TUN-6592: Decrement TTL and return ICMP time exceed if it's 0

ingress/icmp_generic.go

@@ -3,14 +3,29 @@
 package ingress
 
 import (
+	"context"
 	"fmt"
 	"net/netip"
 	"runtime"
 	"time"
 
 	"github.com/rs/zerolog"
+
+	"github.com/cloudflare/cloudflared/packet"
 )
 
-func newICMPProxy(listenIP netip.Addr, logger *zerolog.Logger, idleTimeout time.Duration) (ICMPProxy, error) {
-	return nil, fmt.Errorf("ICMP proxy is not implemented on %s", runtime.GOOS)
+var errICMPProxyNotImplemented = fmt.Errorf("ICMP proxy is not implemented on %s", runtime.GOOS)
+
+type icmpProxy struct{}
+
+func (ip icmpProxy) Request(pk *packet.ICMP, responder packet.FunnelUniPipe) error {
+	return errICMPProxyNotImplemented
+}
+
+func (ip *icmpProxy) Serve(ctx context.Context) error {
+	return errICMPProxyNotImplemented
+}
+
+func newICMPProxy(listenIP netip.Addr, logger *zerolog.Logger, idleTimeout time.Duration) (*icmpProxy, error) {
+	return nil, errICMPProxyNotImplemented
 }