fix: fix commons stream

commons/stream.go

@@ -2,85 +2,39 @@ package commons
 
 import (
 	"bytes"
-	"errors"
 	"io"
 )
 
-type CommonStream interface {
-	io.ReadSeeker
-	ReadN(n int) (bs []byte, err error)
-	PeekN(n int) (bs []byte, err error)
-	EOF() bool
-	CurrentIndex() int64
-}
-
 type Stream struct {
 	io.ReadSeeker
-	current int64
-	err     error
-}
-
-func (s *Stream) Read(b []byte) (n int, err error) {
-	if _, err = s.Seek(s.current, io.SeekStart); err != nil {
-		s.err = err
-		return
-	}
-	n, err = s.ReadSeeker.Read(b)
-	if err != nil {
-		s.err = err
-		return
-	}
-	s.current += int64(n)
-	return
 }
 
 func (s *Stream) ReadN(n int) (bs []byte, err error) {
-	oldCurrent := s.current
 	bs = make([]byte, n)
 	_, err = io.ReadFull(s, bs)
-	if err != nil {
-		s.current = oldCurrent
-		bs = nil
-	}
 	return
 }
 
-func (s *Stream) PeekN(n int) (bs []byte, err error) {
-	oldOffset := s.current
-	bs, err = s.ReadN(n)
-	s.current = oldOffset
-	return
-}
-
-func (s *Stream) EOF() bool {
-	return s.err != nil
-}
-
 func (s *Stream) CurrentIndex() int64 {
-	return s.current
+	n, _ := s.Seek(0, io.SeekCurrent)
+	return n
 }
 
-func (s *Stream) Seek(offset int64, whence int) (int64, error) {
-	var abs int64
-	switch whence {
-	case io.SeekStart:
-		abs = offset
-	case io.SeekCurrent:
-		abs = s.current + offset
-	default:
-		return 0, errors.New("bytes.Reader.Seek: invalid whence")
+func (s *Stream) PeekN(n int) (bs []byte, err error) {
+	bs, err = s.ReadN(n)
+	if err != nil {
+		return
 	}
-	if abs < 0 {
-		return 0, errors.New("bytes.Reader.Seek: negative position")
+	_, err = s.Seek(int64(-n), io.SeekCurrent)
+	if err != nil {
+		return
 	}
-	s.current = abs
-	return s.ReadSeeker.Seek(abs, whence)
+	return
 }
 
 func NewStreamFromReadSeeker(rs io.ReadSeeker) *Stream {
 	return &Stream{
 		ReadSeeker: rs,
-		current:    0,
 	}
 }
 

commons/stream_test.go

@@ -1,9 +1,10 @@
 package commons
 
 import (
-	"github.com/stretchr/testify/require"
 	"io"
 	"testing"
+
+	"github.com/stretchr/testify/require"
 )
 
 func TestStream_Read(t *testing.T) {
@@ -35,12 +36,8 @@ func TestStream_ReadN(t *testing.T) {
 	bs, err = s.ReadN(5)
 	require.Nil(t, err)
 	require.Equal(t, []byte("11111"), bs)
-	bs, err = s.ReadN(23)
+	_, err = s.ReadN(23)
 	require.Equal(t, io.ErrUnexpectedEOF, err)
-	require.Nil(t, bs)
-	bs, err = s.ReadN(10)
-	require.Nil(t, err)
-	require.Equal(t, []byte("2222233333"), bs)
 }
 
 func TestStream_PeekN(t *testing.T) {
@@ -50,20 +47,21 @@ func TestStream_PeekN(t *testing.T) {
 	bs, err = s.PeekN(5)
 	require.Nil(t, err)
 	require.Equal(t, []byte("11111"), bs)
-	bs, err = s.PeekN(25)
+	_, err = s.PeekN(25)
 	require.Nil(t, err)
-	require.Equal(t, []byte("1111122222333334444455555"), bs)
-	bs, err = s.PeekN(30)
-	require.Equal(t, io.ErrUnexpectedEOF, err)
-	require.Nil(t, bs)
-	_, _ = s.ReadN(10)
+}
+
+func TestStream_CurrentIndex(t *testing.T) {
+	var bs []byte
+	var err error
+	s := NewStream([]byte("1111122222333334444455555"))
 	bs, err = s.PeekN(5)
 	require.Nil(t, err)
-	require.Equal(t, []byte("33333"), bs)
-	bs, err = s.PeekN(10)
+	require.Equal(t, []byte("11111"), bs)
+	require.Equal(t, int64(0), s.CurrentIndex())
+
+	bs, err = s.ReadN(5)
 	require.Nil(t, err)
-	require.Equal(t, []byte("3333344444"), bs)
-	bs, err = s.PeekN(20)
-	require.Equal(t, io.ErrUnexpectedEOF, err)
-	require.Nil(t, bs)
+	require.Equal(t, []byte("11111"), bs)
+	require.Equal(t, int64(5), s.CurrentIndex())
 }

serz/buffer.go

@@ -1,29 +1,30 @@
 package serz
 
 import (
-	"github.com/phith0n/zkar/commons"
 	"io"
+
+	"github.com/phith0n/zkar/commons"
 )
 
 type ObjectStream struct {
-	commons.CommonStream
+	*commons.Stream
 	handler    uint32
 	references map[uint32]Object
 }
 
 func NewObjectStream(bs []byte) *ObjectStream {
 	return &ObjectStream{
-		CommonStream: commons.NewStream(bs),
-		handler:      JAVA_BASE_WRITE_HANDLE,
-		references:   make(map[uint32]Object),
+		Stream:     commons.NewStream(bs),
+		handler:    JAVA_BASE_WRITE_HANDLE,
+		references: make(map[uint32]Object),
 	}
 }
 
 func NewObjectStreamFromReadSeeker(r io.ReadSeeker) *ObjectStream {
 	return &ObjectStream{
-		CommonStream: commons.NewStreamFromReadSeeker(r),
-		handler:      JAVA_BASE_WRITE_HANDLE,
-		references:   make(map[uint32]Object),
+		Stream:     commons.NewStreamFromReadSeeker(r),
+		handler:    JAVA_BASE_WRITE_HANDLE,
+		references: make(map[uint32]Object),
 	}
 }
 

serz/parser.go

@@ -3,9 +3,10 @@ package serz
 import (
 	"bytes"
 	"fmt"
-	"github.com/phith0n/zkar/commons"
 	"io"
 	"os"
+
+	"github.com/phith0n/zkar/commons"
 )
 
 type Object interface {
@@ -66,16 +67,6 @@ func FromJDK8u20Bytes(data []byte) (*Serialization, error) {
 	return FromBytes(data)
 }
 
-func FromJDK8u20ReadSeeker(data []byte) (*Serialization, error) {
-	data = bytes.Replace(
-		data,
-		[]byte{0x00, 0x7e, 0x00, 0x09},
-		[]byte{0x00, 0x7e, 0x00, 0x09, JAVA_TC_ENDBLOCKDATA},
-		1,
-	)
-	return FromReadSeeker(bytes.NewReader(data))
-}
-
 func (ois *Serialization) ToString() string {
 	var b = commons.NewPrinter()
 	b.Printf("@Magic - %s", commons.Hexify(ois.MagicNumber))

serz/parser_test.go

@@ -3,13 +3,14 @@ package serz
 import (
 	"bytes"
 	"fmt"
-	"github.com/stretchr/testify/require"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 	"testing"
 	"time"
+
+	"github.com/stretchr/testify/require"
 )
 
 const existsFlag = "✅"
@@ -27,19 +28,6 @@ func extractPackage(name string) string {
 	return name
 }
 
-func TestJDK8u20FromReadSeeker(t *testing.T) {
-	var filename = "../testcases/pwntester/JDK8u20.ser"
-	data, err := ioutil.ReadFile(filename)
-	require.Nil(t, err)
-
-	ser, err := FromJDK8u20ReadSeeker(data)
-	require.Nilf(t, err, "an error is occurred in file %v", filename)
-	serFromBytes, err := FromJDK8u20Bytes(data)
-	require.Equal(t, ser, serFromBytes)
-	require.Nilf(t, err, "an error is occurred in file %v", filename)
-	require.Truef(t, bytes.Equal(data, ser.ToJDK8u20Bytes()), "original data is different from generation data in file %v", filename)
-}
-
 func TestYsoserial(t *testing.T) {
 	walkAndTest("../testcases/ysoserial/*.ser", t, func(filename string, data []byte, ser *Serialization) {
 		require.Truef(