Various improvements to native cipher so that it now actually destroys Java in terms of speed. Closes #871 - thanks @ninja-

native/src/main/c/NativeCipherImpl.c

@@ -3,54 +3,66 @@
 #include <jni.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #define BYTE unsigned char
 
-jlong Java_net_md_15_bungee_NativeCipherImpl_init
+jlong Java_net_md_15_bungee_NativeCipherImpl_initKey
 (JNIEnv* env, jobject obj, jbyteArray key)
 {
     AES_KEY *aes_key = malloc(sizeof(AES_KEY));
 
-    jboolean isKeyCopy;
-    BYTE *key_bytes = (BYTE*)(*env)->GetByteArrayElements(env, key, &isKeyCopy);
+    jboolean isFieldCopy;
+    BYTE *key_bytes = (BYTE*)(*env)->GetByteArrayElements(env, key, &isFieldCopy);
     int key_length = (*env)->GetArrayLength(env, key) * 8; // in bits
 
     AES_set_encrypt_key(key_bytes, key_length, aes_key);
 
-    if (isKeyCopy) {
+    if (isFieldCopy) {
         (*env)->ReleaseByteArrayElements(env, key, (jbyte*)key_bytes, JNI_ABORT);
     }
+
     return (long) aes_key;
 }
+jlong Java_net_md_15_bungee_NativeCipherImpl_initIV
+(JNIEnv* env, jobject obj, jbyteArray iv)
+{
+    jboolean isFieldCopy;
+    BYTE *iv_bytes = (BYTE*)(*env)->GetByteArrayElements(env, iv, &isFieldCopy);
+    int iv_length = (*env)->GetArrayLength(env, iv);
+
+    BYTE* jni_iv = malloc(iv_length);
+
+    memcpy(jni_iv, iv_bytes, iv_length);
+
+    if (isFieldCopy) {
+        (*env)->ReleaseByteArrayElements(env, iv, (jbyte*)iv_bytes, JNI_ABORT);
+    }
+
+    return (long) jni_iv;
+}
 void Java_net_md_15_bungee_NativeCipherImpl_free
-(JNIEnv* env, jobject obj, jlong key)
+(JNIEnv* env, jobject obj, jlong key, jlong iv)
 {
     free((AES_KEY*)key);
+    free((BYTE*)iv);
 }
 void Java_net_md_15_bungee_NativeCipherImpl_cipher
-(JNIEnv* env, jobject obj, jboolean forEncryption, jlong key, jbyteArray iv, jlong in, jlong out, jint length)
+(JNIEnv* env, jobject obj, jboolean forEncryption, jlong key, jlong iv, jlong in, jlong out, jint length)
 {
     AES_KEY *aes_key = (AES_KEY*)key;
-
     size_t buffer_length = (size_t) length;
 
-    BYTE *input =  (BYTE*) in;
-    BYTE *output =  (BYTE*) out;
-
-    jboolean isCopy;
-    BYTE *iv_bytes = (BYTE*)(*env)->GetByteArrayElements(env, iv, &isCopy);
+    BYTE *input = (BYTE*) in;
+    BYTE *output = (BYTE*) out;
+    BYTE* jni_iv = (BYTE*) iv;
 
     AES_cfb8_encrypt(
       input,                                     // input buffer
       output,                                    // output buffer
       buffer_length,                             // readable bytes
       aes_key,                                   // encryption key
-      iv_bytes,                                  // IV
+      jni_iv,                                    // IV
       NULL,                                      // not needed
       forEncryption ? AES_ENCRYPT : AES_DECRYPT  // encryption mode
     );
-
-    // IV has changed, let's copy it back
-    if (isCopy) {
-      (*env)->ReleaseByteArrayElements(env, iv, (jbyte*)iv_bytes, 0);
-    }
 }

native/src/main/c/net_md_5_bungee_NativeCipherImpl.h

@@ -9,10 +9,17 @@ extern "C" {
 #endif
 /*
  * Class:     net_md_5_bungee_NativeCipherImpl
- * Method:    init
+ * Method:    init_key
  * Signature: ([B)J
  */
-JNIEXPORT jlong JNICALL Java_net_md_15_bungee_NativeCipherImpl_init
+JNIEXPORT jlong JNICALL Java_net_md_15_bungee_NativeCipherImpl_initKey
+  (JNIEnv *, jobject, jbyteArray);
+/*
+ * Class:     net_md_5_bungee_NativeCipherImpl
+ * Method:    init_iv
+ * Signature: ([B)J
+ */
+JNIEXPORT jlong JNICALL Java_net_md_15_bungee_NativeCipherImpl_initIV
   (JNIEnv *, jobject, jbyteArray);
 
 /*
@@ -21,7 +28,7 @@ JNIEXPORT jlong JNICALL Java_net_md_15_bungee_NativeCipherImpl_init
  * Signature: (J)V
  */
 JNIEXPORT void JNICALL Java_net_md_15_bungee_NativeCipherImpl_free
-  (JNIEnv *, jobject, jlong);
+  (JNIEnv *, jobject, jlong, jlong);
 
 /*
  * Class:     net_md_5_bungee_NativeCipherImpl
@@ -29,9 +36,10 @@ JNIEXPORT void JNICALL Java_net_md_15_bungee_NativeCipherImpl_free
  * Signature: (ZJ[BJJI)V
  */
 JNIEXPORT void JNICALL Java_net_md_15_bungee_NativeCipherImpl_cipher
-  (JNIEnv *, jobject, jboolean, jlong, jbyteArray, jlong, jlong, jint);
+  (JNIEnv *, jobject, jboolean, jlong, jlong, jlong, jlong, jint);
 
 #ifdef __cplusplus
 }
 #endif
 #endif
+

native/src/main/java/net/md_5/bungee/NativeCipher.java

@@ -16,13 +16,12 @@ public class NativeCipher implements BungeeCipher
 {
 
     @Getter
-    private final NativeCipherImpl nativeCipher = new NativeCipherImpl();
-    private boolean forEncryption;
-    private byte[] iv;
-    /*============================================================================*/
+    private final static NativeCipherImpl nativeCipher = new NativeCipherImpl();
     private static boolean loaded;
-
-    private long pointer;
+    /*============================================================================*/
+    private boolean forEncryption;
+    private long keyPointer;
+    private long ivPointer;
 
     public static boolean isSupported()
     {
@@ -59,23 +58,18 @@ public class NativeCipher implements BungeeCipher
     @Override
     public void init(boolean forEncryption, SecretKey key) throws GeneralSecurityException
     {
-        if ( pointer != 0 )
-        {
-            nativeCipher.free( pointer );
-        }
+        nativeCipher.free( this.keyPointer, this.ivPointer );
         this.forEncryption = forEncryption;
-        this.iv = key.getEncoded(); // initialize the IV
-        this.pointer = nativeCipher.init( key.getEncoded() );
+
+        byte[] encoded = key.getEncoded();
+        this.keyPointer = nativeCipher.initKey( encoded );
+        this.ivPointer = nativeCipher.initIV( encoded );
     }
 
     @Override
     public void free()
     {
-        if ( pointer != 0 )
-        {
-            nativeCipher.free( pointer );
-            pointer = 0;
-        }
+        nativeCipher.free( keyPointer, ivPointer );
     }
 
     @Override
@@ -84,8 +78,8 @@ public class NativeCipher implements BungeeCipher
         // Smoke tests
         in.memoryAddress();
         out.memoryAddress();
-        Preconditions.checkState( pointer != 0, "Invalid pointer to AES key!" );
-        Preconditions.checkState( iv != null, "Invalid IV!" );
+        Preconditions.checkState( keyPointer != 0, "Invalid pointer to AES key!" );
+        Preconditions.checkState( ivPointer != 0, "Invalid pointer to IV!" );
 
         // Store how many bytes we can cipher
         int length = in.readableBytes();
@@ -93,7 +87,7 @@ public class NativeCipher implements BungeeCipher
         out.ensureWritable( length );
 
         // Cipher the bytes
-        nativeCipher.cipher( forEncryption, pointer, iv, in.memoryAddress() + in.readerIndex(), out.memoryAddress() + out.writerIndex(), length );
+        nativeCipher.cipher( forEncryption, keyPointer, ivPointer, in.memoryAddress() + in.readerIndex(), out.memoryAddress() + out.writerIndex(), length );
 
         // Go to the end of the buffer, all bytes would of been read
         in.readerIndex( in.writerIndex() );

native/src/main/java/net/md_5/bungee/NativeCipherImpl.java

@@ -9,24 +9,33 @@ class NativeCipherImpl
      * @param key the key to for encryption
      * @return the pointer to key
      */
-    native long init(byte[] key);
+    native long initKey(byte[] key);
+
+    /**
+     * Initializes the iv.
+     *
+     * @param iv the iv
+     * @return the pointer to iv
+     */
+    native long initIV(byte[] iv);
 
     /**
      * Frees the key.
      *
      * @param key the pointer to key
+     * @param iv the pointer to iv
      */
-    native void free(long key);
+    native void free(long key, long iv);
 
     /**
      * This method will encrypt some data in AES-CFB8 using the specified key.
      *
      * @param forEncryption encryption / decryption mode
      * @param key the pointer to key
-     * @param iv the iv to use
+     * @param iv the pointer to iv
      * @param in the starting memory address for reading data
      * @param out the starting memory address for writing data
      * @param length the length of data to read / write
      */
-    native void cipher(boolean forEncryption, long key, byte[] iv, long in, long out, int length);
+    native void cipher(boolean forEncryption, long key, long iv, long in, long out, int length);
 }