X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fblinded_path%2Futils.rs;h=1ac6519452c1eb10af3757240d41a046d381efaa;hb=9777485ed70689d55caf988b13ff7b7a0204429f;hp=1993ad932267db8f2d2c8a98f999f2726530b833;hpb=607727fae793e86f23249afddb0c10018312607f;p=rust-lightning

diff --git a/lightning/src/blinded_path/utils.rs b/lightning/src/blinded_path/utils.rs
index 1993ad93..1ac65194 100644
--- a/lightning/src/blinded_path/utils.rs
+++ b/lightning/src/blinded_path/utils.rs
@@ -16,18 +16,26 @@ use bitcoin::secp256k1::{self, PublicKey, Secp256k1, SecretKey, Scalar};
 use bitcoin::secp256k1::ecdh::SharedSecret;
 
 use super::BlindedPath;
+use crate::ln::msgs::DecodeError;
 use crate::ln::onion_utils;
 use crate::onion_message::Destination;
+use crate::util::chacha20poly1305rfc::ChaChaPolyWriteAdapter;
+use crate::util::ser::{Readable, VecWriter, Writeable};
 
+use crate::io;
 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();
@@ -96,3 +104,26 @@ pub(crate) fn construct_keys_callback<T: secp256k1::Signing + secp256k1::Verific
 	}
 	Ok(())
 }
+
+/// 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> {
+	let mut writer = VecWriter(Vec::new());
+	let write_adapter = ChaChaPolyWriteAdapter::new(encrypted_tlvs_ss, &payload);
+	write_adapter.write(&mut writer).expect("In-memory writes cannot fail");
+	writer.0
+}
+
+/// Blinded path encrypted payloads may be padded to ensure they are equal length.
+///
+/// Reads padding to the end, ignoring what's read.
+pub(crate) struct Padding {}
+impl Readable for Padding {
+	#[inline]
+	fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+		loop {
+			let mut buf = [0; 8192];
+			if reader.read(&mut buf[..])? == 0 { break; }
+		}
+		Ok(Self {})
+	}
+}