I have an encrypted string in visual basic. NET 2008, the functions to encrypt and decrypt are the following:
Imports System.Security.Cryptography
Public Shared Function Encriptar(ByVal strValor As String) As String
Dim strEncrKey As String = "key12345"
Dim byKey() As Byte = {}
Dim IV() As Byte = {&H12, &H34, &H56, &H78, &H90, &HAB, &HCD, &HEF}
Try
byKey = System.Text.Encoding.UTF8.GetBytes(strEncrKey)
Dim des As New DESCryptoServiceProvider
Dim inputByteArray() As Byte = Encoding.UTF8.GetBytes(strValor)
Dim ms As New MemoryStream
Dim cs As New CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write)
cs.Write(inputByteArray, 0, inputByteArray.Length)
cs.FlushFinalBlock()
Return Convert.ToBase64String(ms.ToArray())
Catch ex As Exception
Return ""
End Try
End Function
Public Shared Function Desencriptar(ByVal strValor As String) As String
Dim sDecrKey As String = "key12345"
Dim byKey() As Byte = {}
Dim IV() As Byte = {&H12, &H34, &H56, &H78, &H90, &HAB, &HCD, &HEF}
Dim inputByteArray(strValor.Length) As Byte
Try
byKey = System.Text.Encoding.UTF8.GetBytes(sDecrKey)
Dim des As New DESCryptoServiceProvider
If Trim(strValor).Length = 0 Then
Throw New Exception("Password No debe estar en Blanco")
End If
inputByteArray = Convert.FromBase64String(strValor)
Dim ms As New MemoryStream
Dim cs As New CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write)
cs.Write(inputByteArray, 0, inputByteArray.Length)
cs.FlushFinalBlock()
Dim encoding As System.Text.Encoding = System.Text.Encoding.UTF8
Return encoding.GetString(ms.ToArray(), 0, ms.ToArray.Count)
Catch ex As Exception
Return ""
End Try
End Function
for example the word "android" encrypted with this function gives me the result "B3xogi/Qfsc="
now I need to decrypt the string "B3xogi/Qfsc=" it from java, by the same key, which is "key12345", and the result should be "android"...anyone know how to do this?
Thanks in advance.
Using Apache Commons Codec for hex and base64 encoding/decoding, you can use the following code:
KeySpec ks = new DESKeySpec("key12345".getBytes("UTF-8"));
SecretKey key = SecretKeyFactory.getInstance("DES").generateSecret(ks);
IvParameterSpec iv = new IvParameterSpec(
Hex.decodeHex("1234567890ABCDEF".toCharArray()));
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, iv);
byte[] decoded = cipher.doFinal(Base64.decodeBase64("B3xogi/Qfsc="));
System.out.println("Decoded: " + new String(decoded, "UTF-8"));
You're using DES encryption.
Here is an example on how to encrypt and decrypt with DES.
The main point is to create a SecretKey, a Cipher using it, and decrypt your String with it.
Mmmh...
I found another article that may best suit your question, because it uses IVBytes :)
public String encryptText(String cipherText) throws Exception {
String plainKey = "key12345";
String plainIV = "1234567890ABCDEF";
KeySpec ks = new DESKeySpec(plainKey.getBytes(encodingType));
SecretKey key = SecretKeyFactory.getInstance(keyDes).generateSecret(ks);
IvParameterSpec iv = new IvParameterSpec(
org.apache.commons.codec.binary.Hex.decodeHex(plainIV.toCharArray()));
Cipher cipher = Cipher.getInstance(encryptAlgo);
cipher.init(Cipher.ENCRYPT_MODE, key, iv);
byte[] decoded = cipher.doFinal(cipherText.getBytes(encodingType));
return new Base64().encodeToString(decoded);
}
The closest Java classes to .NET's CryptoStream class are the CipherInputStream and CipherOutputStream classes.
Related
I trying to implement this same code to encrypt on c# but always i get some different encrypted code :
This is my Java class :
public class AES256 {
private static final String SECRET_KEY = "my_super_secret_key_ho_ho_ho";
private static final String SALT = "ssshhhhhhhhhhh!!!!";
public static String encrypt(String strToEncrypt) {
try {
byte[] iv = "1234567891234567".getBytes("UTF-8");
IvParameterSpec ivspec = new IvParameterSpec(iv);
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
KeySpec spec = new PBEKeySpec(SECRET_KEY.toCharArray(), SALT.getBytes(), 65536, 256);
SecretKey tmp = factory.generateSecret(spec);
SecretKeySpec secretKey = new SecretKeySpec(tmp.getEncoded(), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivspec);
return Base64.getEncoder()
.encodeToString(cipher.doFinal(strToEncrypt.getBytes(StandardCharsets.UTF_8)));
} catch (Exception e) {
System.out.println("Error while encrypting: " + e.toString());
}
return null;
}
}
How can i implement the same on c#? i usig this as a model -> c# AES Encrypt but the result is diffetent even using the same secret , salt ,interaction hash count
This what i have on c# :
var passPhrase = "my_super_secret_key_ho_ho_ho";
// Initialization Vector (16 bit length)
var iv = "1234567891234567";
// Encrypt & Decrypt (with advanced settings)
var opts = new AESCryptOptions()
{
PasswordHash = AESPasswordHash.SHA1,
PasswordHashIterations = 65536,
PasswordHashSalt = "ssshhhhhhhhhhh!!!!",
PaddingMode = PaddingMode.PKCS7,
MinSaltLength = 4,
MaxSaltLength = 16,
FixedKeySize=256
};
var encryptedText = new AESCrypt(passPhrase, iv, opts).Encrypt(text);
And the encrypt Method, i changed the hash to sha256, the only change made from the implement from gitHub:
PasswordDeriveBytes password = new PasswordDeriveBytes(
passPhrase,
saltValueBytes,
("SHA256"),
Options.PasswordHashIterations);
// Convert key to a byte array adjusting the size from bits to bytes.
keyBytes = password.GetBytes(keySize / 8);
I'm currently running into an issue where our decryption portion of our C# site is having trouble with the padding with the encrypted string from java. The .Net code throws this error "Padding is invalid and cannot be removed". The _signKey and _encKey are both 64 bytes.
public String encryptString(String plainText) {
byte[] ciphertext;
byte[] iv = new byte[16];
byte[] plainBytes = plainText.getBytes(StandardCharsets.UTF_8);
String _signKey = "****************************************************************";
String _encKey = "****************************************************************";
try {
Mac sha256 = Mac.getInstance("HmacSHA256");
SecretKeySpec shaKS = new SecretKeySpec(_signKey.getBytes(StandardCharsets.UTF_8), "HmacSHA256");
sha256.init(shaKS);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
SecureRandom randomSecureRandom = SecureRandom.getInstance("SHA1PRNG");
iv = new byte[cipher.getBlockSize()];
randomSecureRandom.nextBytes(iv);
IvParameterSpec ivParams = new IvParameterSpec(iv);
byte[] sessionKey = sha256.doFinal((_encKey + iv).getBytes(StandardCharsets.UTF_8));
// Perform Encryption
SecretKeySpec eks = new SecretKeySpec(sessionKey, "AES");
cipher.init(Cipher.ENCRYPT_MODE, eks, ivParams);
ciphertext = cipher.doFinal(plainBytes);
System.out.println("ciphertext= " + new String(ciphertext));
// Perform HMAC using SHA-256 on ciphertext
SecretKeySpec hks = new SecretKeySpec(_signKey.getBytes(StandardCharsets.UTF_8), "HmacSHA256");
Mac mac = Mac.getInstance("HmacSHA256");
mac.init(hks);
ByteArrayOutputStream outputStream2 = new ByteArrayOutputStream();
outputStream2.write(iv);
outputStream2.write(ciphertext);
outputStream2.flush();
outputStream2.write(mac.doFinal(outputStream2.toByteArray()));
return Base64.encodeBase64String(outputStream2.toByteArray());
} catch (Exception e) {
e.printStackTrace();
}
return plainText;
}
Does does encrypt the string properly as far as I can tell. We cannot change any code on the .Net side to decrypt this because this is being used today.
public static string DecryptString(string ciphertext)
{
using (HMACSHA256 sha256 = new HMACSHA256(Encoding.UTF8.GetBytes(_signKey)))
{
// Convert message to bytes
byte[] encBytes = Convert.FromBase64String(ciphertext);
// Get arrays for comparing HMAC tags
byte[] sentTag = new byte[sha256.HashSize / 8];
byte[] calcTag = sha256.ComputeHash(encBytes, 0, (encBytes.Length - sentTag.Length));
// If message length is too small return null
if (encBytes.Length < sentTag.Length + _ivLength) { return null; }
// Copy tag from end of encrypted message
Array.Copy(encBytes, (encBytes.Length - sentTag.Length), sentTag, 0, sentTag.Length);
// Compare tags with constant time comparison, return null if no match
int compare = 0;
for (int i = 0; i < sentTag.Length; i++) { compare |= sentTag[i] ^ calcTag[i]; }
if (compare != 0) { return null; }
using (AesCryptoServiceProvider csp = new AesCryptoServiceProvider())
{
// Set parameters
csp.BlockSize = _blockBits;
csp.KeySize = _keyBits;
csp.Mode = CipherMode.CBC;
csp.Padding = PaddingMode.PKCS7;
// Copy init vector from message
var iv = new byte[_ivLength];
Array.Copy(encBytes, 0, iv, 0, iv.Length);
// Derive session key
byte[] sessionKey = sha256.ComputeHash(Encoding.UTF8.GetBytes(_encKey + iv));
// Decrypt message
using (ICryptoTransform decrypt = csp.CreateDecryptor(sessionKey, iv))
{
return Encoding.UTF8.GetString(decrypt.TransformFinalBlock(encBytes, iv.Length, encBytes.Length - iv.Length - sentTag.Length));
}
}
}
}
If there is anything that sticks out it would be appreciated for the reply.
I didn't read all your code, but this line in Java:
byte[] sessionKey = sha256.doFinal((_encKey + iv).getBytes(StandardCharsets.UTF_8));
does nothing useful or sensible. The "+" operator does string concatenation, but iv is a byte[], not a String. So java uses iv.toString(), which simply returns a String containing something like [B#1188e820 which is meaningless in this context.
Refer four java code and DotNet code:
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding"); //Java
csp.Padding = PaddingMode.PKCS7; //.Net
You are essentially using different padding, that is the probable source of error; however, there is an alternate view, Refer this great post and this for general fundamentals on padding
The cipher suites supported by deafult Oracle JVM implementation are here
If you notice it does not have 'AES/CBC/PKCS7Padding', a PKCS#7 padding implementation is available in sun.security package, refer this, otherwise you could use Bouncy Castle packages. It would be recommendable to use Bouncy Castle as com.sun package are generally considered unsupported.
I have a reference of PHP code that does Rijndael encryption. I want convert it to java code, I tried few examples but none of them worked for me.
Here is the php code:
$initialisationVector = hash("sha256", utf8_encode($myiv), TRUE);
$key = hash("sha256", utf8_encode($mykey), TRUE);
$encryptedValue = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256,$encryptKey, utf8_encode($mydata), MCRYPT_MODE_CBC, $initialisationVector));
Here is my java code that throws: Key length not 128/160/192/224/256 bits
public static String encrypt() throws Exception{
String myiv = "somevalue";
String mykey = "somevalue";
String mydata = "somevalue";
String new_text = "";
RijndaelEngine rijndael = new RijndaelEngine(256);
CBCBlockCipher cbc_rijndael = new CBCBlockCipher(rijndael);
ZeroBytePadding c = new ZeroBytePadding();
PaddedBufferedBlockCipher pbbc = new PaddedBufferedBlockCipher(cbc_rijndael, c);
byte[] iv_byte = sha256(myiv);
byte[] givenKey = sha256(mykey);
CipherParameters keyWithIV = new ParametersWithIV(new KeyParameter(givenKey), iv_byte);
pbbc.init(true, keyWithIV);
byte[] plaintext = mydata.getBytes(Charset.forName("UTF-8"));
byte[] ciphertext = new byte[pbbc.getOutputSize(plaintext.length)];
int offset = 0;
offset += pbbc.processBytes(plaintext, 0, plaintext.length, ciphertext, offset);
offset += pbbc.doFinal(ciphertext, offset);
new_text = new String(new Base64().encode(ciphertext), Charset.forName("UTF-8"));
System.out.println(new_text);
return new_text;
}
public static byte[] sha256(String input) throws NoSuchAlgorithmException {
MessageDigest md = MessageDigest.getInstance("SHA-256");
byte[] messageDigest = md.digest(input.getBytes(Charset.forName("UTF-8")));
return messageDigest;
}
I am not really good with cryptography. Thanks in advance!
The error message is clear: "initialisation vector must be the same length as block size". You are specifiying a 256-bit (32-byte) block size, verify that iv_byte is 32-bytes.
There are a few problems:
For the IV get the bytes from the hash, pass the bytes to the encryption function, BigInteger has no place in that.
sha256(appId) provides a 256-bit key, just use it.
The following are not needed, the result of sha256 is 256-bits:
final int keysize = 256;
byte[] keyData = new byte[keysize];
System.arraycopy(givenKey, 0, keyData, 0, Math.min(givenKey.length, keyData.length));
sha256(appId) provides a 256-bit key, just use it.
The following are not needed:
final int keysize = 256;
byte[] keyData = new byte[keysize];
System.arraycopy(givenKey, 0, keyData, 0, Math.min(givenKey.length, keyData.length));
mcrypt "MCRYPT_RIJNDAEL_256" is specifying a 256-bit block size which means it is not AES, "MCRYPT_RIJNDAEL_128" is AES which should be used.
mcrypt uses non-standard null padding, that needs to be accommodated.
Using a SHA-256 hash is not sufficiently secure, use a password derivation function such as PBKDF2.
We are facing an issue while trying to Encrypt data in Android and Decrypt it in a WCF Service. The Android code to encrypt data is as follows:
try{
String strModulus = "tr82UfeGetV7yBKcOPjFTWs7pHqqr/5YKKWMUZ/HG4HnCmWrZsOhuR1FBnMZ/g2YiosoSlu0zd7Ukz9lX7wv2RLfWXfMvZYGpAAvfYWwzbyQ2i1q+tKE/thgKNscoSRellDD+uJcYn1H4hnaudVyYJH9miVhOKhKlExMzw8an6U=";
String strExponent = "AQAB";
byte[] modulusBytes = Base64.decode(strModulus, Base64.DEFAULT);
byte[] exponentBytes = Base64.decode(strExponent, Base64.DEFAULT);
BigInteger modulus = new BigInteger(1, modulusBytes );
BigInteger exponent = new BigInteger(1, exponentBytes);
RSAPublicKeySpec rsaPubKey = new RSAPublicKeySpec(modulus, exponent);
KeyFactory fact = KeyFactory.getInstance("RSA/ECB/PKCS1Padding");
PublicKey pubKey = fact.generatePublic(rsaPubKey);
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
byte[] plainBytes = new String("Manchester United").getBytes("UTF-8");
byte[] cipherData = cipher.doFinal(plainBytes);
encryptedString = Base64.encodeToString(cipherData, Base64.DEFAULT);
}
catch(Exception e){
Log.e("Error", e.toString());
}
return encryptedString;
The same code in Java:
try{
String strModulus = "tr82UfeGetV7yBKcOPjFTWs7pHqqr/5YKKWMUZHG4HnCmWrZsOhuR1FBnMZ/g2YiosoSlu0zd7Ukz9lX7wv2RLfWXfMvZYGpAAvfYWwzbyQ2i1q+tKE/thgKNscoSRellDD+uJcYn1H4hnaudVyYJH9miVhOKhKlExMzw8an6U=";
String strExponent = "AQAB";
byte[] modulusBytes = DatatypeConverter.parseBase64Binary("tr82UfeGetV7yBKcOPjFTWs7pHqqr/5YKKWMUZ/HG4HnCmWrZsOhuR1FBnMZ/g2YiosoSlu0zd7Ukz9lX7wv2RLfWXfMvZYGpAAvfYWwzbyQ2i1q+tKE/thgKNscoSRellDD+uJcYn1H4hnaudVyYJH9miVhOKhKlExMzw8an6U=");
byte[] exponentBytes = DatatypeConverter.parseBase64Binary("AQAB");
BigInteger modulus = new BigInteger(1, modulusBytes );
BigInteger exponent = new BigInteger(1, exponentBytes);
RSAPublicKeySpec rsaPubKey = new RSAPublicKeySpec(modulus, exponent);
KeyFactory fact = KeyFactory.getInstance("RSA");
PublicKey pubKey = fact.generatePublic(rsaPubKey);
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
byte[] plainBytes = new String("Manchester United").getBytes("UTF-8");
byte[] cipherData = cipher.doFinal(plainBytes);
//String encryptedString = Base64.encodeToString(cipherData, Base64.NO_PADDING);
String encryptedString = DatatypeConverter.printBase64Binary(cipherData);
String encryptedData = encryptedString;
}
catch(Exception e){
}
}
WCF Service:
public string Decrypt()
{
const int PROVIDER_RSA_FULL = 1;
const string CONTAINER_NAME = "Tracker";
CspParameters cspParams;
cspParams = new CspParameters(PROVIDER_RSA_FULL);
cspParams.KeyContainerName = CONTAINER_NAME;
RSACryptoServiceProvider rsa1 = new RSACryptoServiceProvider(cspParams);
rsa1.FromXmlString("<RSAKeyValue><Modulus>tr82UfeGetV7yBKcOPjFTWs7pHqqr/5YKKWMUZ/HG4HnCmWrZsOhuR1FBnMZ/g2YiosoSlu0zd7Ukz9lX7wv2RLfWXfMvZYGpAAvfYWwzbyQ2i1q+tKE/thgKNscoSRellDD+uJcYn1H4hnaudVyYJH9miVhOKhKlExMzw8an6U=</Modulus><Exponent>AQAB</Exponent><P>6e0nv7EBFBugtpoB+ozpg1J4js8E+DVyWCuBsERBPzqu4H7Z/oeLIRSC8Gi5GZgrCpBf3EvyIluM7rzaIfNThQ==</P><Q>x/29X9ns1WcXC42IJjLDjscz5ygdVh79dm8B2tQVbqwyhDsQ6OIOQdu5+eHf4hUMoTrM9KkS2F6FGlLXuaOFoQ==</Q><DP>kTS2LMaJ/dpce5zDx6w6s1q5HSSiWBSNIu/2s9zah448yXvUg6vNkD40PVk0NRAA/7C44H2AExWzOOqfmN17JQ==</DP><DQ>xtAx9drQPWnpl/uQUOEAVa0kpPTVDStrr9Q1FNTnpYkcAyYw7kLkB4anAIoSpk9kqdeprsNxz5VPXtbiTFMKYQ==</DQ><InverseQ>O0594NMjnjSp+/NAa1kQxoQNzn1qqq+p1Zb+kT3/jRc/0d7ZnqSSpxFMXfxx3yZkNAOPDOdbckPQbRZ13RKBHg==</InverseQ><D>bjVEagwvkrZaTt9CTW1hd3362weLFlX6DpE/3R3RcrpVfkSwKGpEhqGrNeeGPlsuqiaf5rAFir4eTqrF1QVliKsU4XE0RyzP5lHGc7dlX4DOHMjs2R9nNWv8QOTPoaRuLrLGorqBXlw/jQPxFI6gQzkIIjzuf//lDVnFam3dw4E=</D></RSAKeyValue>");
string data2Decrypt = "LyVNDhkdJ5jNgwZDiVZ1R0lmd10AQgqNDFHh2vJB1676eg8wj0MOdTyChAGrvEjha0uXg+f/aNBAc4+/LFbCgsA1e+O3wnXr27sXznGJ9G15avZzQHG4JWUS42MXBahAkcJ80pcihTbL9edfQCkEuj9RzQ/zFJyDEMssfd/EPDM=";
byte[] encyrptedBytes = Convert.FromBase64String(data2Decrypt);
byte[] plain = rsa1.Decrypt(encyrptedBytes, false);
string decryptedString = System.Text.Encoding.UTF8.GetString(plain);
}
Original Data : 'Manchester United'
The strange thing is that if I encrypt a string with the Java code it can be decrypted at the WCF service end, however, if it is encrypted using the above Android code, the decryption provides the error: "The data to be decrypted exceeds the maximum for this modulus of 128 bytes".
On debugging, I realized that the byte[] cipherData is not the same for Android and Java. All the previous values happen to be in sync. This generates different Encrypted Strings in Java and Android.
My question is why does this happen? Is there a silly mistake? Is there a way to work around it? Or something else that can be done in Android to get the 'Cipher Data' right?
Any help will be appreciated.
You are using a different padding on Android. Use the exact same padding on Android as well:
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
Here is the situation:
The encrypted text is done in JAVA (which we have no JAVA background at all)
The method is 3DES
The padded is PKCS#5
Base 64
The decryption will be in C#, and here is the code:
public static string DecryptString(string Message, string Passphrase)
{
byte[] Results;
UTF8Encoding UTF8 = new UTF8Encoding();
MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(Passphrase));
TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider();
TDESAlgorithm.Key = TDESKey;
TDESAlgorithm.Mode = CipherMode.ECB;
TDESAlgorithm.Padding = PaddingMode.PKCS7;
byte[] DataToDecrypt = Convert.FromBase64String(Message);
try
{
ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length);
}
finally
{
TDESAlgorithm.Clear();
HashProvider.Clear();
}
return UTF8.GetString(Results);
}
However, when tried to decrypt, got the error message: BAD DATA
Where am I missing here?
Thanks in advance.
Added, and here's how the encryption works:
<cffunction name="getToken" returntype="String" output="false">
<cfscript>
plainText = getPlainText();
rawSecretKey = CreateObject("java","sun.misc.BASE64Decoder").decodeBuffer(variables.encryptionKey);
secretKeySpec = CreateObject("java","javax.crypto.spec.SecretKeySpec").init(rawSecretKey,"DESEDE");
cipher = CreateObject("java","javax.crypto.Cipher").getInstance("DESEDE");
cipher.init(Cipher.ENCRYPT_MODE, secretkeySpec);
encrypted = cipher.doFinal(plainText.getBytes()); // a byte array (a binary in CF)
return URLEncodedFormat(ToString(ToBase64(encrypted)));
</cfscript>
</cffunction>
Update:
This issue has been resolved. The problem was that the key needed to be converted from Base64.
The answer:
Instead of:
byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(Passphrase));
Do this:
byte[] TDESKey = Convert.FromBase64String(Passphrase);
That solves this issue.