In December (2017) I had SGX remote attestation working on a Thinkpad T470 (20HD) under Linux.
On the 27th December 2017 Lenovo released a BIOS update 1.44 which addressed CVE-2017-5715.
Since installing the BIOS update attestation now fails, with the following messages:
: Error, call sgx_get_extended_epid_group_id fail: 0x4001
: sgx_create_enclave() needs the AE service to get a launch token
I assume the Spectre fix CVE-2017-5715 has changed the time taken to perform an operation which has caused the AE service to be declared as not running.
The Intel SGX platform software is trying to reprovision because of the BIOS update (these fixes result in a TCB recovery). Error 0x4001 in this context means the request to the AE service timed out.
Thanks for the response John looking at the aesmd service I get the following
$ service aesmd status
● aesmd.service - Intel(R) Architectural Enclave Service Manager
Loaded: loaded (/lib/systemd/system/aesmd.service; enabled; vendor preset: enabled)
Active: activating (auto-restart) (Result: exit-code) since Wed 2018-01-10 20:44:21 GMT; 5s ago
Process: 2770 ExecStart=/opt/intel/sgxpsw/aesm/aesm_service (code=exited, status=0/SUCCESS)
Process: 2767 ExecStartPre=/bin/chmod 0755 /var/run/aesmd/ (code=exited, status=0/SUCCESS)
Process: 2763 ExecStartPre=/bin/chown -R aesmd:aesmd /var/run/aesmd/ (code=exited, status=0/SUCCESS)
Process: 2759 ExecStartPre=/bin/mkdir -p /var/run/aesmd/ (code=exited, status=0/SUCCESS)
Process: 2748 ExecStartPre=/opt/intel/sgxpsw/aesm/linksgx.sh (code=exited, status=0/SUCCESS)
Main PID: 2772 (code=exited, status=1/FAILURE)
<b>Jan 10 20:44:21 arthur-ThinkPad-T470 systemd: aesmd.service: Unit entered failed state.
Jan 10 20:44:21 arthur-ThinkPad-T470 systemd: aesmd.service: Failed with result 'exit-code'.</b>
I am not using a proxy and changing following line in cat /etc/aesmd.conf has no effect
#proxy type = direct #direct type means no proxy used
What could be causing the aesmd service to fail?
OK now fixed! The aesmd service was failing because the sgx driver was not running.
I had updated the kernel version, which then required the sgx driver to be reinstalled.
Thanks for the pointers.