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, OnionMessage, OnionMessageHandler};
use crate::ln::onion_utils;
use crate::ln::peer_handler::IgnoringMessageHandler;
-pub use super::packet::{CustomOnionMessageContents, ParsedOnionMessageContents};
+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 crate::util::logger::Logger;
/// # use lightning::blinded_path::BlindedPath;
/// # use lightning::sign::KeysManager;
/// # use lightning::ln::peer_handler::IgnoringMessageHandler;
-/// # use lightning::onion_message::{CustomOnionMessageContents, Destination, MessageRouter, ParsedOnionMessageContents, OnionMessagePath, 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;
/// // 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
/// destination: Destination::Node(destination_node_id),
/// };
/// let reply_path = None;
-/// # let your_custom_message = YourCustomMessage {};
-/// let message = ParsedOnionMessageContents::Custom(your_custom_message);
+/// # 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.
/// destination: Destination::BlindedPath(blinded_path),
/// };
/// let reply_path = None;
-/// # let your_custom_message = YourCustomMessage {};
-/// let message = ParsedOnionMessageContents::Custom(your_custom_message);
+/// # let message = YourCustomMessage {};
/// onion_messenger.send_onion_message(path, message, reply_path);
/// ```
///
custom_handler: CMH,
}
+/// 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`].
) -> Result<OnionMessagePath, ()>;
}
-/// A [`MessageRouter`] that always fails.
+/// 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
+ &self, _sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
) -> Result<OnionMessagePath, ()> {
- Err(())
+ if peers.contains(&destination.first_node()) {
+ Ok(OnionMessagePath { intermediate_nodes: vec![], destination })
+ } else {
+ Err(())
+ }
}
}
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,
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;
+ 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<CM: CustomOnionMessageContents> {
+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<CM>, Option<[u8; 32]>, Option<BlindedPath>)
+ 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: CustomOnionMessageContents>(
+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: ParsedOnionMessageContents<T>,
- reply_path: Option<BlindedPath>,
+ path: OnionMessagePath, contents: T, reply_path: Option<BlindedPath>,
) -> Result<(PublicKey, OnionMessage), SendError>
where
ES::Target: EntropySource,
{
let OnionMessagePath { intermediate_nodes, mut destination } = path;
if let Destination::BlindedPath(BlindedPath { ref blinded_hops, .. }) = destination {
- if blinded_hops.len() < 2 {
+ if blinded_hops.is_empty() {
return Err(SendError::TooFewBlindedHops);
}
}
}))
}
-/// Decode one layer of an incoming onion message
-/// Returns either a Forward (another onion message), or Receive (decrypted content)
-pub fn peel_onion<NS: Deref, L: Deref, CMH: Deref>(
- node_signer: NS, secp_ctx: &Secp256k1<secp256k1::All>, logger: L, custom_handler: CMH,
- msg: &OnionMessage,
+/// 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,
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::<<<CMH as Deref>::Target as CustomOnionMessageHandler>::CustomMessage> {
+ 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))
/// `path`.
///
/// See [`OnionMessenger`] for example usage.
- pub fn send_onion_message<T: CustomOnionMessageContents>(
- &self, path: OnionMessagePath, contents: ParsedOnionMessageContents<T>,
- reply_path: Option<BlindedPath>
+ 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
}
}
- fn find_path_and_enqueue_onion_message<T: CustomOnionMessageContents>(
- &self, contents: ParsedOnionMessageContents<T>, destination: Destination,
+ 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);
+ },
+ }
+ }
+ }
+
+ 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) {
log_trace!(self.logger, "Sending onion message {}", log_suffix);
- if let Err(e) = self.send_onion_message(path, contents, None) {
+ if let Err(e) = self.send_onion_message(path, contents, reply_path) {
log_trace!(self.logger, "Failed sending onion message {}: {:?}", log_suffix, e);
return;
}
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: &OnionMessage) {
- match peel_onion(
- &*self.node_signer, &self.secp_ctx, &*self.logger, &*self.custom_handler, msg
+ 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" });
- let response = match message {
+
+ match message {
ParsedOnionMessageContents::Offers(msg) => {
- self.offers_handler.handle_message(msg)
- .map(|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) => {
- self.custom_handler.handle_custom_message(msg)
- .map(|msg| ParsedOnionMessageContents::Custom(msg))
- },
- };
- if let Some(response) = response {
- match reply_path {
- Some(reply_path) => {
- self.find_path_and_enqueue_onion_message(
- response, Destination::BlindedPath(reply_path), format_args!(
- "when responding to onion message with path_id {:02x?}", path_id
- )
- );
- },
- None => {
- log_trace!(
- self.logger,
- "Missing reply path when responding to onion message with path_id {:02x?}",
+ 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(PeeledOnion::Forward(next_node_id, onion_message)) => {
features
}
+ // 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<
+#[cfg(not(c_bindings))]
+pub type SimpleArcOnionMessenger<M, T, F, L> = OnionMessenger<
Arc<KeysManager>,
Arc<KeysManager>,
Arc<L>,
Arc<DefaultMessageRouter>,
- IgnoringMessageHandler,
+ 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, 'c, L> = OnionMessenger<
+#[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,
- &'c DefaultMessageRouter,
- IgnoringMessageHandler,
+ &'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: ParsedOnionMessageContents<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);
}
/// 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