源码快照 @ 2026-09-01 (source-only, 剔除非源码素材)

packages/device-link/internal/interfacebind/listen_darwin.go

@@ -0,0 +1,52 @@
+//go:build darwin
+
+package interfacebind
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+// ListenUDP opens a UDP socket pinned to one Darwin interface. Binding the
+// source address alone is insufficient when a utun route owns the destination;
+// IP_BOUND_IF keeps STUN, ICE checks, and application packets on the selected
+// physical path.
+func ListenUDP(ctx context.Context, network string, addr *net.UDPAddr, interfaceIndex int) (*net.UDPConn, error) {
+	if addr == nil || addr.IP == nil || addr.IP.IsUnspecified() {
+		return nil, fmt.Errorf("listen UDP on interface requires a concrete local address")
+	}
+	if interfaceIndex <= 0 {
+		return nil, fmt.Errorf("listen UDP on interface requires a positive interface index")
+	}
+	level := unix.IPPROTO_IPV6
+	option := unix.IPV6_BOUND_IF
+	if addr.IP.To4() != nil {
+		level = unix.IPPROTO_IP
+		option = unix.IP_BOUND_IF
+	}
+	var socketErr error
+	lc := net.ListenConfig{
+		Control: func(_, _ string, raw syscall.RawConn) error {
+			if err := raw.Control(func(fd uintptr) {
+				socketErr = unix.SetsockoptInt(int(fd), level, option, interfaceIndex)
+			}); err != nil {
+				return err
+			}
+			return socketErr
+		},
+	}
+	packetConn, err := lc.ListenPacket(ctx, network, addr.String())
+	if err != nil {
+		return nil, err
+	}
+	conn, ok := packetConn.(*net.UDPConn)
+	if !ok {
+		_ = packetConn.Close()
+		return nil, fmt.Errorf("listen UDP returned %T", packetConn)
+	}
+	return conn, nil
+}

packages/device-link/internal/interfacebind/listen_other.go

@@ -0,0 +1,29 @@
+//go:build !darwin
+
+package interfacebind
+
+import (
+	"context"
+	"fmt"
+	"net"
+)
+
+// ListenUDP keeps the shared interface explicit on non-Darwin builds. The
+// first release only exposes direct physical routing on macOS; other platforms
+// retain source-address binding until they grow a native interface option.
+func ListenUDP(ctx context.Context, network string, addr *net.UDPAddr, _ int) (*net.UDPConn, error) {
+	if addr == nil || addr.IP == nil || addr.IP.IsUnspecified() {
+		return nil, fmt.Errorf("listen UDP on interface requires a concrete local address")
+	}
+	lc := net.ListenConfig{}
+	packetConn, err := lc.ListenPacket(ctx, network, addr.String())
+	if err != nil {
+		return nil, err
+	}
+	conn, ok := packetConn.(*net.UDPConn)
+	if !ok {
+		_ = packetConn.Close()
+		return nil, fmt.Errorf("listen UDP returned %T", packetConn)
+	}
+	return conn, nil
+}