Zymkey4 problem with ECDH

1

I think Zymbit should consider to add example for key exchange like the use of ecdh.
Now I get running error message with just calling

zymkey.client.ecdh(0,0)

Error from init.py line 936
dc = (c_ubyte * derived_key_size).from_address(derived_key.value)
TypeError: integer expected

I observed that dervied_key.value is None.

What should I do share key for two pi with different zymkey4? Could anybody give me a piece of example in how to use ecdh?

Also the C/C++ API example is none… Why the bar in using Zymbit products is so “High”?

2

@ChrisCCF The ZYMKEY4 does not support ECDH. From the API docs,

Derive a key or a pre-master secret from an ECDH operation. (Supported Devices: HSM6, Secure Compute Module).

See this table for feature comparison.

3

Thanks to your reply.

I had been tried the zymkey 4i.

I notice that the API used in this module could mainly deal with local problem.

If I would like to establish a secure data exchange through network, I would need to use HSM6?

I read the spec from HSM6. It covered the whole pin out for raspberry pi. Does it mean it utlized all GPIO? Could I still use the GPIO for connecting other device with HSM6 on top?