Generating DFU package for Bootloader image

RE: Generating DFU package for Bootloader image

beemavishnu — Tue, 19 May 2020 08:38:04 GMT

Thank you for your inputs.

Yes you are correct. I was trying different options by not giving key, boot-loader version, sd-req etc...

Might be I would have generated without key. Yes I say the warning you mentioned.

Thanks & Regards

Vishnu Beema

RE: Generating DFU package for Bootloader image

Einar Thorsrud — Tue, 19 May 2020 06:40:58 GMT

Hi Vishnu,

[quote user="beemavishnu"]1) Yes, I used same command to generate bootloader package. You mentioned unsigned. Is this based on "signature_type: UNSIGNED" in snapshot ?[/quote]

Yes, that is what I mean. You will get this if you don't specify a key, by omitting the --key-file option. In this case, the DFU package can only be used with bootloaders that don't require signed updates. If you do, nrfutil also prints the following warning:

|===============================================================|
|##      ##    ###    ########  ##    ## #### ##    ##  ######  |
|##  ##  ##   ## ##   ##     ## ###   ##  ##  ###   ## ##    ## |
|##  ##  ##  ##   ##  ##     ## ####  ##  ##  ####  ## ##       |
|##  ##  ## ##     ## ########  ## ## ##  ##  ## ## ## ##   ####|
|##  ##  ## ######### ##   ##   ##  ####  ##  ##  #### ##    ## |
|##  ##  ## ##     ## ##    ##  ##   ###  ##  ##   ### ##    ## |
| ###  ###  ##     ## ##     ## ##    ## #### ##    ##  ######  |
|===============================================================|
|You are not providing a signature key, which means the DFU     |
|files will not be signed, and are vulnerable to tampering.     |
|This is only compatible with a signature-less bootloader and is|
|not suitable for production environments.                      |
|===============================================================|

I am not aware of any other way to generate DFU packages without a signature.

[quote user="beemavishnu"]2) Below is the verion of nrfutil[/quote]

nrfutil version 5.2 should be OK. I have not found any references to issues with signing packages like this in that or other versions.

[quote user="beemavishnu"]3) I deleted existing package and regenerated. After that its shown as "signature_type: ECDSA_P256_SHA256" and able to do DFU of bootloader. But I am not sure why it was creating issue with previous package.[/quote]

It is good that it works now. Could it be that you just forgot the --key-file option when you generated the package initially, and now you remembered it?

Br,

Einar

RE: Generating DFU package for Bootloader image

beemavishnu — Mon, 18 May 2020 15:00:10 GMT

Hi,

Please find further details.

1) Yes, I used same command to generate bootloader package. You mentioned unsigned. Is this based on "signature_type: UNSIGNED" in snapshot ?

2) Below is the verion of nrfutil

3) I deleted existing package and regenerated. After that its shown as "signature_type: ECDSA_P256_SHA256" and able to do DFU of bootloader. But I am not sure why it was creating issue with previous package.

Thanks & Regards

Vishnu Beema

RE: Generating DFU package for Bootloader image

Einar Thorsrud — Mon, 18 May 2020 13:18:08 GMT

Hi Vishnu,

[quote user="beemavishnu"]1) Please find snapshot "nrfutil pkg display"[/quote]

This shows a package withoug signature. Did you get this using the following command (from your initial question)?

nrfutil pkg generate --hw-version 52 --bootloader-version 3 --bootloader secure_bootloader_uart_mbr_pca10056.hex --sd-req 0xCA --key-file private.key Secure_Bootloader_V3_package.zip

The command looks OK, and when I copy-paste it and test I get a correctly signed DFU image. Can you double-check? If this command really did produce an unsigned image it would be interesting to know the exact nrfutil version you are using ("nrfutil version").

[quote user="beemavishnu"]2) Yes, I am trying on nRF Development kit. To disable mass storage do you mean "Disabling the Mass Storage Device functionality". Will cause any problem after disabling. Is there a way to enable Mass storage in future.[/quote]

It is clear that there is an issue with your DFU package, so this is likely not related to the issue you are seeing. However, to answer your question you can re-enable the mass storage functionality using "MSDEnable".

Br,

Einar

RE: Generating DFU package for Bootloader image

beemavishnu — Fri, 15 May 2020 21:33:22 GMT

Hi,

1) Please find snapshot "nrfutil pkg display"

2) Yes, I am trying on nRF Development kit. To disable mass storage do you mean "Disabling the Mass Storage Device functionality". Will cause any problem after disabling. Is there a way to enable Mass storage in future.

Thanks & Regards

Vishnu Beema

RE: Generating DFU package for Bootloader image

Einar Thorsrud — Fri, 15 May 2020 15:37:10 GMT

Hi Vishnu,

1. It looks good to me. Can you check the DFU image with "nrfutil pkg display <zip>"? What does it say? If that does not provide any hints, then I wonder if you are testing on a DK or custom HW? If you are testing on a DK, then it could be good to disable the mass storage device feature of the onboard debugger as that could cause UART data corruption.

2. Yes, the version number should be increasing.

Einar