[WIP] Rate Limiting (#57)

* Setup tests for rate limiting
* Add send and receive rate configs to P2P Config
* Setup ThrottledConnection and ThrottledWrite
* Add Tokio io
* Fix ThrottledReader + Add Bytes
* Attach Rate Limiting to Connection

p2p/Cargo.toml

@@ -13,8 +13,10 @@ net2 = "0.2.0"
 rand = "^0.3"
 serde = "~1.0.8"
 serde_derive = "~1.0.8"
+bytes = "0.4.3"
 tokio-core="^0.1.1"
 tokio-timer="^0.1.0"
+tokio-io="^0.1"
 time = "^0.1"
 enum_primitive = "^0.1.0"
 num = "^0.1.36"

p2p/src/conn.rs

@@ -24,14 +24,16 @@ use futures;
 use futures::{Stream, Future};
 use futures::stream;
 use futures::sync::mpsc::{Sender, UnboundedSender, UnboundedReceiver};
-use tokio_core::io::{Io, WriteHalf, ReadHalf, write_all, read_exact};
+use tokio_core::io::{WriteHalf, ReadHalf, write_all, read_exact};
 use tokio_core::net::TcpStream;
 use tokio_timer::{Timer, TimerError};
+use tokio_io::*;
 
 use core::core::hash::{Hash, ZERO_HASH};
 use core::ser;
 use msg::*;
 use types::Error;
+use rate_limit::*;
 
 /// Handler to provide to the connection, will be called back anytime a message
 /// is received. The provided sender can be use to immediately send back
@@ -92,6 +94,11 @@ impl Connection {
 
 		let (reader, writer) = conn.split();
 
+		// Set Max Read to 12 Mb/s
+		let reader = ThrottledReader::new(reader, 12_000_000);
+		// Set Max Write to 12 Mb/s
+		let writer = ThrottledWriter::new(writer, 12_000_000);
+
 		// prepare the channel that will transmit data to the connection writer
 		let (tx, rx) = futures::sync::mpsc::unbounded();
 
@@ -125,10 +132,12 @@ impl Connection {
 
 	/// Prepares the future that gets message data produced by our system and
 	/// sends it to the peer connection
-	fn write_msg(&self,
-	             rx: UnboundedReceiver<Vec<u8>>,
-	             writer: WriteHalf<TcpStream>)
-	             -> Box<Future<Item = WriteHalf<TcpStream>, Error = Error>> {
+	fn write_msg<W>(&self,
+	                rx: UnboundedReceiver<Vec<u8>>,
+	                writer: W)
+	                -> Box<Future<Item = W, Error = Error>>
+		where W: AsyncWrite + 'static
+	{
 
 		let sent_bytes = self.sent_bytes.clone();
 		let send_data = rx
@@ -148,12 +157,13 @@ impl Connection {
 
 	/// Prepares the future reading from the peer connection, parsing each
 	/// message and forwarding them appropriately based on their type
-	fn read_msg<F>(&self,
-	               sender: UnboundedSender<Vec<u8>>,
-	               reader: ReadHalf<TcpStream>,
-	               handler: F)
-	               -> Box<Future<Item = ReadHalf<TcpStream>, Error = Error>>
-		where F: Handler + 'static
+	fn read_msg<F, R>(&self,
+	                  sender: UnboundedSender<Vec<u8>>,
+	                  reader: R,
+	                  handler: F)
+	                  -> Box<Future<Item = R, Error = Error>>
+		where F: Handler + 'static,
+		      R: AsyncRead + 'static
 	{
 
 		// infinite iterator stream so we repeat the message reading logic until the

p2p/src/lib.rs

@@ -33,6 +33,8 @@ extern crate log;
 extern crate futures;
 #[macro_use]
 extern crate tokio_core;
+extern crate tokio_io;
+extern crate bytes;
 extern crate tokio_timer;
 extern crate rand;
 extern crate serde;
@@ -43,6 +45,7 @@ extern crate num;
 
 mod conn;
 pub mod handshake;
+mod rate_limit;
 mod msg;
 mod peer;
 mod protocol;

p2p/src/peer.rs

@@ -52,10 +52,10 @@ impl Peer {
 			.and_then(|(conn, proto, info)| {
 				Ok((conn,
 				    Peer {
-					info: info,
-					proto: Box::new(proto),
-					state: Arc::new(RwLock::new(State::Connected)),
-				}))
+					    info: info,
+					    proto: Box::new(proto),
+					    state: Arc::new(RwLock::new(State::Connected)),
+				    }))
 			});
 		Box::new(connect_peer)
 	}
@@ -70,10 +70,10 @@ impl Peer {
 			.and_then(|(conn, proto, info)| {
 				Ok((conn,
 				    Peer {
-					info: info,
-					proto: Box::new(proto),
-					state: Arc::new(RwLock::new(State::Connected)),
-				}))
+					    info: info,
+					    proto: Box::new(proto),
+					    state: Arc::new(RwLock::new(State::Connected)),
+				    }))
 			});
 		Box::new(hs_peer)
 	}

p2p/src/rate_limit.rs

@@ -0,0 +1,190 @@
+// Copyright 2016 The Grin Developers
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Provides wrappers for throttling readers and writers
+
+use std::time::{Instant, Duration};
+use std::io;
+
+use futures::*;
+use tokio_io::*;
+use bytes::{Buf, BytesMut, BufMut};
+
+/// A Rate Limited Reader
+#[derive(Debug)]
+pub struct ThrottledReader<R: AsyncRead> {
+	reader: R,
+	/// Max Bytes per second
+	max: u32,
+	/// Stores a count of last request and last request time
+	allowed: isize,
+	last_check: Instant,
+}
+
+impl<R: AsyncRead> ThrottledReader<R> {
+	/// Adds throttling to a reader.
+	/// The resulting reader will read at most `max` amount of bytes per second
+	pub fn new(reader: R, max: u32) -> Self {
+		ThrottledReader {
+			reader: reader,
+			max: max,
+			allowed: max as isize,
+			last_check: Instant::now(),
+		}
+	}
+
+	/// Get a shared reference to the inner sink.
+	pub fn get_ref(&self) -> &R {
+		&self.reader
+	}
+
+	/// Get a mutable reference to the inner sink.
+	pub fn get_mut(&mut self) -> &mut R {
+		&mut self.reader
+	}
+
+	/// Consumes this combinator, returning the underlying sink.
+	///
+	/// Note that this may discard intermediate state of this combinator, so
+	/// care should be taken to avoid losing resources when this is called.
+	pub fn into_inner(self) -> R {
+		self.reader
+	}
+}
+
+impl<R: AsyncRead> io::Read for ThrottledReader<R> {
+	fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+		self.reader.read(buf)
+	}
+}
+
+impl<R: AsyncRead> AsyncRead for ThrottledReader<R> {
+	unsafe fn prepare_uninitialized_buffer(&self, buf: &mut [u8]) -> bool {
+		self.reader.prepare_uninitialized_buffer(buf)
+	}
+
+	fn read_buf<B: BufMut>(&mut self, buf: &mut B) -> Poll<usize, io::Error> {
+		// Check passed Time
+		let time_passed = self.last_check.elapsed();
+		self.last_check = Instant::now();
+		self.allowed += time_passed.as_secs() as isize * self.max as isize;
+
+		// Throttle
+		if self.allowed > self.max as isize {
+			self.allowed = self.max as isize;
+		}
+
+		// Check if Allowed
+		if self.allowed < 1 {
+			return Ok(Async::NotReady);
+		}
+
+		// Since we can't limit the scope that is read,
+		// we use a signed `allowed` counter in case n > allowed
+		let res = self.reader.read_buf(buf);
+
+		// Decrement Allowed amount written
+		if let Ok(Async::Ready(n)) = res {
+			self.allowed = self.allowed.saturating_sub(n as isize);
+		}
+		res
+	}
+}
+
+/// A Rate Limited Writer
+#[derive(Debug)]
+pub struct ThrottledWriter<W: AsyncWrite> {
+	writer: W,
+	/// Max Bytes per second
+	max: u32,
+	/// Stores a count of last request and last request time
+	allowed: usize,
+	last_check: Instant,
+}
+
+impl<W: AsyncWrite> ThrottledWriter<W> {
+	/// Adds throttling to a writer.
+	/// The resulting writer will write at most `max` amount of bytes per second
+	pub fn new(writer: W, max: u32) -> Self {
+		ThrottledWriter {
+			writer: writer,
+			max: max,
+			allowed: max as usize,
+			last_check: Instant::now(),
+		}
+	}
+
+	/// Get a shared reference to the inner sink.
+	pub fn get_ref(&self) -> &W {
+		&self.writer
+	}
+
+	/// Get a mutable reference to the inner sink.
+	pub fn get_mut(&mut self) -> &mut W {
+		&mut self.writer
+	}
+
+	/// Consumes this combinator, returning the underlying sink.
+	///
+	/// Note that this may discard intermediate state of this combinator, so
+	/// care should be taken to avoid losing resources when this is called.
+	pub fn into_inner(self) -> W {
+		self.writer
+	}
+}
+
+impl<W: AsyncWrite> io::Write for ThrottledWriter<W> {
+	fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+		self.writer.write(buf)
+	}
+
+	fn flush(&mut self) -> io::Result<()> {
+		self.writer.flush()
+	}
+}
+
+impl<T: AsyncWrite> AsyncWrite for ThrottledWriter<T> {
+	fn shutdown(&mut self) -> Poll<(), io::Error> {
+		self.writer.shutdown()
+	}
+
+	fn write_buf<B: Buf>(&mut self, buf: &mut B) -> Poll<usize, io::Error>
+		where Self: Sized
+	{
+		// Check passed Time
+		let time_passed = self.last_check.elapsed();
+		self.last_check = Instant::now();
+		self.allowed += time_passed.as_secs() as usize * self.max as usize;
+
+		// Throttle
+		if self.allowed > self.max as usize {
+			self.allowed = self.max as usize;
+		}
+
+		// Check if Allowed
+		if self.allowed < 1 {
+			return Ok(Async::NotReady);
+		}
+
+		// Write max allowed
+		let ref mut lbuf = buf.by_ref().take(self.allowed);
+		let res = self.writer.write_buf(lbuf);
+
+		// Decrement Allowed amount written
+		if let Ok(Async::Ready(n)) = res {
+			self.allowed -= n;
+		}
+		res
+	}
+}

p2p/src/server.rs

@@ -132,11 +132,9 @@ impl Server {
 			let mut stop_mut = self.stop.borrow_mut();
 			*stop_mut = Some(stop);
 		}
-		Box::new(server.select(stop_rx.map_err(|_| Error::ConnectionClose)).then(|res| {
-			match res {
-				Ok((_, _)) => Ok(()),
-				Err((e, _)) => Err(e),
-			}
+		Box::new(server.select(stop_rx.map_err(|_| Error::ConnectionClose)).then(|res| match res {
+			Ok((_, _)) => Ok(()),
+			Err((e, _)) => Err(e),
 		}))
 	}
 
@@ -304,12 +302,10 @@ fn with_timeout<T: 'static>(fut: Box<Future<Item = Result<T, ()>, Error = Error>
                             -> Box<Future<Item = T, Error = Error>> {
 	let timeout = reactor::Timeout::new(Duration::new(5, 0), h).unwrap();
 	let timed = fut.select(timeout.map(Err).from_err())
-		.then(|res| {
-			match res {
-				Ok((Ok(inner), _timeout)) => Ok(inner),
-				Ok((_, _accept)) => Err(Error::Timeout),
-				Err((e, _other)) => Err(e),
-			}
+		.then(|res| match res {
+			Ok((Ok(inner), _timeout)) => Ok(inner),
+			Ok((_, _accept)) => Err(Error::Timeout),
+			Err((e, _other)) => Err(e),
 		});
 	Box::new(timed)
 }

p2p/tests/peer_handshake.rs

@@ -30,49 +30,59 @@ use core::ser;
 use core::core::target::Difficulty;
 use p2p::Peer;
 
-// Starts a server and connects a client peer to it to check handshake, followed by a ping/pong exchange to make sure the connection is live.
+// Starts a server and connects a client peer to it to check handshake,
+// followed by a ping/pong exchange to make sure the connection is live.
 #[test]
 fn peer_handshake() {
-  env_logger::init().unwrap();
+	env_logger::init().unwrap();
 
-  let mut evtlp = Core::new().unwrap();
-  let handle = evtlp.handle();
-  let p2p_conf = p2p::P2PConfig::default();
-  let net_adapter = Arc::new(p2p::DummyAdapter{});
-  let server = p2p::Server::new(p2p::UNKNOWN, p2p_conf, net_adapter.clone());
-  let run_server = server.start(handle.clone());
-  let my_addr = "127.0.0.1:5000".parse().unwrap();
+	let mut evtlp = Core::new().unwrap();
+	let handle = evtlp.handle();
+	let p2p_conf = p2p::P2PConfig::default();
+	let net_adapter = Arc::new(p2p::DummyAdapter {});
+	let server = p2p::Server::new(p2p::UNKNOWN, p2p_conf, net_adapter.clone());
+	let run_server = server.start(handle.clone());
+	let my_addr = "127.0.0.1:5000".parse().unwrap();
 
-  let phandle = handle.clone();
-  let rhandle = handle.clone();
-  let timeout = reactor::Timeout::new(time::Duration::new(1, 0), &handle).unwrap();
-  let timeout_send = reactor::Timeout::new(time::Duration::new(2, 0), &handle).unwrap();
-  handle.spawn(timeout.from_err().and_then(move |_| {
-    let p2p_conf = p2p::P2PConfig::default();
-    let addr = SocketAddr::new(p2p_conf.host, p2p_conf.port);
-    let socket = TcpStream::connect(&addr, &phandle).map_err(|e| p2p::Error::Connection(e));
-    socket.and_then(move |socket| {
-      Peer::connect(socket, p2p::UNKNOWN, Difficulty::one(), my_addr, &p2p::handshake::Handshake::new())
-		}).and_then(move |(socket, peer)| {
-      rhandle.spawn(peer.run(socket, net_adapter.clone()).map_err(|e| {
-        panic!("Client run failed: {:?}", e);
-      }));
-      peer.send_ping().unwrap();
-      timeout_send.from_err().map(|_| peer)
-		}).and_then(|peer| {
-      let (sent, recv) = peer.transmitted_bytes();
-      assert!(sent > 0);
-      assert!(recv > 0);
-      Ok(())
-    }).and_then(|_| {
-      assert!(server.peer_count() > 0);
-      server.stop();
-      Ok(())
-    })
-  }).map_err(|e| {
-    panic!("Client connection failed: {:?}", e);
-  }));
+	let phandle = handle.clone();
+	let rhandle = handle.clone();
+	let timeout = reactor::Timeout::new(time::Duration::new(1, 0), &handle).unwrap();
+	let timeout_send = reactor::Timeout::new(time::Duration::new(2, 0), &handle).unwrap();
+	handle.spawn(timeout.from_err()
+		.and_then(move |_| {
+			let p2p_conf = p2p::P2PConfig::default();
+			let addr = SocketAddr::new(p2p_conf.host, p2p_conf.port);
+			let socket = TcpStream::connect(&addr, &phandle).map_err(|e| p2p::Error::Connection(e));
+			socket.and_then(move |socket| {
+					Peer::connect(socket,
+					              p2p::UNKNOWN,
+					              Difficulty::one(),
+					              my_addr,
+					              &p2p::handshake::Handshake::new())
+				})
+				.and_then(move |(socket, peer)| {
+					rhandle.spawn(peer.run(socket, net_adapter.clone()).map_err(|e| {
+						panic!("Client run failed: {:?}", e);
+					}));
+					peer.send_ping().unwrap();
+					timeout_send.from_err().map(|_| peer)
+				})
+				.and_then(|peer| {
+					let (sent, recv) = peer.transmitted_bytes();
+					assert!(sent > 0);
+					assert!(recv > 0);
+					Ok(())
+				})
+				.and_then(|_| {
+					assert!(server.peer_count() > 0);
+					server.stop();
+					Ok(())
+				})
+		})
+		.map_err(|e| {
+			panic!("Client connection failed: {:?}", e);
+		}));
 
-  evtlp.run(run_server).unwrap();
+	evtlp.run(run_server).unwrap();
 
 }