lightning 0.0.113

// This file is Copyright its original authors, visible in version control
// history.
//
// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
// You may not use this file except in accordance with one or both of these
// licenses.

//! Onion message testing and test utilities live here.

use crate::chain::keysinterface::{KeysInterface, Recipient};
use crate::ln::features::InitFeatures;
use crate::ln::msgs::{self, DecodeError, OnionMessageHandler};
use super::{BlindedPath, CustomOnionMessageContents, CustomOnionMessageHandler, Destination, OnionMessageContents, OnionMessenger, SendError};
use crate::util::ser::{Writeable, Writer};
use crate::util::test_utils;

use bitcoin::network::constants::Network;
use bitcoin::secp256k1::{PublicKey, Secp256k1};

use crate::io;
use crate::sync::Arc;

struct MessengerNode {
	keys_manager: Arc<test_utils::TestKeysInterface>,
	messenger: OnionMessenger<Arc<test_utils::TestKeysInterface>, Arc<test_utils::TestLogger>, Arc<TestCustomMessageHandler>>,
	logger: Arc<test_utils::TestLogger>,
}

impl MessengerNode {
	fn get_node_pk(&self) -> PublicKey {
		let secp_ctx = Secp256k1::new();
		PublicKey::from_secret_key(&secp_ctx, &self.keys_manager.get_node_secret(Recipient::Node).unwrap())
	}
}

#[derive(Clone)]
struct TestCustomMessage {}

const CUSTOM_MESSAGE_TYPE: u64 = 4242;
const CUSTOM_MESSAGE_CONTENTS: [u8; 32] = [42; 32];

impl CustomOnionMessageContents for TestCustomMessage {
	fn tlv_type(&self) -> u64 {
		CUSTOM_MESSAGE_TYPE
	}
}

impl Writeable for TestCustomMessage {
	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
		Ok(CUSTOM_MESSAGE_CONTENTS.write(w)?)
	}
}

struct TestCustomMessageHandler {}

impl CustomOnionMessageHandler for TestCustomMessageHandler {
	type CustomMessage = TestCustomMessage;
	fn handle_custom_message(&self, _msg: Self::CustomMessage) {}
	fn read_custom_message<R: io::Read>(&self, message_type: u64, buffer: &mut R) -> Result<Option<Self::CustomMessage>, DecodeError> where Self: Sized {
		if message_type == CUSTOM_MESSAGE_TYPE {
			let mut buf = Vec::new();
			buffer.read_to_end(&mut buf)?;
			assert_eq!(buf, CUSTOM_MESSAGE_CONTENTS);
			return Ok(Some(TestCustomMessage {}))
		}
		Ok(None)
	}
}

fn create_nodes(num_messengers: u8) -> Vec<MessengerNode> {
	let mut nodes = Vec::new();
	for i in 0..num_messengers {
		let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
		let seed = [i as u8; 32];
		let keys_manager = Arc::new(test_utils::TestKeysInterface::new(&seed, Network::Testnet));
		nodes.push(MessengerNode {
			keys_manager: keys_manager.clone(),
			messenger: OnionMessenger::new(keys_manager, logger.clone(), Arc::new(TestCustomMessageHandler {})),
			logger,
		});
	}
	for idx in 0..num_messengers - 1 {
		let i = idx as usize;
		let mut features = InitFeatures::empty();
		features.set_onion_messages_optional();
		let init_msg = msgs::Init { features, remote_network_address: None };
		nodes[i].messenger.peer_connected(&nodes[i + 1].get_node_pk(), &init_msg.clone()).unwrap();
		nodes[i + 1].messenger.peer_connected(&nodes[i].get_node_pk(), &init_msg.clone()).unwrap();
	}
	nodes
}

fn pass_along_path(path: &Vec<MessengerNode>, expected_path_id: Option<[u8; 32]>) {
	let mut prev_node = &path[0];
	let num_nodes = path.len();
	for (idx, node) in path.into_iter().skip(1).enumerate() {
		let events = prev_node.messenger.release_pending_msgs();
		let onion_msg =  {
			let msgs = events.get(&node.get_node_pk()).unwrap();
			assert_eq!(msgs.len(), 1);
			msgs[0].clone()
		};
		node.messenger.handle_onion_message(&prev_node.get_node_pk(), &onion_msg);
		if idx == num_nodes - 1 {
			node.logger.assert_log_contains(
				"lightning::onion_message::messenger".to_string(),
				format!("Received an onion message with path_id: {:02x?}", expected_path_id).to_string(), 1);
		}
		prev_node = node;
	}
}

#[test]
fn one_hop() {
	let nodes = create_nodes(2);
	let test_msg = OnionMessageContents::Custom(TestCustomMessage {});

	nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), test_msg, None).unwrap();
	pass_along_path(&nodes, None);
}

#[test]
fn two_unblinded_hops() {
	let nodes = create_nodes(3);
	let test_msg = OnionMessageContents::Custom(TestCustomMessage {});

	nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk()], Destination::Node(nodes[2].get_node_pk()), test_msg, None).unwrap();
	pass_along_path(&nodes, None);
}

#[test]
fn two_unblinded_two_blinded() {
	let nodes = create_nodes(5);
	let test_msg = OnionMessageContents::Custom(TestCustomMessage {});

	let secp_ctx = Secp256k1::new();
	let blinded_path = BlindedPath::new(&[nodes[3].get_node_pk(), nodes[4].get_node_pk()], &*nodes[4].keys_manager, &secp_ctx).unwrap();

	nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], Destination::BlindedPath(blinded_path), test_msg, None).unwrap();
	pass_along_path(&nodes, None);
}

#[test]
fn three_blinded_hops() {
	let nodes = create_nodes(4);
	let test_msg = OnionMessageContents::Custom(TestCustomMessage {});

	let secp_ctx = Secp256k1::new();
	let blinded_path = BlindedPath::new(&[nodes[1].get_node_pk(), nodes[2].get_node_pk(), nodes[3].get_node_pk()], &*nodes[3].keys_manager, &secp_ctx).unwrap();

	nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), test_msg, None).unwrap();
	pass_along_path(&nodes, None);
}

#[test]
fn too_big_packet_error() {
	// Make sure we error as expected if a packet is too big to send.
	let nodes = create_nodes(2);
	let test_msg = OnionMessageContents::Custom(TestCustomMessage {});

	let hop_node_id = nodes[1].get_node_pk();
	let hops = [hop_node_id; 400];
	let err = nodes[0].messenger.send_onion_message(&hops, Destination::Node(hop_node_id), test_msg, None).unwrap_err();
	assert_eq!(err, SendError::TooBigPacket);
}

#[test]
fn we_are_intro_node() {
	// If we are sending straight to a blinded path and we are the introduction node, we need to
	// advance the blinded path by 1 hop so the second hop is the new introduction node.
	let mut nodes = create_nodes(3);
	let test_msg = TestCustomMessage {};

	let secp_ctx = Secp256k1::new();
	let blinded_path = BlindedPath::new(&[nodes[0].get_node_pk(), nodes[1].get_node_pk(), nodes[2].get_node_pk()], &*nodes[2].keys_manager, &secp_ctx).unwrap();

	nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg.clone()), None).unwrap();
	pass_along_path(&nodes, None);

	// Try with a two-hop blinded path where we are the introduction node.
	let blinded_path = BlindedPath::new(&[nodes[0].get_node_pk(), nodes[1].get_node_pk()], &*nodes[1].keys_manager, &secp_ctx).unwrap();
	nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg), None).unwrap();
	nodes.remove(2);
	pass_along_path(&nodes, None);
}

#[test]
fn invalid_blinded_path_error() {
	// Make sure we error as expected if a provided blinded path has 0 or 1 hops.
	let nodes = create_nodes(3);
	let test_msg = TestCustomMessage {};

	// 0 hops
	let secp_ctx = Secp256k1::new();
	let mut blinded_path = BlindedPath::new(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], &*nodes[2].keys_manager, &secp_ctx).unwrap();
	blinded_path.blinded_hops.clear();
	let err = nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg.clone()), None).unwrap_err();
	assert_eq!(err, SendError::TooFewBlindedHops);

	// 1 hop
	let mut blinded_path = BlindedPath::new(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], &*nodes[2].keys_manager, &secp_ctx).unwrap();
	blinded_path.blinded_hops.remove(0);
	assert_eq!(blinded_path.blinded_hops.len(), 1);
	let err = nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg), None).unwrap_err();
	assert_eq!(err, SendError::TooFewBlindedHops);
}

#[test]
fn reply_path() {
	let nodes = create_nodes(4);
	let test_msg = TestCustomMessage {};
	let secp_ctx = Secp256k1::new();

	// Destination::Node
	let reply_path = BlindedPath::new(&[nodes[2].get_node_pk(), nodes[1].get_node_pk(), nodes[0].get_node_pk()], &*nodes[0].keys_manager, &secp_ctx).unwrap();
	nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], Destination::Node(nodes[3].get_node_pk()), OnionMessageContents::Custom(test_msg.clone()), Some(reply_path)).unwrap();
	pass_along_path(&nodes, None);
	// Make sure the last node successfully decoded the reply path.
	nodes[3].logger.assert_log_contains(
		"lightning::onion_message::messenger".to_string(),
		format!("Received an onion message with path_id None and a reply_path").to_string(), 1);

	// Destination::BlindedPath
	let blinded_path = BlindedPath::new(&[nodes[1].get_node_pk(), nodes[2].get_node_pk(), nodes[3].get_node_pk()], &*nodes[3].keys_manager, &secp_ctx).unwrap();
	let reply_path = BlindedPath::new(&[nodes[2].get_node_pk(), nodes[1].get_node_pk(), nodes[0].get_node_pk()], &*nodes[0].keys_manager, &secp_ctx).unwrap();

	nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg), Some(reply_path)).unwrap();
	pass_along_path(&nodes, None);
	nodes[3].logger.assert_log_contains(
		"lightning::onion_message::messenger".to_string(),
		format!("Received an onion message with path_id None and a reply_path").to_string(), 2);
}

#[test]
fn invalid_custom_message_type() {
	let nodes = create_nodes(2);

	struct InvalidCustomMessage{}
	impl CustomOnionMessageContents for InvalidCustomMessage {
		fn tlv_type(&self) -> u64 {
			// Onion message contents must have a TLV >= 64.
			63
		}
	}

	impl Writeable for InvalidCustomMessage {
		fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> { unreachable!() }
	}

	let test_msg = OnionMessageContents::Custom(InvalidCustomMessage {});
	let err = nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), test_msg, None).unwrap_err();
	assert_eq!(err, SendError::InvalidMessage);
}

#[test]
fn peer_buffer_full() {
	let nodes = create_nodes(2);
	let test_msg = TestCustomMessage {};
	for _ in 0..188 { // Based on MAX_PER_PEER_BUFFER_SIZE in OnionMessenger
		nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), OnionMessageContents::Custom(test_msg.clone()), None).unwrap();
	}
	let err = nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), OnionMessageContents::Custom(test_msg), None).unwrap_err();
	assert_eq!(err, SendError::BufferFull);
}