Conditionally advertise onion msgs in node features in ChannelManager

lightning/src/ln/channelmanager.rs

@@ -2973,8 +2973,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 		// addresses be sorted for future compatibility.
 		addresses.sort_by_key(|addr| addr.get_id());
 
+		let node_features = if self.advertise_onion_message_support.load(Ordering::Acquire) {
+			NodeFeatures::known() } else { NodeFeatures::known_without_onion_messages() };
 		let announcement = msgs::UnsignedNodeAnnouncement {
-			features: NodeFeatures::known(),
+			features: node_features,
 			timestamp: self.last_node_announcement_serial.fetch_add(1, Ordering::AcqRel) as u32,
 			node_id: self.get_our_node_id(),
 			rgb, alias, addresses,

lightning/src/ln/features.rs

@@ -550,6 +550,14 @@ impl InitFeatures {
 	}
 }
 
+impl NodeFeatures {
+	pub(crate) fn known_without_onion_messages() -> Self {
+		let mut features = Self::known();
+		features.flags[4] &= 0b00111111;
+		features
+	}
+}
+
 impl InvoiceFeatures {
 	/// Converts `InvoiceFeatures` to `Features<C>`. Only known `InvoiceFeatures` relevant to
 	/// context `C` are included in the result.
@@ -913,6 +921,8 @@ mod tests {
 		assert!(NodeFeatures::known().supports_onion_messages());
 		assert!(!InitFeatures::known().requires_onion_messages());
 		assert!(!NodeFeatures::known().requires_onion_messages());
+		assert!(!NodeFeatures::known_without_onion_messages().supports_onion_messages());
+		assert!(!NodeFeatures::known_without_onion_messages().requires_onion_messages());
 
 		assert!(InitFeatures::known().supports_zero_conf());
 		assert!(!InitFeatures::known().requires_zero_conf());