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diff --git a/java/com/tigervnc/rdr/AESEAXCipher.java b/java/com/tigervnc/rdr/AESEAXCipher.java
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+/* Copyright (C) 2022 Dinglan Peng
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ * USA.
+ */
+
+package com.tigervnc.rdr;
+
+import java.util.Arrays;
+
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
+import java.security.InvalidAlgorithmParameterException;
+
+import javax.crypto.Cipher;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+import javax.crypto.BadPaddingException;
+import javax.crypto.IllegalBlockSizeException;
+import javax.crypto.NoSuchPaddingException;
+
+public class AESEAXCipher {
+    
+  private static final byte[] zeroBlock = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+  private static final byte[] prefixBlock0 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+  private static final byte[] prefixBlock1 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
+  private static final byte[] prefixBlock2 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2};
+  private static final int[] lut = {0x0,0x87,0x0e,0x89};
+
+  public AESEAXCipher(byte[] key)
+  {
+    try {
+      Cipher blockCipher = Cipher.getInstance("AES");
+      cbcCipher = Cipher.getInstance("AES/CBC/NOPADDING");
+      ctrCipher = Cipher.getInstance("AES/CTR/NOPADDING");
+      keySpec = new SecretKeySpec(key, "AES");
+      blockCipher.init(Cipher.ENCRYPT_MODE, keySpec);
+      cbcCipher.init(Cipher.ENCRYPT_MODE, keySpec,
+                     new IvParameterSpec(zeroBlock));
+      subKey1 = Arrays.copyOfRange(blockCipher.doFinal(zeroBlock), 0, 16);
+      subKey2 = new byte[16];
+      int v = (subKey1[0] & 0xff) >>> 6;
+      for (int i = 0; i < 15; i++) {
+        subKey2[i] = (byte)(((subKey1[i + 1] & 0xff) >>> 6) |
+                            ((subKey1[i] & 0xff) << 2));
+        subKey1[i] = (byte)(((subKey1[i + 1] & 0xff) >>> 7) |
+                            ((subKey1[i] & 0xff) << 1));
+      }
+      subKey2[14] ^= v >>> 1;
+      subKey2[15] = (byte)(((subKey1[15] & 0xff) << 2) ^ lut[v]);
+      subKey1[15] = (byte)(((subKey1[15] & 0xff) << 1) ^ lut[v >>> 1]);
+    } catch (NoSuchAlgorithmException | NoSuchPaddingException e) {
+      throw new Exception("AESEAXCipher: AES algorithm is not supported");
+    } catch (IllegalBlockSizeException | BadPaddingException |
+             InvalidKeyException | InvalidAlgorithmParameterException e) {
+      throw new Exception("AESEAXCipher: invalid key");
+    }
+  }
+
+  private void encryptCTR(byte[] input, int inputOffset, int inputLength,
+                          byte[] output, int outputOffset, byte[] iv)
+  {
+    try {
+      ctrCipher.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(iv));
+      ctrCipher.doFinal(input, inputOffset, inputLength, output, outputOffset);
+    } catch (java.lang.Exception e) {
+      throw new Exception("AESEAXCipher: " + e.toString());
+    }
+  }
+
+  private byte[] computeCMAC(byte[] input, int offset,
+                             int length, byte[] prefix)
+  {
+    int n = length / 16;
+    int m = (length + 15) / 16;
+    int r = length - n * 16;
+    byte[] cbcData = new byte[(m + 1) * 16];
+    System.arraycopy(prefix, 0, cbcData, 0, 16);
+    System.arraycopy(input, offset, cbcData, 16, length);
+    
+    if (r == 0) {
+      for (int i = 0; i < 16; i++) {
+        cbcData[n * 16 + i] ^= subKey1[i] & 0xff;
+      }
+    } else {
+      cbcData[(n + 1) * 16 + r] = (byte)0x80;
+      for (int i = 0; i < 16; i++) {
+        cbcData[(n + 1) * 16 + i] ^= subKey2[i] & 0xff;
+      }
+    }
+    try {
+      byte[] encrypted = cbcCipher.doFinal(cbcData);
+      return Arrays.copyOfRange(encrypted, encrypted.length - 16, encrypted.length - 0);
+    } catch (java.lang.Exception e) {
+      throw new Exception("AESEAXCipher: " + e.getMessage());
+    }
+  }
+
+  public void encrypt(byte[] input, int inputOffset, int inputLength,
+                      byte[] ad,  int adOffset, int adLength,
+                      byte[] nonce,
+                      byte[] output, int outputOffset,
+                      byte[] mac, int macOffset)
+  {
+    byte[] nCMAC = computeCMAC(nonce, 0, nonce.length, prefixBlock0);
+    encryptCTR(input, inputOffset, inputLength, output, outputOffset, nCMAC);
+    byte[] adCMAC = computeCMAC(ad, adOffset, adLength, prefixBlock1);
+    byte[] m = computeCMAC(output, outputOffset, inputLength, prefixBlock2);
+    for (int i = 0; i < 16; i++) {
+      mac[macOffset + i] = (byte)((m[i] & 0xff) ^
+                                  (nCMAC[i] & 0xff) ^
+                                  (adCMAC[i] & 0xff));
+    }
+  }
+
+  public void decrypt(byte[] input, int inputOffset, int inputLength,
+                      byte[] ad,  int adOffset, int adLength,
+                      byte[] nonce,
+                      byte[] output, int outputOffset,
+                      byte[] mac, int macOffset)
+  {
+    byte[] nCMAC = computeCMAC(nonce, 0, nonce.length, prefixBlock0);
+    byte[] adCMAC = computeCMAC(ad, adOffset, adLength, prefixBlock1);
+    byte[] m = computeCMAC(input, inputOffset, inputLength, prefixBlock2);
+    for (int i = 0; i < 16; i++) {
+      byte x = (byte)((m[i] & 0xff) ^ (nCMAC[i] & 0xff) ^ (adCMAC[i] & 0xff));
+      if (x != mac[macOffset + i])
+        throw new Exception("AESEAXCipher: failed to authenticate message"); 
+    }
+    encryptCTR(input, inputOffset, inputLength, output, outputOffset, nCMAC);
+  }
+
+  private SecretKeySpec keySpec;
+  private Cipher ctrCipher;
+  private Cipher cbcCipher;
+  private byte[] subKey1;
+  private byte[] subKey2;
+}