protocols: Implement Direct Connection Upgrade through Relay (dcutr)

Cargo.toml

@@ -33,6 +33,7 @@ default = [
     "websocket",
     "yamux",
 ]
+dcutr = ["libp2p-dcutr"]
 deflate = ["libp2p-deflate"]
 dns-async-std = ["libp2p-dns", "libp2p-dns/async-std"]
 dns-tokio = ["libp2p-dns", "libp2p-dns/tokio"]
@@ -47,7 +48,7 @@ noise = ["libp2p-noise"]
 ping = ["libp2p-ping", "libp2p-metrics/ping"]
 plaintext = ["libp2p-plaintext"]
 pnet = ["libp2p-pnet"]
-relay = ["libp2p-relay"]
+relay = ["libp2p-relay", "libp2p-metrics/relay"]
 request-response = ["libp2p-request-response"]
 rendezvous = ["libp2p-rendezvous"]
 tcp-async-io = ["libp2p-tcp", "libp2p-tcp/async-io"]
@@ -72,6 +73,7 @@ getrandom = "0.2.3" # Explicit dependency to be used in `wasm-bindgen` feature
 instant = "0.1.11" # Explicit dependency to be used in `wasm-bindgen` feature
 lazy_static = "1.2"
 libp2p-core = { version = "0.30.0", path = "core",  default-features = false }
+libp2p-dcutr = { version = "0.1.0", path = "protocols/dcutr",  optional = true }
 libp2p-floodsub = { version = "0.32.0", path = "protocols/floodsub", optional = true }
 libp2p-gossipsub = { version = "0.35.0", path = "./protocols/gossipsub", optional = true }
 libp2p-identify = { version = "0.32.0", path = "protocols/identify", optional = true }
@@ -119,6 +121,7 @@ members = [
     "misc/peer-id-generator",
     "muxers/mplex",
     "muxers/yamux",
+    "protocols/dcutr",
     "protocols/floodsub",
     "protocols/gossipsub",
     "protocols/rendezvous",

core/CHANGELOG.md

@@ -80,7 +80,43 @@
   Introduce `upgrade::read_length_prefixed` and `upgrade::write_length_prefixed`.
   See [PR 2111](https://github.com/libp2p/rust-libp2p/pull/2111).
 
+- Add support for multistream-select [simultaneous open extension] to assign _initiator_ and
+  _responder_ role during authentication protocol negotiation on simultaneously opened connection.
+
+  This is one important component of the greater effort to support hole punching in rust-libp2p.
+
+  - `Transport::upgrade` no longer takes a multistream-select `Version`. Instead the
+     multistream-select `Version`s `V1`, `V1Lazy` and `V1SimultaneousOpen` can be selected when
+     setting the authentication upgrade via `Builder::authenticate_with_version` and the
+     multistream-select `Version`s `V1` and `V1Lazy` can be selected when setting the multiplexing
+     upgrade via `Builder::multiplex_with_version`.
+
+     Users merely wanting to maintain the status quo should use the following call chain depending
+     on which `Version` they previously used:
+
+     - `Version::V1`
+
+       ```rust
+       my_transport.upgrade()
+         .authenticate(my_authentication)
+         .multiplex(my_multiplexer)
+       ```
+     - `Version::V1Lazy`
+
+       ```rust
+       my_transport.upgrade()
+         .authenticate_with_version(my_authentication, Version::V1Lazy)
+         .multiplex_with_version(my_multiplexer, Version::V1Lazy)
+       ```
+
+  - `Builder::multiplex_ext` is removed in favor of the new simultaneous open workflow. Please reach
+    out in case you depend on `Builder::multiplex_ext`.
+
+  See [PR 2066].
+
 [PR 2090]: https://github.com/libp2p/rust-libp2p/pull/2090
+[simultaneous open extension]: https://github.com/libp2p/specs/blob/master/connections/simopen.md
+[PR 2066]: https://github.com/libp2p/rust-libp2p/pull/2066
 
 # 0.28.3 [2021-04-26]
 

core/Cargo.toml

@@ -23,7 +23,7 @@ libsecp256k1 = { version = "0.7.0", optional = true }
 log = "0.4"
 multiaddr = { version = "0.13.0" }
 multihash = { version = "0.14", default-features = false, features = ["std", "multihash-impl", "identity", "sha2"] }
-multistream-select = { version = "0.10", path = "../misc/multistream-select" }
+multistream-select = { version = "0.11", path = "../misc/multistream-select" }
 parking_lot = "0.11.0"
 pin-project = "1.0.0"
 prost = "0.9"

core/src/connection/listeners.rs

@@ -412,8 +412,6 @@ where
 
 #[cfg(test)]
 mod tests {
-    use futures::{future::BoxFuture, stream::BoxStream};
-
     use super::*;
     use crate::transport;
 
@@ -463,12 +461,18 @@ mod tests {
         impl transport::Transport for DummyTrans {
             type Output = ();
             type Error = std::io::Error;
-            type Listener = BoxStream<
-                'static,
-                Result<ListenerEvent<Self::ListenerUpgrade, std::io::Error>, std::io::Error>,
+            type Listener = Pin<
+                Box<
+                    dyn Stream<
+                        Item = Result<
+                            ListenerEvent<Self::ListenerUpgrade, std::io::Error>,
+                            std::io::Error,
+                        >,
+                    >,
+                >,
             >;
-            type ListenerUpgrade = BoxFuture<'static, Result<Self::Output, Self::Error>>;
-            type Dial = BoxFuture<'static, Result<Self::Output, Self::Error>>;
+            type ListenerUpgrade = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>>>>;
+            type Dial = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>>>>;
 
             fn listen_on(
                 self,
@@ -519,12 +523,18 @@ mod tests {
         impl transport::Transport for DummyTrans {
             type Output = ();
             type Error = std::io::Error;
-            type Listener = BoxStream<
-                'static,
-                Result<ListenerEvent<Self::ListenerUpgrade, std::io::Error>, std::io::Error>,
+            type Listener = Pin<
+                Box<
+                    dyn Stream<
+                        Item = Result<
+                            ListenerEvent<Self::ListenerUpgrade, std::io::Error>,
+                            std::io::Error,
+                        >,
+                    >,
+                >,
             >;
-            type ListenerUpgrade = BoxFuture<'static, Result<Self::Output, Self::Error>>;
-            type Dial = BoxFuture<'static, Result<Self::Output, Self::Error>>;
+            type ListenerUpgrade = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>>>>;
+            type Dial = Pin<Box<dyn Future<Output = Result<Self::Output, Self::Error>>>>;
 
             fn listen_on(
                 self,

core/src/transport.rs

@@ -46,7 +46,6 @@ pub use self::boxed::Boxed;
 pub use self::choice::OrTransport;
 pub use self::memory::MemoryTransport;
 pub use self::optional::OptionalTransport;
-pub use self::upgrade::Upgrade;
 
 /// A transport provides connection-oriented communication between two peers
 /// through ordered streams of data (i.e. connections).
@@ -198,12 +197,12 @@ pub trait Transport {
 
     /// Begins a series of protocol upgrades via an
     /// [`upgrade::Builder`](upgrade::Builder).
-    fn upgrade(self, version: upgrade::Version) -> upgrade::Builder<Self>
+    fn upgrade(self) -> upgrade::Builder<Self>
     where
         Self: Sized,
         Self::Error: 'static,
     {
-        upgrade::Builder::new(self, version)
+        upgrade::Builder::new(self)
     }
 }