Feldman's VSS

destributed-key-generation/build.gradle

@@ -0,0 +1,220 @@
+
+plugins {
+  id "us.kirchmeier.capsule" version "1.0.1"
+  id 'com.google.protobuf' version '0.7.0'
+}
+
+apply plugin: 'java'
+apply plugin: 'eclipse'
+apply plugin: 'idea'
+
+apply plugin: 'maven-publish'
+
+// Uncomment the lines below to define an application
+// (this will also allow you to build a "fatCapsule" which includes
+// the entire application, including all dependencies in a single jar)
+//apply plugin: 'application'
+//mainClassName='your.main.ApplicationClass'
+
+// Is this a snapshot version?
+ext { isSnapshot = false } 
+
+ext {
+        groupId = 'org.factcenter.meerkat'
+        nexusRepository = "https://cs.idc.ac.il/nexus/content/groups/${isSnapshot ? 'unstable' : 'public'}/"
+        
+        // Credentials for IDC nexus repositories (needed only for using unstable repositories and publishing)
+        // Should be set in ${HOME}/.gradle/gradle.properties
+        nexusUser =  project.hasProperty('nexusUser') ? project.property('nexusUser') : ""
+        nexusPassword = project.hasProperty('nexusPassword') ? project.property('nexusPassword') : ""
+}
+
+description = "TODO: Add a description"
+
+// Your project version
+version = "0.0"
+
+version += "${isSnapshot ? '-SNAPSHOT' : ''}"
+
+
+dependencies {
+    // Meerkat common
+    compile project(':meerkat-common')
+
+    // Logging
+    compile 'org.slf4j:slf4j-api:1.7.7'
+    runtime 'ch.qos.logback:logback-classic:1.1.2'
+    runtime 'ch.qos.logback:logback-core:1.1.2'
+
+    // Google protobufs
+    compile 'com.google.protobuf:protobuf-java:3.+'
+
+    testCompile 'junit:junit:4.+'
+
+    runtime 'org.codehaus.groovy:groovy:2.4.+'
+}
+
+
+/*==== You probably don't have to edit below this line =======*/
+
+// Setup test configuration that can appear as a dependency in
+// other subprojects
+configurations {
+    testOutput.extendsFrom (testCompile)
+}
+
+task testJar(type: Jar, dependsOn: testClasses) {
+    classifier = 'tests'
+    from sourceSets.test.output
+}
+
+artifacts {
+    testOutput testJar
+}
+
+// The run task added by the application plugin
+// is also of type JavaExec.
+tasks.withType(JavaExec) {
+    // Assign all Java system properties from
+    // the command line to the JavaExec task.
+    systemProperties System.properties
+}
+
+
+protobuf {
+    // Configure the protoc executable
+    protoc {
+    // Download from repositories
+        artifact = 'com.google.protobuf:protoc:3.+'
+    }
+}
+
+
+idea {
+    module {
+        project.sourceSets.each { sourceSet ->
+
+            def srcDir = "${protobuf.generatedFilesBaseDir}/$sourceSet.name/java"
+
+            println "Adding $srcDir"
+            // add protobuf generated sources to generated source dir.
+            if ("test".equals(sourceSet.name)) {
+                testSourceDirs += file(srcDir)
+            } else {
+                sourceDirs += file(srcDir)
+            }
+            generatedSourceDirs += file(srcDir)
+
+        }
+
+	    // Don't exclude build directory
+	    excludeDirs -= file(buildDir)
+    }
+}
+
+
+/*===================================
+ *        "Fat" Build targets
+ *===================================*/
+
+
+if (project.hasProperty('mainClassName') && (mainClassName != null)) {
+
+    task mavenCapsule(type: MavenCapsule) {
+        description = "Generate a capsule jar that automatically downloads and caches dependencies when run."
+        applicationClass mainClassName
+        destinationDir = buildDir
+    }
+
+    task fatCapsule(type: FatCapsule) {
+        description = "Generate a single capsule jar containing everything. Use -Pfatmain=... to override main class"
+
+        destinationDir = buildDir
+
+        def fatMain = hasProperty('fatmain') ? fatmain : mainClassName
+
+        applicationClass fatMain
+
+        def testJar = hasProperty('test')
+
+        if (hasProperty('fatmain')) {
+            appendix = "fat-${fatMain}"
+        } else {
+            appendix = "fat"
+        }
+
+        if (testJar) {
+            from sourceSets.test.output
+        }
+    }
+}
+
+
+/*===================================
+ *        Repositories
+ *===================================*/
+
+repositories {
+        
+        // Prefer the local nexus repository (it may have 3rd party artifacts not found in mavenCentral)
+        maven { 
+            url nexusRepository
+            
+            if (isSnapshot) {
+                credentials { username 
+                    password 
+
+                    username nexusUser
+                    password nexusPassword 
+                }
+            }
+        }
+
+        // Use local maven repository
+        mavenLocal()
+
+        // Use 'maven central' for other dependencies.
+        mavenCentral()
+}
+
+task "info" << {
+        println "Project: ${project.name}"
+println "Description: ${project.description}"
+        println "--------------------------"
+        println "GroupId: $groupId"
+        println "Version: $version (${isSnapshot ? 'snapshot' : 'release'})"
+        println ""
+}
+info.description 'Print some information about project parameters'
+
+
+/*===================================
+ *        Publishing
+ *===================================*/
+
+publishing {
+    publications {
+        mavenJava(MavenPublication) {
+            groupId project.groupId
+            pom.withXml {
+                asNode().appendNode('description', project.description)
+            }
+            from project.components.java
+
+        }
+    }
+    repositories {
+        maven {
+            url "https://cs.idc.ac.il/nexus/content/repositories/${project.isSnapshot ? 'snapshots' : 'releases'}"
+            credentials { username 
+                password 
+
+                username nexusUser
+                password nexusPassword 
+            }
+        }
+    }
+}
+
+
+

destributed-key-generation/src/main/java/FeldmanVerifiableSecretSharing/VerifiableSecretSharing.java

@@ -0,0 +1,54 @@
+package FeldmanVerifiableSecretSharing;
+
+import ShamirSecretSharing.SecretSharing;
+import org.bouncycastle.util.Arrays;
+import org.factcenter.qilin.primitives.concrete.Zpstar;
+
+import java.math.BigInteger;
+import java.util.Random;
+
+/**
+ * Created by Tzlil on 1/27/2016.
+ */
+public class VerifiableSecretSharing extends SecretSharing {
+
+    private final BigInteger[] commitments;
+    private final BigInteger g;
+
+    public VerifiableSecretSharing(Zpstar zpstar, int t, int n, BigInteger s, Random random) {
+        super(zpstar, t, n, s, random);
+        this.g = BigInteger.ONE; //ToDO zpstar.getGenerator()
+        this.commitments = generateCommitments();
+    }
+
+    private BigInteger[] generateCommitments() {
+        BigInteger[] coefficients = polynomial.getCoefficients();
+        BigInteger[] commitments = new BigInteger[coefficients.length];
+        for (int i = 0 ; i < commitments.length;i++){
+            commitments[i] = zpstar.multiply(g,coefficients[i]);
+        }
+        return commitments;
+    }
+
+    public BigInteger verify(int i) throws Exception {
+        if(i < 1 || i > n){
+            throw new Exception();
+        }
+        BigInteger v = BigInteger.ONE;
+        int power = 1;
+        for (int j = 0 ; j < commitments.length ; j ++){
+            v.multiply(commitments[i].pow(power));
+            power *=i;
+        }
+        return zpstar.add(BigInteger.ONE,v);
+    }
+
+
+    public BigInteger getG() {
+        return g;
+    }
+
+    public BigInteger[] getCommitments() {
+        return Arrays.clone(commitments);
+    }
+}

destributed-key-generation/src/main/java/ShamirSecretSharing/Polynomial.java

@@ -0,0 +1,119 @@
+package ShamirSecretSharing;
+
+import org.bouncycastle.util.Arrays;
+import org.factcenter.qilin.primitives.concrete.ECGroup;
+
+import java.math.BigInteger;
+
+/**
+ * Created by Tzlil on 1/27/2016.
+ */
+public class Polynomial {
+
+    private static final Polynomial ZERO = new Polynomial(new BigInteger[]{BigInteger.ZERO});
+    private static final Polynomial ONE = new Polynomial(new BigInteger[]{BigInteger.ONE});
+    private final int degree;
+    private final BigInteger[] coefficients;
+
+    public Polynomial(BigInteger[] coefficients) {
+        this.degree = coefficients.length - 1;
+        this.coefficients = coefficients;
+    }
+
+    public Polynomial(Polynomial polynomial) {
+        this.degree = polynomial.getDegree();
+        this.coefficients = polynomial.getCoefficients();
+    }
+
+    public BigInteger image(BigInteger x){
+        BigInteger result = BigInteger.ZERO;
+        BigInteger power = BigInteger.ONE;
+        for(int i = 0 ; i <= degree ; i++){
+            result.add(coefficients[i].multiply(power));
+            power.multiply(x);
+        }
+        return result;
+    }
+
+    public static Polynomial interpolation(Point[] points){
+        Polynomial[] factors = new Polynomial[points.length];
+        for (int i = 0 ; i < factors.length ; i++){
+            factors[i] = new Polynomial(new BigInteger[]{BigInteger.ONE,points[i].x}); // X - Xi
+        }
+        Polynomial result = ZERO;
+        BigInteger constant;
+        Polynomial product;
+        for (int i = 0 ; i < points.length; i++){
+            constant = points[i].y;
+            product = ONE;
+            for (int j = 0 ; j < points.length; j ++){
+                if(i != j ) {
+                    constant = constant.divide(points[i].x.subtract(points[j].x));
+                    product = product.mul(factors[j]);
+                }
+            }
+            result.add(product.mul(constant));
+        }
+        return result;
+    }
+
+    public Polynomial add(Polynomial other){
+        Polynomial bigger,smaller;
+        if(this.degree < other.degree){
+            bigger = other;
+            smaller = this;
+        }else{
+            bigger = this;
+            smaller = other;
+        }
+        BigInteger[] coefficients = bigger.getCoefficients();
+
+        for (int i = 0; i <= smaller.degree ; i++){
+            coefficients[i] = smaller.coefficients[i].add(bigger.coefficients[i]);
+        }
+        return  new Polynomial(coefficients);
+    }
+
+    public Polynomial mul(BigInteger constant){
+
+        BigInteger[] coefficients = this.getCoefficients();
+
+        for (int i = 0; i <= this.degree ; i++){
+            coefficients[i] = constant.multiply(coefficients[i]);
+        }
+        return  new Polynomial(coefficients);
+    }
+
+    public Polynomial mul(Polynomial other){
+
+        BigInteger[] coefficients = new BigInteger[this.degree + other.degree + 1];
+        java.util.Arrays.fill(coefficients,BigInteger.ZERO);
+
+        for (int i = 0; i <= this.degree ; i++){
+            for (int j = 0; j <= other.degree; j++){
+                coefficients[i+j] = coefficients[i+j].add(this.coefficients[i].multiply(other.coefficients[j]));
+            }
+        }
+        return  new Polynomial(coefficients);
+    }
+
+
+    public BigInteger[] getCoefficients() {
+        return Arrays.clone(coefficients);
+    }
+    public int getDegree() {
+        return degree;
+    }
+
+
+    public static class Point{
+        public final BigInteger x;
+        public final BigInteger y;
+
+        public Point(BigInteger x, BigInteger y) {
+            this.x = x;
+            this.y = y;
+        }
+    }
+
+}

destributed-key-generation/src/main/java/ShamirSecretSharing/SecretSharing.java

@@ -0,0 +1,56 @@
+package ShamirSecretSharing;
+
+
+import org.factcenter.qilin.primitives.concrete.Zpstar;
+
+import java.math.BigInteger;
+import java.util.Random;
+
+/**
+ * Created by Tzlil on 1/27/2016.
+ */
+public class SecretSharing {
+    protected final Zpstar zpstar;
+    protected final int t;
+    protected final int n;
+    protected final Polynomial polynomial;
+
+    public SecretSharing(Zpstar zpstar, int t, int n, BigInteger s, Random random) {
+        this.zpstar = zpstar;
+        this.t = t;
+        this.n = n;
+        this.polynomial = generateRandomPolynomial(s,random);
+    }
+
+    private Polynomial generateRandomPolynomial(BigInteger s, Random random) {
+        BigInteger[] coefficients = new BigInteger[t + 1];
+        coefficients[0] = s;
+        for (int i = 1 ; i <= t; i++ ){
+            coefficients[i] = zpstar.sample(random);
+        }
+        return new Polynomial(coefficients);
+    }
+
+    //ToDo make it safe : permission to call this func + modulo calc
+    public Polynomial.Point getShare(int i) throws Exception {
+        if(i < 1 || i > n){
+            throw new Exception();
+        }
+        return new Polynomial.Point(BigInteger.valueOf(i), polynomial.image(BigInteger.valueOf(i)));
+    }
+
+    public static BigInteger getSecrete(Polynomial.Point[] shares){
+        Polynomial polynomial = Polynomial.interpolation(shares);
+        return polynomial.image(BigInteger.ZERO);
+    }
+
+    public int getThreshold() {
+        return t;
+    }
+
+    public int getN() {
+        return n;
+    }
+
+
+}

gradle/wrapper/gradle-wrapper.properties

@@ -1,7 +1,6 @@
-#Tue Aug 05 03:26:05 IDT 2014
+#Wed Jan 27 00:30:26 IST 2016
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.9-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.9-bin.zip
-distributionSha256Sum=4647967f8de78d6d6d8093cdac50f368f8c2b8038f41a5afe1c3bce4c69219a9

gradlew

@@ -42,11 +42,6 @@ case "`uname`" in
     ;;
 esac
 
-# For Cygwin, ensure paths are in UNIX format before anything is touched.
-if $cygwin ; then
-    [ -n "$JAVA_HOME" ] && JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
-fi
-
 # Attempt to set APP_HOME
 # Resolve links: $0 may be a link
 PRG="$0"
@@ -61,9 +56,9 @@ while [ -h "$PRG" ] ; do
     fi
 done
 SAVED="`pwd`"
-cd "`dirname \"$PRG\"`/" >&-
+cd "`dirname \"$PRG\"`/" >/dev/null
 APP_HOME="`pwd -P`"
-cd "$SAVED" >&-
+cd "$SAVED" >/dev/null
 
 CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
 
@@ -114,6 +109,7 @@ fi
 if $cygwin ; then
     APP_HOME=`cygpath --path --mixed "$APP_HOME"`
     CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
 
     # We build the pattern for arguments to be converted via cygpath
     ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`

meerkat-common/src/main/java/meerkat/crypto/concrete/ECElGamalEncryption.java

@@ -110,7 +110,7 @@ public class ECElGamalEncryption extends GlobalCryptoSetup implements Encryption
         Pair<ECPoint,ECPoint> randomizer = elGamalPK.encrypt(curve.getInfinity(), rndInt);
         ConcreteCrypto.ElGamalCiphertext originalEncodedCipher= ConcreteCrypto.ElGamalCiphertext.parseFrom(msg.getData());
 
-        Pair<ECPoint,ECPoint> originalCipher = new Pair<>(
+        Pair<ECPoint,ECPoint> originalCipher = new Pair<ECPoint, ECPoint>(
                 curve.decodePoint(originalEncodedCipher.getC1().toByteArray()),
                 curve.decodePoint(originalEncodedCipher.getC2().toByteArray()));
         Pair<ECPoint,ECPoint> newCipher = elGamalPK.add(originalCipher, randomizer);

settings.gradle

@@ -4,4 +4,5 @@ include 'bulletin-board-server'
 include 'polling-station'
 include 'restful-api-common'
 include 'bulletin-board-client'
+include 'destributed-key-generation'