ -9,6 +9,9 @@ struct route_info;
 struct pubkey;
 struct privkey;
 struct secret;
+struct short_channel_id;
+struct tlv_encrypted_data_tlv_payment_constraints;
+struct tlv_encrypted_data_tlv_payment_relay;
 
 /**
  * create_enctlv - Encrypt an encmsg to form an enctlv.
@@ -16,22 +19,31 @@ struct secret;
  * @blinding: e(i), the blinding secret
  * @node: the pubkey of the node to encrypt for
  * @next_node: the pubkey of the next node, to place in enctlv
+ * @next_scid: the short_channel_id to the next node, to place in enctlv
  * @padlen: if non-zero, the bytes of padding to add (also adds 2 byte padding hdr)
  * @next_blinding_override: the optional blinding point to place in enctlv
+ * @payment_relay: optional payment_relay tlv
+ * @payment_constraints: optional payment_constraints tlv
+ * @allowed_features: optional allowed_features array
  * @next_blinding: (out) e(i+1), the next blinding secret.
  * @node_alias: (out) the blinded pubkey of the node to tell the recipient.
  *
+ * Exactly one of next_node and next_scid must be non-NULL.
  * Returns the enctlv blob, or NULL if the secret is invalid.
  */
 u8 *create_enctlv(const tal_t *ctx,
 		  const struct privkey *blinding,
 		  const struct pubkey *node,
 		  const struct pubkey *next_node,
+		  const struct short_channel_id *next_scid,
 		  size_t padlen,
 		  const struct pubkey *next_blinding_override,
+		  const struct tlv_encrypted_data_tlv_payment_relay *payment_relay TAKES,
+		  const struct tlv_encrypted_data_tlv_payment_constraints *payment_constraints TAKES,
+		  const u8 *allowed_features TAKES,
 		  struct privkey *next_blinding,
 		  struct pubkey *node_alias)
-	NON_NULL_ARGS(2, 3, 4, 7, 8);
+	NON_NULL_ARGS(2, 3, 11, 12);
 
 /**
  * create_final_enctlv - Encrypt an encmsg to form the final enctlv.
@@ -39,6 +51,7 @@ u8 *create_enctlv(const tal_t *ctx,
  * @blinding: e(i), the blinding secret
  * @final_node: the pubkey of the node to encrypt for
  * @padlen: if non-zero, the bytes of padding to add (also adds 2 byte padding hdr)
+ * @allowed_features: optional allowed_features array
  * @path_id: secret to include in enctlv, if not NULL.
  * @node_alias: (out) the blinded pubkey of the node to tell the recipient.
  *
@@ -49,8 +62,9 @@ u8 *create_final_enctlv(const tal_t *ctx,
 			const struct pubkey *final_node,
 			size_t padlen,
 			const struct secret *path_id,
+			const u8 *allowed_features TAKES,
 			struct pubkey *node_alias)
-	NON_NULL_ARGS(2, 3, 6);
+	NON_NULL_ARGS(2, 3, 7);
 
 /**
  * unblind_onion - tweak onion epheremeral key so we can decode it with ours.

common/test/run-blindedpath_enctlv.c

@@ -171,8 +171,8 @@ int main(int argc, char *argv[])
 	       "\t},\n",
 	       type_to_string(tmpctx, struct pubkey, &bob_id));
 
-	enctlv = create_enctlv(tmpctx, &blinding, &alice_id, &bob_id,
+	enctlv = create_enctlv(tmpctx, &blinding, &alice_id, &bob_id, NULL,
-			       0, NULL, &blinding, &alias);
+			       0, NULL, NULL, NULL, NULL, &blinding, &alias);
 	printf("\t\"encrypted_recipient_data_hex\": \"%s\"\n"
 	       "},\n",
 	       tal_hex(tmpctx, enctlv));
@@ -201,8 +201,9 @@ int main(int argc, char *argv[])
 	       type_to_string(tmpctx, struct pubkey, &carol_id),
 	       type_to_string(tmpctx, struct privkey, &override_blinding));
 
-	enctlv = create_enctlv(tmpctx, &blinding, &bob_id, &carol_id,
+	enctlv = create_enctlv(tmpctx, &blinding, &bob_id, &carol_id, NULL,
-			       0, &override_blinding_pub, &blinding, &alias);
+			       0, &override_blinding_pub, NULL, NULL, NULL,
+			       &blinding, &alias);
 	printf("\t\"encrypted_recipient_data_hex\": \"%s\"\n"
 	       "},\n",
 	       tal_hex(tmpctx, enctlv));
@@ -230,8 +231,8 @@ int main(int argc, char *argv[])
 	       type_to_string(tmpctx, struct pubkey, &dave_id),
 	       tal_hex(tmpctx, tal_arrz(tmpctx, u8, 35)));
 
-	enctlv = create_enctlv(tmpctx, &blinding, &carol_id, &dave_id,
+	enctlv = create_enctlv(tmpctx, &blinding, &carol_id, &dave_id, NULL,
-			       35, NULL, &blinding, &alias);
+			       35, NULL, NULL, NULL, NULL, &blinding, &alias);
 	printf("\t\"encrypted_recipient_data_hex\": \"%s\"\n"
 	       "},\n",
 	       tal_hex(tmpctx, enctlv));
@@ -256,7 +257,7 @@ int main(int argc, char *argv[])
 	       type_to_string(tmpctx, struct secret, &self_id));
 
 	enctlv = create_final_enctlv(tmpctx, &blinding, &dave_id,
-				     0, &self_id, &alias);
+				     0, &self_id, NULL, &alias);
 
 	printf("\t\"encrypted_recipient_data_hex\": \"%s\"\n",
 	       tal_hex(tmpctx, enctlv));

common/test/run-blindedpath_onion.c

@@ -170,8 +170,9 @@ int main(int argc, char *argv[])
 	pubkey_from_privkey(&blinding[ALICE], &blinding_pub[ALICE]);
 
 	enctlv[ALICE] = create_enctlv(tmpctx, &blinding[ALICE],
-				      &id[ALICE], &id[BOB],
+				      &id[ALICE], &id[BOB], NULL,
-				      0, NULL, &blinding[BOB], &alias[ALICE]);
+				      0, NULL, NULL, NULL, NULL,
+				      &blinding[BOB], &alias[ALICE]);
 
 	pubkey_from_privkey(&blinding[BOB], &blinding_pub[BOB]);
 
@@ -179,8 +180,8 @@ int main(int argc, char *argv[])
 	memset(&override_blinding, 7, sizeof(override_blinding));
 	pubkey_from_privkey(&override_blinding, &override_blinding_pub);
 	enctlv[BOB] = create_enctlv(tmpctx, &blinding[BOB],
-				    &id[BOB], &id[CAROL],
+				    &id[BOB], &id[CAROL], NULL,
-				    0, &override_blinding_pub,
+				    0, &override_blinding_pub, NULL, NULL, NULL,
 				    &blinding[CAROL], &alias[BOB]);
 
 	/* That replaced the blinding */
@@ -188,14 +189,15 @@ int main(int argc, char *argv[])
 	blinding_pub[CAROL] = override_blinding_pub;
 
 	enctlv[CAROL] = create_enctlv(tmpctx, &blinding[CAROL],
-				      &id[CAROL], &id[DAVE],
+				      &id[CAROL], &id[DAVE], NULL,
-				      35, NULL, &blinding[DAVE], &alias[CAROL]);
+				      35, NULL, NULL, NULL, NULL,
+				      &blinding[DAVE], &alias[CAROL]);
 
 	for (size_t i = 0; i < sizeof(self_id); i++)
 		self_id.data[i] = i+1;
 
 	enctlv[DAVE] = create_final_enctlv(tmpctx, &blinding[DAVE], &id[DAVE],
-					   0, &self_id, &alias[DAVE]);
+					   0, &self_id, NULL, &alias[DAVE]);
 	pubkey_from_privkey(&blinding[DAVE], &blinding_pub[DAVE]);
 
 	/* Create an onion which encodes this. */

lightningd/onion_message.c

@@ -336,10 +336,10 @@ static struct command_result *json_blindedpath(struct command *cmd,
 		path[i]->encrypted_recipient_data = create_enctlv(path[i],
 						     &blinding_iter,
 						     &ids[i],
-						     &ids[i+1],
+						     &ids[i+1], NULL,
 						     /* FIXME: Pad? */
 						     0,
-						     NULL,
+						     NULL, NULL, NULL, NULL,
 						     &blinding_iter,
 						     &path[i]->node_id);
 	}
@@ -352,6 +352,7 @@ static struct command_result *json_blindedpath(struct command *cmd,
 							 /* FIXME: Pad? */
 							 0,
 							 &cmd->ld->onion_reply_secret,
+							 NULL,
 							 &path[nhops-1]->node_id);
 
 	response = json_stream_success(cmd);

plugins/fetchinvoice.c

@@ -638,9 +638,10 @@ send_modern_message(struct command *cmd,
 						    &blinding_iter,
 						    &sent->path[i],
 						    &sent->path[i+1],
+						    NULL,
 						    /* FIXME: Pad? */
 						    0,
-						    NULL,
+						    NULL, NULL, NULL, NULL,
 						    &blinding_iter,
 						    &node_alias[i]);
 	}
@@ -650,7 +651,7 @@ send_modern_message(struct command *cmd,
 	/* We don't include enctlv in final, but it gives us final alias */
 	if (!create_final_enctlv(tmpctx, &blinding_iter, &sent->path[nhops-1],
 				 /* FIXME: Pad? */ 0,
-				 NULL,
+				 NULL, NULL,
 				 &node_alias[nhops-1])) {
 		/* Should not happen! */
 		return command_fail(cmd, LIGHTNINGD,