Pass a TCP connection into a SGX enclave

[johnsnow]

Hello everyone,

I'm wondering if it is possible to pass a TCP connection into a SGX enclave.
Lets say there is a server A (outside of the enclave) that listens on a TCP port and accepts incoming connections.
Now there is also a server B (inside the enclave). Can server A accept a TCP connection, and then pass the file descriptor to server B in the enclave, so that server B can read and write to that connection?

If server B was not in an enclave, this would be possible. Server A could send the file descriptor from the TCP connection to server B via UNIX sockets and the SCM_RIGHTS mechanism. This will cause the kernel to intercept the message, and it will copy the file descriptor into the receiving process's file descriptor table. 
However, this requires the UNIX commands sendmsg() and recvmsg(), which are not supported in gramine: https://gramine.readthedocs.io/en/latest/devel/features.html

Is there another way of achieving this?

Thank you!

[Benny_Intel]

Hello,

For Gramine related questions, please use one of the Gramine support channels listed on https://gramine.readthedocs.io/en/stable/#getting-help.

Best regards,
Benny 

[johnsnow]

Thanks for the quick response. I'm actually not using Gramine. This is more of a general SGX question.