number handshakes

This prevents late hellos from resetting the session.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/transport/mod.rs b/src/transport/mod.rs
index b2ce63f..614ac48 100644
--- a/src/transport/mod.rs
+++ b/src/transport/mod.rs
@@ -256,6 +256,10 @@ pub struct HelloRequest {
     /// Random per run of the sender; the reply echoes it.
     #[serde(with = "crate::transport::wire::codec::run_id")]
     pub run_id: RunId,
+    /// The handshake's number: the sender numbers the handshakes it starts in a run,
+    /// with all peers, from 1. A retry carries the same number, so the recipient resets
+    /// its sync session only for a new handshake, not for every resend or late copy.
+    pub handshake: u32,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]