An OpenSSL engine implementation that utilizes a SGX keystore server. Current implementation only supports RSA keys up to 4096 bits.

The design, implementation and evaluation of the system is described in our Computer & Security journal 2021 paper.

• An Intel SGX capable CPU
• Intel(R) Software Guard Extensions for Linux* OS
• Intel SGX SSL
• OpenSSL 1.1+

1. Download and Compile Intel SGX SSL
2. Modify the file buildenv.mk in the src folder so that the variable SGXSSL points to root folder of Intel SGX SSL.
3. Run make inside the src folder

You must add the compiled engine to your openssl.cnf file like so:

[openssl_init]
engines=engine_section

[engine_section]
sgxkeystore = sgxkeystore_section

[sgxkeystore_section]
engine_id = sgxkeystore
dynamic_path = /path/to/sgxkeystore.so
init = 0

1. Generating a key:
   • Generating using OpenSSL normally ane seal it by running ./UtilityApp <key_file>
   • or
   • Generate a RSA 4096 bit key using the Utility app ./UtilityApp --gen <key_file>
2. Run the server
3. To use the key in the enclave the following path must be specified: sgxkeystore:/path/to/key.pem.sealed>

Build the Apache Web Server with the SSL module enabled and with the following patch applied: patch