[feat] Support .hec firmware format from Aeotec devices

[larstobi]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
When I try to update Aeotec Smart Switch 6 ZW096 with firmware downloaded from Aeotec n .hec format, I get the error message:

Error while calling api beginFirmwareUpdate: Unable to extract firmware from file: could not detect firmware format

Describe the solution you'd like
Correctly detecting the format and converting it to a usable format, and begin FW upgrade process.

Describe alternatives you've considered
None.

Additional context
EU firmware downloaded from link at the bottom of this page:
https://aeotec.freshdesk.com/support/solutions/articles/6000205150-update-smart-switch-6-firmware-via-homeseer-

[robertsLando]

@AlCalzone This is for you :) Also I suggest to move the guessFirmwareFormat function in zwave-js

[AlCalzone]

*.hec files are firmware files that were encrypted with the Homeseer encryption utility. Both the utility and the code to decrypt that is closed source. I've seen threads where it has been speculated that they use a simple encryption with a fixed key, but no hard evidence.
So in short: nothing we can do until someone reverse-engineers the encryption.

You can however ask the Aeotec support for their updater utility (which we can extract the firmware from).

[robertsLando]

You can however ask the Aeotec support for their updater utility (which we can extract the firmware from).

Or ask them to give us the docs to do it 😄

[AlCalzone]

Except Homeseer !== Aeotec. As far as I understand, they provide manufacturers with an encryption utility so they can upload encrypted firmware. Only the Homeseer software can decrypt these files.
From my experience, they'll give you the updater exe when you ask for it. In my case I wanted to update my WallMote but didn't find the files to do that.

[roflmao]

The exe is bundled here: https://aeotec.freshdesk.com/support/solutions/articles/6000134294-smart-switch-6-firmware-update-3-26-2018-

[robertsLando]

I think that we can close this so?

[larstobi]

@AlCalzone I asked Aeotec for the unencrypted firmware files, but they don't wish to give access to those files, because that will expose the source code, they say, and it's confidention to Aeotec.

I'm not sure how firmware upgrade is implemented on the devices, but I would think there at least should exist a public key in the devices that can verify a signature on the firmware code in order to verify it's publisher. In that case, exposing the code would not really be a problem, unless they are worried about competition looking at the disassembled machine code and picking up trade secrets. Which I guess is what they are most worried about.

From looking inside the .exe file in the source of for instance the Smart Switch 6 firmware updater tool, I found a string saying "ZW096_Smart_Switch_6_EU_V1_04_hex__TargetZwave__". Maybe that means we should be able to extract the firmware?

[AlCalzone]

If you have an updater exe, you can probably just plop it into the zwave-js update method. It will try and extract the firmware for you.

[robertsLando]

@AlCalzone What if he just rename the .hec to .exe?

[larstobi]

@robertsLando Probably not, since it's encrypted, or at least obfuscated.

@AlCalzone so, you mean the format guesser will search through and look for the start of the Intel Hex file? I decompiled the .exe and found lots of references to Intel hex.

[AlCalzone]

Yes, the format guesser will check if the exe file has two markers we expect and extractFirmware will then look for the firmware where it usually is in the file.
@robertsLando That won't work as the exe file needs to have a specific structure.

[larstobi]

@robertsLando @AlCalzone
I tried to update the Aeotec Smart Dimmer 6 right now and just dropped the SmartDimmer_6_EU_C_V1_07.exe file directly to the "Begin firmware upgrade" function. It Just Worked. Wow. :-D

[larstobi]

However, ZW096_Smart_Switch_6_EU_V1_04.exe does not work. I get "Error while calling api beginFirmwareUpdate: Unable to extract firmware from file: could not detect firmware format"

[AlCalzone]

Could you send me that file please?

[larstobi]

https://aeotec.freshdesk.com/helpdesk/attachments/6107410725

[larstobi]

@AlCalzone you can easily get it from the above link, but if there are problems, I can send it to you on Slack. :-)

[larstobi]

Link for other countries as well, in the bottom of this page https://aeotec.freshdesk.com/support/solutions/articles/6000235856-how-to-update-smart-switch-6-z-wave-firmware-

[AlCalzone]

@larstobi the failing exe files should be handled by zwave-js/node-zwave-js#1194. Since that branch depends on the GBL one, I'll either have to merge them without waiting for your test or just wait for confirmation.

[AlCalzone]

I've merged the branches, so the current zwave-js master should work.

[psarossy]

I'm trying to use this method do update my MultiSensor 6 US units, but nothing happens after I select the .exe file, the picker window disappears, and there's nothing in the log with that node, even with DEBUG level logging enabled..,
Any ideas?

@AlCalzone the encryption has been reverse engineered, but not sure if it's ok to post it here...

[AlCalzone]

@psarossy you can contact me via the email in my profile if you have some info to share.