//! Creating blinded paths and related utilities live here.
+pub mod payment;
pub(crate) mod message;
pub(crate) mod utils;
use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey};
-use crate::sign::{EntropySource, NodeSigner, Recipient};
-use crate::onion_message::ControlTlvs;
use crate::ln::msgs::DecodeError;
-use crate::ln::onion_utils;
-use crate::util::chacha20poly1305rfc::ChaChaPolyReadAdapter;
-use crate::util::ser::{FixedLengthReader, LengthReadableArgs, Readable, Writeable, Writer};
+use crate::offers::invoice::BlindedPayInfo;
+use crate::routing::gossip::{NodeId, ReadOnlyNetworkGraph};
+use crate::sign::EntropySource;
+use crate::util::ser::{Readable, Writeable, Writer};
-use core::mem;
-use core::ops::Deref;
-use crate::io::{self, Cursor};
+use crate::io;
use crate::prelude::*;
/// Onion messages and payments can be sent and received to blinded paths, which serve to hide the
pub blinded_hops: Vec<BlindedHop>,
}
-/// Used to construct the blinded hops portion of a blinded path. These hops cannot be identified
-/// by outside observers and thus can be used to hide the identity of the recipient.
+/// An encrypted payload and node id corresponding to a hop in a payment or onion message path, to
+/// be encoded in the sender's onion packet. These hops cannot be identified by outside observers
+/// and thus can be used to hide the identity of the recipient.
#[derive(Clone, Debug, Hash, PartialEq, Eq)]
pub struct BlindedHop {
- /// The blinded node id of this hop in a blinded path.
+ /// The blinded node id of this hop in a [`BlindedPath`].
pub blinded_node_id: PublicKey,
- /// The encrypted payload intended for this hop in a blinded path.
+ /// The encrypted payload intended for this hop in a [`BlindedPath`].
// The node sending to this blinded path will later encode this payload into the onion packet for
// this hop.
pub encrypted_payload: Vec<u8>,
}
impl BlindedPath {
+ /// Create a one-hop blinded path for a message.
+ pub fn one_hop_for_message<ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification>(
+ recipient_node_id: PublicKey, entropy_source: &ES, secp_ctx: &Secp256k1<T>
+ ) -> Result<Self, ()> {
+ Self::new_for_message(&[recipient_node_id], entropy_source, secp_ctx)
+ }
+
/// Create a blinded path for an onion message, to be forwarded along `node_pks`. The last node
/// pubkey in `node_pks` will be the destination node.
///
- /// Errors if less than two hops are provided or if `node_pk`(s) are invalid.
+ /// Errors if no hops are provided or if `node_pk`(s) are invalid.
// TODO: make all payloads the same size with padding + add dummy hops
- pub fn new_for_message<ES: EntropySource, T: secp256k1::Signing + secp256k1::Verification>
- (node_pks: &[PublicKey], entropy_source: &ES, secp_ctx: &Secp256k1<T>) -> Result<Self, ()>
- {
- if node_pks.len() < 2 { return Err(()) }
+ pub fn new_for_message<ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification>(
+ node_pks: &[PublicKey], entropy_source: &ES, secp_ctx: &Secp256k1<T>
+ ) -> Result<Self, ()> {
+ if node_pks.is_empty() { return Err(()) }
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 = node_pks[0];
})
}
- // Advance the blinded onion message path by one hop, so make the second hop into the new
- // introduction node.
- pub(super) fn advance_message_path_by_one<NS: Deref, T: secp256k1::Signing + secp256k1::Verification>
- (&mut self, node_signer: &NS, secp_ctx: &Secp256k1<T>) -> Result<(), ()>
- where NS::Target: NodeSigner
- {
- let control_tlvs_ss = node_signer.ecdh(Recipient::Node, &self.blinding_point, None)?;
- let rho = onion_utils::gen_rho_from_shared_secret(&control_tlvs_ss.secret_bytes());
- let encrypted_control_tlvs = self.blinded_hops.remove(0).encrypted_payload;
- let mut s = Cursor::new(&encrypted_control_tlvs);
- let mut reader = FixedLengthReader::new(&mut s, encrypted_control_tlvs.len() as u64);
- match ChaChaPolyReadAdapter::read(&mut reader, rho) {
- Ok(ChaChaPolyReadAdapter { readable: ControlTlvs::Forward(message::ForwardTlvs {
- mut next_node_id, next_blinding_override,
- })}) => {
- let mut new_blinding_point = match next_blinding_override {
- Some(blinding_point) => blinding_point,
- None => {
- onion_utils::next_hop_pubkey(secp_ctx, self.blinding_point,
- control_tlvs_ss.as_ref()).map_err(|_| ())?
- }
- };
- mem::swap(&mut self.blinding_point, &mut new_blinding_point);
- mem::swap(&mut self.introduction_node_id, &mut next_node_id);
- Ok(())
- },
- _ => Err(())
- }
+ /// Create a one-hop blinded path for a payment.
+ pub fn one_hop_for_payment<ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification>(
+ payee_node_id: PublicKey, payee_tlvs: payment::ReceiveTlvs, min_final_cltv_expiry_delta: u16,
+ entropy_source: &ES, secp_ctx: &Secp256k1<T>
+ ) -> Result<(BlindedPayInfo, Self), ()> {
+ // This value is not considered in pathfinding for 1-hop blinded paths, because it's intended to
+ // be in relation to a specific channel.
+ let htlc_maximum_msat = u64::max_value();
+ Self::new_for_payment(
+ &[], payee_node_id, payee_tlvs, htlc_maximum_msat, min_final_cltv_expiry_delta,
+ entropy_source, secp_ctx
+ )
+ }
+
+ /// Create a blinded path for a payment, to be forwarded along `intermediate_nodes`.
+ ///
+ /// Errors if:
+ /// * a provided node id is invalid
+ /// * [`BlindedPayInfo`] calculation results in an integer overflow
+ /// * any unknown features are required in the provided [`ForwardTlvs`]
+ ///
+ /// [`ForwardTlvs`]: crate::blinded_path::payment::ForwardTlvs
+ // TODO: make all payloads the same size with padding + add dummy hops
+ pub fn new_for_payment<ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification>(
+ intermediate_nodes: &[payment::ForwardNode], payee_node_id: PublicKey,
+ payee_tlvs: payment::ReceiveTlvs, htlc_maximum_msat: u64, min_final_cltv_expiry_delta: u16,
+ entropy_source: &ES, secp_ctx: &Secp256k1<T>
+ ) -> Result<(BlindedPayInfo, Self), ()> {
+ let blinding_secret_bytes = entropy_source.get_secure_random_bytes();
+ let blinding_secret = SecretKey::from_slice(&blinding_secret_bytes[..]).expect("RNG is busted");
+
+ let blinded_payinfo = payment::compute_payinfo(
+ intermediate_nodes, &payee_tlvs, htlc_maximum_msat, min_final_cltv_expiry_delta
+ )?;
+ Ok((blinded_payinfo, BlindedPath {
+ introduction_node_id: intermediate_nodes.first().map_or(payee_node_id, |n| n.node_id),
+ blinding_point: PublicKey::from_secret_key(secp_ctx, &blinding_secret),
+ blinded_hops: payment::blinded_hops(
+ secp_ctx, intermediate_nodes, payee_node_id, payee_tlvs, &blinding_secret
+ ).map_err(|_| ())?,
+ }))
+ }
+
+ /// Returns the introduction [`NodeId`] of the blinded path.
+ pub fn public_introduction_node_id<'a>(
+ &self, network_graph: &'a ReadOnlyNetworkGraph
+ ) -> Option<&'a NodeId> {
+ let node_id = NodeId::from_pubkey(&self.introduction_node_id);
+ network_graph.nodes().get_key_value(&node_id).map(|(key, _)| key)
}
}
projects / rust-lightning / blobdiff