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how to use password with PBEKeySpec hash

I'm working on an embedded application, and I need to decrypt a message using PBEKeySpec, since the password is a hash, I don't know if the algorithm is correct, because I always have a return similar to this: '?s.PH ?~+? ?*ol XL >?? ;#??????'
public static String decrypt(String encrypted) throws Exception {
byte[] original = null;
try {
char[] pw = getSecret().toCharArray();
byte[] salt = new byte[]{1, 2, 3, 4, 5, 6, 7, 8};
PBEKeySpec pbeKeySpec = new PBEKeySpec(pw, salt, 1000, 384);
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
SecretKey secretKey = factory.generateSecret(pbeKeySpec);
byte[] key = new byte[32];
byte[] iv = new byte[16];
System.arraycopy(secretKey.getEncoded(), 0, key, 0, 32);
System.arraycopy(secretKey.getEncoded(), 32, iv, 0, 16);
SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
AlgorithmParameterSpec ivSpec = new IvParameterSpec(iv);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivSpec);
original = cipher.doFinal(encrypted.getBytes());
} catch (Exception ex) {
ex.printStackTrace();
}
return new String(original, StandardCharsets.US_ASCII);
}
To generate the password hash:
private static String getSecret() {
StringBuffer hexString = new StringBuffer();
try {
MessageDigest digest = MessageDigest.getInstance("SHA-256");
byte[] hash = digest.digest(Arrays.copyOf(secret.getBytes(), 36));
for (int i = 0; i < hash.length; i++) {
String hex = Integer.toHexString(0xff & hash[i]);
if (hex.length() == 1) {
hexString.append('0');
}
hexString.append(hex);
}
} catch (Exception ex) {
Logger.getLogger(CriptografiaHelper.class.getName()).log(Level.SEVERE, null, ex);
}
return hexString.toString();
}

Java Cipher Decryption on large files

I am trying to decrypt files by Java and below codes work. However it will have OutOfMemory exception when decrypting large files. I tried to change to cipher.update but the program will freeze without any responding.
How can I change this from doFinal to update?
public File decryptDataFile(File inputFile, File outputFile, File keyFile, String correlationId) {
try {
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] byteInput = this.getFileInBytes(inputFile);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "BC");
byte[] salt = new byte[8];
System.arraycopy(byteInput, 8, salt, 0, 8);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
cipher.init(Cipher.DECRYPT_MODE, fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100)));
byte[] data = cipher.doFinal(byteInput, 16, byteInput.length-16);
OutputStream os = new FileOutputStream(outputFile);
os.write(data);
os.close();
if(outputFile.exists()) {
return outputFile;
} else {
return null;
}
} catch (IOException | NoSuchAlgorithmException | NoSuchProviderException | NoSuchPaddingException | InvalidKeyException | InvalidKeySpecException | IllegalBlockSizeException | BadPaddingException e) {
logger.WriteLog(appConfig.getPlatform(), "INFO", alsConfig.getProjectCode(), correlationId, alsConfig.getFunctionId(), "SCAN_DECRYPT", e.getClass().getCanonicalName() + " - " + e.getMessage() );
return null;
}
}
My non-working version:
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] byteInput = this.getFileInBytes(inputFile);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "BC");
byte[] salt = new byte[8];
System.arraycopy(byteInput, 8, salt, 0, 8);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
cipher.init(Cipher.DECRYPT_MODE, fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100)));
FileInputStream fis = new FileInputStream(inputFile);
FileOutputStream fos = new FileOutputStream(outputFile);
CipherInputStream cis = new CipherInputStream(fis, cipher);
int b;
byte[] d = new byte[8];
while((b = cis.read(d)) != -1) {
fos.write(d, 0, b);
}
fos.flush();
fos.close();
cis.close();
if(outputFile.exists()) {
return outputFile;
} else {
return null;
}

Foreword: I couldn't decrypt with your original method a file that was encrypted with your openssl-command
openssl enc -aes-256-cbc -e -salt -in ${tarFile} -out ${encTarFile} -pass file:./${KEY_RANDOM}
but the following method should decode even large files similar to your original method - I tested files up to 1 GB size.
Edit: Regarding the OpenSSL statement, it's worth mentioning that since v1.1.0 the default digest has changed from MD5 to SHA256,
so for higher versions the -md MD5 option must be set explicitly for compatibility with the Java code. (thanks to #Topaco).
Please keep in mind that I don't care about correct file paths for
new FileInputStream(inputFile.toPath().toString())
and
new FileOutputStream(outputFile.toPath().toString())
as I'm working locally and with my folder, maybe you have to change the code to "find" your files. As well there is no exception handling in this example.
The code line
byte[] ibuf = new byte[8096];
is defining the buffer that is used - a larger buffer makes the decryption faster but consumes more memory (8096 means 8096 byte compared to 1 Gbyte when reading the complete file into memory and causing the out of memory error).
public static File decryptDataFileBuffered(File inputFile, File outputFile, File keyFile, String correlationId) throws IOException, NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, BadPaddingException, IllegalBlockSizeException, InvalidKeyException {
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] salt = new byte[8];
byte[] salted = new byte[8]; // text SALTED__
try (FileInputStream in = new FileInputStream(inputFile.toPath().toString()); // i don't care about the path as all is lokal
FileOutputStream out = new FileOutputStream(outputFile.toPath().toString())) // i don't care about the path as all is lokal
{
byte[] ibuf = new byte[8096]; // thats the buffer used - larger is faster
int len;
in.read(salted);
in.read(salt);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
SecretKey secretKey = fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100));
System.out.println("secretKey length: " + secretKey.getEncoded().length + " data: " + bytesToHex(secretKey.getEncoded()));
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secretKey);
while ((len = in.read(ibuf)) != -1) {
byte[] obuf = cipher.update(ibuf, 0, len);
if (obuf != null)
out.write(obuf);
}
byte[] obuf = cipher.doFinal();
if (obuf != null)
out.write(obuf);
} catch (IOException | BadPaddingException | IllegalBlockSizeException e) {
e.printStackTrace();
}
if (outputFile.exists()) {
return outputFile;
} else {
return null;
}
}
Edit2: As commented by #Topaco the usage of CipherInput/OutputStream shortens the code and makes it better readable, so here is the code:
public static File decryptDataFileBufferedCipherInputStream (File inputFile, File outputFile, File keyFile, String correlationId) throws
IOException, NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException
{
Security.addProvider(new BouncyCastleProvider());
String key = new String(Files.readAllBytes(keyFile.toPath())).trim();
byte[] salt = new byte[8];
byte[] salted = new byte[8]; // text SALTED__
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
try (FileInputStream in = new FileInputStream(inputFile.toPath().toString()); // i don't care about the path as all is lokal
CipherInputStream cipherInputStream = new CipherInputStream(in, cipher);
FileOutputStream out = new FileOutputStream(outputFile.toPath().toString())) // i don't care about the path as all is lokal
{
byte[] buffer = new byte[8192];
in.read(salted);
in.read(salt);
SecretKeyFactory fact = SecretKeyFactory.getInstance("PBEWITHMD5AND256BITAES-CBC-OPENSSL", "BC");
SecretKey secretKey = fact.generateSecret(new PBEKeySpec(key.toCharArray(), salt, 100));
System.out.println("secretKey length: " + secretKey.getEncoded().length + " data: " + bytesToHex(secretKey.getEncoded()));
cipher.init(Cipher.DECRYPT_MODE, secretKey);
int nread;
while ((nread = cipherInputStream.read(buffer)) > 0) {
out.write(buffer, 0, nread);
}
out.flush();
}
if (outputFile.exists()) {
return outputFile;
} else {
return null;
}
}

javax.crypto.BadPaddingException: Given final block not properly padded - AES/CBC/PKCS5PADDING

I am trying to write an encryption/decryption utility class, but not matter what I do I cannot seem to get decryption working. I keep getting a javax.crypto.BadPaddingException: Given final block not properly padded exception during decryption.
I've looked at a number of examples and other stack overflow questions but can't seem to find my mistake
public class EncryptionUtil {
private static final Log LOGGER = LogFactory.getLog(EncryptionUtil.class);
private static final String CIPHER_MODE = "AES/CBC/PKCS5PADDING";
private static final String CRYPTO_PROPERTIES_PATH = "/crypto.properties";
private static final SecretKeySpec sKey = keySpecFromProperties();
private EncryptionUtil() {}
public static byte[] encrypt(byte[] aBytes) {
try {
SecureRandom lSecureRandom = new SecureRandom();
byte[] ivBytes = new byte[16];
lSecureRandom.nextBytes(ivBytes);
IvParameterSpec lSpec = new IvParameterSpec(ivBytes);
Cipher cipher = Cipher.getInstance(CIPHER_MODE);
cipher.init(Cipher.ENCRYPT_MODE, sKey, lSpec);
byte[] encryptedBytes = cipher.doFinal(aBytes);
byte[] outBytes = new byte[encryptedBytes.length + 16];
System.arraycopy(ivBytes, 0, outBytes, 0, 16);
System.arraycopy(encryptedBytes, 0, outBytes, 16, encryptedBytes.length);
return outBytes;
} catch (Exception aEx) {
LOGGER.error("Failed to encrypt bytes");
throw new RuntimeException(aEx);
}
}
public static byte[] decrypt(byte[] aBytes) {
try {
byte[] lIvBytes = Arrays.copyOfRange(aBytes, aBytes.length - 16, aBytes.length);
byte[] lEncryptedBytes = Arrays.copyOfRange(aBytes, 0, aBytes.length - 16);
IvParameterSpec lIvSpec = new IvParameterSpec(lIvBytes);
Cipher cipher = Cipher.getInstance(CIPHER_MODE);
cipher.init(Cipher.DECRYPT_MODE, sKey, lIvSpec);
return cipher.doFinal(lEncryptedBytes);
}catch (Exception aEx){
LOGGER.error("Failed to decrypt bytes. Returning input bytes", aEx);
return aBytes;
}
}
private static SecretKeySpec keySpecFromProperties(){
try(InputStream lPropStream = EncryptionUtil.class.getResourceAsStream(CRYPTO_PROPERTIES_PATH)){
Properties cryptoProps = new Properties();
cryptoProps.load(lPropStream);
String lSecret = cryptoProps.getProperty("secret");
MessageDigest digest = MessageDigest.getInstance("SHA-256");
digest.update(lSecret.getBytes("UTF-8"));
byte[] keyBytes = new byte[16];
System.arraycopy(digest.digest(),0, keyBytes, 0, keyBytes.length);
return new SecretKeySpec(keyBytes, "AES");
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}

You prepend your IV to the ciphertext on encryption, but on decryption you copy the last 16 bytes as your IV.
Whatever you do on encryption you must undo on decryption.

Java 1.8 symmetric DESede encryption and decryption [duplicate]

I have a hardcoded key with which I want to encrypt a string before storing it in SharedPreferences. This is the code I have so far:
public class TokenEncryptor {
private final static String TOKEN_KEY = "91a29fa7w46d8x41";
public static String encrypt(String plain) {
try {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
AlgorithmParameterSpec ivSpec = new IvParameterSpec(new byte[16]);
SecretKeySpec newKey = new SecretKeySpec(TOKEN_KEY.getBytes(), "AES");
cipher.init(Cipher.ENCRYPT_MODE, newKey, ivSpec);
return new String(cipher.doFinal(plain.getBytes()));
} catch (Exception e) {
Ln.e(e);
return null;
}
}
public static String decrypt(String encoded) {
try {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
AlgorithmParameterSpec ivSpec = new IvParameterSpec(new byte[16]);
SecretKeySpec newKey = new SecretKeySpec(TOKEN_KEY.getBytes(), "AES");
cipher.init(Cipher.DECRYPT_MODE, newKey, ivSpec);
return new String(cipher.doFinal(encoded.getBytes()));
} catch (Exception e) {
Ln.e(e);
return null;
}
}
}
It seems to be catching an exception at the end of decrypt method:
javax.crypto.IllegalBlockSizeException: error:0606506D:digital envelope routines:EVP_DecryptFinal_ex:wrong final block length
Can someone point me in the right direction? I have a feeling I'm doing something wrong instantiating IvParameterSpec.

When you encrypt a string with AES, you get an array of bytes back. Trying to convert those bytes directly to a string (new String(cipher.doFinal(plaintextBytes))) will cause all sorts of problems. If you require the output from your encryption method to be a string, then use Base64 rather than attempting a direct conversion. In your decryption method, convert the Base64 string back into a byte array before decrypting the byte array.
Also, do not use getBytes() since the output depends on the system defaults. Use getBytes("utf-8") or whatever. That eliminates ambiguity.

Just in case anyone is interested (or feels too lazy to do their research), here is the the result code for AES-256 encryption and decryption that I put together, with help from the accepted answer and comments:
public class TokenEncryptor {
private final static String TOKEN_KEY = "fqJfdzGDvfwbedsKSUGty3VZ9taXxMVw";
public static String encrypt(String plain) {
try {
byte[] iv = new byte[16];
new SecureRandom().nextBytes(iv);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(TOKEN_KEY.getBytes("utf-8"), "AES"), new IvParameterSpec(iv));
byte[] cipherText = cipher.doFinal(plain.getBytes("utf-8"));
byte[] ivAndCipherText = getCombinedArray(iv, cipherText);
return Base64.encodeToString(ivAndCipherText, Base64.NO_WRAP);
} catch (Exception e) {
Ln.e(e);
return null;
}
}
public static String decrypt(String encoded) {
try {
byte[] ivAndCipherText = Base64.decode(encoded, Base64.NO_WRAP);
byte[] iv = Arrays.copyOfRange(ivAndCipherText, 0, 16);
byte[] cipherText = Arrays.copyOfRange(ivAndCipherText, 16, ivAndCipherText.length);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(TOKEN_KEY.getBytes("utf-8"), "AES"), new IvParameterSpec(iv));
return new String(cipher.doFinal(cipherText), "utf-8");
} catch (Exception e) {
Ln.e(e);
return null;
}
}
private static byte[] getCombinedArray(byte[] one, byte[] two) {
byte[] combined = new byte[one.length + two.length];
for (int i = 0; i < combined.length; ++i) {
combined[i] = i < one.length ? one[i] : two[i - one.length];
}
return combined;
}
}

It's an extension of Artjom B answer and working for me.
public String encryptMsg(String message, SecretKey secret)
throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidParameterSpecException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {
Cipher cipher = null;
cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secret);
byte[] cipherText = cipher.doFinal(message.getBytes("UTF-8"));
return Base64.encodeToString(cipherText, Base64.NO_WRAP);
}
public String decryptMsg(String cipherText, SecretKey secret)
throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidParameterSpecException, InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException, UnsupportedEncodingException {
Cipher cipher = null;
cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secret);
byte[] decode = Base64.decode(cipherText, Base64.NO_WRAP);
String decryptString = new String(cipher.doFinal(decode), "UTF-8");
return decryptString;
}

Kotlin version of #Oleksiy 's answer.
<script src="https://gist.github.com/kasim1011/a5a9644a60c33a4df3c29f4b34cf93a4.js"></script>
import android.util.Base64
import java.util.*
import javax.crypto.Cipher
import javax.crypto.spec.IvParameterSpec
import javax.crypto.spec.SecretKeySpec
private const val algorithm = "AES"
private const val tokenKey = "fqJfdzGDvfwbedsKSUGty3VZ9taXxMVw"
private const val padding = "AES/CBC/PKCS5Padding"
private const val ivSize = 16
fun String.encryptAES(): String {
val tokenBytes = tokenKey.toByteArray(Charsets.UTF_8)
val secretKey = SecretKeySpec(tokenBytes, algorithm)
val ivByteArray = ByteArray(ivSize)
val iv = IvParameterSpec(ivByteArray)
val cipher = Cipher.getInstance(padding)
cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv)
val cipherText = cipher.doFinal(toByteArray(Charsets.UTF_8))
val ivAndCipherText = getCombinedArray(ivByteArray, cipherText)
return Base64.encodeToString(ivAndCipherText, Base64.NO_WRAP)
}
fun String.decryptAES(): String {
val tokenBytes = tokenKey.toByteArray(Charsets.UTF_8)
val secretKey = SecretKeySpec(tokenBytes, algorithm)
val ivAndCipherText = Base64.decode(this, Base64.NO_WRAP)
val cipherText = Arrays.copyOfRange(ivAndCipherText, ivSize, ivAndCipherText.size)
val ivByteArray = Arrays.copyOfRange(ivAndCipherText, 0, ivSize)
val iv = IvParameterSpec(ivByteArray)
val cipher = Cipher.getInstance(padding)
cipher.init(Cipher.DECRYPT_MODE, secretKey, iv)
return cipher.doFinal(cipherText).toString(Charsets.UTF_8)
}
private fun getCombinedArray(one: ByteArray, two: ByteArray): ByteArray {
val combined = ByteArray(one.size + two.size)
for (i in combined.indices) {
combined[i] = if (i < one.size) one[i] else two[i - one.size]
}
return combined
}

Android javax.io.IOException: last block incomplete in decryption

I am trying to make a encryption and decryption app but in decryption method I got javax.crypto.IllegalBlockSizeException: last block incomplete in decryption
byte[] key = ("Sh").getBytes("UTF-8");
MessageDigest sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16);
secretKeySpec = new SecretKeySpec(key, "AES");
cipher = Cipher.getInstance("AES");
public void dec (String dir)
{
try{
cipher.init(Cipher.DECRYPT_MODE, secretKeySpec);
String cleartextFile = dir;
FileInputStream fis = new FileInputStream(cleartextFile);
CipherInputStream cis = new CipherInputStream(fis, cipher);
FileOutputStream fos = new FileOutputStream(dir);
block = new byte[6];
while ((i = cis.read(block)) != -1) {
fos.write(block, 0, i);
}
fos.close();
}
catch(Exception ex)
{
Toast.makeText(MainActivity.this, "Chiper Error"+ex, Toast.LENGTH_LONG).show();
}
}