From 5b93d1023dadca05e716cb02bdb0df8e5584eda6 Mon Sep 17 00:00:00 2001
From: Lloyd <lloyd@rightup.co.uk>
Date: Thu, 21 May 2026 12:29:21 +0100
Subject: [PATCH] fix: update loop detection thresholds and improve path hash
 handling in API endpoints

---
 repeater/engine.py            | 10 ++++++++--
 repeater/web/api_endpoints.py |  4 +++-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/repeater/engine.py b/repeater/engine.py
index 6bf0aaf..0ca401f 100644
--- a/repeater/engine.py
+++ b/repeater/engine.py
@@ -36,7 +36,7 @@ LOOP_DETECT_MINIMAL = "minimal"
 LOOP_DETECT_MODERATE = "moderate"
 LOOP_DETECT_STRICT = "strict"
 
-# Thresholds for 1-byte path hashes loop detection.
+# Thresholds for flood loop detection (hash-size-aware: 1, 2, or 3 bytes per hop).
 # Count how many times our own hash already exists in the incoming FLOOD path.
 # If occurrences >= threshold, treat as loop and drop.
 LOOP_DETECT_MAX_COUNTERS = {
@@ -742,8 +742,14 @@ class RepeaterHandler(BaseHandler):
         if max_counter is None:
             return False
 
+        hash_size = packet.get_path_hash_size()
+        hop_count = packet.get_path_hash_count()
         path = packet.path or bytearray()
-        local_count = sum(1 for hop in path if hop == self.local_hash)
+        local_hash = self.local_hash_bytes[:hash_size]
+        local_count = sum(
+            1 for i in range(hop_count)
+            if bytes(path[i * hash_size:(i + 1) * hash_size]) == local_hash
+        )
         return local_count >= max_counter
 
     def _check_transport_codes(self, packet: Packet) -> Tuple[bool, str]:
diff --git a/repeater/web/api_endpoints.py b/repeater/web/api_endpoints.py
index 189d029..10b3733 100644
--- a/repeater/web/api_endpoints.py
+++ b/repeater/web/api_endpoints.py
@@ -2718,6 +2718,8 @@ class APIEndpoints:
             # 0 = 1-byte (legacy), 1 = 2-byte, 2 = 3-byte
             path_hash_mode = self.config.get("mesh", {}).get("path_hash_mode", 0)
             byte_count = {0: 1, 1: 2, 2: 3}.get(path_hash_mode, 1)
+
+            trace_flags = {1: 0x00, 2: 0x01}.get(byte_count, 0x00)
             hex_chars = byte_count * 2
             max_hash = (1 << (byte_count * 8)) - 1
 
@@ -2752,7 +2754,7 @@ class APIEndpoints:
 
             path_bytes = list(target_hash.to_bytes(byte_count, "big"))
             packet = PacketBuilder.create_trace(
-                tag=trace_tag, auth_code=0x12345678, flags=0x00, path=path_bytes
+                tag=trace_tag, auth_code=0x12345678, flags=trace_flags, path=path_bytes
             )
 
             # Wait for response with timeout