f: Remove Readable for Padding

Author: shaavan

lightning/src/blinded_path/payment.rs

@@ -506,7 +506,10 @@ impl<'a> Writeable for BlindedPaymentTlvsRef<'a> {
 impl Readable for BlindedPaymentTlvs {
 	fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
 		_init_and_read_tlv_stream!(r, {
-			(1, _padding, option),
+			// Reasoning: Padding refers to filler data added to a packet to increase
+			// its size and obscure its actual length. Since padding contains no meaningful
+			// information, we can safely omit reading it here.
+			// (1, _padding, option),
 			(2, scid, option),
 			(8, next_blinding_override, option),
 			(10, payment_relay, option),
@@ -516,7 +519,6 @@ impl Readable for BlindedPaymentTlvs {
 			(65537, payment_context, option),
 			(65539, authentication, option),
 		});
-		let _padding: Option<utils::BlindedPathPadding> = _padding;
 
 		if let Some(short_channel_id) = scid {
 			if payment_secret.is_some() {

lightning/src/blinded_path/utils.rs

@@ -18,12 +18,9 @@ use bitcoin::secp256k1::{self, PublicKey, Scalar, Secp256k1, SecretKey};
 use super::message::BlindedMessagePath;
 use super::{BlindedHop, BlindedPath};
 use crate::crypto::streams::ChaChaPolyWriteAdapter;
-use crate::ln::msgs::DecodeError;
 use crate::ln::onion_utils;
 use crate::onion_message::messenger::Destination;
-use crate::util::ser::{Readable, Writeable};
-
-use crate::io;
+use crate::util::ser::Writeable;
 
 use core::borrow::Borrow;
 
@@ -201,15 +198,3 @@ fn encrypt_payload<P: Writeable>(payload: P, encrypted_tlvs_rho: [u8; 32]) -> Ve
 ///
 /// For more details, see the [BOLTs Specification - Encrypted Recipient Data](https://github.com/lightning/bolts/blob/8707471dbc23245fb4d84c5f5babac1197f1583e/04-onion-routing.md#inside-encrypted_recipient_data-encrypted_data_tlv).
 pub(crate) struct BlindedPathPadding {}
-impl Readable for BlindedPathPadding {
-	#[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 {})
-	}
-}

lightning/src/onion_message/packet.rs

@@ -13,7 +13,6 @@ use bitcoin::secp256k1::PublicKey;
 use bitcoin::secp256k1::ecdh::SharedSecret;
 
 use crate::blinded_path::message::{BlindedMessagePath, ForwardTlvs, NextMessageHop, ReceiveTlvs};
-use crate::blinded_path::utils::BlindedPathPadding;
 use crate::ln::msgs::DecodeError;
 use crate::ln::onion_utils;
 #[cfg(async_payments)]
@@ -342,13 +341,15 @@ pub(crate) enum ControlTlvs {
 impl Readable for ControlTlvs {
 	fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
 		_init_and_read_tlv_stream!(r, {
-			(1, _padding, option),
+			// Reasoning: Padding refers to filler data added to a packet to increase
+			// its size and obscure its actual length. Since padding contains no meaningful
+			// information, we can safely omit reading it here.
+			// (1, _padding, option),
 			(2, short_channel_id, option),
 			(4, next_node_id, option),
 			(8, next_blinding_override, option),
 			(65537, context, option),
 		});
-		let _padding: Option<BlindedPathPadding> = _padding;
 
 		let next_hop = match (short_channel_id, next_node_id) {
 			(Some(_), Some(_)) => return Err(DecodeError::InvalidValue),