X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fonion_message%2Fmessenger.rs;h=b884c2ffebd9f90abdbb6051e83e5c802aad4f8a;hb=1c8a06cf61921b5edd637c066ca8bd001183042d;hp=4cda2a4c671026b4a3d6f77ef085481bb100f0ba;hpb=88ec5da4b33985396e0e748f91d046151b4ea161;p=rust-lightning diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs index 4cda2a4c..b884c2ff 100644 --- a/lightning/src/onion_message/messenger.rs +++ b/lightning/src/onion_message/messenger.rs @@ -15,24 +15,27 @@ use bitcoin::hashes::hmac::{Hmac, HmacEngine}; use bitcoin::hashes::sha256::Hash as Sha256; use bitcoin::secp256k1::{self, PublicKey, Scalar, Secp256k1, SecretKey}; -use chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager, Recipient, Sign}; -use ln::features::{InitFeatures, NodeFeatures}; -use ln::msgs::{self, OnionMessageHandler}; -use ln::onion_utils; +use crate::chain::keysinterface::{KeysInterface, KeysManager, Recipient}; +use crate::ln::features::{InitFeatures, NodeFeatures}; +use crate::ln::msgs::{self, OnionMessageHandler}; +use crate::ln::onion_utils; +use crate::ln::peer_handler::IgnoringMessageHandler; use super::blinded_route::{BlindedRoute, ForwardTlvs, ReceiveTlvs}; +pub use super::packet::{CustomOnionMessageContents, OnionMessageContents}; use super::packet::{BIG_PACKET_HOP_DATA_LEN, ForwardControlTlvs, Packet, Payload, ReceiveControlTlvs, SMALL_PACKET_HOP_DATA_LEN}; use super::utils; -use util::events::OnionMessageProvider; -use util::logger::Logger; -use util::ser::Writeable; +use crate::util::events::OnionMessageProvider; +use crate::util::logger::Logger; +use crate::util::ser::Writeable; use core::ops::Deref; -use sync::{Arc, Mutex}; -use prelude::*; +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 empty onion messages is supported. +/// and receiving custom onion messages is supported. /// /// # Example /// @@ -41,8 +44,12 @@ use prelude::*; /// # use bitcoin::hashes::_export::_core::time::Duration; /// # use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey}; /// # use lightning::chain::keysinterface::{InMemorySigner, KeysManager, KeysInterface}; -/// # use lightning::onion_message::{BlindedRoute, Destination, OnionMessenger}; +/// # use lightning::ln::msgs::DecodeError; +/// # use lightning::ln::peer_handler::IgnoringMessageHandler; +/// # use lightning::onion_message::{BlindedRoute, CustomOnionMessageContents, Destination, OnionMessageContents, 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 { @@ -55,43 +62,60 @@ use prelude::*; /// # let node_secret = SecretKey::from_slice(&hex::decode("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 (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 {}; /// // Create the onion messenger. This must use the same `keys_manager` as is passed to your /// // ChannelManager. -/// let onion_messenger = OnionMessenger::new(&keys_manager, logger); +/// let onion_messenger = OnionMessenger::new(&keys_manager, logger, your_custom_message_handler); /// -/// // Send an empty onion message to a node id. +/// # struct YourCustomMessage {} +/// impl Writeable for YourCustomMessage { +/// fn write(&self, w: &mut W) -> Result<(), io::Error> { +/// # Ok(()) +/// // Write your custom onion message to `w` +/// } +/// } +/// impl CustomOnionMessageContents 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 reply_path = None; -/// onion_messenger.send_onion_message(&intermediate_hops, Destination::Node(destination_node_id), reply_path); +/// # 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); /// /// // Create a blinded route 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_route = BlindedRoute::new::(&hops, &keys_manager, &secp_ctx).unwrap(); +/// let blinded_route = BlindedRoute::new(&hops, &keys_manager, &secp_ctx).unwrap(); /// -/// // Send an empty onion message to a blinded route. +/// // Send a custom onion message to a blinded route. /// # let intermediate_hops = [hop_node_id1, hop_node_id2]; /// let reply_path = None; -/// onion_messenger.send_onion_message(&intermediate_hops, Destination::BlindedRoute(blinded_route), reply_path); +/// # let your_custom_message = YourCustomMessage {}; +/// let message = OnionMessageContents::Custom(your_custom_message); +/// onion_messenger.send_onion_message(&intermediate_hops, Destination::BlindedRoute(blinded_route), message, reply_path); /// ``` /// /// [offers]: /// [`OnionMessenger`]: crate::onion_message::OnionMessenger -pub struct OnionMessenger - where K::Target: KeysInterface, +pub struct OnionMessenger + where K::Target: KeysInterface, L::Target: Logger, + CMH:: Target: CustomOnionMessageHandler, { keys_manager: K, logger: L, pending_messages: Mutex>>, secp_ctx: Secp256k1, + custom_handler: CMH, // Coming soon: // invoice_handler: InvoiceHandler, - // custom_handler: CustomHandler, // handles custom onion messages } /// The destination of an onion message. @@ -114,7 +138,7 @@ impl Destination { /// Errors that may occur when [sending an onion message]. /// /// [sending an onion message]: OnionMessenger::send_onion_message -#[derive(Debug, PartialEq)] +#[derive(Debug, PartialEq, Eq)] pub enum SendError { /// Errored computing onion message packet keys. Secp256k1(secp256k1::Error), @@ -126,17 +150,50 @@ pub enum SendError { TooFewBlindedHops, /// Our next-hop peer was offline or does not support onion message forwarding. InvalidFirstHop, + /// Onion message contents must have a TLV type >= 64. + InvalidMessage, /// Our next-hop peer's buffer was full or our total outbound buffer was full. BufferFull, + /// Failed to retrieve our node id from the provided [`KeysInterface`]. + /// + /// [`KeysInterface`]: crate::chain::keysinterface::KeysInterface + GetNodeIdFailed, + /// We attempted to send to a blinded route where we are the introduction node, and failed to + /// advance the blinded route to make the second hop the new introduction node. Either + /// [`KeysInterface::ecdh`] failed, we failed to tweak the current blinding point to get the + /// new blinding point, or we were attempting to send to ourselves. + BlindedRouteAdvanceFailed, } -impl OnionMessenger - where K::Target: KeysInterface, +/// Handler for custom onion messages. If you are using [`SimpleArcOnionMessenger`], +/// [`SimpleRefOnionMessenger`], or prefer to ignore inbound custom onion messages, +/// [`IgnoringMessageHandler`] must be provided to [`OnionMessenger::new`]. Otherwise, a custom +/// implementation of this trait must be provided, with [`CustomMessage`] specifying the supported +/// message types. +/// +/// See [`OnionMessenger`] for example usage. +/// +/// [`IgnoringMessageHandler`]: crate::ln::peer_handler::IgnoringMessageHandler +/// [`CustomMessage`]: Self::CustomMessage +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); + /// 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>; +} + +impl OnionMessenger + where K::Target: KeysInterface, L::Target: Logger, + CMH::Target: CustomOnionMessageHandler, { /// Constructs a new `OnionMessenger` to send, forward, and delegate received onion messages to /// their respective handlers. - pub fn new(keys_manager: K, logger: L) -> Self { + pub fn new(keys_manager: K, logger: L, custom_handler: CMH) -> Self { let mut secp_ctx = Secp256k1::new(); secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes()); OnionMessenger { @@ -144,17 +201,34 @@ impl OnionMessenger pending_messages: Mutex::new(HashMap::new()), secp_ctx, logger, + custom_handler, } } - /// Send an empty onion message to `destination`, routing it through `intermediate_nodes`. + /// Send an onion message with contents `message` to `destination`, routing it through `intermediate_nodes`. /// See [`OnionMessenger`] for example usage. - pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], destination: Destination, reply_path: Option) -> Result<(), SendError> { + pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], mut destination: Destination, message: OnionMessageContents, reply_path: Option) -> Result<(), SendError> { if let Destination::BlindedRoute(BlindedRoute { ref blinded_hops, .. }) = destination { if blinded_hops.len() < 2 { return Err(SendError::TooFewBlindedHops); } } + let OnionMessageContents::Custom(ref msg) = message; + if msg.tlv_type() < 64 { return Err(SendError::InvalidMessage) } + + // If we are sending straight to a blinded route and we are the introduction node, we need to + // advance the blinded route by 1 hop so the second hop is the new introduction node. + if intermediate_nodes.len() == 0 { + if let Destination::BlindedRoute(ref mut blinded_route) = destination { + let our_node_id = self.keys_manager.get_node_id(Recipient::Node) + .map_err(|()| SendError::GetNodeIdFailed)?; + if blinded_route.introduction_node_id == our_node_id { + blinded_route.advance_by_one(&self.keys_manager, &self.secp_ctx) + .map_err(|()| SendError::BlindedRouteAdvanceFailed)?; + } + } + } + let blinding_secret_bytes = self.keys_manager.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 { @@ -167,7 +241,7 @@ impl OnionMessenger } }; let (packet_payloads, packet_keys) = packet_payloads_and_keys( - &self.secp_ctx, intermediate_nodes, destination, reply_path, &blinding_secret) + &self.secp_ctx, intermediate_nodes, destination, message, reply_path, &blinding_secret) .map_err(|e| SendError::Secp256k1(e))?; let prng_seed = self.keys_manager.get_secure_random_bytes(); @@ -221,9 +295,10 @@ fn outbound_buffer_full(peer_node_id: &PublicKey, buffer: &HashMap OnionMessageHandler for OnionMessenger - where K::Target: KeysInterface, +impl OnionMessageHandler for OnionMessenger + where K::Target: KeysInterface, L::Target: Logger, + CMH::Target: CustomOnionMessageHandler + Sized, { /// 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 @@ -252,15 +327,18 @@ impl OnionMessageHandler for OnionMessenger::Target as CustomOnionMessageHandler>::CustomMessage> { + message, control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path, }, None)) => { log_info!(self.logger, - "Received an onion message with path_id: {:02x?} and {}reply_path", - path_id, if reply_path.is_some() { "" } else { "no " }); + "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), + } }, Ok((Payload::Forward(ForwardControlTlvs::Unblinded(ForwardTlvs { next_node_id, next_blinding_override @@ -335,11 +413,12 @@ impl OnionMessageHandler for OnionMessenger Result<(), ()> { if init.features.supports_onion_messages() { let mut peers = self.pending_messages.lock().unwrap(); peers.insert(their_node_id.clone(), VecDeque::new()); } + Ok(()) } fn peer_disconnected(&self, their_node_id: &PublicKey, _no_connection_possible: bool) { @@ -360,9 +439,10 @@ impl OnionMessageHandler for OnionMessenger OnionMessageProvider for OnionMessenger - where K::Target: KeysInterface, +impl OnionMessageProvider for OnionMessenger + where K::Target: KeysInterface, L::Target: Logger, + CMH::Target: CustomOnionMessageHandler, { fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option { let mut pending_msgs = self.pending_messages.lock().unwrap(); @@ -382,7 +462,7 @@ impl OnionMessageProvider for OnionMessenger = OnionMessenger, Arc>; +pub type SimpleArcOnionMessenger = OnionMessenger, Arc, IgnoringMessageHandler>; /// Useful for simplifying the parameters of [`SimpleRefChannelManager`] and /// [`SimpleRefPeerManager`]. See their docs for more details. /// @@ -390,14 +470,14 @@ pub type SimpleArcOnionMessenger = OnionMessenger = OnionMessenger; +pub type SimpleRefOnionMessenger<'a, 'b, L> = OnionMessenger<&'a KeysManager, &'b 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, mut reply_path: - Option, session_priv: &SecretKey -) -> Result<(Vec<(Payload, [u8; 32])>, Vec), secp256k1::Error> { +fn packet_payloads_and_keys( + secp_ctx: &Secp256k1, unblinded_path: &[PublicKey], destination: Destination, + message: OnionMessageContents, 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); let mut onion_packet_keys = Vec::with_capacity(num_hops); @@ -410,6 +490,7 @@ fn packet_payloads_and_keys( let mut unblinded_path_idx = 0; 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() { @@ -429,20 +510,14 @@ fn packet_payloads_and_keys( next_blinding_override: Some(blinding_pt), })), control_tlvs_ss)); } - if let Some(encrypted_payload) = enc_payload_opt { - payloads.push((Payload::Forward(ForwardControlTlvs::Blinded(encrypted_payload)), - control_tlvs_ss)); - } else { debug_assert!(false); } - blinded_path_idx += 1; - } else if blinded_path_idx < num_blinded_hops - 1 && enc_payload_opt.is_some() { + } + 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 { - payloads.push((Payload::Receive { - control_tlvs: ReceiveControlTlvs::Blinded(encrypted_payload), - reply_path: reply_path.take(), - }, control_tlvs_ss)); + 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()); @@ -457,18 +532,25 @@ fn packet_payloads_and_keys( }); })?; - if let Some(control_tlvs_ss) = prev_control_tlvs_ss { + if let Some(control_tlvs) = final_control_tlvs { + payloads.push((Payload::Receive { + control_tlvs, + reply_path: reply_path.take(), + message, + }, prev_control_tlvs_ss.unwrap())); + } else { payloads.push((Payload::Receive { control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id: None, }), reply_path: reply_path.take(), - }, control_tlvs_ss)); + message, + }, prev_control_tlvs_ss.unwrap())); } Ok((payloads, onion_packet_keys)) } /// Errors if the serialized payload size exceeds onion_message::BIG_PACKET_HOP_DATA_LEN -fn construct_onion_message_packet(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