SPDZ Connector
This repository gives a c++ codebase example for connecting to MP-SPDZ engines. To start with the example, please clone the MP-SPDZ library with the specific branch.
MP-SPDZ Installation
After cloning the MP-SPDZ library, replace two files with in the spdz_replace folder:
one is the Makefile file to ${SPDZ_HOME}/, the other is the Setup.h file to
${SPDZ_HOME}/Math/Setup.h. For the latter file, need to change the prefix PREP_DIR
to the cloned MP-SPDZ home. Besides, to run the MP-SPDZ programs in an insecure mode,
copy the CONFIG.mine file to ${SPDZ_HOME}/.
Next, run the following scripts under the MP-SPDZ home to install MP-SPDZ as a library, and generate the necessary certificates, executables, and so on.
# clean the folder
make clean
# install the MP-SPDZ dependency library mpir
make mpir
# install MP-SPDZ as library, will generate libSPDZ.a and libSPDZ.so
make lib
# compile semi-party.x for running additive secret sharing protocol
make -j 8 Player-Online.x
make -j 8 Fake-Offline.x
make -j 8 semi-party.x
# setup certificates and keys, assume there are three SPDZ parties
bash Scripts/setup-clients.sh 3
bash Scripts/setup-online.sh 3 128 128
bash Scripts/setup-ssl.sh 3 128 128
bash Scripts/setup-online.sh 3 192 128
bash Scripts/setup-ssl.sh 3 192
Then, copy the add_computation.mpc MPC program to
${SPDZ_HOME}/Programs/Source/ folder, and compile it using the following
script.
./compile.py Programs/Source/add_computation.mpc
Finally, open three terminals and run the following scripts in the three
terminals to start the MPC computing engines, where -p denotes the MPC
party id, -N denotes the total MPC party number, more notations can be
found in the MP-SPDZ page.
./semi-party.x -F -N 3 -I -p 0 add_computation
./semi-party.x -F -N 3 -I -p 1 add_computation
./semi-party.x -F -N 3 -I -p 2 add_computation
After that, if seeing the following in the terminals, then the MPC engines are started correctly.
Start listening on thread 140153657132800
Party 1 is listening on port 14001 for external client connections.
Listening for socket connections on base port 14000
Starting a new iteration.
Thread 140153657132800 found server.
Connector
For the connector, need to change the SPDZ_HOME in CMakeLIsts.txt to the
cloned path. Then, can compile the program using the following scripts:
mkdir build
cmake -Bbuild -H.
cd build/
make
Next, go to the build path, and run three parties in three terminals as follows, where the first argument is the number of total parties, and the second is the party id.
./spdz_codebase 3 0
./spdz_codebase 3 1
./spdz_codebase 3 2
These three parties will connect to the three MPC engines, and each party will send a private value to the MPC engines, the MPC engines aggregate the numbers and return the result. If seeing the following result, the example is correct.
Hello, World!
begin connect to spdz parties
party_num = 3
Set up socket connections for 0-th spdz party succeed, sockets = 0x6120000031c0, port_num = 14000.
Set up socket connections for 1-th spdz party succeed, sockets = 0x6120000061c0, port_num = 14001.
Set up socket connections for 2-th spdz party succeed, sockets = 0x612000007cc0, port_num = 14002.
Finish setup socket connections to spdz engines.
Using prime 170141183460469231731687303715885907969
Finish initializing gfp field.
receive spdz computation result
Receive mpc computation result from the SPDZ engine
v = 6