Don't send seqno requests to peers if they are already in the cache

Signed-off-by: Lee Smet <lee.smet@hotmail.com>

CHANGELOG.md

@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   with a TTL exceeded otherwise. This fixes an issue where packets with a TTL of
   1 and 0 originating locally would not result in a proper ICMP reply. This happens
   for instance when using `traceroute`.
+- Check the local seqno request cache before sending a seqno request to a peer,
+  to avoid spamming in certain occasions.
 
 ## [0.6.0] - 2025-04-25
 
@@ -551,7 +553,7 @@ This is a breaking change, check the main README file for update info.
 
 - Remove trailing 'e' character from release archive names
 
-## \[0.1.0\] - 2023-11-15
+## [0.1.0] - 2023-11-15
 
 ### Added
 

mycelium/src/router.rs

@@ -1493,7 +1493,18 @@ where
             }
         };
 
+        // Don't overload peers with request for the same source key
+        let already_received = self.seqno_cache.get(&srck).unwrap_or_default();
+
         for peer in targets {
+            if already_received.contains(&peer) {
+                trace!(
+                    peer = peer.connection_identifier(),
+                    "Don't send seqno request to peer which already received it recently"
+                );
+                continue;
+            }
+
             debug!(
                 "Sending seqno_request to {} for seqno {} of {}",
                 peer.connection_identifier(),