backup.in: ignore ip versions with which we are not connected

1 files changed, 20 insertions, 2 deletions

diff --git a/backup.in b/backup.in
index 6c3c774..b74487a 100755
--- a/backup.in
+++ b/backup.in
@@ -70,6 +70,19 @@ extract_ssh_ip_protocols() {
     fi
 }
 
+connected_ip_versions() {
+  ip -o addr show scope global \
+    | awk '{print $4}' \
+    | sed '
+      s@^\([0-9]\+\.\)\{3\}[0-9]\+\(/[0-9]\+\)\?$@4@
+      t
+      s@^[0-9a-f][0-9a-f:]\+\(/[0-9]\+\)\?$@6@
+      t
+      d
+    ' \
+    | sort -u
+}
+
 if [ $# -eq 1 ]; then
   if [ "$1" == "--help" ]; then
     usage 0
@@ -101,8 +114,13 @@ QuellIP=$(echo "$3" | sed "s|^[a-zA-Z]*://||; s|^[a-zA-Z]*@||; s|:\?/.*$||")
 if [ "$#" -eq 3 ]; then
   Quelle="$3"
   ipVer=$(
-    extract_ssh_ip_protocols "${QuellIP}" \
-      | sort -n \
+    {
+      extract_ssh_ip_protocols "${QuellIP}" \
+        | sort -n
+      extract_ssh_ip_protocols "${QuellIP}" \
+        | grep -xF "$(connected_ip_versions)" \
+        | sort -n
+    } \
       | tail -n1
   )
 elif [ "$#" -eq 4 ]; then