X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fblinded_path%2Futils.rs;h=c62b4e6c2612cb52ee57321b747947d2100bd214;hb=b1abf32937db89ce9603636f2aefa3ff224c4fba;hp=a188274a5d2fccd0b2eeee67c77c16530c53e1aa;hpb=1b356619b3b178ef5a4f392056ed2fd5b7de2541;p=rust-lightning

diff --git a/lightning/src/blinded_path/utils.rs b/lightning/src/blinded_path/utils.rs
index a188274a..c62b4e6c 100644
--- a/lightning/src/blinded_path/utils.rs
+++ b/lightning/src/blinded_path/utils.rs
@@ -15,7 +15,7 @@ use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey, Scalar};
 use bitcoin::secp256k1::ecdh::SharedSecret;
 
-use super::BlindedPath;
+use super::{BlindedHop, BlindedPath};
 use crate::ln::msgs::DecodeError;
 use crate::ln::onion_utils;
 use crate::onion_message::Destination;
@@ -27,11 +27,15 @@ use crate::prelude::*;
 
 // TODO: DRY with onion_utils::construct_onion_keys_callback
 #[inline]
-pub(crate) fn construct_keys_callback<T: secp256k1::Signing + secp256k1::Verification,
-	FType: FnMut(PublicKey, SharedSecret, PublicKey, [u8; 32], Option<PublicKey>, Option<Vec<u8>>)>(
-	secp_ctx: &Secp256k1<T>, unblinded_path: &[PublicKey], destination: Option<Destination>,
-	session_priv: &SecretKey, mut callback: FType
-) -> Result<(), secp256k1::Error> {
+pub(crate) fn construct_keys_callback<'a, T, I, F>(
+	secp_ctx: &Secp256k1<T>, unblinded_path: I, destination: Option<Destination>,
+	session_priv: &SecretKey, mut callback: F
+) -> Result<(), secp256k1::Error>
+where
+	T: secp256k1::Signing + secp256k1::Verification,
+	I: Iterator<Item=&'a PublicKey>,
+	F: FnMut(PublicKey, SharedSecret, PublicKey, [u8; 32], Option<PublicKey>, Option<Vec<u8>>),
+{
 	let mut msg_blinding_point_priv = session_priv.clone();
 	let mut msg_blinding_point = PublicKey::from_secret_key(secp_ctx, &msg_blinding_point_priv);
 	let mut onion_packet_pubkey_priv = msg_blinding_point_priv.clone();
@@ -101,10 +105,32 @@ pub(crate) fn construct_keys_callback<T: secp256k1::Signing + secp256k1::Verific
 	Ok(())
 }
 
+// Panics if `unblinded_tlvs` length is less than `unblinded_pks` length
+pub(super) fn construct_blinded_hops<'a, T, I1, I2>(
+	secp_ctx: &Secp256k1<T>, unblinded_pks: I1, mut unblinded_tlvs: I2, session_priv: &SecretKey
+) -> Result<Vec<BlindedHop>, secp256k1::Error>
+where
+	T: secp256k1::Signing + secp256k1::Verification,
+	I1: Iterator<Item=&'a PublicKey>,
+	I2: Iterator,
+	I2::Item: Writeable
+{
+	let mut blinded_hops = Vec::with_capacity(unblinded_pks.size_hint().0);
+	construct_keys_callback(
+		secp_ctx, unblinded_pks, None, session_priv,
+		|blinded_node_id, _, _, encrypted_payload_rho, _, _| {
+			blinded_hops.push(BlindedHop {
+				blinded_node_id,
+				encrypted_payload: encrypt_payload(unblinded_tlvs.next().unwrap(), encrypted_payload_rho),
+			});
+		})?;
+	Ok(blinded_hops)
+}
+
 /// Encrypt TLV payload to be used as a [`crate::blinded_path::BlindedHop::encrypted_payload`].
-pub(super) fn encrypt_payload<P: Writeable>(payload: P, encrypted_tlvs_ss: [u8; 32]) -> Vec<u8> {
+fn encrypt_payload<P: Writeable>(payload: P, encrypted_tlvs_rho: [u8; 32]) -> Vec<u8> {
 	let mut writer = VecWriter(Vec::new());
-	let write_adapter = ChaChaPolyWriteAdapter::new(encrypted_tlvs_ss, &payload);
+	let write_adapter = ChaChaPolyWriteAdapter::new(encrypted_tlvs_rho, &payload);
 	write_adapter.write(&mut writer).expect("In-memory writes cannot fail");
 	writer.0
 }