Merge pull request #8308 from ziggie1984/new_min_cltv_default

zpay32: Change min_final_cltv_expiry_delta.

docs/release-notes/release-notes-0.18.0.md

@@ -170,6 +170,13 @@
   be switched off using the new `protocol.no-timestamp-query-option` config 
   option. 
 
+* [Update min_final_cltv_expiry_delta](https://github.com/lightningnetwork/lnd/pull/8308).
+  This only effects external invoices which do not supply the 
+  min_final_cltv_expiry parameter. LND has NOT allowed the creation of invoices
+  with a lower min_final_cltv_expiry_delta value than 18 blocks since
+  LND 0.11.0.
+
+
 ## Testing
 
 * Added fuzz tests for [onion

zpay32/hophint.go

@@ -6,7 +6,10 @@ const (
 	// DefaultAssumedFinalCLTVDelta is the default value to be used as the
 	// final CLTV delta for a route if one is unspecified in the payment
 	// request.
-	DefaultAssumedFinalCLTVDelta = 9
+	// We adhere to the recommendation in BOLT 02 for terminal payments.
+	// See also:
+	// https://github.com/lightning/bolts/blob/master/02-peer-protocol.md
+	DefaultAssumedFinalCLTVDelta = 18
 )
 
 // HopHint is a routing hint that contains the minimum information of a channel