sing-box/outbound/direct.go
2024-05-21 15:11:52 +08:00

171 lines
5.7 KiB
Go

package outbound
import (
"context"
"net"
"net/netip"
"time"
"github.com/sagernet/sing-box/adapter"
"github.com/sagernet/sing-box/common/dialer"
C "github.com/sagernet/sing-box/constant"
"github.com/sagernet/sing-box/log"
"github.com/sagernet/sing-box/option"
"github.com/sagernet/sing-dns"
"github.com/sagernet/sing/common/bufio"
E "github.com/sagernet/sing/common/exceptions"
M "github.com/sagernet/sing/common/metadata"
N "github.com/sagernet/sing/common/network"
)
var (
_ adapter.Outbound = (*Direct)(nil)
_ N.ParallelDialer = (*Direct)(nil)
)
type Direct struct {
myOutboundAdapter
dialer N.Dialer
domainStrategy dns.DomainStrategy
fallbackDelay time.Duration
overrideOption int
overrideDestination M.Socksaddr
loopBack *loopBackDetector
}
func NewDirect(router adapter.Router, logger log.ContextLogger, tag string, options option.DirectOutboundOptions) (*Direct, error) {
options.UDPFragmentDefault = true
outboundDialer, err := dialer.New(router, options.DialerOptions)
if err != nil {
return nil, err
}
outbound := &Direct{
myOutboundAdapter: myOutboundAdapter{
protocol: C.TypeDirect,
network: []string{N.NetworkTCP, N.NetworkUDP},
router: router,
logger: logger,
tag: tag,
dependencies: withDialerDependency(options.DialerOptions),
},
domainStrategy: dns.DomainStrategy(options.DomainStrategy),
fallbackDelay: time.Duration(options.FallbackDelay),
dialer: outboundDialer,
loopBack: newLoopBackDetector(router),
}
if options.ProxyProtocol != 0 {
return nil, E.New("Proxy Protocol is deprecated and removed in sing-box 1.6.0")
}
if options.OverrideAddress != "" && options.OverridePort != 0 {
outbound.overrideOption = 1
outbound.overrideDestination = M.ParseSocksaddrHostPort(options.OverrideAddress, options.OverridePort)
} else if options.OverrideAddress != "" {
outbound.overrideOption = 2
outbound.overrideDestination = M.ParseSocksaddrHostPort(options.OverrideAddress, options.OverridePort)
} else if options.OverridePort != 0 {
outbound.overrideOption = 3
outbound.overrideDestination = M.Socksaddr{Port: options.OverridePort}
}
return outbound, nil
}
func (h *Direct) DialContext(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
ctx, metadata := adapter.AppendContext(ctx)
metadata.Outbound = h.tag
metadata.Destination = destination
switch h.overrideOption {
case 1:
destination = h.overrideDestination
case 2:
newDestination := h.overrideDestination
newDestination.Port = destination.Port
destination = newDestination
case 3:
destination.Port = h.overrideDestination.Port
}
network = N.NetworkName(network)
switch network {
case N.NetworkTCP:
h.logger.InfoContext(ctx, "outbound connection to ", destination)
case N.NetworkUDP:
h.logger.InfoContext(ctx, "outbound packet connection to ", destination)
}
conn, err := h.dialer.DialContext(ctx, network, destination)
if err != nil {
return nil, err
}
return h.loopBack.NewConn(conn), nil
}
func (h *Direct) DialParallel(ctx context.Context, network string, destination M.Socksaddr, destinationAddresses []netip.Addr) (net.Conn, error) {
ctx, metadata := adapter.AppendContext(ctx)
metadata.Outbound = h.tag
metadata.Destination = destination
switch h.overrideOption {
case 1, 2:
// override address
return h.DialContext(ctx, network, destination)
case 3:
destination.Port = h.overrideDestination.Port
}
network = N.NetworkName(network)
switch network {
case N.NetworkTCP:
h.logger.InfoContext(ctx, "outbound connection to ", destination)
case N.NetworkUDP:
h.logger.InfoContext(ctx, "outbound packet connection to ", destination)
}
var domainStrategy dns.DomainStrategy
if h.domainStrategy != dns.DomainStrategyAsIS {
domainStrategy = h.domainStrategy
} else {
domainStrategy = dns.DomainStrategy(metadata.InboundOptions.DomainStrategy)
}
return N.DialParallel(ctx, h.dialer, network, destination, destinationAddresses, domainStrategy == dns.DomainStrategyPreferIPv6, h.fallbackDelay)
}
func (h *Direct) ListenPacket(ctx context.Context, destination M.Socksaddr) (net.PacketConn, error) {
ctx, metadata := adapter.ExtendContext(ctx)
metadata.Outbound = h.tag
metadata.Destination = destination
originDestination := destination
switch h.overrideOption {
case 1:
destination = h.overrideDestination
case 2:
newDestination := h.overrideDestination
newDestination.Port = destination.Port
destination = newDestination
case 3:
destination.Port = h.overrideDestination.Port
}
if h.overrideOption == 0 {
h.logger.InfoContext(ctx, "outbound packet connection")
} else {
h.logger.InfoContext(ctx, "outbound packet connection to ", destination)
}
conn, err := h.dialer.ListenPacket(ctx, destination)
if err != nil {
return nil, err
}
conn = h.loopBack.NewPacketConn(bufio.NewPacketConn(conn), destination)
if originDestination != destination {
conn = bufio.NewNATPacketConn(bufio.NewPacketConn(conn), destination, originDestination)
}
return conn, nil
}
func (h *Direct) NewConnection(ctx context.Context, conn net.Conn, metadata adapter.InboundContext) error {
if h.loopBack.CheckConn(metadata.Source.AddrPort(), M.AddrPortFromNet(conn.LocalAddr())) {
return E.New("reject loopback connection to ", metadata.Destination)
}
return NewConnection(ctx, h, conn, metadata)
}
func (h *Direct) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata adapter.InboundContext) error {
if h.loopBack.CheckPacketConn(metadata.Source.AddrPort(), M.AddrPortFromNet(conn.LocalAddr())) {
return E.New("reject loopback packet connection to ", metadata.Destination)
}
return NewPacketConnection(ctx, h, conn, metadata)
}