Files
2026-07-09 11:20:33 +08:00

139 lines
4.1 KiB
Go

package bridge
import (
"context"
"net"
"net/netip"
"slices"
"github.com/sagernet/sing-box/adapter"
"github.com/sagernet/sing-box/adapter/outbound"
C "github.com/sagernet/sing-box/constant"
"github.com/sagernet/sing-box/log"
"github.com/sagernet/sing-box/option"
"github.com/sagernet/sing-tun"
E "github.com/sagernet/sing/common/exceptions"
M "github.com/sagernet/sing/common/metadata"
N "github.com/sagernet/sing/common/network"
"github.com/sagernet/sing/service"
)
func RegisterOutbound(registry *outbound.Registry) {
outbound.Register[option.BridgeOutboundOptions](registry, C.TypeBridge, NewOutbound)
}
var (
_ adapter.Outbound = (*Outbound)(nil)
_ adapter.FlowOutbound = (*Outbound)(nil)
_ adapter.OutboundWithPreferredRoutes = (*Outbound)(nil)
_ adapter.Lifecycle = (*Outbound)(nil)
)
type Backend interface {
adapter.Lifecycle
tun.Port
}
type Outbound struct {
outbound.Adapter
logger log.ContextLogger
networkManager adapter.NetworkManager
platformInterface adapter.PlatformInterface
backend Backend
}
func NewOutbound(ctx context.Context, router adapter.Router, logger log.ContextLogger, tag string, options option.BridgeOutboundOptions) (adapter.Outbound, error) {
networkManager := service.FromContext[adapter.NetworkManager](ctx)
outboundBackend, err := newBackend(ctx, logger, networkManager, tag, options)
if err != nil {
return nil, err
}
return &Outbound{
Adapter: outbound.NewAdapter(C.TypeBridge, tag, []string{N.NetworkTCP, N.NetworkUDP, N.NetworkICMP}, nil),
logger: logger,
networkManager: networkManager,
platformInterface: service.FromContext[adapter.PlatformInterface](ctx),
backend: outboundBackend,
}, nil
}
func (o *Outbound) Start(stage adapter.StartStage) error {
return o.backend.Start(stage)
}
func (o *Outbound) Close() error {
return o.backend.Close()
}
func (o *Outbound) PreferredDomain(metadata *adapter.InboundContext, domain string) bool {
return false
}
func (o *Outbound) PreferredAddress(metadata *adapter.InboundContext, address netip.Addr) bool {
return metadata.PreMatch && !o.isLocalDestination(address)
}
func (o *Outbound) PreMatchFlow(network string, destination netip.Addr) adapter.PreMatchAction {
if o.isLocalDestination(destination) {
o.logger.Warn("rejected connection to local destination ", destination, ": traffic to local addresses is not supported by bridge, exclude them in route rules")
return adapter.PreMatchReject
}
return adapter.PreMatchFlow
}
func (o *Outbound) isLocalDestination(destination netip.Addr) bool {
if !destination.IsValid() {
return false
}
destination = destination.Unmap()
if destination.IsLoopback() || destination.IsUnspecified() {
return true
}
if o.platformInterface != nil && slices.Contains(o.platformInterface.MyInterfaceAddress(), destination) {
return true
}
for _, netInterface := range o.networkManager.InterfaceFinder().Interfaces() {
for _, prefix := range netInterface.Addresses {
if prefix.Addr() == destination {
return true
}
}
}
return false
}
func (o *Outbound) PortAddresses() (netip.Addr, netip.Addr) {
return o.backend.PortAddresses()
}
func (o *Outbound) PortMTU() uint32 {
return o.backend.PortMTU()
}
func (o *Outbound) PortSelectorRange() (uint16, uint16) {
if rangedBackend, isRanged := o.backend.(tun.PortWithSelectorRange); isRanged {
return rangedBackend.PortSelectorRange()
}
return 0, 0
}
func (o *Outbound) AttachReturn(returnPath tun.Return) error {
return o.backend.AttachReturn(returnPath)
}
func (o *Outbound) DetachReturn(returnPath tun.Return) error {
return o.backend.DetachReturn(returnPath)
}
func (o *Outbound) WritePackets(packets [][]byte) error {
return o.backend.WritePackets(packets)
}
func (o *Outbound) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
return nil, E.New("only L3 traffic is supported by bridge")
}
func (o *Outbound) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
return nil, E.New("only L3 traffic is supported by bridge")
}