I understand how it works but if I want to print out the MD5 as String how would I do that?
public static void getMD5(String fileName) throws Exception{
InputStream input = new FileInputStream(fileName);
byte[] buffer = new byte[1024];
MessageDigest hash = MessageDigest.getInstance("MD5");
int read;
do {
read = input.read(buffer);
if (read > 0) {
hash.update(buffer, 0, read);
}
} while (read != -1);
input.close();
}
You can get it writing less:
String hex = (new HexBinaryAdapter()).marshal(md5.digest(YOUR_STRING.getBytes()))
String input = "168";
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] md5sum = md.digest(input.getBytes());
String output = String.format("%032X", new BigInteger(1, md5sum));
or
DatatypeConverter.printHexBinary( MessageDigest.getInstance("MD5").digest("a".getBytes("UTF-8")))
Try this
StringBuffer hexString = new StringBuffer();
MessageDigest md = MessageDigest.getInstance("MD5");
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]));
}
}
You can also use Apache Commons Codec library.
This library includes methods public static String md5Hex(InputStream data) and public static String md5Hex(byte[] data) in the DigestUtils class.
No need to invent this yourself ;)
First you need to get the byte[] output of the MessageDigest:
byte[] bytes = hash.digest();
You can't easily print this though (with e.g. new String(bytes)) because it's going to contain binary that won't have good output representations. You can convert it to hex for display like this however:
StringBuilder sb = new StringBuilder(2 * bytes.length);
for (byte b : bytes) {
sb.append("0123456789ABCDEF".charAt((b & 0xF0) >> 4));
sb.append("0123456789ABCDEF".charAt((b & 0x0F)));
}
String hex = sb.toString();
Shortest way:
String toMD5(String input) {
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] raw = md.digest(input.getBytes());
return DatatypeConverter.printHexBinary(raw);
}
Just remember to handle the exception.
With the byte array, result from message digest:
...
byte hashgerado[] = md.digest(entrada);
...
for(byte b : hashgerado)
System.out.printf("%02x", Byte.toUnsignedInt(b));
Result (for example):
89e8a9f68ad3c4bba9b9d3581cf5201d
/**
* hashes:
* e7cfa2be5969e235138356a54bad7fc4
* 3c9ec110aa171b57bb41fc761130822c
*
* compiled with java 8 - 12 Dec 2015
*/
public static String generateHash() {
long r = new java.util.Random().nextLong();
String input = String.valueOf(r);
String md5 = null;
try {
java.security.MessageDigest digest = java.security.MessageDigest.getInstance("MD5");
//Update input string in message digest
digest.update(input.getBytes(), 0, input.length());
//Converts message digest value in base 16 (hex)
md5 = new java.math.BigInteger(1, digest.digest()).toString(16);
}
catch (java.security.NoSuchAlgorithmException e) {
e.printStackTrace();
}
return md5;
}
FYI...
In certain situations this did not work for me
md5 = new java.math.BigInteger(1, digest.digest()).toString(16);
but this did
StringBuilder sb = new StringBuilder();
for (int i = 0; i < digest.length; i++) {
if ((0xff & digest[i]) < 0x10) {
sb.append("0").append(Integer.toHexString((0xFF & digest[i])));
} else {
sb.append(Integer.toHexString(0xFF & digest[i]));
}
}
String result = sb.toString();
Call hash.digest() to finish the process. It will return an array of bytes.
You can create a String from a byte[] using a String constructor, however if you want a hex string you'll have to loop through the byte array manually and work out the characters.
This is another version of #anything answer:
StringBuilder sb = new StringBuilder();
for (int i = 0; i < digest.length; i++) {
if ((0xff & digest[i]) < 0x10) {
sb.append("0").append(Integer.toHexString((0xFF & digest[i])));
} else {
sb.append(Integer.toHexString(0xFF & digest[i]));
}
}
String result = sb.toString();
Related
I'm trying to hash data "text" to be transferred from Java Service to C# Service.
I'm using SHA256 as a Hashing algorithm, but despite the values and the salt being the same the result doesn't.
Here is my C# snippet
public string Sign(string textToHash, string salt){
byte[] convertedHash = new byte[salt.Length / 2];
for (int i = 0; i < salt.Length / 2; i++)
convertedHash[i] = (byte)int.Parse(salt.Substring(i * 2, 2), NumberStyles.HexNumber);
HMAC hasher = new HMACSHA256(convertedHash);
string hexHash = "";
using (hasher)
{
byte[] hashValue = hasher.ComputeHash(Encoding.UTF8.GetBytes(textToHash));
foreach (byte b in hashValue)
{
hexHash += b.ToString("X2");
}
}
return hexHash;
}
And, here is the Java snippet
public static String sign(String textToHash, String salt){
byte[] convertedHash = new byte[salt.length() / 2];
for (int i = 0; i < salt.length() / 2; i++)
{
convertedHash[i] = (byte)Integer.parseInt(salt.substring(i * 2, i * 2 + 2),16);
}
String hashedText = null;
try {
MessageDigest md = MessageDigest.getInstance("SHA-256");
md.update(convertedHash);
byte[] bytes = md.digest(textToHash.getBytes(StandardCharsets.UTF_8));
StringBuilder sb = new StringBuilder();
for (byte aByte : bytes) {
sb.append(Integer.toString((aByte & 0xff) + 0x100, 16).substring(1));
}
hashedText = sb.toString();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return hashedText;
}
In Java, I also tried
convertedHash = salt.getBytes();
But I got different results also.
Tests:
salt = ABCDEFG
text = hashme
Result in C#
70B38047C28FFEDCF7275C428E65310671CADB65F11A5C9A8CFBB3CF52112BA3
Result in Java
a8bc36606aade01591a1d12c8b3c87aca1fe55def79740def03a90b49f2c6b7c
So, any help about why the results aren't the same.
Thanks in advance.
To mimic the Java hashing, I used SHA256Managed rather than HMACSHA256 in C#
public static string Sign(string data, string salt)
{
UTF8Encoding encoder = new UTF8Encoding();
SHA256Managed sha256hasher = new SHA256Managed();
byte[] convertedHash = new byte[salt.Length / 2];
for (int i = 0; i < salt.Length / 2; i++)
convertedHash[i] = (byte)int.Parse(salt.Substring(i * 2, 2), NumberStyles.HexNumber);
byte[] dataBytes = encoder.GetBytes(data);
byte[] bytes = new byte[convertedHash.Length + dataBytes.Length];
Array.Copy(convertedHash, bytes, convertedHash.Length);
Array.Copy(dataBytes, 0, bytes, convertedHash.Length, dataBytes.Length);
byte[] hashedBytes = sha256hasher.ComputeHash(bytes);
return hashedBytes.Aggregate("", (current, t) => current + t.ToString("X2"));
}
HMACSHA256 is not a pure SHA-256.
Hi I'm using Bouncycastle library to create md5 hash from image byte array and client id string. But from Recognize.im API I'm still getting error invalid hash, is there anything wrong?
String myMd5(String myString, byte[] byteArray){
MD5Digest md5 = new MD5Digest();
md5.reset();
try {
md5.update(myString.getBytes("UTF-8"), 0 , myString.length());
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
md5.update(byteArray, 0, byteArray.length);
byte[] digest = new byte[md5.getDigestSize()];
md5.doFinal(digest, 0);
StringBuffer sb = new StringBuffer();
for (int i = 0; i < digest.length; ++i) {
sb.append(Integer.toHexString((digest[i] & 0xFF) | 0x100)
.substring(1, 3));
}
return sb.toString();
}
I am using same MySQL table to store password from different program. One is written in Java and another is written in PHP.
I am saving password via PHP using this script:
encrypted_password= md5(md5('added_salt').md5(md5('plain_password')));
I need to encrypt password in Java using MD5 and salt like above. I write code in Java but it's output is different:
MessageDigest md = MessageDigest.getInstance("MD5");
String salts = "a,d,d,e,d,_,s,a,l,t";
String salttmps[] = salts.split(",");
byte salt[] = new byte[salttmps.length];
for (int i = 0; i < salt.length; i++) {
salt[i] = Byte.parseByte(salttmps[i]);
}
md.update(salt);
md.update(password.getBytes());
byte byteData[] = md.digest();
StringBuffer sb = new StringBuffer();
for (int i = 0; i < byteData.length; i++) {
sb.append(Integer.toString((byteData[i] & 0xff) + 0x100, 16).substring(1));
}
password = sb.toString();
I need to correct Java code and generate output same as PHP.
If you could post an example of output in your question, it would be better to reproduce the algorithm.
I guess you should do something like this:
public static void main(String[] args) {
try {
System.out.println(md5(md5("added_salt"), md5("plain_password")));
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
public static String md5(String plainText) throws NoSuchAlgorithmException {
return md5(null, plainText);
}
public static String md5(String salt, String plainText)
throws NoSuchAlgorithmException {
MessageDigest md = MessageDigest.getInstance("MD5");
if (salt != null) {
md.update(salt.getBytes());
}
md.update(plainText.getBytes());
byte byteData[] = md.digest();
StringBuffer sb = new StringBuffer();
for (int i = 0; i < byteData.length; i++) {
sb.append(Integer.toString((byteData[i] & 0xff) + 0x100, 16)
.substring(1));
}
return sb.toString();
}
md5(md5("added_salt"), md5("plain_password")) returns 3bd9e544ab1a3d3485f07af38cc1b415
I am trying to convert a String to its MD5 representation with this code:
public static void main(String[] args) throws NoSuchAlgorithmException {
String s = "oshai";
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(s.getBytes(),0,s.length());
String md5 = new BigInteger(1,m.digest()).toString(16);
System.out.println(md5.length());
}
The returned String has add number of digits (31, so it can be an Hex number). What am I doing wrong?
You don't want to use BigInteger. Try a more traditional toHexString method..
public static void main(String[] args) throws NoSuchAlgorithmException {
String s = "oshai";
MessageDigest m = MessageDigest.getInstance("MD5");
m.update(s.getBytes(),0,s.length());
String string = toHexString(m.digest());
System.out.println(string);
}
public static String toHexString(byte[] bytes) {
StringBuilder sb = new StringBuilder();
for(byte b : bytes) {
sb.append(String.format("%02x", b));
}
return sb.toString();
}
This method works for sure:
private String hashWithMD5(String text) throws UnsupportedEncodingException, NoSuchAlgorithmException {
MessageDigest messageDigest = MessageDigest.getInstance("MD5");
byte[] digest = messageDigest.digest(text.getBytes("UTF-8"));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < digest.length; i++) {
sb.append(Integer.toString((digest[i] & 0xff) + 0x100, 16).substring(1));
}
return sb.toString();
}
I have faced an error with missing "00" at the left side, while converting string to the encrypted format.
Normally you won't find the bug in your app by using the common md5 method.
So, please test your app with the string "sandeep" (I have used it because it has a "00" at left side).
This issue messed my hours and finally i found the following solution from a link.
"I had an error with md5 string with 00 at leftside, ie, a string “sandeep” converted to “DCF16D903E5890AABA465B0B1BA51F ” than the actual “00DCF16D903E5890AABA465B0B1BA51F
I ended up with this method, that work cool in my app."
public static String md5(String inputString) {
try {
// Create MD5 Hash
MessageDigest msgDigest = java.security.MessageDigest.getInstance("MD5");
msgDigest.update(inputString.getBytes());
byte msgDigestBytes[] = msgDigest.digest();
// Create Hex String
StringBuffer hexString = new StringBuffer();
for (int i = 0; i < msgDigestBytes.length; i++) {
String h = Integer.toHexString(0xFF & msgDigestBytes[i]);
while (h.length() < 2)
h = "0" + h;
hexString.append(h);
}
return hexString.toString();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return "";
}
Ref:http://www.coderexception.com/CbHuB1uHPWxXUQXi/converting-string-to-md5-gives-add-number-of-digits
use this method :
public static String md5(String input) {
String md5 = null;
if (null == input)
return null;
try {
// Create MessageDigest object for MD5
MessageDigest digest = MessageDigest.getInstance("MD5");
// Update input string in message digest
digest.update(input.getBytes(), 0, input.length());
// Converts message digest value in base 16 (hex)
md5 = new BigInteger(1, digest.digest()).toString(16);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return md5;
}
I am using following code block to generate MD5 hashes:
public static String encode(String data) throws Exception {
/* Check the validity of data */
if (data == null || data.isEmpty()) {
throw new IllegalArgumentException("Null value provided for "
+ "MD5 Encoding");
}
/* Get the instances for a given digest scheme MD5 or SHA */
MessageDigest m = MessageDigest.getInstance("MD5");
/* Generate the digest. Pass in the text as bytes, length to the
* bytes(offset) to be hashed; for full string pass 0 to text.length()
*/
m.update(data.getBytes(), 0, data.length());
/* Get the String representation of hash bytes, create a big integer
* out of bytes then convert it into hex value (16 as input to
* toString method)
*/
String digest = new BigInteger(1, m.digest()).toString(16);
return digest;
}
When I run the above code segment with String data as [12, B006GQIIEM, MH-ANT2000], the output is a 31 character hash - 268d43a823933c9dafaa4ac0e756d6a.
Is there any problem with the MD5 hash function or there is some problem in the code above?
The only issue in your code is when MSB is less than Ox10, the result hash string will only have 31 bytes, instead of 32 bytes, missing the leading zero.
Create your md5 string in this way:
byte messageDigest[] = m.digest();
hexString = new StringBuffer();
for (int i=0;i<messageDigest.length;i++) {
String hex=Integer.toHexString(0xFF & messageDigest[i]);
if(hex.length()==1)
hexString.append('0');
hexString.append(hex);
}
You can try this:
...
String digest = String.format("%032x", new BigInteger(1, m.digest()));
Note: it is "%032x", not "%32x".
This is how I use MD5 hash. Calculate MD5 hash from string and return 32-byte hexadecimal representation.
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class MySimpleMD5 {
private static String convertToHex(byte[] data) {
StringBuffer buf = new StringBuffer();
for (int i = 0; i < data.length; i++) {
int halfbyte = (data[i] >>> 4) & 0x0F;
int two_halfs = 0;
do {
if ((0 <= halfbyte) && (halfbyte <= 9))
buf.append((char) ('0' + halfbyte));
else
buf.append((char) ('a' + (halfbyte - 10)));
halfbyte = data[i] & 0x0F;
} while(two_halfs++ < 1);
}
return buf.toString();
}
public static String MD5(String text)
throws NoSuchAlgorithmException, UnsupportedEncodingException {
MessageDigest md;
md = MessageDigest.getInstance("MD5");
byte[] md5hash = new byte[32];
md.update(text.getBytes("iso-8859-1"), 0, text.length());
md5hash = md.digest();
return convertToHex(md5hash);
}
}
You can also try this:
private static String getMd5Hash(String input) throws NoSuchAlgorithmException {
MessageDigest m = MessageDigest.getInstance("MD5");
byte[] data = m.digest(EncodingUtils.getBytes(input, "UTF8"));
StringBuilder sBuilder = new StringBuilder();
for (int i = 0; i < data.length; i++) {
for (byte b : data) {
if(b == 0x00){
sBuilder.append("00");
} else if ((b & 0x0F) == b) {
sBuilder.append("0");
break;
} else {
break;
}
}
BigInteger bigInt = new BigInteger(1, data);
sBuilder.append(bigInt.toString(16));
}
// Return the hexadecimal string.
return sBuilder.toString().substring(0, 32);
}