From b2be4c2cb7b68c0010d3076fa0eaa43c88fab2ed Mon Sep 17 00:00:00 2001
From: DuProcess <273172371+DuProcess@users.noreply.github.com>
Date: Sat, 11 Jul 2026 12:15:25 -0400
Subject: [PATCH] Retry transport receive during UDP churn

---
 Cargo.lock       |  2 +-
 Cargo.toml       |  2 +-
 src/transport.rs | 41 +++++++++++++++++++++++++++++++++++++++--
 3 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index ec94b64..7539687 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -436,7 +436,7 @@ dependencies = [
 
 [[package]]
 name = "dosh"
-version = "1.0.0-rc21"
+version = "1.0.0-rc22"
 dependencies = [
  "anyhow",
  "base64",
diff --git a/Cargo.toml b/Cargo.toml
index 4e26c23..dd88e34 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "dosh"
-version = "1.0.0-rc21"
+version = "1.0.0-rc22"
 edition = "2024"
 license = "MIT"
 
diff --git a/src/transport.rs b/src/transport.rs
index 71e5f42..93916dd 100644
--- a/src/transport.rs
+++ b/src/transport.rs
@@ -19,7 +19,7 @@ use crate::protocol::{
     self, CLIENT_TO_SERVER, PacketKind, ReplayWindow, SERVER_TO_CLIENT, StreamClose, StreamData,
     StreamOpen, StreamOpenOk, StreamOpenReject, StreamWindowAdjust,
 };
-use crate::udp::is_transient_udp_send_error;
+use crate::udp::{is_transient_udp_error, is_transient_udp_send_error};
 use anyhow::{Result, anyhow, bail};
 use std::collections::{BTreeMap, HashMap, HashSet, VecDeque};
 use std::net::SocketAddr;
@@ -852,7 +852,11 @@ impl DoshTransport {
     pub async fn recv(&mut self) -> Result<SessionEvent> {
         let mut buf = vec![0u8; 65535];
         loop {
-            let (n, peer) = self.socket.recv_from(&mut buf).await?;
+            let (n, peer) = match self.socket.recv_from(&mut buf).await {
+                Ok(value) => value,
+                Err(err) if transport_recv_error_is_retryable(&err) => continue,
+                Err(err) => return Err(err.into()),
+            };
             let packet = match protocol::decode(&buf[..n]) {
                 Ok(packet) => packet,
                 Err(_) => continue,
@@ -984,6 +988,10 @@ impl DoshTransport {
     }
 }
 
+fn transport_recv_error_is_retryable(err: &std::io::Error) -> bool {
+    is_transient_udp_error(err)
+}
+
 fn initial_stream_id(role: SessionRole) -> u64 {
     match role {
         SessionRole::Client => 1,
@@ -1033,6 +1041,35 @@ mod tests {
         assert!(service_target("../bad").is_err());
     }
 
+    #[test]
+    fn transport_recv_retries_network_churn_errors() {
+        for kind in [
+            std::io::ErrorKind::Interrupted,
+            std::io::ErrorKind::TimedOut,
+            std::io::ErrorKind::WouldBlock,
+        ] {
+            let err = std::io::Error::from(kind);
+            assert!(transport_recv_error_is_retryable(&err));
+        }
+        assert!(!transport_recv_error_is_retryable(&std::io::Error::from(
+            std::io::ErrorKind::PermissionDenied,
+        )));
+
+        #[cfg(unix)]
+        for code in [libc::ENETUNREACH, libc::EHOSTUNREACH, libc::ECONNRESET] {
+            assert!(transport_recv_error_is_retryable(
+                &std::io::Error::from_raw_os_error(code)
+            ));
+        }
+
+        #[cfg(windows)]
+        for code in [10051, 10054, 10065] {
+            assert!(transport_recv_error_is_retryable(
+                &std::io::Error::from_raw_os_error(code)
+            ));
+        }
+    }
+
     #[test]
     fn service_registry_matches_registered_service_opens() {
         let mut registry = ServiceRegistry::new();