Implemented MD5 just like the SHA1 util

smack-core/src/main/java/org/jivesoftware/smack/util/ByteUtils.java

@@ -16,28 +16,7 @@
  */
 package org.jivesoftware.smack.util;
 
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
-
 public class ByteUtils {
-
-    private static MessageDigest md5Digest;
-
-    public synchronized static byte[] md5(byte[] data) {
-        if (md5Digest == null) {
-            try {
-                md5Digest = MessageDigest.getInstance(StringUtils.MD5);
-            }
-            catch (NoSuchAlgorithmException nsae) {
-                // Smack wont be able to function normally if this exception is thrown, wrap it into
-                // an ISE and make the user aware of the problem.
-                throw new IllegalStateException(nsae);
-            }
-        }
-        md5Digest.update(data);
-        return md5Digest.digest();
-    }
-
     public static byte[] concact(byte[] arrayOne, byte[] arrayTwo) {
         int combinedLength = arrayOne.length + arrayTwo.length;
         byte[] res = new byte[combinedLength];

smack-core/src/main/java/org/jivesoftware/smack/util/MD5.java

@@ -0,0 +1,56 @@
+/**
+ *
+ * Copyright © 2014 Florian Schmaus
+ *
+ * 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 org.jivesoftware.smack.util;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class MD5 {
+
+    /**
+     * Used by the hash method.
+     */
+    private static MessageDigest MD5_DIGEST;
+
+    static {
+        try {
+            MD5_DIGEST = MessageDigest.getInstance(StringUtils.MD5);
+        }
+        catch (NoSuchAlgorithmException e) {
+            // Smack wont be able to function normally if this exception is thrown, wrap it into
+            // an ISE and make the user aware of the problem.
+            throw new IllegalStateException(e);
+        }
+    }
+
+    public static synchronized byte[] bytes(byte[] bytes) {
+        return MD5_DIGEST.digest(bytes);
+    }
+
+    public static byte[] bytes(String string) {
+        return bytes(StringUtils.toBytes(string));
+    }
+
+    public static String hex(byte[] bytes) {
+        return StringUtils.encodeHex(bytes(bytes));
+    }
+
+    public static String hex(String string) {
+        return hex(StringUtils.toBytes(string));
+    }
+
+}

smack-sasl-provided/src/main/java/org/jivesoftware/smack/sasl/provided/SASLDigestMD5Mechanism.java

@@ -21,6 +21,7 @@ import javax.security.auth.callback.CallbackHandler;
 import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.sasl.SASLMechanism;
 import org.jivesoftware.smack.util.ByteUtils;
+import org.jivesoftware.smack.util.MD5;
 import org.jivesoftware.smack.util.StringUtils;
 
 public class SASLDigestMD5Mechanism extends SASLMechanism {
@@ -124,12 +125,12 @@ public class SASLDigestMD5Mechanism extends SASLMechanism {
                 throw new SmackException("nonce value not present in initial challenge");
             }
             // RFC 2831 2.1.2.1 defines A1, A2, KD and response-value
-            byte[] a1FirstPart = ByteUtils.md5(toBytes(authenticationId + ':' + serviceName + ':'
-                            + password));
+            byte[] a1FirstPart = MD5.bytes(authenticationId + ':' + serviceName + ':'
+                            + password);
             cnonce = StringUtils.randomString(32);
             byte[] a1 = ByteUtils.concact(a1FirstPart, toBytes(':' + nonce + ':' + cnonce));
             digestUri = "xmpp/" + serviceName;
-            hex_hashed_a1 = StringUtils.encodeHex(ByteUtils.md5(a1));
+            hex_hashed_a1 = StringUtils.encodeHex(MD5.bytes(a1));
             String responseValue = calcResponse(DigestType.ClientResponse);
             // @formatter:off
             // See RFC 2831 2.1.2 digest-response
@@ -189,7 +190,7 @@ public class SASLDigestMD5Mechanism extends SASLMechanism {
         }
         a2.append(':');
         a2.append(digestUri);
-        String hex_hashed_a2 = StringUtils.encodeHex(ByteUtils.md5(toBytes(a2.toString())));
+        String hex_hashed_a2 = StringUtils.encodeHex(MD5.bytes(a2.toString()));
 
         StringBuilder kd_argument = new StringBuilder();
         kd_argument.append(hex_hashed_a1);
@@ -203,7 +204,7 @@ public class SASLDigestMD5Mechanism extends SASLMechanism {
         kd_argument.append(QOP_VALUE);
         kd_argument.append(':');
         kd_argument.append(hex_hashed_a2);
-        byte[] kd = ByteUtils.md5(toBytes(kd_argument.toString()));
+        byte[] kd = MD5.bytes(kd_argument.toString());
         String responseValue = StringUtils.encodeHex(kd);
         return responseValue;
     }