Trusty Client Applications in Non-secure World

Hello,
Are there any examples of Trusty client applications?
I can run hwkey-app of hwkey-agent, but I’m not sure how to implement other client applications for skel, skel2 and timer.
I implemented a trusted application skel referencing NVIDIA Jetson Linux Developer Guide, and then tried to develop a client application for skel referencing hwkey-app. But I’m not sure a tipc service name of skel.

hello tsunakai,

please access L4T sources package for the public release sources.
you might also check documentation, please refer to Trusted Application Development.
thanks

Hello JerryChang,

Thank you for your reply.
I compiled and implemented L4T sources package to Jetson AGX Xavier.
In this source, there is only one client application hwkey-app for hwkey-agent that is CA_sample.
Basically, I would like to know CA_sample for skel.

hello tsunakai,

there’s already TA/CA samples, please check readme files for details.
thanks

TA, trusty/app/sample/hwkey-agent/README
CA, trusty/app/sample//hwkey-agent/CA_sample/README

Hello JerryChang,

According to your reply, I understood there’s only one CA sample that is hwkey-agent.
I have already read their READMEs, but there are no details about how to develop new CA sample, only how to compile and use hwkey-app.
In addition, the documentation of Trusted Application Development focuses on only TA.
I would like to develop CA samples for other TA samples such as skel, skel2 and timer.
Thank you.

hello tsunakai,

there are three simple TA demos, ske1, ske2, and timer demonstrate “Hello, world” in Trusty.
there’s NO specific rules for the implementation of CA. you may implement CA as you want once the application model and TIPC interface are defined.

FYI,
please refer to below steps or guides to implement or extend more functions into it.

  • define the interface of TIPC which includes the service name and the format of data packets
  • create the IPC service: please reference the sample code and the API reference guide, https://source.android.com/security/trusty/trusty-ref.
  • the API reference guide can help you to understand to create IPC communication between TA/CA
  • Make sure your secure model of the application that you want to implement. i.e. don’t leak sensitive data outside secure world

Hello JerryChang,

I got it. Thank you.
Basically, the three simple TA demos are incomplete in case of calling just them from CA like hwkey-agent. I should modify them to define the TIPC interface of the TA demos in advance. And then, I can implement CA for the TA demos. I have done it. Thanks a lot.

hello tsunakai,
I know that you can run hwkey_app in hwkey_agent, so can you run hwkey_agent in this directory?
if you can run correctly, please tell me!
thanks