-
Notifications
You must be signed in to change notification settings - Fork 0
/
convert_lorawan.go
136 lines (117 loc) · 4 KB
/
convert_lorawan.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
// Copyright © 2017 The Things Network
// Use of this source code is governed by the MIT license that can be found in the LICENSE file.
package handler
import (
pb_broker "github.com/TheThingsNetwork/ttn/api/broker"
"github.com/TheThingsNetwork/ttn/api/trace"
"github.com/TheThingsNetwork/ttn/core/handler/device"
"github.com/TheThingsNetwork/ttn/core/types"
"github.com/TheThingsNetwork/ttn/utils/errors"
"github.com/TheThingsNetwork/ttn/utils/pointer"
"github.com/apex/log"
"github.com/brocaar/lorawan"
)
func (h *handler) ConvertFromLoRaWAN(ctx log.Interface, ttnUp *pb_broker.DeduplicatedUplinkMessage, appUp *types.UplinkMessage, dev *device.Device) error {
// Check for LoRaWAN
if lorawan := ttnUp.ProtocolMetadata.GetLorawan(); lorawan == nil {
return errors.NewErrInvalidArgument("Uplink", "does not contain LoRaWAN metadata")
}
appUp.HardwareSerial = dev.DevEUI.String()
// 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
ttnUp.Trace = ttnUp.Trace.WithEvent(trace.CheckMICEvent)
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
}
func (h *handler) ConvertToLoRaWAN(ctx log.Interface, appDown *types.DownlinkMessage, ttnDown *pb_broker.DownlinkMessage, dev *device.Device) error {
// LoRaWAN: Unmarshal Downlink
var phyPayload lorawan.PHYPayload
err := phyPayload.UnmarshalBinary(ttnDown.Payload)
if err != nil {
return err
}
macPayload, ok := phyPayload.MACPayload.(*lorawan.MACPayload)
if !ok {
return errors.NewErrInvalidArgument("Downlink", "does not contain a MAC payload")
}
if ttnDown.DownlinkOption != nil && ttnDown.DownlinkOption.ProtocolConfig.GetLorawan() != nil {
macPayload.FHDR.FCnt = ttnDown.DownlinkOption.ProtocolConfig.GetLorawan().FCnt
}
// Abort when downlink not needed
if len(appDown.PayloadRaw) == 0 && !macPayload.FHDR.FCtrl.ACK && len(macPayload.FHDR.FOpts) == 0 {
return ErrNotNeeded
}
// Set FPort
if appDown.FPort != 0 {
macPayload.FPort = &appDown.FPort
}
// Set Payload
if len(appDown.PayloadRaw) > 0 {
ttnDown.Trace = ttnDown.Trace.WithEvent("set payload")
macPayload.FRMPayload = []lorawan.Payload{&lorawan.DataPayload{Bytes: appDown.PayloadRaw}}
if macPayload.FPort == nil || *macPayload.FPort == 0 {
macPayload.FPort = pointer.Uint8(1)
}
} else {
ttnDown.Trace = ttnDown.Trace.WithEvent("set empty payload")
macPayload.FRMPayload = []lorawan.Payload{}
}
// Encrypt
err = phyPayload.EncryptFRMPayload(lorawan.AES128Key(dev.AppSKey))
if err != nil {
return err
}
// Set MIC
err = phyPayload.SetMIC(lorawan.AES128Key(dev.NwkSKey))
if err != nil {
return err
}
// Marshal
phyPayloadBytes, err := phyPayload.MarshalBinary()
if err != nil {
return err
}
ttnDown.Payload = phyPayloadBytes
return nil
}