Export interface for WireGuard

stack_system_packet.go

@@ -0,0 +1,34 @@
+package tun
+
+import (
+	"net/netip"
+	"syscall"
+
+	"github.com/sagernet/sing-tun/internal/gtcpip/header"
+)
+
+func PacketIPVersion(packet []byte) int {
+	return header.IPVersion(packet)
+}
+
+func PacketFillHeader(packet []byte, ipVersion int) {
+	if PacketOffset > 0 {
+		switch ipVersion {
+		case header.IPv4Version:
+			packet[3] = syscall.AF_INET
+		case header.IPv6Version:
+			packet[3] = syscall.AF_INET6
+		}
+	}
+}
+
+func PacketDestination(packet []byte) netip.Addr {
+	switch ipVersion := header.IPVersion(packet); ipVersion {
+	case header.IPv4Version:
+		return header.IPv4(packet).DestinationAddr()
+	case header.IPv6Version:
+		return header.IPv6(packet).DestinationAddr()
+	default:
+		return netip.Addr{}
+	}
+}