With this patch, implementations of `ConnectionHandler` (which are typically composed in a tree) can exchange information about the supported protocols of a remote with each other via `ConnectionHandlerEvent::ReportRemoteProtocols`. The provided `ProtocolSupport` enum can describe either additions or removals of the remote peer's protocols.
This information is aggregated in the connection and passed down to the `ConnectionHandler` via `ConnectionEvent::RemoteProtocolsChange`.
Similarly, if the listen protocols of a connection change, all `ConnectionHandler`s on the connection will be notified via `ConnectionEvent::LocalProtocolsChange`. This will allow us to eventually remove `PollParameters` from `NetworkBehaviour`.
This pattern allows protocols on a connection to communicate with each other. For example, protocols like identify can share the list of (supposedly) supported protocols by the remote with all other handlers. A protocol like kademlia can accurately add and remove a remote from its routing table as a result.
Resolves: #2680.
Related: #3124.
Pull-Request: #3651.
The currently provided `ConnectionHandlerUpgrErr` is very hard to use. Not only does it have a long name, it also features 3 levels of nesting which results in a lot of boilerplate. Last but not least, it exposes `multistream-select` as a dependency to all protocols.
We fix all of the above by renaming the type to `StreamUpgradeError` and flattening out its interface. Unrecoverable errors during protocol selection are hidden within the `Io` variant.
Related: #3759.
Pull-Request: #3882.
When an inbound stream upgrade fails, there isn't a whole lot we can do about that in the handler. In fact, for several errors, we wouldn't even know which specific handler to target, for example, `NegotiationFailed`. Similiarly, in case of an IO error during the upgrade, we don't know which handler the stream was eventually meant to be for.
Pull-Request: #3605.
Previously, a protocol could be any sequence of bytes as long as it started with `/`. Now, we directly parse a protocol as `String` which enforces it to be valid UTF8.
To notify users of this change, we delete the `ProtocolName` trait. The new requirement is that users need to provide a type that implements `AsRef<str>`.
We also add a `StreamProtocol` newtype in `libp2p-swarm` which provides an easy way for users to ensure their protocol strings are compliant. The newtype enforces that protocol strings start with `/`. `StreamProtocol` also implements `AsRef<str>`, meaning users can directly use it in their upgrades.
`multistream-select` by itself only changes marginally with this patch. The only thing we enforce in the type-system is that protocols must implement `AsRef<str>`.
Resolves: #2831.
Pull-Request: #3746.
Relayed connections to other peers are created from streams to the relay itself. Internally, such a connection has different states. These however are not relevant to the user and should be encapsulated to allow for more backwards-compatible changes. The only interface exposed is `AsyncRead` and `AsyncWrite`.
Resolves: #3255.
Pull-Request: #3829.
The `unreachable_pub` lint makes us aware of uses of `pub` that are not actually reachable from the crate root. This is considered good because it means reading a `pub` somewhere means it is actually public API. Some of our crates are quite large and keeping their entire API surface in your head is difficult.
We should strive for most items being `pub(crate)`. This lint helps us enforce that.
Pull-Request: #3735.
Previously, the relay server would erroneously send its own `PeerId` in the STOP message to the client upon an incoming relay connection. This is obviously wrong and results in failed connection upgrades in other implementations.
Pull-Request: #3767.
As a relay, when forwarding data between relay-connection-source and -destination and vice versa, flush write side when read currently has no more data available.
Pull-Request: #3765.
Instead of relying on `protoc` and buildscripts, we generate the bindings using `pb-rs` and version them within our codebase. This makes for a better IDE integration, a faster build and an easier use of `rust-libp2p` because we don't force the `protoc` dependency onto them.
Resolves#3024.
Pull-Request: #3312.
Previously, a `ConnectionHandler` was immediately requested from the `NetworkBehaviour` as soon as a new dial was initiated or a new incoming connection accepted.
With this patch, we delay the creation of the handler until the connection is actually established and fully upgraded, i.e authenticated and multiplexed.
As a consequence, `NetworkBehaviour::new_handler` is now deprecated in favor of a new set of callbacks:
- `NetworkBehaviour::handle_pending_inbound_connection`
- `NetworkBehaviour::handle_pending_outbound_connection`
- `NetworkBehaviour::handle_established_inbound_connection`
- `NetworkBehaviour::handle_established_outbound_connection`
All callbacks are fallible, allowing the `NetworkBehaviour` to abort the connection either immediately or after it is fully established. All callbacks also receive a `ConnectionId` parameter which uniquely identifies the connection. For example, in case a `NetworkBehaviour` issues a dial via `NetworkBehaviourAction::Dial`, it can unambiguously detect this dial in these lifecycle callbacks via the `ConnectionId`.
Finally, `NetworkBehaviour::handle_pending_outbound_connection` also replaces `NetworkBehaviour::addresses_of_peer` by allowing the behaviour to return more addresses to be used for the dial.
Resolves#2824.
Pull-Request: #3254.
We create the `ConnectionId` for the new connection as part of `DialOpts`. This allows `NetworkBehaviour`s to accurately track state regarding their own dial attempts.
This patch is the main enabler of https://github.com/libp2p/rust-libp2p/pull/3254. Removing the `handler` field will allow us to deprecate the `NetworkBehaviour::new_handler` function in favor of four new ones that give more control over the connection lifecycle.
Previously, we used the full reference to the `OutEvent` of the `ConnectionHandler` in all implementations of `NetworkBehaviour`. Not only is this very verbose, it is also more brittle to changes. With the current implementation plan for #2824, we will be removing the `IntoConnectionHandler` abstraction. Using a type-alias to refer to the `OutEvent` makes the migration much easier.
Storing `NetworkBehaviourAction`s within the behaviour is more flexible than only storing `OutEvent`s. Additionally, I find expression-oriented code easier to reason about because it typically doesn't contain side-effects.
This patch deprecates 3 out of 4 functions on `PollParameters`:
- `local_peer_id`
- `listened_addresses`
- `external_addresses`
The addresses can be obtained by inspecting the `FromSwarm` event. To make this easier, we introduce two utility structs in `libp2p-swarm`:
- `ExternalAddresses`
- `ListenAddresses`
A node's `PeerId` is always known to the caller, thus we can require them to pass it in.
Related: #3124.
Previously, we had one callback for each kind of message that a `ConnectionHandler` would receive from either its `NetworkBehaviour` or the connection itself.
With this patch, we combine these functions, resulting in two callbacks:
- `on_behaviour_event`
- `on_connection_event`
Resolves#3080.
Previously, the `DummyConnectionHandler` offered a "keep alive" functionality,
i.e. it allowed users to set the value of what is returned from
`ConnectionHandler::keep_alive`. This handler is primarily used in tests or
`NetworkBehaviour`s that don't open any connections (like mDNS). In all of these
cases, it is statically known whether we want to keep connections alive. As
such, this functionality is better represented by a static
`KeepAliveConnectionHandler` that always returns `KeepAlive::Yes` and a
`DummyConnectionHandler` that always returns `KeepAlive::No`.
To follow the naming conventions described in
https://github.com/libp2p/rust-libp2p/issues/2217, we introduce a top-level
`keep_alive` and `dummy` behaviour in `libp2p-swarm` that contains both the
`NetworkBehaviour` and `ConnectionHandler` implementation for either case.
* misc/metrics: Explicitly delegate event recording to each recorder
This allows delegating a single event to multiple `Recorder`s. That enables e.g. the
`identify::Metrics` `Recorder` to act both on `IdentifyEvent` and `SwarmEvent`. The latter enables
it to garbage collect per peer data on disconnects.
* protocols/dcutr: Expose PROTOCOL_NAME
* protocols/identify: Expose PROTOCOL_NAME and PUSH_PROTOCOL_NAME
* protocols/ping: Expose PROTOCOL_NAME
* protocols/relay: Expose HOP_PROTOCOL_NAME and STOP_PROTOCOL_NAME
* misc/metrics: Track # connected nodes supporting specific protocol
An example metric exposed with this patch:
```
libp2p_identify_protocols{protocol="/ipfs/ping/1.0.0"} 10
```
This implies that 10 of the currently connected nodes support the ping protocol.
Remove the concept of individual `Transport::Listener` streams from `Transport`.
Instead the `Transport` is polled directly via `Transport::poll`. The
`Transport` is now responsible for driving its listeners.
* protocols/relay: Use prost-codec
* protocols/relay: Respond to at most one incoming reservation request
Also changes poll order prioritizing
- Error handling over everything.
- Queued events over existing circuits.
- Existing circuits over accepting new circuits.
- Reservation management of existing reservation over new reservation
requests.
* protocols/relay: Deny <= 8 incoming circuit requests with one per peer
* protocols/relay: Deny new circuits before accepting new circuits
Previously `libp2p-swarm` required a `Transport` to be `Clone`. Methods
on `Transport`, e.g. `Transport::dial` would take ownership, requiring
e.g. a `Clone::clone` before calling `Transport::dial`.
The requirement of `Transport` to be `Clone` is no longer needed in
`libp2p-swarm`. E.g. concurrent dialing can be done without a clone per
dial.
This commit removes the requirement of `Clone` for `Transport` in
`libp2p-swarm`. As a follow-up methods on `Transport` no longer take
ownership, but instead a mutable reference (`&mut self`).
On the one hand this simplifies `libp2p-swarm`, on the other it
simplifies implementations of `Transport`.
A `ProtocolsHandler`, now `ConnectionHandler`, handels a connection, not
a protocol. Thus the name `CONNECTIONHandler` is more appropriate.
Next to the rename of `ProtocolsHandler` this commit renames the `mod
protocols_handler` to `mod handler`. Finally all combinators (e.g.
`ProtocolsHandlerSelect`) are renamed appropriately.
When a peer disconnects, reservations associated with that peer are removed from
the set of reservations of the peer. In case the set of reservations for the
peer is now empty, remove the entire peer.
Same when a reservation times out.
Allows `NetworkBehaviour` implementations to dial a peer, but instruct
the dialed connection to be upgraded as if it were the listening
endpoint.
This is needed when establishing direct connections through NATs and/or
Firewalls (hole punching). When hole punching via TCP (QUIC is different
but similar) both ends dial the other at the same time resulting in a
simultaneously opened TCP connection. To disambiguate who is the dialer
and who the listener there are two options:
1. Use the Simultaneous Open Extension of Multistream Select. See
[sim-open] specification and [sim-open-rust] Rust implementation.
2. Disambiguate the role (dialer or listener) based on the role within
the DCUtR [dcutr] protocol. More specifically the node initiating the
DCUtR process will act as a listener and the other as a dialer.
This commit enables (2), i.e. enables the DCUtR protocol to specify the
role used once the connection is established.
While on the positive side (2) requires one round trip less than (1), on
the negative side (2) only works for coordinated simultaneous dials.
I.e. when a simultaneous dial happens by chance, and not coordinated via
DCUtR, the connection attempt fails when only (2) is in place.
[sim-open]: https://github.com/libp2p/specs/blob/master/connections/simopen.md
[sim-open-rust]: https://github.com/libp2p/rust-libp2p/pull/2066
[dcutr]: https://github.com/libp2p/specs/blob/master/relay/DCUtR.md
This commit adds an implementation for the circuit relay v2 protocol to be used
as a relay server, i.e. it supports incoming HOP requests and outgoing STOP
requests and used as a relay clients, i.e. outgoing HOP requests and incoming
STOP requests.
The existing circuit relay v1 protocol implementation is moved to
protocols/relay/src/v1.
Co-authored-by: ronzigelman <ronzigelman@gmail.com>
Co-authored-by: Marco Munizaga <git@marcopolo.io>
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
Co-authored-by: Elena Frank <57632201+elenaf9@users.noreply.github.com>
Enable advanced dialing requests both on `Swarm` and via
`NetworkBehaviourAction`. Users can now trigger a dial with a specific
set of addresses, optionally extended via
`NetworkBehaviour::addresses_of_peer`. In addition the whole process is
now modelled in a type safe way via the builder pattern.
Example of a `NetworkBehaviour` requesting a dial to a specific peer
with a set of addresses additionally extended through
`NetworkBehaviour::addresses_of_peer`:
```rust
NetworkBehaviourAction::Dial {
opts: DialOpts::peer_id(peer_id)
.condition(PeerCondition::Always)
.addresses(addresses)
.extend_addresses_through_behaviour()
.build(),
handler,
}
```
Example of a user requesting a dial to an unknown peer with a single
address via `Swarm`:
```rust
swarm1.dial(
DialOpts::unknown_peer_id()
.address(addr2.clone())
.build()
)
```
Changes needed to get libp2p to run via `wasm32-unknown-unknown` in the browser
(both main thread and inside web workers).
Replaces wasm-timer with futures-timer and instant.
Co-authored-by: Oliver Wangler <oliver@wngr.de>
