I have been trying to send data effectively between two applications. One is implemented in C# (Sender) the other in Java (Receiver). The sender has to encrypt data using the transformation "AES/GCM/NOPadding" with a 32-byte key while the receiver has to decrypt using the same parameters. Here is the sender encryption function in C# (using bouncy castle)
public static string Encrypt(string plainText, string msgId)
{
const byte GcmTagSize = 16;
byte[] hashKey;
byte[] secretKey = Encoding.UTF8.GetBytes(msgId);
Console.WriteLine(secretKey.Length);
using (var hasher = SHA512.Create())
{
byte[] digestSeed = hasher.ComputeHash(secretKey);
hashKey = new byte[16];
Array.Copy(digestSeed, hashKey, hashKey.Length);
}
var keyParameter = new KeyParameter(hashKey);
var keyParameters = new AeadParameters(keyParameter, GcmTagSize * 8, secretKey);
var cipher = CipherUtilities.GetCipher("AES/GCM/NoPadding");
cipher.Init(true, keyParameters);
var plainTextData = Encoding.ASCII.GetBytes(plainText);
var cipherText = cipher.DoFinal(plainTextData); //bouncy castle
return Convert.ToBase64String(cipherText);
}
Here is the receiver decryption function in java
private static byte[] decrypt(byte[] message, SecretKey key) throws NoSuchPaddingException, NoSuchAlgorithmException,
IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException, InvalidKeyException {
Cipher cipher = Cipher.getInstance("AES/GCM/NOPadding"); //NoPadding
byte[] nonce = Arrays.copyOfRange(message, message.length - cipher.getBlockSize(), message.length);
byte[] encryptedKycData = Arrays.copyOf(message, message.length - cipher.getBlockSize());
System.out.println(doEncode(nonce));
System.out.println(doEncode(nonce));
GCMParameterSpec gcmParameterSpec = new GCMParameterSpec(128, nonce);
cipher.init(Cipher.DECRYPT_MODE, key, gcmParameterSpec);
byte[] decryptedValue=cipher.doFinal(encryptedKycData);
return decryptedValue;
}
When I try to decrypt with the java decryption function I get the error
javax.crypto.AEADBadTagException: Tag mismatch
Struggling with this issue and any help would be appreciated.
I am using one encryption/decryption method used in java and applying it in php . I have almost reached to the end but there is one mistake which I found that my decrypted string is not what i was expecting ,
This is my java code
private static final String ALGORITHM = "AES/CBC/PKCS5Padding";
public static String encrypt(String message, String key) throws GeneralSecurityException, UnsupportedEncodingException {
if (message == null || key == null) {
throw new IllegalArgumentException("text to be encrypted and key should not be null");
}
Cipher cipher = Cipher.getInstance(ALGORITHM);
byte[] messageArr = message.getBytes();
byte[] keyparam = key.getBytes();
SecretKeySpec keySpec = new SecretKeySpec(keyparam, "AES");
byte[] ivParams = new byte[16];
byte[] encoded = new byte[messageArr.length + 16];
System.arraycopy(ivParams, 0, encoded, 0, 16);
System.arraycopy(messageArr, 0, encoded, 16, messageArr.length);
cipher.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(ivParams));
byte[] encryptedBytes = cipher.doFinal(encoded);
encryptedBytes = Base64.getEncoder().encode(encryptedBytes);
return new String(encryptedBytes);
}
public static String decrypt(String encryptedStr, String key) throws GeneralSecurityException, UnsupportedEncodingException {
if (encryptedStr == null || key == null) {
throw new IllegalArgumentException("text to be decrypted and key should not be null");
}
Cipher cipher = Cipher.getInstance(ALGORITHM);
byte[] keyparam = key.getBytes();
SecretKeySpec keySpec = new SecretKeySpec(keyparam, "AES");
byte[] encoded = encryptedStr.getBytes();
encoded = Base64.getDecoder().decode(encoded);
byte[] decodedEncrypted = new byte[encoded.length - 16];
System.arraycopy(encoded, 16, decodedEncrypted, 0, encoded.length - 16);
byte[] ivParams = new byte[16];
System.arraycopy(encoded, 0, ivParams, 0, ivParams.length);
cipher.init(Cipher.DECRYPT_MODE, keySpec, new IvParameterSpec(ivParams));
byte[] decryptedBytes = cipher.doFinal(decodedEncrypted);
return new String(decryptedBytes);
}
now i have done this in php like this
$encKey = 'encryptionKey';
$cipher = "aes-256-cbc";
$data = 'some data';
$encryption_key = openssl_random_pseudo_bytes(32);
$iv_size = openssl_cipher_iv_length($cipher);
$iv = openssl_random_pseudo_bytes($iv_size);
$ciphertext_raw = openssl_encrypt(json_encode($data), 'aes-256-cbc', $encKey, $options = OPENSSL_RAW_DATA, $iv);
//$ciphertext_raw = openssl_encrypt(json_encode($data), $cipher, $encKey, $options=OPENSSL_RAW_DATA, $iv);
$encrypted_data = base64_encode($iv . $ciphertext_raw);
print_r($encrypted_data);
now the problem is when i encrypt one string in php and decrypt it in java code it add some escape sequence but when i encrypt that same string in java and decrypt it in java it is proper and accurate and i am not sure why this is happening ... may be i am doing some thing wrong
as I have to do this encryption in php using java code i am not sure that is this process going in right way or there is some error .
this is the string which i am encrypting
String str = "vendor_id=INT_GTW&format=json&msg_code=KBEX99&data={\"header\":{\"msg_code\":\"KBEX99\",\"source\":\"INSTANTPAY\",\"channel\":\"CONBNK\",\"txn_ref_number\":\"INSTANTPAY_CONBNK_00001\",\"txn_datetime\":\"1498118309808\",\"ip\":\"1\",\"device_id\":\"XYWZPQR123\",\"api_version\":\"1.0.0\"},\"detail\":{\"entity\":\"INSTANTPAY\",\"intent\":\"REG\",\"user_identifier\":\"INSTANTPAY28423928\",\"crn\":\"105683710\",\"p1\":\"105683710\",\"p2\":\"\",\"p3\":\"INSTANTPAY\",\"p4\":\"\",\"p5\":\"\",\"p6\":\"\",\"p7\":\"\",\"p8\":\"\",\"p9\":\"\",\"p10\":\"\",\"p11\":\"\",\"p12\":\"\",\"p13\":\"\",\"p14\":\"\",\"p15\":\"\",\"p16\":\"\",\"p17\":\"\",\"p18\":\"\",\"p19\":\"\",\"p20\":\"\"}}";
and this is decrypted string
vendor_id=INT_GTW&format=json&msg_code=KBEX99&data={"header":{"msg_code":"KBEX99","source":"INSTANTPAY","channel":"CONBNK","txn_ref_number":"INSTANTPAY_CONBNK_00001","txn_datetime":"1498118309808","ip":"1","device_id":"XYWZPQR123","api_version":"1.0.0"},"detail":{"entity":"INSTANTPAY","intent":"REG","user_identifier":"INSTANTPAY28423928","crn":"105683710","p1":"105683710","p2":"","p3":"INSTANTPAY","p4":"","p5":"","p6":"","p7":"","p8":"","p9":"","p10":"","p11":"","p12":"","p13":"","p14":"","p15":"","p16":"","p17":"","p18":"","p19":"","p20":""}}
but when i am doing it in php and decrypting
"vendor_id=INT_GTW&format=json&msg_code=KBEX99&data={\"header\":{\"msg_code\":\"KBEX99\",\"source\":\"INSTANTPAY\",\"channel\":\"CONBNK\",\"txn_ref_number\":\"INSTANTPAY_CONBNK_00001\",\"txn_datetime\":\"1498118309808\",\"ip\":\"1\",\"device_id\":\"XYWZPQR123\",\"api_version\":\"1.0.0\"},\"detail\":{\"entity\":\"INSTANTPAY\",\"intent\":\"REG\",\"user_identifier\":\"INSTANTPAY28423928\",\"crn\":\"105683710\",\"p1\":\"105683710\",\"p2\":\"\",\"p3\":\"INSTANTPAY\",\"p4\":\"\",\"p5\":\"\",\"p6\":\"\",\"p7\":\"\",\"p8\":\"\",\"p9\":\"\",\"p10\":\"\",\"p11\":\"\",\"p12\":\"\",\"p13\":\"\",\"p14\":\"\",\"p15\":\"\",\"p16\":\"\",\"p17\":\"\",\"p18\":\"\",\"p19\":\"\",\"p20\":\"\"}}"
i am getting this
So any encryption decryption expert please help me in this ...
Thank you !!
I'm trying to encrypt and decrypt some texts using Cipher with the "AES/CBC/PKCS5Padding" algorithm but if I restart the application the text that was encrypt can't be decrypted.
I'm encrypting the text, transforming the encrypted bytes in base64 text, storing it and retrieving it when necessary, so transforming the base64 text in bytes and trying to decrypt to take the original text.
The code I'm using is:
private static SecretKey getKeyFromPassword(String password, String salt)
throws NoSuchAlgorithmException, InvalidKeySpecException {
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
KeySpec spec = new PBEKeySpec(password.toCharArray(), salt.getBytes(UTF_8),
65536, 256);
SecretKey secret = new SecretKeySpec(factory.generateSecret(spec)
.getEncoded(), "AES");
return secret;
}
private static IvParameterSpec generateIv() {
byte[] iv = new byte[16];
new SecureRandom().nextBytes(iv);
return new IvParameterSpec(iv);
}
public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeySpecException, InvalidAlgorithmParameterException, InvalidKeyException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException {
// string for test
String teste = "teste teste teste teste";
//getting start with Cipher
SecretKey secretKey = getKeyFromPassword("pass", "salt");
IvParameterSpec ivParameterSpec = generateIv();
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
//encrypting
cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivParameterSpec);
byte[] cipherText = new byte[0];
cipherText = cipher.doFinal(teste.getBytes(UTF_8));
// encrypt to base64 text
String criptado = Base64.getEncoder().encodeToString(cipherText);
//decripting
byte[] plainText = new byte[0];
byte[] rawText = Base64.getDecoder().decode(criptado);
cipher.init(Cipher.DECRYPT_MODE, secretKey, ivParameterSpec);
plainText = cipher.doFinal(rawText);
String decriptado = new String(plainText);
The problem is something with the size of the bit key? Like in this topic: java AES/CBC/PKCS5PADDING in php (AES-256-CBC) resulting different result
I took this guide to the code: baeldung.com/java-aes-encryption-decryption
I want to use JAVA encryption and decryption logic in qt creator code i tried and search lot of stuff but success for "DES/CBC" Encryption and Decryption Logic but not useful for me Because JAVA code is in "DESede/CBC/PKCS5Padding" Triple DES logic.
JAVA CODE is as follows:
public static String initializationVector = "abhijeet";
public static String key="XB13347FE570DC4FFB13647F";
public String encryptText(String plainText) throws Exception {
// ---- Use specified 3DES key and IV from other source --------------
byte[] plaintext = plainText.getBytes();
byte[] tdesKeyData = Config.key.getBytes();
// byte[] myIV = initializationVector.getBytes();
Cipher c3des = Cipher.getInstance("DESede/CBC/PKCS5Padding");
SecretKeySpec myKey = new SecretKeySpec(tdesKeyData, "DESede");
IvParameterSpec ivspec = new IvParameterSpec(Config.initializationVector.getBytes());
c3des.init(Cipher.ENCRYPT_MODE, myKey, ivspec);
byte[] cipherText = c3des.doFinal(plaintext);
return new BASE64Encoder().encode(cipherText);
}
public static String decryptText(String cipherText) throws Exception {
byte[] encData = new BASE64Decoder().decodeBuffer(cipherText);
Cipher decipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
byte[] tdesKeyData = Config.key.getBytes();
SecretKeySpec myKey = new SecretKeySpec(tdesKeyData, "DESede");
IvParameterSpec ivspec = new IvParameterSpec(Config.initializationVector.getBytes());
decipher.init(Cipher.DECRYPT_MODE, myKey, ivspec);
byte[] plainText = decipher.doFinal(encData);
return new String(plainText);
}
Example :
Input string - "Hello"
After Encryption Output string - "c13FZpr4odg="
Please Help for the same as i stuck here
I am using AESCrypt (gradle :compile 'com.scottyab:aescrypt:0.0.1')
to encrypt and decrypt the data.
TextView tv=(TextView)findViewById(R.id.demotext);
String encrypted="",decrypted="";
try {
encrypted = AESCrypt.encrypt("password","This is the best thing to go by");
decrypted = AESCrypt.decrypt("password",encrypted);
} catch (GeneralSecurityException e) {
e.printStackTrace();
}
System.out.println("EncryptedData:"+encrypted);
System.out.println("DecryptedData:"+decrypted);
tv.setText("Encrypted:"+encrypted +"\n"+"Decrypted:"+decrypted);
The code works perfectly fine in this case, I get the same input as decrypted text.
But, when I try to use already encrypted string using the same method (AES) from the site http://aesencryption.net/ as shown in the screenshot:
And copy paste that encrypted text like:
decrypted = AESCrypt.decrypt("password","sttA+FbNm3RkTovjHI8CcAdStXiMl45s29Jqle+y+pA=");
And then run the code then I get error saying :
javax.crypto.BadPaddingException: error:1e06b065:Cipher functions:EVP_DecryptFinal_ex:BAD_DECRYPT
But when I use the decrypted text into the same site it works fine as shown in the screenshot below.
private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] decrypted = cipher.doFinal(encrypted);
return decrypted;
}
Probably due to the algorithm to convert the passphrase 'password' to SecretKeySpec
This is the algorithm in AESCrypt
private static SecretKeySpec GenerateKey (final String password) throws NoSuchAlgorithmException, UnsupportedEncodingException {
final MessageDigest digest = MessageDigest.getInstance (HASH_ALGORITHM);
byte [] bytes = password.getBytes ("UTF-8");
digest.update (bytes, 0, bytes.length);
byte [] key = digest.digest ();
log ("SHA-256 key" key);
SecretKeySpec secretKeySpec = new SecretKeySpec (key, "AES");
secretKeySpec return;
}
And this is the (Java) example aesencryption.net
sha = MessageDigest.getInstance ("SHA-1");
key = sha.digest (key);
key = Arrays.copyOf (key, 16); // Use only first 128 bit
SecretKey = new SecretKeySpec (key, "AES");
The first one applies SHA256 hashing, and the second SHA-1 after completing up to 16 bytes, so the key is different.
I think you are encrypting and decrypting AES in the right way. You do not need to change anything.
But if you want to be compatible with aesencryption.net, you need to implement the same key generation algorithm. The code is not too good. I try to summarize
//Code from aesencryption.net
// Generate key
MessageDigest sha = null;
key = myKey.getBytes ("UTF-8");
sha = MessageDigest.getInstance ("SHA-1");
key = sha.digest (key);
key = Arrays.copyOf (key, 16); // Use only first 128 bit
SecretKey = new SecretKeySpec (key, "AES");
public static String encrypt (String strToEncrypt) {
Cipher cipher = Cipher.getInstance ("AES / ECB / PKCS5Padding");
cipher.init (Cipher.ENCRYPT_MODE, SecretKey);
Base64.encodeBase64String return (cipher.doFinal (strToEncrypt.getBytes ("UTF-8"))));
}
public static String decrypt (String strToDecrypt) {
Cipher cipher = Cipher.getInstance ("AES / ECB / PKCS5PADDING");
cipher.init (Cipher.DECRYPT_MODE, SecretKey);
return new String (cipher.doFinal (Base64.decodeBase64 (strToDecrypt))));
}
I can also provide my own code extracted from an Android app witch requires to store private user data. Data is ciphered with an AES key protected with an user passphrase
public static String SIMMETRICAL_ALGORITHM = "AES";
//Generate cipher key with user provided password
private static String getPassphraseSize16(String key) {
if (TextUtils.isEmpty(key)) {
return null;
}
char controlChar = '\u0014';
String key16 = key + controlChar;
if (key16.length() < 16) {
while (key16.length() < 16) {
key16 += key + controlChar;
}
}
if (key16.length() > 16) {
key16 = key16.substring(key16.length() - 16, key16.length());
}
return key16;
}
//AES cipher with passphrase
public static byte[] encrypt(byte[] message, String passphrase)
throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
String passphrase16 = getPassphraseSize16(passphrase);
SecretKeySpec secretKey = new SecretKeySpec(passphrase16.getBytes(), SIMMETRICAL_ALGORITHM);
Cipher cipher = Cipher.getInstance(SIMMETRICAL_ALGORITHM);
cipher.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] encoded = cipher.doFinal(message);
return encoded;
}
//AES decipher with passphrase
public static byte[] decrypt(byte[] encodedMessage, String key) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
String passphrase16 = getPassphraseSize16(key);
SecretKeySpec secretKey = new SecretKeySpec(passphrase16.getBytes(), SIMMETRICAL_ALGORITHM);
Cipher cipher = Cipher.getInstance(SIMMETRICAL_ALGORITHM);
cipher.init(Cipher.DECRYPT_MODE, secretKey);
byte decoded[] = cipher.doFinal(encodedMessage);
return decoded;
}