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MessageDigest in Java to C#

I am trying to translate java code to c#. I'm kind of stuck on this exercise below:
MessageDigest md = MessageDigest.getInstance("MD5");
md.reset();
md.update(pass.getBytes());
byte[] enc = md.digest();
StringBuilder hex = new StringBuilder();
for (int i = 0; i < enc.length; i++) {
String h = Integer.toHexString(0xFF & enc[i]);
hex.append((h.length() == 2) ? h : ("0" + h));
}
This is what I have tried but I am not getting the desired result which would be the following string: "e81e26d88d62aba9ab55b632f25f117d"
My Code:
using System.Security.Cryptography;
using System.Text;
string user_password = "HELLOWORLD";
byte[] hashBytes = Encoding.UTF8.GetBytes(user_password);
SHA1 sha1 = SHA1Managed.Create();
byte[] cryptPassword = sha1.ComputeHash(hashBytes);
user_password = Encoding.Default.GetString(cryptPassword);
StringBuilder hex = new StringBuilder();
for (int i = 0; i < cryptPassword.Length; i++)
{
// Store integer 182
int intValue = cryptPassword[i];
// Convert integer 182 as a hex in a string variable
string hexValue = intValue.ToString("X");
// Convert the hex string back to the number
int intAgain = int.Parse(hexValue, System.Globalization.NumberStyles.HexNumber);
hex.Append((intAgain.ToString().Length == 2) ? intAgain : ("0" + intAgain.ToString()));
}
Console.WriteLine("pass: " + hex.ToString());
Does anyone know the answer?

Main issue is you are using SHA1 function instead of MD5. Also Im not sure why you are looping over the password length. Every MD5 hash will be the same length regardless of input size.
using System;
using System.Security.Cryptography;
using System.Text;
string user_password = "HELLOWORLD";
byte[] hashBytes = Encoding.UTF8.GetBytes(user_password);
var md5 = MD5.Create();
var hash = md5.ComputeHash(hashBytes);
StringBuilder hex = new StringBuilder();
foreach (byte b in hash)
hex.AppendFormat("{0:x2}", b);
Console.WriteLine("pass: " + hex);
return ;

Mismatch in result when encrypting in AES for Java and Golang

I'm using this code in Java to generate the cipher text using simple AES algorithm:
public String encrypt(String message, String key) {
skeySpec = new SecretKeySpec(HexUtil.HexfromString(key), "AES");
cipher = Cipher.getInstance("AES");
cipher.init(1, skeySpec);
byte encstr[] = cipher.doFinal(message.getBytes());
return HexUtil.HextoString(encstr);
}
And the function HexfromString is:
public static byte[] HexfromString(String s) {
int i = s.length();
byte[] byte0 = new byte[(i + 1) / 2];
int j = 0;
int k = 0;
if (i % 2 == 1) byte0[k++] = (byte) HexfromDigit(s.charAt(j++));
while (j < i) {
int v1 = HexfromDigit(s.charAt(j++)) << 4;
int v2 = HexfromDigit(s.charAt(j++));
byte0[k++] = (byte) (v1 | v2);
}
return byte0;
}
I wrote the following code in Golang to mimic the above result.
func EncryptAES(secretKey string, plaintext string) string {
key := hex.DecodeString(secretKey)
c, err := aes.NewCipher(key)
CheckError(err)
out := make([]byte, len(plaintext))
c.Encrypt(out, []byte(plaintext))
return hex.EncodeToString(out)
}
But the issue is that the []bytes key returned from hex.DecodeString() is in unsigned Int where as in Java, the result is in signed Int. And obviously, the encrypted text results are also different, even though every input is same.

Java 256-bit AES Encryption

I need to implement 256 bit AES encryption for cash flow i have c# answer but the answer is not the same,for a newbie, I am not sure if my direction is correct.
this is my code
public static void main(String[] args) {
String key = "12345678901234567890123456789012";
String hashIv = "1234567890123456";
String value = "MerchantID=3430112RespondType=JSONTimeStamp=1485232229Version=1.4MerchantOrderNo=S_1485232229Amt=40ItemDesc=UnitTest";
String result = encrypt(key, hashIv, value);
System.out.println(result);
System.out.println();
String sha256 = encrySha256("HashKey=" + key + "&" + result + "&HashIV=" + hashIv);
System.out.println(sha256.trim());
}
public static String encrypt(String hashKey, String hashIv, String text) {
try {
SecretKeySpec skeySpec = new SecretKeySpec(hashKey.getBytes("UTF-8"), "AES");
IvParameterSpec ivParameterSpec = new IvParameterSpec(hashIv.getBytes("UTF-8"));
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivParameterSpec);
byte[] encrypted = cipher.doFinal((text.getBytes("UTF-8")));
String test = bytesToHex(encrypted);
return test.toLowerCase();
} catch (Exception e) {
System.out.println(e.getMessage());
}
return null;
}
public static String bytesToHex(byte[] bytes) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < bytes.length; i++) {
String hex = Integer.toHexString(bytes[i] & 0xFF);
if (hex.length() == 1) {
hex = '0' + hex;
}
sb.append(hex.toUpperCase());
}
return sb.toString();
}
public static String encrySha256(String value) {
try {
MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
messageDigest.update(value.getBytes());
byte byteBuffer[] = messageDigest.digest();
StringBuffer strHexString = new StringBuffer();
for (int i = 0; i < byteBuffer.length; i++) {
String hex = Integer.toHexString(0xff & byteBuffer[i]);
if (hex.length() == 1) {
strHexString.append('0');
}
strHexString.append(hex);
}
return strHexString.toString().toUpperCase();
} catch (Exception e) {
}
return null;
}
sample encrypt answer :
ff91c8aa01379e4de621a44e5f11f72e4d25bdb1a18242db6cef9ef07d80b0165e476fd1d
9acaa53170272c82d122961e1a0700a7427cfa1cf90db7f6d6593bbc93102a4d4b9b66d9
974c13c31a7ab4bba1d4e0790f0cbbbd7ad64c6d3c8012a601ceaa808bff70f94a8efa5a4f
984b9d41304ffd879612177c622f75f4214fa
encryptSha256 answer : EA0A6CC37F40C1EA5692E7CBB8AE097653DF3E91365E6A9CD7E91312413C7BB8
this is c# code and this is sample data
[MerchantID] => 3430112 [RespondType] => JSON [TimeStamp] => 1485232229
[Version] => 1.4 [MerchantOrderNo] => S_1485232229 [Amt] => 40 [ItemDesc] =>
UnitTest
public string EncryptAES256(string source)//加密
{
string sSecretKey = "12345678901234567890123456789012";
string iv = "1234567890123456";
byte[] sourceBytes =
AddPKCS7Padding(Encoding.UTF8.GetBytes(source), 32);
var aes = new RijndaelManaged();
aes.Key = Encoding.UTF8.GetBytes(sSecretKey);
aes.IV = Encoding.UTF8.GetBytes(iv);
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.None;
ICryptoTransform transform = aes.CreateEncryptor();
return ByteArrayToHex(transform.TransformFinalBlock(sourceBytes, 0,
sourceBytes.Length)).ToLower();
}
private static byte[] AddPKCS7Padding(byte[] data, int iBlockSize)
{
int iLength = data.Length;
byte cPadding = (byte)(iBlockSize - (iLength % iBlockSize));
var output = new byte[iLength + cPadding];
Buffer.BlockCopy(data, 0, output, 0, iLength);
for (var i = iLength; i < output.Length; i++)
output[i] = (byte)cPadding;
return output;
}
private static string ByteArrayToHex(byte[] barray)
{
char[] c = new char[barray.Length * 2];
byte b;
for (int i = 0; i < barray.Length; ++i)
{
b = ((byte)(barray[i] >> 4));
c[i * 2] = (char)(b > 9 ? b + 0x37 : b + 0x30);
b = ((byte)(barray[i] & 0xF));
c[i * 2 + 1] = (char)(b > 9 ? b + 0x37 : b + 0x30);
}
return new string(c);
}

The reason for the different encrypted data is that you compare different plain texts. In your Java code you encrypt the plain text
MerchantID=3430112RespondType=JSONTimeStamp=1485232229Version=1.4MerchantOrderNo=S_1485232229Amt=40ItemDesc=UnitTest
and you compare the encrypted data with your reference data
ff91c8aa01379e4de621a44e5f11f72e4d25bdb1a18242db6cef9ef07d80b0165e476fd1d9acaa53170272c82d122961e1a0700a7427cfa1cf90db7f6d6593bbc93102a4d4b9b66d9974c13c31a7ab4bba1d4e0790f0cbbbd7ad64c6d3c8012a601ceaa808bff70f94a8efa5a4f984b9d41304ffd879612177c622f75f4214fa
However, these reference data correspond to a different plain text. The latter you can easily derive by decrypting the reference data with the C# DecryptAES256-method which provides
MerchantID=3430112&RespondType=JSON&TimeStamp=1485232229&Version=1.4&MerchantOrderNo=S_1485232229&Amt=40&ItemDesc=UnitTest
Here, in contrast to the plain text in your Java code, a &-delimiter is used.
If you use the same plain text the Java encrypt- and the C# EncryptAES256-method provide the same encrypted data (same key, IV and padding supposed; for the latter see EDIT-section).
In the following testcase the plain text from your Java code is used:
encrypt("12345678901234567890123456789012", "1234567890123456", "MerchantID=3430112RespondType=JSONTimeStamp=1485232229Version=1.4MerchantOrderNo=S_1485232229Amt=40ItemDesc=UnitTest")
and
EncryptAES256("MerchantID=3430112RespondType=JSONTimeStamp=1485232229Version=1.4MerchantOrderNo=S_1485232229Amt=40ItemDesc=UnitTest")
both provide the encrypted data:
ff91c8aa01379e4de621a44e5f11f72ef45b7b9f9663d386da51af13f7f3b8f2b1ed4a3b7ac6b7783402193ea1d766e3046b6acf612d62568ccdbc475e5a14d114273735b069464dcc8281f4e5bf8486eb97d31602c3fe79cfe7140d2848413edad9d96fabf54d103f3d7a9b401c83fa5e4f17b10a280df10b3d61f23e69bbb8
which (as expected) differs from your reference data (with the exception of the first block).
EDIT
There is a second issue concerning the padding: Your C# EncryptAES256-method uses a custom padding provided by the C# AddPKCS7Padding-method which pads to a multiple of 32 bytes.
In contrast, your Java encrypt-method uses PKCS5Padding which pads to a multiple of 16 bytes.
Thus, the encrypted data of the Java encrypt- and the C# EncryptAES256-method differ if the length of the plain text is between 16 * n byte and 16 * (n + 1) - 1 byte with even n (0,2,4,...).
For odd n (1,3,5,...) the encrypted data are identical. In the example above the byte array of the plain text has 116 bytes that is n = 7 (112 <= 116 <= 127) and therefore the encrypted data are the same.
If the Java encrypt-method should use the same padding as the C# EncryptAES256-method you additionally have to implement an analogous Java-method e.g.:
private static byte[] addPKCS7Padding(byte[] data, int iBlockSize)
{
int iLength = data.length;
byte cPadding = (byte)(iBlockSize - (iLength % iBlockSize));
byte[] output = new byte[iLength + cPadding];
System.arraycopy(data, 0, output, 0, iLength);
for (int i = iLength; i < output.length; i++)
output[i] = (byte)cPadding;
return output;
}
and in the Java encrypt-method you have to replace:
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
with
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
and also
byte[] encrypted = cipher.doFinal(text.getBytes("UTF-8"));
with
byte[] encrypted = cipher.doFinal(addPKCS7Padding(text.getBytes("UTF-8"), 32));

before:
MerchantID=3430112RespondType=JSONTimeStamp=1485232229Version=1.4MerchantOrderNo=S_1485232229Amt=40ItemDesc=UnitTest
After:
MerchantID=3430112&RespondType=JSON&TimeStamp=1485232229&Version=1.4&MerchantOrderNo=S_1485232229&Amt=40&ItemDesc=UnitTest
I only add "&" with each parameter, it's work!!!!
try it!!!
(我只加了&就成功拉，你的代碼沒問題，只是參數要加&而已)

SHA-512 hashing with Android

I was wondering if I can SHA-512 hash a string on Android Studio without a salt.
I've seen other questions, but they all involve the salt, but I want something like this:
TestBox.text = sha512("Hello, world!");
And TextBox will read c1527cd893c124773d811911970c8fe6e857d6df5dc9226bd8a160614c0cd963a4ddea2b94bb7d36021ef9d865d5cea294a82dd49a0bb269f51f6e7a57f79421;

The other questions you saw use salt so just don't use salt like so:
MessageDigest md = MessageDigest.getInstance("SHA-512");
byte[] digest = md.digest("Hello, world!".getBytes());
StringBuilder sb = new StringBuilder();
for (int i = 0; i < digest.length; i++) {
sb.append(Integer.toString((digest[i] & 0xff) + 0x100, 16).substring(1));
}
System.out.println(sb);
Based on this answer.

Keds example is right, but .length will always be biger than 32, (127) so more correct answer should be
private fun getSHA512(input:String):String{
val md: MessageDigest = MessageDigest.getInstance("SHA-512")
val messageDigest = md.digest(input.toByteArray())
// Convert byte array into signum representation
val no = BigInteger(1, messageDigest)
// Convert message digest into hex value
var hashtext: String = no.toString(16)
// Add preceding 0s to make it 128 chars long
while (hashtext.length < 128) {
hashtext = "0$hashtext"
}
// return the HashText
return hashtext
}

method for calculating sha-512 in kotlin
fun getSHA256(input:String):String{
return MessageDigest
.getInstance("SHA-256")
.digest(input.toByteArray())
.fold("") { str, it -> str + "%02x".format(it) }
}

A more functional solution:
fun sha512(input: String): String {
return MessageDigest.getInstance("SHA-512")
.digest(input.toByteArray())
.joinToString(separator = "") {
((it.toInt() and 0xff) + 0x100)
.toString(16)
.substring(1)
}
}

I guess the equivalent in Kotlin is:
fun encriptar(cadena: String): String {
var md: MessageDigest = MessageDigest.getInstance("SHA-512")
var digest = md.digest(cadena.toByteArray())
var sb: StringBuilder = StringBuilder()
var i = 0
while (i < digest.count()) {
sb.append(((digest[i] and 0xff.toByte()) + 0x100).toString(16).substring(0, 1))
i++
}
return sb.toString()
}

MD5 hash in android or java

I required to convert string in MD5 hash.
I am using
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] thedigest = md.digest(bytesOfMessage);
final protected static char[] hexArray = "0123456789ABCDEF".toCharArray();
public static String bytesToHex( byte[] bytes )
{
char[] hexChars = new char[ bytes.length * 2 ];
for( int j = 0; j < bytes.length; j++ )
{
int v = bytes[ j ] & 0xFF;
hexChars[ j * 2 ] = hexArray[ v >>> 4 ];
hexChars[ j * 2 + 1 ] = hexArray[ v & 0x0F ];
}
return new String( hexChars );
}
It is giving output like this website http://www.md5.cz/
but I required to generate hash as this http://webcodertools.com/hashstring giving output.
Please use test in both sites.
with using above function I am getting o/p like first site but I need as second site is giving.
Is there any different function or am I missing something in this?
Thanks.

The second web site is simply using base64 instead of hex to represent the binary data as text. So you can get rid of your bytesToHex method entirely, and just use Base64:
String base64Digest = Base64.encodeToString(thedigest, Base64.DEFAULT);
(As an aside, I'd avoid using the as a prefix in variable names - it provides no benefit, and is just cruft.)

Use this method it will return in the same format
public static String getMd5Hash(String input) {
try {
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] messageDigest = md.digest(input.getBytes());
BigInteger number = new BigInteger(1, messageDigest);
String md5 = number.toString(16);
while (md5.length() < 32)
md5 = "0" + md5;
return md5;
} catch (NoSuchAlgorithmException e) {
Log.e("MD5", e.getLocalizedMessage());
return null;
}
}
This returns in //4a2028eceac5e1f4d252ea13c71ecec6 format MD5 of "WHAT" and
String base64format = Base64.encodeToString(thedigest, Base64.DEFAULT); //as given by #Jon Skeet
will return in the format as SiAo7OrF4fTSUuoTxx7Oxg==
Sorry for vice-versa solution.