feat(quic): allow setting the MTU discovery upper bound

The default MTU discovery upper bound is too high for some environments and results in permanent warnings. As I'd like to be able to configure this setting, adding a new method for the `Config`.

Pull-Request: #5386.

Cargo.toml

@@ -95,7 +95,7 @@ libp2p-perf = { version = "0.3.0", path = "protocols/perf" }
 libp2p-ping = { version = "0.44.1", path = "protocols/ping" }
 libp2p-plaintext = { version = "0.41.0", path = "transports/plaintext" }
 libp2p-pnet = { version = "0.24.0", path = "transports/pnet" }
-libp2p-quic = { version = "0.10.2", path = "transports/quic" }
+libp2p-quic = { version = "0.10.3", path = "transports/quic" }
 libp2p-relay = { version = "0.17.2", path = "protocols/relay" }
 libp2p-rendezvous = { version = "0.14.0", path = "protocols/rendezvous" }
 libp2p-request-response = { version = "0.26.2", path = "protocols/request-response" }

transports/quic/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.10.3
+- Allow configuring MTU discovery upper bound.
+  See [PR 5386](https://github.com/libp2p/rust-libp2p/pull/5386).
+
 ## 0.10.2
 
 - Change `max_idle_timeout`to 10s.

transports/quic/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "libp2p-quic"
-version = "0.10.2"
+version = "0.10.3"
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2021"
 rust-version = { workspace = true }

transports/quic/src/config.rs

@@ -40,10 +40,10 @@ pub struct Config {
     /// concurrently by the remote peer.
     pub max_concurrent_stream_limit: u32,
 
-    /// Max unacknowledged data in bytes that may be send on a single stream.
+    /// Max unacknowledged data in bytes that may be sent on a single stream.
     pub max_stream_data: u32,
 
-    /// Max unacknowledged data in bytes that may be send in total on all streams
+    /// Max unacknowledged data in bytes that may be sent in total on all streams
     /// of a connection.
     pub max_connection_data: u32,
 
@@ -90,6 +90,14 @@ impl Config {
         }
     }
 
+    /// Set the upper bound to the max UDP payload size that MTU discovery will search for.
+    pub fn mtu_upper_bound(mut self, value: u16) -> Self {
+        self.mtu_discovery_config
+            .get_or_insert_with(Default::default)
+            .upper_bound(value);
+        self
+    }
+
     /// Disable MTU path discovery (it is enabled by default).
     pub fn disable_path_mtu_discovery(mut self) -> Self {
         self.mtu_discovery_config = None;