X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fonion_message%2Fmessenger.rs;h=723e105d044cf549cfd8f392e206782b38a479af;hb=d974a07e96199932e98f6c34b8f3e1f151b53500;hp=67ba81e820f4c72f790d8a0f930219541c0e48fe;hpb=86e2b0059fb1443146caddb7d752b44d512ad242;p=rust-lightning diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs index 67ba81e8..723e105d 100644 --- a/lightning/src/onion_message/messenger.rs +++ b/lightning/src/onion_message/messenger.rs @@ -19,16 +19,19 @@ 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}; +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; -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 crate::util::logger::Logger; use crate::util::ser::Writeable; +use core::fmt; use core::ops::Deref; use crate::io; use crate::sync::{Arc, Mutex}; @@ -59,7 +62,7 @@ use crate::prelude::*; /// # use lightning::blinded_path::BlindedPath; /// # use lightning::sign::KeysManager; /// # use lightning::ln::peer_handler::IgnoringMessageHandler; -/// # use lightning::onion_message::{CustomOnionMessageContents, Destination, MessageRouter, OnionMessageContents, 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; @@ -100,7 +103,7 @@ use crate::prelude::*; /// // 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 @@ -112,8 +115,7 @@ use crate::prelude::*; /// destination: Destination::Node(destination_node_id), /// }; /// let reply_path = None; -/// # let your_custom_message = YourCustomMessage {}; -/// let message = OnionMessageContents::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. @@ -127,12 +129,10 @@ use crate::prelude::*; /// destination: Destination::BlindedPath(blinded_path), /// }; /// let reply_path = None; -/// # let your_custom_message = YourCustomMessage {}; -/// let message = OnionMessageContents::Custom(your_custom_message); +/// # let message = YourCustomMessage {}; /// onion_messenger.send_onion_message(path, message, reply_path); /// ``` /// -/// [`OnionMessage`]: crate::ln::msgs::OnionMessage /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice pub struct OnionMessenger @@ -147,37 +147,52 @@ where entropy_source: ES, node_signer: NS, logger: L, - pending_messages: Mutex>>, + pending_messages: Mutex>>, secp_ctx: Secp256k1, message_router: MR, offers_handler: OMH, custom_handler: CMH, } -/// A trait defining behavior for routing an [`OnionMessage`]. +/// An [`OnionMessage`] for [`OnionMessenger`] to send. /// -/// [`OnionMessage`]: msgs::OnionMessage +/// These are obtained when released from [`OnionMessenger`]'s handlers after which they are +/// enqueued for sending. +pub struct PendingOnionMessage { + /// 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, +} + +/// A trait defining behavior for routing an [`OnionMessage`]. pub trait MessageRouter { /// Returns a route for sending an [`OnionMessage`] to the given [`Destination`]. - /// - /// [`OnionMessage`]: msgs::OnionMessage fn find_path( &self, sender: PublicKey, peers: Vec, destination: Destination ) -> Result; } -/// 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, _destination: Destination + &self, _sender: PublicKey, peers: Vec, destination: Destination ) -> Result { - Err(()) + if peers.contains(&destination.first_node()) { + Ok(OnionMessagePath { intermediate_nodes: vec![], destination }) + } else { + Err(()) + } } } -/// A path for sending an [`msgs::OnionMessage`]. +/// A path for sending an [`OnionMessage`]. #[derive(Clone)] pub struct OnionMessagePath { /// Nodes on the path between the sender and the destination. @@ -203,6 +218,13 @@ impl Destination { 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]. @@ -215,8 +237,8 @@ pub enum SendError { /// 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, @@ -248,43 +270,53 @@ pub enum SendError { 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; /// Read a custom message of type `message_type` from `buffer`, returning `Ok(None)` if the /// message type is unknown. fn read_custom_message(&self, message_type: u64, buffer: &mut R) -> Result, 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`]. + fn release_pending_custom_messages(&self) -> Vec>; } /// A processed incoming onion message, containing either a Forward (another onion message) /// or a Receive payload with decrypted contents. -pub enum PeeledOnion { +pub enum PeeledOnion { /// Forwarded onion, with the next node id and a new onion - Forward(PublicKey, msgs::OnionMessage), + Forward(PublicKey, OnionMessage), /// Received onion message, with decrypted contents, path_id, and reply path - Receive(OnionMessageContents, Option<[u8; 32]>, Option) + Receive(ParsedOnionMessageContents, Option<[u8; 32]>, Option) } -/// Create an onion message with contents `message` to the destination of `path`. -/// Returns (introduction_node_id, onion_msg) -pub fn create_onion_message( +/// 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( entropy_source: &ES, node_signer: &NS, secp_ctx: &Secp256k1, - path: OnionMessagePath, message: OnionMessageContents, reply_path: Option, -) -> Result<(PublicKey, msgs::OnionMessage), SendError> + path: OnionMessagePath, contents: T, reply_path: Option, +) -> 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.len() < 2 { + if blinded_hops.is_empty() { return Err(SendError::TooFewBlindedHops); } } - if message.tlv_type() < 64 { return Err(SendError::InvalidMessage) } + 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. @@ -301,8 +333,8 @@ where let blinding_secret_bytes = 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(&secp_ctx, &blinding_secret)) + 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)), @@ -311,24 +343,26 @@ where } }; let (packet_payloads, packet_keys) = packet_payloads_and_keys( - &secp_ctx, &intermediate_nodes, destination, message, reply_path, &blinding_secret) + &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((introduction_node_id, msgs::OnionMessage { + Ok((first_node_id, OnionMessage { blinding_point, onion_routing_packet })) } -/// Decode one layer of an incoming onion message -/// Returns either a Forward (another onion message), or Receive (decrypted content) -pub fn peel_onion( - node_signer: NS, secp_ctx: &Secp256k1, logger: L, custom_handler: CMH, - msg: &msgs::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( + msg: &OnionMessage, secp_ctx: &Secp256k1, node_signer: NS, logger: L, + custom_handler: CMH, ) -> Result::Target as CustomOnionMessageHandler>::CustomMessage>, ()> where NS::Target: NodeSigner, @@ -362,7 +396,7 @@ where 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::<<::Target as CustomOnionMessageHandler>::CustomMessage> { + Ok((Payload::Receive::::Target as CustomOnionMessageHandler>::CustomMessage>> { message, control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path, }, None)) => { Ok(PeeledOnion::Receive(message, path_id, reply_path)) @@ -388,7 +422,7 @@ where hop_data: new_packet_bytes, hmac: next_hop_hmac, }; - let onion_message = msgs::OnionMessage { + let onion_message = OnionMessage { blinding_point: match next_blinding_override { Some(blinding_point) => blinding_point, None => { @@ -449,21 +483,20 @@ where } } - /// Send an onion message with contents `message` to the destination of `path`. + /// Sends an [`OnionMessage`] with the given `contents` for sending to the destination of + /// `path`. /// /// See [`OnionMessenger`] for example usage. - pub fn send_onion_message( - &self, path: OnionMessagePath, message: OnionMessageContents, - reply_path: Option + pub fn send_onion_message( + &self, path: OnionMessagePath, contents: T, reply_path: Option ) -> Result<(), SendError> { - let (introduction_node_id, onion_msg) = create_onion_message( - &self.entropy_source, &self.node_signer, &self.secp_ctx, - path, message, reply_path + 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(&introduction_node_id, &pending_per_peer_msgs) { return Err(SendError::BufferFull) } - match pending_per_peer_msgs.entry(introduction_node_id) { + 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); @@ -472,58 +505,54 @@ where } } - fn respond_with_onion_message( - &self, response: OnionMessageContents, path_id: Option<[u8; 32]>, - reply_path: Option + fn handle_onion_message_response( + &self, response: Option, reply_path: Option, 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( + &self, contents: T, destination: Destination, reply_path: Option, + 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 when responding to onion message with \ - path_id {:02x?}", path_id - ); + log_warn!(self.logger, "Unable to retrieve node id {}", log_suffix); return; } }; let peers = self.pending_messages.lock().unwrap().keys().copied().collect(); - - let destination = match reply_path { - Some(reply_path) => Destination::BlindedPath(reply_path), - None => { - log_trace!( - self.logger, "Missing reply path when responding to onion message with path_id \ - {:02x?}", path_id - ); - return; - }, - }; - let path = match self.message_router.find_path(sender, peers, destination) { Ok(path) => path, Err(()) => { - log_trace!( - self.logger, "Failed to find path when responding to onion message with \ - path_id {:02x?}", path_id - ); + log_trace!(self.logger, "Failed to find path {}", log_suffix); return; }, }; - log_trace!(self.logger, "Responding to onion message with path_id {:02x?}", path_id); + log_trace!(self.logger, "Sending onion message {}", log_suffix); - if let Err(e) = self.send_onion_message(path, response, None) { - log_trace!( - self.logger, "Failed responding to onion message with path_id {:02x?}: {:?}", - path_id, e - ); + 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> { + pub(super) fn release_pending_msgs(&self) -> HashMap> { 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 @@ -535,7 +564,7 @@ where } } -fn outbound_buffer_full(peer_node_id: &PublicKey, buffer: &HashMap>) -> bool { +fn outbound_buffer_full(peer_node_id: &PublicKey, buffer: &HashMap>) -> 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; @@ -568,29 +597,34 @@ where 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) { - match peel_onion( - &*self.node_signer, &self.secp_ctx, &*self.logger, &*self.custom_handler, msg + 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" }); - let response = match message { - OnionMessageContents::Offers(msg) => { - self.offers_handler.handle_message(msg) - .map(|msg| OnionMessageContents::Offers(msg)) + + match message { + 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 + ) + ); }, - OnionMessageContents::Custom(msg) => { - self.custom_handler.handle_custom_message(msg) - .map(|msg| OnionMessageContents::Custom(msg)) + 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 + ) + ); }, - }; - if let Some(response) = response { - self.respond_with_onion_message(response, path_id, reply_path); } }, Ok(PeeledOnion::Forward(next_node_id, onion_message)) => { @@ -645,7 +679,26 @@ where features } - fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option { + // 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 { + // Enqueue any initiating `OffersMessage`s to send. + for message in self.offers_handler.release_pending_messages() { + let PendingOnionMessage { 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() { + let PendingOnionMessage { 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() @@ -663,12 +716,12 @@ where /// /// [`SimpleArcChannelManager`]: crate::ln::channelmanager::SimpleArcChannelManager /// [`SimpleArcPeerManager`]: crate::ln::peer_handler::SimpleArcPeerManager -pub type SimpleArcOnionMessenger = OnionMessenger< +pub type SimpleArcOnionMessenger = OnionMessenger< Arc, Arc, Arc, Arc, - IgnoringMessageHandler, + Arc>, IgnoringMessageHandler >; @@ -679,20 +732,22 @@ pub type SimpleArcOnionMessenger = OnionMessenger< /// /// [`SimpleRefChannelManager`]: crate::ln::channelmanager::SimpleRefChannelManager /// [`SimpleRefPeerManager`]: crate::ln::peer_handler::SimpleRefPeerManager -pub type SimpleRefOnionMessenger<'a, 'b, 'c, L> = OnionMessenger< +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( - secp_ctx: &Secp256k1, unblinded_path: &[PublicKey], destination: Destination, - message: OnionMessageContents, mut reply_path: Option, session_priv: &SecretKey +fn packet_payloads_and_keys( + secp_ctx: &Secp256k1, unblinded_path: &[PublicKey], destination: Destination, message: T, + mut reply_path: Option, session_priv: &SecretKey ) -> Result<(Vec<(Payload, [u8; 32])>, Vec), secp256k1::Error> { let num_hops = unblinded_path.len() + destination.num_hops(); let mut payloads = Vec::with_capacity(num_hops); @@ -768,7 +823,7 @@ fn packet_payloads_and_keys(payloads: Vec<(Payload, [u8; 32])>, onion_keys: Vec, prng_seed: [u8; 32]) -> Result { +fn construct_onion_message_packet(payloads: Vec<(Payload, [u8; 32])>, onion_keys: Vec, prng_seed: [u8; 32]) -> Result { // 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