topic Hi Junli, in Intel Confidential Computing

Remote EPID-Attestation: LD_LIBRARY_PATH problems

Dix__Isabella — Thu, 26 Mar 2020 17:14:24 GMT

Hi,

I am trying to run this example using my own dev EPID license (aquired here). I followed the README but am uncertain as to how I should set LD_LIBRARY_PATH when running the client.

1) At first I did not set LD_LIBRARY_PATH at all and got the message "This system does not support Intel SGX."

2) Then I debugged a bit and found that the client tries to find the libraries "libsgx_uae_service.so" and "libsgx_urts.so" but cannot due to the unset LD_LIBRARY_PATH. So I ran locate for both and received the following results

locate libsgx_urts.so
/opt/intel/sgxsdk/lib64/libsgx_urts.so
/usr/lib/x86_64-linux-gnu/libsgx_urts.so
locate libsgx_uae_service.so
/opt/intel/sgxsdk/lib64/libsgx_uae_service.so

So I set LD_LIBRARY_PATH=/opt/intel/sgxsdk/lib64. But then I get the message "Please use the correct uRTS library from PSW package."

3) So I googled a bit and found this issue where a user says "Do not set LD_LIBRARY_PATH=/opt/intel/sgxsdk/lib64/ ". But since "libsgx_uae_service.so" is only present in this folder I could not, but instead I set it to LD_LIBRARY_PATH=/usr/lib/x86_64-linux-gnu/:/opt/intel/sgxsdk/lib64/ so the sample would at least find the uRTS at the correct point.
Basically this is working now, but the enclave always returns m1.gid=0 (not EGID, the gid which should not be 0 in HW mode, which I used to built it). I suspect that it has something to do with the fact that the LD_LIBRARY_PATH also contains the libraries for SGX_MODE=SIM but I do not know how to get around linking /opt/intel/sgxsdk/lib64/

If you need any further information about installation/configuration/host or have any other ideas: Please go ahead, however I don't know how to get this example to work.

Grateful for any help,

Best regards,

Isabella

The libraries in the /opt

Junli_S_Intel — Fri, 27 Mar 2020 01:26:47 GMT

The libraries in the /opt/intel/sgxsdk/lib64 are used in compile time. If you want to execute your App, you need install PSW package: all of needed libraries has been installed in the folder /user/lib/x86_64-linux-gnu

Hi Junli,

Dix__Isabella — Fri, 27 Mar 2020 11:06:00 GMT

Hi Junli,

thanks for your answer!

Should I install that manually? I installed PSW according to the installation guide using

"sudo apt-get install libsgx-epid libsgx-urts"

I also tried installing libsgx-epid-dev to no avail. By manually I mean installing it from here

https://download.01.org/intel-sgx/sgx-linux/2.8/distro/ubuntu16.04-server/debian_pkgs/libs/libsgx-uae-service/

Update: I directly installed

Dix__Isabella — Fri, 27 Mar 2020 14:11:13 GMT

Update: I directly installed this package, it said unmet dependencies, so I decided to install with apt and dependecies and still after that I get

> locate libsgx_uae_service.so
/opt/intel/sgxsdk/lib64/libsgx_uae_service.so

and

> locate libsgx_uae_service
/opt/intel/sgxsdk/lib64/libsgx_uae_service.so
/opt/intel/sgxsdk/lib64/libsgx_uae_service_sim.so
/opt/intel/sgxsdk/pkgconfig/libsgx_uae_service.pc
/opt/intel/sgxsdk/pkgconfig/libsgx_uae_service_sim.pc
/opt/intel/sgxsdk/sdk_libs/libsgx_uae_service_sim.so

Is it related to the fact, that I use the machine for development as well and SDK and the driver are installed on this machine?

My bad. locate doesn't seem

Dix__Isabella — Fri, 27 Mar 2020 16:06:17 GMT

My bad. locate doesn't seem to reliably find the files. After this installation they are now present in /usr/lib/x86_64-linux-gnu and when I set that for LD_LIBRARY_PATH everything works fine.

This can be marked as resolved. Thanks Junli!

I am grad to see you have

Junli_S_Intel — Fri, 27 Mar 2020 16:34:42 GMT

I am grad to see you have resolved the issue. Enjoy your SGX trip. :)