Secure Firmware

I am trying to achieve secure firmware in ardupilot(master version) using the below documentation:

When following the above documentation i got the error while running the below command(after successfully building secure bootloader)

./waf copter

I got the below error:

Can someone guide me ?

899/903] Generating bin/arducopter.bin
[900/903] app_descriptor build/CubeOrange/bin/arducopter.bin
Waf: Leaving directory `/home/vinoth1/Original-codes/Ardupilot/ardupilot/build/CubeOrange’
Build failed
Traceback (most recent call last):
File “/home/ardupilot/modules/waf/waflib/”, line 348, in process
ret =
File “Tools/ardupilotwaf/”, line 296, in run
desc = struct.pack(‘<IIII76s’, crc1, crc2, len(img), githash, sig)
error: argument for ‘s’ must be a string

Have you come over this error because for me it shows the same…

I just followed the installation procedures again and it is now working fine for me now.

Can you tell me how you corrected it? I am still unable to get it!

Uninstall and reinstall again by following the steps given here