From 7b220dab8d1058fd00b67fd46aef955f4add8f2a Mon Sep 17 00:00:00 2001
From: Minecon724 <minecon724@noreply.git.m724.eu>
Date: Sat, 11 Jan 2025 20:40:39 +0100
Subject: [PATCH] Add pingfinder.sh

---
 pingfinder.sh | 136 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 136 insertions(+)
 create mode 100644 pingfinder.sh

diff --git a/pingfinder.sh b/pingfinder.sh
new file mode 100644
index 0000000..a9f386c
--- /dev/null
+++ b/pingfinder.sh
@@ -0,0 +1,136 @@
+#!/usr/bin/env bash
+#
+# Measurement script for the dn42 peer finder, see http://dn42.us/peers
+# Dependencies: curl, sed, ping
+#
+# This script is designed to be run in cron every 5 minutes, like this:
+#
+#   UUID=<Your UUID goes here>
+#   */5 * * * * /home/foo/cron.sh
+#
+
+# Put your UUID here, and keep it secret!
+# shellcheck disable=SC2269 # Intended assignment of UUID
+UUID=${UUID}
+PEERFINDER=${PEERFINDER:-"https://dn42.us/peers"}
+NB_PINGS=${NB_PINGS:-5}
+LOGFILE=${LOGFILE:-/dev/stdout}   # Set to /dev/null to only receive errors.
+                                  # Set to a file writable by the cron runner to record pings.
+                                  #  (Errors will be sent in cron mail)
+WARNLOCK=${WARNLOCK:-warn.lock}   # Set this variable if you want a file written when the script updates.
+LOCKFILE=${LOCKFILE:-exec.lock}   # Set this variable if you want the script to not run multiple instances at once.
+LOCKFD=${LOCKFD:-42}
+
+# This avoids synchronisation (everybody fetching jobs and running
+# measurements simultaneously)
+# RANDOM_DELAY=30
+# SLEEP=$((RANDOM % RANDOM_DELAY))
+# sleep "$SLEEP"
+
+function die() {
+  echo "## PEERFINDER ERROR $(date) ## " \
+    "$*"
+  exit 1
+}
+
+eval "exec $LOCKFD>$LOCKFILE"
+
+flock -n "$LOCKFD" || die "Unable to acquire lock."
+
+VERSION=1.2.1
+# shellcheck disable=SC2046 # Intended splitting of VERSION
+# shellcheck disable=SC2183 #
+ver() { printf "%03d%03d%03d%03d" $(echo "$1" | tr '.' ' '); }
+
+[ -e "$LOGFILE" ] || touch "$LOGFILE"
+exec >> "$LOGFILE"
+
+echo "STARTING PEERFINDER (v. $VERSION)"
+
+# check for IPv4 binary
+PING4=$(which ping)
+
+# check for IPv6 binary. if ping6 is missing assume 'ping -6'
+PING6=$(which ping6)
+[ -z "$PING6" ] && [ -n "$PING4" ] && PING6="$PING4 -6"
+
+CURL=$(which curl)
+if [ -z "$CURL" ]; then
+  die "Unable to find a suitable curl binary."
+fi
+CURL="$CURL -A PeerFinder -sf"
+
+while true ; do
+
+  JOB=$(mktemp)
+
+  $CURL -H 'accept: text/environment' "$PEERFINDER/pending/$UUID" | tee "$JOB"
+
+  REQ_ID=$(grep REQ_ID "$JOB"|cut -d'=' -f2|tr -d '[$`;><{}%|&!()]"\\/')
+  REQ_IP=$(grep REQ_IP "$JOB"|cut -d'=' -f2|tr -d '[$`;><{}%|&!()]"\\/')
+  REQ_FAMILY=$(grep REQ_FAMILY "$JOB"|cut -d'=' -f2|tr -d '[$`;><{}%|&!()]"\\/')
+  CUR_VERSION=$(grep SCRIPT_VERSION "$JOB"|cut -d'=' -f2|tr -d '[$`;><{}%|&!()]"\\/')
+
+  rm "$JOB"
+
+  if [ "$(ver "$VERSION")" -lt "$(ver "$CUR_VERSION")" ]; then
+    echo "## PEERFINDER WARN $(date) ## " \
+         "Current script version is $CUR_VERSION. You are running $VERSION " \
+         "Get it here: https://dn42.us/peers/script"
+
+    [ -z "$WARNLOCK" ] && touch "$WARNLOCK"
+  else
+    [ -z "$WARNLOCK" ] || [ -f "$WARNLOCK" ] && rm "$WARNLOCK"
+  fi
+
+  # Avoid empty fields
+  [ -z "$REQ_ID" ] && [ -z "$REQ_IP" ] && exit
+
+  [ "$REQ_FAMILY" -eq "1" ] && [ -n "$PING4" ] && PING="ping -n -q"
+  [ "$REQ_FAMILY" -eq "2" ] && [ -n "$PING6" ] && PING="$PING6 -n -q"
+
+  if [ -z "$PING" ]; then
+    die "Unable to find a suitable ping binary."
+  fi
+
+  echo "PINGING TO: $REQ_IP for $REQ_ID..."
+
+  # Parsing ping output, for Linux
+  if ! output=$($PING -c "$NB_PINGS" "$REQ_IP" 2>&1 | grep -A1 "packets transmitted"); then
+    sent=0
+    received=0
+    args="res_latency=NULL"
+    echo "Target $REQ_ID ($REQ_IP) is unreachable"
+  else
+     pattern='([0-9]*) packets transmitted, ([0-9]*)( packets)? received'
+     if [[ $output =~ $pattern ]]; then
+         sent=${BASH_REMATCH[1]}
+         received=${BASH_REMATCH[2]}
+         if [ "$received" -eq 0 ]
+         then
+             args="res_latency=NULL"
+             echo "Target $REQ_ID ($REQ_IP) is unreachable"
+         else
+             pattern='(rtt|round-trip) min\/avg\/max.*= ([.0-9]+)\/([.0-9]+)\/([.0-9]+)\/?([.0-9]+)? ms'
+             if [[ $output =~ $pattern ]]; then
+                 minrtt=${BASH_REMATCH[2]}
+                 avgrtt=${BASH_REMATCH[3]}
+                 maxrtt=${BASH_REMATCH[4]}
+                 jitter=${BASH_REMATCH[5]}
+                 [ -z "$avgrtt" ] && exit
+                 echo "RTT to target $REQ_ID ($REQ_IP) is $avgrtt"
+                 args="res_latency=${avgrtt}&res_jitter=${jitter}&res_minrtt=${minrtt}&res_maxrtt=${maxrtt}&res_sent=${sent}&res_recv=${received}"
+             else
+                 args="res_latency=NULL"
+             fi
+         fi
+      else
+          args="res_latency=NULL"
+      fi
+  fi
+
+  # Report results back to peerfinder
+  echo "RESULT $args"
+  $CURL -X POST "$PEERFINDER/req/$REQ_ID" -d "peer_id=$UUID&peer_version=$VERSION&$args" -H 'accept: text/environment'
+
+done