private static async Task RunSecureComputationPartyAsync(int localPartyId, BitArray localInput)
{
Console.WriteLine($"Starting party {localPartyId}...");
using IMultiPartyNetworkSession session = await TcpMultiPartyNetworkSession.EstablishLoopbackAsync(
new Party (localPartyId),
StartPort,
NumberOfParties
);
using CryptoContext cryptoContext = CryptoContext.CreateDefault();
IObliviousTransfer obliviousTransfer = new NaorPinkasObliviousTransfer(
SecurityParameters.CreateDefault768Bit(),
cryptoContext
);
IMultiplicativeSharing multiplicativeSharing = new ObliviousTransferMultiplicativeSharing(
obliviousTransfer,
cryptoContext
);
SecretSharingSecureComputation computation = new SecretSharingSecureComputation(
session,
multiplicativeSharing,
cryptoContext
);
Stopwatch stopwatch = Stopwatch.StartNew();
SetIntersectionSecureProgram secureProgram = new SetIntersectionSecureProgram(NumberOfParties, NumberOfElements);
object[] outputPrimitives = await secureProgram.EvaluateAsync(computation, new object[] { localInput });
BitArray intersection = (BitArray)outputPrimitives[0];
BigInteger count = (BigInteger)outputPrimitives[1];
stopwatch.Stop();
Console.WriteLine();
Console.WriteLine($"Completed protocol as {session.LocalParty.Name} in {stopwatch.ElapsedMilliseconds} ms.");
Console.WriteLine($" Local input: {localInput.ToBinaryString()}");
Console.WriteLine($" Computed intersection: {intersection.ToBinaryString()}");
Console.WriteLine($" Computed number of matches: {count}");
Console.WriteLine();
Console.WriteLine("Press any key to exit.");
Console.ReadKey(true);
}
private static void PerformSecureComputation(IMultiPartyNetworkSession session, BitArray expectedOutput)
{
BitArray localInput = Inputs[session.LocalParty.Id];
using CryptoContext cryptoContext = CryptoContext.CreateDefault();
IObliviousTransfer obliviousTransfer = new NaorPinkasObliviousTransfer(
new SecurityParameters(47, 23, 4, 1, 1),
cryptoContext
);
IMultiplicativeSharing multiplicativeSharing = new ObliviousTransferMultiplicativeSharing(
obliviousTransfer,
cryptoContext
);
SecretSharingSecureComputation computation = new SecretSharingSecureComputation(
session,
multiplicativeSharing,
cryptoContext
);
SetIntersectionCircuitRecorder circuitRecorder = new SetIntersectionCircuitRecorder(
session.NumberOfParties,
localInput.Length
);
CircuitBuilder circuitBuilder = new CircuitBuilder();
circuitRecorder.Record(circuitBuilder);
ForwardCircuit circuit = new ForwardCircuit(circuitBuilder.CreateCircuit());
BitArray actualOutput = computation
.EvaluateAsync(circuit, circuitRecorder.InputMapping, circuitRecorder.OutputMapping, localInput)
.Result;
EnumerableAssert.AreEqual(
expectedOutput,
actualOutput
);
}
