Xray-core/proxy/vmess/encoding/commands.go

74 lines
1.7 KiB
Go

package encoding
import (
"encoding/binary"
"io"
"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/protocol"
)
var (
ErrCommandTooLarge = errors.New("Command too large.")
ErrCommandTypeMismatch = errors.New("Command type mismatch.")
ErrInvalidAuth = errors.New("Invalid auth.")
ErrInsufficientLength = errors.New("Insufficient length.")
ErrUnknownCommand = errors.New("Unknown command.")
)
func MarshalCommand(command interface{}, writer io.Writer) error {
if command == nil {
return ErrUnknownCommand
}
var cmdID byte
var factory CommandFactory
switch command.(type) {
default:
return ErrUnknownCommand
}
buffer := buf.New()
defer buffer.Release()
err := factory.Marshal(command, buffer)
if err != nil {
return err
}
auth := Authenticate(buffer.Bytes())
length := buffer.Len() + 4
if length > 255 {
return ErrCommandTooLarge
}
common.Must2(writer.Write([]byte{cmdID, byte(length), byte(auth >> 24), byte(auth >> 16), byte(auth >> 8), byte(auth)}))
common.Must2(writer.Write(buffer.Bytes()))
return nil
}
func UnmarshalCommand(cmdID byte, data []byte) (protocol.ResponseCommand, error) {
if len(data) <= 4 {
return nil, ErrInsufficientLength
}
expectedAuth := Authenticate(data[4:])
actualAuth := binary.BigEndian.Uint32(data[:4])
if expectedAuth != actualAuth {
return nil, ErrInvalidAuth
}
var factory CommandFactory
switch cmdID {
default:
return nil, ErrUnknownCommand
}
return factory.Unmarshal(data[4:])
}
type CommandFactory interface {
Marshal(command interface{}, writer io.Writer) error
Unmarshal(data []byte) (interface{}, error)
}