platform: Add link flags

experimental/libbox/link_flags_linux.go

@@ -0,0 +1,30 @@
+package libbox
+
+import (
+	"net"
+	"syscall"
+)
+
+// copied from net.linkFlags
+func linkFlags(rawFlags uint32) net.Flags {
+	var f net.Flags
+	if rawFlags&syscall.IFF_UP != 0 {
+		f |= net.FlagUp
+	}
+	if rawFlags&syscall.IFF_RUNNING != 0 {
+		f |= net.FlagRunning
+	}
+	if rawFlags&syscall.IFF_BROADCAST != 0 {
+		f |= net.FlagBroadcast
+	}
+	if rawFlags&syscall.IFF_LOOPBACK != 0 {
+		f |= net.FlagLoopback
+	}
+	if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+		f |= net.FlagPointToPoint
+	}
+	if rawFlags&syscall.IFF_MULTICAST != 0 {
+		f |= net.FlagMulticast
+	}
+	return f
+}

experimental/libbox/link_flags_stub.go

@@ -0,0 +1,11 @@
+//go:build !linux
+
+package libbox
+
+import (
+	"net"
+)
+
+func linkFlags(rawFlags uint32) net.Flags {
+	panic("stub!")
+}

experimental/libbox/platform.go

@@ -38,6 +38,7 @@ type NetworkInterface struct {
 	MTU       int32
 	Name      string
 	Addresses StringIterator
+	Flags     int32
 }
 
 type WIFIState struct {

experimental/libbox/service.go

@@ -181,6 +181,7 @@ func (w *platformInterfaceWrapper) Interfaces() ([]control.Interface, error) {
 			MTU:       int(netInterface.MTU),
 			Name:      netInterface.Name,
 			Addresses: common.Map(iteratorToArray[string](netInterface.Addresses), netip.MustParsePrefix),
+			Flags:     linkFlags(uint32(netInterface.Flags)),
 		})
 	}
 	return interfaces, nil