Cleanup TLS 1.2 GCM nonce generator stuff

Author: peterdettman

tls/src/main/java/org/bouncycastle/tls/crypto/impl/AEADNonceGenerator.java

@@ -1,9 +1,8 @@
 package org.bouncycastle.tls.crypto.impl;
 
-import org.bouncycastle.tls.TlsFatalAlert;
+import java.io.IOException;
 
 public interface AEADNonceGenerator
 {
-    public void generateNonce(byte[] nonce)
-        throws TlsFatalAlert;
+    public void generateNonce(byte[] nonce) throws IOException;
 }

tls/src/main/java/org/bouncycastle/tls/crypto/impl/AEADNonceGeneratorFactory.java

@@ -1,7 +1,5 @@
 package org.bouncycastle.tls.crypto.impl;
 
-import org.bouncycastle.tls.crypto.TlsNonceGenerator;
-
 public interface AEADNonceGeneratorFactory
 {
     AEADNonceGenerator create(byte[] baseNonce, int counterSizeInBits);

tls/src/main/java/org/bouncycastle/tls/crypto/impl/GcmTls12NonceGeneratorUtil.java

@@ -1,26 +1,21 @@
 package org.bouncycastle.tls.crypto.impl;
 
-import java.security.AccessController;
-import java.security.PrivilegedAction;
-
-final public class GcmTls12NonceGeneratorUtil
+public final class GcmTls12NonceGeneratorUtil
 {
-    private static AEADNonceGeneratorFactory tlsNonceGeneratorFactory = null;
+    private static volatile AEADNonceGeneratorFactory globalFactory = null;
 
-    public static void setGcmTlsNonceGeneratorFactory(final AEADNonceGeneratorFactory factory)
+    public static void setGcmTlsNonceGeneratorFactory(AEADNonceGeneratorFactory factory)
     {
-        tlsNonceGeneratorFactory = factory;
+        globalFactory = factory;
     }
 
     public static boolean isGcmFipsNonceGeneratorFactorySet()
     {
-        return tlsNonceGeneratorFactory != null;
+        return globalFactory != null;
     }
 
-    public static AEADNonceGenerator createGcmFipsNonceGenerator(final byte[] baseNonce, final int counterSizeInBits)
+    public static AEADNonceGenerator createGcmFipsNonceGenerator(byte[] baseNonce, int counterSizeInBits)
     {
-        return tlsNonceGeneratorFactory != null
-                ? tlsNonceGeneratorFactory.create(baseNonce, counterSizeInBits)
-                : null;
+        return globalFactory == null ? null : globalFactory.create(baseNonce, counterSizeInBits);
     }
 }

tls/src/main/java/org/bouncycastle/tls/crypto/impl/TlsAEADCipher.java

@@ -13,7 +13,6 @@
 import org.bouncycastle.tls.crypto.TlsCryptoUtils;
 import org.bouncycastle.tls.crypto.TlsDecodeResult;
 import org.bouncycastle.tls.crypto.TlsEncodeResult;
-import org.bouncycastle.tls.crypto.TlsNonceGenerator;
 import org.bouncycastle.tls.crypto.TlsSecret;
 import org.bouncycastle.util.Arrays;
 
@@ -31,7 +30,7 @@ public final class TlsAEADCipher
     private static final int NONCE_RFC7905 = 2;
     private static final long SEQUENCE_NUMBER_PLACEHOLDER = -1L;
 
-    private static final byte[] EPOCH_1 = {0x00, 0x01};
+    private static final byte[] EPOCH_1 = { 0x00, 0x01 };
 
     private final TlsCryptoParameters cryptoParams;
     private final int keySize;
@@ -129,9 +128,9 @@ public TlsAEADCipher(TlsCryptoParameters cryptoParams, TlsAEADCipherImpl encrypt
 
         if (AEAD_GCM == aeadType && GcmTls12NonceGeneratorUtil.isGcmFipsNonceGeneratorFactorySet())
         {
-            final int nonceLength = fixed_iv_length + record_iv_length;
-            final byte[] baseNonce = Arrays.copyOf(encryptNonce, nonceLength);
-            final int counterSizeInBits;
+            int nonceLength = fixed_iv_length + record_iv_length;
+            byte[] baseNonce = Arrays.copyOf(encryptNonce, nonceLength);
+            int counterSizeInBits;
             if (negotiatedVersion.isDTLS())
             {
                 counterSizeInBits = (record_iv_length - 2) * 8; // 48
@@ -142,7 +141,8 @@ public TlsAEADCipher(TlsCryptoParameters cryptoParams, TlsAEADCipherImpl encrypt
             {
                 counterSizeInBits = record_iv_length * 8; // 64
             }
-            gcmFipsNonceGenerator = GcmTls12NonceGeneratorUtil.createGcmFipsNonceGenerator(baseNonce, counterSizeInBits);
+            gcmFipsNonceGenerator = GcmTls12NonceGeneratorUtil.createGcmFipsNonceGenerator(baseNonce,
+                counterSizeInBits);
         }
         else
         {
@@ -181,8 +181,7 @@ public int getPlaintextEncodeLimit(int ciphertextLimit)
     public TlsEncodeResult encodePlaintext(long seqNo, short contentType, ProtocolVersion recordVersion,
         int headerAllocation, byte[] plaintext, int plaintextOffset, int plaintextLength) throws IOException
     {
-        final int nonceSize = encryptNonce.length + record_iv_length;
-        final byte[] nonce = new byte[nonceSize];
+        byte[] nonce = new byte[encryptNonce.length + record_iv_length];
 
         if (null != gcmFipsNonceGenerator)
         {
@@ -192,20 +191,20 @@ public TlsEncodeResult encodePlaintext(long seqNo, short contentType, ProtocolVe
         {
             switch (nonceMode)
             {
-                case NONCE_RFC5288:
-                    System.arraycopy(encryptNonce, 0, nonce, 0, encryptNonce.length);
-                    // RFC 5288/6655: The nonce_explicit MAY be the 64-bit sequence number.
-                    TlsUtils.writeUint64(seqNo, nonce, encryptNonce.length);
-                    break;
-                case NONCE_RFC7905:
-                    TlsUtils.writeUint64(seqNo, nonce, nonce.length - 8);
-                    for (int i = 0; i < encryptNonce.length; ++i)
-                    {
-                        nonce[i] ^= encryptNonce[i];
-                    }
-                    break;
-                default:
-                    throw new TlsFatalAlert(AlertDescription.internal_error);
+            case NONCE_RFC5288:
+                System.arraycopy(encryptNonce, 0, nonce, 0, encryptNonce.length);
+                // RFC 5288/6655: The nonce_explicit MAY be the 64-bit sequence number.
+                TlsUtils.writeUint64(seqNo, nonce, encryptNonce.length);
+                break;
+            case NONCE_RFC7905:
+                TlsUtils.writeUint64(seqNo, nonce, nonce.length - 8);
+                for (int i = 0; i < encryptNonce.length; ++i)
+                {
+                    nonce[i] ^= encryptNonce[i];
+                }
+                break;
+            default:
+                throw new TlsFatalAlert(AlertDescription.internal_error);
             }
         }
 

tls/src/test/java/org/bouncycastle/tls/test/TestAEADGeneratorFactory.java

@@ -13,8 +13,7 @@ private TestAEADGeneratorFactory()
         // no op
     }
 
-    @Override
-    public AEADNonceGenerator create(final byte[] baseNonce, final int counterSizeInBits)
+    public AEADNonceGenerator create(byte[] baseNonce, int counterSizeInBits)
     {
         return new TestAEADNonceGenerator(baseNonce, counterSizeInBits);
     }

tls/src/test/java/org/bouncycastle/tls/test/TestAEADNonceGenerator.java

@@ -1,6 +1,5 @@
 package org.bouncycastle.tls.test;
 
-import org.bouncycastle.tls.crypto.TlsNonceGenerator;
 import org.bouncycastle.tls.crypto.impl.AEADNonceGenerator;
 import org.bouncycastle.util.Arrays;
 
@@ -14,7 +13,7 @@ class TestAEADNonceGenerator
     private long counterValue;
     private boolean counterExhausted;
 
-    TestAEADNonceGenerator(final byte[] baseNonce, final int counterBits)
+    TestAEADNonceGenerator(byte[] baseNonce, int counterBits)
     {
         this.baseNonce = Arrays.copyOf(baseNonce, baseNonce.length);
         this.counterMask = -1L >>> (64 - counterBits);
@@ -24,7 +23,6 @@ class TestAEADNonceGenerator
         this.counterExhausted = false;
     }
 
-    @Override
     public void generateNonce(byte[] nonce)
     {
         if (nonce.length != baseNonce.length)
@@ -38,7 +36,7 @@ public void generateNonce(byte[] nonce)
         }
 
         System.arraycopy(baseNonce, 0, nonce, 0, baseNonce.length);
-        final int offset = baseNonce.length - counterBytes;
+        int offset = baseNonce.length - counterBytes;
 
         for (int i = 0; i < counterBytes; i++)
         {