use ln::features::{InitFeatures, NodeFeatures};
use ln::msgs::{self, OnionMessageHandler};
use ln::onion_utils;
+use 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;
/// 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
///
/// # 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::{MaybeReadableArgs, Writeable, Writer};
+/// # use lightning::io;
/// # use std::sync::Arc;
/// # struct FakeLogger {};
/// # impl Logger for 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 (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<W: Writer>(&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
+/// }
+/// }
+/// impl MaybeReadableArgs<u64> for YourCustomMessage {
+/// fn read<R: io::Read>(r: &mut R, message_type: u64) -> Result<Option<Self>, DecodeError> {
+/// # unreachable!()
+/// // Read your custom onion message of type `message_type` from `r`, or return `None`
+/// // if the message type is unknown
+/// }
+/// }
+/// // 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();
///
-/// // 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]: <https://github.com/lightning/bolts/pull/798>
/// [`OnionMessenger`]: crate::onion_message::OnionMessenger
-pub struct OnionMessenger<Signer: Sign, K: Deref, L: Deref>
+pub struct OnionMessenger<Signer: Sign, K: Deref, L: Deref, CMH: Deref>
where K::Target: KeysInterface<Signer = Signer>,
L::Target: Logger,
+ CMH:: Target: CustomOnionMessageHandler,
{
keys_manager: K,
logger: L,
pending_messages: Mutex<HashMap<PublicKey, VecDeque<msgs::OnionMessage>>>,
secp_ctx: Secp256k1<secp256k1::All>,
+ custom_handler: CMH,
// Coming soon:
// invoice_handler: InvoiceHandler,
- // custom_handler: CustomHandler, // handles custom onion messages
}
/// The destination of an onion message.
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,
}
-impl<Signer: Sign, K: Deref, L: Deref> OnionMessenger<Signer, K, L>
+/// 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);
+}
+
+impl<Signer: Sign, K: Deref, L: Deref, CMH: Deref> OnionMessenger<Signer, K, L, CMH>
where K::Target: KeysInterface<Signer = Signer>,
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 {
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<BlindedRoute>) -> Result<(), SendError> {
+ pub fn send_onion_message<T: CustomOnionMessageContents>(&self, intermediate_nodes: &[PublicKey], destination: Destination, message: OnionMessageContents<T>, reply_path: Option<BlindedRoute>) -> 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) }
+
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 {
}
};
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();
false
}
-impl<Signer: Sign, K: Deref, L: Deref> OnionMessageHandler for OnionMessenger<Signer, K, L>
+impl<Signer: Sign, K: Deref, L: Deref, CMH: Deref> OnionMessageHandler for OnionMessenger<Signer, K, L, CMH>
where K::Target: KeysInterface<Signer = Signer>,
L::Target: Logger,
+ 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
match onion_utils::decode_next_hop(onion_decode_ss, &msg.onion_routing_packet.hop_data[..],
msg.onion_routing_packet.hmac, control_tlvs_ss)
{
- Ok((Payload::Receive {
- control_tlvs: ReceiveControlTlvs::Unblinded(ReceiveTlvs { path_id }), reply_path,
+ 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,
- "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
}
}
-impl<Signer: Sign, K: Deref, L: Deref> OnionMessageProvider for OnionMessenger<Signer, K, L>
+impl<Signer: Sign, K: Deref, L: Deref, CMH: Deref> OnionMessageProvider for OnionMessenger<Signer, K, L, CMH>
where K::Target: KeysInterface<Signer = Signer>,
L::Target: Logger,
+ CMH::Target: CustomOnionMessageHandler,
{
fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option<msgs::OnionMessage> {
let mut pending_msgs = self.pending_messages.lock().unwrap();
///
/// [`SimpleArcChannelManager`]: crate::ln::channelmanager::SimpleArcChannelManager
/// [`SimpleArcPeerManager`]: crate::ln::peer_handler::SimpleArcPeerManager
-pub type SimpleArcOnionMessenger<L> = OnionMessenger<InMemorySigner, Arc<KeysManager>, Arc<L>>;
+pub type SimpleArcOnionMessenger<L> = OnionMessenger<InMemorySigner, Arc<KeysManager>, Arc<L>, IgnoringMessageHandler>;
/// Useful for simplifying the parameters of [`SimpleRefChannelManager`] and
/// [`SimpleRefPeerManager`]. See their docs for more details.
///
///
/// [`SimpleRefChannelManager`]: crate::ln::channelmanager::SimpleRefChannelManager
/// [`SimpleRefPeerManager`]: crate::ln::peer_handler::SimpleRefPeerManager
-pub type SimpleRefOnionMessenger<'a, 'b, L> = OnionMessenger<InMemorySigner, &'a KeysManager, &'b L>;
+pub type SimpleRefOnionMessenger<'a, 'b, L> = OnionMessenger<InMemorySigner, &'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<T: secp256k1::Signing + secp256k1::Verification>(
- secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], destination: Destination, mut reply_path:
- Option<BlindedRoute>, session_priv: &SecretKey
-) -> Result<(Vec<(Payload, [u8; 32])>, Vec<onion_utils::OnionKeys>), secp256k1::Error> {
+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<BlindedRoute>, 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 onion_packet_keys = Vec::with_capacity(num_hops);
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() {
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());
});
})?;
- 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<onion_utils::OnionKeys>, prng_seed: [u8; 32]) -> Result<Packet, ()> {
+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, ()> {
// 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
projects / rust-lightning / blobdiff