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Switch to using dedicated artifact for Shamir's secret sharing implementation.

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This commit is contained in:
Marko Zivanovic
2014-12-01 19:51:11 +01:00
parent 9fb439a326
commit f44ba85331
8 changed files with 36 additions and 579 deletions
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pom.xml
+18 -2
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@@ -40,6 +40,11 @@
<version>4.10</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>rs.in.zivanovic</groupId>
<artifactId>sss</artifactId>
<version>1.0.0</version>
</dependency>
</dependencies>
<build>
@@ -47,7 +52,7 @@
<plugin>
<groupId>com.github.wvengen</groupId>
<artifactId>proguard-maven-plugin</artifactId>
<version>2.0.6</version>
<version>2.0.8</version>
<executions>
<execution>
<phase>package</phase>
@@ -69,7 +74,7 @@
<dependency>
<groupId>net.sf.proguard</groupId>
<artifactId>proguard-base</artifactId>
<version>4.9</version>
<version>5.1</version>
</dependency>
</dependencies>
</plugin>
@@ -87,5 +92,16 @@
</configuration>
</plugin>
</plugins>
<resources>
<resource>
<directory>src/main/resources</directory>
<filtering>false</filtering>
</resource>
<resource>
<directory>src/main/resources-filtered</directory>
<filtering>true</filtering>
</resource>
</resources>
</build>
</project>
src/main/java/rs/in/zivanovic/share/a/secret/Main.java
+16 -4
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@@ -1,5 +1,5 @@
/*
* Copyright (c) 2014, Marko Živanović
* Copyright (c) 2014, Marko Zivanovic
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
@@ -30,6 +30,11 @@ import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import rs.in.zivanovic.sss.SasUtils;
import rs.in.zivanovic.sss.SecretShare;
import rs.in.zivanovic.sss.ShamirSecretSharing;
/**
* Entry point into application.
@@ -59,7 +64,7 @@ public class Main {
try {
int s = line.indexOf("U1");
if (s >= 0) {
SecretShare share = Utils.decodeFromBinary(Base64.decode(line.substring(s)));
SecretShare share = SasUtils.decodeFromBinary(Base64.decode(line.substring(s)));
shares.add(share);
} else {
System.err.println("Invalid data");
@@ -83,7 +88,7 @@ public class Main {
String line = br.readLine();
List<SecretShare> shares = ShamirSecretSharing.split(line, totalShares, thresholdShares);
for (SecretShare share : shares) {
System.out.println(Base64.encodeBytes(Utils.encodeToBinary(share)));
System.out.println(Base64.encodeBytes(SasUtils.encodeToBinary(share)));
System.out.println();
}
} catch (IOException ex) {
@@ -92,7 +97,14 @@ public class Main {
}
private static void showHelp() {
System.err.println("Share-A-Secret 1.0.0-SNAPSHOT");
String version = "Share-A-Secret <unknown version>";
try {
ResourceBundle rb = ResourceBundle.getBundle("version");
version = String.format("%s %s", rb.getString("app.name"), rb.getString("app.version"));
} catch (MissingResourceException unused) {
// use default value
}
System.err.println(version);
System.err.println("This application uses Shamir's secret sharing algorithm to split the secret data into");
System.err.println("a desired number of shares. In order to retrieve the secret data, at least a required");
System.err.println("minimum number of shares must be present.");
src/main/java/rs/in/zivanovic/share/a/secret/SecretShare.java
-94
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@@ -1,94 +0,0 @@
/*
* Copyright (c) 2014, Marko Živanović
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package rs.in.zivanovic.share.a.secret;
import java.math.BigInteger;
import java.util.Objects;
/**
*
* @author marko
*/
public final class SecretShare {
private final int n;
private final BigInteger share;
private final BigInteger prime;
public SecretShare(int n, BigInteger share, BigInteger prime) {
this.n = n;
this.share = share;
this.prime = prime;
}
public int getN() {
return n;
}
public BigInteger getShare() {
return share;
}
public BigInteger getPrime() {
return prime;
}
@Override
public int hashCode() {
int hash = 7;
hash = 79 * hash + this.n;
hash = 79 * hash + Objects.hashCode(this.share);
hash = 79 * hash + Objects.hashCode(this.prime);
return hash;
}
@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
final SecretShare other = (SecretShare) obj;
if (this.n != other.n) {
return false;
}
if (!Objects.equals(this.share, other.share)) {
return false;
}
if (!Objects.equals(this.prime, other.prime)) {
return false;
}
return true;
}
@Override
public String toString() {
return "SecretShare{" + "n=" + n + ", share=" + share + ", prime=" + prime + '}';
}
}
src/main/java/rs/in/zivanovic/share/a/secret/ShamirSecretSharing.java
-126
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@@ -1,126 +0,0 @@
/*
* Copyright (c) 2014, Marko Živanović
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package rs.in.zivanovic.share.a.secret;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.List;
/**
*
* @author marko
*/
public final class ShamirSecretSharing {
public static List<SecretShare> split(String secretString, int total, int threshold) {
BigInteger secret = Utils.encodeSecret(secretString);
return split(secret, total, threshold);
}
public static List<SecretShare> split(BigInteger secretNumber, int total, int threshold) {
BigInteger prime = Utils.getFirstPrimeGreaterThan(secretNumber);
BigInteger[] coeffs = Utils.generateRandomCoefficients(total, secretNumber, prime);
return split(secretNumber, coeffs, total, threshold, prime);
}
public static List<SecretShare> split(BigInteger secret, BigInteger[] coefficients, int total, int threshold,
BigInteger prime) {
if (secret.compareTo(BigInteger.ZERO) <= 0) {
throw new IllegalArgumentException("Secret must be positive integer");
}
if (prime.compareTo(secret) <= 0) {
throw new IllegalArgumentException("Prime must be greater than secret");
}
if (coefficients.length < threshold) {
throw new IllegalArgumentException("Not enough coefficients, need " + threshold + ", has " +
coefficients.length);
}
if (total < threshold) {
throw new IllegalArgumentException("Total number of shares must be greater than or equal threshold");
}
List<SecretShare> shares = new ArrayList<>();
for (int i = 1; i <= total; i++) {
BigInteger x = BigInteger.valueOf(i);
BigInteger v = coefficients[0];
for (int c = 1; c < threshold; c++) {
v = v.add(x.modPow(BigInteger.valueOf(c), prime).multiply(coefficients[c]).mod(prime)).mod(prime);
}
shares.add(new SecretShare(i, v, prime));
}
return shares;
}
public static String joinToUtf8String(List<SecretShare> shares) {
return Utils.decodeSecret(join(shares));
}
public static BigInteger join(List<SecretShare> shares) {
if (!checkSamePrimes(shares)) {
throw new IllegalArgumentException("Shares not from the same series");
}
BigInteger res = BigInteger.ZERO;
for (int i = 0; i < shares.size(); i++) {
BigInteger n = BigInteger.ONE;
BigInteger d = BigInteger.ONE;
BigInteger prime = shares.get(i).getPrime();
for (int j = 0; j < shares.size(); j++) {
if (i != j) {
BigInteger sp = BigInteger.valueOf(shares.get(i).getN());
BigInteger np = BigInteger.valueOf(shares.get(j).getN());
n = n.multiply(np.negate()).mod(prime);
d = d.multiply(sp.subtract(np)).mod(prime);
}
}
BigInteger v = shares.get(i).getShare();
res = res.add(prime).add(v.multiply(n).multiply(d.modInverse(prime))).mod(prime);
}
return res;
}
private static boolean checkSamePrimes(List<SecretShare> shares) {
boolean ret = true;
BigInteger prime = null;
for (SecretShare share : shares) {
if (prime == null) {
prime = share.getPrime();
} else if (!prime.equals(share.getPrime())) {
ret = false;
break;
}
}
return ret;
}
private ShamirSecretSharing() {
}
}
src/main/java/rs/in/zivanovic/share/a/secret/Utils.java
-148
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@@ -1,148 +0,0 @@
/*
* Copyright (c) 2014, Marko Živanović
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package rs.in.zivanovic.share.a.secret;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.SecureRandom;
import java.util.Arrays;
import java.util.Random;
/**
*
* @author marko
*/
public final class Utils {
private static final Random RANDOM = new SecureRandom();
private static final byte[] SIGNATURE = "SS".getBytes(StandardCharsets.UTF_8);
public static BigInteger encodeSecret(String secret) {
byte[] bytes = secret.getBytes(StandardCharsets.UTF_8);
byte[] res;
if ((bytes[0] & 0b10000000) >> 7 == 1) {
res = new byte[bytes.length + 1];
res[0] = 0;
System.arraycopy(bytes, 0, res, 1, bytes.length);
} else {
res = bytes;
}
BigInteger r = new BigInteger(res);
assert r.compareTo(BigInteger.ZERO) > 0;
return r;
}
@SuppressWarnings("empty-statement")
public static String decodeSecret(BigInteger secret) {
byte[] bytes = secret.toByteArray();
int count;
for (count = 0; count < bytes.length && bytes[count] == 0; count++);
byte[] trimmed = new byte[bytes.length - count];
System.arraycopy(bytes, count, trimmed, 0, trimmed.length);
return new String(trimmed, StandardCharsets.UTF_8);
}
public static BigInteger getFirstPrimeGreaterThan(BigInteger secret) {
return secret.nextProbablePrime();
}
public static BigInteger getRandomPrimeGreaterThan(BigInteger prime) {
BigInteger res = BigInteger.ZERO;
while (res.compareTo(prime) <= 0) {
res = BigInteger.probablePrime(prime.bitLength(), RANDOM);
}
return res;
}
public static BigInteger getRandomLessThan(BigInteger prime) {
BigInteger r = null;
while (r == null || r.compareTo(prime) >= 0) {
r = new BigInteger(prime.bitLength(), RANDOM);
}
return r;
}
public static BigInteger[] generateRandomCoefficients(int n, BigInteger elementZero, BigInteger prime) {
BigInteger[] res = new BigInteger[n];
res[0] = elementZero;
for (int i = 1; i < n; i++) {
res[i] = Utils.getRandomLessThan(prime);
}
return res;
}
public static byte[] encodeToBinary(SecretShare share) {
assert share.getN() >= 0;
assert share.getN() <= 255;
byte[] shareData = share.getShare().toByteArray();
byte[] primeData = share.getPrime().toByteArray();
byte n = new Integer(share.getN()).byteValue();
int len = 9 + SIGNATURE.length + shareData.length + primeData.length;
ByteBuffer bb = ByteBuffer.allocate(len);
bb.put(SIGNATURE);
bb.put(n);
bb.putInt(shareData.length);
bb.put(shareData);
bb.putInt(primeData.length);
bb.put(primeData);
assert bb.position() == bb.capacity();
assert bb.hasArray();
return bb.array();
}
public static SecretShare decodeFromBinary(byte[] data) {
ByteBuffer bb = ByteBuffer.wrap(data);
byte[] signature = new byte[SIGNATURE.length];
bb.get(signature);
if (!Arrays.equals(SIGNATURE, signature)) {
throw new IllegalArgumentException("Invalid data");
}
byte n = bb.get();
int shareDataLen = bb.getInt();
byte[] shareData = new byte[shareDataLen];
bb.get(shareData);
int primeDataLen = bb.getInt();
byte[] primeData = new byte[primeDataLen];
bb.get(primeData);
assert bb.position() == bb.capacity();
BigInteger share = new BigInteger(shareData);
BigInteger prime = new BigInteger(primeData);
assert share.compareTo(BigInteger.ZERO) > 0;
assert prime.compareTo(BigInteger.ZERO) > 0;
return new SecretShare(n, share, prime);
}
private Utils() {
}
}
src/main/resources-filtered/version.properties
+2
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@@ -0,0 +1,2 @@
app.name=${project.name}
app.version=${project.version}
src/test/java/rs/in/zivanovic/share/a/secret/ShamirSecretSharingTest.java
-109
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@@ -1,109 +0,0 @@
/*
* Copyright (c) 2014, Marko Živanović
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package rs.in.zivanovic.share.a.secret;
import java.math.BigInteger;
import java.util.*;
import static org.junit.Assert.*;
import org.junit.Test;
/**
*
* @author marko
*/
public class ShamirSecretSharingTest {
private static final BigInteger[] TEST_COEFFICIENTS = new BigInteger[3];
private static final BigInteger TEST_PRIME = BigInteger.valueOf(1613);
private static final BigInteger TEST_SECRET = BigInteger.valueOf(1234);
private static final List<SecretShare> SHARES;
static {
TEST_COEFFICIENTS[0] = TEST_SECRET;
TEST_COEFFICIENTS[1] = BigInteger.valueOf(166);
TEST_COEFFICIENTS[2] = BigInteger.valueOf(94);
SHARES = ShamirSecretSharing.split(TEST_SECRET, TEST_COEFFICIENTS, 6, 3, TEST_PRIME);
}
@Test
public void testSplit() {
System.out.println("split");
assertTrue(SHARES.get(0).getShare().compareTo(BigInteger.valueOf(1494)) == 0);
assertTrue(SHARES.get(1).getShare().compareTo(BigInteger.valueOf(329)) == 0);
assertTrue(SHARES.get(2).getShare().compareTo(BigInteger.valueOf(965)) == 0);
assertTrue(SHARES.get(3).getShare().compareTo(BigInteger.valueOf(176)) == 0);
assertTrue(SHARES.get(4).getShare().compareTo(BigInteger.valueOf(1188)) == 0);
assertTrue(SHARES.get(5).getShare().compareTo(BigInteger.valueOf(775)) == 0);
}
@Test
public void testJoinInsufficientShares() {
System.out.println("joinInsufficientShares");
List<SecretShare> shares = new ArrayList<>();
shares.add(SHARES.get(0));
shares.add(SHARES.get(5));
BigInteger joined = ShamirSecretSharing.join(shares);
assertTrue(joined.compareTo(TEST_SECRET) != 0);
}
@Test
public void testJoinSufficientShares() {
System.out.println("joinSufficientShares");
List<SecretShare> shares = new ArrayList<>();
shares.add(SHARES.get(3));
shares.add(SHARES.get(5));
shares.add(SHARES.get(1));
BigInteger joined = ShamirSecretSharing.join(shares);
assertTrue(joined.compareTo(TEST_SECRET) == 0);
}
@Test
public void testLongStrings() {
System.out.println("longStrings");
String s = "Quick brown fox jumps over the lazy dog.";
test(s, 6, 5);
s = "Текст на ћирилици, чучко, џеки, Ђорђе, ...";
test(s, 6, 5);
s = "A sada da vidimo istu duzinu, ali, obican ";
test(s, 6, 5);
s = "ATTACK AT DAWN";
test(s, 6, 5);
}
private void test(String s, int total, int required) {
List<SecretShare> shares = ShamirSecretSharing.split(s, total, required);
List<SecretShare> someShares = new ArrayList<>();
for (int i = required - 1; i >= 0; i--) {
someShares.add(shares.get(i));
}
String joined = ShamirSecretSharing.joinToUtf8String(someShares);
assertTrue(joined.equals(s));
}
}
src/test/java/rs/in/zivanovic/share/a/secret/UtilsTest.java
-96
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@@ -1,96 +0,0 @@
/*
* Copyright (c) 2014, Marko Živanović
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package rs.in.zivanovic.share.a.secret;
import java.math.BigInteger;
import static org.junit.Assert.*;
import org.junit.Test;
/**
*
* @author marko
*/
public class UtilsTest {
private static final String s1 = "Hello World!";
private static final String s2 = "The quick brown fox jumps over the lazy dog.";
private static final String s3 = "Текст на ћирилици.";
public UtilsTest() {
}
@Test
public void testGetFirstPrimeGreaterThan() {
System.out.println("getFirstPrimeGreaterThan");
BigInteger si1 = Utils.encodeSecret(s1);
BigInteger si2 = Utils.encodeSecret(s2);
BigInteger p1 = Utils.getFirstPrimeGreaterThan(si1);
BigInteger p2 = Utils.getFirstPrimeGreaterThan(si2);
assertTrue(p1.compareTo(si1) > 0);
assertTrue(p2.compareTo(si2) > 0);
}
@Test
public void testGetRandomPrimeGreaterThan() {
System.out.println("getRandomPrimeGreaterThan");
BigInteger si1 = Utils.encodeSecret(s1);
BigInteger si2 = Utils.encodeSecret(s2);
BigInteger p1 = Utils.getRandomPrimeGreaterThan(si1);
BigInteger p2 = Utils.getRandomPrimeGreaterThan(si2);
assertTrue(p1.compareTo(si1) > 0);
assertTrue(p2.compareTo(si2) > 0);
}
@Test
public void testGetRandomLessThan() {
System.out.println("getRandomLessThan");
BigInteger i = BigInteger.valueOf(100);
BigInteger r = Utils.getRandomLessThan(i);
assertTrue(r.compareTo(i) < 0);
i = BigInteger.valueOf(100_000_000);
r = Utils.getRandomLessThan(i);
assertTrue(r.compareTo(i) < 0);
}
@Test
public void testBinaryCodec() {
System.out.println("binaryCodec");
SecretShare src = new SecretShare(3, new BigInteger("100"), new BigInteger("200"));
byte[] data = Utils.encodeToBinary(src);
SecretShare dst = Utils.decodeFromBinary(data);
assertTrue(src.equals(dst));
}
@Test
public void testSecretCodec() {
System.out.println("secretCodec");
String s = "Текст на ћирилици, чучко, џеки, Ђорђе, ...";
BigInteger bi = Utils.encodeSecret(s);
String d = Utils.decodeSecret(bi);
assertTrue(s.equals(d));
}
}