backup.in: honor ipv4/6 preference set in .ssh/config

1 files changed, 16 insertions, 1 deletions

diff --git a/backup.in b/backup.in
index eeafcdd..e8caa03 100755
--- a/backup.in
+++ b/backup.in
@@ -52,7 +52,22 @@ extract_ssh_ip_protocols() {
       t
       d
     ' \
-    | sort -u
+    | sort -u \
+    | if [ -f ~/.ssh/config ]; then
+      grep -vxF "$(
+        sed '
+          /^Host\s\+'"$1"'$/,/^Host\s/ {
+            s/^\s*AddressFamily\s\+inet\s*$/6/
+            t
+            s/^\s*AddressFamily\s\+inet6\s*$/4/
+            t
+          }
+          d
+        ' ~/.ssh/config
+      )"
+    else
+      cat
+    fi
 }
 
 if [ $# -eq 1 ]; then