Java: How to convert String to base64string? - java

I am using this method to decrypt my incoming messages:
private static String decrypt(String key, String initVector, String dataToDecrypt) {
try {
IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec skeySpec = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);
String safeString = dataToDecrypt.replace('-', '+').replace('_', '/');
byte[] decodedString = Base64.decodeBase64(safeString);
byte[] original = cipher.doFinal(decodedString);
return new String(original);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
However, my Android app crashes, showing the following exception:
java.lang.NoSuchMethodError: No static method
decodeBase64(Ljava/lang/String;)[B in class
Lorg/apache/commons/codec/binary/Base64; or its super classes
(declaration of 'org.apache.commons.codec.binary.Base64' appears in
/system/framework/ext.jar)
accordingly, the method decodeBase64 takes base64string, but I pass string. Here comes my question:
How to convert String to base64string ?!
Please note that I am trying to DECODE not ENCODE. Almost all the solutions provided are for the encoding part which is not my worry.
P.S.: I am developing an Android-app on Android-Studio

try this:
Base64.encodeToString(mStringToEncode.getBytes(), Base64.NO_WRAP)
it exist many encoding mode use autocompletion to see more Base64.NO_WRAP, Base64.CRLF, etc...
you need to import package:
import android.util.Base64;

public static String toBase64(String value){
if (value == null)
value = "";
return Base64.encodeToString(value.trim().getBytes(), android.util.Base64.DEFAULT);
}

Have you check this answer
// decode data from base 64
private static byte[] decodeBase64(String dataToDecode)
{
byte[] dataDecoded = Base64.decode(dataToDecode, Base64.DEFAULT);
return dataDecoded;
}
//enconde data in base 64
private static byte[] encodeBase64(byte[] dataToEncode)
{
byte[] dataEncoded = Base64.encode(dataToEncode, Base64.DEFAULT);
return dataEncoded;
}

Try this code
private static String encryptNew(String key, String initVector, String dataToEncrypt) throws Exception{
byte[] plainTextbytes = dataToEncrypt.getBytes("UTF-8");
byte[] keyBytes = key.getBytes("UTF-8");
byte[] IvkeyBytes = initVector.getBytes("UTF-8");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
SecretKeySpec secretKeySpec = new SecretKeySpec(keyBytes, "AES");
IvParameterSpec ivParameterSpec = new IvParameterSpec(IvkeyBytes);
cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivParameterSpec);
plainTextbytes = cipher.doFinal(plainTextbytes);
return Base64.encodeToString(plainTextbytes, Base64.DEFAULT);
}
private static String decrypt(String key, String initVector, String dataToDecrypt) {
try {
byte[] cipheredBytes = Base64.decode(dataToDecrypt, Base64.DEFAULT);
byte[] keyBytes = key.getBytes("UTF-8");
byte[] IvkeyBytes = initVector.getBytes("UTF-8");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
SecretKeySpec secretKeySpecy = new SecretKeySpec(keyBytes, "AES");
IvParameterSpec ivParameterSpec = new IvParameterSpec(IvkeyBytes);
cipher.init(Cipher.DECRYPT_MODE, secretKeySpecy, ivParameterSpec);
cipheredBytes = cipher.doFinal(cipheredBytes);
return new String(cipheredBytes,"UTF-8");
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}

Related

Image encryption and decryption in android Java AES256

I am trying to fetch image from the camera & want to encrypt that bitmap and want to store that bitmap in internal storage in encrypted format and store path of that file in Sqlite DB also want to decrypt that file from path receiving from the Sqlite DB.
Using code following.
For Camera I Am using normal camera code
and found a bitmap mImageCaptureBitmap
for encryption and decryption we use following.
private static String Key = "key#123";
public static byte[] encryptString(String stringToEncode) throws NullPointerException {
try {
SecretKeySpec skeySpec = getKey(Key);
byte[] clearText = stringToEncode.getBytes("UTF8");
final byte[] iv = new byte[16];
Arrays.fill(iv, (byte) 0x00);
IvParameterSpec ivParameterSpec = new IvParameterSpec(iv);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivParameterSpec);
byte[] encryptedValue = cipher.doFinal(clearText);
return encryptedValue;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public static String decryptString(String stringToEncode) throws NullPointerException {
try {
SecretKeySpec skeySpec = getKey(Key);
final byte[] iv = new byte[16];
Arrays.fill(iv, (byte) 0x00);
IvParameterSpec ivParameterSpec = new IvParameterSpec(iv);
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
cipher.init(Cipher.DECRYPT_MODE, skeySpec, ivParameterSpec);
byte[] cipherData = cipher.doFinal(Base64.decode(stringToEncode.getBytes("UTF-8"),
Base64.DEFAULT));
String decoded = new String(cipherData, "UTF-8");
return decoded;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static SecretKeySpec getKey(String password) throws UnsupportedEncodingException {
int keyLength = 256;
byte[] keyBytes = new byte[keyLength / 8];
Arrays.fill(keyBytes, (byte) 0x0);
byte[] passwordBytes = password.getBytes("UTF-8");
int length = passwordBytes.length < keyBytes.length ? passwordBytes.length : keyBytes.length;
System.arraycopy(passwordBytes, 0, keyBytes, 0, length);
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
return key;
}
for storing file in local
public static void storeFile(Bitmap bitmap, String filename, Context ctx
,String ID,String type){
ContextWrapper cw = new ContextWrapper(ctx);
File directory = cw.getDir("IntegratorApp", Context.MODE_PRIVATE);
File file = new File(directory, filename);
DatabaseHelper mdaDatabaseHelper = new DatabaseHelper(ctx);
mdaDatabaseHelper.insertDocData(leadID,file.getAbsolutePath(),docType);
try {
StorageUnit.saveImage(ctx,bitmap,filename);
} catch (IOException e) {
e.printStackTrace();
}
}
I don't know where I am doing wrong but the image is not stored in db in encrypted format.
Thanks in advance

Use Java Cipher equivalent in Flutter

a i need help to decrypt values generated in Android Java App on Flutter.
I need a class who this but in Dart/Flutter:
public class TrippleDes {
// public static String ALGO = "DESede/CBC/PKCS7Padding";
public static String ALGO = "DESede/ECB/PKCS7Padding";
public static String _encrypt(String message, String secretKey) throws Exception {
Cipher cipher = Cipher.getInstance(ALGO);
cipher.init(Cipher.ENCRYPT_MODE, getSecreteKey(secretKey));
byte[] plainTextBytes = message.getBytes("UTF-8");
byte[] buf = cipher.doFinal(plainTextBytes);
byte[] base64Bytes = Base64.encode(buf, Base64.DEFAULT);
String base64EncryptedString = new String(base64Bytes);
return base64EncryptedString;
}
public static String _decrypt(String encryptedText, String secretKey) throws Exception {
byte[] message = Base64.decode(encryptedText.getBytes(), Base64.DEFAULT);
Cipher decipher = Cipher.getInstance(ALGO);
decipher.init(Cipher.DECRYPT_MODE, getSecreteKey(secretKey));
byte[] plainText = decipher.doFinal(message);
return new String(plainText, "UTF-8");
}
public static SecretKey getSecreteKey(String secretKey) throws Exception {
MessageDigest md = MessageDigest.getInstance("SHA-1");
byte[] digestOfPassword = md.digest(secretKey.getBytes("utf-8"));
byte[] keyBytes = Arrays.copyOf(digestOfPassword, 24);
SecretKey key = new SecretKeySpec(keyBytes, "DESede");
return key;
}
}

Decrypting returns, javax.crypto.BadPaddingException: Given final block not properly padded

Im trying to decrypt the encrypted xml file. Im getting it as a inputstream as follows.I have the correct encrypt key. but each time my program returns empty string. Every time i enter the correct key. but each time it returns Badpadding Exception.
try{
InputStream is = new ByteArrayInputStream(decryption.getFileData().getBytes());
String xmlEncryptedStr = getStringFromInputStream(is);
String xmlStr = CipherUtils.decrypt(xmlEncryptedStr, new Long(key));
.......
here is my CipherUtils.java class
.........
public static String decrypt(String strToDecrypt,Long key)
{
String keyString=String.format("%016d", key);
//System.out.println("decrypt keyString :"+keyString);
return decrypt(strToDecrypt, keyString.getBytes());
}
public static String decrypt(String strToDecrypt,byte[] key)
{
if(strToDecrypt==null)
return strToDecrypt;
try
{
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
final SecretKeySpec secretKey = new SecretKeySpec(key, "AES");
cipher.init(Cipher.DECRYPT_MODE, secretKey);
final String decryptedString = new String(cipher.doFinal(Base64.decodeBase64(strToDecrypt)));
System.out.println("CipherUtils.decryptedString :"+decryptedString);
return decryptedString;
}
catch (Exception e)
{
log.error("Ops!", e);
}
return null;
}
.......
For more information here is my encrypting code
public static String encrypt(String strToEncrypt,Long key)
{
String keyString=String.format("%016d", key);
//System.out.println("encrypt keyString :"+keyString);
return encrypt(strToEncrypt,keyString.getBytes());
}
public static String encrypt(String strToEncrypt,byte[] key)
{
if(strToEncrypt==null)
return strToEncrypt;
try
{
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
final SecretKeySpec secretKey = new SecretKeySpec(key, "AES");
cipher.init(Cipher.ENCRYPT_MODE, secretKey);
final String encryptedString = Base64.encodeBase64String(cipher.doFinal(strToEncrypt.getBytes()));
// System.out.println("CipherUtils.encrypt :"+encryptedString);
return encryptedString;
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
I am sorry I couldn't comment so I am writing in answers section.
I faced this issue when I was using different keys though I was passing the same but i used CBC methodology.
Just to note that have you checked that encryption is also done by the AES/ECB/PKCS5Padding and not other format like AES/CBC/PKCS5Padding
Also check if key format for encryption is also having the same format like %016d of your keyValue. Also the key is 16 char long.
I created a simple AES and DESede encryption utility and it worked fine.
private static final byte[] keyValue = new String(
"CjxI&S#V&#DSA_S0dA-SDSA$").getBytes();
public static void main(String[] args) throws Exception {
Client cli = new Client();
System.out.println(cli.encrypt("your password for encryption"));
Client cli1 = new Client();
System.out.println(cli1.decrypt("fTsgVQtXvv49GynHazT4OGZ4Va1H57d+6AM+44Ex040="));
}
public String encrypt(String Data) throws Exception {
Key key = new SecretKeySpec(keyValue, "AES");
Cipher c = Cipher.getInstance("AES/ECB/PKCS5Padding");
c.init(Cipher.ENCRYPT_MODE, key);
byte[] encVal = c.doFinal(Data.getBytes());
String encryptedValue = DatatypeConverter.printBase64Binary(encVal);
// String encryptedValue = new BASE64Encoder().encode(encVal);
return encryptedValue;
}
public String decrypt(String encryptedData) throws Exception {
Key key = new SecretKeySpec(keyValue, "AES");
Cipher c = Cipher.getInstance("AES/ECB/PKCS5Padding");
c.init(Cipher.DECRYPT_MODE, key);
byte[] decordedValue = DatatypeConverter
.parseBase64Binary(encryptedData);
byte[] decValue = c.doFinal(decordedValue);
String decryptedValue = new String(decValue);
return decryptedValue;
}

Android/Java Decryption Block Size Calculation - Cipher functions:EVP_DecryptFinal_ex:WRONG_FINAL_BLOCK_LENGTH

I am getting an error "Cipher functions:EVP_DecryptFinal_ex:WRONG_FINAL_BLOCK_LENGTH" and I am not sure why. Can someone please tell me how to fix this?
Here is how I call it
String encrypted = "E5ADDEB05D9D7B3925B7DE16B560D87C";
String sKey = "3985661DD71D591665BD39476636486B";
This is the procedure
public static String decrypt2(final String sEncryptedMessageBase64,
final String sSymKeyHex,
final String sIvHex)
{
final byte[] byteEncryptedMessage = Base64.decode(sEncryptedMessageBase64, Base64.DEFAULT);
try
{
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
final SecretKeySpec symKey = new SecretKeySpec(byteSymKeyData, "AES");
final IvParameterSpec iv = new IvParameterSpec(byteIvData);
cipher.init(Cipher.DECRYPT_MODE, symKey, iv);
final byte[] encodedMessage = cipher.doFinal(byteEncryptedMessage);
final String message = new String(encodedMessage, Charset.forName("UTF-8"));
return message;
}
catch (GeneralSecurityException e) {
Log.e("%%%%%", e.getMessage());
throw new IllegalStateException(
"Unexpected exception during decryption", e);
}
}
This is the error I am getting
error:1e06b07b:Cipher functions:EVP_DecryptFinal_ex:WRONG_FINAL_BLOCK_LENGTH
Thanks for any help you can provide

How to encrypt a stringbuilder message using AES algorithm in java

I have a stringBuilder message appended with "||" symbol.(Ex: Hi||How||are||26 04 2016||finish) i have to encrypt the message and send it to the server using AES and decrypt the same at the server side. Can anyone help me out in solving this?
You can encrypt and decrypt like this:
public class AES {
public static byte[] encrypt(String key, String initVector, String value) {
try {
IvParameterSpec vector = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec secretKey = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.ENCRYPT_MODE, secretKey, vector);
byte[] encrypted = cipher.doFinal(value.getBytes());
System.out.println("encrypted string: "+ Base64.encodeBase64(encrypted));
return Base64.encodeBase64(encrypted);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static String decrypt(String key, String initVector, byte[] encrypted) {
try {
IvParameterSpec vector = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec secretKey = new SecretKeySpec(key.getBytes("UTF-8"), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(Cipher.DECRYPT_MODE, secretKey, vector);
byte[] original = cipher.doFinal(Base64.decodeBase64(encrypted));
return new String(original);
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}
public static void main(String[] args) {
String key = "Foo12345Bar67890"; // 128 bit key
String initVector = "RandomInitVector"; // 16 bytes IV
StringBuilder sb = new StringBuilder("Hi||How||are||26 04 2016||finish"); //Your Text here
byte[] encryptedBytes = encrypt(key, initVector, sb.toString());
System.out.println(decrypt(key, initVector,encryptedBytes));
}
}

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