Develop Reference

Convert AES encryption java to Python

I hava Java code that do AES encryption, and i would like to convert it so it work in python. This is a main class, i made initVector constants so it would be easier to see if it work:
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.*;
import java.io.BufferedWriter;
public class test {
public static void main(String [] args)
{
String ss = "pUypiz-7hJ0y_JtpKWaydp";
String url = "";
String toBeEncrypted = "";
String initVector = "IqtY8jgALtjZNLM5";
String encodedInitVector = Encryptor.encodeB64mod(initVector.getBytes());
toBeEncrypted = "ch21979714702=put";
ss = Encryptor.decodeB64Mod(ss);
url = "i=" + encodedInitVector + "\n&a=" + Encryptor.encrypt(initVector, ss, toBeEncrypted);
System.out.println(url);
}
}
And this is Encryptor class:
import android.util.Base64;
import java.util.Random;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.io.IOUtils;
import java.util.*;
public class Encryptor {
public static String encrypt(String initVector, String key, String clearText) {
try {
byte[] value = clearText.getBytes("UTF-8");
IvParameterSpec iv = new IvParameterSpec(initVector.getBytes("UTF-8"));
SecretKeySpec skeySpec = new SecretKeySpec(Base64.decode(key, 0), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher.init(1, skeySpec, iv);
return encodeB64mod(cipher.doFinal(value));
} catch (Exception ex) {
ex.printStackTrace();
return "";
}
}
public static String encodeB64mod(byte[] bytes) {
return Base64.encodeToString(bytes, 2).replace('+', '-').replace(IOUtils.DIR_SEPARATOR_UNIX, '_').replace("=", "");
}
}
I tried to make it work in python but i am doing something wrong
EDIT:
import base64
from Crypto.Cipher import AES
from Crypto import Random
raw ='ch21979714702=put'.encode('utf-8')
key = 'pUypiz-7hJ0y_JtpKWaydp' #should be conveted to hex
iv = b'IqtY8jgALtjZNLM5'
cipher = AES.new( key, AES.MODE_CBC, iv )
print (base64.b64encode( cipher.encrypt( raw ) ).decode('utf-8') )

You are requiring base64url decoding, which isn't the generic base 64 encoding: it replaces + with - and / with _. This is why the reverse replacement is performed in Java.
Here is the correct way to decode it. Please upvote it and downvote any answers that do not include the replacement characters or final padding with the = character.

The problem was in Python was that you need to use padding
from Crypto.Util import Padding
Padding.pad(raw, 16, style='pkcs7')
https://www.pycryptodome.org/en/latest/src/util/util.html
Unlike in java in Python you need to add that you want to use padding.

Generating a Symmetric DES Key in java

I wanna generate a DES key i java , This is the code:
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
public class Deskey {
public static void main(String[] argv) throws Exception {
// Generate a DES key
KeyGenerator keyGen = KeyGenerator.getInstance("DES");
SecretKey key = keyGen.generateKey();
}
}
I get the error " The value of local variable p is not used".

What is the difference between These method below? [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 5 years ago.
Improve this question
i am learning encryption in java and used these two tutorials yet This from Code2learn
and This from howtodoinjava.com
when i try to encrypt hello from these example code both gives different encrypted strings, i have tried a lot to find that what is the main difference between these examples that is causing different encrypted strings of same passwords as both are using AES ..
Code from code 2 learn
package nomad;
import java.security.*;
import java.security.spec.InvalidKeySpecException;
import javax.crypto.*;
import sun.misc.*;
public class AESencrp {
private static final String ALGO = "AES";
private static final byte[] keyValue =
new byte[] { 'T', 'h', 'e', 'B', 'e', 's', 't',
'S', 'e', 'c', 'r','e', 't', 'K', 'e', 'y' };
public static String encrypt(String Data) throws Exception {
Key key = generateKey();
Cipher c = Cipher.getInstance(ALGO);
c.init(Cipher.ENCRYPT_MODE, key);
byte[] encVal = c.doFinal(Data.getBytes());
String encryptedValue = new BASE64Encoder().encode(encVal);
return encryptedValue;
}
public static String decrypt(String encryptedData) throws Exception {
Key key = generateKey();
Cipher c = Cipher.getInstance(ALGO);
c.init(Cipher.DECRYPT_MODE, key);
byte[] decordedValue = new BASE64Decoder().decodeBuffer(encryptedData);
byte[] decValue = c.doFinal(decordedValue);
String decryptedValue = new String(decValue);
return decryptedValue;
}
private static Key generateKey() throws Exception {
Key key = new SecretKeySpec(keyValue, ALGO);
return key;
}
}
package nomad;
public class Checker {
public static void main(String[] args) throws Exception {
String password = "mypassword";
String passwordEnc = AESencrp.encrypt(password);
String passwordDec = AESencrp.decrypt(passwordEnc);
System.out.println("Plain Text : " + password);
System.out.println("Encrypted Text : " + passwordEnc);
System.out.println("Decrypted Text : " + passwordDec);
}
}
Code for how to do in java
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class AES {
private static SecretKeySpec secretKey;
private static byte[] key;
public static void setKey(String myKey)
{
MessageDigest sha = null;
try {
key = myKey.getBytes("UTF-8");
sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16);
secretKey = new SecretKeySpec(key, "AES");
}
catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
public static String encrypt(String strToEncrypt, String secret)
{
try
{
setKey(secret);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretKey);
return Base64.getEncoder().encodeToString(cipher.doFinal(strToEncrypt.getBytes("UTF-8")));
}
catch (Exception e)
{
System.out.println("Error while encrypting: " + e.toString());
}
return null;
}
public static String decrypt(String strToDecrypt, String secret)
{
try
{
setKey(secret);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5PADDING");
cipher.init(Cipher.DECRYPT_MODE, secretKey);
return new String(cipher.doFinal(Base64.getDecoder().decode(strToDecrypt)));
}
catch (Exception e)
{
System.out.println("Error while decrypting: " + e.toString());
}
return null;
}
}
public static void main(String[] args)
{
final String secretKey = "ssshhhhhhhhhhh!!!!";
String originalString = "howtodoinjava.com";
String encryptedString = AES.encrypt(originalString, secretKey) ;
String decryptedString = AES.decrypt(encryptedString, secretKey) ;
System.out.println(originalString);
System.out.println(encryptedString);
System.out.println(decryptedString);
}
I have added the codes as one of the comments says that external links are not accessible by everyone .
Keep in mind that secretkeys and passowrd are the same in my code.
Adding my own code..
name it as code 1
AES Class
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Base64;
public class AES {
public static SecretKeySpec secretKeySpec;
private static byte[] key;
public static String setKey(String myKey) throws Exception {
MessageDigest sha=null;
key =myKey.getBytes("UTF-8");
sha=MessageDigest.getInstance("SHA-1");
key=sha.digest(key);
key= Arrays.copyOf(key,16);
secretKeySpec=new SecretKeySpec(key,"AES");
return myKey;
}
public static String encrypt(String strToencrypt, String secret) throws Exception {
String s= setKey(secret);
System.out.println(s);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE,secretKeySpec);
return Base64.getEncoder().encodeToString(cipher.doFinal(strToencrypt.getBytes("UTF-8")));
}
public static String decryt(String strToDec , String secret) throws Exception {
setKey(secret);
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE,secretKeySpec);
return new String(cipher.doFinal(Base64.getDecoder().decode(strToDec)));
}
}
Main Class of above AES Class
public class Main {
public static void main(String[] args) throws Exception {
AES aes = new AES();
String ss=null;
String sd=null;
ss=aes.encrypt("hello","TheBestSecretKey");
sd=aes.decryt(ss,"TheBestSecretKey");
System.out.println("The Encrypted == " + ss);
System.out.println("The Decrypted == " + sd);
}
}
Another Code
Name It as Code 2
package sample;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Base64;
public class Main {
private static final String ALGO ="AES";
private static String string = "TheBestSecretKey";
private static byte[] key ;
private static SecretKeySpec secretKeySpec;
public static String aesEncrypt(String en) throws Exception {
Key key = new SecretKeySpec(string.getBytes(),ALGO);
Cipher c = Cipher.getInstance("AES/ECB/PKCS5Padding");
c.init(Cipher.ENCRYPT_MODE,key);
byte[] encValue =c.doFinal(en.getBytes("UTF-8"));
String encryptedValue= new BASE64Encoder().encode(encValue);
return encryptedValue;
}
public static String aesDecrypt(String De) throws Exception{
Key key = new SecretKeySpec(string.getBytes(),"AES");
Cipher c = Cipher.getInstance("AES/ECB/PKCS5Padding");
c.init(Cipher.DECRYPT_MODE,key);
// return new String(c.doFinal(Base64.getDecoder().decode(De)));
byte[]decodedVlue=new BASE64Decoder().decodeBuffer(De);
byte[] decValue = c.doFinal(decodedVlue);
String deccryptedValue = new String(decValue);
return deccryptedValue;
}
public static void main(String[] args) throws Exception {
String password = "hello";
String passEnc= Main.aesEncrypt(password);
System.out.println(passEnc);
String passDec = Main.aesDecrypt(passEnc);
System.out.println(passDec);
}
}
here are the codes
now i am also posting encrypted strings
using SecretSpecKey TheBestSecretKey and hello as the string to be encrypted
CODE 1 UlQiIs/K0EwcSKbWMjcT1g==
CODE 2 hHDBo1dJYj5RcjdFA6BBfw==

ECB and CBC AES output is equal in Java

I've played around with the Java AES En/Decryption and used different cyper modes for this. Namely I use CBC and ECB. As ECB is considered to be weak, I wanted to go with CBC.
I assumed the output of the encrypted texts ob cbc and ecb are different, but they are equal. How is this possible?
import java.io.IOException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Hex;
import com.instana.backend.common.exception.InstanaException;
public class AESTest {
private static String pwd = "etjrgp9user9fu3984h1&(/&%$§";
public static void main(String[] args) throws Exception {
System.out.println("UNSECURE WITH ECB:");
String ecbEncrypt = encrypt("YOLO", cypher(Cipher.ENCRYPT_MODE, "AES"));
System.out.println("Encrypted: " + ecbEncrypt);
String ebcDecrypt = decrypt(ecbEncrypt, cypher(Cipher.DECRYPT_MODE, "AES"));
System.out.println("Decrypted: " + ebcDecrypt);
System.out.println("=====================================");
System.out.println("SECURE WITH CBC");
String cbcEncrypt = encrypt("YOLO", cypher(Cipher.ENCRYPT_MODE, "AES/CBC/PKCS5Padding"));
System.out.println("Encrypted: " + cbcEncrypt);
String cbcDecrypt = decrypt(cbcEncrypt, cypher(Cipher.DECRYPT_MODE, "AES/CBC/PKCS5Padding"));
System.out.println("Decrypted: " + cbcDecrypt);
System.out.println("=====================================");
System.out.println("Decrypting CBC with ECB");
}
public static String encrypt(String superDuperSecret, Cipher cipher) throws IOException {
try {
byte[] encrypted = cipher.doFinal(superDuperSecret.getBytes("UTF-8"));
return new String(new Hex().encode(encrypted));
} catch (Exception e) {
throw new InstanaException("Encryption of token failed.", e);
}
}
public static String decrypt(String superDuperSecret, Cipher cipher) {
try {
byte[] encrypted1 = new Hex().decode(superDuperSecret.getBytes("UTF-8"));
return new String(cipher.doFinal(encrypted1));
} catch (Exception e) {
throw new InstanaException("Encrypted text could not be decrypted.", e);
}
}
private static Cipher cypher(int mode, String method)
throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, InvalidKeySpecException,
InvalidAlgorithmParameterException {
SecretKeyFactory skf = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
KeySpec spec = new PBEKeySpec(pwd.toCharArray(), pwd.getBytes(), 128, 128);
SecretKey tmp = skf.generateSecret(spec);
SecretKey key = new SecretKeySpec(tmp.getEncoded(), "AES");
Cipher cipher = Cipher.getInstance(method);
if(method.contains("CBC")) {
byte[] ivByte = new byte[cipher.getBlockSize()];
IvParameterSpec ivParamsSpec = new IvParameterSpec(ivByte);
cipher.init(mode, key, ivParamsSpec);
}else{
cipher.init(mode, key);
}
return cipher;
}
}

Since you're passing an empty IV (you never put anything inside your ivByte), the operations performed for the first block are identical regardless of the mode being used. Encrypting a longer payload would result in the second block being chained to the first block in the case of CBC and the following blocks would be different between ECB/CBC.
You should pass a non-empty IV when using CBC mode, so the first block will be xorred with the IV, resulting in different encrypted values starting from the first block.

Getting private key from file in java

I have private key file with "key" extension.I know that is generated by "Admin-PKI" programm.I must read it as object of PrivateKey type in java to use it for digital signature generation.I tried open it in text editor,but there are not header and footer such as "begin private key" and "end private key".How can i know what algorithm was used to generate the private key?Can i do this without knowing algorithm?

the code below loads a file key.pem, you will need the bouncycastle library (http://bouncycastle.org/)
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.security.KeyPair;
import java.security.Security;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openssl.PEMReader;
public class LoadKey {
public static void main(String [] args) throws Exception {
Security.addProvider(new BouncyCastleProvider());
KeyPair keyPair = readKeyPair(new File("key.pem"));
}
private static KeyPair readKeyPair(File privateKey) throws IOException {
FileReader fileReader = new FileReader(privateKey);
PEMReader r = new PEMReader(fileReader);
try {
return (KeyPair) r.readObject();
} catch (IOException ex) {
throw new IOException("The private key could not be decrypted", ex);
} finally {
r.close();
fileReader.close();
}
}
}
compile and run with
javac -cp bcprov-jdk16-146.jar:. LoadKey.java
java -cp bcprov-jdk16-146.jar:. -ea LoadKey