Re-implemented the whole interaction between server, peer and protocol to be more Rust-ish. Server maintains peer references and protocol is internally mutable.

core/src/core/block.rs

@@ -218,7 +218,7 @@ impl Block {
 		// repeated iterations, revisit if a problem
 
 		// validate each transaction and gather their proofs
-		let mut proofs = try_oap_vec!(txs, |tx| tx.verify_sig(&secp));
+		let mut proofs = try_map_vec!(txs, |tx| tx.verify_sig(&secp));
 		proofs.push(reward_proof);
 
 		// build vectors with all inputs and all outputs, ordering them by hash

core/src/macros.rs

@@ -29,7 +29,7 @@ macro_rules! map_vec {
 /// Same as map_vec when the map closure returns Results. Makes sure the
 /// results are "pushed up" and wraps with a try.
 #[macro_export]
-macro_rules! try_oap_vec {
+macro_rules! try_map_vec {
   ($thing:expr, $mapfn:expr ) => {
     try!($thing.iter()
       .map($mapfn)

p2p/src/handshake.rs

@@ -17,12 +17,12 @@ use std::sync::RwLock;
 
 use rand::Rng;
 use rand::os::OsRng;
+use mioco::tcp::{TcpStream, Shutdown};
 
 use core::ser::{serialize, deserialize, Error};
 use msg::*;
 use types::*;
 use protocol::ProtocolV1;
-use peer::PeerConn;
 
 const NONCES_CAP: usize = 100;
 
@@ -44,20 +44,20 @@ impl Handshake {
 	}
 
 	/// Handles connecting to a new remote peer, starting the version handshake.
-	pub fn connect<'a>(&'a self, peer: &'a mut PeerConn) -> Result<Box<Protocol + 'a>, Error> {
+	pub fn connect(&self, mut conn: TcpStream) -> Result<(Box<Protocol>, PeerInfo), Error> {
 		// get a new nonce that can be used on handshake to detect self-connection
 		let nonce = self.next_nonce();
 
 		// send the first part of the handshake
-		let sender_addr = SockAddr(peer.local_addr());
-		let receiver_addr = SockAddr(peer.peer_addr());
-		let opt_err = serialize(peer,
+		let sender_addr = conn.local_addr().unwrap();
+		let receiver_addr = conn.peer_addr().unwrap();
+		let opt_err = serialize(&mut conn,
 		                        &Hand {
 			                        version: PROTOCOL_VERSION,
 			                        capabilities: FULL_SYNC,
 			                        nonce: nonce,
-			                        sender_addr: sender_addr,
-			                        receiver_addr: receiver_addr,
+			                        sender_addr: SockAddr(sender_addr),
+			                        receiver_addr: SockAddr(receiver_addr),
 			                        user_agent: USER_AGENT.to_string(),
 		                        });
 		match opt_err {
@@ -66,9 +66,9 @@ impl Handshake {
 		}
 
 		// deserialize the handshake response and do version negotiation
-		let shake = try!(deserialize::<Shake>(peer));
+		let shake = try!(deserialize::<Shake>(&mut conn));
 		if shake.version != 1 {
-			self.close(peer,
+			self.close(&mut conn,
 			           ErrCodes::UnsupportedVersion as u32,
 			           format!("Unsupported version: {}, ours: {})",
 			                   shake.version,
@@ -78,61 +78,70 @@ impl Handshake {
 				received: vec![shake.version as u8],
 			});
 		}
-		peer.capabilities = shake.capabilities;
-		peer.user_agent = shake.user_agent;
 
-		info!("Connected to peer {}", peer);
+    let peer_info = PeerInfo{
+		  capabilities: shake.capabilities,
+		  user_agent: shake.user_agent,
+      addr: receiver_addr,
+      version: shake.version,
+    };
+
+		info!("Connected to peer {:?}", peer_info);
 		// when more than one protocol version is supported, choosing should go here
-		Ok(Box::new(ProtocolV1::new(peer)))
+		Ok((Box::new(ProtocolV1::new(conn)), peer_info))
 	}
 
 	/// Handles receiving a connection from a new remote peer that started the
 	/// version handshake.
-	pub fn handshake<'a>(&'a self, peer: &'a mut PeerConn) -> Result<Box<Protocol + 'a>, Error> {
-		// deserialize first part of handshake sent to us and do version negotiation
-		let hand = try!(deserialize::<Hand>(peer));
-		if hand.version != 1 {
-			self.close(peer,
-			           ErrCodes::UnsupportedVersion as u32,
-			           format!("Unsupported version: {}, ours: {})",
-			                   hand.version,
-			                   PROTOCOL_VERSION));
-			return Err(Error::UnexpectedData {
-				expected: vec![PROTOCOL_VERSION as u8],
-				received: vec![hand.version as u8],
-			});
-		}
-		{
-			// check the nonce to see if we could be trying to connect to ourselves
-			let nonces = self.nonces.read().unwrap();
-			if nonces.contains(&hand.nonce) {
-				return Err(Error::UnexpectedData {
-					expected: vec![],
-					received: vec![],
-				});
-			}
-		}
+	pub fn handshake(&self, mut conn: TcpStream) -> Result<(Box<Protocol>, PeerInfo), Error> {
+ 		// deserialize first part of handshake sent to us and do version negotiation
+ 		let hand = try!(deserialize::<Hand>(&mut conn));
+ 		if hand.version != 1 {
+ 			self.close(&mut conn,
+ 			           ErrCodes::UnsupportedVersion as u32,
+ 			           format!("Unsupported version: {}, ours: {})",
+ 			                   hand.version,
+ 			                   PROTOCOL_VERSION));
+ 			return Err(Error::UnexpectedData {
+ 				expected: vec![PROTOCOL_VERSION as u8],
+ 				received: vec![hand.version as u8],
+ 			});
+ 		}
+ 		{
+ 			// check the nonce to see if we could be trying to connect to ourselves
+ 			let nonces = self.nonces.read().unwrap();
+ 			if nonces.contains(&hand.nonce) {
+ 				return Err(Error::UnexpectedData {
+ 					expected: vec![],
+ 					received: vec![],
+ 				});
+ 			}
+ 		}
+ 
+ 		// all good, keep peer info
+    let peer_info = PeerInfo{
+		  capabilities: hand.capabilities,
+		  user_agent: hand.user_agent,
+      addr: conn.peer_addr().unwrap(),
+      version: hand.version,
+    };
 
-		// all good, keep peer info
-		peer.capabilities = hand.capabilities;
-		peer.user_agent = hand.user_agent;
-
-		// send our reply with our info
-		let opt_err = serialize(peer,
-		                        &Shake {
-			                        version: PROTOCOL_VERSION,
-			                        capabilities: FULL_SYNC,
-			                        user_agent: USER_AGENT.to_string(),
-		                        });
-		match opt_err {
-			Some(err) => return Err(err),
-			None => {}
-		}
-
-		info!("Received connection from peer {}", peer);
-		// when more than one protocol version is supported, choosing should go here
-		Ok(Box::new(ProtocolV1::new(peer)))
-	}
+ 		// send our reply with our info
+ 		let opt_err = serialize(&mut conn,
+ 		                        &Shake {
+ 			                        version: PROTOCOL_VERSION,
+ 			                        capabilities: FULL_SYNC,
+ 			                        user_agent: USER_AGENT.to_string(),
+ 		                        });
+ 		match opt_err {
+ 			Some(err) => return Err(err),
+ 			None => {}
+ 		}
+ 
+ 		info!("Received connection from peer {:?}", peer_info);
+ 		// when more than one protocol version is supported, choosing should go here
+		Ok((Box::new(ProtocolV1::new(conn)), peer_info))
+ 	}
 
 	/// Generate a new random nonce and store it in our ring buffer
 	fn next_nonce(&self) -> u64 {
@@ -147,12 +156,12 @@ impl Handshake {
 		nonce
 	}
 
-	fn close(&self, peer: &mut PeerConn, err_code: u32, explanation: String) {
-		serialize(peer,
+	fn close(&self, conn: &mut TcpStream, err_code: u32, explanation: String) {
+		serialize(conn,
 		          &PeerError {
 			          code: err_code,
 			          message: explanation,
 		          });
-		peer.close();
+		conn.shutdown(Shutdown::Both);
 	}
 }

p2p/src/lib.rs

@@ -27,6 +27,7 @@ extern crate bitflags;
 extern crate grin_core as core;
 #[macro_use]
 extern crate log;
+#[macro_use]
 extern crate mioco;
 extern crate rand;
 extern crate time;

p2p/src/msg.rs

@@ -18,6 +18,8 @@ use std::net::*;
 
 use core::ser::{self, Writeable, Readable, Writer, Reader, Error};
 
+use types::*;
+
 /// Current latest version of the protocol
 pub const PROTOCOL_VERSION: u32 = 1;
 /// Grin's user agent with current version (TODO externalize)
@@ -31,16 +33,6 @@ pub enum ErrCodes {
 	UnsupportedVersion = 100,
 }
 
-bitflags! {
-  /// Options for block validation
-  pub flags Capabilities: u32 {
-    /// We don't know (yet) what the peer can do.
-    const UNKNOWN = 0b00000000,
-    /// Runs with the easier version of the Proof of Work, mostly to make testing easier.
-    const FULL_SYNC = 0b00000001,
-  }
-}
-
 /// Types of messages
 #[derive(Clone, Copy)]
 pub enum Type {
@@ -49,6 +41,8 @@ pub enum Type {
 	SHAKE,
 	PING,
 	PONG,
+	GETPEERADDRS,
+	PEERADDRS,
 	/// Never used over the network but to detect unrecognized types.
 	MaxMsgType,
 }
@@ -92,6 +86,8 @@ impl Readable<MsgHeader> for MsgHeader {
 				2 => Type::SHAKE,
 				3 => Type::PING,
 				4 => Type::PONG,
+				5 => Type::GETPEERADDRS,
+				6 => Type::PEERADDRS,
 				_ => panic!(),
 			},
 		})
@@ -180,6 +176,54 @@ impl Readable<Shake> for Shake {
 	}
 }
 
+/// Ask for other peers addresses, required for network discovery.
+pub struct GetPeerAddrs {
+	/// Filters on the capabilities we'd like the peers to have
+	pub capabilities: Capabilities,
+}
+
+impl Writeable for GetPeerAddrs {
+	fn write(&self, writer: &mut Writer) -> Option<ser::Error> {
+		writer.write_u32(self.capabilities.bits())
+	}
+}
+
+impl Readable<GetPeerAddrs> for GetPeerAddrs {
+	fn read(reader: &mut Reader) -> Result<GetPeerAddrs, ser::Error> {
+		let capab = try!(reader.read_u32());
+		let capabilities = try!(Capabilities::from_bits(capab).ok_or(ser::Error::CorruptedData));
+		Ok(GetPeerAddrs { capabilities: capabilities })
+	}
+}
+
+/// Peer addresses we know of that are fresh enough, in response to
+/// GetPeerAddrs.
+pub struct PeerAddrs {
+	pub peers: Vec<SockAddr>,
+}
+
+impl Writeable for PeerAddrs {
+	fn write(&self, writer: &mut Writer) -> Option<ser::Error> {
+		try_o!(writer.write_u32(self.peers.len() as u32));
+		for p in &self.peers {
+			p.write(writer);
+		}
+		None
+	}
+}
+
+impl Readable<PeerAddrs> for PeerAddrs {
+	fn read(reader: &mut Reader) -> Result<PeerAddrs, ser::Error> {
+		let peer_count = try!(reader.read_u32());
+		if peer_count > 1000 {
+			return Err(ser::Error::TooLargeReadErr(format!("Too many peers provided: {}",
+			                                               peer_count)));
+		}
+		let peers = try_map_vec!([0..peer_count], |_| SockAddr::read(reader));
+		Ok(PeerAddrs { peers: peers })
+	}
+}
+
 /// We found some issue in the communication, sending an error back, usually
 /// followed by closing the connection.
 pub struct PeerError {
@@ -247,7 +291,7 @@ impl Readable<SockAddr> for SockAddr {
 			                                                           ip[3]),
 			                                             port))))
 		} else {
-			let ip = try_oap_vec!([0..8], |_| reader.read_u16());
+			let ip = try_map_vec!([0..8], |_| reader.read_u16());
 			let port = try!(reader.read_u16());
 			Ok(SockAddr(SocketAddr::V6(SocketAddrV6::new(Ipv6Addr::new(ip[0],
 			                                                           ip[1],

p2p/src/peer.rs

@@ -12,88 +12,40 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::fmt;
-use std::io::{self, Read, Write};
-use std::net::SocketAddr;
+use mioco::tcp::TcpStream;
 
-use mioco::tcp::{TcpStream, Shutdown};
-
-use handshake::Handshake;
 use core::ser::Error;
+use handshake::Handshake;
 use msg::*;
 use types::*;
 
-/// The local representation of a remotely connected peer. Handles most
-/// low-level network communication and tracks peer information.
-pub struct PeerConn {
-	conn: TcpStream,
-	pub capabilities: Capabilities,
-	pub user_agent: String,
+pub struct Peer {
+  info: PeerInfo,
+  proto: Box<Protocol>,
 }
 
-impl fmt::Display for PeerConn {
-	// This trait requires `fmt` with this exact signature.
-	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		write!(f, "{} {}", self.peer_addr(), self.user_agent)
-	}
-}
-
-/// Make the Peer a Reader for convenient access to the underlying connection.
-/// Allows the peer to track how much is received.
-impl Read for PeerConn {
-	fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-		self.conn.read(buf)
-	}
-}
-
-/// Make the Peer a Writer for convenient access to the underlying connection.
-/// Allows the peer to track how much is sent.
-impl Write for PeerConn {
-	fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-		self.conn.write(buf)
-	}
-	fn flush(&mut self) -> io::Result<()> {
-		self.conn.flush()
-	}
-}
-
-impl Close for PeerConn {
-	fn close(&self) {
-		self.conn.shutdown(Shutdown::Both);
-	}
-}
-
-impl PeerConn {
-	/// Create a new local peer instance connected to a remote peer with the
-	/// provided TcpStream.
-	pub fn new(conn: TcpStream) -> PeerConn {
-		// don't wait on read for more than 2 seconds by default
-		conn.set_keepalive(Some(2));
-
-		PeerConn {
-			conn: conn,
-			capabilities: UNKNOWN,
-			user_agent: "".to_string(),
-		}
-	}
-
-	pub fn connect(&mut self, hs: &Handshake, na: &NetAdapter) -> Option<Error> {
-		let mut proto = try_to_o!(hs.connect(self));
-		proto.handle(na)
-	}
-
-	pub fn handshake(&mut self, hs: &Handshake, na: &NetAdapter) -> Option<Error> {
-		let mut proto = try_to_o!(hs.handshake(self));
-		proto.handle(na)
-	}
-}
-
-impl PeerInfo for PeerConn {
-	fn peer_addr(&self) -> SocketAddr {
-		self.conn.peer_addr().unwrap()
-	}
-	fn local_addr(&self) -> SocketAddr {
-		// TODO likely not exactly what we want (private vs public IP)
-		self.conn.local_addr().unwrap()
-	}
+unsafe impl Sync for Peer {}
+unsafe impl Send for Peer {}
+
+impl Peer {
+
+	pub fn connect(conn: TcpStream, hs: &Handshake) -> Result<Peer, Error> {
+		let (proto, info) = try!(hs.connect(conn));
+    Ok(Peer{
+      info: info,
+      proto: proto,
+    })
+  }
+
+	pub fn accept(conn: TcpStream, hs: &Handshake) -> Result<Peer, Error> {
+		let (proto, info) = try!(hs.handshake(conn));
+    Ok(Peer{
+      info: info,
+      proto: proto,
+    })
+  }
+
+  pub fn run(&self, na: &NetAdapter) -> Option<Error> {
+    self.proto.handle(na)
+  }
 }

p2p/src/protocol.rs

@@ -12,37 +12,56 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::cell::RefCell;
+use std::ops::DerefMut;
+use std::rc::Rc;
+
+use mioco;
+use mioco::sync::mpsc::sync_channel;
+use mioco::tcp::{TcpStream, Shutdown};
+
 use core::ser;
+use handshake::Handshake;
 use msg::*;
 use types::*;
-use peer::PeerConn;
 
-pub struct ProtocolV1<'a> {
-	peer: &'a mut PeerConn,
+pub struct ProtocolV1 {
+	conn: RefCell<TcpStream>,
 }
 
-impl<'a> Protocol for ProtocolV1<'a> {
-	fn handle(&mut self, server: &NetAdapter) -> Option<ser::Error> {
+impl Protocol for ProtocolV1 {
+	fn handle(&self, server: &NetAdapter) -> Option<ser::Error> {
+    // setup a channel so we can switch between reads and writes
+    let (send, recv) = sync_channel(10);
+
+    let mut conn = self.conn.borrow_mut();
 		loop {
-			let header = try_to_o!(ser::deserialize::<MsgHeader>(self.peer));
-			if !header.acceptable() {
-				continue;
-			}
+      select!(
+        r:conn => {
+          let header = try_to_o!(ser::deserialize::<MsgHeader>(conn.deref_mut()));
+          if !header.acceptable() {
+            continue;
+          }
+        },
+        r:recv => {
+          ser::serialize(conn.deref_mut(), recv.recv().unwrap());
+        }
+      );
 		}
 	}
 }
 
-impl<'a> ProtocolV1<'a> {
-	pub fn new(p: &mut PeerConn) -> ProtocolV1 {
-		ProtocolV1 { peer: p }
+impl ProtocolV1 {
+	pub fn new(conn: TcpStream) -> ProtocolV1 {
+		ProtocolV1 { conn: RefCell::new(conn) }
 	}
 
-	fn close(&mut self, err_code: u32, explanation: &'static str) {
-		ser::serialize(self.peer,
-		               &PeerError {
-			               code: err_code,
-			               message: explanation.to_string(),
-		               });
-		self.peer.close();
-	}
+	// fn close(&mut self, err_code: u32, explanation: &'static str) {
+	// 	ser::serialize(self.conn,
+	// 	               &PeerError {
+	// 		               code: err_code,
+	// 		               message: explanation.to_string(),
+	// 	               });
+	// 	self.conn.shutdown(Shutdown::Both);
+	// }
 }

p2p/src/server.rs

@@ -15,17 +15,18 @@
 //! Grin server implementation, accepts incoming connections and connects to
 //! other peers in the network.
 
+use std::cell::RefCell;
 use std::io;
 use std::net::SocketAddr;
 use std::str::FromStr;
-use std::sync::Arc;
+use std::sync::{Arc, RwLock};
 
 use mioco;
 use mioco::tcp::{TcpListener, TcpStream};
 
 use core::ser::Error;
 use handshake::Handshake;
-use peer::PeerConn;
+use peer::Peer;
 use types::*;
 
 pub const DEFAULT_LISTEN_ADDR: &'static str = "127.0.0.1:3414";
@@ -38,14 +39,20 @@ fn listen_addr() -> SocketAddr {
 struct DummyAdapter {}
 impl NetAdapter for DummyAdapter {}
 
+/// P2P server implementation, handling bootstrapping to find and connect to
+/// peers, receiving connections from other peers and keep track of all of them.
 pub struct Server {
+  peers: RwLock<Vec<Arc<Peer>>>,
 }
 
+// TODO TLS
 impl Server {
+  pub fn new() -> Server {
+    Server{peers: RwLock::new(Vec::new())}
+  }
 	/// Creates a new p2p server. Opens a TCP port to allow incoming
 	/// connections and starts the bootstrapping process to find peers.
-	pub fn start() -> Result<Server, Error> {
-		// TODO TLS
+	pub fn start(&'static self) -> Result<(), Error> {
 		mioco::spawn(move || -> io::Result<()> {
 			let addr = DEFAULT_LISTEN_ADDR.parse().unwrap();
 			let listener = try!(TcpListener::bind(&addr));
@@ -55,11 +62,16 @@ impl Server {
 
 			loop {
 				let conn = try!(listener.accept());
-				let hs_child = hs.clone();
+				let hs = hs.clone();
 
 				mioco::spawn(move || -> io::Result<()> {
-					let ret = PeerConn::new(conn).handshake(&hs_child, &DummyAdapter {});
-					if let Some(err) = ret {
+          let peer = try!(Peer::connect(conn, &hs).map_err(|_| io::Error::last_os_error()));
+          let wpeer = Arc::new(peer);
+          {
+            let mut peers = self.peers.write().unwrap();
+            peers.push(wpeer.clone());
+          }
+          if let Some(err) = wpeer.run(&DummyAdapter{}) {
 						error!("{:?}", err);
 					}
 					Ok(())
@@ -67,18 +79,13 @@ impl Server {
 			}
 			Ok(())
 		});
-		Ok(Server {})
+		Ok(())
 	}
 
 	/// Simulates an unrelated client connecting to our server. Mostly used for
 	/// tests.
-	pub fn connect_as_client(addr: SocketAddr) -> Option<Error> {
+	pub fn connect_as_client(addr: SocketAddr) -> Result<Peer, Error> {
 		let tcp_client = TcpStream::connect(&addr).unwrap();
-		let mut peer = PeerConn::new(tcp_client);
-    let hs = Handshake::new();
-		if let Err(e) = hs.connect(&mut peer) {
-			return Some(e);
-		}
-		None
+		Peer::accept(tcp_client, &Handshake::new())
 	}
 }

p2p/src/types.rs

@@ -16,17 +16,23 @@ use std::io::{Read, Write};
 use std::net::SocketAddr;
 use core::ser::Error;
 
-/// Trait for pre-emptively and forcefully closing an underlying resource.
-pub trait Close {
-	fn close(&self);
+bitflags! {
+  /// Options for block validation
+  pub flags Capabilities: u32 {
+    /// We don't know (yet) what the peer can do.
+    const UNKNOWN = 0b00000000,
+    /// Runs with the easier version of the Proof of Work, mostly to make testing easier.
+    const FULL_SYNC = 0b00000001,
+  }
 }
 
 /// General information about a connected peer that's useful to other modules.
-pub trait PeerInfo {
-	/// Address of the remote peer
-	fn peer_addr(&self) -> SocketAddr;
-	/// Our address, communicated to other peers
-	fn local_addr(&self) -> SocketAddr;
+#[derive(Debug)]
+pub struct PeerInfo {
+	pub capabilities: Capabilities,
+	pub user_agent: String,
+  pub version: u32,
+  pub addr: SocketAddr,
 }
 
 /// A given communication protocol agreed upon between 2 peers (usually
@@ -34,7 +40,7 @@ pub trait PeerInfo {
 pub trait Protocol {
 	/// Starts handling protocol communication, the peer(s) is expected to be
 	/// known already, usually passed during construction.
-	fn handle(&mut self, na: &NetAdapter) -> Option<Error>;
+	fn handle(&self, na: &NetAdapter) -> Option<Error>;
 }
 
 /// Bridge between the networking layer and the rest of the system. Handles the