From 6f0227a6ee5cc1887c9045e659a9a06d75b51f53 Mon Sep 17 00:00:00 2001
From: Martin Winkler <efelon@winklerfamilie.eu>
Date: Thu, 1 Apr 2021 14:12:59 +0200
Subject: [PATCH] Enhanced public ip detection

First try with upnpc to acquire ip via router, then fallback to extrenal dns query
---
 seqs/coturn.sh | 45 ++++++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/seqs/coturn.sh b/seqs/coturn.sh
index 2a82934..5f36b1b 100755
--- a/seqs/coturn.sh
+++ b/seqs/coturn.sh
@@ -1,8 +1,10 @@
 #!/bin/bash
 
 toolName=coturn
+toolDeps="coturn miniupnpc"
 toolConf="/etc/turnserver.conf"
 toolServiceName="coturn.service"
+publicIpRetry=20
 
 # Get script working directory
 # (when called from a different directory)
@@ -36,40 +38,57 @@ step_1_info() { echo "Install $toolName"; }
 step_1_alias() { ALIAS="install"; }
 step_1() {
   exe apt update
-  exe apt install coturn $APTOPT
+  exe apt install $toolDeps $APTOPT
 }
 
 step_10_info() {
   echo "Update $toolName 'external-ip' using dig [OPTION] [CUSTOM DNS]"
   echoinfo " [OPTION]"
-  echoinfo "   -l  :  Always output informations (even with -qq)"
+  echoinfo "   -l  :  Always output update required and error information"
+  echoinfo "          (even with -qq)"
 }
 step_10_alias() { ALIAS="updateip"; }
 step_10() {
+  exitIfRunning
   shift
+  local retryCount=$publicIpRetry
+  local ipUpdater
+  local ipRegex='^[0-2]*[0-9]{1,2}\.[0-2]*[0-9]{1,2}\.[0-2]*[0-9]{1,2}\.[0-2]*[0-9]{1,2}\/*[0-9]*$'
+  local dnsUrl="46.182.19.48" #digitalcourage.de/support/zensurfreier-dns-server
+  local dnsFallbackUrl="194.150.168.168" #dns.as250.net; Berlin/Frankfurt
   local lecho="echoseq"
   if [ "$1" == "-l" ]; then
     lecho="echo"
     shift
   fi
-
-  local dnsUrl="46.182.19.48" #digitalcourage.de/support/zensurfreier-dns-server
-  [ ! -z "$1" ] && dnsUrl="$1"
   
-  local pubIp=$(dig @$dnsUrl +short cloud.imoff.de)
+  local pubIp
+
+  while [ $retryCount -gt 0 ]; do
+    pubIp=`"$(command -v upnpc)" -s | grep ^ExternalIPAddress | cut -c21-`
+    [ $? -eq 0 ] && ipUpdater="upnpc" && break || "$lecho" "[$(date)] [W] Upnpc failed"
+    pubIp=$(dig @$dnsUrl +short +timeout=1 cloud.imoff.de 2>>/dev/null)
+    [ $? -eq 0 ] && ipUpdater="DNS" && break || "$lecho" "[$(date) [W] DNS lookup to $dnsUrl failed"
+    pubIp=$(dig @$dnsFallbackUrl +short +timeout=1 cloud.imoff.de 2>>/dev/null)
+    [ $? -eq 0 ] && ipUpdater="DNS Fallback" && break || "$lecho" "[$(date)] [W] DNS lookup to $dnsFallbackUrl failed"
+    ((retryCount--))
+  done
+
+  if [[ ! $pubIp =~ $ipRegex ]]; then
+    "$lecho" "[$(date)] [E] Couldn't aquire public IP. Giving up."
+    return 1
+  fi
+
   local confIp=`cat "$toolConf" | grep "^external-ip" | cut -d'=' -f2`
-  local locDate=`date`
 
   if [ "$pubIp" != "$confIp" ]; then
-    $lecho " [I] Update required. New public ip: $pubIp"
-    $lecho "     $locDate"
+    $lecho "[$(date)] [I] Update required (via $ipUpdater). New public ip: $pubIp"
     exe sed -i "s/^external-ip[[:space:]]*=.*/external-ip=${pubIp}/" "$toolConf"
     exe sleep 1
-    $lecho " [I] Restarting $toolName"
+    $lecho "[$(date)] [I] Restarting $toolName"
     exe /bin/systemctl restart $toolServiceName
   else
-    echoseq " [I] No update required. Current ip: $confIp"
-    echoseq "     $locDate"
+    echoseq "[$(date)] [I] No update required (via $ipUpdater). Current ip: $confIp"
   fi
 }
 
@@ -82,5 +101,5 @@ step_12() {
 ipCronLoc="/etc/cron.d/update_public_ip"
 ipCron="*/5 * * * * root $WDIR/$SCRIPT_FILE -qq updateip"
 
-VERSION_SEQREV=12
+VERSION_SEQREV=13
 . /usr/local/bin/sequencer.sh