/**
* @license
* Copyright 2016 Google Inc. All rights reserved.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.security.wycheproof;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;
import java.util.ArrayList;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.CipherOutputStream;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import junit.framework.TestCase;
/** CipherOutputStream tests */
public class CipherOutputStreamTest extends TestCase {
static final SecureRandom rand = new SecureRandom();
static byte[] randomBytes(int size) {
byte[] bytes = new byte[size];
rand.nextBytes(bytes);
return bytes;
}
static SecretKeySpec randomKey(String algorithm, int keySizeInBytes) {
return new SecretKeySpec(randomBytes(keySizeInBytes), "AES");
}
static AlgorithmParameterSpec randomParameters(
String algorithm, int ivSizeInBytes, int tagSizeInBytes) {
if ("AES/GCM/NoPadding".equals(algorithm) || "AES/EAX/NoPadding".equals(algorithm)) {
return new GCMParameterSpec(8 * tagSizeInBytes, randomBytes(ivSizeInBytes));
}
return null;
}
/** Test vectors */
@SuppressWarnings("InsecureCryptoUsage")
public static class TestVector {
public String algorithm;
public SecretKeySpec key;
public AlgorithmParameterSpec params;
public byte[] pt;
public byte[] aad;
public byte[] ct;
public TestVector(
String algorithm, int keySize, int ivSize, int tagSize, int ptSize, int aadSize)
throws Exception {
this.algorithm = algorithm;
this.key = randomKey(algorithm, keySize);
this.params = randomParameters(algorithm, ivSize, tagSize);
this.pt = randomBytes(ptSize);
this.aad = randomBytes(aadSize);
Cipher cipher = Cipher.getInstance(algorithm);
cipher.init(Cipher.ENCRYPT_MODE, this.key, this.params);
cipher.updateAAD(aad);
this.ct = cipher.doFinal(pt);
}
}
Iterable<TestVector> getTestVectors(
String algorithm,
int[] keySizes,
int[] ivSizes,
int[] tagSizes,
int[] ptSizes,
int[] aadSizes)
throws Exception {
ArrayList<TestVector> result = new ArrayList<TestVector>();
for (int keySize : keySizes) {
for (int ivSize : ivSizes) {
for (int tagSize : tagSizes) {
for (int ptSize : ptSizes) {
for (int aadSize : aadSizes) {
result.add(new TestVector(algorithm, keySize, ivSize, tagSize, ptSize, aadSize));
}
}
}
}
}
return result;
}
@SuppressWarnings("InsecureCryptoUsage")
public void testEncrypt(Iterable<TestVector> tests) throws Exception {
for (TestVector t : tests) {
Cipher cipher = Cipher.getInstance(t.algorithm);
cipher.init(Cipher.ENCRYPT_MODE, t.key, t.params);
cipher.updateAAD(t.aad);
ByteArrayOutputStream os = new ByteArrayOutputStream();
CipherOutputStream cos = new CipherOutputStream(os, cipher);
cos.write(t.pt);
cos.close();
assertEquals(TestUtil.bytesToHex(t.ct), TestUtil.bytesToHex(os.toByteArray()));
}
}
@SuppressWarnings("InsecureCryptoUsage")
public void testDecrypt(Iterable<TestVector> tests) throws Exception {
for (TestVector t : tests) {
Cipher cipher = Cipher.getInstance(t.algorithm);
cipher.init(Cipher.DECRYPT_MODE, t.key, t.params);
cipher.updateAAD(t.aad);
ByteArrayOutputStream os = new ByteArrayOutputStream();
CipherOutputStream cos = new CipherOutputStream(os, cipher);
cos.write(t.ct);
cos.close();
assertEquals(TestUtil.bytesToHex(t.pt), TestUtil.bytesToHex(os.toByteArray()));
}
}
@SuppressWarnings("InsecureCryptoUsage")
public void testCorruptDecrypt(Iterable<TestVector> tests) throws Exception {
for (TestVector t : tests) {
Cipher cipher = Cipher.getInstance(t.algorithm);
cipher.init(Cipher.DECRYPT_MODE, t.key, t.params);
cipher.updateAAD(t.aad);
byte[] ct = Arrays.copyOf(t.ct, t.ct.length);
ct[ct.length - 1] ^= (byte) 1;
ByteArrayOutputStream os = new ByteArrayOutputStream();
CipherOutputStream cos = new CipherOutputStream(os, cipher);
cos.write(ct);
try {
// cos.close() should call cipher.doFinal().
cos.close();
byte[] decrypted = os.toByteArray();
// Unfortunately Oracle thinks that returning an empty array is valid behaviour.
// We accept empty results here, but flag them in the next test, so that we can distinguish
// between beheviour considered acceptable by Oracle and more serious flaws.
if (decrypted.length > 0) {
fail(
"this should fail; decrypted:"
+ TestUtil.bytesToHex(decrypted)
+ " pt: "
+ TestUtil.bytesToHex(t.pt));
}
} catch (IOException ex) {
// expected
}
}
}
@SuppressWarnings("InsecureCryptoUsage")
public void testCorruptDecryptEmpty(Iterable<TestVector> tests) throws Exception {
for (TestVector t : tests) {
Cipher cipher = Cipher.getInstance(t.algorithm);
cipher.init(Cipher.DECRYPT_MODE, t.key, t.params);
cipher.updateAAD(t.aad);
byte[] ct = Arrays.copyOf(t.ct, t.ct.length);
ct[ct.length - 1] ^= (byte) 1;
ByteArrayOutputStream os = new ByteArrayOutputStream();
CipherOutputStream cos = new CipherOutputStream(os, cipher);
cos.write(ct);
try {
// cos.close() should call cipher.doFinal().
cos.close();
byte[] decrypted = os.toByteArray();
fail(
"this should fail; decrypted:"
+ TestUtil.bytesToHex(decrypted)
+ " pt: "
+ TestUtil.bytesToHex(t.pt));
} catch (IOException ex) {
// expected
}
}
}
public void testAesGcm() throws Exception {
final int[] keySizes = {16, 32};
final int[] ivSizes = {12};
final int[] tagSizes = {12, 16};
final int[] ptSizes = {8, 16, 65, 8100};
final int[] aadSizes = {0, 8, 24};
Iterable<TestVector> v =
getTestVectors("AES/GCM/NoPadding", keySizes, ivSizes, tagSizes, ptSizes, aadSizes);
testEncrypt(v);
testDecrypt(v);
testCorruptDecrypt(v);
}
/**
* Unfortunately Oracle thinks that returning an empty array is valid behaviour for corrupt
* ciphertexts. Because of this we test empty plaintext separately to distinguish behaviour
* considered acceptable by Oracle from other behaviour.
*/
public void testEmptyPlaintext() throws Exception {
final int[] keySizes = {16, 32};
final int[] ivSizes = {12};
final int[] tagSizes = {12, 16};
final int[] ptSizes = {0};
final int[] aadSizes = {0, 8, 24};
Iterable<TestVector> v =
getTestVectors("AES/GCM/NoPadding", keySizes, ivSizes, tagSizes, ptSizes, aadSizes);
testEncrypt(v);
testDecrypt(v);
testCorruptDecryptEmpty(v);
}
/** Tests CipherOutputStream with AES-EAX if AES-EAS is supported by the provider. */
@SuppressWarnings("InsecureCryptoUsage")
public void testAesEax() throws Exception {
final String algorithm = "AES/EAX/NoPadding";
final int[] keySizes = {16, 32};
final int[] ivSizes = {12, 16};
final int[] tagSizes = {12, 16};
final int[] ptSizes = {8, 16, 65, 8100};
final int[] aadSizes = {0, 8, 24};
try {
Cipher.getInstance(algorithm);
} catch (NoSuchAlgorithmException ex) {
System.out.println("Skipping testAesEax");
return;
}
Iterable<TestVector> v =
getTestVectors(algorithm, keySizes, ivSizes, tagSizes, ptSizes, aadSizes);
testEncrypt(v);
testDecrypt(v);
testCorruptDecrypt(v);
}
}