Golang PHYPayload.ValidateMIC方法代码示例

func (b *broker) HandleUplink(uplink *pb.UplinkMessage) (err error) {
	ctx := b.Ctx.WithField("GatewayID", uplink.GatewayMetadata.GatewayId)
	start := time.Now()
	defer func() {
		if err != nil {
			ctx.WithError(err).Warn("Could not handle uplink")
		} else {
			ctx.WithField("Duration", time.Now().Sub(start)).Info("Handled uplink")
		}
	}()

	time := time.Now()

	b.status.uplink.Mark(1)

	// De-duplicate uplink messages
	duplicates := b.deduplicateUplink(uplink)
	if len(duplicates) == 0 {
		return nil
	}

	b.status.uplinkUnique.Mark(1)

	ctx = ctx.WithField("Duplicates", len(duplicates))

	base := duplicates[0]

	if base.ProtocolMetadata.GetLorawan() == nil {
		return errors.NewErrInvalidArgument("Uplink", "does not contain LoRaWAN metadata")
	}

	// LoRaWAN: Unmarshal
	var phyPayload lorawan.PHYPayload
	err = phyPayload.UnmarshalBinary(base.Payload)
	if err != nil {
		return err
	}
	macPayload, ok := phyPayload.MACPayload.(*lorawan.MACPayload)
	if !ok {
		return errors.NewErrInvalidArgument("Uplink", "does not contain a MAC payload")
	}

	// Request devices from NS
	devAddr := types.DevAddr(macPayload.FHDR.DevAddr)
	ctx = ctx.WithFields(log.Fields{
		"DevAddr": devAddr,
		"FCnt":    macPayload.FHDR.FCnt,
	})
	var getDevicesResp *networkserver.DevicesResponse
	getDevicesResp, err = b.ns.GetDevices(b.Component.GetContext(b.nsToken), &networkserver.DevicesRequest{
		DevAddr: &devAddr,
		FCnt:    macPayload.FHDR.FCnt,
	})
	if err != nil {
		return errors.Wrap(errors.FromGRPCError(err), "NetworkServer did not return devices")
	}
	b.status.deduplication.Update(int64(len(getDevicesResp.Results)))
	if len(getDevicesResp.Results) == 0 {
		return errors.NewErrNotFound(fmt.Sprintf("Device with DevAddr %s and FCnt <= %d", devAddr, macPayload.FHDR.FCnt))
	}
	ctx = ctx.WithField("DevAddrResults", len(getDevicesResp.Results))

	// Sort by FCntUp to optimize the number of MIC checks
	sort.Sort(ByFCntUp(getDevicesResp.Results))

	// Find AppEUI/DevEUI through MIC check
	var device *pb_lorawan.Device
	var micChecks int
	var originalFCnt uint32
	for _, candidate := range getDevicesResp.Results {
		nwkSKey := lorawan.AES128Key(*candidate.NwkSKey)

		// First check with the 16 bit counter
		micChecks++
		ok, err = phyPayload.ValidateMIC(nwkSKey)
		if err != nil {
			return err
		}
		if ok {
			device = candidate
			break
		}

		originalFCnt = macPayload.FHDR.FCnt
		if candidate.Uses32BitFCnt {
			macPayload.FHDR.FCnt = fcnt.GetFull(candidate.FCntUp, uint16(originalFCnt))

			// If 32 bit counter has different value, perform another MIC check
			if macPayload.FHDR.FCnt != originalFCnt {
				micChecks++
				ok, err = phyPayload.ValidateMIC(nwkSKey)
				if err != nil {
					return err
				}
				if ok {
					device = candidate
					break
				}
			}
		}
//.........这里部分代码省略.........

func (h *handler) ConvertFromLoRaWAN(ctx log.Interface, ttnUp *pb_broker.DeduplicatedUplinkMessage, appUp *types.UplinkMessage) error {
	// Find Device
	dev, err := h.devices.Get(ttnUp.AppId, ttnUp.DevId)
	if err != nil {
		return err
	}

	// Check for LoRaWAN
	if lorawan := ttnUp.ProtocolMetadata.GetLorawan(); lorawan == nil {
		return errors.NewErrInvalidArgument("Activation", "does not contain LoRaWAN metadata")
	}

	// LoRaWAN: Unmarshal Uplink
	var phyPayload lorawan.PHYPayload
	err = phyPayload.UnmarshalBinary(ttnUp.Payload)
	if err != nil {
		return err
	}
	macPayload, ok := phyPayload.MACPayload.(*lorawan.MACPayload)
	if !ok {
		return errors.NewErrInvalidArgument("Uplink", "does not contain a MAC payload")
	}
	macPayload.FHDR.FCnt = ttnUp.ProtocolMetadata.GetLorawan().FCnt
	appUp.FCnt = macPayload.FHDR.FCnt

	ctx = ctx.WithField("FCnt", appUp.FCnt)

	// LoRaWAN: Validate MIC
	ok, err = phyPayload.ValidateMIC(lorawan.AES128Key(dev.NwkSKey))
	if err != nil {
		return err
	}
	if !ok {
		return errors.NewErrNotFound("device that validates MIC")
	}

	// LoRaWAN: Decrypt
	if macPayload.FPort != nil && *macPayload.FPort != 0 && len(macPayload.FRMPayload) == 1 {
		appUp.FPort = *macPayload.FPort
		ctx = ctx.WithField("FCnt", appUp.FPort)
		if err := phyPayload.DecryptFRMPayload(lorawan.AES128Key(dev.AppSKey)); err != nil {
			return errors.NewErrInternal("Could not decrypt payload")
		}
		if len(macPayload.FRMPayload) == 1 {
			payload, ok := macPayload.FRMPayload[0].(*lorawan.DataPayload)
			if !ok {
				return errors.NewErrInvalidArgument("Uplink FRMPayload", "must be of type *lorawan.DataPayload")
			}
			appUp.PayloadRaw = payload.Bytes
		}
	}

	// LoRaWAN: Publish ACKs as events
	if macPayload.FHDR.FCtrl.ACK {
		h.mqttEvent <- &types.DeviceEvent{
			AppID: appUp.AppID,
			DevID: appUp.DevID,
			Event: types.DownlinkAckEvent,
		}
	}

	return nil
}