iptables: use "-t nat" for NAT tests

PiperOrigin-RevId: 295835807

2 files changed, 12 insertions, 3 deletions

diff --git a/test/iptables/iptables_util.go b/test/iptables/iptables_util.go
index 293c4e6ed..32cf5a417 100644
--- a/test/iptables/iptables_util.go
+++ b/test/iptables/iptables_util.go
@@ -27,7 +27,16 @@ const iptablesBinary = "iptables"
 
 // filterTable calls `iptables -t filter` with the given args.
 func filterTable(args ...string) error {
-	args = append([]string{"-t", "filter"}, args...)
+	return tableCmd("filter", args)
+}
+
+// natTable calls `iptables -t nat` with the given args.
+func natTable(args ...string) error {
+	return tableCmd("nat", args)
+}
+
+func tableCmd(table string, args []string) error {
+	args = append([]string{"-t", table}, args...)
 	cmd := exec.Command(iptablesBinary, args...)
 	if out, err := cmd.CombinedOutput(); err != nil {
 		return fmt.Errorf("error running iptables with args %v\nerror: %v\noutput: %s", args, err, string(out))
diff --git a/test/iptables/nat.go b/test/iptables/nat.go
index b5c6f927e..a01117ec8 100644
--- a/test/iptables/nat.go
+++ b/test/iptables/nat.go
@@ -38,7 +38,7 @@ func (NATRedirectUDPPort) Name() string {
 
 // ContainerAction implements TestCase.ContainerAction.
 func (NATRedirectUDPPort) ContainerAction(ip net.IP) error {
-	if err := filterTable("-t", "nat", "-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil {
+	if err := natTable("-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil {
 		return err
 	}
 
@@ -63,7 +63,7 @@ func (NATDropUDP) Name() string {
 
 // ContainerAction implements TestCase.ContainerAction.
 func (NATDropUDP) ContainerAction(ip net.IP) error {
-	if err := filterTable("-t", "nat", "-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil {
+	if err := natTable("-A", "PREROUTING", "-p", "udp", "-j", "REDIRECT", "--to-ports", fmt.Sprintf("%d", redirectPort)); err != nil {
 		return err
 	}