fix(iroh-net)!: ALPNs can be bytes, not just strings (#2377)

## Breaking Changes

- `iroh_net::endpoint::Connecting::alpn` returns `Vec<u8>` instead of
`String`

Author: dignifiedquire

iroh-gossip/examples/chat.rs

@@ -206,11 +206,11 @@ async fn handle_connection(
     let alpn = conn.alpn().await?;
     let conn = conn.await?;
     let peer_id = iroh_net::endpoint::get_remote_node_id(&conn)?;
-    match alpn.as_bytes() {
-        GOSSIP_ALPN => gossip
-            .handle_connection(conn)
-            .await
-            .context(format!("connection to {peer_id} with ALPN {alpn} failed"))?,
+    match alpn.as_ref() {
+        GOSSIP_ALPN => gossip.handle_connection(conn).await.context(format!(
+            "connection to {peer_id} with ALPN {} failed",
+            String::from_utf8_lossy(&alpn)
+        ))?,
         _ => println!("> ignoring connection from {peer_id}: unsupported ALPN protocol"),
     }
     Ok(())

iroh-net/examples/listen-unreliable.rs

@@ -67,7 +67,8 @@ async fn main() -> anyhow::Result<()> {
         let conn = conn.await?;
         let node_id = iroh_net::endpoint::get_remote_node_id(&conn)?;
         info!(
-            "new (unreliable) connection from {node_id} with ALPN {alpn} (coming from {})",
+            "new (unreliable) connection from {node_id} with ALPN {} (coming from {})",
+            String::from_utf8_lossy(&alpn),
             conn.remote_address()
         );
         // spawn a task to handle reading and writing off of the connection

iroh-net/examples/listen.rs

@@ -66,7 +66,8 @@ async fn main() -> anyhow::Result<()> {
         let conn = conn.await?;
         let node_id = iroh_net::endpoint::get_remote_node_id(&conn)?;
         info!(
-            "new connection from {node_id} with ALPN {alpn} (coming from {})",
+            "new connection from {node_id} with ALPN {} (coming from {})",
+            String::from_utf8_lossy(&alpn),
             conn.remote_address()
         );
 

iroh-net/src/endpoint.rs

@@ -908,11 +908,11 @@ impl Connecting {
     /// Extracts the ALPN protocol from the peer's handshake data.
     // Note, we could totally provide this method to be on a Connection as well.  But we'd
     // need to wrap Connection too.
-    pub async fn alpn(&mut self) -> Result<String> {
+    pub async fn alpn(&mut self) -> Result<Vec<u8>> {
         let data = self.handshake_data().await?;
         match data.downcast::<quinn::crypto::rustls::HandshakeData>() {
             Ok(data) => match data.protocol {
-                Some(protocol) => std::string::String::from_utf8(protocol).map_err(Into::into),
+                Some(protocol) => Ok(protocol),
                 None => bail!("no ALPN protocol available"),
             },
             Err(_) => bail!("unknown handshake type"),
@@ -1365,7 +1365,7 @@ mod tests {
             let conn = incoming.await.unwrap();
             let node_id = get_remote_node_id(&conn).unwrap();
             assert_eq!(node_id, src);
-            assert_eq!(alpn.as_bytes(), TEST_ALPN);
+            assert_eq!(alpn, TEST_ALPN);
             let (mut send, mut recv) = conn.accept_bi().await.unwrap();
             let m = recv.read_to_end(100).await.unwrap();
             assert_eq!(m, b"hello");

iroh/src/node/builder.rs

@@ -734,12 +734,12 @@ impl Default for GcPolicy {
 #[allow(clippy::too_many_arguments)]
 async fn handle_connection<D: BaoStore>(
     connecting: iroh_net::endpoint::Connecting,
-    alpn: String,
+    alpn: Vec<u8>,
     node: Arc<NodeInner<D>>,
     gossip: Gossip,
     sync: DocsEngine,
 ) -> Result<()> {
-    match alpn.as_bytes() {
+    match alpn.as_ref() {
         GOSSIP_ALPN => gossip.handle_connection(connecting.await?).await?,
         DOCS_ALPN => sync.handle_connection(connecting).await?,
         alpn if alpn == iroh_blobs::protocol::ALPN => {