use bitcoin::hashes::sha256::Hash as Sha256;
use bitcoin::secp256k1::{self, PublicKey, Scalar, Secp256k1, SecretKey};
-use crate::chain::keysinterface::{EntropySource, KeysManager, NodeSigner, Recipient};
+use crate::blinded_path::BlindedPath;
+use crate::blinded_path::message::{advance_path_by_one, ForwardTlvs, ReceiveTlvs};
+use crate::blinded_path::utils;
+use crate::sign::{EntropySource, KeysManager, NodeSigner, Recipient};
+#[cfg(not(c_bindings))]
+use crate::ln::channelmanager::{SimpleArcChannelManager, SimpleRefChannelManager};
use crate::ln::features::{InitFeatures, NodeFeatures};
-use crate::ln::msgs::{self, OnionMessageHandler};
+use crate::ln::msgs::{self, OnionMessage, OnionMessageHandler};
use crate::ln::onion_utils;
use crate::ln::peer_handler::IgnoringMessageHandler;
-use super::blinded_path::{BlindedPath, ForwardTlvs, ReceiveTlvs};
-pub use super::packet::{CustomOnionMessageContents, OnionMessageContents};
+pub use super::packet::OnionMessageContents;
+use super::packet::ParsedOnionMessageContents;
+use super::offers::OffersMessageHandler;
use super::packet::{BIG_PACKET_HOP_DATA_LEN, ForwardControlTlvs, Packet, Payload, ReceiveControlTlvs, SMALL_PACKET_HOP_DATA_LEN};
-use super::utils;
-use crate::util::events::OnionMessageProvider;
use crate::util::logger::Logger;
use crate::util::ser::Writeable;
+use core::fmt;
use core::ops::Deref;
use crate::io;
use crate::sync::{Arc, Mutex};
use crate::prelude::*;
-/// A sender, receiver and forwarder of onion messages. In upcoming releases, this object will be
-/// used to retrieve invoices and fulfill invoice requests from [offers]. Currently, only sending
-/// and receiving custom onion messages is supported.
+/// A sender, receiver and forwarder of [`OnionMessage`]s.
+///
+/// # Handling Messages
+///
+/// `OnionMessenger` implements [`OnionMessageHandler`], making it responsible for either forwarding
+/// messages to peers or delegating to the appropriate handler for the message type. Currently, the
+/// available handlers are:
+/// * [`OffersMessageHandler`], for responding to [`InvoiceRequest`]s and paying [`Bolt12Invoice`]s
+/// * [`CustomOnionMessageHandler`], for handling user-defined message types
+///
+/// # Sending Messages
+///
+/// [`OnionMessage`]s are sent initially using [`OnionMessenger::send_onion_message`]. When handling
+/// a message, the matched handler may return a response message which `OnionMessenger` will send
+/// on its behalf.
///
/// # Example
///
/// ```
/// # extern crate bitcoin;
/// # use bitcoin::hashes::_export::_core::time::Duration;
+/// # use bitcoin::hashes::hex::FromHex;
/// # use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
-/// # use lightning::chain::keysinterface::KeysManager;
+/// # use lightning::blinded_path::BlindedPath;
+/// # use lightning::sign::KeysManager;
/// # use lightning::ln::peer_handler::IgnoringMessageHandler;
-/// # use lightning::onion_message::{BlindedPath, CustomOnionMessageContents, Destination, OnionMessageContents, OnionMessenger};
+/// # use lightning::onion_message::{OnionMessageContents, Destination, MessageRouter, OnionMessagePath, OnionMessenger};
/// # use lightning::util::logger::{Logger, Record};
/// # use lightning::util::ser::{Writeable, Writer};
/// # use lightning::io;
/// # use std::sync::Arc;
/// # struct FakeLogger;
/// # impl Logger for FakeLogger {
-/// # fn log(&self, record: &Record) { unimplemented!() }
+/// # fn log(&self, record: Record) { unimplemented!() }
+/// # }
+/// # struct FakeMessageRouter {}
+/// # impl MessageRouter for FakeMessageRouter {
+/// # fn find_path(&self, sender: PublicKey, peers: Vec<PublicKey>, destination: Destination) -> Result<OnionMessagePath, ()> {
+/// # unimplemented!()
+/// # }
/// # }
/// # let seed = [42u8; 32];
/// # let time = Duration::from_secs(123456);
/// # let keys_manager = KeysManager::new(&seed, time.as_secs(), time.subsec_nanos());
/// # let logger = Arc::new(FakeLogger {});
-/// # let node_secret = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
+/// # let node_secret = SecretKey::from_slice(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
/// # let secp_ctx = Secp256k1::new();
/// # let hop_node_id1 = PublicKey::from_secret_key(&secp_ctx, &node_secret);
/// # let (hop_node_id2, hop_node_id3, hop_node_id4) = (hop_node_id1, hop_node_id1, hop_node_id1);
/// # let destination_node_id = hop_node_id1;
-/// # let your_custom_message_handler = IgnoringMessageHandler {};
+/// # let message_router = Arc::new(FakeMessageRouter {});
+/// # let custom_message_handler = IgnoringMessageHandler {};
+/// # let offers_message_handler = IgnoringMessageHandler {};
/// // Create the onion messenger. This must use the same `keys_manager` as is passed to your
/// // ChannelManager.
-/// let onion_messenger = OnionMessenger::new(&keys_manager, &keys_manager, logger, &your_custom_message_handler);
+/// let onion_messenger = OnionMessenger::new(
+/// &keys_manager, &keys_manager, logger, message_router, &offers_message_handler,
+/// &custom_message_handler
+/// );
///
/// # struct YourCustomMessage {}
/// impl Writeable for YourCustomMessage {
/// // Write your custom onion message to `w`
/// }
/// }
-/// impl CustomOnionMessageContents for YourCustomMessage {
+/// impl OnionMessageContents for YourCustomMessage {
/// fn tlv_type(&self) -> u64 {
/// # let your_custom_message_type = 42;
/// your_custom_message_type
/// }
/// }
/// // Send a custom onion message to a node id.
-/// let intermediate_hops = [hop_node_id1, hop_node_id2];
+/// let path = OnionMessagePath {
+/// intermediate_nodes: vec![hop_node_id1, hop_node_id2],
+/// destination: Destination::Node(destination_node_id),
+/// };
/// let reply_path = None;
-/// # let your_custom_message = YourCustomMessage {};
-/// let message = OnionMessageContents::Custom(your_custom_message);
-/// onion_messenger.send_onion_message(&intermediate_hops, Destination::Node(destination_node_id), message, reply_path);
+/// # let message = YourCustomMessage {};
+/// onion_messenger.send_onion_message(path, message, reply_path);
///
/// // Create a blinded path to yourself, for someone to send an onion message to.
/// # let your_node_id = hop_node_id1;
/// let hops = [hop_node_id3, hop_node_id4, your_node_id];
-/// let blinded_path = BlindedPath::new(&hops, &keys_manager, &secp_ctx).unwrap();
+/// let blinded_path = BlindedPath::new_for_message(&hops, &keys_manager, &secp_ctx).unwrap();
///
/// // Send a custom onion message to a blinded path.
-/// # let intermediate_hops = [hop_node_id1, hop_node_id2];
+/// let path = OnionMessagePath {
+/// intermediate_nodes: vec![hop_node_id1, hop_node_id2],
+/// destination: Destination::BlindedPath(blinded_path),
+/// };
/// let reply_path = None;
-/// # let your_custom_message = YourCustomMessage {};
-/// let message = OnionMessageContents::Custom(your_custom_message);
-/// onion_messenger.send_onion_message(&intermediate_hops, Destination::BlindedPath(blinded_path), message, reply_path);
+/// # let message = YourCustomMessage {};
+/// onion_messenger.send_onion_message(path, message, reply_path);
/// ```
///
-/// [offers]: <https://github.com/lightning/bolts/pull/798>
-/// [`OnionMessenger`]: crate::onion_message::OnionMessenger
-pub struct OnionMessenger<ES: Deref, NS: Deref, L: Deref, CMH: Deref>
- where ES::Target: EntropySource,
- NS::Target: NodeSigner,
- L::Target: Logger,
- CMH:: Target: CustomOnionMessageHandler,
+/// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
+/// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
+pub struct OnionMessenger<ES: Deref, NS: Deref, L: Deref, MR: Deref, OMH: Deref, CMH: Deref>
+where
+ ES::Target: EntropySource,
+ NS::Target: NodeSigner,
+ L::Target: Logger,
+ MR::Target: MessageRouter,
+ OMH::Target: OffersMessageHandler,
+ CMH:: Target: CustomOnionMessageHandler,
{
entropy_source: ES,
node_signer: NS,
logger: L,
- pending_messages: Mutex<HashMap<PublicKey, VecDeque<msgs::OnionMessage>>>,
+ pending_messages: Mutex<HashMap<PublicKey, VecDeque<OnionMessage>>>,
secp_ctx: Secp256k1<secp256k1::All>,
+ message_router: MR,
+ offers_handler: OMH,
custom_handler: CMH,
- // Coming soon:
- // invoice_handler: InvoiceHandler,
+}
+
+/// An [`OnionMessage`] for [`OnionMessenger`] to send.
+///
+/// These are obtained when released from [`OnionMessenger`]'s handlers after which they are
+/// enqueued for sending.
+#[cfg(not(c_bindings))]
+pub struct PendingOnionMessage<T: OnionMessageContents> {
+ /// The message contents to send in an [`OnionMessage`].
+ pub contents: T,
+
+ /// The destination of the message.
+ pub destination: Destination,
+
+ /// A reply path to include in the [`OnionMessage`] for a response.
+ pub reply_path: Option<BlindedPath>,
+}
+
+#[cfg(c_bindings)]
+/// An [`OnionMessage`] for [`OnionMessenger`] to send.
+///
+/// These are obtained when released from [`OnionMessenger`]'s handlers after which they are
+/// enqueued for sending.
+pub type PendingOnionMessage<T: OnionMessageContents> = (T, Destination, Option<BlindedPath>);
+
+pub(crate) fn new_pending_onion_message<T: OnionMessageContents>(
+ contents: T, destination: Destination, reply_path: Option<BlindedPath>
+) -> PendingOnionMessage<T> {
+ #[cfg(not(c_bindings))]
+ return PendingOnionMessage { contents, destination, reply_path };
+ #[cfg(c_bindings)]
+ return (contents, destination, reply_path);
+}
+
+/// A trait defining behavior for routing an [`OnionMessage`].
+pub trait MessageRouter {
+ /// Returns a route for sending an [`OnionMessage`] to the given [`Destination`].
+ fn find_path(
+ &self, sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
+ ) -> Result<OnionMessagePath, ()>;
+}
+
+/// A [`MessageRouter`] that can only route to a directly connected [`Destination`].
+pub struct DefaultMessageRouter;
+
+impl MessageRouter for DefaultMessageRouter {
+ fn find_path(
+ &self, _sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
+ ) -> Result<OnionMessagePath, ()> {
+ if peers.contains(&destination.first_node()) {
+ Ok(OnionMessagePath { intermediate_nodes: vec![], destination })
+ } else {
+ Err(())
+ }
+ }
+}
+
+/// A path for sending an [`OnionMessage`].
+#[derive(Clone)]
+pub struct OnionMessagePath {
+ /// Nodes on the path between the sender and the destination.
+ pub intermediate_nodes: Vec<PublicKey>,
+
+ /// The recipient of the message.
+ pub destination: Destination,
}
/// The destination of an onion message.
+#[derive(Clone)]
pub enum Destination {
/// We're sending this onion message to a node.
Node(PublicKey),
Destination::BlindedPath(BlindedPath { blinded_hops, .. }) => blinded_hops.len(),
}
}
+
+ fn first_node(&self) -> PublicKey {
+ match self {
+ Destination::Node(node_id) => *node_id,
+ Destination::BlindedPath(BlindedPath { introduction_node_id: node_id, .. }) => *node_id,
+ }
+ }
}
/// Errors that may occur when [sending an onion message].
/// Because implementations such as Eclair will drop onion messages where the message packet
/// exceeds 32834 bytes, we refuse to send messages where the packet exceeds this size.
TooBigPacket,
- /// The provided [`Destination`] was an invalid [`BlindedPath`], due to having fewer than two
- /// blinded hops.
+ /// The provided [`Destination`] was an invalid [`BlindedPath`] due to not having any blinded
+ /// hops.
TooFewBlindedHops,
/// Our next-hop peer was offline or does not support onion message forwarding.
InvalidFirstHop,
BufferFull,
/// Failed to retrieve our node id from the provided [`NodeSigner`].
///
- /// [`NodeSigner`]: crate::chain::keysinterface::NodeSigner
+ /// [`NodeSigner`]: crate::sign::NodeSigner
GetNodeIdFailed,
/// We attempted to send to a blinded path where we are the introduction node, and failed to
/// advance the blinded path to make the second hop the new introduction node. Either
pub trait CustomOnionMessageHandler {
/// The message known to the handler. To support multiple message types, you may want to make this
/// an enum with a variant for each supported message.
- type CustomMessage: CustomOnionMessageContents;
- /// Called with the custom message that was received.
- fn handle_custom_message(&self, msg: Self::CustomMessage);
+ type CustomMessage: OnionMessageContents;
+
+ /// Called with the custom message that was received, returning a response to send, if any.
+ ///
+ /// The returned [`Self::CustomMessage`], if any, is enqueued to be sent by [`OnionMessenger`].
+ fn handle_custom_message(&self, msg: Self::CustomMessage) -> Option<Self::CustomMessage>;
+
/// Read a custom message of type `message_type` from `buffer`, returning `Ok(None)` if the
/// message type is unknown.
fn read_custom_message<R: io::Read>(&self, message_type: u64, buffer: &mut R) -> Result<Option<Self::CustomMessage>, msgs::DecodeError>;
+
+ /// Releases any [`Self::CustomMessage`]s that need to be sent.
+ ///
+ /// Typically, this is used for messages initiating a message flow rather than in response to
+ /// another message. The latter should use the return value of [`Self::handle_custom_message`].
+ #[cfg(not(c_bindings))]
+ fn release_pending_custom_messages(&self) -> Vec<PendingOnionMessage<Self::CustomMessage>>;
+
+ /// Releases any [`Self::CustomMessage`]s that need to be sent.
+ ///
+ /// Typically, this is used for messages initiating a message flow rather than in response to
+ /// another message. The latter should use the return value of [`Self::handle_custom_message`].
+ #[cfg(c_bindings)]
+ fn release_pending_custom_messages(&self) -> Vec<(Self::CustomMessage, Destination, Option<BlindedPath>)>;
+}
+
+/// A processed incoming onion message, containing either a Forward (another onion message)
+/// or a Receive payload with decrypted contents.
+pub enum PeeledOnion<T: OnionMessageContents> {
+ /// Forwarded onion, with the next node id and a new onion
+ Forward(PublicKey, OnionMessage),
+ /// Received onion message, with decrypted contents, path_id, and reply path
+ Receive(ParsedOnionMessageContents<T>, Option<[u8; 32]>, Option<BlindedPath>)
+}
+
+/// Creates an [`OnionMessage`] with the given `contents` for sending to the destination of
+/// `path`.
+///
+/// Returns both the node id of the peer to send the message to and the message itself.
+pub fn create_onion_message<ES: Deref, NS: Deref, T: OnionMessageContents>(
+ entropy_source: &ES, node_signer: &NS, secp_ctx: &Secp256k1<secp256k1::All>,
+ path: OnionMessagePath, contents: T, reply_path: Option<BlindedPath>,
+) -> Result<(PublicKey, OnionMessage), SendError>
+where
+ ES::Target: EntropySource,
+ NS::Target: NodeSigner,
+{
+ let OnionMessagePath { intermediate_nodes, mut destination } = path;
+ if let Destination::BlindedPath(BlindedPath { ref blinded_hops, .. }) = destination {
+ if blinded_hops.is_empty() {
+ return Err(SendError::TooFewBlindedHops);
+ }
+ }
+
+ if contents.tlv_type() < 64 { return Err(SendError::InvalidMessage) }
+
+ // 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.
+ if intermediate_nodes.len() == 0 {
+ if let Destination::BlindedPath(ref mut blinded_path) = destination {
+ let our_node_id = node_signer.get_node_id(Recipient::Node)
+ .map_err(|()| SendError::GetNodeIdFailed)?;
+ if blinded_path.introduction_node_id == our_node_id {
+ advance_path_by_one(blinded_path, node_signer, &secp_ctx)
+ .map_err(|()| SendError::BlindedPathAdvanceFailed)?;
+ }
+ }
+ }
+
+ let blinding_secret_bytes = entropy_source.get_secure_random_bytes();
+ let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
+ let (first_node_id, blinding_point) = if let Some(first_node_id) = intermediate_nodes.first() {
+ (*first_node_id, PublicKey::from_secret_key(&secp_ctx, &blinding_secret))
+ } else {
+ match destination {
+ Destination::Node(pk) => (pk, PublicKey::from_secret_key(&secp_ctx, &blinding_secret)),
+ Destination::BlindedPath(BlindedPath { introduction_node_id, blinding_point, .. }) =>
+ (introduction_node_id, blinding_point),
+ }
+ };
+ let (packet_payloads, packet_keys) = packet_payloads_and_keys(
+ &secp_ctx, &intermediate_nodes, destination, contents, reply_path, &blinding_secret)
+ .map_err(|e| SendError::Secp256k1(e))?;
+
+ let prng_seed = entropy_source.get_secure_random_bytes();
+ let onion_routing_packet = construct_onion_message_packet(
+ packet_payloads, packet_keys, prng_seed).map_err(|()| SendError::TooBigPacket)?;
+
+ Ok((first_node_id, OnionMessage {
+ blinding_point,
+ onion_routing_packet
+ }))
}
-impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessenger<ES, NS, L, CMH>
- where ES::Target: EntropySource,
- NS::Target: NodeSigner,
- L::Target: Logger,
- CMH::Target: CustomOnionMessageHandler,
+/// Decode one layer of an incoming [`OnionMessage`].
+///
+/// Returns either the next layer of the onion for forwarding or the decrypted content for the
+/// receiver.
+pub fn peel_onion_message<NS: Deref, L: Deref, CMH: Deref>(
+ msg: &OnionMessage, secp_ctx: &Secp256k1<secp256k1::All>, node_signer: NS, logger: L,
+ custom_handler: CMH,
+) -> Result<PeeledOnion<<<CMH>::Target as CustomOnionMessageHandler>::CustomMessage>, ()>
+where
+ NS::Target: NodeSigner,
+ L::Target: Logger,
+ CMH::Target: CustomOnionMessageHandler,
+{
+ let control_tlvs_ss = match node_signer.ecdh(Recipient::Node, &msg.blinding_point, None) {
+ Ok(ss) => ss,
+ Err(e) => {
+ log_error!(logger, "Failed to retrieve node secret: {:?}", e);
+ return Err(());
+ }
+ };
+ let onion_decode_ss = {
+ let blinding_factor = {
+ let mut hmac = HmacEngine::<Sha256>::new(b"blinded_node_id");
+ hmac.input(control_tlvs_ss.as_ref());
+ Hmac::from_engine(hmac).to_byte_array()
+ };
+ match node_signer.ecdh(Recipient::Node, &msg.onion_routing_packet.public_key,
+ Some(&Scalar::from_be_bytes(blinding_factor).unwrap()))
+ {
+ Ok(ss) => ss.secret_bytes(),
+ Err(()) => {
+ log_trace!(logger, "Failed to compute onion packet shared secret");
+ return Err(());
+ }
+ }
+ };
+ match onion_utils::decode_next_untagged_hop(
+ onion_decode_ss, &msg.onion_routing_packet.hop_data[..], msg.onion_routing_packet.hmac,
+ (control_tlvs_ss, custom_handler.deref(), logger.deref())
+ ) {
+ Ok((Payload::Receive::<ParsedOnionMessageContents<<<CMH as Deref>::Target as CustomOnionMessageHandler>::CustomMessage>> {
+ message, control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path,
+ }, None)) => {
+ Ok(PeeledOnion::Receive(message, path_id, reply_path))
+ },
+ Ok((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs {
+ next_node_id, next_blinding_override
+ })), Some((next_hop_hmac, new_packet_bytes)))) => {
+ // TODO: we need to check whether `next_node_id` is our node, in which case this is a dummy
+ // blinded hop and this onion message is destined for us. In this situation, we should keep
+ // unwrapping the onion layers to get to the final payload. Since we don't have the option
+ // of creating blinded paths with dummy hops currently, we should be ok to not handle this
+ // for now.
+ let new_pubkey = match onion_utils::next_hop_pubkey(&secp_ctx, msg.onion_routing_packet.public_key, &onion_decode_ss) {
+ Ok(pk) => pk,
+ Err(e) => {
+ log_trace!(logger, "Failed to compute next hop packet pubkey: {}", e);
+ return Err(())
+ }
+ };
+ let outgoing_packet = Packet {
+ version: 0,
+ public_key: new_pubkey,
+ hop_data: new_packet_bytes,
+ hmac: next_hop_hmac,
+ };
+ let onion_message = OnionMessage {
+ blinding_point: match next_blinding_override {
+ Some(blinding_point) => blinding_point,
+ None => {
+ match onion_utils::next_hop_pubkey(
+ &secp_ctx, msg.blinding_point, control_tlvs_ss.as_ref()
+ ) {
+ Ok(bp) => bp,
+ Err(e) => {
+ log_trace!(logger, "Failed to compute next blinding point: {}", e);
+ return Err(())
+ }
+ }
+ }
+ },
+ onion_routing_packet: outgoing_packet,
+ };
+
+ Ok(PeeledOnion::Forward(next_node_id, onion_message))
+ },
+ Err(e) => {
+ log_trace!(logger, "Errored decoding onion message packet: {:?}", e);
+ Err(())
+ },
+ _ => {
+ log_trace!(logger, "Received bogus onion message packet, either the sender encoded a final hop as a forwarding hop or vice versa");
+ Err(())
+ },
+ }
+}
+
+impl<ES: Deref, NS: Deref, L: Deref, MR: Deref, OMH: Deref, CMH: Deref>
+OnionMessenger<ES, NS, L, MR, OMH, CMH>
+where
+ ES::Target: EntropySource,
+ NS::Target: NodeSigner,
+ L::Target: Logger,
+ MR::Target: MessageRouter,
+ OMH::Target: OffersMessageHandler,
+ CMH::Target: CustomOnionMessageHandler,
{
/// Constructs a new `OnionMessenger` to send, forward, and delegate received onion messages to
/// their respective handlers.
- pub fn new(entropy_source: ES, node_signer: NS, logger: L, custom_handler: CMH) -> Self {
+ pub fn new(
+ entropy_source: ES, node_signer: NS, logger: L, message_router: MR, offers_handler: OMH,
+ custom_handler: CMH
+ ) -> Self {
let mut secp_ctx = Secp256k1::new();
secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
OnionMessenger {
pending_messages: Mutex::new(HashMap::new()),
secp_ctx,
logger,
+ message_router,
+ offers_handler,
custom_handler,
}
}
- /// Send an onion message with contents `message` to `destination`, routing it through `intermediate_nodes`.
+ /// Sends an [`OnionMessage`] with the given `contents` for sending to the destination of
+ /// `path`.
+ ///
/// See [`OnionMessenger`] for example usage.
- pub fn send_onion_message<T: CustomOnionMessageContents>(&self, intermediate_nodes: &[PublicKey], mut destination: Destination, message: OnionMessageContents<T>, reply_path: Option<BlindedPath>) -> Result<(), SendError> {
- if let Destination::BlindedPath(BlindedPath { ref blinded_hops, .. }) = destination {
- if blinded_hops.len() < 2 {
- return Err(SendError::TooFewBlindedHops);
+ pub fn send_onion_message<T: OnionMessageContents>(
+ &self, path: OnionMessagePath, contents: T, reply_path: Option<BlindedPath>
+ ) -> Result<(), SendError> {
+ let (first_node_id, onion_msg) = create_onion_message(
+ &self.entropy_source, &self.node_signer, &self.secp_ctx, path, contents, reply_path
+ )?;
+
+ let mut pending_per_peer_msgs = self.pending_messages.lock().unwrap();
+ if outbound_buffer_full(&first_node_id, &pending_per_peer_msgs) { return Err(SendError::BufferFull) }
+ match pending_per_peer_msgs.entry(first_node_id) {
+ hash_map::Entry::Vacant(_) => Err(SendError::InvalidFirstHop),
+ hash_map::Entry::Occupied(mut e) => {
+ e.get_mut().push_back(onion_msg);
+ Ok(())
}
}
- let OnionMessageContents::Custom(ref msg) = message;
- if msg.tlv_type() < 64 { return Err(SendError::InvalidMessage) }
-
- // 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.
- if intermediate_nodes.len() == 0 {
- if let Destination::BlindedPath(ref mut blinded_path) = destination {
- let our_node_id = self.node_signer.get_node_id(Recipient::Node)
- .map_err(|()| SendError::GetNodeIdFailed)?;
- if blinded_path.introduction_node_id == our_node_id {
- blinded_path.advance_by_one(&self.node_signer, &self.secp_ctx)
- .map_err(|()| SendError::BlindedPathAdvanceFailed)?;
- }
+ }
+
+ fn handle_onion_message_response<T: OnionMessageContents>(
+ &self, response: Option<T>, reply_path: Option<BlindedPath>, log_suffix: fmt::Arguments
+ ) {
+ if let Some(response) = response {
+ match reply_path {
+ Some(reply_path) => {
+ self.find_path_and_enqueue_onion_message(
+ response, Destination::BlindedPath(reply_path), None, log_suffix
+ );
+ },
+ None => {
+ log_trace!(self.logger, "Missing reply path {}", log_suffix);
+ },
}
}
+ }
- let blinding_secret_bytes = self.entropy_source.get_secure_random_bytes();
- let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
- let (introduction_node_id, blinding_point) = if intermediate_nodes.len() != 0 {
- (intermediate_nodes[0], PublicKey::from_secret_key(&self.secp_ctx, &blinding_secret))
- } else {
- match destination {
- Destination::Node(pk) => (pk, PublicKey::from_secret_key(&self.secp_ctx, &blinding_secret)),
- Destination::BlindedPath(BlindedPath { introduction_node_id, blinding_point, .. }) =>
- (introduction_node_id, blinding_point),
+ fn find_path_and_enqueue_onion_message<T: OnionMessageContents>(
+ &self, contents: T, destination: Destination, reply_path: Option<BlindedPath>,
+ log_suffix: fmt::Arguments
+ ) {
+ let sender = match self.node_signer.get_node_id(Recipient::Node) {
+ Ok(node_id) => node_id,
+ Err(_) => {
+ log_warn!(self.logger, "Unable to retrieve node id {}", log_suffix);
+ return;
}
};
- let (packet_payloads, packet_keys) = packet_payloads_and_keys(
- &self.secp_ctx, intermediate_nodes, destination, message, reply_path, &blinding_secret)
- .map_err(|e| SendError::Secp256k1(e))?;
- let prng_seed = self.entropy_source.get_secure_random_bytes();
- let onion_routing_packet = construct_onion_message_packet(
- packet_payloads, packet_keys, prng_seed).map_err(|()| SendError::TooBigPacket)?;
+ let peers = self.pending_messages.lock().unwrap().keys().copied().collect();
+ let path = match self.message_router.find_path(sender, peers, destination) {
+ Ok(path) => path,
+ Err(()) => {
+ log_trace!(self.logger, "Failed to find path {}", log_suffix);
+ return;
+ },
+ };
- let mut pending_per_peer_msgs = self.pending_messages.lock().unwrap();
- if outbound_buffer_full(&introduction_node_id, &pending_per_peer_msgs) { return Err(SendError::BufferFull) }
- match pending_per_peer_msgs.entry(introduction_node_id) {
- hash_map::Entry::Vacant(_) => Err(SendError::InvalidFirstHop),
- hash_map::Entry::Occupied(mut e) => {
- e.get_mut().push_back(msgs::OnionMessage { blinding_point, onion_routing_packet });
- Ok(())
- }
+ log_trace!(self.logger, "Sending onion message {}", log_suffix);
+
+ if let Err(e) = self.send_onion_message(path, contents, reply_path) {
+ log_trace!(self.logger, "Failed sending onion message {}: {:?}", log_suffix, e);
+ return;
}
}
#[cfg(test)]
- pub(super) fn release_pending_msgs(&self) -> HashMap<PublicKey, VecDeque<msgs::OnionMessage>> {
+ pub(super) fn release_pending_msgs(&self) -> HashMap<PublicKey, VecDeque<OnionMessage>> {
let mut pending_msgs = self.pending_messages.lock().unwrap();
let mut msgs = HashMap::new();
// We don't want to disconnect the peers by removing them entirely from the original map, so we
}
}
-fn outbound_buffer_full(peer_node_id: &PublicKey, buffer: &HashMap<PublicKey, VecDeque<msgs::OnionMessage>>) -> bool {
+fn outbound_buffer_full(peer_node_id: &PublicKey, buffer: &HashMap<PublicKey, VecDeque<OnionMessage>>) -> bool {
const MAX_TOTAL_BUFFER_SIZE: usize = (1 << 20) * 128;
const MAX_PER_PEER_BUFFER_SIZE: usize = (1 << 10) * 256;
let mut total_buffered_bytes = 0;
false
}
-impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessageHandler for OnionMessenger<ES, NS, L, CMH>
- where ES::Target: EntropySource,
- NS::Target: NodeSigner,
- L::Target: Logger,
- CMH::Target: CustomOnionMessageHandler + Sized,
+impl<ES: Deref, NS: Deref, L: Deref, MR: Deref, OMH: Deref, CMH: Deref> OnionMessageHandler
+for OnionMessenger<ES, NS, L, MR, OMH, CMH>
+where
+ ES::Target: EntropySource,
+ NS::Target: NodeSigner,
+ L::Target: Logger,
+ MR::Target: MessageRouter,
+ OMH::Target: OffersMessageHandler,
+ CMH::Target: CustomOnionMessageHandler,
{
- /// Handle an incoming onion message. Currently, if a message was destined for us we will log, but
- /// soon we'll delegate the onion message to a handler that can generate invoices or send
- /// payments.
- fn handle_onion_message(&self, _peer_node_id: &PublicKey, msg: &msgs::OnionMessage) {
- let control_tlvs_ss = match self.node_signer.ecdh(Recipient::Node, &msg.blinding_point, None) {
- Ok(ss) => ss,
- Err(e) => {
- log_error!(self.logger, "Failed to retrieve node secret: {:?}", e);
- return
- }
- };
- let onion_decode_ss = {
- let blinding_factor = {
- let mut hmac = HmacEngine::<Sha256>::new(b"blinded_node_id");
- hmac.input(control_tlvs_ss.as_ref());
- Hmac::from_engine(hmac).into_inner()
- };
- match self.node_signer.ecdh(Recipient::Node, &msg.onion_routing_packet.public_key,
- Some(&Scalar::from_be_bytes(blinding_factor).unwrap()))
- {
- Ok(ss) => ss.secret_bytes(),
- Err(()) => {
- log_trace!(self.logger, "Failed to compute onion packet shared secret");
- return
- }
- }
- };
- match onion_utils::decode_next_untagged_hop(onion_decode_ss, &msg.onion_routing_packet.hop_data[..],
- msg.onion_routing_packet.hmac, (control_tlvs_ss, &*self.custom_handler))
- {
- Ok((Payload::Receive::<<<CMH as Deref>::Target as CustomOnionMessageHandler>::CustomMessage> {
- message, control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path,
- }, None)) => {
- log_info!(self.logger,
+ fn handle_onion_message(&self, _peer_node_id: &PublicKey, msg: &OnionMessage) {
+ match peel_onion_message(
+ msg, &self.secp_ctx, &*self.node_signer, &*self.logger, &*self.custom_handler
+ ) {
+ Ok(PeeledOnion::Receive(message, path_id, reply_path)) => {
+ log_trace!(self.logger,
"Received an onion message with path_id {:02x?} and {} reply_path",
path_id, if reply_path.is_some() { "a" } else { "no" });
+
match message {
- OnionMessageContents::Custom(msg) => self.custom_handler.handle_custom_message(msg),
+ ParsedOnionMessageContents::Offers(msg) => {
+ let response = self.offers_handler.handle_message(msg);
+ self.handle_onion_message_response(
+ response, reply_path, format_args!(
+ "when responding to Offers onion message with path_id {:02x?}",
+ path_id
+ )
+ );
+ },
+ ParsedOnionMessageContents::Custom(msg) => {
+ let response = self.custom_handler.handle_custom_message(msg);
+ self.handle_onion_message_response(
+ response, reply_path, format_args!(
+ "when responding to Custom onion message with path_id {:02x?}",
+ path_id
+ )
+ );
+ },
}
},
- Ok((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs {
- next_node_id, next_blinding_override
- })), Some((next_hop_hmac, new_packet_bytes)))) => {
- // TODO: we need to check whether `next_node_id` is our node, in which case this is a dummy
- // blinded hop and this onion message is destined for us. In this situation, we should keep
- // unwrapping the onion layers to get to the final payload. Since we don't have the option
- // of creating blinded paths with dummy hops currently, we should be ok to not handle this
- // for now.
- let new_pubkey = match onion_utils::next_hop_packet_pubkey(&self.secp_ctx, msg.onion_routing_packet.public_key, &onion_decode_ss) {
- Ok(pk) => pk,
- Err(e) => {
- log_trace!(self.logger, "Failed to compute next hop packet pubkey: {}", e);
- return
- }
- };
- let outgoing_packet = Packet {
- version: 0,
- public_key: new_pubkey,
- hop_data: new_packet_bytes,
- hmac: next_hop_hmac,
- };
- let onion_message = msgs::OnionMessage {
- blinding_point: match next_blinding_override {
- Some(blinding_point) => blinding_point,
- None => {
- let blinding_factor = {
- let mut sha = Sha256::engine();
- sha.input(&msg.blinding_point.serialize()[..]);
- sha.input(control_tlvs_ss.as_ref());
- Sha256::from_engine(sha).into_inner()
- };
- let next_blinding_point = msg.blinding_point;
- match next_blinding_point.mul_tweak(&self.secp_ctx, &Scalar::from_be_bytes(blinding_factor).unwrap()) {
- Ok(bp) => bp,
- Err(e) => {
- log_trace!(self.logger, "Failed to compute next blinding point: {}", e);
- return
- }
- }
- },
- },
- onion_routing_packet: outgoing_packet,
- };
-
+ Ok(PeeledOnion::Forward(next_node_id, onion_message)) => {
let mut pending_per_peer_msgs = self.pending_messages.lock().unwrap();
if outbound_buffer_full(&next_node_id, &pending_per_peer_msgs) {
log_trace!(self.logger, "Dropping forwarded onion message to peer {:?}: outbound buffer full", next_node_id);
e.get_mut().push_back(onion_message);
log_trace!(self.logger, "Forwarding an onion message to peer {}", next_node_id);
}
- };
+ }
},
Err(e) => {
- log_trace!(self.logger, "Errored decoding onion message packet: {:?}", e);
- },
- _ => {
- log_trace!(self.logger, "Received bogus onion message packet, either the sender encoded a final hop as a forwarding hop or vice versa");
- },
- };
+ log_error!(self.logger, "Failed to process onion message {:?}", e);
+ }
+ }
}
fn peer_connected(&self, their_node_id: &PublicKey, init: &msgs::Init, _inbound: bool) -> Result<(), ()> {
features.set_onion_messages_optional();
features
}
-}
-impl<ES: Deref, NS: Deref, L: Deref, CMH: Deref> OnionMessageProvider for OnionMessenger<ES, NS, L, CMH>
- where ES::Target: EntropySource,
- NS::Target: NodeSigner,
- L::Target: Logger,
- CMH::Target: CustomOnionMessageHandler,
-{
- fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option<msgs::OnionMessage> {
+ // Before returning any messages to send for the peer, this method will see if any messages were
+ // enqueued in the handler by users, find a path to the corresponding blinded path's introduction
+ // node, and then enqueue the message for sending to the first peer in the full path.
+ fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option<OnionMessage> {
+ // Enqueue any initiating `OffersMessage`s to send.
+ for message in self.offers_handler.release_pending_messages() {
+ #[cfg(not(c_bindings))]
+ let PendingOnionMessage { contents, destination, reply_path } = message;
+ #[cfg(c_bindings)]
+ let (contents, destination, reply_path) = message;
+ self.find_path_and_enqueue_onion_message(
+ contents, destination, reply_path, format_args!("when sending OffersMessage")
+ );
+ }
+
+ // Enqueue any initiating `CustomMessage`s to send.
+ for message in self.custom_handler.release_pending_custom_messages() {
+ #[cfg(not(c_bindings))]
+ let PendingOnionMessage { contents, destination, reply_path } = message;
+ #[cfg(c_bindings)]
+ let (contents, destination, reply_path) = message;
+ self.find_path_and_enqueue_onion_message(
+ contents, destination, reply_path, format_args!("when sending CustomMessage")
+ );
+ }
+
let mut pending_msgs = self.pending_messages.lock().unwrap();
if let Some(msgs) = pending_msgs.get_mut(&peer_node_id) {
return msgs.pop_front()
/// Useful for simplifying the parameters of [`SimpleArcChannelManager`] and
/// [`SimpleArcPeerManager`]. See their docs for more details.
///
-/// This is not exported to bindings users as `Arc`s don't make sense in bindings.
+/// This is not exported to bindings users as type aliases aren't supported in most languages.
///
/// [`SimpleArcChannelManager`]: crate::ln::channelmanager::SimpleArcChannelManager
/// [`SimpleArcPeerManager`]: crate::ln::peer_handler::SimpleArcPeerManager
-pub type SimpleArcOnionMessenger<L> = OnionMessenger<Arc<KeysManager>, Arc<KeysManager>, Arc<L>, IgnoringMessageHandler>;
+#[cfg(not(c_bindings))]
+pub type SimpleArcOnionMessenger<M, T, F, L> = OnionMessenger<
+ Arc<KeysManager>,
+ Arc<KeysManager>,
+ Arc<L>,
+ Arc<DefaultMessageRouter>,
+ Arc<SimpleArcChannelManager<M, T, F, L>>,
+ IgnoringMessageHandler
+>;
+
/// Useful for simplifying the parameters of [`SimpleRefChannelManager`] and
/// [`SimpleRefPeerManager`]. See their docs for more details.
///
-/// This is not exported to bindings users as general type aliases don't make sense in bindings.
+/// This is not exported to bindings users as type aliases aren't supported in most languages.
///
/// [`SimpleRefChannelManager`]: crate::ln::channelmanager::SimpleRefChannelManager
/// [`SimpleRefPeerManager`]: crate::ln::peer_handler::SimpleRefPeerManager
-pub type SimpleRefOnionMessenger<'a, 'b, L> = OnionMessenger<&'a KeysManager, &'a KeysManager, &'b L, IgnoringMessageHandler>;
+#[cfg(not(c_bindings))]
+pub type SimpleRefOnionMessenger<
+ 'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, M, T, F, L
+> = OnionMessenger<
+ &'a KeysManager,
+ &'a KeysManager,
+ &'b L,
+ &'i DefaultMessageRouter,
+ &'j SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, M, T, F, L>,
+ IgnoringMessageHandler
+>;
/// Construct onion packet payloads and keys for sending an onion message along the given
/// `unblinded_path` to the given `destination`.
-fn packet_payloads_and_keys<T: CustomOnionMessageContents, S: secp256k1::Signing + secp256k1::Verification>(
- secp_ctx: &Secp256k1<S>, unblinded_path: &[PublicKey], destination: Destination,
- message: OnionMessageContents<T>, mut reply_path: Option<BlindedPath>, session_priv: &SecretKey
+fn packet_payloads_and_keys<T: OnionMessageContents, S: secp256k1::Signing + secp256k1::Verification>(
+ secp_ctx: &Secp256k1<S>, unblinded_path: &[PublicKey], destination: Destination, message: T,
+ mut reply_path: Option<BlindedPath>, session_priv: &SecretKey
) -> Result<(Vec<(Payload<T>, [u8; 32])>, Vec<onion_utils::OnionKeys>), secp256k1::Error> {
let num_hops = unblinded_path.len() + destination.num_hops();
let mut payloads = Vec::with_capacity(num_hops);
let mut blinded_path_idx = 0;
let mut prev_control_tlvs_ss = None;
let mut final_control_tlvs = None;
- utils::construct_keys_callback(secp_ctx, unblinded_path, Some(destination), session_priv, |_, onion_packet_ss, ephemeral_pubkey, control_tlvs_ss, unblinded_pk_opt, enc_payload_opt| {
- if num_unblinded_hops != 0 && unblinded_path_idx < num_unblinded_hops {
- if let Some(ss) = prev_control_tlvs_ss.take() {
- payloads.push((Payload::Forward(ForwardControlTlvs::Unblinded(
- ForwardTlvs {
- next_node_id: unblinded_pk_opt.unwrap(),
- next_blinding_override: None,
- }
- )), ss));
+ utils::construct_keys_callback(secp_ctx, unblinded_path.iter(), Some(destination), session_priv,
+ |_, onion_packet_ss, ephemeral_pubkey, control_tlvs_ss, unblinded_pk_opt, enc_payload_opt| {
+ if num_unblinded_hops != 0 && unblinded_path_idx < num_unblinded_hops {
+ if let Some(ss) = prev_control_tlvs_ss.take() {
+ payloads.push((Payload::Forward(ForwardControlTlvs::Unblinded(
+ ForwardTlvs {
+ next_node_id: unblinded_pk_opt.unwrap(),
+ next_blinding_override: None,
+ }
+ )), ss));
+ }
+ prev_control_tlvs_ss = Some(control_tlvs_ss);
+ unblinded_path_idx += 1;
+ } else if let Some((intro_node_id, blinding_pt)) = intro_node_id_blinding_pt.take() {
+ if let Some(control_tlvs_ss) = prev_control_tlvs_ss.take() {
+ payloads.push((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs {
+ next_node_id: intro_node_id,
+ next_blinding_override: Some(blinding_pt),
+ })), control_tlvs_ss));
+ }
}
- prev_control_tlvs_ss = Some(control_tlvs_ss);
- unblinded_path_idx += 1;
- } else if let Some((intro_node_id, blinding_pt)) = intro_node_id_blinding_pt.take() {
- if let Some(control_tlvs_ss) = prev_control_tlvs_ss.take() {
- payloads.push((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs {
- next_node_id: intro_node_id,
- next_blinding_override: Some(blinding_pt),
- })), control_tlvs_ss));
+ if blinded_path_idx < num_blinded_hops.saturating_sub(1) && enc_payload_opt.is_some() {
+ payloads.push((Payload::Forward(ForwardControlTlvs::Blinded(enc_payload_opt.unwrap())),
+ control_tlvs_ss));
+ blinded_path_idx += 1;
+ } else if let Some(encrypted_payload) = enc_payload_opt {
+ final_control_tlvs = Some(ReceiveControlTlvs::Blinded(encrypted_payload));
+ prev_control_tlvs_ss = Some(control_tlvs_ss);
}
- }
- if blinded_path_idx < num_blinded_hops.saturating_sub(1) && enc_payload_opt.is_some() {
- payloads.push((Payload::Forward(ForwardControlTlvs::Blinded(enc_payload_opt.unwrap())),
- control_tlvs_ss));
- blinded_path_idx += 1;
- } else if let Some(encrypted_payload) = enc_payload_opt {
- final_control_tlvs = Some(ReceiveControlTlvs::Blinded(encrypted_payload));
- prev_control_tlvs_ss = Some(control_tlvs_ss);
- }
- let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(onion_packet_ss.as_ref());
- onion_packet_keys.push(onion_utils::OnionKeys {
- #[cfg(test)]
- shared_secret: onion_packet_ss,
- #[cfg(test)]
- blinding_factor: [0; 32],
- ephemeral_pubkey,
- rho,
- mu,
- });
- })?;
+ let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(onion_packet_ss.as_ref());
+ onion_packet_keys.push(onion_utils::OnionKeys {
+ #[cfg(test)]
+ shared_secret: onion_packet_ss,
+ #[cfg(test)]
+ blinding_factor: [0; 32],
+ ephemeral_pubkey,
+ rho,
+ mu,
+ });
+ }
+ )?;
if let Some(control_tlvs) = final_control_tlvs {
payloads.push((Payload::Receive {
}
/// Errors if the serialized payload size exceeds onion_message::BIG_PACKET_HOP_DATA_LEN
-fn construct_onion_message_packet<T: CustomOnionMessageContents>(payloads: Vec<(Payload<T>, [u8; 32])>, onion_keys: Vec<onion_utils::OnionKeys>, prng_seed: [u8; 32]) -> Result<Packet, ()> {
+fn construct_onion_message_packet<T: OnionMessageContents>(payloads: Vec<(Payload<T>, [u8; 32])>, onion_keys: Vec<onion_utils::OnionKeys>, prng_seed: [u8; 32]) -> Result<Packet, ()> {
// Spec rationale:
// "`len` allows larger messages to be sent than the standard 1300 bytes allowed for an HTLC
// onion, but this should be used sparingly as it is reduces anonymity set, hence the
BIG_PACKET_HOP_DATA_LEN
} else { return Err(()) };
- Ok(onion_utils::construct_onion_message_packet::<_, _>(
- payloads, onion_keys, prng_seed, hop_data_len))
+ onion_utils::construct_onion_message_packet::<_, _>(
+ payloads, onion_keys, prng_seed, hop_data_len)
}