// Create creates the given node-session. The DevAddr must contain the same NwkID as the configured NetID. Node-sessions will expire automatically after the configured TTL.
func (a *NodeSessionAPI) Create(ctx context.Context, req *pb.CreateNodeSessionRequest) (*pb.CreateNodeSessionResponse, error) {
var appEUI, devEUI lorawan.EUI64
var appSKey, nwkSKey lorawan.AES128Key
var devAddr lorawan.DevAddr
if err := appEUI.UnmarshalText([]byte(req.AppEUI)); err != nil {
return nil, err
}
if err := devEUI.UnmarshalText([]byte(req.DevEUI)); err != nil {
return nil, err
}
if err := appSKey.UnmarshalText([]byte(req.AppSKey)); err != nil {
return nil, err
}
if err := nwkSKey.UnmarshalText([]byte(req.NwkSKey)); err != nil {
return nil, err
}
if err := devAddr.UnmarshalText([]byte(req.DevAddr)); err != nil {
return nil, err
}
var cFList *lorawan.CFList
if len(req.CFList) > len(cFList) {
return nil, fmt.Errorf("max CFList channels is %d", len(cFList))
}
if len(req.CFList) > 0 {
cFList = &lorawan.CFList{}
for i, f := range req.CFList {
cFList[i] = f
}
}
ns := models.NodeSession{
DevAddr: devAddr,
AppEUI: appEUI,
DevEUI: devEUI,
AppSKey: appSKey,
NwkSKey: nwkSKey,
FCntUp: req.FCntUp,
FCntDown: req.FCntDown,
RXDelay: uint8(req.RxDelay),
RX1DROffset: uint8(req.Rx1DROffset),
CFList: cFList,
}
if err := a.validateNodeSession(ns); err != nil {
return nil, err
}
if err := storage.CreateNodeSession(a.ctx.RedisPool, ns); err != nil {
return nil, err
}
return &pb.CreateNodeSessionResponse{}, nil
}
// Delete deletes the node-session matching the given DevAddr.
func (a *NodeSessionAPI) Delete(ctx context.Context, req *pb.DeleteNodeSessionRequest) (*pb.DeleteNodeSessionResponse, error) {
var devAddr lorawan.DevAddr
if err := devAddr.UnmarshalText([]byte(req.DevAddr)); err != nil {
return nil, err
}
if err := storage.DeleteNodeSession(a.ctx.RedisPool, devAddr); err != nil {
return nil, err
}
return &pb.DeleteNodeSessionResponse{}, nil
}
// Get returns the node-session matching the given DevAddr.
func (a *NodeSessionAPI) Get(ctx context.Context, req *pb.GetNodeSessionRequest) (*pb.GetNodeSessionResponse, error) {
var devAddr lorawan.DevAddr
if err := devAddr.UnmarshalText([]byte(req.DevAddr)); err != nil {
return nil, err
}
ns, err := storage.GetNodeSession(a.ctx.RedisPool, devAddr)
if err != nil {
return nil, err
}
return a.nodeSessionToResponse(ns)
}
// getRandomDevAddr returns a random free DevAddr. Note that the 7 MSB will be
// set to the NwkID (based on the configured NetID).
// TODO: handle collission with retry?
func getRandomDevAddr(p *redis.Pool, netID lorawan.NetID) (lorawan.DevAddr, error) {
var d lorawan.DevAddr
b := make([]byte, len(d))
if _, err := rand.Read(b); err != nil {
return d, fmt.Errorf("could not read from random reader: %s", err)
}
copy(d[:], b)
d[0] = d[0] & 1 // zero out 7 msb
d[0] = d[0] ^ (netID.NwkID() << 1) // set 7 msb to NwkID
c := p.Get()
defer c.Close()
key := "node_session_" + d.String()
val, err := redis.Int(c.Do("EXISTS", key))
if err != nil {
return lorawan.DevAddr{}, fmt.Errorf("test DevAddr %s exist error: %s", d, err)
}
if val == 1 {
return lorawan.DevAddr{}, fmt.Errorf("DevAddr %s already exists", d)
}
return d, nil
}