func NewChunkWriter(w io.Writer, c btncrypt.Cipher, h ChunkHeader) (io.WriteCloser, error) {
if err := h.WriteTo(w, c); err != nil {
return nil, fmt.Errorf("Failed to write header: %v", err)
}
return btncrypt.NewWriteCloser(w, c, int(h.PayloadLen))
}
func TestBtnEncryptWriter_PartialWrite(t *testing.T) {
payload := util.RandomBytes(1024 * 1024)
var b bytes.Buffer
bew, err := btncrypt.NewWriteCloser(&b, tu.TestCipher(), len(payload))
if err != nil {
t.Errorf("Failed to create BtnEncryptWriter: %v", err)
}
verifyWrite(t, bew, payload[:3])
verifyWrite(t, bew, payload[3:1024])
verifyWrite(t, bew, payload[1024:4096])
verifyWrite(t, bew, payload[4096:])
if err := bew.Close(); err != nil {
t.Errorf("bew.Close failed: %v", err)
}
plain, err := btncrypt.Decrypt(tu.TestCipher(), b.Bytes(), len(payload))
if err != nil {
t.Errorf("Failed to decrypt: %v", err)
}
if !bytes.Equal(payload, plain) {
t.Errorf("Failed to restore original payload")
}
}
func (h ChunkHeader) WriteTo(w io.Writer, c btncrypt.Cipher) error {
h.FrameEncapsulation = CurrentFrameEncapsulation
if h.PayloadLen > MaxChunkPayloadLen {
return fmt.Errorf("payload length too big: %d", h.PayloadLen)
}
if len(h.OrigFilename) > MaxOrigFilenameLen {
h.OrigFilename = filepath.Base(h.OrigFilename)
if len(h.OrigFilename) > MaxOrigFilenameLen {
h.OrigFilename = "<filename_too_long>"
}
}
if _, err := w.Write([]byte{ChunkSignatureMagic1, ChunkSignatureMagic2}); err != nil {
return fmt.Errorf("Failed to write signature magic: %v", err)
}
if _, err := w.Write([]byte{CurrentFormat}); err != nil {
return fmt.Errorf("Failed to write format byte: %v", err)
}
var b bytes.Buffer
enc := gob.NewEncoder(&b)
if err := enc.Encode(h); err != nil {
return err
}
framelen := ChunkHeaderLength - c.FrameOverhead() - SignatureLength - 1
paddinglen := framelen - b.Len()
if paddinglen < 0 {
log.Fatalf("SHOULD NOT BE REACHED: Marshaled ChunkHeader size too large")
}
bew, err := btncrypt.NewWriteCloser(w, c, framelen)
if _, err := b.WriteTo(bew); err != nil {
return fmt.Errorf("Failed to initialize frame encryptor: %v", err)
}
if err != nil {
return fmt.Errorf("Header frame gob payload write failed: %v", err)
}
// zero padding
if _, err := bew.Write(make([]byte, paddinglen)); err != nil {
return fmt.Errorf("Header frame zero padding write failed: %v", err)
}
if err := bew.Close(); err != nil {
return fmt.Errorf("Header frame close failed: %v", err)
}
return nil
}
func (ch *ChunkIO) writeContentFrame(i int, f *decryptedContentFrame) error {
// the offset of the start of the frame in blob
blobOffset := ch.encryptedFrameOffset(i)
wr := &blobstore.OffsetWriter{ch.bh, int64(blobOffset)}
bew, err := btncrypt.NewWriteCloser(wr, ch.c, len(f.P))
if err != nil {
return fmt.Errorf("Failed to create BtnEncryptWriteCloser: %v", err)
}
defer func() {
if err := bew.Close(); err != nil {
log.Printf("Failed to Close BtnEncryptWriteCloser: %v", err)
}
}()
if _, err := bew.Write(f.P); err != nil {
return fmt.Errorf("Failed to encrypt frame: %v", err)
}
ch.header.PayloadVersion++
ch.needsHeaderUpdate = true
log.Printf("ChunkIO: Wrote content frame idx: %d", i)
return nil
}
func TestBtnEncryptWriter_WriteAtOnce(t *testing.T) {
//payload := RandomBytes(1024 * 1024)
payload := []byte("short string")
var b bytes.Buffer
bew, err := btncrypt.NewWriteCloser(&b, tu.TestCipher(), len(payload))
if err != nil {
t.Errorf("Failed to create BtnEncryptWriter: %v", err)
}
verifyWrite(t, bew, payload)
if err := bew.Close(); err != nil {
t.Errorf("bew.Close failed: %v", err)
}
plain, err := btncrypt.Decrypt(tu.TestCipher(), b.Bytes(), len(payload))
if err != nil {
t.Errorf("Failed to decrypt: %v", err)
}
if !bytes.Equal(payload, plain) {
t.Errorf("Failed to restore original payload")
}
}