openssl_encrypt 256 CBC raw_data in java - java

I try to do a PHP openssl_encrypt aes-256-cbc with OPENSSL_RAW_DATA in java 6 without success. I found some topic about this, but I'ved successful only to do it in aes-128-cbc without raw_data. The best topic I founded about this it's : AES-256 CBC encrypt in php and decrypt in Java or vice-versa
But the raw_data doesn't work and the 256 bits key is randomly generated.
In fact the Php version is :
<?php>
openssl(
"hello",
"aes-256-cbc",
"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
OPENSSL_RAW_DATA,
"aaaaaaaaaaaaaaaa"
)
?>
And I actually have this :
public static void main(String[] args) {
try {
// 128 bits key
openssl_encrypt("hello", "bbbbbbbbbbbbbbbb", "aaaaaaaaaaaaaaaa");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private static String openssl_encrypt(String data, String strKey, String strIv) throws Exception {
Base64 base64 = new Base64();
Cipher ciper = Cipher.getInstance("AES/CBC/PKCS5Padding");
SecretKeySpec key = new SecretKeySpec(strKey.getBytes("UTF-8"), "AES");
IvParameterSpec iv = new IvParameterSpec(strIv.getBytes("UTF-8"), 0, ciper.getBlockSize());
// Encrypt
ciper.init(Cipher.ENCRYPT_MODE, key, iv);
byte[] encryptedCiperBytes = base64.encode((ciper.doFinal(data.getBytes())));
String s = new String(encryptedCiperBytes);
System.out.println("Ciper : " + s);
return s;
}

After few modification and some testing I found it :
private static String openssl_encrypt(String data, String strKey, String strIv) throws Exception {
Base64 base64 = new Base64();
Cipher ciper = Cipher.getInstance("AES/CBC/PKCS5Padding");
SecretKeySpec key = new SecretKeySpec(strKey.getBytes(), "AES");
IvParameterSpec iv = new IvParameterSpec(strIv.getBytes(), 0, ciper.getBlockSize());
// Encrypt
ciper.init(Cipher.ENCRYPT_MODE, key, iv);
byte[] encryptedCiperBytes = ciper.doFinal(data.getBytes());
String s = new String(encryptedCiperBytes);
System.out.println("Ciper : " + s);
return s;
}
openssl_encrypt in PHP don't convert his result in base64, and I also use getBytes() without param cause, for some keys, I had an error about the key's lentgh.
So this method do the same thing than :
<?php>
openssl_encrypt(data, "aes-256-cbc", key, OPENSSL_RAW_DATA, iv);
?>

Related

Decryption not returning correct plaintext [closed]

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I am trying to create a simple AES encryption/decryption module for use in a larger project, but I'm having trouble getting the AES methods to work. I've done a good amount of research, but I can't figure out what is going wrong within my code (I'm suspecting something simple that I'm missing).
Main:
public static byte[] genKey() {
// Create key generator
KeyGenerator keyGen;
try {
keyGen = KeyGenerator.getInstance("AES");
}
catch(GeneralSecurityException e) {
e.printStackTrace();
return null;
}
// Create random byte generator
SecureRandom r = new SecureRandom();
// Initialize key generator
keyGen.init(256, r);
SecretKey key = keyGen.generateKey();
return key.getEncoded();
}
public static void main(String[] args) throws GeneralSecurityException {
// write your code here
// Create AES handler
AES aes = new AES();
// Generate key
byte[] key = genKey();
// Set key for AES
aes.setKey(key);
Scanner in = new Scanner(System.in);
System.out.print("Please enter a phrase to encrypt: ");
String input = in.nextLine();
// Encrypt phrase
byte[][] encrypted = aes.encrypt(input);
// Decrypt phrase
String plaintext = aes.decrypt(encrypted[0], encrypted[1]);
// Print results
System.out.println("Ciphertext: " + encrypted[1]);
System.out.println("Plaintext: " + plaintext);
}
AES:
private Cipher cipher;
private SecretKey key;
public AES() {
// Create Cipher
try {
cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
} catch (GeneralSecurityException e) {
e.printStackTrace();
}
}
public void setKey(byte[] key) {
this.key = new SecretKeySpec(key, "AES");
}
public byte[][] encrypt(String plaintext) throws GeneralSecurityException {
System.out.println("Using key : " + key.getEncoded() + " to encrypt");
byte[][] values = new byte[2][];
// Decode plaintext into bytes
byte[] decodedPlaintext = new byte[0];
try {
decodedPlaintext = plaintext.getBytes("UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
// Generate an IV and set up the Cipher to encrypt
byte[] ivBytes = new byte[16];
SecureRandom rand = new SecureRandom();
rand.nextBytes(ivBytes);
IvParameterSpec iv = new IvParameterSpec(ivBytes);
cipher.init(Cipher.ENCRYPT_MODE, key, iv);
// Encrypt decoded plaintext
byte[] ciphertext = cipher.doFinal(decodedPlaintext);
values[0] = ivBytes;
values[1] = ciphertext;
return values;
}
public String decrypt(byte[] ivBytes, byte[] ciphertext) throws GeneralSecurityException {
System.out.println("Using key " + key.getEncoded() + " to decrypt");
// Set up cipher to decrypt
IvParameterSpec iv = new IvParameterSpec(ivBytes);
cipher.init(Cipher.DECRYPT_MODE, key, iv);
byte[] decodedPlaintext = cipher.doFinal(ciphertext);
// Encode plaintext
String plaintext = Base64.getEncoder().encodeToString(decodedPlaintext);
return plaintext;
}
Results:
Please enter a phrase to encrypt: test
Using key : [B#442d9b6e to encrypt
Using key [B#3d012ddd to decrypt
Ciphertext: [B#515f550a
Plaintext: dGVzdA==
I don't understand why my encryption/decryption seem to be using different keys when I only set the key once in the beginning. Am I creating a key wrong?
I've also tried:
byte[] key = new byte[32];
SecureRandom r = new SecureRandom();
r.nextBytes(key);
// Set key for AES
aes.setKey(key);
And run into the same issue.
If you trace this.key in AES class all the way through encode and decode using Arrays.toString(this.key.getEncoded()) it does look like it's using a persistent key.
this.key.getEncoded().toString()) returns a different representation each time but it seems like the actual byte array is the same.
I replaced
String plaintext = Base64.getEncoder().encodeToString(decodedPlaintext);
with
String plaintext = new String(decodedPlaintext, StandardCharsets.UTF_8);
and it seemed to work.

Java equivalent of openssl_encrypt and openssl_decrypt using AES 256 CBC encryption with provided secret key and IV

I am using third party application which is in PHP and mine is in java, for which I need to send a few data in an encrypted format. They have shared the secret key and IV. But I am not able to get the same output as they are getting while encryption. Although whatever I am encrypting in java, I am able to get the same while decrypting in java. Please help me out with this.
public static String secret_key = "abc";
public static String secret_iv = "abc#243";
public static String strKeyString = toHexString(getSHA(secret_key));
public static String ivString = toHexString(getSHA(secret_iv));
public static String strKey= strKeyString.substring(0, 16);
public static String strIv = ivString.substring(0, 16);
public static byte[] getSHA(String input)
{
// Static getInstance method is called with hashing SHA
MessageDigest md;
try {
md = MessageDigest.getInstance("SHA-256");
// digest() method called
// to calculate message digest of an input
// and return array of byte
return md.digest(input.getBytes(StandardCharsets.UTF_8));
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
public static String toHexString(byte[] hash)
{
// Convert byte array into signum representation
BigInteger number = new BigInteger(1, hash);
// Convert message digest into hex value
StringBuilder hexString = new StringBuilder(number.toString(16));
// Pad with leading zeros
while (hexString.length() < 32)
{
hexString.insert(0, '0');
}
return hexString.toString();
}
public static String openssl_encrypt(String data) throws Exception {
Cipher ciper = Cipher.getInstance("AES/CBC/PKCS5Padding");
SecretKeySpec key = new SecretKeySpec(strKey.getBytes(), "AES");
IvParameterSpec iv = new IvParameterSpec(strIv.getBytes(), 0, ciper.getBlockSize());
// Encrypt
ciper.init(Cipher.ENCRYPT_MODE, key, iv);
byte[] encryptedCiperBytes = ciper.doFinal(data.getBytes());
System.out.println("Ciper encrypted : " + Base64.encodeBase64String(encryptedCiperBytes));
//Decrypt
ciper.init(Cipher.DECRYPT_MODE, key, iv);
byte[] output = ciper.doFinal(Base64.decodeBase64(Base64.encodeBase64String(encryptedCiperBytes)));
System.out.println("Ciper decrypted : " +new String(output).trim());
return Base64.encodeBase64String(encryptedCiperBytes);
}

javax.crypto.BadPaddingException: pad block corrupted sometimes

I have the following code for encrypt
public static String encrypt(String value, char[] secret) {
try {
final byte[] bytes = value != null ? value.getBytes(StandardCharsets.UTF_8) : new byte[0];
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(secret));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
pbeCipher.init(Cipher.ENCRYPT_MODE, key, new PBEParameterSpec(IsoGame.$().crossPlatformManager.getCrossPlatformUtilsInstance().getDeviceUniqueIdentifier().getBytes(StandardCharsets.UTF_8), 20));
return new String(Base64.encodeBase64(pbeCipher.doFinal(bytes)), StandardCharsets.UTF_8);
} catch (Exception e) {
e.printStackTrace();
}
return value;
}
and the following code for decrypt.
public static String decrypt(String value, char[] secret) {
try {
final byte[] bytes = value != null ? Base64.decodeBase64(value.getBytes(StandardCharsets.UTF_8)) : new byte[0];
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(secret));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
pbeCipher.init(Cipher.DECRYPT_MODE, key, new PBEParameterSpec(IsoGame.$().crossPlatformManager.getCrossPlatformUtilsInstance().getDeviceUniqueIdentifier().getBytes(StandardCharsets.UTF_8), 20));
return new String(pbeCipher.doFinal(bytes), StandardCharsets.UTF_8);
} catch (Exception e) {
e.printStackTrace();
}
return value;
}
However, sometimes the exception is being thrown at
pbeCipher.doFinal(bytes)
in decrypt method.
The exception is javax.crypto.BadPaddingException: pad block corrupted
It's strange, as I'm getting this exception sometimes with the same values .
Any ideas?
Thanks.
The most likely reason would simply be the wrong password to be supplied. If the wrong password is supplied then the wrong key is derived. Then the ciphertext will be decrypted to garbage plaintext. This will only be noticed if the padding exception gets thrown: unpadding random bytes is likely to fail.
You could e.g. first validate that the derived key is correct by performing a HMAC over known data using the derived key. In addition, it would be a good idea to use some kind of authenticated encryption, so that if the key or data is wrong or corrupted that decryption does indeed fail. If you're unlucky then - at this time - the data will decrypt, unpadding will succeed and you end up with garbage plaintext.
Of course, you'd better upgrade to PBKDF2 for key derivation, and upgrade AES to e.g. AES-GCM instead of DES. Currently your encryption is entirely insecure, even if you use a strong password.
Your problem is
IsoGame.$().crossPlatformManager.getCrossPlatformUtilsInstance().getDeviceUniqueIdentifier().getBytes(StandardCharsets.UTF_8)
I have ran the following code multiple times and no exception occurred and the decrypted data was equal to "Hello there!":
public static void main(String[] args)
{
new CryptographyError();
}
private CryptographyError()
{
char[] secret = "MySecret".toCharArray();
String mesasge = "Hello there!";
EncryptedData encryptedData = encrypt(mesasge, secret);
System.out.println("ENCRYPTED " + encryptedData.encryptedString);
String decrypted = decrypt(encryptedData, secret);
System.out.println("DECRYPTED " + decrypted);
}
private static final SecureRandom RANDOM = new SecureRandom();
public static EncryptedData encrypt(String value, char[] secret) {
try {
final byte[] bytes = value != null ? value.getBytes(StandardCharsets.UTF_8) : new byte[0];
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(secret));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
byte[] salt = new byte[8];
RANDOM.nextBytes(salt);
pbeCipher.init(Cipher.ENCRYPT_MODE, key, new PBEParameterSpec(salt, 20));
return new EncryptedData(salt, new String(Base64.getEncoder().encode(pbeCipher.doFinal(bytes)), StandardCharsets.UTF_8));
} catch (Exception e) {
e.printStackTrace();
System.out.println(value);
}
return null;
}
public static String decrypt(EncryptedData encryptedData, char[] secret) {
try {
String value = encryptedData.encryptedString;
byte[] salt = encryptedData.salt;
final byte[] bytes = value != null ? Base64.getDecoder().decode(value.getBytes(StandardCharsets.UTF_8)) : new byte[0];
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = keyFactory.generateSecret(new PBEKeySpec(secret));
Cipher pbeCipher = Cipher.getInstance("PBEWithMD5AndDES");
pbeCipher.init(Cipher.DECRYPT_MODE, key, new PBEParameterSpec(salt, 20));
return new String(pbeCipher.doFinal(bytes), StandardCharsets.UTF_8);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static class EncryptedData
{
private final byte[] salt;
private final String encryptedString;
private EncryptedData(byte[] salt, String encryptedString)
{
this.salt = salt;
this.encryptedString = encryptedString;
}
}
The only main difference between my code and your code is
IsoGame.$().crossPlatformManager.getCrossPlatformUtilsInstance().getDeviceUniqueIdentifier().getBytes(StandardCharsets.UTF_8)
which means that must not return the same value on encryption and decryption.
Also if you want to test this you can just change the salt between them and notice the exception is thrown again.
Also Maarten Bodewes gave you some good notes about how to improve your code.

AES CBC 128 bit encryption using Java and PHP

I have recently used the AES CBC 128 algorithm in Java in order to cipher data. Now I need to rebuild that algorithm in PHP, but I have no idea how, because PHP algorithms on the internet return different results. Maybe you can help me.
This is the Java-code to encrypt:
private SecretKeySpec secretKey;
private IvParameterSpec ivSpec;
public void setKey(String myKey) {
MessageDigest sha = null;
try {
byte[] key = myKey.getBytes("UTF-8");
sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16);
secretKey = new SecretKeySpec(key, "AES");
byte[] iv = new String("1010101010101010").getBytes("UTF-8");
ivSpec = new IvParameterSpec(iv);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
public String encrypt(String strToEncrypt) {
try {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivSpec);
return Base64.encode(cipher.doFinal(strToEncrypt.getBytes("UTF-8")));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public String decrypt(String strToDecrypt) {
try {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secretKey, ivSpec);
return new String(cipher.doFinal(Base64.decode(strToDecrypt)));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static void main(String[] args) {
AESText aes = new AESText();
final String secretKey = "com.secure.test.projectjasdS/FjkGkGhkGjhG786Vjfg=tjGFGH";
aes.setKey(secretKey);
String originalString = "test set se ts et set s et se";
String encryptedString = aes.encrypt(originalString);
String decryptedString = aes.decrypt(encryptedString);
System.out.println("origin: " + originalString);
System.out.println("encrypted: " + encryptedString);
System.out.println("decrypted: " + decryptedString);
}
This is my php code:
protected $key;
protected $method = 'AES-128-CBC';
protected $iv = '1010101010101010';
protected $option = OPENSSL_CIPHER_AES_128_CBC;
function __construct($key)
{
$this->key = $key;
}
public function encrypt($data) {
if (is_null($data)) {
return "Error " . INVALID_PARAMS_ENCRYPTIONS . ": Data is null ";
}
$enc = openssl_encrypt($data, $this->method, $this->key, $this->option, $this->iv);
return base64_encode($enc);
}
public function decrypt($data) {
if (is_null($data)) {
return "Error " . INVALID_PARAMS_ENCRYPTIONS . ": Data is null ";
}
$data = base64_decode($data);
$dec = openssl_decrypt($data, $this->method, $this->key, $this->option, $this->iv);
return $dec;
}
When I encrypted data from java encryption, This result cannot decrypt on Php decryption.
Can you guys possibly help me with building a PHP script, that returns the same results with java encryption?
At first glance I see three issues here:
First: you are not using the same mode: in java you have AES/ECB/PKCS5Padding whereas your php uses AES-128-CBC.
Second: you probably aren't using the same IV's in the Java and PHP code (IV's are irrelevant for ECB, but once you switch your java to CBC you will need it):
You have $iv = '1010101010101010' (which is then passed to openssl) in your php but nothing like that in your java.
At the very least, you will probably need something like that in your Java part as well:
cipher.init(Cipher.DECRYPT_MODE/ENCRYPT_MODE, secretKey, new IvParameterSpec(iv))
with iv being a byte[] containing your IV bytes.
Third: once the problems above are addressed, padding may be the next breaking thing: your java cipher specification mentions PKCS5Padding. You need to make sure that both of your counterparts use the same.
edit: Fourth: One more issue is the way you derive the key bits to be used. In java you take the first 16 bytes of a sha1-hash, and in php you just pass $key to openssl. openssl might be deriving the encryption key in a different way.
When building cryptography-related tools using block ciphers, it's always nice to revisit classics like Block cipher mode of operation and Padding on Wikipedia, to get a sense of what is going on under the hood.

how to convert a string in to a byte array

I've wrote a method to encrypt/decrypt a string. Encryption is happening successfully but I cannot manage to make the decryption work... This is the code I have written:
public String encrypt(String a, int x) {
String ret = "";
String text = a;
String key = "Bar12345Bar12345"; // 128 bit key
try {
// Create key and cipher
Key aesKey = new SecretKeySpec(key.getBytes(), "AES");
Cipher cipher = Cipher.getInstance("AES");
if(x == 0) { //x==0 means I want to encrypt
// encrypt the text
cipher.init(Cipher.ENCRYPT_MODE, aesKey);
byte[] encrypted = cipher.doFinal(text.getBytes());
ret =new String(encrypted);
}
else { //if not 0 I want to decrypt
// decrypt the text
byte[] encrypted = text.getBytes(Charset.forName("UTF-8"));
cipher.init(Cipher.DECRYPT_MODE, aesKey);
String decrypted = new String(cipher.doFinal(encrypted));
ret=decrypted;
}
} catch(Exception e) {
e.printStackTrace();
}
return ret;
}
I think the problem arise when I'm trying to convert the string into byte array. The error I get is:
javax.crypto.BadPaddingException: Given final block not properly padded
So what is the problem ? If I am not converting the string into byte array in right way, how should I do it ?

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