dk.alexandra.fresco.lib.helper.bristol.BristolCircuit.java Source code

Introduction

Here is the source code for dk.alexandra.fresco.lib.helper.bristol.BristolCircuit.java

Source

/*******************************************************************************
 * Copyright (c) 2015 FRESCO (http://github.com/aicis/fresco).
 *
 * This file is part of the FRESCO project.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * FRESCO uses SCAPI - http://crypto.biu.ac.il/SCAPI, Crypto++, Miracl, NTL,
 * and Bouncy Castle. Please see these projects for any further licensing issues.
 *******************************************************************************/
package dk.alexandra.fresco.lib.helper.bristol;

import org.apache.commons.lang.ArrayUtils;

import dk.alexandra.fresco.framework.MPCException;
import dk.alexandra.fresco.framework.NativeProtocol;
import dk.alexandra.fresco.framework.Protocol;
import dk.alexandra.fresco.framework.value.SBool;
import dk.alexandra.fresco.framework.value.Value;

/**
 * A circuit that is based on Bristol circuits, i.e., it reads a textual
 * description of a circuit in Bristol format (see
 * https://www.cs.bris.ac.uk/Research/CryptographySecurity/MPC/) using the
 * BristolCircuitParser.
 * 
 */
public class BristolCircuit implements Protocol {

    private SBool[] in1, in2, out;

    private BristolCircuitParser parser;

    private int pos = 0;

    public BristolCircuit(BristolCircuitParser parser, SBool[] in1, SBool[] in2, SBool[] out) {
        this.in1 = in1;
        this.in2 = in2;
        this.out = out;
        this.parser = parser;
    }

    @Override
    public int getNextProtocols(NativeProtocol[] protocols, int pos) {
        // TODO: This is a bit hacky. 
        // It only works if the BasicLogicFactory given to CircuitParser
        // produces circuits for AND, XOR, NOT that are native protocols.
        // Otherwise, more book-keeping is needed here.
        NativeProtocol[] tmp = new NativeProtocol[5];
        Protocol[] c = new Protocol[1];
        while (pos < protocols.length) {
            int resCircuit = this.parser.getNext(c, 0);
            if (resCircuit == 0) {
                // The next circuit has input that depends on some unReady input, or end of circuit reached. End batch.
                break;
            } else if (resCircuit != 1) {
                throw new MPCException("Weird, should give one circuit exactly, pos: " + resCircuit);
            }

            // Got exactly one circuit.
            int res = c[0].getNextProtocols(tmp, 0);
            if (res == 0) {
                break; // End of circuit reached.
            }
            if (res != 1)
                throw new MPCException(
                        "Seems like you gave circuit parser a logic factory with non-native XOR,AND,NOT protocols");
            protocols[pos] = tmp[0];
            pos++;
            this.pos++;
        }
        //System.out.println("Returning protocols; internal pos: " + this.pos);
        return pos;
    }

    @Override
    public boolean hasNextProtocols() {
        return this.pos < this.parser.getNoOfGates();
    }

    @Override
    public Value[] getInputValues() {
        return (Value[]) ArrayUtils.addAll(this.in1, this.in2);
    }

    @Override
    public Value[] getOutputValues() {
        return this.out;
    }

}