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Problem with ANSI Encoding file with Encryption in Linux, Java

I export a database with mysqldump a database in Ubuntu with java, then I encrypt and decrypt it with Java. I doing that with the following classes Encrypt and Decrypt with Java. But after the decryption some characters at the start of the file is wrong. Here is the problem:
At the first image is the file which programmatically have mysqldump, encrypt and decrypt. At the second one is just the mysqldump from the same command line. Can you point me the direction what to do? Thanks
EDIT
I have create a salt and stored it in a file like this:
Encryption:
FileInputStream saltFis = new FileInputStream("salt.enc");
byte[] salt = new byte[8];
saltFis.read(salt);
saltFis.close();
// reading the iv
FileInputStream ivFis = new FileInputStream("iv.enc");
byte[] iv = new byte[16];
ivFis.read(iv);
ivFis.close();
SecretKeyFactory factory = SecretKeyFactory.getInstance(secretAlgorithm1);
KeySpec keySpec = new PBEKeySpec(rsaSecret.toCharArray(), salt, 65536, 256);
SecretKey secretKey = factory.generateSecret(keySpec);
SecretKey secret = new SecretKeySpec(secretKey.getEncoded(), secretAlgorithm2);
//
Cipher cipher = Cipher.getInstance(algorithmEncryption);
cipher.init(Cipher.ENCRYPT_MODE, secret);
// file encryption
byte[] input = new byte[64];
int bytesRead;
while ((bytesRead = inFile.read(input)) != -1) {
byte[] output = cipher.update(input, 0, bytesRead);
if (output != null)
outFile.write(output);
}
byte[] output = cipher.doFinal();
if (output != null)
outFile.write(output);
inFile.close();
outFile.flush();
outFile.close();
Decryption:
FileInputStream saltFis = new FileInputStream("salt.enc");
byte[] salt = new byte[8];
saltFis.read(salt);
saltFis.close();
// reading the iv
FileInputStream ivFis = new FileInputStream("iv.enc");
byte[] iv = new byte[16];
ivFis.read(iv);
ivFis.close();
SecretKeyFactory factory = SecretKeyFactory.getInstance(secretAlgorithm1);
KeySpec keySpec = new PBEKeySpec(rsaSecret.toCharArray(), salt, 65536, 256);
SecretKey secretKey = factory.generateSecret(keySpec);
SecretKey secret = new SecretKeySpec(secretKey.getEncoded(), secretAlgorithm2);
// file decryption
Cipher cipher = Cipher.getInstance(algorithmEncryption);
cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));
FileInputStream fis = new FileInputStream(decodedB64);
FileOutputStream fos = new FileOutputStream(outputFile);
byte[] in = new byte[64];
int read;
while ((read = fis.read(in)) != -1) {
byte[] output = cipher.update(in, 0, read);
if (output != null)
fos.write(output);
}
byte[] output = cipher.doFinal();
if (output != null)
fos.write(output);
fis.close();
fos.flush();
fos.close();
System.out.println("File Decrypted.");

Oh, that one is simple. That idiotic (but funny enough, seeming largely correct otherwise) method of file encryption using CBC stores the IV in a separate file, overwriting any old one. So if you overwrite or take the wrong IV file then you'll get 16 random bytes at the start after decryption. So unless you can find the IV file that hopefully makes sense, your first 16 bytes (/characters) are now lost forever.
Of course, any sane encryption program stores the salt (a password & PBKDF2 is used for key derivation) and IV in the same file as the ciphertext.
Still, if you managed to lose the salt file or password then all the data would have been lost, so there's that...
With the added code the issue becomes even more clear. In the encryption mode you are forgetting to create & use an IvParameterSpec entirely during initialization:
cipher.init(Cipher.ENCRYPT_MODE, secret);
however, because of the way the IV data is read, you don't get any warning that the variable isn't used:
ivFis.read(iv);
If you would have created a nice method such as IvParameterSpec iv = readIvFromFile() then you would have caught this error.
Note that Java (by default in the included provider for Cipher) uses an all zero IV, so you're lucky and your data isn't partially gone.

How to handle BadPaddingException During AES256 encryption in C# and decryption in Java

I don't know why an error is coming up.
Exception in thread "main" javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can arise if a bad key is used during decryption.
I understand that this error occurs when the incorrect key is used during the decryption. However, if you look at the test results result below, you can see that both C# and Java are the same (Key, IV, Salt is Base64 encoded).
C# Test Result
Java Test Result
It's the same!(Key, IV, Salt)
But the current BadpaddingException error is generated. What could be the problem?
I am attaching my source file.
C# (Encryption)
class AES {
private readonly static string keyStr = "This is Key";
private readonly static string vector = "This is Vector";
public static Rfc2898DeriveBytes MakeKey(string password){
byte[] keyBytes = System.Text.Encoding.UTF8.GetBytes(password);
byte[] saltBytes = SHA512.Create().ComputeHash(keyBytes);
Rfc2898DeriveBytes result = new Rfc2898DeriveBytes(keyBytes, saltBytes, 65536);
return result;
}
public static Rfc2898DeriveBytes MakeVector(string vector){
byte[] vectorBytes = System.Text.Encoding.UTF8.GetBytes(vector);
byte[] saltBytes = SHA512.Create().ComputeHash(vectorBytes);
Rfc2898DeriveBytes result = new Rfc2898DeriveBytes(vectorBytes, saltBytes, 65536);
return result;
}
public static void Encrypt(String inputFile, String outputFile) {
using (RijndaelManaged aes = new RijndaelManaged()){
//Create Key and Vector
Rfc2898DeriveBytes key = AES.MakeKey(AES.keyStr);
Rfc2898DeriveBytes vector = AES.MakeVector(AES.vector);
//AES256
aes.BlockSize = 128;
aes.KeySize = 256;
// It is equal in java
// Cipher _Cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.PKCS7;
aes.Key = key.GetBytes(32); //256bit key
aes.IV = vector.GetBytes(16); //128bit block size
//processing Encrypt
ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
byte[] encrypted;
using (MemoryStream msEncrypt = new MemoryStream()) {
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write)) {
byte[] inputBytes = File.ReadAllBytes(inputFile);
csEncrypt.Write(inputBytes, 0, inputBytes.Length);
}
encrypted = msEncrypt.ToArray();
}
string encodedString = Convert.ToBase64String(encrypted);
File.WriteAllText(outputFile, encodedString);
}
}
}
Java (Decryption)
public class AES256File {
private static final String algorithm = "AES";
private static final String blockNPadding = algorithm+"/CBC/PKCS5Padding";
private static final String password = "This is Key";
private static final String IV = "This is Vector";
private static IvParameterSpec ivSpec;
private static Key keySpec;
public static void MakeKey(String password) throws NoSuchAlgorithmException, UnsupportedEncodingException, InvalidKeySpecException{
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
MessageDigest digest = MessageDigest.getInstance("SHA-512");
byte[] keyBytes = password.getBytes("UTF-8");
// C# : byte[] saltBytes = SHA512.Create().ComputeHash(keyBytes);
byte[] saltBytes = digest.digest(keyBytes);
//256bit
PBEKeySpec pbeKeySpec = new PBEKeySpec(password.toCharArray(), saltBytes, 65536, 256);
Key secretKey = factory.generateSecret(pbeKeySpec);
byte[] key = new byte[32];
System.arraycopy(secretKey.getEncoded(), 0, key, 0, 32);
SecretKeySpec secret = new SecretKeySpec(key, "AES");
setKeySpec(secret);
}
public static void MakeVector(String IV) throws NoSuchAlgorithmException, UnsupportedEncodingException, InvalidKeySpecException{
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
MessageDigest digest = MessageDigest.getInstance("SHA-512");
byte[] vectorBytes = IV.getBytes("UTF-8");
byte[] saltBytes = digest.digest(vectorBytes);
// 128bit
PBEKeySpec pbeKeySpec = new PBEKeySpec(IV.toCharArray(), saltBytes, 65536, 128);
Key secretIV = factory.generateSecret(pbeKeySpec);
byte[] iv = new byte[16];
System.arraycopy(secretIV.getEncoded(), 0, iv, 0, 16);
IvParameterSpec ivSpec = new IvParameterSpec(iv);
setIvSpec(ivSpec);
}
public void decrypt(File source, File dest) throws Exception {
Cipher c = Cipher.getInstance(blockNPadding);
c.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
fileProcessing(source, dest, c);
}
public void fileProcessing(File source, File dest, Cipher c) throws Exception{
InputStream input = null;
OutputStream output = null;
try{
input = new BufferedInputStream(new FileInputStream(source));
output = new BufferedOutputStream(new FileOutputStream(dest));
byte[] buffer = new byte[input.available()];
int read = -1;
while((read = input.read(buffer)) != -1){
output.write(c.update(buffer, 0, read));
}
byte[] deryptedBytes = c.doFinal(buffer); // -----------------------> Error!! Showing!
byte[] decodedBytes = Base64.getDecoder().decode(deryptedBytes);
String decodeString = new String(decodedBytes, "UTF-8");
decodedBytes = decodeString.getBytes(StandardCharsets.UTF_8);
output.write(decodedBytes);
}finally{
if(output != null){
try{output.close();}catch(IOException e){}
}
if(input != null){
try{input.close();}catch(IOException e){}
}
}
}
I have verified as below.
Verification Key and IV in C#
//Key Verification
var salt = Convert.ToBase64String(saltBytes);
Console.Write("Salt Result : ");
Console.WriteLine(salt);
var result_test = Convert.ToBase64String(result.GetBytes(32));
Console.Write("Key Test Result: ");
Console.WriteLine(result_test);
//IV Verification (Salt is Using same code)
var result_test = Convert.ToBase64String(result.GetBytes(16));
Console.Write("IV Test Result: ");
Console.WriteLine(result_test);
Verification Key and IV in Java
//Key Verification
/* print Salt */
String base64 = Base64.getEncoder().encodeToString(saltBytes);
System.out.println("Salt Result : " + base64);
/* print Key */
String result_test = Base64.getEncoder().encodeToString(key);
System.out.println("Key Test Result : " + result_test);
/* print generated Key */
System.out.println("Secret Key Result : " + Base64.getEncoder().encodeToString(secret.getEncoded()));
//IV Verification (Salt is Using same code)
/* print IV */
String result_test = Base64.getEncoder().encodeToString(iv);
System.out.println("IV Test Result : " + result_test);
/* print generated IV */
System.out.println("IV Result : " + Base64.getEncoder().encodeToString(ivSpec.getIV()));
Updated
c# .netframework 4.5 / Java8 modified what #Topaco said and confirmed that it worked well.
I want to say thank you very much to #Topaco and #Gusto2, and I'm going to make changes to the parts that have been modified in security, just as #Gusto2 said!

1) In the C# Encrypt-method the plain text is encrypted first and then Base64-encoded. Thus, in the decryption process the data must be Base64-decoded first and then decrypted. Currently this is handled in the wrong order i.e. the data are decrypted first and then decoded. Therefore, in the Java fileProcessing-method replace
while((read = input.read(buffer)) != -1){
output.write(c.update(buffer, 0, read));
}
with
while((read = input.read(buffer)) != -1) {
byte[] bufferEncoded = buffer;
if (read != buffer.length) {
bufferEncoded = Arrays.copyOf(buffer, read);
}
byte[] bufferDecoded = Base64.getDecoder().decode(bufferEncoded);
output.write(c.update(bufferDecoded));
}
2) It's not necessary to pass buffer (or bufferDecoded) to the doFinal-method, since that was already done in the update-method. Thus,
byte[] deryptedBytes = c.doFinal(buffer);
must be replaced with
output.write(c.doFinal());
3) Since the Base64-decoding is already done in 1) in the try-block all lines following the doFinal-statement have to be removed. Overall, this results in
try {
input = new BufferedInputStream(new FileInputStream(source));
output = new BufferedOutputStream(new FileOutputStream(dest));
byte[] buffer = new byte[input.available()];
int read = -1;
while((read = input.read(buffer)) != -1) {
byte[] bufferEncoded = buffer;
if (read != buffer.length) {
bufferEncoded = Arrays.copyOf(buffer, read);
}
byte[] bufferDecoded = Base64.getDecoder().decode(bufferEncoded);
output.write(c.update(bufferDecoded));
}
output.write(c.doFinal());
}
4) The size of the buffer has to be a multiple of 4 in order to ensure a proper Base64-decoding. Thus, it's more reliable to replace
byte[] buffer = new byte[input.available()];
with
byte[] buffer = new byte[4 * (input.available() / 4)];
As long as the data are read in one chunk (which is not guaranteed, see e.g. https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/io/InputStream.html#available()) there is no problem. However, if the data are read in several chunks it's important to read a multiple of 4 bytes, otherwise the Base64-decoding will fail. That can be easily proved by using a buffer size which isn't a multiple of 4. This point must also be considered if the buffer size is explicitly defined with regard to larger files.

while((read = input.read(buffer)) != -1){
output.write(c.update(buffer, 0, read));
}
byte[] deryptedBytes = c.doFinal(buffer)
you are decrypting the input to a file, then you are using the same cipher instance to decrypt the the last read chunk (again) into a separate array not to the file
quick fix:
while((read = input.read(buffer)) != -1){
output.write(c.update(buffer, 0, read));
}
output.write(c.doFinal()); // write the padded block
if you want to create and print a decrypted String, you need to create a new Cipher instance (or maybe it will be enough to reinitialize the instance, I am not sure) assuming the buffer contains the whole input
c.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
// assuming the buffer contains the whole input again
byte[] deryptedBytes = c.doFinal(buffer); // decrypting the whole file again
correct approach:
IV is used to securely reuse the same encryption key for multiple encryptions. So if your key is not random, you should generate new random IV for each encryption (and pass the IV along the ciphertext, most often prepended). Otherwise the encryption is not semantically secure and you may create opening for the two pad attack. So deriving IV from the key may not be very secure.
I advice to use any MAC (authentication code) passed along the ciphertext to ensure integrity (e.g. HMAC)
you are still reading all the file input fully into memory, what would not work for REALLY LARGE files. You may initialize the buffer to an arbitrary length (a few MB?) and process the input file as chunked

incomplete RSA decryption with large XML file type - JAVA

I have a problem when decrypting XML type my file my returns incomplete data algorithm and rare symbols.
public File decryptFile(File fileInput, X509Certificate certificate) throws BadPaddingException, Exception {
try (DataInputStream dis = new DataInputStream(new FileInputStream(fileInput))) {
byte[] encryptedKeyBytes = new byte[dis.readInt()];
dis.readFully(encryptedKeyBytes);
PublicKey publicKey = certificate.getPublicKey();
rsaCipher.init(Cipher.DECRYPT_MODE, publicKey);
byte[] rijndaelKeyBytes = rsaCipher.doFinal(encryptedKeyBytes);
SecretKey rijndaelKey = new SecretKeySpec(rijndaelKeyBytes, "Rijndael");
byte[] iv = new byte[16];
dis.read(iv);
IvParameterSpec spec = new IvParameterSpec(iv);
Cipher cipher = Cipher.getInstance("Rijndael/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, rijndaelKey, spec);
try (CipherInputStream cis = new CipherInputStream(dis, cipher)) {
try (FileOutputStream fos = new FileOutputStream(fileInput.getAbsolutePath() + ".xml")) {
byte[] data = new byte[16];
int theByte;
while ((theByte = cis.read(data)) != -1) {
System.out.print(new String(data));
fos.write(data, 0, theByte);
}
System.out.println("\n\n");
}
}
}
return new File(fileInput.getAbsolutePath() + ".xml");
}
this code returns me the data
</ctaAbonBenef><distPago>00000</distPago><item>00000</item><pagoPoder>N</p�|���[�[W�Z�5��Q�
I think this has to do with UTF-8, but I can not solve.
Now I can also believe that it is the encryption algorithm to use, I leave just in case.
public static void generateFileEncrypt(File fileInput, PrivateKey privateKey, String folderSave) throws Exception {
String fileOutput = folderSave + "\" + fileInput.getName() + ENCRYPTED_FILENAME_SUFFIX;
DataOutputStream output = new DataOutputStream(new FileOutputStream(fileOutput));
Cipher rsaCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
rsaCipher.init(Cipher.ENCRYPT_MODE, privateKey);
KeyGenerator rijndaelKeyGenerator = KeyGenerator.getInstance("Rijndael");
rijndaelKeyGenerator.init(128);
Key rijndaelKey = rijndaelKeyGenerator.generateKey();
byte[] encodedKeyBytes = rsaCipher.doFinal(rijndaelKey.getEncoded());
output.writeInt(encodedKeyBytes.length);
output.write(encodedKeyBytes);
SecureRandom random = new SecureRandom();
byte[] iv = new byte[16];
random.nextBytes(iv);
output.write(iv);
IvParameterSpec spec = new IvParameterSpec(iv);
Cipher symmetricCipher = Cipher.getInstance("Rijndael/CBC/PKCS5Padding");
symmetricCipher.init(Cipher.ENCRYPT_MODE, rijndaelKey, spec);
try (
CipherOutputStream cos = new CipherOutputStream(output, symmetricCipher);
FileInputStream fis = new FileInputStream(fileInput)) {
int theByte;
byte[] data = new byte[16];
while ((theByte = fis.read(data)) != -1) {
System.out.print(new String(data));
cos.write(data, 0, theByte);
}
System.out.println("\n\n");
cos.flush();
}
}
Thanks in advance.

I haven't digested all your code; I stopped when I saw you trying to decrypt with the public key, and encrypting with the private key. That's sort of like a digital signature, but your padding will be all wrong and you should use the Signature class if that is what your really want to do.
The public key is used to encrypt, or to verify a digital signature. Use the private key to decrypt, and see if that resolves your problem.
You are still doing it wrong. Don't call it "encryption" if the key isn't private.
But anyway, I think the printing to stdout looks wrong because you are converting the entire buffer to text. The last block is likely to be padded, so it won't decode to valid text—it's padding; it wasn't part of the input file, and you aren't writing it to the decrypted file, but you are printing it.
Change to encrypt with the public key, decrypt with the private key, and then change your printing to this:
System.out.print(new String(data, 0, theByte));
Even better would be to specify the character set of the data (probably UTF-8, since it's the default for XML).

I think u should do the opposite. encrypt with the public key and decrypt with the private key..

RSA keyblock wrapper: javax.crypto.BadPaddingException: Decryption error

In a larger application doing other things - I need to encrypt and decrypt a file. So I have been looking around and have implemented these two core functions that basically use RSA keys to wrap a random AES key that encrypts a file. The symmetric key and iv are written to the start of the file.
I'm getting an exception ("javax.crypto.BadPaddingException: Decryption error") in the decrypt function portion of below. On the unpackKeyandIV line -- the doFinal. Specifically this line is the Exception point:
Object[] keyIv = unpackKeyAndIV(xCipher.doFinal(keyBlock));
I've checked and remade the RSA key pairs. I've also checked the save/load of the keyBlock.
My gut is the problem has something to do with how I write/read the keyBlock --- or encoding perhaps?
One goal is to keep the RSA/AES instance as generic as possible so as not to need Bouncy Castle or extra Java security unlimited strength extensions.
Any thoughts on where I might be going wrong.
Thanks in advance.
[Final update: This code below is working. Error was passing in a corrupted privKey]
// RSA_INSTANCE = "RSA";
// ASSYM_CRYPTO_STR = 1024;
// SYM_CRYPTO_STR = 128;
// SYM_CRYPTO = "AES";
// AES_INSTANCE = "AES/CTR/NoPadding";
//
// File in = plain input file
// File out = encrypted output file
// Key pubKey = public Key (that wraps a random AES key)
public static void encryptFile(File in, File out, Key pubKey) throws Exception {
FileInputStream fin;
FileOutputStream fout;
int nread = 0;
byte[] inbuf = new byte[1024];
fout = new FileOutputStream(out);
fin = new FileInputStream(in);
SecureRandom random = new SecureRandom();
// symmetric wrapping
Key sKey = createKeyForAES(Config.SYM_CRYPTO_STR, random);
IvParameterSpec sIvSpec = createCtrIvForAES(0, random);
// encrypt symmetric key with RSA/pub key
Cipher xCipher = Cipher.getInstance(Config.RSA_INSTANCE);
xCipher.init(Cipher.ENCRYPT_MODE, pubKey, random);
byte[] keyBlock = xCipher.doFinal(packKeyAndIv(sKey, sIvSpec));
fout.write(keyBlock);
// encrypt data with symmetric key
Cipher sCipher = Cipher.getInstance(Config.AES_INSTANCE);
sCipher.init(Cipher.ENCRYPT_MODE, sKey, sIvSpec);
// Now read our file and encrypt it.
while((nread = fin.read(inbuf)) > 0) {
fout.write(sCipher.update(inbuf, 0, nread)); // cannot be null, by construction
}
// NB doFinal() cannot return null, but can return a zero-length array, which is benign below.
fout.write(sCipher.doFinal());
fout.flush();
fin.close();
fout.close();
}
// Decrypt File
public static void decryptFile(File in, File out, Key privKey) throws Exception {
FileInputStream fin;
FileOutputStream fout;
int nread = 0;
byte[] inbuf = new byte[1024];
fout = new FileOutputStream(out);
fin = new FileInputStream(in);
byte[] keyBlock = new byte[128];
nread = fin.read(keyBlock);
Cipher xCipher = Cipher.getInstance(Config.RSA_INSTANCE);
Cipher sCipher = Cipher.getInstance(Config.AES_INSTANCE);
// symmetric key/iv unwrapping step
xCipher.init(Cipher.DECRYPT_MODE, privKey);
Object[] keyIv = unpackKeyAndIV(xCipher.doFinal(keyBlock));
// decryption step
sCipher.init(Cipher.DECRYPT_MODE, (Key)keyIv[0], (IvParameterSpec)keyIv[1]);
while((nread = fin.read(inbuf)) >0) {
fout.write(sCipher.update(inbuf,0,nread));
}
fout.write(sCipher.doFinal());
fout.flush();
fin.close();
fout.close();
}
public static byte[] packKeyAndIv(Key key, IvParameterSpec ivSpec) throws IOException {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
bOut.write(ivSpec.getIV());
bOut.write(key.getEncoded());
return bOut.toByteArray();
}
public static Object[] unpackKeyAndIV(byte[] data) {
byte[] keyD = new byte[16];
byte[] iv = new byte[data.length - 16];
return new Object[] {
new SecretKeySpec(data, 16, data.length - 16, "AES"),
new IvParameterSpec(data, 0, 16)
};
}

Per edits and comments. Error was a corrupted privKey being passed into the decrypt function. Above code works fine.

try adding the following under your constructor -
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

RSA AES decryption fails - InvalidKeyException

I have been able to use the algorithm to encrypt and decrypt files , but when I go to try and send a file from Android to a WAS server, it fails. Here is the encrypt side
Security.addProvider(new BouncyCastleProvider());
KeyGenerator keygen = KeyGenerator.getInstance("AES");
SecureRandom random = new SecureRandom();
keygen.init(random);
SecretKey key = keygen.generateKey();
// wrap with RSA public key
ObjectInputStream keyIn = new ObjectInputStream(new FileInputStream (getFileLocation(PUBLIC_KEY, localTest)));
Key publicKey = (Key) keyIn.readObject();
keyIn.close();
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.WRAP_MODE, publicKey);
byte[] wrappedKey = cipher.wrap(key);
DataOutputStream out = new DataOutputStream(new FileOutputStream(getFileLocation(SIGN_FILE, localTest)));
out.writeInt(wrappedKey.length);
out.write(wrappedKey);
InputStream in = new ByteArrayInputStream(message.getBytes());
cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, key);
crypt(in, out, cipher);
in.close();
out.close();
FileInputStream fis = new FileInputStream(getFileLocation(SIGN_FILE, localTest));
byte[] buffer = new byte[fis.available()];
int i =0;
while (i< buffer.length ){
buffer[i]= (byte)fis.read();
i++;
}
String ss = encodeMsg(buffer);
return ss;
Here is the decrypt side
Security.addProvider(new BouncyCastleProvider());
byte[] arr = decodeMsg(encrypted);
DataInputStream in = new DataInputStream(new ByteArrayInputStream(arr));
int length = in.readInt();
byte[] wrappedKey = new byte[length];
in.read(wrappedKey, 0, length);
// unwrap with RSA private key
ObjectInputStream keyIn = new ObjectInputStream(new FileInputStream (getFileLocation(PRIVATE_KEY, localTest)));
Key privateKey = (Key) keyIn.readObject();
keyIn.close();
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.UNWRAP_MODE, privateKey);
Key key = cipher.unwrap(wrappedKey, "AES", Cipher.SECRET_KEY);
OutputStream out = new FileOutputStream(getFileLocation(DECRYPTED, localTest));
cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, key);
crypt(in, out, cipher);
in.close();
out.close();
FileInputStream fis = new FileInputStream(getFileLocation(DECRYPTED, localTest));
byte[] buffer = new byte[fis.available()];
int i =0;
while (i< buffer.length ){//!= 0) {
buffer[i]= (byte)fis.read();
i++;
}
String ss = new String(buffer);
return ss;
Again, on my workstation, this works. When doing the mobile request to the WAS web server, it fails. At first, it argued with the object class and so I recreated the keys using Java 1.6. I have recompiled the war into Java 1.6 as well. It errors as below.
--cipher unwrap
java.security.InvalidKeyException com.ibm.crypto.provider.RSA.engineUnwrap(Unknown Source)
javax.crypto.Cipher.unwrap(Unknown Source)
com.webapp.web.security.RSAEncrypt.decrypt(RSAEncrypt.java:161)
com.webapp.web.MobileRequest.doPost(MobileRequest.java:81)
javax.servlet.http.HttpServlet.service(HttpServlet.java:738)
javax.servlet.http.HttpServlet.service(HttpServlet.java:831)
...
Does the WAS environment have to be updated to handle this? ideas?
UPDATE the keysize is set to 2048

This could be due to key policy settings, do you have the Unlimited Strength Juristiction Policies installed on both machines? They can be found at the bottom of this page: http://www.oracle.com/technetwork/java/javase/downloads/index.html
Else, how are you sending the data to the server?

The Unlimited Jurisdiciton policy might work, but I attempted to use the IBMJCE without success as well. Then, I switched to use the SunJCE provider (version Java 1.6) and now I am able to do the encryption and decryption in both Android and Websphere. I am having the administrators look into the policy files to see if BouncyCastle could be enabled, but I am ok with using the Sun provider files.