Golang Conn.GetIv方法代码示例

// copyOta copies data from src to dst with ota verification.
//
// This function is copied from shadowsocks library with some modification.
func (s *ShadowServer) copyOta(dst net.Conn, src *ss.Conn) (int64, error) {
	// sometimes it have to fill large block
	buf := make([]byte, LargeBufferSize)
	for {
		src.SetReadDeadline(time.Now().Add(ReadTimeout))
		if n, err := io.ReadFull(src, buf[:dataLenLen+hmacSha1Len]); err != nil {
			return int64(n), err
		}
		src.SetReadDeadline(time.Time{})

		dataLen := binary.BigEndian.Uint16(buf[:dataLenLen])
		expectedHmacSha1 := buf[dataLenLen:idxData0]

		var dataBuf []byte
		if len(buf) < int(idxData0+dataLen) {
			dataBuf = make([]byte, dataLen)
		} else {
			dataBuf = buf[idxData0 : idxData0+dataLen]
		}
		if n, err := io.ReadFull(src, dataBuf); err != nil {
			return int64(n), err
		}
		chunkIdBytes := make([]byte, 4)
		chunkId := src.GetAndIncrChunkId()
		binary.BigEndian.PutUint32(chunkIdBytes, chunkId)
		actualHmacSha1 := ss.HmacSha1(append(src.GetIv(), chunkIdBytes...), dataBuf)
		if !bytes.Equal(expectedHmacSha1, actualHmacSha1) {
			return 0, errors.New("ota error: mismatch")
		}

		if n, err := dst.Write(dataBuf); err != nil {
			return int64(n), err
		}
	}
}

func getRequest(conn *ss.Conn, auth bool) (host string, ota bool, err error) {
	ss.SetReadTimeout(conn)

	// buf size should at least have the same size with the largest possible
	// request size (when addrType is 3, domain name has at most 256 bytes)
	// 1(addrType) + 1(lenByte) + 256(max length address) + 2(port) + 10(hmac-sha1)
	buf := make([]byte, 270)
	// read till we get possible domain length field
	if _, err = io.ReadFull(conn, buf[:idType+1]); err != nil {
		return
	}

	var reqStart, reqEnd int
	addrType := buf[idType]
	switch addrType & ss.AddrMask {
	case typeIPv4:
		reqStart, reqEnd = idIP0, idIP0+lenIPv4
	case typeIPv6:
		reqStart, reqEnd = idIP0, idIP0+lenIPv6
	case typeDm:
		if _, err = io.ReadFull(conn, buf[idType+1:idDmLen+1]); err != nil {
			return
		}
		reqStart, reqEnd = idDm0, int(idDm0+buf[idDmLen]+lenDmBase)
	default:
		err = fmt.Errorf("addr type %d not supported", addrType&ss.AddrMask)
		return
	}

	if _, err = io.ReadFull(conn, buf[reqStart:reqEnd]); err != nil {
		return
	}

	// Return string for typeIP is not most efficient, but browsers (Chrome,
	// Safari, Firefox) all seems using typeDm exclusively. So this is not a
	// big problem.
	switch addrType & ss.AddrMask {
	case typeIPv4:
		host = net.IP(buf[idIP0 : idIP0+net.IPv4len]).String()
	case typeIPv6:
		host = net.IP(buf[idIP0 : idIP0+net.IPv6len]).String()
	case typeDm:
		host = string(buf[idDm0 : idDm0+buf[idDmLen]])
	}
	// parse port
	port := binary.BigEndian.Uint16(buf[reqEnd-2 : reqEnd])
	host = net.JoinHostPort(host, strconv.Itoa(int(port)))
	// if specified one time auth enabled, we should verify this
	if auth || addrType&ss.OneTimeAuthMask > 0 {
		ota = true
		if _, err = io.ReadFull(conn, buf[reqEnd:reqEnd+lenHmacSha1]); err != nil {
			return
		}
		iv := conn.GetIv()
		key := conn.GetKey()
		actualHmacSha1Buf := ss.HmacSha1(append(iv, key...), buf[:reqEnd])
		if !bytes.Equal(buf[reqEnd:reqEnd+lenHmacSha1], actualHmacSha1Buf) {
			err = fmt.Errorf("verify one time auth failed, iv=%v key=%v data=%v", iv, key, buf[:reqEnd])
			return
		}
	}
	return
}

func PipeThenCloseOta(src *ss.Conn, dst net.Conn, is_res bool, host string, user user.User) {
	const (
		dataLenLen  = 2
		hmacSha1Len = 10
		idxData0    = dataLenLen + hmacSha1Len
	)

	defer func() {
		dst.Close()
	}()
	var pipeBuf = leakybuf.NewLeakyBuf(nBuf, bufSize)
	buf := pipeBuf.Get()
	// sometimes it have to fill large block
	for i := 1; ; i += 1 {
		SetReadTimeout(src)
		n, err := io.ReadFull(src, buf[:dataLenLen+hmacSha1Len])
		if err != nil {
			if err == io.EOF {
				break
			}
			Log.Debug(fmt.Sprintf("conn=%p #%v read header error n=%v: %v", src, i, n, err))
			break
		}
		dataLen := binary.BigEndian.Uint16(buf[:dataLenLen])
		expectedHmacSha1 := buf[dataLenLen:idxData0]

		var dataBuf []byte
		if len(buf) < int(idxData0+dataLen) {
			dataBuf = make([]byte, dataLen)
		} else {
			dataBuf = buf[idxData0 : idxData0+dataLen]
		}
		if n, err := io.ReadFull(src, dataBuf); err != nil {
			if err == io.EOF {
				break
			}
			Log.Debug(fmt.Sprintf("conn=%p #%v read data error n=%v: %v", src, i, n, err))
			break
		}
		chunkIdBytes := make([]byte, 4)
		chunkId := src.GetAndIncrChunkId()
		binary.BigEndian.PutUint32(chunkIdBytes, chunkId)
		actualHmacSha1 := ss.HmacSha1(append(src.GetIv(), chunkIdBytes...), dataBuf)
		if !bytes.Equal(expectedHmacSha1, actualHmacSha1) {
			Log.Debug(fmt.Sprintf("conn=%p #%v read data hmac-sha1 mismatch, iv=%v chunkId=%v src=%v dst=%v len=%v expeced=%v actual=%v", src, i, src.GetIv(), chunkId, src.RemoteAddr(), dst.RemoteAddr(), dataLen, expectedHmacSha1, actualHmacSha1))
			break
		}

		if n, err := dst.Write(dataBuf); err != nil {
			Log.Debug(fmt.Sprintf("conn=%p #%v write data error n=%v: %v", dst, i, n, err))
			break
		}
		if is_res {
			err := storage.IncrSize(user, n)
			if err != nil {
				Log.Error(err)
			}
			Log.Debug(fmt.Sprintf("[port-%d] store size: %d", user.GetPort(), n))
		}
	}
	return
}