DFU from up-to-date iOS

RE: DFU from up-to-date iOS

Vidar Berg — Thu, 25 Feb 2021 15:13:20 GMT

Hi Marie,

No worries. Unfortunately, it's not as trivial to switch to variant 1 through a DFU. It will require some changes to the bootloader as discussed in this thread: https://devzone.nordicsemi.com/f/nordic-q-a/46927/update-app-bootloader-without-bonds-to-with-bond-by-dfu-in-single-shoot

Best regards,

Vidar

RE: DFU from up-to-date iOS

MarieMaurer — Thu, 25 Feb 2021 12:20:04 GMT

Hi Vidar,

sorry for the late answer and thanks for you previous answer, it was helpful and solved our problem. But I think I need a follow-up on the last answer:
We have used variant 2 for the last weeks. Now a colleague tried variant 1 and got it also successfully working. We decided to go with variant 1 if possible.

We now tried to update from variant 2 to variant 1, but it looks like it is missing the bond information needed by the bootloader. Do you know if perhaps a partial update (only app) followed by a complete update could solve this? Or not possible at all and only way is to update complete flash via JTAG (which is a bit more complicated, because some customers are already testing with it and some users work from home office due to Covid-19)?

Many thanks!

Best regards,

Marie

RE: DFU from up-to-date iOS

Vidar Berg — Thu, 26 Nov 2020 10:34:35 GMT

Hi Marie,

Yes, in that case, you may consider enabling these flags in the bootloader and application. This will enable Buttonless Secure DFU Service with bonds.

Another way you can prevent un-bonded clients from initiating DFU is by increasing the security level on the buttonless characteristic in ble_dfu_unbonded.c:ble_dfu_buttonless_char_add() from SEC_OPEN.

Best regards,

Vidar

RE: DFU from up-to-date iOS

MarieMaurer — Thu, 26 Nov 2020 10:17:57 GMT

Hi Vendor,

good to hear! Thanks!

But when we want to allow updates only by a bonded device, is it then the right way to use this/these defines?
If yes, where to set them? Only in the bootloader, the app, both?

Best regards,

Marie

RE: DFU from up-to-date iOS

Vidar Berg — Thu, 26 Nov 2020 10:13:55 GMT

Hi Marie,

Then you should not be impacted by this issue. It's safe to do buttonless DFU with NRF_DFU_BLE_BUTTONLESS_SUPPORTS_BONDS disabled (ie Buttonless Secure DFU Service without bonds).

Best regards,

Vidar

RE: DFU from up-to-date iOS

MarieMaurer — Thu, 26 Nov 2020 09:37:22 GMT

Hi Vidar,

thanks for your answer!

I am using the one which is in

nRF5_SDK_17.0.2_d674dde\examples\dfu\secure_bootloader

Best regards,

Marie

RE: DFU from up-to-date iOS

Vidar Berg — Thu, 26 Nov 2020 08:34:48 GMT

Hello Marie,

Are you sure you're using the legacy bootloader? The configuration options you listed are for the Secure bootloader which was introduced in nRF5 SDK v12.0.0.

Best regards,

Vidar