X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fblinded_path%2Fmod.rs;h=c52df1651fe3a5b3a8aaf137113881a31478147f;hb=b20b1dbe678d12480f79c736b37ab10ab79a9b06;hp=a4128d6a39d8876bd90e1377d8c23c635584a651;hpb=efed905a4f90a3ca86b08cd6fb111e7c790ce20d;p=rust-lightning

diff --git a/lightning/src/blinded_path/mod.rs b/lightning/src/blinded_path/mod.rs
index a4128d6a..c52df165 100644
--- a/lightning/src/blinded_path/mod.rs
+++ b/lightning/src/blinded_path/mod.rs
@@ -11,11 +11,9 @@
 
 pub(crate) mod utils;
 
-use bitcoin::hashes::{Hash, HashEngine};
-use bitcoin::hashes::sha256::Hash as Sha256;
-use bitcoin::secp256k1::{self, PublicKey, Scalar, Secp256k1, SecretKey};
+use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey};
 
-use crate::chain::keysinterface::{EntropySource, NodeSigner, Recipient};
+use crate::sign::{EntropySource, NodeSigner, Recipient};
 use crate::onion_message::ControlTlvs;
 use crate::ln::msgs::DecodeError;
 use crate::ln::onion_utils;
@@ -27,44 +25,44 @@ use core::ops::Deref;
 use crate::io::{self, Cursor};
 use crate::prelude::*;
 
-/// Onion messages can be sent and received to blinded paths, which serve to hide the identity of
-/// the recipient.
-#[derive(Clone, Debug, PartialEq)]
+/// Onion messages and payments can be sent and received to blinded paths, which serve to hide the
+/// identity of the recipient.
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
 pub struct BlindedPath {
 	/// To send to a blinded path, the sender first finds a route to the unblinded
 	/// `introduction_node_id`, which can unblind its [`encrypted_payload`] to find out the onion
-	/// message's next hop and forward it along.
+	/// message or payment's next hop and forward it along.
 	///
 	/// [`encrypted_payload`]: BlindedHop::encrypted_payload
-	pub(crate) introduction_node_id: PublicKey,
+	pub introduction_node_id: PublicKey,
 	/// Used by the introduction node to decrypt its [`encrypted_payload`] to forward the onion
-	/// message.
+	/// message or payment.
 	///
 	/// [`encrypted_payload`]: BlindedHop::encrypted_payload
-	pub(crate) blinding_point: PublicKey,
+	pub blinding_point: PublicKey,
 	/// The hops composing the blinded path.
-	pub(crate) blinded_hops: Vec<BlindedHop>,
+	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.
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
 pub struct BlindedHop {
 	/// The blinded node id of this hop in a blinded path.
-	pub(crate) blinded_node_id: PublicKey,
+	pub blinded_node_id: PublicKey,
 	/// The encrypted payload intended for this hop in a blinded path.
 	// The node sending to this blinded path will later encode this payload into the onion packet for
 	// this hop.
-	pub(crate) encrypted_payload: Vec<u8>,
+	pub encrypted_payload: Vec<u8>,
 }
 
 impl BlindedPath {
-	/// Create a blinded path to be forwarded along `node_pks`. The last node pubkey in `node_pks`
-	/// will be the destination node.
+	/// 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.
 	//  TODO: make all payloads the same size with padding + add dummy hops
-	pub fn new<ES: EntropySource, T: secp256k1::Signing + secp256k1::Verification>
+	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(()) }
@@ -75,12 +73,13 @@ impl BlindedPath {
 		Ok(BlindedPath {
 			introduction_node_id,
 			blinding_point: PublicKey::from_secret_key(secp_ctx, &blinding_secret),
-			blinded_hops: blinded_hops(secp_ctx, node_pks, &blinding_secret).map_err(|_| ())?,
+			blinded_hops: blinded_message_hops(secp_ctx, node_pks, &blinding_secret).map_err(|_| ())?,
 		})
 	}
 
-	// Advance the blinded path by one hop, so make the second hop into the new introduction node.
-	pub(super) fn advance_by_one<NS: Deref, T: secp256k1::Signing + secp256k1::Verification>
+	// 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
 	{
@@ -96,14 +95,8 @@ impl BlindedPath {
 				let mut new_blinding_point = match next_blinding_override {
 					Some(blinding_point) => blinding_point,
 					None => {
-						let blinding_factor = {
-							let mut sha = Sha256::engine();
-							sha.input(&self.blinding_point.serialize()[..]);
-							sha.input(control_tlvs_ss.as_ref());
-							Sha256::from_engine(sha).into_inner()
-						};
-						self.blinding_point.mul_tweak(secp_ctx, &Scalar::from_be_bytes(blinding_factor).unwrap())
-							.map_err(|_| ())?
+						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);
@@ -115,8 +108,8 @@ impl BlindedPath {
 	}
 }
 
-/// Construct blinded hops for the given `unblinded_path`.
-fn blinded_hops<T: secp256k1::Signing + secp256k1::Verification>(
+/// Construct blinded onion message hops for the given `unblinded_path`.
+fn blinded_message_hops<T: secp256k1::Signing + secp256k1::Verification>(
 	secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], session_priv: &SecretKey
 ) -> Result<Vec<BlindedHop>, secp256k1::Error> {
 	let mut blinded_hops = Vec::with_capacity(unblinded_path.len());