Create APIs: SecretShare, SplitSecret and SecretSplitter. Change split package to threshold

Author: gefeili

core/src/main/java/org/bouncycastle/crypto/threshold/SecretShare.java

@@ -0,0 +1,5 @@
+package org.bouncycastle.crypto.threshold;
+
+public interface SecretShare
+{
+}

…cycastle/crypto/split/SecretSharing.java …tle/crypto/threshold/SecretSplitter.javacore/src/main/java/org/bouncycastle/crypto/split/SecretSharing.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/SecretSplitter.java core/src/main/java/org/bouncycastle/crypto/split/SecretSharing.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/SecretSplitter.java

@@ -1,21 +1,18 @@
-package org.bouncycastle.crypto.split;
-
-import java.security.SecureRandom;
+package org.bouncycastle.crypto.threshold;
 
 /**
  * Secret sharing (also called secret splitting) refers to methods for distributing a secret among a group.
  * In this process, no individual holds any intelligible information about the secret.
  * However, when a sufficient number of individuals combine their 'shares', the secret can be reconstructed.
  */
-public interface SecretSharing
+public interface SecretSplitter
 {
     /**
      * Creates secret shares from a given secret. The secret will be divided into shares, where the secret has a length of L bytes.
      *
-     * @param random the source of secure random
      * @return An array of {@code byte[][]} representing the generated secret shares for m users with l bytes each.
      */
-    byte[][] createShares(SecureRandom random);
+    SplitSecret split();
 
     /**
      * Recombines secret shares to reconstruct the original secret.

…astle/crypto/split/PolynomialNative.java …hreshold/ShamirNativeSecretSplitter.javacore/src/main/java/org/bouncycastle/crypto/split/PolynomialNative.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirNativeSecretSplitter.java core/src/main/java/org/bouncycastle/crypto/split/PolynomialNative.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirNativeSecretSplitter.java

@@ -1,13 +1,15 @@
-package org.bouncycastle.crypto.split;
+package org.bouncycastle.crypto.threshold;
 
-public class PolynomialNative
-    extends Polynomial
+import java.security.SecureRandom;
+
+public class ShamirNativeSecretSplitter
+    extends ShamirSecretSplitter
 {
     private final int IRREDUCIBLE;
 
-    public PolynomialNative(int algorithm, int l, int m, int n)
+    public ShamirNativeSecretSplitter(int algorithm, int l, int m, int n, SecureRandom random)
     {
-        super(l, m, n);
+        super(l, m, n, random);
         switch (algorithm)
         {
         case AES:

…ouncycastle/crypto/split/Polynomial.java …ypto/threshold/ShamirSecretSplitter.javacore/src/main/java/org/bouncycastle/crypto/split/Polynomial.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirSecretSplitter.java core/src/main/java/org/bouncycastle/crypto/split/Polynomial.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirSecretSplitter.java

@@ -1,9 +1,9 @@
-package org.bouncycastle.crypto.split;
+package org.bouncycastle.crypto.threshold;
 
 import java.security.SecureRandom;
 
-public abstract class Polynomial
-    implements SecretSharing
+public abstract class ShamirSecretSplitter
+    implements SecretSplitter
 {
     public static final int AES = 0;
     public static final int RSA = 1;
@@ -21,8 +21,9 @@ public abstract class Polynomial
      */
     protected int n;
     protected byte[][] p;
+    protected SecureRandom random;
 
-    protected Polynomial(int l, int m, int n)
+    protected ShamirSecretSplitter(int l, int m, int n, SecureRandom random)
     {
         if (l < 0 || l > 65534)
         {
@@ -39,6 +40,7 @@ protected Polynomial(int l, int m, int n)
         this.l = l;
         this.m = m;
         this.n = n;
+        this.random = random;
     }
 
     protected void init()
@@ -53,20 +55,20 @@ protected void init()
         }
     }
 
-    public byte[][] createShares(SecureRandom random)
+    public ShamirSplitSecret split()
     {
         byte[][] sr = new byte[m][l];
-        byte[][] result = new byte[p.length][l];
+        ShamirSplitSecretShare[] secretShares = new ShamirSplitSecretShare[l];
         int i;
         for (i = 0; i < m; ++i)
         {
             random.nextBytes(sr[i]);
         }
         for (i = 0; i < p.length; i++)
         {
-            result[i] = gfVecMul(p[i], sr);
+            secretShares[i] = new ShamirSplitSecretShare(gfVecMul(p[i], sr), i + 1);
         }
-        return result;
+        return new ShamirSplitSecret(secretShares);
     }
 
     public byte[] recombineShares(int[] rr, byte[]... splits)

core/src/main/java/org/bouncycastle/crypto/threshold/ShamirSplitSecret.java

@@ -0,0 +1,17 @@
+package org.bouncycastle.crypto.threshold;
+
+public class ShamirSplitSecret
+    implements SplitSecret
+{
+    private ShamirSplitSecretShare[] secretShares;
+
+    public ShamirSplitSecret(ShamirSplitSecretShare[] secretShares)
+    {
+        this.secretShares = secretShares;
+    }
+
+    public ShamirSplitSecretShare[] getSecretShare()
+    {
+        return secretShares;
+    }
+}

core/src/main/java/org/bouncycastle/crypto/threshold/ShamirSplitSecretShare.java

@@ -0,0 +1,21 @@
+package org.bouncycastle.crypto.threshold;
+
+import org.bouncycastle.util.Arrays;
+
+public class ShamirSplitSecretShare
+    implements SecretShare
+{
+    private final byte[] secretShare;
+    private final int r; // index of secretShare
+
+    public ShamirSplitSecretShare(byte[] secretShare, int r)
+    {
+        this.secretShare = Arrays.clone(secretShare);
+        this.r = r;
+    }
+
+    public byte[] getSecretShare()
+    {
+        return secretShare;
+    }
+}

…castle/crypto/split/PolynomialTable.java …threshold/ShamirTableSecretSplitter.javacore/src/main/java/org/bouncycastle/crypto/split/PolynomialTable.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirTableSecretSplitter.java core/src/main/java/org/bouncycastle/crypto/split/PolynomialTable.java renamed to core/src/main/java/org/bouncycastle/crypto/threshold/ShamirTableSecretSplitter.java

@@ -1,7 +1,9 @@
-package org.bouncycastle.crypto.split;
+package org.bouncycastle.crypto.threshold;
 
-public class PolynomialTable
-    extends Polynomial
+import java.security.SecureRandom;
+
+public class ShamirTableSecretSplitter
+    extends ShamirSecretSplitter
 {
     private final byte[] LOG;
     private final byte[] EXP;
@@ -146,9 +148,9 @@ public class PolynomialTable
         (byte)0x1b, (byte)0x36, (byte)0x6c, (byte)0xd8, (byte)0xad, (byte)0x47, (byte)0x8e, (byte)0x01
     };
 
-    public PolynomialTable(int algorithm, int l, int m, int n)
+    public ShamirTableSecretSplitter(int algorithm, int l, int m, int n, SecureRandom random)
     {
-        super(l, m, n);
+        super(l, m, n, random);
         switch (algorithm)
         {
         case AES:

core/src/main/java/org/bouncycastle/crypto/threshold/SplitSecret.java

@@ -0,0 +1,6 @@
+package org.bouncycastle.crypto.threshold;
+
+public interface SplitSecret
+{
+    SecretShare[] getSecretShare();
+}

…cycastle/crypto/split/test/AllTests.java …stle/crypto/threshold/test/AllTests.javacore/src/test/java/org/bouncycastle/crypto/split/test/AllTests.java renamed to core/src/test/java/org/bouncycastle/crypto/threshold/test/AllTests.java core/src/test/java/org/bouncycastle/crypto/split/test/AllTests.java renamed to core/src/test/java/org/bouncycastle/crypto/threshold/test/AllTests.java

@@ -1,4 +1,4 @@
-package org.bouncycastle.crypto.split.test;
+package org.bouncycastle.crypto.threshold.test;
 
 import junit.extensions.TestSetup;
 import junit.framework.Test;
@@ -18,7 +18,7 @@ public static void main(String[] args)
     public static Test suite()
     {
         TestSuite suite = new TestSuite("Secret Sharing Tests");
-        suite.addTestSuite(PolynomialTest.class);
+        suite.addTestSuite(ShamirSecretSplitterTest.class);
         return new AllTests.BCTestSetup(suite);
     }