ws: fixed a bug in frame reader

This commit is contained in:
nadoo 2018-07-23 01:41:18 +08:00
parent cdabe41e34
commit 68d8fb8b60

View File

@ -30,13 +30,16 @@ import (
)
const (
finalBit byte = 1 << 7
defaultFrameSize = 4096
maxFrameHeaderSize = 2 + 8 + 4 // Fixed header + length + mask
maskBit byte = 1 << 7
opCodeBinary byte = 2
opClose byte = 8
maskKeyLen = 4
defaultFrameSize = 4096
maxFrameHeaderSize = 2 + 8 + 4 // Fixed header + length + mask
maskKeyLen = 4
)
const (
finalBit byte = 1 << 7
maskBit byte = 1 << 7
opCodeBinary byte = 2
opClose byte = 8
)
type frameWriter struct {
@ -85,18 +88,21 @@ func (w *frameWriter) ReadFrom(r io.Reader) (n int64, err error) {
binary.BigEndian.PutUint64(buf[2:2+lengthFieldLen], uint64(nr))
}
// header and length
_, ew := w.Writer.Write(buf[:2+lengthFieldLen])
if ew != nil {
err = ew
break
}
// maskkey
_, ew = w.Writer.Write(w.maskKey)
if ew != nil {
err = ew
break
}
// payload
payloadBuf = payloadBuf[:nr]
for i := range payloadBuf {
payloadBuf[i] = payloadBuf[i] ^ w.maskKey[i%4]
@ -123,8 +129,8 @@ func (w *frameWriter) ReadFrom(r io.Reader) (n int64, err error) {
type frameReader struct {
io.Reader
buf []byte
leftover []byte
buf []byte
leftBytes int64
}
// FrameReader returns a chunked reader
@ -136,41 +142,49 @@ func FrameReader(r io.Reader) io.Reader {
}
func (r *frameReader) Read(b []byte) (int, error) {
if len(r.leftover) > 0 {
n := copy(b, r.leftover)
r.leftover = r.leftover[n:]
return n, nil
if r.leftBytes == 0 {
// get msg header
_, err := io.ReadFull(r.Reader, r.buf[:2])
if err != nil {
return 0, err
}
// final := r.buf[0]&finalBit != 0
// frameType := int(r.buf[0] & 0xf)
// mask := r.buf[1]&maskBit != 0
r.leftBytes = int64(r.buf[1] & 0x7f)
switch r.leftBytes {
case 126:
io.ReadFull(r.Reader, r.buf[:2])
r.leftBytes = int64(binary.BigEndian.Uint16(r.buf[0:]))
case 127:
io.ReadFull(r.Reader, r.buf[:8])
r.leftBytes = int64(binary.BigEndian.Uint64(r.buf[0:]))
}
}
var n, m int
var err error
if r.leftBytes > int64(len(r.buf)) {
if len(b) < len(r.buf) {
n, err = r.Reader.Read(r.buf[:len(b)])
} else {
n, err = r.Reader.Read(r.buf)
}
} else {
if int64(len(b)) < r.leftBytes {
n, err = io.ReadFull(r.Reader, r.buf[:len(b)])
} else {
n, err = io.ReadFull(r.Reader, r.buf[:r.leftBytes])
}
}
// get msg header
_, err := io.ReadFull(r.Reader, r.buf[:2])
if err != nil {
return 0, err
}
// final := r.buf[0]&finalBit != 0
// frameType := int(r.buf[0] & 0xf)
// mask := r.buf[1]&maskBit != 0
len := int64(r.buf[1] & 0x7f)
switch len {
case 126:
io.ReadFull(r.Reader, r.buf[:2])
len = int64(binary.BigEndian.Uint16(r.buf[0:]))
case 127:
io.ReadFull(r.Reader, r.buf[:8])
len = int64(binary.BigEndian.Uint64(r.buf[0:]))
}
// get payload
_, err = io.ReadFull(r.Reader, r.buf[:len])
if err != nil {
return 0, err
}
m := copy(b, r.buf[:len])
if m < int(len) {
r.leftover = r.buf[m:len]
}
m = copy(b, r.buf[:n])
r.leftBytes -= int64(m)
return m, err
}