Move things around

16 files changed, 429 insertions, 412 deletions

diff --git a/Makefile b/Makefile
index 5160725..de9a8f4 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,6 @@
 all:
-	cargo build --all-features
+	#cargo build --all-features
+	cargo build
 	cargo build --example fullmesh
 	cargo build --all-features --example basalt
 	RUST_LOG=netapp=trace,fullmesh=trace cargo run --example fullmesh -- -n 3242ce79e05e8b6a0e43441fbd140a906e13f335f298ae3a52f29784abbab500 -p 6c304114a0e1018bbe60502a34d33f4f439f370856c3333dda2726da01eb93a4894b7ef7249a71f11d342b69702f1beb7c93ec95fbcf122ad1eca583bb0629e7
diff --git a/examples/basalt.rs b/examples/basalt.rs
index 318e37c..52fab4b 100644
--- a/examples/basalt.rs
+++ b/examples/basalt.rs
@@ -14,8 +14,9 @@ use sodiumoxide::crypto::sign::ed25519;
 use tokio::sync::watch;
 
 use netapp::endpoint::*;
+use netapp::message::*;
 use netapp::peering::basalt::*;
-use netapp::proto::*;
+use netapp::send::*;
 use netapp::util::parse_peer_addr;
 use netapp::{NetApp, NodeID};
 
diff --git a/examples/fullmesh.rs b/examples/fullmesh.rs
index b068410..4ab8a8a 100644
--- a/examples/fullmesh.rs
+++ b/examples/fullmesh.rs
@@ -10,6 +10,7 @@ use sodiumoxide::crypto::sign::ed25519;
 
 use netapp::peering::fullmesh::*;
 use netapp::util::*;
+
 use netapp::NetApp;
 
 #[derive(StructOpt, Debug)]
diff --git a/src/client.rs b/src/client.rs
index 6d49f5c..663a3e4 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -5,9 +5,12 @@ use std::sync::atomic::{self, AtomicU32};
 use std::sync::{Arc, Mutex};
 
 use arc_swap::ArcSwapOption;
+use async_trait::async_trait;
 use log::{debug, error, trace};
 
 use futures::channel::mpsc::{unbounded, UnboundedReceiver};
+use futures::io::AsyncReadExt;
+use kuska_handshake::async_std::{handshake_client, BoxStream};
 use tokio::net::TcpStream;
 use tokio::select;
 use tokio::sync::{mpsc, oneshot, watch};
@@ -21,25 +24,18 @@ use opentelemetry::{
 #[cfg(feature = "telemetry")]
 use opentelemetry_contrib::trace::propagator::binary::*;
 
-use futures::io::AsyncReadExt;
-
-use async_trait::async_trait;
-
-use kuska_handshake::async_std::{handshake_client, BoxStream};
-
-use crate::endpoint::*;
 use crate::error::*;
+use crate::message::*;
 use crate::netapp::*;
-use crate::proto::*;
-use crate::proto2::*;
+use crate::recv::*;
+use crate::send::*;
 use crate::util::*;
 
 pub(crate) struct ClientConn {
 	pub(crate) remote_addr: SocketAddr,
 	pub(crate) peer_id: NodeID,
 
-	query_send:
-		ArcSwapOption<mpsc::UnboundedSender<(RequestID, RequestPriority, AssociatedStream)>>,
+	query_send: ArcSwapOption<mpsc::UnboundedSender<(RequestID, RequestPriority, ByteStream)>>,
 
 	next_query_number: AtomicU32,
 	inflight: Mutex<HashMap<RequestID, oneshot::Sender<UnboundedReceiver<Packet>>>>,
diff --git a/src/endpoint.rs b/src/endpoint.rs
index f31141d..e6b2236 100644
--- a/src/endpoint.rs
+++ b/src/endpoint.rs
@@ -5,79 +5,11 @@ use std::sync::Arc;
 use arc_swap::ArcSwapOption;
 use async_trait::async_trait;
 
-use serde::{Deserialize, Serialize};
-
 use crate::error::Error;
+use crate::message::*;
 use crate::netapp::*;
-use crate::proto::*;
 use crate::util::*;
 
-/// This trait should be implemented by all messages your application
-/// wants to handle
-pub trait Message: SerializeMessage + Send + Sync {
-	type Response: SerializeMessage + Send + Sync;
-}
-
-/// A trait for de/serializing messages, with possible associated stream.
-#[async_trait]
-pub trait SerializeMessage: Sized {
-	type SerializableSelf: Serialize + for<'de> Deserialize<'de> + Send;
-
-	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<AssociatedStream>);
-
-	// TODO should return Result
-	async fn deserialize_msg(ser_self: Self::SerializableSelf, stream: AssociatedStream) -> Self;
-}
-
-pub trait AutoSerialize: Serialize + for<'de> Deserialize<'de> + Clone + Send + Sync {}
-
-#[async_trait]
-impl<T> SerializeMessage for T
-where
-	T: AutoSerialize,
-{
-	type SerializableSelf = Self;
-	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<AssociatedStream>) {
-		(self.clone(), None)
-	}
-
-	async fn deserialize_msg(ser_self: Self::SerializableSelf, _stream: AssociatedStream) -> Self {
-		// TODO verify no stream
-		ser_self
-	}
-}
-
-impl AutoSerialize for () {}
-
-#[async_trait]
-impl<T, E> SerializeMessage for Result<T, E>
-where
-	T: SerializeMessage + Send,
-	E: SerializeMessage + Send,
-{
-	type SerializableSelf = Result<T::SerializableSelf, E::SerializableSelf>;
-
-	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<AssociatedStream>) {
-		match self {
-			Ok(ok) => {
-				let (msg, stream) = ok.serialize_msg();
-				(Ok(msg), stream)
-			}
-			Err(err) => {
-				let (msg, stream) = err.serialize_msg();
-				(Err(msg), stream)
-			}
-		}
-	}
-
-	async fn deserialize_msg(ser_self: Self::SerializableSelf, stream: AssociatedStream) -> Self {
-		match ser_self {
-			Ok(ok) => Ok(T::deserialize_msg(ok, stream).await),
-			Err(err) => Err(E::deserialize_msg(err, stream).await),
-		}
-	}
-}
-
 /// This trait should be implemented by an object of your application
 /// that can handle a message of type `M`.
 ///
@@ -191,9 +123,9 @@ pub(crate) trait GenericEndpoint {
 	async fn handle(
 		&self,
 		buf: &[u8],
-		stream: AssociatedStream,
+		stream: ByteStream,
 		from: NodeID,
-	) -> Result<(Vec<u8>, Option<AssociatedStream>), Error>;
+	) -> Result<(Vec<u8>, Option<ByteStream>), Error>;
 	fn drop_handler(&self);
 	fn clone_endpoint(&self) -> DynEndpoint;
 }
@@ -213,9 +145,9 @@ where
 	async fn handle(
 		&self,
 		buf: &[u8],
-		stream: AssociatedStream,
+		stream: ByteStream,
 		from: NodeID,
-	) -> Result<(Vec<u8>, Option<AssociatedStream>), Error> {
+	) -> Result<(Vec<u8>, Option<ByteStream>), Error> {
 		match self.0.handler.load_full() {
 			None => Err(Error::NoHandler),
 			Some(h) => {
diff --git a/src/error.rs b/src/error.rs
index 7911c29..665647c 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -1,6 +1,6 @@
-use err_derive::Error;
 use std::io;
 
+use err_derive::Error;
 use log::error;
 
 #[derive(Debug, Error)]
diff --git a/src/lib.rs b/src/lib.rs
index cb24337..1edb919 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -17,10 +17,11 @@ pub mod error;
 pub mod util;
 
 pub mod endpoint;
-pub mod proto;
+pub mod message;
 
 mod client;
-mod proto2;
+mod recv;
+mod send;
 mod server;
 
 pub mod netapp;
diff --git a/src/message.rs b/src/message.rs
new file mode 100644
index 0000000..dbcc857
--- /dev/null
+++ b/src/message.rs
@@ -0,0 +1,255 @@
+use async_trait::async_trait;
+use futures::stream::{Stream, StreamExt};
+use serde::{Deserialize, Serialize};
+
+use crate::error::*;
+use crate::util::*;
+
+/// Priority of a request (click to read more about priorities).
+///
+/// This priority value is used to priorize messages
+/// in the send queue of the client, and their responses in the send queue of the
+/// server. Lower values mean higher priority.
+///
+/// This mechanism is usefull for messages bigger than the maximum chunk size
+/// (set at `0x4000` bytes), such as large file transfers.
+/// In such case, all of the messages in the send queue with the highest priority
+/// will take turns to send individual chunks, in a round-robin fashion.
+/// Once all highest priority messages are sent successfully, the messages with
+/// the next highest priority will begin being sent in the same way.
+///
+/// The same priority value is given to a request and to its associated response.
+pub type RequestPriority = u8;
+
+/// Priority class: high
+pub const PRIO_HIGH: RequestPriority = 0x20;
+/// Priority class: normal
+pub const PRIO_NORMAL: RequestPriority = 0x40;
+/// Priority class: background
+pub const PRIO_BACKGROUND: RequestPriority = 0x80;
+/// Priority: primary among given class
+pub const PRIO_PRIMARY: RequestPriority = 0x00;
+/// Priority: secondary among given class (ex: `PRIO_HIGH | PRIO_SECONDARY`)
+pub const PRIO_SECONDARY: RequestPriority = 0x01;
+
+// ----
+
+/// This trait should be implemented by all messages your application
+/// wants to handle
+pub trait Message: SerializeMessage + Send + Sync {
+	type Response: SerializeMessage + Send + Sync;
+}
+
+/// A trait for de/serializing messages, with possible associated stream.
+#[async_trait]
+pub trait SerializeMessage: Sized {
+	type SerializableSelf: Serialize + for<'de> Deserialize<'de> + Send;
+
+	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<ByteStream>);
+
+	// TODO should return Result
+	async fn deserialize_msg(ser_self: Self::SerializableSelf, stream: ByteStream) -> Self;
+}
+
+pub trait AutoSerialize: Serialize + for<'de> Deserialize<'de> + Clone + Send + Sync {}
+
+#[async_trait]
+impl<T> SerializeMessage for T
+where
+	T: AutoSerialize,
+{
+	type SerializableSelf = Self;
+	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<ByteStream>) {
+		(self.clone(), None)
+	}
+
+	async fn deserialize_msg(ser_self: Self::SerializableSelf, _stream: ByteStream) -> Self {
+		// TODO verify no stream
+		ser_self
+	}
+}
+
+impl AutoSerialize for () {}
+
+#[async_trait]
+impl<T, E> SerializeMessage for Result<T, E>
+where
+	T: SerializeMessage + Send,
+	E: SerializeMessage + Send,
+{
+	type SerializableSelf = Result<T::SerializableSelf, E::SerializableSelf>;
+
+	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<ByteStream>) {
+		match self {
+			Ok(ok) => {
+				let (msg, stream) = ok.serialize_msg();
+				(Ok(msg), stream)
+			}
+			Err(err) => {
+				let (msg, stream) = err.serialize_msg();
+				(Err(msg), stream)
+			}
+		}
+	}
+
+	async fn deserialize_msg(ser_self: Self::SerializableSelf, stream: ByteStream) -> Self {
+		match ser_self {
+			Ok(ok) => Ok(T::deserialize_msg(ok, stream).await),
+			Err(err) => Err(E::deserialize_msg(err, stream).await),
+		}
+	}
+}
+
+// ----
+
+pub(crate) struct QueryMessage<'a> {
+	pub(crate) prio: RequestPriority,
+	pub(crate) path: &'a [u8],
+	pub(crate) telemetry_id: Option<Vec<u8>>,
+	pub(crate) body: &'a [u8],
+}
+
+/// QueryMessage encoding:
+/// - priority: u8
+/// - path length: u8
+/// - path: [u8; path length]
+/// - telemetry id length: u8
+/// - telemetry id: [u8; telemetry id length]
+/// - body [u8; ..]
+impl<'a> QueryMessage<'a> {
+	pub(crate) fn encode(self) -> Vec<u8> {
+		let tel_len = match &self.telemetry_id {
+			Some(t) => t.len(),
+			None => 0,
+		};
+
+		let mut ret = Vec::with_capacity(10 + self.path.len() + tel_len + self.body.len());
+
+		ret.push(self.prio);
+
+		ret.push(self.path.len() as u8);
+		ret.extend_from_slice(self.path);
+
+		if let Some(t) = self.telemetry_id {
+			ret.push(t.len() as u8);
+			ret.extend(t);
+		} else {
+			ret.push(0u8);
+		}
+
+		ret.extend_from_slice(self.body);
+
+		ret
+	}
+
+	pub(crate) fn decode(bytes: &'a [u8]) -> Result<Self, Error> {
+		if bytes.len() < 3 {
+			return Err(Error::Message("Invalid protocol message".into()));
+		}
+
+		let path_length = bytes[1] as usize;
+		if bytes.len() < 3 + path_length {
+			return Err(Error::Message("Invalid protocol message".into()));
+		}
+
+		let telemetry_id_len = bytes[2 + path_length] as usize;
+		if bytes.len() < 3 + path_length + telemetry_id_len {
+			return Err(Error::Message("Invalid protocol message".into()));
+		}
+
+		let path = &bytes[2..2 + path_length];
+		let telemetry_id = if telemetry_id_len > 0 {
+			Some(bytes[3 + path_length..3 + path_length + telemetry_id_len].to_vec())
+		} else {
+			None
+		};
+
+		let body = &bytes[3 + path_length + telemetry_id_len..];
+
+		Ok(Self {
+			prio: bytes[0],
+			path,
+			telemetry_id,
+			body,
+		})
+	}
+}
+
+pub(crate) struct Framing {
+	direct: Vec<u8>,
+	stream: Option<ByteStream>,
+}
+
+impl Framing {
+	pub fn new(direct: Vec<u8>, stream: Option<ByteStream>) -> Self {
+		assert!(direct.len() <= u32::MAX as usize);
+		Framing { direct, stream }
+	}
+
+	pub fn into_stream(self) -> ByteStream {
+		use futures::stream;
+		let len = self.direct.len() as u32;
+		// required because otherwise the borrow-checker complains
+		let Framing { direct, stream } = self;
+
+		let res = stream::once(async move { Ok(u32::to_be_bytes(len).to_vec()) })
+			.chain(stream::once(async move { Ok(direct) }));
+
+		if let Some(stream) = stream {
+			Box::pin(res.chain(stream))
+		} else {
+			Box::pin(res)
+		}
+	}
+
+	pub async fn from_stream<S: Stream<Item = Packet> + Unpin + Send + 'static>(
+		mut stream: S,
+	) -> Result<Self, Error> {
+		let mut packet = stream
+			.next()
+			.await
+			.ok_or(Error::Framing)?
+			.map_err(|_| Error::Framing)?;
+		if packet.len() < 4 {
+			return Err(Error::Framing);
+		}
+
+		let mut len = [0; 4];
+		len.copy_from_slice(&packet[..4]);
+		let len = u32::from_be_bytes(len);
+		packet.drain(..4);
+
+		let mut buffer = Vec::new();
+		let len = len as usize;
+		loop {
+			let max_cp = std::cmp::min(len - buffer.len(), packet.len());
+
+			buffer.extend_from_slice(&packet[..max_cp]);
+			if buffer.len() == len {
+				packet.drain(..max_cp);
+				break;
+			}
+			packet = stream
+				.next()
+				.await
+				.ok_or(Error::Framing)?
+				.map_err(|_| Error::Framing)?;
+		}
+
+		let stream: ByteStream = if packet.is_empty() {
+			Box::pin(stream)
+		} else {
+			Box::pin(futures::stream::once(async move { Ok(packet) }).chain(stream))
+		};
+
+		Ok(Framing {
+			direct: buffer,
+			stream: Some(stream),
+		})
+	}
+
+	pub fn into_parts(self) -> (Vec<u8>, ByteStream) {
+		let Framing { direct, stream } = self;
+		(direct, stream.unwrap_or(Box::pin(futures::stream::empty())))
+	}
+}
diff --git a/src/netapp.rs b/src/netapp.rs
index 27f17e6..dd22d90 100644
--- a/src/netapp.rs
+++ b/src/netapp.rs
@@ -20,7 +20,7 @@ use tokio::sync::{mpsc, watch};
 use crate::client::*;
 use crate::endpoint::*;
 use crate::error::*;
-use crate::proto::*;
+use crate::message::*;
 use crate::server::*;
 use crate::util::*;
 
diff --git a/src/peering/basalt.rs b/src/peering/basalt.rs
index 7f77995..98977a3 100644
--- a/src/peering/basalt.rs
+++ b/src/peering/basalt.rs
@@ -14,8 +14,9 @@ use sodiumoxide::crypto::hash;
 use tokio::sync::watch;
 
 use crate::endpoint::*;
+use crate::message::*;
 use crate::netapp::*;
-use crate::proto::*;
+use crate::send::*;
 use crate::NodeID;
 
 // -- Protocol messages --
diff --git a/src/peering/fullmesh.rs b/src/peering/fullmesh.rs
index 7dfc5c4..5b489ae 100644
--- a/src/peering/fullmesh.rs
+++ b/src/peering/fullmesh.rs
@@ -17,7 +17,8 @@ use sodiumoxide::crypto::hash;
 use crate::endpoint::*;
 use crate::error::*;
 use crate::netapp::*;
-use crate::proto::*;
+
+use crate::message::*;
 use crate::NodeID;
 
 const CONN_RETRY_INTERVAL: Duration = Duration::from_secs(30);
diff --git a/src/proto2.rs b/src/proto2.rs
deleted file mode 100644
index 7210781..0000000
--- a/src/proto2.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-use crate::error::*;
-use crate::proto::*;
-
-pub(crate) struct QueryMessage<'a> {
-	pub(crate) prio: RequestPriority,
-	pub(crate) path: &'a [u8],
-	pub(crate) telemetry_id: Option<Vec<u8>>,
-	pub(crate) body: &'a [u8],
-}
-
-/// QueryMessage encoding:
-/// - priority: u8
-/// - path length: u8
-/// - path: [u8; path length]
-/// - telemetry id length: u8
-/// - telemetry id: [u8; telemetry id length]
-/// - body [u8; ..]
-impl<'a> QueryMessage<'a> {
-	pub(crate) fn encode(self) -> Vec<u8> {
-		let tel_len = match &self.telemetry_id {
-			Some(t) => t.len(),
-			None => 0,
-		};
-
-		let mut ret = Vec::with_capacity(10 + self.path.len() + tel_len + self.body.len());
-
-		ret.push(self.prio);
-
-		ret.push(self.path.len() as u8);
-		ret.extend_from_slice(self.path);
-
-		if let Some(t) = self.telemetry_id {
-			ret.push(t.len() as u8);
-			ret.extend(t);
-		} else {
-			ret.push(0u8);
-		}
-
-		ret.extend_from_slice(self.body);
-
-		ret
-	}
-
-	pub(crate) fn decode(bytes: &'a [u8]) -> Result<Self, Error> {
-		if bytes.len() < 3 {
-			return Err(Error::Message("Invalid protocol message".into()));
-		}
-
-		let path_length = bytes[1] as usize;
-		if bytes.len() < 3 + path_length {
-			return Err(Error::Message("Invalid protocol message".into()));
-		}
-
-		let telemetry_id_len = bytes[2 + path_length] as usize;
-		if bytes.len() < 3 + path_length + telemetry_id_len {
-			return Err(Error::Message("Invalid protocol message".into()));
-		}
-
-		let path = &bytes[2..2 + path_length];
-		let telemetry_id = if telemetry_id_len > 0 {
-			Some(bytes[3 + path_length..3 + path_length + telemetry_id_len].to_vec())
-		} else {
-			None
-		};
-
-		let body = &bytes[3 + path_length + telemetry_id_len..];
-
-		Ok(Self {
-			prio: bytes[0],
-			path,
-			telemetry_id,
-			body,
-		})
-	}
-}
diff --git a/src/recv.rs b/src/recv.rs
new file mode 100644
index 0000000..628612b
--- /dev/null
+++ b/src/recv.rs
@@ -0,0 +1,114 @@
+use std::collections::HashMap;
+
+use std::sync::Arc;
+
+use log::trace;
+
+use futures::channel::mpsc::{unbounded, UnboundedReceiver, UnboundedSender};
+use futures::AsyncReadExt;
+
+use async_trait::async_trait;
+
+use crate::error::*;
+
+use crate::send::*;
+use crate::util::Packet;
+
+/// Structure to warn when the sender is dropped before end of stream was reached, like when
+/// connection to some remote drops while transmitting data
+struct Sender {
+	inner: UnboundedSender<Packet>,
+	closed: bool,
+}
+
+impl Sender {
+	fn new(inner: UnboundedSender<Packet>) -> Self {
+		Sender {
+			inner,
+			closed: false,
+		}
+	}
+
+	fn send(&self, packet: Packet) {
+		let _ = self.inner.unbounded_send(packet);
+	}
+
+	fn end(&mut self) {
+		self.closed = true;
+	}
+}
+
+impl Drop for Sender {
+	fn drop(&mut self) {
+		if !self.closed {
+			self.send(Err(255));
+		}
+		self.inner.close_channel();
+	}
+}
+
+/// The RecvLoop trait, which is implemented both by the client and the server
+/// connection objects (ServerConn and ClientConn) adds a method `.recv_loop()`
+/// and a prototype of a handler for received messages `.recv_handler()` that
+/// must be filled by implementors. `.recv_loop()` receives messages in a loop
+/// according to the protocol defined above: chunks of message in progress of being
+/// received are stored in a buffer, and when the last chunk of a message is received,
+/// the full message is passed to the receive handler.
+#[async_trait]
+pub(crate) trait RecvLoop: Sync + 'static {
+	fn recv_handler(self: &Arc<Self>, id: RequestID, stream: UnboundedReceiver<Packet>);
+
+	async fn recv_loop<R>(self: Arc<Self>, mut read: R) -> Result<(), Error>
+	where
+		R: AsyncReadExt + Unpin + Send + Sync,
+	{
+		let mut streams: HashMap<RequestID, Sender> = HashMap::new();
+		loop {
+			trace!("recv_loop: reading packet");
+			let mut header_id = [0u8; RequestID::BITS as usize / 8];
+			match read.read_exact(&mut header_id[..]).await {
+				Ok(_) => (),
+				Err(e) if e.kind() == std::io::ErrorKind::UnexpectedEof => break,
+				Err(e) => return Err(e.into()),
+			};
+			let id = RequestID::from_be_bytes(header_id);
+			trace!("recv_loop: got header id: {:04x}", id);
+
+			let mut header_size = [0u8; ChunkLength::BITS as usize / 8];
+			read.read_exact(&mut header_size[..]).await?;
+			let size = ChunkLength::from_be_bytes(header_size);
+			trace!("recv_loop: got header size: {:04x}", size);
+
+			let has_cont = (size & CHUNK_HAS_CONTINUATION) != 0;
+			let is_error = (size & ERROR_MARKER) != 0;
+			let packet = if is_error {
+				Err(size as u8)
+			} else {
+				let size = size & !CHUNK_HAS_CONTINUATION;
+				let mut next_slice = vec![0; size as usize];
+				read.read_exact(&mut next_slice[..]).await?;
+				trace!("recv_loop: read {} bytes", next_slice.len());
+				Ok(next_slice)
+			};
+
+			let mut sender = if let Some(send) = streams.remove(&(id)) {
+				send
+			} else {
+				let (send, recv) = unbounded();
+				self.recv_handler(id, recv);
+				Sender::new(send)
+			};
+
+			// if we get an error, the receiving end is disconnected. We still need to
+			// reach eos before dropping this sender
+			sender.send(packet);
+
+			if has_cont {
+				streams.insert(id, sender);
+			} else {
+				sender.end();
+			}
+		}
+		Ok(())
+	}
+}
diff --git a/src/proto.rs b/src/send.rs
index 92d8d80..330d41d 100644
--- a/src/proto.rs
+++ b/src/send.rs
@@ -1,48 +1,19 @@
-use std::collections::{HashMap, VecDeque};
+use std::collections::VecDeque;
 use std::pin::Pin;
 use std::sync::Arc;
 use std::task::{Context, Poll};
 
+use async_trait::async_trait;
 use log::trace;
 
-use futures::channel::mpsc::{unbounded, UnboundedReceiver, UnboundedSender};
-use futures::{AsyncReadExt, AsyncWriteExt};
-use futures::{Stream, StreamExt};
+use futures::AsyncWriteExt;
+use futures::Stream;
 use kuska_handshake::async_std::BoxStreamWrite;
-
 use tokio::sync::mpsc;
 
-use async_trait::async_trait;
-
 use crate::error::*;
-use crate::util::{AssociatedStream, Packet};
-
-/// Priority of a request (click to read more about priorities).
-///
-/// This priority value is used to priorize messages
-/// in the send queue of the client, and their responses in the send queue of the
-/// server. Lower values mean higher priority.
-///
-/// This mechanism is usefull for messages bigger than the maximum chunk size
-/// (set at `0x4000` bytes), such as large file transfers.
-/// In such case, all of the messages in the send queue with the highest priority
-/// will take turns to send individual chunks, in a round-robin fashion.
-/// Once all highest priority messages are sent successfully, the messages with
-/// the next highest priority will begin being sent in the same way.
-///
-/// The same priority value is given to a request and to its associated response.
-pub type RequestPriority = u8;
-
-/// Priority class: high
-pub const PRIO_HIGH: RequestPriority = 0x20;
-/// Priority class: normal
-pub const PRIO_NORMAL: RequestPriority = 0x40;
-/// Priority class: background
-pub const PRIO_BACKGROUND: RequestPriority = 0x80;
-/// Priority: primary among given class
-pub const PRIO_PRIMARY: RequestPriority = 0x00;
-/// Priority: secondary among given class (ex: `PRIO_HIGH | PRIO_SECONDARY`)
-pub const PRIO_SECONDARY: RequestPriority = 0x01;
+use crate::message::*;
+use crate::util::{ByteStream, Packet};
 
 // Messages are sent by chunks
 // Chunk format:
@@ -52,10 +23,10 @@ pub const PRIO_SECONDARY: RequestPriority = 0x01;
 // - [u8; chunk_length] chunk data
 
 pub(crate) type RequestID = u32;
-type ChunkLength = u16;
-const MAX_CHUNK_LENGTH: ChunkLength = 0x3FF0;
-const ERROR_MARKER: ChunkLength = 0x4000;
-const CHUNK_HAS_CONTINUATION: ChunkLength = 0x8000;
+pub(crate) type ChunkLength = u16;
+pub(crate) const MAX_CHUNK_LENGTH: ChunkLength = 0x3FF0;
+pub(crate) const ERROR_MARKER: ChunkLength = 0x4000;
+pub(crate) const CHUNK_HAS_CONTINUATION: ChunkLength = 0x8000;
 
 struct SendQueueItem {
 	id: RequestID,
@@ -66,15 +37,15 @@ struct SendQueueItem {
 #[pin_project::pin_project]
 struct DataReader {
 	#[pin]
-	reader: AssociatedStream,
+	reader: ByteStream,
 	packet: Packet,
 	pos: usize,
 	buf: Vec<u8>,
 	eos: bool,
 }
 
-impl From<AssociatedStream> for DataReader {
-	fn from(data: AssociatedStream) -> DataReader {
+impl From<ByteStream> for DataReader {
+	fn from(data: ByteStream) -> DataReader {
 		DataReader {
 			reader: data,
 			packet: Ok(Vec::new()),
@@ -297,7 +268,7 @@ impl<'a> futures::Future for SendQueuePollNextReady<'a> {
 pub(crate) trait SendLoop: Sync {
 	async fn send_loop<W>(
 		self: Arc<Self>,
-		mut msg_recv: mpsc::UnboundedReceiver<(RequestID, RequestPriority, AssociatedStream)>,
+		mut msg_recv: mpsc::UnboundedReceiver<(RequestID, RequestPriority, ByteStream)>,
 		mut write: BoxStreamWrite<W>,
 	) -> Result<(), Error>
 	where
@@ -343,184 +314,6 @@ pub(crate) trait SendLoop: Sync {
 	}
 }
 
-pub(crate) struct Framing {
-	direct: Vec<u8>,
-	stream: Option<AssociatedStream>,
-}
-
-impl Framing {
-	pub fn new(direct: Vec<u8>, stream: Option<AssociatedStream>) -> Self {
-		assert!(direct.len() <= u32::MAX as usize);
-		Framing { direct, stream }
-	}
-
-	pub fn into_stream(self) -> AssociatedStream {
-		use futures::stream;
-		let len = self.direct.len() as u32;
-		// required because otherwise the borrow-checker complains
-		let Framing { direct, stream } = self;
-
-		let res = stream::once(async move { Ok(u32::to_be_bytes(len).to_vec()) })
-			.chain(stream::once(async move { Ok(direct) }));
-
-		if let Some(stream) = stream {
-			Box::pin(res.chain(stream))
-		} else {
-			Box::pin(res)
-		}
-	}
-
-	pub async fn from_stream<S: Stream<Item = Packet> + Unpin + Send + 'static>(
-		mut stream: S,
-	) -> Result<Self, Error> {
-		let mut packet = stream
-			.next()
-			.await
-			.ok_or(Error::Framing)?
-			.map_err(|_| Error::Framing)?;
-		if packet.len() < 4 {
-			return Err(Error::Framing);
-		}
-
-		let mut len = [0; 4];
-		len.copy_from_slice(&packet[..4]);
-		let len = u32::from_be_bytes(len);
-		packet.drain(..4);
-
-		let mut buffer = Vec::new();
-		let len = len as usize;
-		loop {
-			let max_cp = std::cmp::min(len - buffer.len(), packet.len());
-
-			buffer.extend_from_slice(&packet[..max_cp]);
-			if buffer.len() == len {
-				packet.drain(..max_cp);
-				break;
-			}
-			packet = stream
-				.next()
-				.await
-				.ok_or(Error::Framing)?
-				.map_err(|_| Error::Framing)?;
-		}
-
-		let stream: AssociatedStream = if packet.is_empty() {
-			Box::pin(stream)
-		} else {
-			Box::pin(futures::stream::once(async move { Ok(packet) }).chain(stream))
-		};
-
-		Ok(Framing {
-			direct: buffer,
-			stream: Some(stream),
-		})
-	}
-
-	pub fn into_parts(self) -> (Vec<u8>, AssociatedStream) {
-		let Framing { direct, stream } = self;
-		(direct, stream.unwrap_or(Box::pin(futures::stream::empty())))
-	}
-}
-
-/// Structure to warn when the sender is dropped before end of stream was reached, like when
-/// connection to some remote drops while transmitting data
-struct Sender {
-	inner: UnboundedSender<Packet>,
-	closed: bool,
-}
-
-impl Sender {
-	fn new(inner: UnboundedSender<Packet>) -> Self {
-		Sender {
-			inner,
-			closed: false,
-		}
-	}
-
-	fn send(&self, packet: Packet) {
-		let _ = self.inner.unbounded_send(packet);
-	}
-
-	fn end(&mut self) {
-		self.closed = true;
-	}
-}
-
-impl Drop for Sender {
-	fn drop(&mut self) {
-		if !self.closed {
-			self.send(Err(255));
-		}
-		self.inner.close_channel();
-	}
-}
-
-/// The RecvLoop trait, which is implemented both by the client and the server
-/// connection objects (ServerConn and ClientConn) adds a method `.recv_loop()`
-/// and a prototype of a handler for received messages `.recv_handler()` that
-/// must be filled by implementors. `.recv_loop()` receives messages in a loop
-/// according to the protocol defined above: chunks of message in progress of being
-/// received are stored in a buffer, and when the last chunk of a message is received,
-/// the full message is passed to the receive handler.
-#[async_trait]
-pub(crate) trait RecvLoop: Sync + 'static {
-	fn recv_handler(self: &Arc<Self>, id: RequestID, stream: UnboundedReceiver<Packet>);
-
-	async fn recv_loop<R>(self: Arc<Self>, mut read: R) -> Result<(), Error>
-	where
-		R: AsyncReadExt + Unpin + Send + Sync,
-	{
-		let mut streams: HashMap<RequestID, Sender> = HashMap::new();
-		loop {
-			trace!("recv_loop: reading packet");
-			let mut header_id = [0u8; RequestID::BITS as usize / 8];
-			match read.read_exact(&mut header_id[..]).await {
-				Ok(_) => (),
-				Err(e) if e.kind() == std::io::ErrorKind::UnexpectedEof => break,
-				Err(e) => return Err(e.into()),
-			};
-			let id = RequestID::from_be_bytes(header_id);
-			trace!("recv_loop: got header id: {:04x}", id);
-
-			let mut header_size = [0u8; ChunkLength::BITS as usize / 8];
-			read.read_exact(&mut header_size[..]).await?;
-			let size = ChunkLength::from_be_bytes(header_size);
-			trace!("recv_loop: got header size: {:04x}", size);
-
-			let has_cont = (size & CHUNK_HAS_CONTINUATION) != 0;
-			let is_error = (size & ERROR_MARKER) != 0;
-			let packet = if is_error {
-				Err(size as u8)
-			} else {
-				let size = size & !CHUNK_HAS_CONTINUATION;
-				let mut next_slice = vec![0; size as usize];
-				read.read_exact(&mut next_slice[..]).await?;
-				trace!("recv_loop: read {} bytes", next_slice.len());
-				Ok(next_slice)
-			};
-
-			let mut sender = if let Some(send) = streams.remove(&(id)) {
-				send
-			} else {
-				let (send, recv) = unbounded();
-				self.recv_handler(id, recv);
-				Sender::new(send)
-			};
-
-			// if we get an error, the receiving end is disconnected. We still need to
-			// reach eos before dropping this sender
-			sender.send(packet);
-
-			if has_cont {
-				streams.insert(id, sender);
-			} else {
-				sender.end();
-			}
-		}
-		Ok(())
-	}
-}
-
 #[cfg(test)]
 mod test {
 	use super::*;
diff --git a/src/server.rs b/src/server.rs
index 8075484..1f1c22a 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -2,8 +2,17 @@ use std::net::SocketAddr;
 use std::sync::Arc;
 
 use arc_swap::ArcSwapOption;
+use async_trait::async_trait;
 use log::{debug, trace};
 
+use futures::channel::mpsc::UnboundedReceiver;
+use futures::io::{AsyncReadExt, AsyncWriteExt};
+use kuska_handshake::async_std::{handshake_server, BoxStream};
+use tokio::net::TcpStream;
+use tokio::select;
+use tokio::sync::{mpsc, watch};
+use tokio_util::compat::*;
+
 #[cfg(feature = "telemetry")]
 use opentelemetry::{
 	trace::{FutureExt, Span, SpanKind, TraceContextExt, TraceId, Tracer},
@@ -14,22 +23,11 @@ use opentelemetry_contrib::trace::propagator::binary::*;
 #[cfg(feature = "telemetry")]
 use rand::{thread_rng, Rng};
 
-use tokio::net::TcpStream;
-use tokio::select;
-use tokio::sync::{mpsc, watch};
-use tokio_util::compat::*;
-
-use futures::channel::mpsc::UnboundedReceiver;
-use futures::io::{AsyncReadExt, AsyncWriteExt};
-
-use async_trait::async_trait;
-
-use kuska_handshake::async_std::{handshake_server, BoxStream};
-
 use crate::error::*;
+use crate::message::*;
 use crate::netapp::*;
-use crate::proto::*;
-use crate::proto2::*;
+use crate::recv::*;
+use crate::send::*;
 use crate::util::*;
 
 // The client and server connection structs (client.rs and server.rs)
@@ -55,7 +53,7 @@ pub(crate) struct ServerConn {
 
 	netapp: Arc<NetApp>,
 
-	resp_send: ArcSwapOption<mpsc::UnboundedSender<(RequestID, RequestPriority, AssociatedStream)>>,
+	resp_send: ArcSwapOption<mpsc::UnboundedSender<(RequestID, RequestPriority, ByteStream)>>,
 }
 
 impl ServerConn {
@@ -126,8 +124,8 @@ impl ServerConn {
 	async fn recv_handler_aux(
 		self: &Arc<Self>,
 		bytes: &[u8],
-		stream: AssociatedStream,
-	) -> Result<(Vec<u8>, Option<AssociatedStream>), Error> {
+		stream: ByteStream,
+	) -> Result<(Vec<u8>, Option<ByteStream>), Error> {
 		let msg = QueryMessage::decode(bytes)?;
 		let path = String::from_utf8(msg.path.to_vec())?;
 
diff --git a/src/util.rs b/src/util.rs
index 186678d..6fbafe6 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -1,17 +1,15 @@
-use crate::endpoint::SerializeMessage;
-
 use std::net::SocketAddr;
 use std::net::ToSocketAddrs;
 use std::pin::Pin;
 
-use futures::Stream;
-
 use log::info;
-
 use serde::Serialize;
 
+use futures::Stream;
 use tokio::sync::watch;
 
+use crate::message::SerializeMessage;
+
 /// A node's identifier, which is also its public cryptographic key
 pub type NodeID = sodiumoxide::crypto::sign::ed25519::PublicKey;
 /// A node's secret key
@@ -27,7 +25,7 @@ pub type NetworkKey = sodiumoxide::crypto::auth::Key;
 ///
 /// Error code 255 means the stream was cut before its end. Other codes have no predefined
 /// meaning, it's up to your application to define their semantic.
-pub type AssociatedStream = Pin<Box<dyn Stream<Item = Packet> + Send>>;
+pub type ByteStream = Pin<Box<dyn Stream<Item = Packet> + Send>>;
 
 pub type Packet = Result<Vec<u8>, u8>;
 
@@ -38,7 +36,7 @@ pub type Packet = Result<Vec<u8>, u8>;
 /// This is used internally by the netapp communication protocol.
 pub fn rmp_to_vec_all_named<T>(
 	val: &T,
-) -> Result<(Vec<u8>, Option<AssociatedStream>), rmp_serde::encode::Error>
+) -> Result<(Vec<u8>, Option<ByteStream>), rmp_serde::encode::Error>
 where
 	T: SerializeMessage + ?Sized,
 {