💬 Building a Raspberry Pi Gateway

[gohan]

@alowhum said in 💬 Building a Raspberry Pi Gateway:

PiGPIO

what are you using that for?

[MasMat]

@alowhum I'm not using the GPIO for anything else.
I had everything working (mysgw-MQTT, Mosquitto, Node-Red and OH2) for almost 6h. Then I moved the set-up and everything went south: cant get mosquitto to start, cant get mysgw to connect to that or another Mosquitto broker, OH2 seems to ignore everything...
Spent the last 24h trying to resurrect Mosquitto but it's beyond me what's wrong.

I remember reading that mysgw renders rest of the gpio unusable. Maybe that's giving you problems.

[gohan]

I am running 2 gateway instances, one nrf24 and one rfm69 so I guess you can run other things

[alowhum]

@gohan: but you had to do a lot of black magic to get there right?

[gohan]

not at all, I just followed the guide in the forum

[alowhum]

@masmat I got the Pi Zero W working fine with other things using the GPIO.

• A fresh install helped
• It could be that I now use the PiGPIO library for the project.
• It could be the switch to another powersupply. I was using the official pi powersupply, but I suspect something was wrong with it. A cheap 3A chinese adapter is working fine.

Either way: it all works now.

I have a few n00bish questions about enabling encryption (without signing, so save space and ram):

• Is putting an AES key in MyConfig.h really all I have to do? Don't I also have to put that in all the sensor nodes? And is that proces complicated, using a signing sketch and whatnot?
• Can I have an 'opportunistic' network, where I have some encrypted nodes, and some unencrypted ones? If I could mix them this would make switching to encryption less stressful. I can't easily change two of my nodes.
• If I change the network, I'd like to move the NRF to channel 100 (juist outside of the normal WiFi frequencies). Do I also have to set that in all nodes, or is setting it in the gateway enough?

[Anticimex]

@alowhum encryption is all or nothing. You can't leave one node without encryption if your gateway encrypts the messages it send.
And you will need to personalize your nodes to get the AES key into them. The documentation on security describes that process.

[gohan]

@alowhum if you put it in myconfig.h also on the arduino library you can just recompile the nodes and you are good.

[Anticimex]

@gohan not anymore. Only for pre 2.2.0 releases.

[gohan]

It is still working on mine 😅

[Anticimex]

@gohan in other words, you use an old release ;)

[gohan]

I can assure you I am using 2.2 from development as I am also running new driver. So unless you changed something in the last 3 weeks on the development branch it still works, unless the nodes are keeping the key saved.

[Anticimex]

@gohan have you verified your communications are actually encrypted?

[Anticimex]

@gohan If you see here, you will find that unless you use the simple password option, AES key is fetched from EEPROM: https://github.com/mysensors/MySensors/blob/28c4f3f19e7026f56fd9bbc61d566f770fd7a9d2/hal/transport/MyTransportRF24.cpp#L68
So either you are using the simple flag, nothing at all, or not using the key you think you use.

[gohan]

I ll have to check, but I put the key in the gateway myconfig.h

[Anticimex]

@gohan Perhaps on a rpi GW where there is no EEPROM, but I am talking about the nodes.

[gohan]

Well, if I have communication working it means the node should be encrypting data. I'll have to try with clear eeprom and try flashing sketch again

[Anticimex]

@gohan not if there is no encryption at all. You could try to use simple password option on a node with various passwords and see if it is detected by your gw at all.

[gohan]

@anticimex I guess you were right... the gw and node aren't using the AES key. So where am I supposed to add it in the gateway?

[Anticimex]

@gohan you set that with the configure arguments I suspect, but I can't see it in the documentation. @marceloaqno perhaps knows how the rPi port handles this. I'm on a phone so I can't check the code easily. But you should be able to find it in the transport driver for rPi. On the rPi it can probably be defined in the code as it does not have a personalizer.