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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.

Able to decrypt an encrypted text in Java despite changing the encrypted text

I have the following code:
public static void main(final String[] args) throws Exception {
try {
String textToEncrypt = "{asdfsad asdf;ls kasdf asdlfjaslfjalksdfjlkadsjflkasfjl;kasj alkdfjaslkfj \r\n" +
"asdfjl;asdfjlasdjfdasfjfdosafjadsf \r\n" +
"as;ldfjal;ksfjlkdasfjadsf" +
"a;ldfjal;ksfjds" +
"}";
String secret = "SOME_SECRET";
String escapedTextToEncrypt = StringEscapeUtils.escapeJava(textToEncrypt);
System.out.println(escapedTextToEncrypt);
String encryptedText = SomeEncryption.encrypt(escapedTextToEncrypt, secret);
encryptedText = encryptedText.concat("3asdasfd"); // CHANGING THE ENCRYPTED TEXT!
System.out.println("Encrypted Text :" + encryptedText);
System.out.println("Decrypted Text :" + SomeEncryption.decrypt(encryptedText, secret)); // THIS WORKS!!
}catch(Throwable t){
t.printStackTrace();
}
}
I am using AES encryption algorithm and apache commons codec. Curiously, when I append a string to the encrypted text, it is still able to decrypt it with no problems. Am I missing something here?
More details:
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2withHmacSHA1");
SecretKeySpec secret = new SecretKeySpec(secretKey.getEncoded(), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
EDIT:
I am using StringEscapeUtils from apache commons lang library.

We found the answer to this question. If I add any string at the end of the encrypted string then it works. But if it is inserted in the middle then it fails.
encryptedText = new StringBuilder(encryptedText).insert(0, "xyz").toString();
The above fails.

openssl_encrypt 256 CBC raw_data in 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);
?>

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 ?

Encryption of strings using AES 128 in Java/grails

I would like to encrypt 3 strings using AES 128 in Java / Grails, and using the code below, but i get the error "An error occurred when encrypting", can someone tell me what is wrong with my code, how to fix it. thanks in advance and to Stackoverflow.
String url = "https://someurl.com"
String token = createToken(bookNumber, invNumber, cusNumber)
url += '?ref=' + token
class AesEncryptor {
static byte[] encrypt(String clearText) {
byte[] encrypted = null
try {
byte[] iv = new byte[16]
Arrays.fill(iv, (byte) 0)
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING")
encrypted = cipher.doFinal(clearText.getBytes("UTF-8"))
}
catch (Exception e) {
log.error "An error occurred when encrypting", e
}
encrypted
}
/**
* Creates a token.
* #return
*/
static String createToken(final String bookNumber, final String invNumber, final String cusNumber) {
String data = bookNumber + invNumber + cusNumber
String token = URLEncoder.encode(Base64.encodeBase64String(encrypt(data)), "UTF-8")
token
}
}
the error i get:
java.lang.IllegalStateException: Cipher not initialized
at javax.crypto.Cipher.checkCipherState(Cipher.java:1672)
at javax.crypto.Cipher.doFinal(Cipher.java:2079)
at javax.crypto.Cipher$doFinal$1.call(Unknown Source)

cipher.init method call is missed in your code. Check the below code.
public byte[] encrypt(byte[] data, byte[] key) {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key, "AES"));
return cipher.doFinal(data);
}
For decrypt have to change mode to Cipher.DECRYPT_MODE