f fix LSP message read

Author: valentinewallace

lightning-custom-message/src/lib.rs

@@ -24,7 +24,7 @@
 //! use lightning::ln::peer_handler::CustomMessageHandler;
 //! use lightning::ln::wire::{CustomMessageReader, self};
 //! # use lightning::types::features::{InitFeatures, NodeFeatures};
-//! use lightning::util::ser::Writeable;
+//! use lightning::util::ser::{LengthLimitedRead, Writeable};
 //! # use lightning::util::ser::Writer;
 //!
 //! // Assume that `FooHandler` and `BarHandler` are defined in one crate and `BazHandler` is
@@ -52,7 +52,7 @@
 //! impl CustomMessageReader for FooHandler {
 //!     // ...
 //! #     type CustomMessage = Foo;
-//! #     fn read<R: io::Read>(
+//! #     fn read<R: LengthLimitedRead>(
 //! #         &self, _message_type: u16, _buffer: &mut R
 //! #     ) -> Result<Option<Self::CustomMessage>, DecodeError> {
 //! #         unimplemented!()
@@ -104,7 +104,7 @@
 //! impl CustomMessageReader for BarHandler {
 //!     // ...
 //! #     type CustomMessage = Bar;
-//! #     fn read<R: io::Read>(
+//! #     fn read<R: LengthLimitedRead>(
 //! #         &self, _message_type: u16, _buffer: &mut R
 //! #     ) -> Result<Option<Self::CustomMessage>, DecodeError> {
 //! #         unimplemented!()
@@ -156,7 +156,7 @@
 //! impl CustomMessageReader for BazHandler {
 //!     // ...
 //! #     type CustomMessage = Baz;
-//! #     fn read<R: io::Read>(
+//! #     fn read<R: LengthLimitedRead>(
 //! #         &self, _message_type: u16, _buffer: &mut R
 //! #     ) -> Result<Option<Self::CustomMessage>, DecodeError> {
 //! #         unimplemented!()
@@ -340,7 +340,7 @@ macro_rules! composite_custom_message_handler {
 
 		impl $crate::lightning::ln::wire::CustomMessageReader for $handler {
 			type CustomMessage = $message;
-			fn read<R: $crate::lightning::io::Read>(
+			fn read<R: $crate::lightning::util::ser::LengthLimitedRead>(
 				&self, message_type: u16, buffer: &mut R
 			) -> Result<Option<Self::CustomMessage>, $crate::lightning::ln::msgs::DecodeError> {
 				match message_type {

lightning-liquidity/src/lsps0/ser.rs

@@ -18,10 +18,9 @@ use crate::lsps2::msgs::{
 };
 use crate::prelude::{HashMap, String};
 
-use lightning::io;
 use lightning::ln::msgs::{DecodeError, LightningError};
 use lightning::ln::wire;
-use lightning::util::ser::{Readable, WithoutLength};
+use lightning::util::ser::{LengthLimitedRead, LengthReadable, WithoutLength};
 
 use bitcoin::secp256k1::PublicKey;
 
@@ -169,21 +168,10 @@ impl lightning::util::ser::Writeable for RawLSPSMessage {
 	}
 }
 
-impl Readable for RawLSPSMessage {
-	fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
-		// Because strings will consume the entire reader when read, they are intended to be read from a
-		// length-limiting reader. However, there's no way of knowing the length ahead of time in this
-		// case so use a wrapper.
-		struct UnknownLengthString(String);
-		impl Readable for UnknownLengthString {
-			fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
-				let v: alloc::vec::Vec<u8> = Readable::read(r)?;
-				let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
-				Ok(Self(ret))
-			}
-		}
-
-		let payload_without_length: UnknownLengthString = Readable::read(r)?;
+impl LengthReadable for RawLSPSMessage {
+	fn read_from_fixed_length_buffer<R: LengthLimitedRead>(r: &mut R) -> Result<Self, DecodeError> {
+		let payload_without_length: WithoutLength<String> =
+			LengthReadable::read_from_fixed_length_buffer(r)?;
 		Ok(Self { payload: payload_without_length.0 })
 	}
 }

lightning-liquidity/src/manager.rs

@@ -27,7 +27,7 @@ use lightning::ln::peer_handler::CustomMessageHandler;
 use lightning::ln::wire::CustomMessageReader;
 use lightning::sign::EntropySource;
 use lightning::util::logger::Level;
-use lightning::util::ser::Readable;
+use lightning::util::ser::{LengthLimitedRead, LengthReadable};
 
 use lightning_types::features::{InitFeatures, NodeFeatures};
 
@@ -449,11 +449,13 @@ where
 {
 	type CustomMessage = RawLSPSMessage;
 
-	fn read<RD: lightning::io::Read>(
+	fn read<RD: LengthLimitedRead>(
 		&self, message_type: u16, buffer: &mut RD,
 	) -> Result<Option<Self::CustomMessage>, lightning::ln::msgs::DecodeError> {
 		match message_type {
-			LSPS_MESSAGE_TYPE_ID => Ok(Some(RawLSPSMessage::read(buffer)?)),
+			LSPS_MESSAGE_TYPE_ID => {
+				Ok(Some(RawLSPSMessage::read_from_fixed_length_buffer(buffer)?))
+			},
 			_ => Ok(None),
 		}
 	}

lightning/src/ln/wire.rs

@@ -25,7 +25,7 @@ pub trait CustomMessageReader {
 	/// implementation and the message could be decoded, must return `Ok(Some(message))`. If the
 	/// message type is unknown to the implementation, must return `Ok(None)`. If a decoding error
 	/// occur, must return `Err(DecodeError::X)` where `X` details the encountered error.
-	fn read<R: io::Read>(
+	fn read<R: LengthLimitedRead>(
 		&self, message_type: u16, buffer: &mut R,
 	) -> Result<Option<Self::CustomMessage>, msgs::DecodeError>;
 }