Add Snell protocol. Refactor MASQUE HTTP/2, Fair Queue. Update XHTTP, OpenVPN, Sudoku, Fallback. Fixes

transport/openvpn/lzo.go

@@ -0,0 +1,48 @@
+package openvpn
+
+import (
+	"bytes"
+	"errors"
+
+	"github.com/rasky/go-lzo"
+)
+
+const (
+	lzoCompressNone = 0xFA
+	lzoCompressLZO  = 0x66
+)
+
+var ErrLZODecompress = errors.New("lzo decompression failed")
+
+func lzo1xDecompressSafe(src []byte) ([]byte, error) {
+	if len(src) == 0 {
+		return nil, ErrLZODecompress
+	}
+
+	switch src[0] {
+	case lzoCompressNone:
+		if len(src) > 1 {
+			return src[1:], nil
+		}
+		return nil, nil
+	case lzoCompressLZO:
+		if len(src) > 1 {
+			r := bytes.NewReader(src[1:])
+			out, err := lzo.Decompress1X(r, len(src)-1, 0)
+			if err != nil {
+				return nil, ErrLZODecompress
+			}
+			return out, nil
+		}
+		return nil, nil
+	default:
+		return nil, ErrLZODecompress
+	}
+}
+
+func lzo1xCompressSafe(src []byte) ([]byte, error) {
+	lzoPacket := make([]byte, 1+len(src))
+	lzoPacket[0] = lzoCompressNone
+	copy(lzoPacket[1:], src)
+	return lzoPacket, nil
+}