X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fonion_message%2Fmessenger.rs;h=7eba3cdd254af6418132fc29bfac3cde59bd2292;hb=36e9725d9a9e9f71b31f8193daccfc96bb94090a;hp=3b18b1186febe9cffe38c13c1ff4ab4032c01c34;hpb=bf007ea7632b7b95c280440bc50713e55784e315;p=rust-lightning diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs index 3b18b118..7eba3cdd 100644 --- a/lightning/src/onion_message/messenger.rs +++ b/lightning/src/onion_message/messenger.rs @@ -28,9 +28,56 @@ use sync::{Arc, Mutex}; use 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]. +/// used to retrieve invoices and fulfill invoice requests from [offers]. Currently, only sending +/// and receiving empty onion messages is supported. +/// +/// # Example +/// +// Needs to be `ignore` until the `onion_message` module is made public, otherwise this is a test +// failure. +/// ```ignore +/// # extern crate bitcoin; +/// # 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::util::logger::{Logger, Record}; +/// # use std::sync::Arc; +/// # struct FakeLogger {}; +/// # impl Logger for FakeLogger { +/// # fn log(&self, record: &Record) { 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 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; +/// # +/// // 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); +/// +/// // Send an empty onion message to a node id. +/// let intermediate_hops = [hop_node_id1, hop_node_id2]; +/// onion_messenger.send_onion_message(&intermediate_hops, Destination::Node(destination_node_id)); +/// +/// // 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(); +/// +/// // Send an empty onion message to a blinded route. +/// # let intermediate_hops = [hop_node_id1, hop_node_id2]; +/// onion_messenger.send_onion_message(&intermediate_hops, Destination::BlindedRoute(blinded_route)); +/// ``` /// /// [offers]: +/// [`OnionMessenger`]: crate::onion_message::OnionMessenger pub struct OnionMessenger where K::Target: KeysInterface, L::Target: Logger, @@ -61,6 +108,21 @@ impl Destination { } } +/// Errors that may occur when [sending an onion message]. +/// +/// [sending an onion message]: OnionMessenger::send_onion_message +#[derive(Debug, PartialEq)] +pub enum SendError { + /// Errored computing onion message packet keys. + Secp256k1(secp256k1::Error), + /// 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 [`BlindedRoute`], due to having fewer than two + /// blinded hops. + TooFewBlindedHops, +} + impl OnionMessenger where K::Target: KeysInterface, L::Target: Logger, @@ -79,7 +141,13 @@ impl OnionMessenger } /// Send an empty onion message to `destination`, routing it through `intermediate_nodes`. - pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], destination: Destination) -> Result<(), secp256k1::Error> { + /// See [`OnionMessenger`] for example usage. + pub fn send_onion_message(&self, intermediate_nodes: &[PublicKey], destination: Destination) -> Result<(), SendError> { + if let Destination::BlindedRoute(BlindedRoute { ref blinded_hops, .. }) = destination { + if blinded_hops.len() < 2 { + return Err(SendError::TooFewBlindedHops); + } + } 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 { @@ -92,10 +160,12 @@ impl OnionMessenger } }; let (packet_payloads, packet_keys) = packet_payloads_and_keys( - &self.secp_ctx, intermediate_nodes, destination, &blinding_secret)?; + &self.secp_ctx, intermediate_nodes, destination, &blinding_secret) + .map_err(|e| SendError::Secp256k1(e))?; let prng_seed = self.keys_manager.get_secure_random_bytes(); - let onion_packet = construct_onion_message_packet(packet_payloads, packet_keys, prng_seed); + let onion_packet = construct_onion_message_packet( + packet_payloads, packet_keys, prng_seed).map_err(|()| SendError::TooBigPacket)?; let mut pending_per_peer_msgs = self.pending_messages.lock().unwrap(); let pending_msgs = pending_per_peer_msgs.entry(introduction_node_id).or_insert(Vec::new()); @@ -198,6 +268,14 @@ impl OnionMessenger }, }; } + + #[cfg(test)] + pub(super) fn release_pending_msgs(&self) -> HashMap> { + let mut pending_msgs = self.pending_messages.lock().unwrap(); + let mut msgs = HashMap::new(); + core::mem::swap(&mut *pending_msgs, &mut msgs); + msgs + } } // TODO: parameterize the below Simple* types with OnionMessenger and handle the messages it @@ -287,7 +365,8 @@ fn packet_payloads_and_keys( Ok((payloads, onion_packet_keys)) } -fn construct_onion_message_packet(payloads: Vec<(Payload, [u8; 32])>, onion_keys: Vec, prng_seed: [u8; 32]) -> Packet { +/// 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 { // 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 @@ -297,7 +376,8 @@ fn construct_onion_message_packet(payloads: Vec<(Payload, [u8; 32])>, onion_keys SMALL_PACKET_HOP_DATA_LEN } else if payloads_ser_len <= BIG_PACKET_HOP_DATA_LEN { BIG_PACKET_HOP_DATA_LEN - } else { payloads_ser_len }; + } else { return Err(()) }; - onion_utils::construct_onion_message_packet::<_, _>(payloads, onion_keys, prng_seed, hop_data_len) + Ok(onion_utils::construct_onion_message_packet::<_, _>( + payloads, onion_keys, prng_seed, hop_data_len)) }