Xray-core/proxy/vmess/outbound/outbound.go

250 lines
7.5 KiB
Go

package outbound
import (
"context"
"crypto/hmac"
"crypto/sha256"
"hash/crc64"
"time"
"github.com/xtls/xray-core/common"
"github.com/xtls/xray-core/common/buf"
"github.com/xtls/xray-core/common/errors"
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/common/platform"
"github.com/xtls/xray-core/common/protocol"
"github.com/xtls/xray-core/common/retry"
"github.com/xtls/xray-core/common/session"
"github.com/xtls/xray-core/common/signal"
"github.com/xtls/xray-core/common/task"
"github.com/xtls/xray-core/common/xudp"
core "github.com/xtls/xray-core/core"
"github.com/xtls/xray-core/features/policy"
"github.com/xtls/xray-core/proxy/vmess"
"github.com/xtls/xray-core/proxy/vmess/encoding"
"github.com/xtls/xray-core/transport"
"github.com/xtls/xray-core/transport/internet"
"github.com/xtls/xray-core/transport/internet/stat"
)
// Handler is an outbound connection handler for VMess protocol.
type Handler struct {
serverList *protocol.ServerList
serverPicker protocol.ServerPicker
policyManager policy.Manager
cone bool
}
// New creates a new VMess outbound handler.
func New(ctx context.Context, config *Config) (*Handler, error) {
serverList := protocol.NewServerList()
for _, rec := range config.Receiver {
s, err := protocol.NewServerSpecFromPB(rec)
if err != nil {
return nil, errors.New("failed to parse server spec").Base(err)
}
serverList.AddServer(s)
}
v := core.MustFromContext(ctx)
handler := &Handler{
serverList: serverList,
serverPicker: protocol.NewRoundRobinServerPicker(serverList),
policyManager: v.GetFeature(policy.ManagerType()).(policy.Manager),
cone: ctx.Value("cone").(bool),
}
return handler, nil
}
// Process implements proxy.Outbound.Process().
func (h *Handler) Process(ctx context.Context, link *transport.Link, dialer internet.Dialer) error {
outbounds := session.OutboundsFromContext(ctx)
ob := outbounds[len(outbounds)-1]
if !ob.Target.IsValid() {
return errors.New("target not specified").AtError()
}
ob.Name = "vmess"
ob.CanSpliceCopy = 3
var rec *protocol.ServerSpec
var conn stat.Connection
err := retry.ExponentialBackoff(5, 200).On(func() error {
rec = h.serverPicker.PickServer()
rawConn, err := dialer.Dial(ctx, rec.Destination())
if err != nil {
return err
}
conn = rawConn
return nil
})
if err != nil {
return errors.New("failed to find an available destination").Base(err).AtWarning()
}
defer conn.Close()
target := ob.Target
errors.LogInfo(ctx, "tunneling request to ", target, " via ", rec.Destination().NetAddr())
command := protocol.RequestCommandTCP
if target.Network == net.Network_UDP {
command = protocol.RequestCommandUDP
}
if target.Address.Family().IsDomain() && target.Address.Domain() == "v1.mux.cool" {
command = protocol.RequestCommandMux
}
user := rec.PickUser()
request := &protocol.RequestHeader{
Version: encoding.Version,
User: user,
Command: command,
Address: target.Address,
Port: target.Port,
Option: protocol.RequestOptionChunkStream,
}
account := request.User.Account.(*vmess.MemoryAccount)
request.Security = account.Security
if request.Security == protocol.SecurityType_AES128_GCM || request.Security == protocol.SecurityType_NONE || request.Security == protocol.SecurityType_CHACHA20_POLY1305 {
request.Option.Set(protocol.RequestOptionChunkMasking)
}
if shouldEnablePadding(request.Security) && request.Option.Has(protocol.RequestOptionChunkMasking) {
request.Option.Set(protocol.RequestOptionGlobalPadding)
}
if request.Security == protocol.SecurityType_ZERO {
request.Security = protocol.SecurityType_NONE
request.Option.Clear(protocol.RequestOptionChunkStream)
request.Option.Clear(protocol.RequestOptionChunkMasking)
}
if account.AuthenticatedLengthExperiment {
request.Option.Set(protocol.RequestOptionAuthenticatedLength)
}
input := link.Reader
output := link.Writer
hashkdf := hmac.New(sha256.New, []byte("VMessBF"))
hashkdf.Write(account.ID.Bytes())
behaviorSeed := crc64.Checksum(hashkdf.Sum(nil), crc64.MakeTable(crc64.ISO))
var newCtx context.Context
var newCancel context.CancelFunc
if session.TimeoutOnlyFromContext(ctx) {
newCtx, newCancel = context.WithCancel(context.Background())
}
session := encoding.NewClientSession(ctx, int64(behaviorSeed))
sessionPolicy := h.policyManager.ForLevel(request.User.Level)
ctx, cancel := context.WithCancel(ctx)
timer := signal.CancelAfterInactivity(ctx, func() {
cancel()
if newCancel != nil {
newCancel()
}
}, sessionPolicy.Timeouts.ConnectionIdle)
if request.Command == protocol.RequestCommandUDP && h.cone && request.Port != 53 && request.Port != 443 {
request.Command = protocol.RequestCommandMux
request.Address = net.DomainAddress("v1.mux.cool")
request.Port = net.Port(666)
}
requestDone := func() error {
defer timer.SetTimeout(sessionPolicy.Timeouts.DownlinkOnly)
writer := buf.NewBufferedWriter(buf.NewWriter(conn))
if err := session.EncodeRequestHeader(request, writer); err != nil {
return errors.New("failed to encode request").Base(err).AtWarning()
}
bodyWriter, err := session.EncodeRequestBody(request, writer)
if err != nil {
return errors.New("failed to start encoding").Base(err)
}
bodyWriter2 := bodyWriter
if request.Command == protocol.RequestCommandMux && request.Port == 666 {
bodyWriter = xudp.NewPacketWriter(bodyWriter, target, xudp.GetGlobalID(ctx))
}
if err := buf.CopyOnceTimeout(input, bodyWriter, time.Millisecond*100); err != nil && err != buf.ErrNotTimeoutReader && err != buf.ErrReadTimeout {
return errors.New("failed to write first payload").Base(err)
}
if err := writer.SetBuffered(false); err != nil {
return err
}
if err := buf.Copy(input, bodyWriter, buf.UpdateActivity(timer)); err != nil {
return err
}
if request.Option.Has(protocol.RequestOptionChunkStream) && !account.NoTerminationSignal {
if err := bodyWriter2.WriteMultiBuffer(buf.MultiBuffer{}); err != nil {
return err
}
}
return nil
}
responseDone := func() error {
defer timer.SetTimeout(sessionPolicy.Timeouts.UplinkOnly)
reader := &buf.BufferedReader{Reader: buf.NewReader(conn)}
header, err := session.DecodeResponseHeader(reader)
if err != nil {
return errors.New("failed to read header").Base(err)
}
h.handleCommand(rec.Destination(), header.Command)
bodyReader, err := session.DecodeResponseBody(request, reader)
if err != nil {
return errors.New("failed to start encoding response").Base(err)
}
if request.Command == protocol.RequestCommandMux && request.Port == 666 {
bodyReader = xudp.NewPacketReader(&buf.BufferedReader{Reader: bodyReader})
}
return buf.Copy(bodyReader, output, buf.UpdateActivity(timer))
}
if newCtx != nil {
ctx = newCtx
}
responseDonePost := task.OnSuccess(responseDone, task.Close(output))
if err := task.Run(ctx, requestDone, responseDonePost); err != nil {
return errors.New("connection ends").Base(err)
}
return nil
}
var (
enablePadding = false
)
func shouldEnablePadding(s protocol.SecurityType) bool {
return enablePadding || s == protocol.SecurityType_AES128_GCM || s == protocol.SecurityType_CHACHA20_POLY1305 || s == protocol.SecurityType_AUTO
}
func init() {
common.Must(common.RegisterConfig((*Config)(nil), func(ctx context.Context, config interface{}) (interface{}, error) {
return New(ctx, config.(*Config))
}))
const defaultFlagValue = "NOT_DEFINED_AT_ALL"
paddingValue := platform.NewEnvFlag(platform.UseVmessPadding).GetValue(func() string { return defaultFlagValue })
if paddingValue != defaultFlagValue {
enablePadding = true
}
}