From 59a7a9d308dbcaa191c8befb1a9d63d99644e45c Mon Sep 17 00:00:00 2001
From: Joost Jager <joost.jager@gmail.com>
Date: Fri, 10 Jan 2020 21:35:10 +0100
Subject: [PATCH] invoices: pre-check key send expiry

---
 invoices/invoiceregistry.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/invoices/invoiceregistry.go b/invoices/invoiceregistry.go
index c3354c97..238e3bb7 100644
--- a/invoices/invoiceregistry.go
+++ b/invoices/invoiceregistry.go
@@ -736,6 +736,12 @@ func (i *InvoiceRegistry) processKeySend(ctx invoiceUpdateCtx,
 	// Use the minimum block delta that we require for settling htlcs.
 	finalCltvDelta := i.cfg.FinalCltvRejectDelta
 
+	// Pre-check expiry here to prevent inserting an invoice that will not
+	// be settled.
+	if ctx.expiry < uint32(ctx.currentHeight+finalCltvDelta) {
+		return errors.New("final expiry too soon")
+	}
+
 	// Create placeholder invoice.
 	invoice := &channeldb.Invoice{
 		CreationDate: i.cfg.Clock.Now(),