java_src/src/test/java/com/google/crypto/tink/aead/internal/InsecureNonceChaCha20Poly1305Test.java - third_party/tink - Git at Google

 // Copyright 2021 Google LLC
 //
 // 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.crypto.tink.aead.internal;

 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThrows;

 import com.google.crypto.tink.config.TinkFips;
 import com.google.crypto.tink.subtle.Bytes;
 import com.google.crypto.tink.subtle.Hex;
 import com.google.crypto.tink.subtle.Random;
 import com.google.crypto.tink.testing.TestUtil;
 import com.google.crypto.tink.testing.TestUtil.BytesMutation;
 import com.google.crypto.tink.testing.WycheproofTestUtil;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
 import java.security.GeneralSecurityException;
 import java.security.InvalidKeyException;
 import java.util.Arrays;
 import java.util.HashSet;
 import javax.crypto.AEADBadTagException;
 import org.junit.Assume;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

 /** Unit tests for {@link InsecureNonceChaCha20Poly1305}. */
 @RunWith(JUnit4.class)
 public class InsecureNonceChaCha20Poly1305Test {
   private static final int KEY_SIZE_IN_BYTES = 32;
   private static final int NONCE_SIZE_IN_BYTES = 12;
   private static final int TAG_SIZE_IN_BYTES = 16;

   public InsecureNonceChaCha20Poly1305 createInstance(final byte[] key)
       throws GeneralSecurityException {
     return new InsecureNonceChaCha20Poly1305(key);
   }

   @Test
   public void testSnufflePoly1305ThrowsInvalidAlgorithmParameterExpWhenKeyLenIsGreaterThan32()
       throws InvalidKeyException {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     InvalidKeyException e =
         assertThrows(
             InvalidKeyException.class,
             () -> createInstance(new byte[KEY_SIZE_IN_BYTES + 1]));
     assertThat(e).hasMessageThat().containsMatch("The key length in bytes must be 32.");
   }

   @Test
   public void testSnufflePoly1305ThrowsInvalidAlgorithmParameterExpWhenKeyLenIsLessThan32()
       throws InvalidKeyException {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     InvalidKeyException e =
         assertThrows(
             InvalidKeyException.class, () -> createInstance(new byte[KEY_SIZE_IN_BYTES - 1]));
     assertThat(e).hasMessageThat().containsMatch("The key length in bytes must be 32.");
   }

   @Test
   public void testDecryptThrowsGeneralSecurityExpWhenCiphertextIsTooShort()
       throws GeneralSecurityException {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     InsecureNonceChaCha20Poly1305 cipher =
         createInstance(new byte[KEY_SIZE_IN_BYTES]);
     GeneralSecurityException e =
         assertThrows(
             GeneralSecurityException.class,
             () ->
                 cipher.decrypt(
                     new byte[NONCE_SIZE_IN_BYTES], new byte[TAG_SIZE_IN_BYTES - 1], new byte[1]));
     assertThat(e).hasMessageThat().containsMatch("ciphertext too short");
   }

   @Test
   public void testEncryptDecrypt() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     InsecureNonceChaCha20Poly1305 cipher =
         createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
     for (int i = 0; i < 100; i++) {
       byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
       byte[] message = Random.randBytes(i);
       byte[] aad = Random.randBytes(i);
       byte[] ciphertext = cipher.encrypt(nonce, message, aad);
       byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
       assertArrayEquals(message, decrypted);
     }
   }

   /** BC had a bug, where GCM failed for messages of size > 8192 */
   @Test
   public void testLongMessages() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());
     Assume.assumeFalse(TestUtil.isAndroid()); // Doesn't work on Android

     int dataSize = 16;
     while (dataSize <= (1 << 24)) {
       byte[] plaintext = Random.randBytes(dataSize);
       byte[] aad = Random.randBytes(dataSize / 3);
       byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
       byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
       InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
       byte[] ciphertext = cipher.encrypt(nonce, plaintext, aad);
       byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
       assertArrayEquals(plaintext, decrypted);
       dataSize += 5 * dataSize / 11;
     }
   }

   @Test
   public void testModifyCiphertext() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
     InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
     byte[] aad = Random.randBytes(16);
     byte[] message = Random.randBytes(32);
     byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
     byte[] ciphertext = cipher.encrypt(nonce, message, aad);

     for (BytesMutation mutation : TestUtil.generateMutations(ciphertext)) {
       assertThrows(
           String.format(
               "Decrypting modified ciphertext should fail : ciphertext = %s, aad = %s,"
                   + " description = %s",
               Hex.encode(mutation.value), Arrays.toString(aad), mutation.description),
           GeneralSecurityException.class,
           () -> {
             byte[] unused = cipher.decrypt(nonce, mutation.value, aad);
           });
     }

     // Modify AAD
     for (int b = 0; b < aad.length; b++) {
       for (int bit = 0; bit < 8; bit++) {
         byte[] modified = Arrays.copyOf(aad, aad.length);
         modified[b] ^= (byte) (1 << bit);
         assertThrows(
             AEADBadTagException.class,
             () -> {
               byte[] unused = cipher.decrypt(nonce, ciphertext, modified);
             });
       }
     }
   }

   @Test
   public void testNullPlaintextOrCiphertext() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     InsecureNonceChaCha20Poly1305 cipher =
         createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
     byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
     byte[] aad = new byte[] {1, 2, 3};
     assertThrows(
         NullPointerException.class,
         () -> {
           byte[] unused = cipher.encrypt(nonce, null, aad);
         });
     assertThrows(
         NullPointerException.class,
         () -> {
           byte[] unused = cipher.encrypt(nonce, null, null);
         });
     assertThrows(
         NullPointerException.class,
         () -> {
           byte[] unused = cipher.decrypt(nonce, null, aad);
         });
     assertThrows(
         NullPointerException.class,
         () -> {
           byte[] unused = cipher.decrypt(nonce, null, null);
         });
   }

   @Test
   public void testEmptyAssociatedData() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     byte[] aad = new byte[0];
     InsecureNonceChaCha20Poly1305 cipher =
         createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
     byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
     for (int messageSize = 0; messageSize < 75; messageSize++) {
       byte[] message = Random.randBytes(messageSize);
       { // encrypting with aad as a 0-length array
         byte[] ciphertext = cipher.encrypt(nonce, message, aad);
         byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
         assertArrayEquals(message, decrypted);
         byte[] decrypted2 = cipher.decrypt(nonce, ciphertext, null);
         assertArrayEquals(message, decrypted2);
         byte[] badAad = new byte[] {1, 2, 3};
         assertThrows(
             AEADBadTagException.class,
             () -> {
               byte[] unused = cipher.decrypt(nonce, ciphertext, badAad);
             });
       }
       { // encrypting with aad equal to null
         byte[] ciphertext = cipher.encrypt(nonce, message, null);
         byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
         assertArrayEquals(message, decrypted);
         byte[] decrypted2 = cipher.decrypt(nonce, ciphertext, null);
         assertArrayEquals(message, decrypted2);
         byte[] badAad = new byte[] {1, 2, 3};
         assertThrows(
             AEADBadTagException.class,
             () -> {
               byte[] unused = cipher.decrypt(nonce, ciphertext, badAad);
             });
       }
     }
   }

   /**
    * This test simply checks that multiple ciphertexts of the same message with a different nonce
    * are distinct.
    */
   @Test
   public void testNonce() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
     InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
     byte[] message = new byte[0];
     byte[] aad = new byte[0];
     HashSet<String> ciphertexts = new HashSet<>();
     final int samples = 1 << 10;
     for (int i = 0; i < samples; i++) {
       byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
       byte[] ct = cipher.encrypt(nonce, message, aad);
       String ctHex = TestUtil.hexEncode(ct);
       assertThat(ciphertexts).doesNotContain(ctHex);
       ciphertexts.add(ctHex);
     }
     assertThat(ciphertexts).hasSize(samples);
   }

   @Test
   public void testWycheproofVectors() throws Exception {
     Assume.assumeFalse(TinkFips.useOnlyFips());

     JsonObject json =
         WycheproofTestUtil.readJson(
             "../wycheproof/testvectors/chacha20_poly1305_test.json");
     int errors = 0;
     JsonArray testGroups = json.getAsJsonArray("testGroups");
     for (int i = 0; i < testGroups.size(); i++) {
       JsonObject group = testGroups.get(i).getAsJsonObject();
       JsonArray tests = group.getAsJsonArray("tests");
       for (int j = 0; j < tests.size(); j++) {
         JsonObject testcase = tests.get(j).getAsJsonObject();
         String tcId =
             String.format(
                 "testcase %d (%s)",
                 testcase.get("tcId").getAsInt(), testcase.get("comment").getAsString());
         byte[] iv = Hex.decode(testcase.get("iv").getAsString());
         byte[] key = Hex.decode(testcase.get("key").getAsString());
         byte[] msg = Hex.decode(testcase.get("msg").getAsString());
         byte[] aad = Hex.decode(testcase.get("aad").getAsString());
         byte[] ct = Hex.decode(testcase.get("ct").getAsString());
         byte[] tag = Hex.decode(testcase.get("tag").getAsString());
         byte[] ciphertext = Bytes.concat(ct, tag);
         // Result is one of "valid", "invalid", "acceptable".
         // "valid" are test vectors with matching plaintext, ciphertext and tag.
         // "invalid" are test vectors with invalid parameters or invalid ciphertext and tag.
         // "acceptable" are test vectors with weak parameters or legacy formats.
         String result = testcase.get("result").getAsString();
         try {
           InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
           // Encryption.
           byte[] encrypted = cipher.encrypt(iv, msg, aad);
           boolean ciphertextMatches = TestUtil.arrayEquals(encrypted, ciphertext);
           if (result.equals("valid") && !ciphertextMatches) {
             System.err.printf(
                 "FAIL %s: incorrect encryption, result: %s, expected: %s%n",
                 tcId, Hex.encode(encrypted), Hex.encode(ciphertext));
             errors++;
           }
           // Decryption.
           byte[] decrypted = cipher.decrypt(iv, ciphertext, aad);
           boolean plaintextMatches = TestUtil.arrayEquals(decrypted, msg);
           if (result.equals("invalid")) {
             System.out.printf(
                 "FAIL %s: accepting invalid ciphertext, cleartext: %s, decrypted: %s%n",
                 tcId, Hex.encode(msg), Hex.encode(decrypted));
             errors++;
           } else {
             if (!plaintextMatches) {
               System.out.printf(
                   "FAIL %s: incorrect decryption, result: %s, expected: %s%n",
                   tcId, Hex.encode(decrypted), Hex.encode(msg));
               errors++;
             }
           }
         } catch (GeneralSecurityException ex) {
           if (result.equals("valid")) {
             System.out.printf("FAIL %s: cannot decrypt, exception %s%n", tcId, ex);
             errors++;
           }
         }
       }
     }
     assertEquals(0, errors);
   }

   @Test
   public void testFailIfFipsModuleNotAvailable() throws Exception {
     Assume.assumeTrue(TinkFips.useOnlyFips());

     byte[] key = Random.randBytes(32);
     assertThrows(
         GeneralSecurityException.class,
         () -> new InsecureNonceChaCha20Poly1305(key));
   }
 }
	// Copyright 2021 Google LLC
	//
	// 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.crypto.tink.aead.internal;

	import static com.google.common.truth.Truth.assertThat;
	import static org.junit.Assert.assertArrayEquals;
	import static org.junit.Assert.assertEquals;
	import static org.junit.Assert.assertThrows;

	import com.google.crypto.tink.config.TinkFips;
	import com.google.crypto.tink.subtle.Bytes;
	import com.google.crypto.tink.subtle.Hex;
	import com.google.crypto.tink.subtle.Random;
	import com.google.crypto.tink.testing.TestUtil;
	import com.google.crypto.tink.testing.TestUtil.BytesMutation;
	import com.google.crypto.tink.testing.WycheproofTestUtil;
	import com.google.gson.JsonArray;
	import com.google.gson.JsonObject;
	import java.security.GeneralSecurityException;
	import java.security.InvalidKeyException;
	import java.util.Arrays;
	import java.util.HashSet;
	import javax.crypto.AEADBadTagException;
	import org.junit.Assume;
	import org.junit.Test;
	import org.junit.runner.RunWith;
	import org.junit.runners.JUnit4;

	/** Unit tests for {@link InsecureNonceChaCha20Poly1305}. */
	@RunWith(JUnit4.class)
	public class InsecureNonceChaCha20Poly1305Test {
	private static final int KEY_SIZE_IN_BYTES = 32;
	private static final int NONCE_SIZE_IN_BYTES = 12;
	private static final int TAG_SIZE_IN_BYTES = 16;

	public InsecureNonceChaCha20Poly1305 createInstance(final byte[] key)
	throws GeneralSecurityException {
	return new InsecureNonceChaCha20Poly1305(key);
	}

	@Test
	public void testSnufflePoly1305ThrowsInvalidAlgorithmParameterExpWhenKeyLenIsGreaterThan32()
	throws InvalidKeyException {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	InvalidKeyException e =
	assertThrows(
	InvalidKeyException.class,
	() -> createInstance(new byte[KEY_SIZE_IN_BYTES + 1]));
	assertThat(e).hasMessageThat().containsMatch("The key length in bytes must be 32.");
	}

	@Test
	public void testSnufflePoly1305ThrowsInvalidAlgorithmParameterExpWhenKeyLenIsLessThan32()
	throws InvalidKeyException {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	InvalidKeyException e =
	assertThrows(
	InvalidKeyException.class, () -> createInstance(new byte[KEY_SIZE_IN_BYTES - 1]));
	assertThat(e).hasMessageThat().containsMatch("The key length in bytes must be 32.");
	}

	@Test
	public void testDecryptThrowsGeneralSecurityExpWhenCiphertextIsTooShort()
	throws GeneralSecurityException {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	InsecureNonceChaCha20Poly1305 cipher =
	createInstance(new byte[KEY_SIZE_IN_BYTES]);
	GeneralSecurityException e =
	assertThrows(
	GeneralSecurityException.class,
	() ->
	cipher.decrypt(
	new byte[NONCE_SIZE_IN_BYTES], new byte[TAG_SIZE_IN_BYTES - 1], new byte[1]));
	assertThat(e).hasMessageThat().containsMatch("ciphertext too short");
	}

	@Test
	public void testEncryptDecrypt() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	InsecureNonceChaCha20Poly1305 cipher =
	createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
	for (int i = 0; i < 100; i++) {
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	byte[] message = Random.randBytes(i);
	byte[] aad = Random.randBytes(i);
	byte[] ciphertext = cipher.encrypt(nonce, message, aad);
	byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
	assertArrayEquals(message, decrypted);
	}
	}

	/** BC had a bug, where GCM failed for messages of size > 8192 */
	@Test
	public void testLongMessages() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());
	Assume.assumeFalse(TestUtil.isAndroid()); // Doesn't work on Android

	int dataSize = 16;
	while (dataSize <= (1 << 24)) {
	byte[] plaintext = Random.randBytes(dataSize);
	byte[] aad = Random.randBytes(dataSize / 3);
	byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
	byte[] ciphertext = cipher.encrypt(nonce, plaintext, aad);
	byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
	assertArrayEquals(plaintext, decrypted);
	dataSize += 5 * dataSize / 11;
	}
	}

	@Test
	public void testModifyCiphertext() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
	InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
	byte[] aad = Random.randBytes(16);
	byte[] message = Random.randBytes(32);
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	byte[] ciphertext = cipher.encrypt(nonce, message, aad);

	for (BytesMutation mutation : TestUtil.generateMutations(ciphertext)) {
	assertThrows(
	String.format(
	"Decrypting modified ciphertext should fail : ciphertext = %s, aad = %s,"
	+ " description = %s",
	Hex.encode(mutation.value), Arrays.toString(aad), mutation.description),
	GeneralSecurityException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, mutation.value, aad);
	});
	}

	// Modify AAD
	for (int b = 0; b < aad.length; b++) {
	for (int bit = 0; bit < 8; bit++) {
	byte[] modified = Arrays.copyOf(aad, aad.length);
	modified[b] ^= (byte) (1 << bit);
	assertThrows(
	AEADBadTagException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, ciphertext, modified);
	});
	}
	}
	}

	@Test
	public void testNullPlaintextOrCiphertext() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	InsecureNonceChaCha20Poly1305 cipher =
	createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	byte[] aad = new byte[] {1, 2, 3};
	assertThrows(
	NullPointerException.class,
	() -> {
	byte[] unused = cipher.encrypt(nonce, null, aad);
	});
	assertThrows(
	NullPointerException.class,
	() -> {
	byte[] unused = cipher.encrypt(nonce, null, null);
	});
	assertThrows(
	NullPointerException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, null, aad);
	});
	assertThrows(
	NullPointerException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, null, null);
	});
	}

	@Test
	public void testEmptyAssociatedData() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	byte[] aad = new byte[0];
	InsecureNonceChaCha20Poly1305 cipher =
	createInstance(Random.randBytes(KEY_SIZE_IN_BYTES));
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	for (int messageSize = 0; messageSize < 75; messageSize++) {
	byte[] message = Random.randBytes(messageSize);
	{ // encrypting with aad as a 0-length array
	byte[] ciphertext = cipher.encrypt(nonce, message, aad);
	byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
	assertArrayEquals(message, decrypted);
	byte[] decrypted2 = cipher.decrypt(nonce, ciphertext, null);
	assertArrayEquals(message, decrypted2);
	byte[] badAad = new byte[] {1, 2, 3};
	assertThrows(
	AEADBadTagException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, ciphertext, badAad);
	});
	}
	{ // encrypting with aad equal to null
	byte[] ciphertext = cipher.encrypt(nonce, message, null);
	byte[] decrypted = cipher.decrypt(nonce, ciphertext, aad);
	assertArrayEquals(message, decrypted);
	byte[] decrypted2 = cipher.decrypt(nonce, ciphertext, null);
	assertArrayEquals(message, decrypted2);
	byte[] badAad = new byte[] {1, 2, 3};
	assertThrows(
	AEADBadTagException.class,
	() -> {
	byte[] unused = cipher.decrypt(nonce, ciphertext, badAad);
	});
	}
	}
	}

	/**
	* This test simply checks that multiple ciphertexts of the same message with a different nonce
	* are distinct.
	*/
	@Test
	public void testNonce() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	byte[] key = Random.randBytes(KEY_SIZE_IN_BYTES);
	InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
	byte[] message = new byte[0];
	byte[] aad = new byte[0];
	HashSet<String> ciphertexts = new HashSet<>();
	final int samples = 1 << 10;
	for (int i = 0; i < samples; i++) {
	byte[] nonce = Random.randBytes(NONCE_SIZE_IN_BYTES);
	byte[] ct = cipher.encrypt(nonce, message, aad);
	String ctHex = TestUtil.hexEncode(ct);
	assertThat(ciphertexts).doesNotContain(ctHex);
	ciphertexts.add(ctHex);
	}
	assertThat(ciphertexts).hasSize(samples);
	}

	@Test
	public void testWycheproofVectors() throws Exception {
	Assume.assumeFalse(TinkFips.useOnlyFips());

	JsonObject json =
	WycheproofTestUtil.readJson(
	"../wycheproof/testvectors/chacha20_poly1305_test.json");
	int errors = 0;
	JsonArray testGroups = json.getAsJsonArray("testGroups");
	for (int i = 0; i < testGroups.size(); i++) {
	JsonObject group = testGroups.get(i).getAsJsonObject();
	JsonArray tests = group.getAsJsonArray("tests");
	for (int j = 0; j < tests.size(); j++) {
	JsonObject testcase = tests.get(j).getAsJsonObject();
	String tcId =
	String.format(
	"testcase %d (%s)",
	testcase.get("tcId").getAsInt(), testcase.get("comment").getAsString());
	byte[] iv = Hex.decode(testcase.get("iv").getAsString());
	byte[] key = Hex.decode(testcase.get("key").getAsString());
	byte[] msg = Hex.decode(testcase.get("msg").getAsString());
	byte[] aad = Hex.decode(testcase.get("aad").getAsString());
	byte[] ct = Hex.decode(testcase.get("ct").getAsString());
	byte[] tag = Hex.decode(testcase.get("tag").getAsString());
	byte[] ciphertext = Bytes.concat(ct, tag);
	// Result is one of "valid", "invalid", "acceptable".
	// "valid" are test vectors with matching plaintext, ciphertext and tag.
	// "invalid" are test vectors with invalid parameters or invalid ciphertext and tag.
	// "acceptable" are test vectors with weak parameters or legacy formats.
	String result = testcase.get("result").getAsString();
	try {
	InsecureNonceChaCha20Poly1305 cipher = createInstance(key);
	// Encryption.
	byte[] encrypted = cipher.encrypt(iv, msg, aad);
	boolean ciphertextMatches = TestUtil.arrayEquals(encrypted, ciphertext);
	if (result.equals("valid") && !ciphertextMatches) {
	System.err.printf(
	"FAIL %s: incorrect encryption, result: %s, expected: %s%n",
	tcId, Hex.encode(encrypted), Hex.encode(ciphertext));
	errors++;
	}
	// Decryption.
	byte[] decrypted = cipher.decrypt(iv, ciphertext, aad);
	boolean plaintextMatches = TestUtil.arrayEquals(decrypted, msg);
	if (result.equals("invalid")) {
	System.out.printf(
	"FAIL %s: accepting invalid ciphertext, cleartext: %s, decrypted: %s%n",
	tcId, Hex.encode(msg), Hex.encode(decrypted));
	errors++;
	} else {
	if (!plaintextMatches) {
	System.out.printf(
	"FAIL %s: incorrect decryption, result: %s, expected: %s%n",
	tcId, Hex.encode(decrypted), Hex.encode(msg));
	errors++;
	}
	}
	} catch (GeneralSecurityException ex) {
	if (result.equals("valid")) {
	System.out.printf("FAIL %s: cannot decrypt, exception %s%n", tcId, ex);
	errors++;
	}
	}
	}
	}
	assertEquals(0, errors);
	}

	@Test
	public void testFailIfFipsModuleNotAvailable() throws Exception {
	Assume.assumeTrue(TinkFips.useOnlyFips());

	byte[] key = Random.randBytes(32);
	assertThrows(
	GeneralSecurityException.class,
	() -> new InsecureNonceChaCha20Poly1305(key));
	}
	}