From 9e839b177c236988e482de01416d445340d2e1c1 Mon Sep 17 00:00:00 2001
From: niftynei <niftynei@gmail.com>
Date: Thu, 10 Jun 2021 15:30:19 -0500
Subject: [PATCH] gossipd: turn off lease offers if the rates are empty

If received lease rates are empty (all zeroes), turn them off
---
 common/Makefile      |  1 +
 common/lease_rates.c | 17 +++++++++++++++++
 common/lease_rates.h |  9 +++++++++
 gossipd/Makefile     |  1 +
 gossipd/gossipd.c    |  8 ++++++--
 5 files changed, 34 insertions(+), 2 deletions(-)
 create mode 100644 common/lease_rates.c
 create mode 100644 common/lease_rates.h

diff --git a/common/Makefile b/common/Makefile
index 21a22cd94..0ca8359fb 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -53,6 +53,7 @@ COMMON_SRC_NOGEN :=				\
 	common/key_derive.c			\
 	common/keyset.c				\
 	common/gossmap.c			\
+	common/lease_rates.c			\
 	common/memleak.c			\
 	common/msg_queue.c			\
 	common/node_id.c			\
diff --git a/common/lease_rates.c b/common/lease_rates.c
new file mode 100644
index 000000000..cf0b40244
--- /dev/null
+++ b/common/lease_rates.c
@@ -0,0 +1,17 @@
+#include "config.h"
+#include <ccan/ccan/mem/mem.h>
+#include <common/lease_rates.h>
+#include <wire/peer_wire.h>
+
+bool lease_rates_empty(struct lease_rates *rates)
+{
+	if (!rates)
+		return true;
+
+	/* FIXME: why can't i do memeqzero? */
+	return rates->funding_weight == 0
+		&& rates->channel_fee_max_base_msat == 0
+		&& rates->channel_fee_max_proportional_thousandths == 0
+		&& rates->lease_fee_base_sat == 0
+		&& rates->lease_fee_basis == 0;
+}
diff --git a/common/lease_rates.h b/common/lease_rates.h
new file mode 100644
index 000000000..dd10e79fb
--- /dev/null
+++ b/common/lease_rates.h
@@ -0,0 +1,9 @@
+#ifndef LIGHTNING_COMMON_LEASE_RATES_H
+#define LIGHTNING_COMMON_LEASE_RATES_H
+#include "config.h"
+#include <stdbool.h>
+
+struct lease_rates;
+
+bool lease_rates_empty(struct lease_rates *rates);
+#endif /* LIGHTNING_COMMON_LEASE_RATES_H */
diff --git a/gossipd/Makefile b/gossipd/Makefile
index 7d4f7d70a..510ebccf9 100644
--- a/gossipd/Makefile
+++ b/gossipd/Makefile
@@ -48,6 +48,7 @@ GOSSIPD_COMMON_OBJS :=				\
 	common/status_wiregen.o			\
 	common/gossip_rcvd_filter.o		\
 	common/key_derive.o			\
+	common/lease_rates.o			\
 	common/memleak.o			\
 	common/msg_queue.o			\
 	common/node_id.o			\
diff --git a/gossipd/gossipd.c b/gossipd/gossipd.c
index 722d0db8e..2e09b7e6c 100644
--- a/gossipd/gossipd.c
+++ b/gossipd/gossipd.c
@@ -32,6 +32,7 @@
 #include <common/daemon_conn.h>
 #include <common/ecdh_hsmd.h>
 #include <common/features.h>
+#include <common/lease_rates.h>
 #include <common/memleak.h>
 #include <common/ping.h>
 #include <common/pseudorand.h>
@@ -1418,8 +1419,11 @@ static struct io_plan *handle_new_lease_rates(struct io_conn *conn,
 	if (!fromwire_gossipd_new_lease_rates(msg, rates))
 		master_badmsg(WIRE_GOSSIPD_NEW_LEASE_RATES, msg);
 
-	tal_free(daemon->rates);
-	daemon->rates = rates;
+	daemon->rates = tal_free(daemon->rates);
+	if (!lease_rates_empty(rates))
+		daemon->rates = rates;
+	else
+		tal_free(rates);
 
 	/* Send the update over to the peer */
 	maybe_send_own_node_announce(daemon, false);