/
addons.go
161 lines (141 loc) · 4 KB
/
addons.go
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//go:build !confonly
// +build !confonly
package encoding
import (
"io"
"google.golang.org/protobuf/proto"
"github.com/bmclab-git/v2ray-core/v5/common/buf"
"github.com/bmclab-git/v2ray-core/v5/common/errors"
"github.com/bmclab-git/v2ray-core/v5/common/protocol"
)
// EncodeHeaderAddons Add addons byte to the header
func EncodeHeaderAddons(buffer *buf.Buffer, addons *Addons) error {
if err := buffer.WriteByte(0); err != nil {
return newError("failed to write addons protobuf length").Base(err)
}
return nil
}
func DecodeHeaderAddons(buffer *buf.Buffer, reader io.Reader) (*Addons, error) {
addons := new(Addons)
buffer.Clear()
if _, err := buffer.ReadFullFrom(reader, 1); err != nil {
return nil, newError("failed to read addons protobuf length").Base(err)
}
if length := int32(buffer.Byte(0)); length != 0 {
buffer.Clear()
if _, err := buffer.ReadFullFrom(reader, length); err != nil {
return nil, newError("failed to read addons protobuf value").Base(err)
}
if err := proto.Unmarshal(buffer.Bytes(), addons); err != nil {
return nil, newError("failed to unmarshal addons protobuf value").Base(err)
}
}
return addons, nil
}
// EncodeBodyAddons returns a Writer that auto-encrypt content written by caller.
func EncodeBodyAddons(writer io.Writer, request *protocol.RequestHeader, addons *Addons) buf.Writer {
if request.Command == protocol.RequestCommandUDP {
return NewMultiLengthPacketWriter(writer.(buf.Writer))
}
return buf.NewWriter(writer)
}
// DecodeBodyAddons returns a Reader from which caller can fetch decrypted body.
func DecodeBodyAddons(reader io.Reader, request *protocol.RequestHeader, addons *Addons) buf.Reader {
if request.Command == protocol.RequestCommandUDP {
return NewLengthPacketReader(reader)
}
return buf.NewReader(reader)
}
func NewMultiLengthPacketWriter(writer buf.Writer) *MultiLengthPacketWriter {
return &MultiLengthPacketWriter{
Writer: writer,
}
}
type MultiLengthPacketWriter struct {
buf.Writer
}
func (w *MultiLengthPacketWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
defer buf.ReleaseMulti(mb)
if len(mb)+1 > 64*1024*1024 {
return errors.New("value too large")
}
sliceSize := len(mb) + 1
mb2Write := make(buf.MultiBuffer, 0, sliceSize)
for _, b := range mb {
length := b.Len()
if length == 0 || length+2 > buf.Size {
continue
}
eb := buf.New()
if err := eb.WriteByte(byte(length >> 8)); err != nil {
eb.Release()
continue
}
if err := eb.WriteByte(byte(length)); err != nil {
eb.Release()
continue
}
if _, err := eb.Write(b.Bytes()); err != nil {
eb.Release()
continue
}
mb2Write = append(mb2Write, eb)
}
if mb2Write.IsEmpty() {
return nil
}
return w.Writer.WriteMultiBuffer(mb2Write)
}
type LengthPacketWriter struct {
io.Writer
cache []byte
}
func (w *LengthPacketWriter) WriteMultiBuffer(mb buf.MultiBuffer) error {
length := mb.Len() // none of mb is nil
if length == 0 {
return nil
}
defer func() {
w.cache = w.cache[:0]
}()
w.cache = append(w.cache, byte(length>>8), byte(length))
for i, b := range mb {
w.cache = append(w.cache, b.Bytes()...)
b.Release()
mb[i] = nil
}
if _, err := w.Write(w.cache); err != nil {
return newError("failed to write a packet").Base(err)
}
return nil
}
func NewLengthPacketReader(reader io.Reader) *LengthPacketReader {
return &LengthPacketReader{
Reader: reader,
cache: make([]byte, 2),
}
}
type LengthPacketReader struct {
io.Reader
cache []byte
}
func (r *LengthPacketReader) ReadMultiBuffer() (buf.MultiBuffer, error) {
if _, err := io.ReadFull(r.Reader, r.cache); err != nil { // maybe EOF
return nil, newError("failed to read packet length").Base(err)
}
length := int32(r.cache[0])<<8 | int32(r.cache[1])
mb := make(buf.MultiBuffer, 0, length/buf.Size+1)
for length > 0 {
size := length
if size > buf.Size {
size = buf.Size
}
length -= size
b := buf.New()
if _, err := b.ReadFullFrom(r.Reader, size); err != nil {
return nil, newError("failed to read packet payload").Base(err)
}
mb = append(mb, b)
}
return mb, nil
}