Java Tutorial/Security/MD5 Message Digest algorithm
Содержание
- 1 Check password based on MD5
- 2 Check password salt based on MD5
- 3 creates an MD5 message digest from a file and displays it to the screen BASE64 Encoded.
- 4 Creating a Keyed Digest Using MD5
- 5 Encode an MD5 digest into a String.
- 6 Get MD5 Base64
- 7 Hash 32 String
- 8 Hash 64 String
- 9 MD5 BASE64 checksum for the specified input string.
- 10 MD5 hashing: Encodes a string
- 11 MD5 MessageDigest your message
- 12 MD5 String
- 13 MD5 your password
- 14 Password Authenticator
- 15 Password Storage Example
- 16 Set password salt
Check password based on MD5
import java.io.BufferedReader;
import java.io.FileReader;
import java.security.MessageDigest;
public class MainClass {
public static void main(String args[]) throws Exception {
String name = "";
String passwd = "";
BufferedReader in = new BufferedReader(new FileReader("passwd.txt"));
while ((name = in.readLine()) != null) {
passwd = in.readLine();
if (name.equals(args[0])) {
break;
}
}
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(args[1].getBytes("UTF8"));
byte s[] = m.digest();
String result = "";
for (int i = 0; i < s.length; i++) {
result += Integer.toHexString((0x000000ff & s[i]) | 0xffffff00).substring(6);
}
System.out.println(name.equals(args[0]) && result.equals(passwd));
}
}
Check password salt based on MD5
import java.security.MessageDigest;
public class MainClass {
public static void main(String args[]) throws Exception {
String name = "name";
String passwd = "password";
String salts = "12,12,12";
String salttmp[] = salts.split(",");
byte salt[] = new byte[salttmp.length];
for (int i = 0; i < salt.length; i++) {
salt[i] = Byte.parseByte(salttmp[i]);
}
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(salt);
m.update("name".getBytes("UTF8"));
byte s[] = m.digest();
String result = "";
for (int i = 0; i < s.length; i++) {
result += Integer.toHexString((0x000000ff & s[i]) | 0xffffff00).substring(6);
}
System.out.println(result.equals(passwd));
}
}
creates an MD5 message digest from a file and displays it to the screen BASE64 Encoded.
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.security.MessageDigest;
import sun.misc.BASE64Encoder;
public class MainClass {
public static void main(String[] args) throws Exception {
MessageDigest md = MessageDigest.getInstance("MD5");
BufferedInputStream in = new BufferedInputStream(new FileInputStream("inputfile.txt"));
int theByte = 0;
while ((theByte = in.read()) != -1) {
md.update((byte) theByte);
}
in.close();
byte[] theDigest = md.digest();
System.out.println(new BASE64Encoder().encode(theDigest));
}
}
Creating a Keyed Digest Using MD5
import java.security.MessageDigest;
public class Main {
public static void main(String[] a) throws Exception {
byte[] buffer = new byte[10000];
byte[] key = new byte[8];
MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update(buffer);
byte[] k = md5.digest(key);
}
}
Encode an MD5 digest into a String.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
/**
* Encode an MD5 digest into a String.
* <p>
* The 128 bit MD5 hash is converted into a 32 character long String.
* Each character of the String is the hexadecimal representation of 4 bits
* of the digest.
*
* @author Remy Maucherat
* @version $Revision: 515 $ $Date: 2008-03-17 22:02:23 +0100 (Mon, 17 Mar 2008) $
*/
public final class MD5Encoder {
// ----------------------------------------------------- Instance Variables
private static final char[] hexadecimal =
{"0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
"a", "b", "c", "d", "e", "f"};
// --------------------------------------------------------- Public Methods
/**
* Encodes the 128 bit (16 bytes) MD5 into a 32 character String.
*
* @param binaryData Array containing the digest
* @return Encoded MD5, or null if encoding failed
*/
public String encode( byte[] binaryData ) {
if (binaryData.length != 16)
return null;
char[] buffer = new char[32];
for (int i=0; i<16; i++) {
int low = (int) (binaryData[i] & 0x0f);
int high = (int) ((binaryData[i] & 0xf0) >> 4);
buffer[i*2] = hexadecimal[high];
buffer[i*2 + 1] = hexadecimal[low];
}
return new String(buffer);
}
}
Get MD5 Base64
/*
* $Header: /cvsroot/mvnforum/mvnforum/contrib/phpbb2mvnforum/src/org/mvnforum/util/MD5.java,v 1.6 2007/01/15 10:27:31 dungbtm Exp $
* $Author: dungbtm $
* $Revision: 1.6 $
* $Date: 2007/01/15 10:27:31 $
*
*
* Copyright (C) 2002-2007 by MyVietnam.net
*
* All copyright notices regarding mvnForum MUST remain
* intact in the scripts and in the outputted HTML.
* The "powered by" text/logo with a link back to
* http://www.mvnForum.ru and http://www.MyVietnam.net in
* the footer of the pages MUST remain visible when the pages
* are viewed on the internet or intranet.
*
* This program 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
* any later version.
*
* This program 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 program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Support can be obtained from support forums at:
* http://www.mvnForum.ru/mvnforum/index
*
* Correspondence and Marketing Questions can be sent to:
* info at MyVietnam net
*
* @author:
*/
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import sun.misc.BASE64Encoder;
// The JavaReference.ru Software License, Version 1.0
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/**
* @author anandh
*/
public class MD5 {
static char[] carr = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
public static String getBase64FromHEX(String input) {
byte barr[] = new byte[16];
int bcnt = 0;
for (int i = 0; i < 32; i += 2) {
char c1 = input.charAt(i);
char c2 = input.charAt(i + 1);
int i1 = intFromChar(c1);
int i2 = intFromChar(c2);
barr[bcnt] = 0;
barr[bcnt] |= (byte) ((i1 & 0x0F) << 4);
barr[bcnt] |= (byte) (i2 & 0x0F);
bcnt++;
}
BASE64Encoder encoder = new BASE64Encoder();
return encoder.encode(barr);
}
public static synchronized String getMD5_Base64(String input) {
// please note that we dont use digest, because if we
// cannot get digest, then the second time we have to call it
// again, which will fail again
MessageDigest digest = null;
try {
digest = MessageDigest.getInstance("MD5");
} catch (Exception ex) {
ex.printStackTrace();
}
if (digest == null)
return input;
// now everything is ok, go ahead
try {
digest.update(input.getBytes("UTF-8"));
} catch (java.io.UnsupportedEncodingException ex) {
ex.printStackTrace();
}
byte[] rawData = digest.digest();
BASE64Encoder bencoder = new BASE64Encoder();
return bencoder.encode(rawData);
}
private static int intFromChar(char c) {
char clower = Character.toLowerCase(c);
for (int i = 0; i < carr.length; i++) {
if (clower == carr[i]) {
return i;
}
}
return 0;
}
public static void main(String[] args) {
//String password = args[0];
String password = "test";
MessageDigest digest = null;
try {
digest = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
try {
digest.update(password.getBytes("UTF-8"));
} catch (UnsupportedEncodingException ex) {
ex.printStackTrace();
}
byte[] rawData = digest.digest();
StringBuffer printable = new StringBuffer();
for (int i = 0; i < rawData.length; i++) {
printable.append(carr[((rawData[i] & 0xF0) >> 4)]);
printable.append(carr[(rawData[i] & 0x0F)]);
}
String phpbbPassword = printable.toString();
System.out.println("PHPBB : " + phpbbPassword);
System.out.println("MVNFORUM : " + getMD5_Base64(password));
System.out.println("PHPBB->MVNFORUM : " + getBase64FromHEX(phpbbPassword));
}
}
Hash 32 String
/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Contact info: lobochief@users.sourceforge.net
*/
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
public class Strings
{
private static final MessageDigest MESSAGE_DIGEST;
public static final String[] EMPTY_ARRAY = new String[0];
static {
MessageDigest md;
try {
md = MessageDigest.getInstance("MD5");
} catch(NoSuchAlgorithmException err) {
throw new IllegalStateException();
}
MESSAGE_DIGEST = md;
}
private static final String HEX_CHARS = "0123456789ABCDEF";
public static String getMD5(String source) {
byte[] bytes;
try {
bytes = source.getBytes("UTF-8");
} catch(java.io.UnsupportedEncodingException ue) {
throw new IllegalStateException(ue);
}
byte[] result;
synchronized(MESSAGE_DIGEST) {
MESSAGE_DIGEST.update(bytes);
result = MESSAGE_DIGEST.digest();
}
char[] resChars = new char[32];
int len = result.length;
for(int i = 0; i < len; i++) {
byte b = result[i];
int lo4 = b & 0x0F;
int hi4 = (b & 0xF0) >> 4;
resChars[i*2] = HEX_CHARS.charAt(hi4);
resChars[i*2 + 1] = HEX_CHARS.charAt(lo4);
}
return new String(resChars);
}
public static String getHash32(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 8);
}
public static String getHash64(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 16);
}
}
Hash 64 String
/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Contact info: lobochief@users.sourceforge.net
*/
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
public class Strings
{
private static final MessageDigest MESSAGE_DIGEST;
public static final String[] EMPTY_ARRAY = new String[0];
static {
MessageDigest md;
try {
md = MessageDigest.getInstance("MD5");
} catch(NoSuchAlgorithmException err) {
throw new IllegalStateException();
}
MESSAGE_DIGEST = md;
}
private static final String HEX_CHARS = "0123456789ABCDEF";
public static String getMD5(String source) {
byte[] bytes;
try {
bytes = source.getBytes("UTF-8");
} catch(java.io.UnsupportedEncodingException ue) {
throw new IllegalStateException(ue);
}
byte[] result;
synchronized(MESSAGE_DIGEST) {
MESSAGE_DIGEST.update(bytes);
result = MESSAGE_DIGEST.digest();
}
char[] resChars = new char[32];
int len = result.length;
for(int i = 0; i < len; i++) {
byte b = result[i];
int lo4 = b & 0x0F;
int hi4 = (b & 0xF0) >> 4;
resChars[i*2] = HEX_CHARS.charAt(hi4);
resChars[i*2 + 1] = HEX_CHARS.charAt(lo4);
}
return new String(resChars);
}
public static String getHash32(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 8);
}
public static String getHash64(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 16);
}
}
MD5 BASE64 checksum for the specified input string.
import javax.swing.JOptionPane;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* MD5 common utils. Check and calculate MD5 BASE64 sum.
*
* @author Luigi Zurolo - Liscio Luca
* @version 1.1
*/
public class MD5 {
/**
* MD5 BASE64 checksum for the specified input string.
*
* @param input -
* Specified input string
* @return String - MD5 BASE64 sum
*/
public static String checkMD5(String input) {
try {
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(input.getBytes());
byte[] enc = md.digest();
String md5Sum = new sun.misc.BASE64Encoder().encode(enc);
return md5Sum;
} catch (NoSuchAlgorithmException nsae) {
System.out.println(nsae.getMessage());
return null;
}
}
}
MD5 hashing: Encodes a string
/*
* Copyright (c) JForum Team
* All rights reserved.
*
* Redistribution and use in source and binary forms,
* with or without modification, are permitted provided
* that the following conditions are met:
*
* 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
* 2) Redistributions in binary form must reproduce the
* above copyright notice, this list of conditions and
* the following disclaimer in the documentation and/or
* other materials provided with the distribution.
* 3) Neither the name of "Rafael Steil" nor
* the names of its contributors may be used to endorse
* or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT
* HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
*
* This file creation date: Mar 29, 2003 / 1:15:50 AM
* The JForum Project
* http://www.jforum.net
*/
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* Encodes a string using MD5 hashing
*
* @author Rafael Steil
* @version $Id: MD5.java,v 1.7 2006/08/23 02:13:44 rafaelsteil Exp $
*/
public class MD5
{
/**
* Encodes a string
*
* @param str String to encode
* @return Encoded String
* @throws NoSuchAlgorithmException
*/
public static String crypt(String str)
{
if (str == null || str.length() == 0) {
throw new IllegalArgumentException("String to encript cannot be null or zero length");
}
StringBuffer hexString = new StringBuffer();
try {
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(str.getBytes());
byte[] hash = md.digest();
for (int i = 0; i < hash.length; i++) {
if ((0xff & hash[i]) < 0x10) {
hexString.append("0" + Integer.toHexString((0xFF & hash[i])));
}
else {
hexString.append(Integer.toHexString(0xFF & hash[i]));
}
}
}
catch (NoSuchAlgorithmException e) {
throw new RuntimeException("" + e);
}
return hexString.toString();
}
}
MD5 MessageDigest your message
import java.io.FileInputStream;
import java.security.DigestInputStream;
import java.security.MessageDigest;
public class MainClass {
public static void main(String args[]) throws Exception {
MessageDigest m = MessageDigest.getInstance("MD5");
FileInputStream fin = new FileInputStream(args[0]);
DigestInputStream din = new DigestInputStream(fin, m);
din.on(false);
int b;
while ((b = din.read()) != -1) {
if (b == "X") {
din.on(true);
}
}
byte s[] = m.digest();
for (int i = 0; i < s.length; i++) {
System.out.print( Integer.toHexString((0x000000ff & s[i]) | 0xffffff00).substring(6));
}
}
}
MD5 String
/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Contact info: lobochief@users.sourceforge.net
*/
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
public class Strings
{
private static final MessageDigest MESSAGE_DIGEST;
public static final String[] EMPTY_ARRAY = new String[0];
static {
MessageDigest md;
try {
md = MessageDigest.getInstance("MD5");
} catch(NoSuchAlgorithmException err) {
throw new IllegalStateException();
}
MESSAGE_DIGEST = md;
}
private static final String HEX_CHARS = "0123456789ABCDEF";
public static String getMD5(String source) {
byte[] bytes;
try {
bytes = source.getBytes("UTF-8");
} catch(java.io.UnsupportedEncodingException ue) {
throw new IllegalStateException(ue);
}
byte[] result;
synchronized(MESSAGE_DIGEST) {
MESSAGE_DIGEST.update(bytes);
result = MESSAGE_DIGEST.digest();
}
char[] resChars = new char[32];
int len = result.length;
for(int i = 0; i < len; i++) {
byte b = result[i];
int lo4 = b & 0x0F;
int hi4 = (b & 0xF0) >> 4;
resChars[i*2] = HEX_CHARS.charAt(hi4);
resChars[i*2 + 1] = HEX_CHARS.charAt(lo4);
}
return new String(resChars);
}
public static String getHash32(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 8);
}
public static String getHash64(String source) throws UnsupportedEncodingException {
String md5 = getMD5(source);
return md5.substring(0, 16);
}
}
MD5 your password
import java.security.MessageDigest;
public class MainClass {
public static void main(String args[]) throws Exception {
String name = "name";
String passwd = "password";
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(passwd.getBytes("UTF8"));
byte s[] = m.digest();
String result = "";
for (int i = 0; i < s.length; i++) {
result += Integer.toHexString((0x000000ff & s[i]) | 0xffffff00).substring(6);
}
System.out.println(name);
System.out.println(result);
}
}
/*name
5f4dcc3b5aa765d61d8327deb882cf99*/
Password Authenticator
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.security.MessageDigest;
import java.util.Arrays;
public class MainClass {
public static void main(String[] args) throws Exception {
authenticatePassword("password");
}
private static void authenticatePassword(String password) throws Exception {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
FileInputStream fis = new FileInputStream("password");
int theByte = 0;
while ((theByte = fis.read()) != -1) {
baos.write(theByte);
}
fis.close();
byte[] hashedPasswordWithSalt = baos.toByteArray();
baos.reset();
byte[] salt = new byte[12];
System.arraycopy(hashedPasswordWithSalt, 0, salt, 0, 12);
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(salt);
md.update(password.getBytes("UTF8"));
byte[] digest = md.digest();
byte[] digestInFile = new byte[hashedPasswordWithSalt.length - 12];
System.arraycopy(hashedPasswordWithSalt, 12, digestInFile, 0,
hashedPasswordWithSalt.length - 12);
System.out.println(Arrays.equals(digest, digestInFile));
}
}
Password Storage Example
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.security.MessageDigest;
import java.security.SecureRandom;
import java.util.Arrays;
public class MainClass {
public static void main(String[] args) throws Exception {
createPassword("password");
}
private static void createPassword(String password) throws Exception {
SecureRandom random = new SecureRandom();
byte[] salt = new byte[12];
random.nextBytes(salt);
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(salt);
md.update(password.getBytes("UTF8"));
byte[] digest = md.digest();
FileOutputStream fos = new FileOutputStream("password");
fos.write(salt);
fos.write(digest);
fos.close();
}
}
Set password salt
import java.security.MessageDigest;
import java.util.Random;
public class MainClass {
public static void main(String args[]) throws Exception {
String name = "name";
String passwd = "password";
Random rand = new Random();
byte[] salt = new byte[12];
rand.nextBytes(salt);
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(salt);
m.update(passwd.getBytes("UTF8"));
byte s[] = m.digest();
String result = "";
for (int i = 0; i < s.length; i++) {
result += Integer.toHexString((0x000000ff & s[i]) | 0xffffff00).substring(6);
}
System.out.println(name);
for (int i = 0; i < salt.length; i++) {
System.out.print(salt[i] + ",");
}
System.out.println(result);
}
}
/*name
72,83,-8,78,-82,125,0,-37,-116,-83,-72,27,460a21b49082e5268a4016bfa2e2885c*/
