From 751981c31818f8eaf4dc21dc1977daabc099c047 Mon Sep 17 00:00:00 2001
From: Murali Reddy <muralimmreddy@gmail.com>
Date: Mon, 28 Jun 2021 02:53:41 +0530
Subject: [PATCH] update alpine image to 3.14 for latest iptables-restore
 command with --wait option, and use wait where its available

---
 Dockerfile            |  2 +-
 pkg/utils/iptables.go | 22 +++++++++++++++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 1e8d1482..9c43d5e9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,5 +1,5 @@
 ARG ARCH=
-FROM ${ARCH}alpine:3.12
+FROM ${ARCH}alpine:3.14
 
 RUN apk add --no-cache \
       iptables \
diff --git a/pkg/utils/iptables.go b/pkg/utils/iptables.go
index 3919f432..8fb5c879 100644
--- a/pkg/utils/iptables.go
+++ b/pkg/utils/iptables.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"os/exec"
+	"strings"
 )
 
 // SaveInto calls `iptables-save` for given table and stores result in a given buffer.
@@ -32,15 +33,30 @@ func Restore(table string, data []byte) error {
 	if err != nil {
 		return err
 	}
-	args := []string{"iptables-restore", "-T", table}
+	var args []string
+	args = []string{"iptables-restore", "--help"}
 	cmd := exec.Cmd{
+		Path: path,
+		Args: args,
+	}
+	cmdOutput, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("%v (%s)", err, cmdOutput)
+	}
+	if strings.Contains(string(cmdOutput), "wait") {
+		args = []string{"iptables-restore", "--wait", "-T", table}
+	} else {
+		args = []string{"iptables-restore", "-T", table}
+	}
+
+	cmd = exec.Cmd{
 		Path:  path,
 		Args:  args,
 		Stdin: bytes.NewBuffer(data),
 	}
-	b, err := cmd.CombinedOutput()
+	cmdOutput, err = cmd.CombinedOutput()
 	if err != nil {
-		return fmt.Errorf("%v (%s)", err, b)
+		return fmt.Errorf("%v (%s)", err, cmdOutput)
 	}
 
 	return nil