From 0afbca8e4fb60c2cb4c5f6dc2e1f9c6d7366bdcc Mon Sep 17 00:00:00 2001
From: Johannes Truschnigg <johannes@truschnigg.info>
Date: Tue, 15 Mar 2022 12:21:08 +0100
Subject: [PATCH] Add helper script to determine the first ICMP ECHOing hop

---
 reflector_detect | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100755 reflector_detect

diff --git a/reflector_detect b/reflector_detect
new file mode 100755
index 0000000..63903ba
--- /dev/null
+++ b/reflector_detect
@@ -0,0 +1,26 @@
+#!/bin/sh
+
+get_first_pingpeer() {
+  traceroute -n "${1}" | while read num peer lat1 _ lat2 _ lat3 _
+  do
+    case "${num}" in
+      [123456789]*)
+        if ping -c 1 -s 1280 -W 2 -w 2 "${peer}" >/dev/null 2>/dev/null
+        then
+          printf '# %s - hop #%d (%s) responds to ICMP ECHO\n' "${1}" "${num}" "${peer}"
+          printf 'PEER %s\n' "${peer}"
+          break
+        fi
+      ;;
+      *)
+        : pass $num $peer
+      ;;
+    esac
+  done
+}
+
+
+for p in 8.8.8.8 1.1.1.1 example.com google.com
+do
+  get_first_pingpeer "${p}"
+done
-- 
2.39.5