Hello,
I am trying to integrate an STSAFE-A110 chip into my product for keys/data securely storage.
The communication with the chip works fine (approved by simple command as echo or generate_random).
So I tried to generate a key in a local envelope key slot (first step of command flow in the "Local envelope wrapping/unwrapping" process). For that I queried the STSAFE-A110 to randomly generate a local envelope key in slot #0 and #1, using the STSAFEA_CMD_GENERATE_KEY (0x11) command.
> 11 07 00 00 AF C1
> 11 07 01 00 B6 19
The chip answers OK as status code (correct crc) but I missed to keep data.
But when I query the STSAFE-A110 to retrieve local envelope keys information (slot number, presence & key length), I get a key presence flag to 1 but with zeroed key length for the 2 slots.
> 14 07 89 09
< 00 00 09 02 00 01 00 01 01 00 FC 88
status=OK(0x00)
slot_nb=2
Slot #0:
- key_presence=1
- key_length=0
Slot #1:
- key_presence=1
- key_length=0
How is it possible?
Unable afterwards to generate again a key in a local envelope key slot (UNSATISFIED_ACCESS_CONDITION as status return code).
Could you please help me?
- Is the chip bricked?
- Is the "Local envelope wrapping/unwrapping" process the good one for secret securely storage?
- How to do to get out of this situation?
