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RC2 encryption results differences in Python and Java

For legacy compatibility I am being tasked with taking a 40 character value and adding 00000000 to the end and encrypting using RC2 in CBC Mode. I've been provided a 20 character key to use for encryption and a stand alone tool, written in Java, already being used to encrypt one 48 character string at a time. I am writing a script that will iterate through the list of 48 character values, encrypt each one, and then write it back to a table. I've tried to follow the Java code to replicate the process but am not getting the same results. Any help would be appreciated. Currently there is just one 48 character value in the list of values for testing. Later it will be pointed at an Oracle table for input and output:
value: e134db7b54ac00cb4236bb1be093e555613a54a600000000
key: 4757A2501EF662FD4C62
Python Result: EE2FCB7440EF47E55D4C01E8FCFF0069FB31438C4D69CA54
Java Result: F05CD7CD8906548C9B9FA2489D0B80A090BCF1D24FCE425B
Python:
from Cryptodome.Cipher import ARC2
values = ['e134db7b54ac00cb4236bb1be093e555613a54a600000000']
for value in values:
value = bytearray(value, 'ascii').decode('hex')
key = bytearray('4757A2501EF662FD4C62', 'ascii').decode('hex')
iv = '\x00\x00\x00\x00\x00\x00\x00\x00'
ef_keylen = 80
cipher = ARC2.new(key, ARC2.MODE_CBC, iv=iv, effective_keylen=ef_keylen)
encryptedvalue = cipher.encrypt(value)
encryptedvalue = encryptedvalue.encode('hex')
Java:
public static byte[] encrypt(String value, String rc2Key) throws Exception {
byte[] valueBytes = Hex.decodeHex(value.toCharArray());
byte[] rc2KeyBytes = Hex.decodeHex(rc2Key.toCharArray());
Key k = new SecretKeySpec(rc2KeyBytes, "RC2");
byte[] iv = {0,0,0,0,0,0,0,0};
RC2ParameterSpec spec = new RC2ParameterSpec(rc2Key.length() * 4, iv);
Cipher cipher = Cipher.getInstance("RC2/CBC/NoPadding");
cipher.init(Cipher.ENCRYPT_MODE, k, spec);
byte[] encrypted = cipher.doFinal(valueBytes);
return encrypted;
}
Why am I getting different encrypted values? What step am I missing. I'm fluent in Python or c# but am a novice with Java so am not sure where I am going wrong...

The code is good. I figured out that the values given to me were wrong for testing. I had to send the length of the key before decoding the hex value here:
cipher = ARC2.new(key, ARC2.MODE_CBC, iv=iv, effective_keylen=ef_keylen)
I corrected the cipher to:
cipher = ARC2.new(b_rc2key, ARC2.MODE_CBC, iv, effective_keylen=len(rc2key)*4)

JAVA DES Encryption Output Encoding

I have DES Encryption Algorithm implementation in JAVA (javax.crypto.Cipher), it is successfully encoding and decoding (most) strings... the problem is that, sometimes, it message specific blocks (since DES uses 8-character blocks in block mode).
In my case, almost always the 3rd block is messed up and rest shows fine.
for example:
key: thisiskey
message to encrypt: Google is an American multinational technology company specializing in Internet-related services
encrypted message (in UTF-8):
mñqè•ÀPŒ�øf"
ߦ\±õ¤ù'È9¢ëyT ÍQEÁ|;ëâÉ÷JWú
Now, when i go and decrypt this, i get this:
Decrypted message:
Google i,í\O¯‹Ýbº-¸�¬ltinational technology company specializHôJ—=ÊÍnternet-related services
As far as i understand the issue, it is due to the fact that UTF-8 CANNOT show all characters and thus, while showing as well as copying for decryption, this problem occurs.
Can anyone suggest me a solution?
Preferably, either a character-set that can handle this, or, a way to convert Binary directly to HEX (that can be output to user) and then Vice Versa (decrypted, after copying/pasting) in JAVA.
EDIT
This is 'approximate' code, not exact (for example encrypted message is not properly paste-able and these are parts of the function, but it should give the idea). Even in base64 encoding , i am unable to get this decrypted properly.
Encrypt Function code:
boolean base64 = true;
key = "thisiskey";
plainText = "Google is an American multinational technology company specializing in Internet-related services";
SecretKeyFactory MyKeyFactory = SecretKeyFactory.getInstance("DES");
byte[] keyBytes = key.getBytes();
DESKeySpec generatedKeySpec = new DESKeySpec(keyBytes);
SecretKey generatedSecretKey = MyKeyFactory.generateSecret(generatedKeySpec);
Cipher generatedCipher = Cipher.getInstance("DES");
generatedCipher.init(Cipher.ENCRYPT_MODE, generatedSecretKey);
byte[] messsageStringBytes = plainText.getBytes();
byte[] encryptedMessage = generatedCipher.doFinal(messsageStringBytes);
String encryptedMessageString = new String(encryptedMessage);
if (base64) {
encryptedMessageString = Base64.getEncoder().encodeToString(encryptedMessageString.getBytes("utf-8"));
}
return encryptedMessageString;
Decrypt Function code:
boolean dbase64 = true;
dkey = "thisiskey";
messageToDecrypt = "mñqè•ÀPŒ�øf\"ߦ\±õ¤ù'È9¢ëyT ÍQEÁ|;ëâÉ÷JWú"; // Message from above code
SecretKeyFactory MyKeyFactory = SecretKeyFactory.getInstance("DES");
byte[] dkeyBytes = dkey.getBytes();
DESKeySpec generatedKeySpec = new DESKeySpec(dkeyBytes);
SecretKey generatedSecretKey = MyKeyFactory.generateSecret(generatedKeySpec);
Cipher generatedCipher = Cipher.getInstance("DES");
generatedCipher.init(Cipher.DECRYPT_MODE, generatedSecretKey);
if (dbase64) {
byte[] decodedBytes = Base64.getDecoder().decode(dencryptedText);
dencryptedText = new String(decodedBytes, "utf-8");
}
byte[] messsageStringBytes = dencryptedText.getBytes();
byte[] encryptedMessage = generatedCipher.doFinal(messsageStringBytes);
String decryptedMessageString = new String(encryptedMessage);
return decryptedMessageString;

"Encrypted message in UTF-8" makes no sense. The ciphertext is binary and not UTF-8. You need to put it into a byte[], not a String.
If you need a String, use Base64 or Hex encoding.
Even in base64 encoding , i am unable to get this decrypted properly.
String encryptedMessageString = new String(encryptedMessage);
if (base64) {
encryptedMessageString = Base64.getEncoder().encodeToString(encryptedMessageString.getBytes("utf-8"));
}
That does not work. You are encoding to Base64 after the data is already broken (by calling new String). Do not put it in a String at all. Go directly from encryptedMessage (the byte[]) to Base64.

AES-256: IV vector misunderstanding between Ruby and Java implementations

I have "inherited" a Ruby on Rails app, and I must translate this app from Ruby to Java, and the most important thing, I don't have contact with the creator.
My problem is with the IV vector in AES-256 authentication. Ruby app uses AESCrypt gem to encrypt and decrypt user's password. It works fine, and I have already some thousands of users in DB.
The problem is when I try to do the same in Java (I've already updated JCE to allow 256bit key lenght). The Key and the IV are writen as binary strings in ruby source code (see bellow), and when I try to use it in Java I get a exception which say that the IV lenght must be 16 bytes long (I know that it must be 16 bytes long, but the binary string in Ruby has 32 characters).
Ruby code (works fine):
require 'openssl'
require 'digest/md5'
require 'base64'
module AESCrypt
KEY = "AB1CD237690AF13B6721AD237A"
IV = "por874hyufijdue7w63ysxwet4320o90"
TYPE = "AES-256-CBC"
def AESCrypt.key(key)
key = Digest::MD5.hexdigest(key)
key.slice(0..32)
end
# Encrypts a block of data given an encryption key and an
# initialization vector (iv). Keys, iv's, and the data returned
# are all binary strings. Cipher_type should be "AES-256-CBC",
# "AES-256-ECB", or any of the cipher types supported by OpenSSL.
# Pass nil for the iv if the encryption type doesn't use iv's (like
# ECB).
#:return: => String
#:arg: data => String
#:arg: key => String
#:arg: iv => String
#:arg: cipher_type => String
def AESCrypt.encrypt(data)
return nil if data.nil?
return data if data.blank?
aes = OpenSSL::Cipher::Cipher.new(TYPE)
aes.encrypt
aes.key = AESCrypt.key(KEY)
aes.iv = IV if IV != nil
result = aes.update(data) + aes.final
Base64.encode64(result)
end
end
and this is my Java code (it should do the same, seems that works with a 16 chars/bytes IV):
public static void main(String[] args) throws UnsupportedEncodingException {
String KEY = "AB1CD237690AF13B6721AD237A";
String IV = "por874hyufijdue7w63ysxwet4320o90";
SecretKeySpec key = generateKey(KEY);
String message = "password";
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
IvParameterSpec ivSpec = new IvParameterSpec(IV.getBytes());
cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);
byte[] ciphedText = cipher.doFinal(message.getBytes());
String encoded = Base64.encodeBase64String(ciphedText);
System.out.println("ENCRYPTED text= " + encoded);
}
public static SecretKeySpec generateKey(final String password) throws NoSuchAlgorithmException, UnsupportedEncodingException {
final MessageDigest digest = MessageDigest.getInstance("MD5");
byte[] bytes = password.getBytes("UTF-8");
digest.update(bytes, 0, bytes.length);
byte[] key = digest.digest();
SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
return secretKeySpec;
}
And I'm getting this exception (obviously):
java.security.InvalidAlgorithmParameterException: Wrong IV length: must be 16 bytes long
at com.sun.crypto.provider.CipherCore.init(CipherCore.java:516)
at com.sun.crypto.provider.AESCipher.engineInit(AESCipher.java:339)
at javax.crypto.Cipher.implInit(Cipher.java:801)
at javax.crypto.Cipher.chooseProvider(Cipher.java:859)
at javax.crypto.Cipher.init(Cipher.java:1370)
at javax.crypto.Cipher.init(Cipher.java:1301)
at com.javi.test.security.Test.main(Test.java:129)
I guess my problem is the way I convert the IV java string in byte[]. I think that openSSL code in ruby is unpacking (or doing something internally) the 32 bytes of the IV to 16 bytes. I have tried a lot of things, but I'm going crazy.
Anyone had the same problem or figure out where could be my problem?
I have posted the encryption code but I hace the same issue with decryption.
Thanks in advance, I'll be very grateful with every answer. :)

First, your IV is not actually iv, IV should be HEX encoded, but you have ASCII string "por874hyufijdue7w63ysxwet4320o90", may be it is some how encoded?
Second, IV.getBytes() will transofr IV's each character to hex encoding like p = 0x70, o = 0x6F, r = 0x72, etc...
It is not a useful answer, but may be hint.
Actually IV must be the same length as block cipher single block length. You have 32 bytes long IV itself, if you make IV.getBytes() IV length should match the cipher block length

AES128 Decryption :javax.crypto.badpaddingexception pad block corrupted

I try to decrypt an encrypted data that I receive from a web service.
The encryption is done using AES 128.
I use the following code to decrypt the data:
public static String decrypt(String strToDecrypt)
{
try
{
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding"); //AES/CBC/PKCS7Padding
SecretKeySpec secretKey = new SecretKeySpec(AppConstants.AESEncryptionKey.getBytes("UTF8"), "AES");
int blockSize = cipher.getBlockSize();
cipher.init(Cipher.DECRYPT_MODE, secretKey, new IvParameterSpec(new byte[blockSize])); //new IvParameterSpec(new byte[16])
byte decBytes[] = cipher.doFinal(Base64.decode(strToDecrypt, 0));
// byte decBytes[] = cipher.doFinal(Base64.decodeBase64(strToDecrypt));
String decStr = new String(decBytes);
System.out.println("After decryption :" + decStr);
return decStr;
}
catch (Exception e)
{
System.out.println("Exception in decryption : " + e.getMessage());
}
return null;
}
At
cipher.doFinal()
I got the following Exception:
javax.crypto.badpaddingexception pad block corrupted
I went through my post but ended up with no solution. I am badly stuck over here.

SecureRandom sr = SecureRandom.getInstance("SHA1PRNG","Crypto");
works perfectly
Note: This code works only on devices up to Android 6. Starting with Android 7.0 the "Crypto" provider has been removed, therefore this code will fail.

AES keys should consist of random data. If you store them as a String then you are likely to loose information, especially if you use encodings such as UTF-8. Your line:
AppConstants.AESEncryptionKey.getBytes("UTF8")
Makes it likely that you've lost data during conversion to/from a string. Use hexadecimals instead if you require a string, or simply store the key as a byte array.
Note that this answer doesn't indicate any security related hints. In general you only want to derive keys or store them in containers. You don't want to use CBC over an insecure channel either.

In my case issue is came because encrypted key and decrypted key both are different, when I check both key with same value then issue is not came

How can I decrypt in objective-c from a file encrypted by Java Cipher

I have an encrypt method in Java.
public static String encrypt(String orignal){
SecretKeySpec key = new SecretKeySpec(keyString.getBytes(), "AES");
IvParameterSpec initalVector = new IvParameterSpec(initialVectorParam.getBytes());
try{
Cipher cipher = Cipher.getInstance("AES/CFB8/NoPadding");
/////////////// encrypt /////////////////
cipher.init(Cipher.ENCRYPT_MODE, key, initalVector);
Log.d("AES", "oriByte: "+ orignal.getBytes());
int length = orignal.length();
for(int i=0; i<length; i++){
}
byte[] test = cipher.doFinal(orignal.getBytes());
Log.d("AES", "encByte: "+ test);
return bytes2Hex(test);
}catch (Exception e) {
Log.d("AES", "Encrypt Exception:"+orignal);
return "";
}
}
For compatibility with PHP, I use "AES/CFB8/NoPadding" options.
In PHP: $sCipher = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $sKey, $sStr, MCRYPT_MODE_CFB, $sIV);
And I have a Objective-c Cipher code from here.
https://gist.github.com/838614
I found that there is no IvParameterSpec in Objective-c Cipher like java.
Besides, the getBytes method returns a different value with java.
(I think this is because java uses different encoding way.)
So, how can I apply IvParameterSpec in Objective-c.
And is there any way to get 'getBytes' value like java in Objective-c?

For the initialization vector, see line 24 in your pastie:
NULL /* initialization vector (optional) */,
That's where you would pass your IV.
But without knowing the string encoding the Java code used to create the bytes used as the IV, you won't be able to seed the encryption properly to decrypt the data, even if you know what the string displays to the screen as. Put another way, just because the IV looks like "abc123" doesn't mean the bytes Java is writing to the IV buffer are going to be the same bytes you'll get if you strncpy() from a C character literal buffer. You have to agree on the encoding as part of the protocol for handling the data.
You will also need to agree on a key size. Your Java code does not specify how many bits are in the AES key.
Once you've got that worked out, you'll want to use a call like:
const void *key = /* KEY BYTES */;
const void *iv = /* IV BYTES */;
const void *text = /* CIPHER TEXT */;
size_t textlen = /*...*/;
size_t outlen = 0;
(void)CCCrypt(kCCDecrypt, kCCAlgorithmAES128, 0/*use CBC mode*/,
key, kCCKeySizeAES128, iv,
text, textlen,
&text, textlen, &outlen);
The plaintext will be written over the ciphertext, assuming all goes well. The amount o data written to text during decryption will be stored in outlen. Error checking is your responsibility; the header is well-commented.
Once you have the data, you'll want to slurp it into an NSString with the correct encoding (+[NSString initWithData:encoding:] would work), and then you have a string you can work with from Obj-C like any other string.