(C) 2018 University of Bristol, Bar-Ilan University. See License.txt

This repository contains the code to benchmark ORAM in SPDZ-BMR as used for the Eurocrypt 2018 paper by Marcel Keller and Avishay Yanay.

Preface:

This implementation only allows to benchmark the data-dependent phase. The data-independent and function-independent phases are emulated insecurely. The software should be considered an academic prototype, and we will only give advice on rurunning the examples below.

Requirements:

• GCC (tested with 7.2) or LLVM (tested with 3.8)
• MPIR library, compiled with C++ support (use flag --enable-cxx when running configure)
• libsodium library, tested against 1.0.11
• CPU supporting AES-NI and PCLMUL
• Python 2.x
• If using macOS, Sierra or later

To compile:

1. Edit CONFIG or CONFIG.mine:

• Add the following line at the top: MY_CFLAGS = -DINSECURE
• For processors without AVX (e.g., Intel Atom) or for optimization, set ARCH = -march=<architecture>.

2. Run make bmr (use the flag -j for faster compilation multiple threads). Remember to run make clean first after changing CONFIG or CONFIG.mine.

Configure the parameters:

1. Edit Program/Source/gc_oram.mpc to change size and to choose Circuit ORAM or linear scan without ORAM.
2. Run ./compile.py -D gc_oram.

Run the protocol:

• Run everything locally: Scripts/bmr-program-run.sh gc_oram.
• Run on different hosts: Scripts/bmr-program-run-remote.sh gc_oram <host1> <host2> [...]

To run with more than two parties, change CFLAGS = -DN_PARTIES=<n> in CONFIG, and compile again after make clean.