How to reject old firmware version from AWS FOTA at NRF9160 side?

Take a look at https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.8.0/nrf/ug_fw_update.html#preventing-downgrades-using-mcuboot to see how to prevent downgrades with MCUboot.

Best regards,

Simon

Hi Simon

1. I tried sdk connect v1.8.0 application update example. Added configuration settings to prevent downgrade.

   However, it popped error as the project was opened. Anything wrong?

2. The project customer referred to was v1.3.0. So, does it support mcuboot preventing downgrade?

Jeffery

Jeffery said:

 However, it popped error as the project was opened. Anything wrong?

If you look at this command

west build -b board application -- \
-DCONFIG_BOOTLOADER_MCUBOOT=y \
-DCONFIG_MCUBOOT_IMAGE_VERSION=\"0.1.2\+3\" \
-Dmcuboot_CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=y \
-Dmcuboot_CONFIG_BOOT_UPGRADE_ONLY=y

You can see that some of the configs are meant for the application (<application>/prj.conf), and some of the configs are meant for mcuboot (<ncs>/bootloader/mcuboot). Specifically the configs written like "-D<config>" are for the application, while the configs written like "-Dmcuboot<config>" are for mcuboot. The reason it doesn't work is because you have added everything to the application prj.conf file.

You can also take a look at the ticket mcuboot customer config to see how to set mcuboot configurations from the application.

Jeffery said:

2. The project customer referred to was v1.3.0. So, does it support mcuboot preventing downgrade?

Yes, downgrade preventions should be possible in NCS v1.3.0. I could not find any information about it in the NCS v1.3.0 documentation, but I found some lines mentioning it in the MCUBoot v1.3.0 documentation: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.3.0/mcuboot/design.html#downgrade-prevention

In the above link, both SW based and HW based downgrade preventions are described. I forgot to mention the HW based method in my initial answer.

Best regards,

Simon

Hi Simon

1. It can compile now. My test project is v1.8.0 application update. What I did as below.

A. Added below string at CMakeLists.txt

set(mcuboot_OVERLAY_CONFIG
${CMAKE_CURRENT_LIST_DIR}/mcuboot.conf
)

B. Create mcuboot.conf at project folder. Then, fill below settngs.

CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=y
CONFIG_BOOT_UPGRADE_ONLY=y

C. Added below setting at prj.conf

CONFIG_MCUBOOT_IMAGE_VERSION="0.1.0"

2. AWS address was default and not overwritten. So, nrf9160 will connect to Nordic's AWS account.

3. After press button1, it started downloading data. As reached to 100%, reset DK for swap test.

   The FOTA was done. 

   However, it shall not be successfully since mcuboot version at my DK (1.0.0) is newer than version

   from AWS(0.0.0). Why is it successful to be downgraded?

Jeffery

Hi Simon

1. It can compile now. My test project is v1.8.0 application update. What I did as below.

A. Added below string at CMakeLists.txt

set(mcuboot_OVERLAY_CONFIG
${CMAKE_CURRENT_LIST_DIR}/mcuboot.conf
)

B. Create mcuboot.conf at project folder. Then, fill below settngs.

CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=y
CONFIG_BOOT_UPGRADE_ONLY=y

C. Added below setting at prj.conf

CONFIG_MCUBOOT_IMAGE_VERSION="0.1.0"

2. AWS address was default and not overwritten. So, nrf9160 will connect to Nordic's AWS account.

3. After press button1, it started downloading data. As reached to 100%, reset DK for swap test.

   The FOTA was done. 

   However, it shall not be successfully since mcuboot version at my DK (1.0.0) is newer than version

   from AWS(0.0.0). Why is it successful to be downgraded?

Jeffery

Could you show me the files <sample>/build/zephyr/.config and <sample>/build/mcuboot/zephyr/.config of the firmware on the DK (where version is 1.0.0).

Can you also show me the file <sample>/build/zephyr/.config of the firmware to be updated (where version is 0.0.0).

Best regards,

Simon

Hi Simon

1.config =>v1.8.0...\app_test\build_nrf9160dk_nrf9160_ns\zephyr\.config

2.config=>v1.8.0...\app_test\build_nrf9160dk_nrf9160_ns\mcuboot\zephyr\.config

Also, I attached CMakeLists.txt and log result.

The log result was different to what I said at previous message after I put set(mcuboot_OVERLAY_CONFIG~ just under cmake_minimum_required at CMakeLists.txt.

As to the file <sample>/build/zephyr/.config of the firmware to be updated (where version is 0.0.0), I don't have it. I used your demo AWS FOTA to verify as below in prj.conf. 

CONFIG_DOWNLOAD_HOST="nrfconnectsdk.s3.eu-central-1.amazonaws.com"
CONFIG_DOWNLOAD_FILE="app_update.bin"
CONFIG_APPLICATION_VERSION=1

I tested this myself, and it seems like there is some bugs with the OVERLAY_CONFIG functionality. I will report internally as a bug*

Instead I added the MCUBoot configs in the CMakeListst.txt like this:

set(mcuboot_CONFIG_MCUBOOT_DOWNGRADE_PREVENTION
    y
)
set(mcuboot_CONFIG_BOOT_UPGRADE_ONLY
    y
)

Could you test the following sample with NCS v1.8.0:

• Build it using the board nrf9160dk_nrf9160_ns
• You should get the following output:

...
...
...
29 NRF_PDM              Non-Secure      OK
30 NRF_I2S              Non-Secure      OK
31 NRF_GPIOTE1          Non-Secure      OK

SPM: NS image at 0x20200
SPM: NS MSP at 0x200154d0
SPM: NS reset vector at 0x216cd
SPM: prepare to jump to Non-Secure image.
*** Booting Zephyr OS build v2.7.0-ncs1  ***
MCUBOOT IMAGE VERSION: 1.0.0
Hello World! nrf9160dk_nrf9160

• Next, change CONFIG_MCUBOOT_IMAGE_VERSION to "0.0.0" in mcuboot_prevent_downgrade/prj.conf
• Build the sample again (pristine) without flashing it
  • Make sure CONFIG_MCUBOOT_IMAGE_VERSION is "0.0.0" in <sample>/build/zephyr/.config
• Open the command line in ../mcuboot_prevent_downgrade/build/zephyr and run the following command:

nrfjprog --program app_moved_test_update.hex

Read more about the file app_moved_test_update.hex in the MCUBoot documentation

• Reset the nRF9160 DK and you should see the following output:

*** Booting Zephyr OS build v2.7.0-ncs1  ***
I: Starting bootloader
I: Swap type: test
E: insufficient version in secondary slot
I: Bootloader chainload address offset: 0x10000
*** Booting Zephyr OS build v2.7.0-ncs1  ***
Flash regions           Domain          Permissions
00 03 0x00000 0x20000   Secure          rwxl
...
...
...
SPM: prepare to jump to Non-Secure image.
*** Booting Zephyr OS build v2.7.0-ncs1  ***
MCUBOOT IMAGE VERSION: 1.0.0
Hello World! nrf9160dk_nrf9160

Report back to me if this works for you or not

Best regards,

Simon

*I had to enable these in mcuboot.conf, then "Unable to find bootable image.." went away

CONFIG_PARTITION_MANAGER_ENABLED=y
CONFIG_FLASH_MAP_CUSTOM=y

Then I added the below configs to mcuboot.conf as well, but they were not propogated to the file <sample>/build/mcuboot/zephyr/.config

CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=y
CONFIG_BOOT_UPGRADE_ONLY=y

I will report this internally and get back to you in this ticket when we find a solution

Hi Simon

1.

Added the MCUBoot configs in the CMakeListst.tx of sdk v1.8.0 application_update, preventing downgrade did work.

set(mcuboot_CONFIG_MCUBOOT_DOWNGRADE_PREVENTION
y
)
set(mcuboot_CONFIG_BOOT_UPGRADE_ONLY
y
)

2.

However, my project was based on sdk connect v1.3.0 http_application_update.

When I tried FOTA, it can download new app_update.bin from your AWS "nrfconnectsdk.s3.eu-central-

1.amazonaws.com". But, swap failed. Log show error and secondary image was invalid.

Jeffery

I just tested the sample mcuboot_prevent_downgrade I uploaded in my last reply with NCS v1.3.0, with the following addition in CMakeLists.txt

set(mcuboot_CONFIG_BOOT_SWAP_USING_MOVE n)

 I followed the same instructions as in my last reply and I got this output

** Booting Zephyr OS build v2.3.0-rc1-ncs1  ***
[00:00:00.003,540] <inf> mcuboot: Starting bootloader
[00:00:00.009,613] <inf> mcuboot: Swap type: test
[00:00:00.014,801] <err> mcuboot: insufficient version in secondary slot
[00:00:09.301,605] <inf> mcuboot: Bootloader chainload address offset: 0x10000
[00:00:09.309,387] <inf> mcuboot: Jumping to the first image slot
*** Booting Zephyr OS build v2.3.0-rc1-ncs1  ***
Flash regions           Domain          Permissions
00 02 0x00000 0x18000   Secure          rwxl
03 31 0x18000 0x100000  Non-Secure      rwxl

Non-secure callable region 0 placed in flash region 2 with size 32.

SRAM region             Domain          Permissions
00 07 0x00000 0x10000   Secure          rwxl
08 31 0x10000 0x40000   Non-Secure      rwxl

Peripheral              Domain          Status
00 NRF_P0               Non-Secure      OK
01 NRF_CLOCK            Non-Secure      OK
02 NRF_RTC0             Non-Secure      OK
03 NRF_RTC1             Non-Secure      OK
04 NRF_NVMC             Non-Secure      OK
05 NRF_UARTE1           Non-Secure      OK
06 NRF_UARTE2           Secure          SKIP
07 NRF_TWIM2            Non-Secure      OK
08 NRF_SPIM3            Non-Secure      OK
09 NRF_TIMER0           Non-Secure      OK
10 NRF_TIMER1           Non-Secure      OK
11 NRF_TIMER2           Non-Secure      OK
12 NRF_SAADC            Non-Secure      OK
13 NRF_PWM0             Non-Secure      OK
14 NRF_PWM1             Non-Secure      OK
15 NRF_PWM2             Non-Secure      OK
16 NRF_PWM3             Non-Secure      OK
17 NRF_WDT              Non-Secure      OK
18 NRF_IPC              Non-Secure      OK
19 NRF_VMC              Non-Secure      OK
20 NRF_FPU              Non-Secure      OK
21 NRF_EGU1             Non-Secure      OK
22 NRF_EGU2             Non-Secure      OK
23 NRF_DPPIC            Non-Secure      OK
24 NRF_GPIOTE1          Non-Secure      OK
25 NRF_REGULATORS       Non-Secure      OK

SPM: NS image at 0x1c200
SPM: NS MSP at 0x20020620
SPM: NS reset vector at 0x1d151
SPM: prepare to jump to Non-Secure image.
*** Booting Zephyr OS build v2.3.0-rc1-ncs1  ***
MCUBOOT IMAGE VERSION: 1.0.0
Hello World! nrf9160dk_nrf9160

So the downgrade prevention should work fine in NCS v1.3.0. 

I guess the issue is with the file app_update.bin from your AWS "nrfconnectsdk.s3.eu-central-1.amazonaws.com". 

How do you know what version app_update.bin using, and that it is less than 1.0.0?

Please create a new app_update.bin  (should be generated into <application>/build/zephyr/app_update.bin) with CONFIG_MCUBOOT_IMAGE_VERSION="0.0.0" and upload it to <your cloud server>, then try again.