mihomo/transport/trojan/trojan.go
2023-11-02 11:11:35 +08:00

340 lines
7.2 KiB
Go

package trojan
import (
"context"
"crypto/sha256"
"crypto/tls"
"encoding/binary"
"encoding/hex"
"errors"
"io"
"net"
"net/http"
"sync"
N "github.com/Dreamacro/clash/common/net"
"github.com/Dreamacro/clash/common/pool"
"github.com/Dreamacro/clash/component/ca"
tlsC "github.com/Dreamacro/clash/component/tls"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/clash/transport/socks5"
"github.com/Dreamacro/clash/transport/vmess"
)
const (
// max packet length
maxLength = 8192
)
var (
defaultALPN = []string{"h2", "http/1.1"}
defaultWebsocketALPN = []string{"http/1.1"}
crlf = []byte{'\r', '\n'}
)
type Command = byte
const (
CommandTCP byte = 1
CommandUDP byte = 3
// deprecated XTLS commands, as souvenirs
commandXRD byte = 0xf0 // XTLS direct mode
commandXRO byte = 0xf1 // XTLS origin mode
)
type Option struct {
Password string
ALPN []string
ServerName string
SkipCertVerify bool
Fingerprint string
ClientFingerprint string
Reality *tlsC.RealityConfig
}
type WebsocketOption struct {
Host string
Port string
Path string
Headers http.Header
V2rayHttpUpgrade bool
}
type Trojan struct {
option *Option
hexPassword []byte
}
func (t *Trojan) StreamConn(ctx context.Context, conn net.Conn) (net.Conn, error) {
alpn := defaultALPN
if len(t.option.ALPN) != 0 {
alpn = t.option.ALPN
}
tlsConfig := &tls.Config{
NextProtos: alpn,
MinVersion: tls.VersionTLS12,
InsecureSkipVerify: t.option.SkipCertVerify,
ServerName: t.option.ServerName,
}
var err error
tlsConfig, err = ca.GetSpecifiedFingerprintTLSConfig(tlsConfig, t.option.Fingerprint)
if err != nil {
return nil, err
}
if len(t.option.ClientFingerprint) != 0 {
if t.option.Reality == nil {
utlsConn, valid := vmess.GetUTLSConn(conn, t.option.ClientFingerprint, tlsConfig)
if valid {
ctx, cancel := context.WithTimeout(context.Background(), C.DefaultTLSTimeout)
defer cancel()
err := utlsConn.(*tlsC.UConn).HandshakeContext(ctx)
return utlsConn, err
}
} else {
ctx, cancel := context.WithTimeout(context.Background(), C.DefaultTLSTimeout)
defer cancel()
return tlsC.GetRealityConn(ctx, conn, t.option.ClientFingerprint, tlsConfig, t.option.Reality)
}
}
if t.option.Reality != nil {
return nil, errors.New("REALITY is based on uTLS, please set a client-fingerprint")
}
tlsConn := tls.Client(conn, tlsConfig)
// fix tls handshake not timeout
ctx, cancel := context.WithTimeout(context.Background(), C.DefaultTLSTimeout)
defer cancel()
err = tlsConn.HandshakeContext(ctx)
return tlsConn, err
}
func (t *Trojan) StreamWebsocketConn(ctx context.Context, conn net.Conn, wsOptions *WebsocketOption) (net.Conn, error) {
alpn := defaultWebsocketALPN
if len(t.option.ALPN) != 0 {
alpn = t.option.ALPN
}
tlsConfig := &tls.Config{
NextProtos: alpn,
MinVersion: tls.VersionTLS12,
InsecureSkipVerify: t.option.SkipCertVerify,
ServerName: t.option.ServerName,
}
return vmess.StreamWebsocketConn(ctx, conn, &vmess.WebsocketConfig{
Host: wsOptions.Host,
Port: wsOptions.Port,
Path: wsOptions.Path,
Headers: wsOptions.Headers,
V2rayHttpUpgrade: wsOptions.V2rayHttpUpgrade,
TLS: true,
TLSConfig: tlsConfig,
ClientFingerprint: t.option.ClientFingerprint,
})
}
func (t *Trojan) WriteHeader(w io.Writer, command Command, socks5Addr []byte) error {
buf := pool.GetBuffer()
defer pool.PutBuffer(buf)
buf.Write(t.hexPassword)
buf.Write(crlf)
buf.WriteByte(command)
buf.Write(socks5Addr)
buf.Write(crlf)
_, err := w.Write(buf.Bytes())
return err
}
func (t *Trojan) PacketConn(conn net.Conn) net.PacketConn {
return &PacketConn{
Conn: conn,
}
}
func writePacket(w io.Writer, socks5Addr, payload []byte) (int, error) {
buf := pool.GetBuffer()
defer pool.PutBuffer(buf)
buf.Write(socks5Addr)
binary.Write(buf, binary.BigEndian, uint16(len(payload)))
buf.Write(crlf)
buf.Write(payload)
return w.Write(buf.Bytes())
}
func WritePacket(w io.Writer, socks5Addr, payload []byte) (int, error) {
if len(payload) <= maxLength {
return writePacket(w, socks5Addr, payload)
}
offset := 0
total := len(payload)
for {
cursor := offset + maxLength
if cursor > total {
cursor = total
}
n, err := writePacket(w, socks5Addr, payload[offset:cursor])
if err != nil {
return offset + n, err
}
offset = cursor
if offset == total {
break
}
}
return total, nil
}
func ReadPacket(r io.Reader, payload []byte) (net.Addr, int, int, error) {
addr, err := socks5.ReadAddr(r, payload)
if err != nil {
return nil, 0, 0, errors.New("read addr error")
}
uAddr := addr.UDPAddr()
if uAddr == nil {
return nil, 0, 0, errors.New("parse addr error")
}
if _, err = io.ReadFull(r, payload[:2]); err != nil {
return nil, 0, 0, errors.New("read length error")
}
total := int(binary.BigEndian.Uint16(payload[:2]))
if total > maxLength {
return nil, 0, 0, errors.New("packet invalid")
}
// read crlf
if _, err = io.ReadFull(r, payload[:2]); err != nil {
return nil, 0, 0, errors.New("read crlf error")
}
length := len(payload)
if total < length {
length = total
}
if _, err = io.ReadFull(r, payload[:length]); err != nil {
return nil, 0, 0, errors.New("read packet error")
}
return uAddr, length, total - length, nil
}
func New(option *Option) *Trojan {
return &Trojan{option, hexSha224([]byte(option.Password))}
}
var _ N.EnhancePacketConn = (*PacketConn)(nil)
type PacketConn struct {
net.Conn
remain int
rAddr net.Addr
mux sync.Mutex
}
func (pc *PacketConn) WriteTo(b []byte, addr net.Addr) (int, error) {
return WritePacket(pc, socks5.ParseAddr(addr.String()), b)
}
func (pc *PacketConn) ReadFrom(b []byte) (int, net.Addr, error) {
pc.mux.Lock()
defer pc.mux.Unlock()
if pc.remain != 0 {
length := len(b)
if pc.remain < length {
length = pc.remain
}
n, err := pc.Conn.Read(b[:length])
if err != nil {
return 0, nil, err
}
pc.remain -= n
addr := pc.rAddr
if pc.remain == 0 {
pc.rAddr = nil
}
return n, addr, nil
}
addr, n, remain, err := ReadPacket(pc.Conn, b)
if err != nil {
return 0, nil, err
}
if remain != 0 {
pc.remain = remain
pc.rAddr = addr
}
return n, addr, nil
}
func (pc *PacketConn) WaitReadFrom() (data []byte, put func(), addr net.Addr, err error) {
pc.mux.Lock()
defer pc.mux.Unlock()
destination, err := socks5.ReadAddr0(pc.Conn)
if err != nil {
return nil, nil, nil, err
}
addr = destination.UDPAddr()
data = pool.Get(pool.UDPBufferSize)
put = func() {
_ = pool.Put(data)
}
_, err = io.ReadFull(pc.Conn, data[:2+2]) // u16be length + CR LF
if err != nil {
if put != nil {
put()
}
return nil, nil, nil, err
}
length := binary.BigEndian.Uint16(data)
if length > 0 {
data = data[:length]
_, err = io.ReadFull(pc.Conn, data)
if err != nil {
if put != nil {
put()
}
return nil, nil, nil, err
}
} else {
if put != nil {
put()
}
return nil, nil, addr, nil
}
return
}
func hexSha224(data []byte) []byte {
buf := make([]byte, 56)
hash := sha256.Sum224(data)
hex.Encode(buf, hash[:])
return buf
}