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Forked from scotttam/Decrypter.java
Created July 20, 2018 22:46
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encrypt and decrypt with PBKDF2/SHA1 and AES
import javax.crypto.Cipher;
import java.security.spec.KeySpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.SecretKeyFactory;
import java.security.AlgorithmParameters;
import javax.crypto.spec.IvParameterSpec;
public class Decrypter {
Cipher dcipher;
byte[] salt = new String("12345678").getBytes();
int iterationCount = 1024;
int keyStrength = 256;
SecretKey key;
byte[] iv;
Decrypter(String passPhrase) throws Exception {
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
KeySpec spec = new PBEKeySpec(passPhrase.toCharArray(), salt, iterationCount, keyStrength);
SecretKey tmp = factory.generateSecret(spec);
key = new SecretKeySpec(tmp.getEncoded(), "AES");
dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
}
public String encrypt(String data) throws Exception {
dcipher.init(Cipher.ENCRYPT_MODE, key);
AlgorithmParameters params = dcipher.getParameters();
iv = params.getParameterSpec(IvParameterSpec.class).getIV();
byte[] utf8EncryptedData = dcipher.doFinal(data.getBytes());
String base64EncryptedData = new sun.misc.BASE64Encoder().encodeBuffer(utf8EncryptedData);
System.out.println("IV " + new sun.misc.BASE64Encoder().encodeBuffer(iv));
System.out.println("Encrypted Data " + base64EncryptedData);
return base64EncryptedData;
}
public String decrypt(String base64EncryptedData) throws Exception {
dcipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
byte[] decryptedData = new sun.misc.BASE64Decoder().decodeBuffer(base64EncryptedData);
byte[] utf8 = dcipher.doFinal(decryptedData);
return new String(utf8, "UTF8");
}
public static void main(String args[]) throws Exception {
Decrypter decrypter = new Decrypter("ABCDEFGHIJKL");
String encrypted = decrypter.encrypt("the quick brown fox jumps over the lazy dog");
String decrypted = decrypter.decrypt(encrypted);
System.out.println(decrypted);
}
}
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