I need to hide certain raw values from end user output (mostly primary keys, could be ~100 of them per request) simply so that the database can't easily be probed or iterated through. Speed of the encryption is of higher importance than the actual impenetrability of the values.
I am currently using PBEWithMD5AndDES in the following wrapper - is this overkill? I am new to using Java as a web backend.
public class SecurityHelper {
private static final String DEFAULT_KEY = "some-key-here";
private SecretKey secretKey;
private PBEParameterSpec parameterSpec;
private Cipher cipher;
public SecurityHelper() {
try {
char[] moduleKeyChars = DEFAULT_KEY.toCharArray();
KeySpec keySpec = new PBEKeySpec(moduleKeyChars);
secretKey = SecretKeyFactory.getInstance(
"PBEWithMD5AndDES").generateSecret(keySpec);
parameterSpec = new PBEParameterSpec(new byte[8], 1);
cipher = Cipher.getInstance("PBEWithMD5AndDES");
} catch (Exception e) {
e.printStackTrace();
}
}
public String encrypt(String secret) {
String encrypted = null;
try {
cipher.init(Cipher.ENCRYPT_MODE, secretKey, parameterSpec);
byte[] stateBytes = cipher.doFinal(secret.getBytes("UTF-8"));
encrypted = DatatypeConverter.printBase64Binary(stateBytes);
} catch (Exception e) {
e.printStackTrace();
}
return encrypted;
}
public String decrypt(String encrypted) {
String decrypted = null;
try {
cipher.init(Cipher.DECRYPT_MODE, secretKey, parameterSpec);
byte[] stringBinary = DatatypeConverter.parseBase64Binary(encrypted);
decrypted = new String(cipher.doFinal(stringBinary));
} catch (Exception e) {
e.printStackTrace();
}
return decrypted;
}
}
Or am I dramatically better off using something like XOR cipher?
If you do want to hide the values from a user, I don't see why you should be either encrypting or hashing them. What you should be doing is to generate random and unique keys. Have you thought of using GUIDs instead ?
If you think GUIDs are too long, you could generate a random string of a predefined length. Make your database column a unique index for the benefit of faster searching.
This is how URL shortners such as bit.ly or goo.gl works. This would prevent anyone from crawling through your database using primary keys.
Yes, encryption is probably overkill. You should however not fall into a trap and use less secure cryptographic primitives because of it. Especially using CBC mode security, a static salt etc. are really mistakes you should avoid. XOR or DES encryption is really not worth the name, these encryption schemes can be broken in minutes.
If encryption is overkill with regards to server performance is a question only you can answer. Usually IO and complex SQL queries will task your system more than simple symmetric encryption of a few bytes of data.
I'll show you your class retrofitted with GCM and - in case that's not available or if the tag size of 12 bytes is too much overhead - CTR mode encryption.
You should probably only do this if it is not possible to use (random) GUID's instead.
WARNING: I would not consider the following classes to have enough input parameter checking (integer overflows etc.). I get bored when trying to implement all those checks and JUnit tests (without getting payed for it anyway :P ). Sanitize your input before calling any of the functions.
AES/GCM:
import static java.nio.charset.StandardCharsets.*;
import java.security.GeneralSecurityException;
import java.security.SecureRandom;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
public class SecurityHelperGCM {
private static final int NONCE_SIZE = 8;
private static final int TAG_SIZE = 12;
// make sure that the hexadecimals represent a *truly random* byte array
// (e.g. use SecureRandom)
private final SecretKey STATIC_SECRET_KEY = new SecretKeySpec(
hexDecode("66e517bb5fd7df840060aed7e8b58986"), "AES");
private Cipher cipher;
private static byte[] hexDecode(final String hex) {
final byte[] data = new byte[hex.length() / 2];
for (int i = 0; i < data.length; i++) {
data[i] = (byte) Integer.parseInt(hex.substring(i * 2, i * 2 + 2),
16);
}
return data;
}
public SecurityHelperGCM() {
try {
this.cipher = Cipher.getInstance("AES/GCM/NoPadding");
} catch (final Exception e) {
e.printStackTrace();
}
}
private static int generateRandomNonce(final byte[] nonceBuffer,
final int offset, final int size) {
final SecureRandom rng = new SecureRandom();
final byte[] nonce = new byte[size];
rng.nextBytes(nonce);
System.arraycopy(nonce, 0, nonceBuffer, offset, size);
clearArray(nonce);
return offset + size;
}
private static void clearArray(final byte[] nonce) {
// clean up...
for (int i = 0; i < nonce.length; i++) {
nonce[i] = 0;
}
}
private static GCMParameterSpec generateGCMParametersFromNonce(
final byte[] nonceBuffer, final int offset, final int size,
final int blockSize) {
final GCMParameterSpec gcmParameters = new GCMParameterSpec(TAG_SIZE
* Byte.SIZE, nonceBuffer, offset, size);
return gcmParameters;
}
public String encrypt(final String secret) {
final byte[] plaintext = secret.getBytes(UTF_8);
final byte[] nonceAndCiphertext = new byte[NONCE_SIZE
+ plaintext.length + TAG_SIZE];
int offset = generateRandomNonce(nonceAndCiphertext, 0, NONCE_SIZE);
final GCMParameterSpec nonceIV = generateGCMParametersFromNonce(
nonceAndCiphertext, 0, NONCE_SIZE, this.cipher.getBlockSize());
try {
this.cipher.init(Cipher.ENCRYPT_MODE, this.STATIC_SECRET_KEY,
nonceIV);
offset += this.cipher.doFinal(plaintext, 0, plaintext.length,
nonceAndCiphertext, offset);
if (offset != nonceAndCiphertext.length) {
throw new IllegalStateException(
"Something wrong during encryption");
}
// Java 8 contains java.util.Base64
return DatatypeConverter.printBase64Binary(nonceAndCiphertext);
} catch (final GeneralSecurityException e) {
throw new IllegalStateException(
"Missing basic functionality from Java runtime", e);
}
}
public String decrypt(final String encrypted) throws BadPaddingException {
final byte[] nonceAndCiphertext = DatatypeConverter
.parseBase64Binary(encrypted);
final GCMParameterSpec nonceIV = generateGCMParametersFromNonce(
nonceAndCiphertext, 0, NONCE_SIZE, this.cipher.getBlockSize());
try {
this.cipher.init(Cipher.DECRYPT_MODE, this.STATIC_SECRET_KEY,
nonceIV);
final byte[] plaintext = this.cipher.doFinal(nonceAndCiphertext,
NONCE_SIZE, nonceAndCiphertext.length - NONCE_SIZE);
return new String(plaintext, UTF_8);
} catch (final BadPaddingException e) {
throw e;
} catch (final GeneralSecurityException e) {
throw new IllegalStateException(
"Missing basic functionality from Java runtime", e);
}
}
public static void main(final String[] args) {
final String secret = "owlstead";
final SecurityHelperGCM securityHelperGCM = new SecurityHelperGCM();
final String ct = securityHelperGCM.encrypt(secret);
String pt = null;
try {
pt = securityHelperGCM.decrypt(ct);
} catch (BadPaddingException e) {
System.out.println("Ciphertext tampered, take action!");
}
System.out.println(pt);
}
}
AES/CTR:
import static java.nio.charset.StandardCharsets.*;
import java.security.GeneralSecurityException;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
public class SecurityHelperCTR {
private static final int NONCE_SIZE = 8;
// make sure that the hexadecimals represent a *truly random* byte array
// (e.g. use SecureRandom)
private final SecretKey STATIC_SECRET_KEY = new SecretKeySpec(
hexDecode("66e517bb5fd7df840060aed7e8b58986"), "AES");
private Cipher cipher;
private static byte[] hexDecode(final String hex) {
final byte[] data = new byte[hex.length() / 2];
for (int i = 0; i < data.length; i++) {
data[i] = (byte) Integer.parseInt(hex.substring(i * 2, i * 2 + 2),
16);
}
return data;
}
public SecurityHelperCTR() {
try {
this.cipher = Cipher.getInstance("AES/CTR/NoPadding");
} catch (final Exception e) {
e.printStackTrace();
}
}
private static int generateRandomNonce(final byte[] nonceBuffer,
final int offset, final int size) {
final SecureRandom rng = new SecureRandom();
final byte[] nonce = new byte[size];
rng.nextBytes(nonce);
System.arraycopy(nonce, 0, nonceBuffer, offset, size);
return offset + size;
}
private static IvParameterSpec generateIVFromNonce(
final byte[] nonceBuffer, final int offset, final int size,
final int blockSize) {
final byte[] ivData = new byte[blockSize];
System.arraycopy(nonceBuffer, offset, ivData, 0, size);
final IvParameterSpec iv = new IvParameterSpec(ivData);
return iv;
}
public String encrypt(final String secret) {
final byte[] plaintext = secret.getBytes(UTF_8);
final byte[] nonceAndCiphertext = new byte[NONCE_SIZE
+ plaintext.length];
int offset = generateRandomNonce(nonceAndCiphertext, 0, NONCE_SIZE);
final IvParameterSpec nonceIV = generateIVFromNonce(nonceAndCiphertext,
0, NONCE_SIZE, this.cipher.getBlockSize());
try {
this.cipher.init(Cipher.ENCRYPT_MODE, this.STATIC_SECRET_KEY,
nonceIV);
offset += this.cipher.doFinal(plaintext, 0, plaintext.length,
nonceAndCiphertext, offset);
if (offset != nonceAndCiphertext.length) {
throw new IllegalStateException(
"Something wrong during encryption");
}
// Java 8 contains java.util.Base64
return DatatypeConverter.printBase64Binary(nonceAndCiphertext);
} catch (final GeneralSecurityException e) {
throw new IllegalStateException(
"Missing basic functionality from Java runtime", e);
}
}
public String decrypt(final String encrypted) {
final byte[] nonceAndCiphertext = DatatypeConverter
.parseBase64Binary(encrypted);
final IvParameterSpec nonceIV = generateIVFromNonce(nonceAndCiphertext,
0, NONCE_SIZE, this.cipher.getBlockSize());
try {
this.cipher.init(Cipher.DECRYPT_MODE, this.STATIC_SECRET_KEY,
nonceIV);
final byte[] plaintext = this.cipher.doFinal(nonceAndCiphertext,
NONCE_SIZE, nonceAndCiphertext.length - NONCE_SIZE);
// note: this may return an invalid result if the value is tampered
// with
// it may even contain more or less characters
return new String(plaintext, UTF_8);
} catch (final GeneralSecurityException e) {
throw new IllegalStateException(
"Missing basic functionality from Java runtime", e);
}
}
public static void main(final String[] args) {
final String secret = "owlstead";
final SecurityHelperCTR securityHelper = new SecurityHelperCTR();
final String ct = securityHelper.encrypt(secret);
final String pt = securityHelper.decrypt(ct);
System.out.println(pt);
}
}
Related
So usually i use one java file to encrypt and decrypt a string to hex with AES,
then my angular app want to consume api, that use the result of it.
this is my old java code
package decryptoor;
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.util.Formatter;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class CryptoAndroidKoplak {
private static final String TEXT_ENCODING = "UTF-8";
private static final String CIPHER_TRANSFORMATION = "AES/CBC/PKCS5Padding";
private static final String ENCRYPTION_ALGORITM = "AES";
private static final String TAG = "Crypto";
private Cipher cipher;
private IvParameterSpec initialVector;
// private static void DEBUG(String msg){
// if(IDefines.DEBUG_LOG_TRACE){
// Log.i(TAG, msg);
// }
// }
public CryptoAndroidKoplak() {
try {
cipher = Cipher.getInstance(CIPHER_TRANSFORMATION);
initialVector = new IvParameterSpec(new byte[16]);
} catch (Exception e) {
System.out.println(e.toString());
}
}
public String encryptString(String plainText, String key) throws Exception {
return toHexString(encrypt(plainText, key)).toUpperCase();
}
public byte[] encrypt(String plainText, String key) throws Exception {
byte[] byteKey = getKeyBytes(key);
byte[] plainData = plainText.getBytes(TEXT_ENCODING);
SecretKeySpec keySpec = new SecretKeySpec(byteKey, ENCRYPTION_ALGORITM);
cipher.init(Cipher.ENCRYPT_MODE, keySpec, initialVector);
return cipher.doFinal(plainData);
}
public String decryptString(String encryptedText, String key) throws Exception {
return new String(decrypt(encryptedText, key));
}
public byte[] decrypt(String encryptedText, String key) throws Exception {
byte[] byteKey = getKeyBytes(key);
byte[] encryptData = hexToAscii(encryptedText);
SecretKeySpec keySpec = new SecretKeySpec(byteKey, ENCRYPTION_ALGORITM);
cipher.init(Cipher.DECRYPT_MODE, keySpec, initialVector);
return cipher.doFinal(encryptData);
}
public static String toMD5(String text) throws Exception {
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] data = text.getBytes(TEXT_ENCODING);
return toHexString(md.digest(data));
}
public static String toSHA1(String text) throws Exception {
MessageDigest md = MessageDigest.getInstance("SHA-1");
byte[] data = text.getBytes(TEXT_ENCODING);
return toHexString(md.digest(data));
}
private static String toHexString(byte[] bytes) {
StringBuilder sb = new StringBuilder(bytes.length * 2);
Formatter formatter = new Formatter(sb);
for (byte b : bytes) {
formatter.format("%02x", b);
}
return sb.toString();
}
private static byte[] hexToAscii(String hexStr) {
byte[] buff = new byte[hexStr.length() / 2];
int offset = 0;
for (int i = 0; i < hexStr.length(); i += 2) {
String str = hexStr.substring(i, i + 2);
buff[offset++] = (byte) Integer.parseInt(str, 16);
}
return buff;
}
private static byte[] getKeyBytes(String key) throws UnsupportedEncodingException {
byte[] keyBytes = new byte[16];
byte[] parameterKeyBytes = key.getBytes("UTF-8");
System.arraycopy(parameterKeyBytes, 0, keyBytes, 0, Math.min(parameterKeyBytes.length, keyBytes.length));
return keyBytes;
}
}
and this is my code in angular
import { Injectable } from '#angular/core';
import * as CryptoJS from 'crypto-js';
#Injectable({
providedIn: 'root'
})
export class Encryption {
constructor() {}
encryptAesToString(stringToEncrypt: string, key: string): string {
// first way
// let encrypted;
// try {
// encrypted = CryptoJS.AES.encrypt(JSON.stringify(stringToEncrypt), key);
// } catch (e) {
// console.log(e);
// }
// encrypted = CryptoJS.enc.Hex.stringify(encrypted.ciphertext);
// return encrypted;
// second way
// var b64 = CryptoJS.AES.encrypt(stringToEncrypt, key).toString();
// var e64 = CryptoJS.enc.Base64.parse(b64);
// var eHex = e64.toString(CryptoJS.enc.Hex);
// return eHex;
// third way
const key2 = CryptoJS.enc.Utf8.parse(key);
const iv = CryptoJS.enc.Utf8.parse(key);
const encrypted = CryptoJS.AES.encrypt(stringToEncrypt, key2, {
keySize: 16,
iv: iv,
mode: CryptoJS.mode.ECB,
padding: CryptoJS.pad.Pkcs7,
});
let eHex = CryptoJS.enc.Hex.stringify(encrypted.ciphertext);
return encrypted;
}
decryptAesformString(stringToDecrypt: string, key: string): string {
let decrypted: string = '';
try {
const bytes = CryptoJS.AES.decrypt(stringToDecrypt, key);
if (bytes.toString()) {
decrypted = JSON.parse(bytes.toString(CryptoJS.enc.Utf8));
}
} catch (e) {
console.log(e);
}
return decrypted;
}
}
i have try three code, the first one doesn't return hex, so i try 2 more ways but it doesn't show same encrypted string with the old java code so i cant consume the api.
any idea why this happen?
if you have better way to encrypt and decrypt with key that more simple both in angular and java, it will really help.
many thanks
after give up on how to make it same with my old java code, finally i try to make a new one hehe...
so after i read this answer, then i understand CryptoJS (library that i use in angular) implements the same key derivation function as OpenSSL. so i choose to use basic CryptoJS function to encrypt my string like this
var text = "The quick brown fox jumps over the lazy dog. 👻 👻";
var secret = "René Über";
var encrypted = CryptoJS.AES.encrypt(text, secret);
encrypted = encrypted.toString();
console.log("Cipher text: " + encrypted);
after that, what i need to do is make new java file to encrypt and decrypt aes OpenSsl, and i get what i need here in this answer. i use robert answer, cause accepted answer not really give me what i need.
but like the first answer mentioned, to encrypt and decrypt in this way, we have to install the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy. Otherwise, AES with key size of 256 won't work and throw an exception:(you won't need JCE with up-to-date java version)
so i add some functionality to force using AES with key size of 256 without to install JCE here. note to use this, actually isnt recomended, please read the comment in ericson answer
then this is my final code to encrypt and decrypt like OpenSsl
package decryptoor;
import groovy.transform.CompileStatic;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.net.URLEncoder;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.MessageDigest;
import java.security.SecureRandom;
import static java.nio.charset.StandardCharsets.*;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.Permission;
import java.security.PermissionCollection;
import java.util.Arrays;
import java.util.Base64;
import java.util.Map;
import javax.crypto.BadPaddingException;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
/**
* Mimics the OpenSSL AES Cipher options for encrypting and decrypting messages using a shared key (aka password) with symetric ciphers.
*/
#CompileStatic
class OpenSslAes {
/** OpenSSL's magic initial bytes. */
private static final String SALTED_STR = "Salted__";
private static final byte[] SALTED_MAGIC = SALTED_STR.getBytes(US_ASCII);
static String encryptAndURLEncode(String password, String clearText) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, InvalidAlgorithmParameterException, BadPaddingException, UnsupportedEncodingException {
String encrypted = encrypt(password, clearText);
return URLEncoder.encode(encrypted, UTF_8.name() );
}
/**
*
* #param password The password / key to encrypt with.
* #param data The data to encrypt
* #return A base64 encoded string containing the encrypted data.
*/
static String encrypt(String password, String clearText) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, InvalidAlgorithmParameterException, BadPaddingException {
removeCryptographyRestrictions();
final byte[] pass = password.getBytes(US_ASCII);
final byte[] salt = (new SecureRandom()).generateSeed(8);
final byte[] inBytes = clearText.getBytes(UTF_8);
final byte[] passAndSalt = array_concat(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
final byte[] hashData = array_concat(hash, passAndSalt);
final MessageDigest md = MessageDigest.getInstance("MD5");
hash = md.digest(hashData);
keyAndIv = array_concat(keyAndIv, hash);
}
final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(iv));
byte[] data = cipher.doFinal(inBytes);
data = array_concat(array_concat(SALTED_MAGIC, salt), data);
return Base64.getEncoder().encodeToString( data );
}
/**
* #see http://stackoverflow.com/questions/32508961/java-equivalent-of-an-openssl-aes-cbc-encryption for what looks like a useful answer. The not-yet-commons-ssl also has an implementation
* #param password
* #param source The encrypted data
* #return
*/
static String decrypt(String password, String source) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {
removeCryptographyRestrictions();
final byte[] pass = password.getBytes(US_ASCII);
final byte[] inBytes = Base64.getDecoder().decode(source);
final byte[] shouldBeMagic = Arrays.copyOfRange(inBytes, 0, SALTED_MAGIC.length);
if (!Arrays.equals(shouldBeMagic, SALTED_MAGIC)) {
throw new IllegalArgumentException("Initial bytes from input do not match OpenSSL SALTED_MAGIC salt value.");
}
final byte[] salt = Arrays.copyOfRange(inBytes, SALTED_MAGIC.length, SALTED_MAGIC.length + 8);
final byte[] passAndSalt = array_concat(pass, salt);
byte[] hash = new byte[0];
byte[] keyAndIv = new byte[0];
for (int i = 0; i < 3 && keyAndIv.length < 48; i++) {
final byte[] hashData = array_concat(hash, passAndSalt);
final MessageDigest md = MessageDigest.getInstance("MD5");
hash = md.digest(hashData);
keyAndIv = array_concat(keyAndIv, hash);
}
final byte[] keyValue = Arrays.copyOfRange(keyAndIv, 0, 32);
final SecretKeySpec key = new SecretKeySpec(keyValue, "AES");
final byte[] iv = Arrays.copyOfRange(keyAndIv, 32, 48);
final Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
final byte[] clear = cipher.doFinal(inBytes, 16, inBytes.length - 16);
return new String(clear, UTF_8);
}
private static byte[] array_concat(final byte[] a, final byte[] b) {
final byte[] c = new byte[a.length + b.length];
System.arraycopy(a, 0, c, 0, a.length);
System.arraycopy(b, 0, c, a.length, b.length);
return c;
}
private static void removeCryptographyRestrictions() {
if (!isRestrictedCryptography()) {
return;
}
try {
/*
* Do the following, but with reflection to bypass access checks:
*
* JceSecurity.isRestricted = false; JceSecurity.defaultPolicy.perms.clear();
* JceSecurity.defaultPolicy.add(CryptoAllPermission.INSTANCE);
*/
final Class<?> jceSecurity = Class.forName("javax.crypto.JceSecurity");
final Class<?> cryptoPermissions = Class.forName("javax.crypto.CryptoPermissions");
final Class<?> cryptoAllPermission = Class.forName("javax.crypto.CryptoAllPermission");
Field isRestrictedField = jceSecurity.getDeclaredField("isRestricted");
isRestrictedField.setAccessible(true);
setFinalStatic(isRestrictedField, true);
isRestrictedField.set(null, false);
final Field defaultPolicyField = jceSecurity.getDeclaredField("defaultPolicy");
defaultPolicyField.setAccessible(true);
final PermissionCollection defaultPolicy = (PermissionCollection) defaultPolicyField.get(null);
final Field perms = cryptoPermissions.getDeclaredField("perms");
perms.setAccessible(true);
((Map<?, ?>) perms.get(defaultPolicy)).clear();
final Field instance = cryptoAllPermission.getDeclaredField("INSTANCE");
instance.setAccessible(true);
defaultPolicy.add((Permission) instance.get(null));
}
catch (final Exception e) {
e.printStackTrace();
}
}
static void setFinalStatic(Field field, Object newValue) throws Exception {
field.setAccessible(true);
Field modifiersField = Field.class.getDeclaredField("modifiers");
modifiersField.setAccessible(true);
modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);
field.set(null, newValue);
}
private static boolean isRestrictedCryptography() {
// This simply matches the Oracle JRE, but not OpenJDK.
return "Java(TM) SE Runtime Environment".equals(System.getProperty("java.runtime.name"));
}
}
I'm writing an app which got a lot of security constraints:
It needs to store files securely encrypted, and must be able to decrypt them. Also, an Operator needs to be able to decrypt the file without the app.
To archive this, I generated a KeyPair on my PC, put the public part in my app, generate an AES SecretKey Key inside the app, encrypt and save it with my public key (for operator purposes), and put the unencrypted key in AndroidKeyStore.
To Encrypt a message, I receive the SecretKey from KeyStore, encrypt my message, get the IV I used as well as the encryptedSecretKey, and write them in a defined order to a byte array (iv->encryptedSecretKey->encryptedMessage).
To Decrypt I try the same in reverse: get the byte array, read the iv and encryptedSecretKey, and pass the rest (encryptedMessage) to my cypher to decrypt.
The problem is, that cipher.doFinal(encryptedMessage) is throwing an
javax.crypto.AEADBadTagExceptionwhich is caused by android.security.KeyStoreException: Signature/MAC verification failed.
I already checked that the encrypted message and the one I want to decrypt are exactly the same. I'm having no idea what I am doing wrong.
The class I use is the following:
package my.company.domain;
import android.content.Context;
import android.content.SharedPreferences;
import android.security.keystore.KeyProperties;
import android.security.keystore.KeyProtection;
import android.support.annotation.NonNull;
import android.util.Base64;
import android.util.Log;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.GeneralSecurityException;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class CryptoHelper {
public static final String TAG = CryptoHelper.class.getSimpleName();
private static final String KEY_ALIAS = "OI1lTI1lLI1l0";
private static final char[] KEY_PASSWORD = "Il0VELI1lO".toCharArray();
private static final String PREF_NAME = "CryptoPrefs";
private static final String KEY_ENCRYPTED_SECRET = "encryptedSecret";
private static final String ANDROID_KEY_STORE = "AndroidKeyStore";
private static final int IV_SIZE = 12;
private static final int IV_BIT_LEN = IV_SIZE * 8;
//generate 128 bit key (16), other possible values 192(24), 256(32)
private static final int AES_KEY_SIZE = 16;
private static final String AES = KeyProperties.KEY_ALGORITHM_AES;
private static final String AES_MODE = AES + "/" + KeyProperties.BLOCK_MODE_GCM + "/" + KeyProperties.ENCRYPTION_PADDING_NONE;
private static final String RSA = KeyProperties.KEY_ALGORITHM_RSA;
private static final String RSA_MODE = KeyProperties.KEY_ALGORITHM_RSA + "/" + KeyProperties.BLOCK_MODE_ECB + "/" + KeyProperties.ENCRYPTION_PADDING_NONE;
private static final String RSA_PROVIDER = "AndroidOpenSSL";
private final Context mContext;
private final SharedPreferences mPrefs;
private SecureRandom mSecureRandom;
private KeyStore mAndroidKeyStore;
private PublicKey mPublicKey;
private byte[] mEncryptedSecretKey;
public CryptoHelper(Context context) {
mContext = context;
mSecureRandom = new SecureRandom();
mPrefs = mContext.getSharedPreferences(PREF_NAME, Context.MODE_PRIVATE);
try {
mAndroidKeyStore = KeyStore.getInstance(ANDROID_KEY_STORE);
mAndroidKeyStore.load(null);
} catch (KeyStoreException e) {
Log.wtf(TAG, "Could not get AndroidKeyStore!", e);
} catch (Exception e) {
Log.wtf(TAG, "Could not load AndroidKeyStore!", e);
}
}
public void reset() throws KeyStoreException {
mAndroidKeyStore.deleteEntry(KEY_ALIAS);
}
public byte[] encrypt(byte[] message){
SecretKey secretKey = getSecretKey();
try {
Cipher cipher = Cipher.getInstance(AES_MODE);
cipher.init(Cipher.ENCRYPT_MODE, getSecretKey());
byte[] cryptedBytes = cipher.doFinal(message);
byte[] iv = cipher.getIV();
byte[] encryptedSecretKey = getEncryptedSecretKey();
ByteBuffer buffer = ByteBuffer.allocate(IV_BIT_LEN + encryptedSecretKey.length + cryptedBytes.length);
buffer
.put(iv)
.put(encryptedSecretKey)
.put(cryptedBytes);
return buffer.array();
} catch (GeneralSecurityException e) {
e.printStackTrace();
}
return null;
}
public byte[] encrypt(String message){
return encrypt(message.getBytes(StandardCharsets.UTF_8));
}
public byte[] decrypt(byte[] bytes){
ByteBuffer buffer = ByteBuffer.wrap(bytes);
byte[] iv = new byte[IV_SIZE];
buffer.get(iv);
byte[] unused = getEncryptedSecretKey();
buffer.get(unused);
byte[] encryptedMessage = new byte[bytes.length - IV_SIZE - unused.length];
buffer.get(encryptedMessage);
try {
Cipher cipher = Cipher.getInstance(AES_MODE);
GCMParameterSpec parameterSpec = new GCMParameterSpec(IV_BIT_LEN, iv);
cipher.init(Cipher.DECRYPT_MODE, getSecretKey(), parameterSpec);
byte[] decryptedMessage = cipher.doFinal(encryptedMessage);
return decryptedMessage;
} catch (GeneralSecurityException e) {
e.printStackTrace();
}
return null;
}
public String decryptToString(byte[] bytes){
return new String(decrypt(bytes), StandardCharsets.UTF_8);
}
public byte[] decrypt(FileInputStream fileToDecrypt){
byte[] buffer = null;
try {
buffer = new byte[fileToDecrypt.available()];
fileToDecrypt.read(buffer);
buffer = decrypt(buffer);
} catch (IOException e) {
e.printStackTrace();
}
return buffer;
}
public PublicKey getPublicKey() {
if (null == mPublicKey) {
mPublicKey = readPublicKey();
}
return mPublicKey;
}
public byte[] getEncryptedSecretKey() {
if (null == mEncryptedSecretKey){
mEncryptedSecretKey = Base64.decode(mPrefs.getString(KEY_ENCRYPTED_SECRET, null), Base64.NO_WRAP);
}
return mEncryptedSecretKey;
}
private void saveEncryptedSecretKey(byte[] encryptedSecretKey){
String base64EncryptedKey = Base64.encodeToString(encryptedSecretKey, Base64.NO_WRAP);
mPrefs.edit().putString(KEY_ENCRYPTED_SECRET, base64EncryptedKey).apply();
}
protected SecretKey getSecretKey(){
SecretKey secretKey = null;
try {
if (!mAndroidKeyStore.containsAlias(KEY_ALIAS)){
generateAndStoreSecureKey();
}
secretKey = (SecretKey) mAndroidKeyStore.getKey(KEY_ALIAS, KEY_PASSWORD);
} catch (KeyStoreException e) {
Log.wtf(TAG, "Could not check AndroidKeyStore alias!", e);
secretKey = null;
} catch (GeneralSecurityException e) {
e.printStackTrace();
secretKey = null;
}
return secretKey;
}
private void generateAndStoreSecureKey()
throws NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeyException, KeyStoreException, BadPaddingException, IllegalBlockSizeException {
SecretKey secretKey = generateSecureRandomKey();
PublicKey publicKey = getPublicKey();
Cipher keyCipher = Cipher.getInstance(RSA_MODE, RSA_PROVIDER);
keyCipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] encryptedSecretKeyBytes = keyCipher.doFinal(secretKey.getEncoded());
saveEncryptedSecretKey(encryptedSecretKeyBytes);
KeyProtection keyProtection = new KeyProtection.Builder(KeyProperties.PURPOSE_DECRYPT | KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_VERIFY)
.setBlockModes(KeyProperties.BLOCK_MODE_GCM)
.setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_NONE)
.build();
mAndroidKeyStore.setEntry(KEY_ALIAS, new KeyStore.SecretKeyEntry(secretKey), keyProtection);
}
protected PublicKey readPublicKey() {
DataInputStream dis = null;
PublicKey key = null;
try {
dis = new DataInputStream(mContext.getResources().getAssets().open("public_key.der"));
byte[] keyBytes = new byte[dis.available()];
dis.readFully(keyBytes);
X509EncodedKeySpec spec = new X509EncodedKeySpec(keyBytes);
KeyFactory facotory = KeyFactory.getInstance(RSA);
key = facotory.generatePublic(spec);
} catch (Exception e) {
key = null;
} finally {
if (null != dis) {
try {
dis.close();
} catch (IOException e) {
Log.wtf(TAG, "Cannot Close Stream!", e);
}
}
}
return key;
}
#NonNull
protected SecretKey generateSecureRandomKey() {
return new SecretKeySpec(generateSecureRandomBytes(AES_KEY_SIZE), AES);
}
#NonNull
protected byte[] generateSecureRandomBytes(int byteCount) {
byte[] keyBytes = new byte[byteCount];
mSecureRandom.nextBytes(keyBytes);
return keyBytes;
}
}
And I Test it like this:
#Test
public void testCrypto() throws Exception {
CryptoHelper crypto = new CryptoHelper(InstrumentationRegistry.getTargetContext());
crypto.reset();
String verySecretOpinion = "we're all doomed";
byte[] encrypt = crypto.encrypt(verySecretOpinion);
Assert.assertNotNull("Encrypted secret is Null!", encrypt);
Assert.assertFalse("encrypted Bytes are the same as Input!", new String(encrypt, StandardCharsets.UTF_8).equals(verySecretOpinion));
String decryptedString = crypto.decryptToString(encrypt);
Assert.assertNotNull("Decrypted String must be Non-Null!", decryptedString);
Assert.assertEquals("Decrypted String doesn't equal encryption input!", verySecretOpinion, decryptedString);
}
By the way minSdkVersion is 25, so higher than Marshmallow
UPDATE:
Fixed Cipher.DECRYPT_MODE to ENCRYPT_MODE on saving the SecretKey thx to James K Polk's comment
it works If I switch from BlockMode GCM to BlockMode CBC (and changing the GCMParameterSpec to IvParamterSpec but loose the verification of the GCM Mode.
There are at least two problems with the Operator interface. First, you RSA encrypt the secret key using the wrong Cipher mode: you used DECRYPT mode when you should have used encrypt. Secondly, you are using RSA without any padding. You need to use a real padding mode, one of the OEAP padding modes is recommended.
An error in the encryption side occurs when sizing the buffer used to hold the result:
ByteBuffer buffer = ByteBuffer.allocate(IV_BIT_LEN + encryptedSecretKey.length + cryptedBytes.length);
allocates too much space. IV_BIT_LEN should probably be changed to IV_SIZE to get the correctly sized ByteBuffer.
The last mistake is the failure to account for the GCM authentication tag length when setting the GCMParameterSpec on the decrypt side. You initialized the tag length in this line
GCMParameterSpec parameterSpec = new GCMParameterSpec(IV_BIT_LEN, iv);
but that's incorrect, the tag length is unrelated to the IV. Since you did not explicitly set the GCMParameterSpec on the encrypt side you got the default tag length, which happens to be 128.
You can retrieve the tag length on the encrypt side by calling
cipher.getParameters().getParameterSpec(GCMParameterSpec.class) to get the parameter spec. From this you can retrieve both the tag length and the iv. You should probably consider the tag length, 16 bytes = 128 bits, to be a hard-coded constant and not transmit it. The receiver should similar assume the tag length is 128 bits.
I want to convert following C# to java code, so we can decrypt old messages and encrypt new ones in java.
public class encryptionUtil
{
private TripleDESCryptoServiceProvider TripleDes;
private UTF8Encoding utfEncoding;
private byte[] key;
private byte[] iv;
private string sysKey;
private string sysUser;
public encryptionUtil()
{
this.TripleDes = new TripleDESCryptoServiceProvider();
this.utfEncoding = new UTF8Encoding();
this.key = this.utfEncoding.GetBytes("123456789012345678901234");
this.iv = this.utfEncoding.GetBytes("12345678");
this.sysKey = WindowsIdentity.GetCurrent().Name;
this.sysUser = WindowsIdentity.GetCurrent().User.Value;
}
public string EncryptData(string plaintext)
{
string str;
try
{
plaintext = plaintext + this.sysUser;
byte[] bytes = Encoding.Unicode.GetBytes(plaintext);
MemoryStream memoryStream = new MemoryStream();
CryptoStream cryptoStream = new CryptoStream((Stream) memoryStream, this.TripleDes.CreateEncryptor(this.key, this.iv), CryptoStreamMode.Write);
cryptoStream.Write(bytes, 0, bytes.Length);
cryptoStream.FlushFinalBlock();
str = Convert.ToBase64String(memoryStream.ToArray());
}
catch (Exception ex)
{
ProjectData.SetProjectError(ex);
str = plaintext ;
ProjectData.ClearProjectError();
}
return str;
}
public string DecryptData(string encryptedtext)
{
string str;
try
{
byte[] buffer = Convert.FromBase64String(encryptedtext);
MemoryStream memoryStream = new MemoryStream();
CryptoStream cryptoStream = new CryptoStream((Stream) memoryStream, this.TripleDes.CreateDecryptor(this.key, this.iv), CryptoStreamMode.Write);
cryptoStream.Write(buffer, 0, buffer.Length);
cryptoStream.FlushFinalBlock();
string[] strArray = Encoding.Unicode.GetString(memoryStream.ToArray());
str = Microsoft.VisualBasic.CompilerServices.Operators.CompareString(strArray[1], this.token, false) != 0 ? "" : strArray[0];
}
catch (Exception ex)
{
ProjectData.SetProjectError(ex);
str = "";
ProjectData.ClearProjectError();
}
return str;
}
Encryption output in c# for "Encrypt this in java"
7UlYtjB6Nls4Q3Ac4VzdY2k6hVRa1Eqjyt2ZG4818WxLCwFhx1fEeTCvOStTylyMM5ucL4DmF1NKBRga44Yqrj89VHRKZuWnFC24jMkSxucZkB3niLa7WOT4GKlii7716w6TC9iJGYLhy8mY1kqwaw==
Java code written so far, how to proceed further so that I get same result as above?
package com.mycompany.util;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.GeneralSecurityException;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
public class EncryptionUtil {
private static SecretKey sharedkey;
private static byte [] sharedvector;
static {
int keySize = 168;
int ivSize = 8;
try {
KeyGenerator keyGenerator = KeyGenerator.getInstance("DESede");
keyGenerator.init(keySize);
sharedkey = keyGenerator.generateKey();
sharedvector = new byte [ivSize];
byte [] data = sharedkey.getEncoded();
int half = ivSize / 2;
System.arraycopy(data, data.length-half, sharedvector, 0, half);
System.arraycopy(sharedvector, 0, sharedvector, half, half);
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
}
public static void main(String [] args) throws Exception {
String plainText = "Encrypt this in java";
String systemId= "949367136-5890454";
String dataText = plainText+systemId
String keyString = "key1234";
String ivString = "iv1234";
try {
byte[] keyBytes = keyString.getBytes("UTF-8");
byte[] ivBytes = ivString.getBytes("UTF-8");
byte[] dataBytes = plainText.getBytes("UTF-8");
System.out.println("key="+keyBytes.toString());
System.out.println("iv="+ivBytes.toString());
System.out.println("plaintextBytesUTF-8="+dataBytes.toString());
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static String Encrypt(String val) throws GeneralSecurityException {
Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, sharedkey, new IvParameterSpec(sharedvector));
return new sun.misc.BASE64Encoder().encode(cipher.doFinal(val.getBytes()));
}
public static String Decrypt(String val) throws GeneralSecurityException, IOException {
Cipher cipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, sharedkey, new IvParameterSpec(sharedvector));
return new String(cipher.doFinal(new sun.misc.BASE64Decoder().decodeBuffer(val)));
}
}
I need to decrypt in JAVA a file encrypted in UNIX with the following command:
openssl aes-256-cbc -a -salt -in password.txt -out password.txt.enc
mypass
mypass
I have to decrypt in java as I do here I do in UNIX
openssl aes-256-cbc -d -a -in password.txt.enc -out password.txt.new
mypass
Someone can give me a java code to do this?
OpenSSL generally uses its own password based key derivation method, specified in EVP_BytesToKey, please see the code below. Furthermore, it implicitly encodes the ciphertext as base 64 over multiple lines, which would be required to send it within the body of a mail message.
So the result is, in pseudocode:
salt = random(8)
keyAndIV = BytesToKey(password, salt, 48)
key = keyAndIV[0..31]
iv = keyAndIV[32..47]
ct = AES-256-CBC-encrypt(key, iv, plaintext)
res = base64MimeEncode("Salted__" | salt | ct))
and the decryption therefore is:
(salt, ct) = base64MimeDecode(res)
key = keyAndIV[0..31]
iv = keyAndIV[32..47]
pt = AES-256-CBC-decrypt(key, iv, plaintext)
which can be implemented in Java like this:
import java.io.File;
import java.io.IOException;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.util.Arrays;
import java.util.List;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.util.encoders.Base64;
public class OpenSSLDecryptor {
private static final Charset ASCII = Charset.forName("ASCII");
private static final int INDEX_KEY = 0;
private static final int INDEX_IV = 1;
private static final int ITERATIONS = 1;
private static final int ARG_INDEX_FILENAME = 0;
private static final int ARG_INDEX_PASSWORD = 1;
private static final int SALT_OFFSET = 8;
private static final int SALT_SIZE = 8;
private static final int CIPHERTEXT_OFFSET = SALT_OFFSET + SALT_SIZE;
private static final int KEY_SIZE_BITS = 256;
/**
* Thanks go to Ola Bini for releasing this source on his blog.
* The source was obtained from here .
*/
public static byte[][] EVP_BytesToKey(int key_len, int iv_len, MessageDigest md,
byte[] salt, byte[] data, int count) {
byte[][] both = new byte[2][];
byte[] key = new byte[key_len];
int key_ix = 0;
byte[] iv = new byte[iv_len];
int iv_ix = 0;
both[0] = key;
both[1] = iv;
byte[] md_buf = null;
int nkey = key_len;
int niv = iv_len;
int i = 0;
if (data == null) {
return both;
}
int addmd = 0;
for (;;) {
md.reset();
if (addmd++ > 0) {
md.update(md_buf);
}
md.update(data);
if (null != salt) {
md.update(salt, 0, 8);
}
md_buf = md.digest();
for (i = 1; i < count; i++) {
md.reset();
md.update(md_buf);
md_buf = md.digest();
}
i = 0;
if (nkey > 0) {
for (;;) {
if (nkey == 0)
break;
if (i == md_buf.length)
break;
key[key_ix++] = md_buf[i];
nkey--;
i++;
}
}
if (niv > 0 && i != md_buf.length) {
for (;;) {
if (niv == 0)
break;
if (i == md_buf.length)
break;
iv[iv_ix++] = md_buf[i];
niv--;
i++;
}
}
if (nkey == 0 && niv == 0) {
break;
}
}
for (i = 0; i < md_buf.length; i++) {
md_buf[i] = 0;
}
return both;
}
public static void main(String[] args) {
try {
// --- read base 64 encoded file ---
File f = new File(args[ARG_INDEX_FILENAME]);
List<String> lines = Files.readAllLines(f.toPath(), ASCII);
StringBuilder sb = new StringBuilder();
for (String line : lines) {
sb.append(line.trim());
}
String dataBase64 = sb.toString();
byte[] headerSaltAndCipherText = Base64.decode(dataBase64);
// --- extract salt & encrypted ---
// header is "Salted__", ASCII encoded, if salt is being used (the default)
byte[] salt = Arrays.copyOfRange(
headerSaltAndCipherText, SALT_OFFSET, SALT_OFFSET + SALT_SIZE);
byte[] encrypted = Arrays.copyOfRange(
headerSaltAndCipherText, CIPHERTEXT_OFFSET, headerSaltAndCipherText.length);
// --- specify cipher and digest for EVP_BytesToKey method ---
Cipher aesCBC = Cipher.getInstance("AES/CBC/PKCS5Padding");
MessageDigest md5 = MessageDigest.getInstance("MD5");
// --- create key and IV ---
// the IV is useless, OpenSSL might as well have use zero's
final byte[][] keyAndIV = EVP_BytesToKey(
KEY_SIZE_BITS / Byte.SIZE,
aesCBC.getBlockSize(),
md5,
salt,
args[ARG_INDEX_PASSWORD].getBytes(ASCII),
ITERATIONS);
SecretKeySpec key = new SecretKeySpec(keyAndIV[INDEX_KEY], "AES");
IvParameterSpec iv = new IvParameterSpec(keyAndIV[INDEX_IV]);
// --- initialize cipher instance and decrypt ---
aesCBC.init(Cipher.DECRYPT_MODE, key, iv);
byte[] decrypted = aesCBC.doFinal(encrypted);
String answer = new String(decrypted, ASCII);
System.out.println(answer);
} catch (BadPaddingException e) {
// AKA "something went wrong"
throw new IllegalStateException(
"Bad password, algorithm, mode or padding;" +
" no salt, wrong number of iterations or corrupted ciphertext.");
} catch (IllegalBlockSizeException e) {
throw new IllegalStateException(
"Bad algorithm, mode or corrupted (resized) ciphertext.");
} catch (GeneralSecurityException e) {
throw new IllegalStateException(e);
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
}
Beware that the code specifies ASCII as character set. The character set used may differ for your application / terminal / OS.
In general you should force OpenSSL to use the NIST approved PBKDF2 algorithm, as using the OpenSSL key derivation method - with an iteration count of 1 - is insecure. This may force you to use a different solution than OpenSSL. Note that password based encryption is inherently rather insecure - passwords are much less secure than randomly generated symmetric keys.
OpenSSL 1.1.0c changed the digest algorithm used in some internal components. Formerly, MD5 was used, and 1.1.0 switched to SHA256. Be careful the change is not affecting you in both EVP_BytesToKey and commands like openssl enc.
It's probably best to explicitly specify the digest in the command line interface (e.g. -md md5 for backwards compatibility or sha-256 for forwards compatibility) for the and make sure that the Java code uses the same digest algorithm ("MD5" or "SHA-256" including the dash). Also see the information in this answer.
Below are OpenSSLPBEInputStream and OpenSSLPBEOutputStream which can be used to encrypt/decrypt arbitrary streams of bytes in a way that is compatible with OpenSSL.
Example usage:
// The original clear text bytes
byte[] originalBytes = ...
// Encrypt these bytes
char[] pwd = "thePassword".toCharArray();
ByteArrayOutputStream byteOS = new ByteArrayOutputStream();
OpenSSLPBEOutputStream encOS = new OpenSSLPBEOutputStream(byteOS, ALGORITHM, 1, pwd);
encOS.write(originalBytes);
encOS.flush();
byte[] encryptedBytes = byteOS.toByteArray();
// Decrypt the bytes
ByteArrayInputStream byteIS = new ByteArrayInputStream(encryptedBytes);
OpenSSLPBEInputStream encIS = new OpenSSLPBEInputStream(byteIS, ALGORITHM, 1, pwd);
Where ALGORITHM (using just JDK classes) can be: "PBEWithMD5AndDES", "PBEWithMD5AndTripleDES", "PBEWithSHA1AndDESede", "PBEWithSHA1AndRC2_40".
To handle "openssl aes-256-cbc -a -salt -in password.txt -out password.txt.enc" of the original poster, add bouncey castle to the classpath, and use algorthm= "PBEWITHMD5AND256BITAES-CBC-OPENSSL".
/* Add BC provider, and fail fast if BC provider is not in classpath for some reason */
Security.addProvider(new BouncyCastleProvider());
The dependency:
<dependency>
<groupId>org.bouncycastle</groupId>
<artifactId>bcprov-jdk16</artifactId>
<version>1.44</version>
</dependency>
The input stream:
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import java.io.IOException;
import java.io.InputStream;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
public class OpenSSLPBEInputStream extends InputStream {
private final static int READ_BLOCK_SIZE = 64 * 1024;
private final Cipher cipher;
private final InputStream inStream;
private final byte[] bufferCipher = new byte[READ_BLOCK_SIZE];
private byte[] bufferClear = null;
private int index = Integer.MAX_VALUE;
private int maxIndex = 0;
public OpenSSLPBEInputStream(final InputStream streamIn, String algIn, int iterationCount, char[] password)
throws IOException {
this.inStream = streamIn;
try {
byte[] salt = readSalt();
cipher = OpenSSLPBECommon.initializeCipher(password, salt, Cipher.DECRYPT_MODE, algIn, iterationCount);
} catch (InvalidKeySpecException | NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException | InvalidAlgorithmParameterException e) {
throw new IOException(e);
}
}
#Override
public int available() throws IOException {
return inStream.available();
}
#Override
public int read() throws IOException {
if (index > maxIndex) {
index = 0;
int read = inStream.read(bufferCipher);
if (read != -1) {
bufferClear = cipher.update(bufferCipher, 0, read);
}
if (read == -1 || bufferClear == null || bufferClear.length == 0) {
try {
bufferClear = cipher.doFinal();
} catch (IllegalBlockSizeException | BadPaddingException e) {
bufferClear = null;
}
}
if (bufferClear == null || bufferClear.length == 0) {
return -1;
}
maxIndex = bufferClear.length - 1;
}
return bufferClear[index++] & 0xff;
}
private byte[] readSalt() throws IOException {
byte[] headerBytes = new byte[OpenSSLPBECommon.OPENSSL_HEADER_STRING.length()];
inStream.read(headerBytes);
String headerString = new String(headerBytes, OpenSSLPBECommon.OPENSSL_HEADER_ENCODE);
if (!OpenSSLPBECommon.OPENSSL_HEADER_STRING.equals(headerString)) {
throw new IOException("unexpected file header " + headerString);
}
byte[] salt = new byte[OpenSSLPBECommon.SALT_SIZE_BYTES];
inStream.read(salt);
return salt;
}
}
The output stream:
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import java.io.IOException;
import java.io.OutputStream;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;
public class OpenSSLPBEOutputStream extends OutputStream {
private static final int BUFFER_SIZE = 5 * 1024 * 1024;
private final Cipher cipher;
private final OutputStream outStream;
private final byte[] buffer = new byte[BUFFER_SIZE];
private int bufferIndex = 0;
public OpenSSLPBEOutputStream(final OutputStream outputStream, String algIn, int iterationCount,
char[] password) throws IOException {
outStream = outputStream;
try {
/* Create and use a random SALT for each instance of this output stream. */
byte[] salt = new byte[PBECommon.SALT_SIZE_BYTES];
new SecureRandom().nextBytes(salt);
cipher = OpenSSLPBECommon.initializeCipher(password, salt, Cipher.ENCRYPT_MODE, algIn, iterationCount);
/* Write header */
writeHeader(salt);
} catch (InvalidKeySpecException | NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException | InvalidAlgorithmParameterException e) {
throw new IOException(e);
}
}
#Override
public void write(int b) throws IOException {
buffer[bufferIndex] = (byte) b;
bufferIndex++;
if (bufferIndex == BUFFER_SIZE) {
byte[] result = cipher.update(buffer, 0, bufferIndex);
outStream.write(result);
bufferIndex = 0;
}
}
#Override
public void flush() throws IOException {
if (bufferIndex > 0) {
byte[] result;
try {
result = cipher.doFinal(buffer, 0, bufferIndex);
outStream.write(result);
} catch (IllegalBlockSizeException | BadPaddingException e) {
throw new IOException(e);
}
bufferIndex = 0;
}
}
#Override
public void close() throws IOException {
flush();
outStream.close();
}
private void writeHeader(byte[] salt) throws IOException {
outStream.write(OpenSSLPBECommon.OPENSSL_HEADER_STRING.getBytes(OpenSSLPBECommon.OPENSSL_HEADER_ENCODE));
outStream.write(salt);
}
}
Small common class:
import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.PBEParameterSpec;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
class OpenSSLPBECommon {
protected static final int SALT_SIZE_BYTES = 8;
protected static final String OPENSSL_HEADER_STRING = "Salted__";
protected static final String OPENSSL_HEADER_ENCODE = "ASCII";
protected static Cipher initializeCipher(char[] password, byte[] salt, int cipherMode,
final String algorithm, int iterationCount) throws NoSuchAlgorithmException, InvalidKeySpecException,
InvalidKeyException, NoSuchPaddingException, InvalidAlgorithmParameterException {
PBEKeySpec keySpec = new PBEKeySpec(password);
SecretKeyFactory factory = SecretKeyFactory.getInstance(algorithm);
SecretKey key = factory.generateSecret(keySpec);
Cipher cipher = Cipher.getInstance(algorithm);
cipher.init(cipherMode, key, new PBEParameterSpec(salt, iterationCount));
return cipher;
}
}
In Kotlin:
package io.matthewnelson.java_crypto
import java.util.*
import javax.crypto.Cipher
import javax.crypto.SecretKeyFactory
import javax.crypto.spec.IvParameterSpec
import javax.crypto.spec.PBEKeySpec
import javax.crypto.spec.SecretKeySpec
class OpenSSL {
/**
* Will decrypt a string value encrypted by OpenSSL v 1.1.1+ using the following cmds from terminal:
*
* echo "Hello World!" | openssl aes-256-cbc -e -a -p -salt -pbkdf2 -iter 15739 -k qk4aX-EfMUa-g4HdF-fjfkU-bbLNx-15739
*
* Terminal output:
* salt=CC73B7D29FE59CE1
* key=31706F84185EA4B5E8E040F2C813F79722F22996B48B82FF98174F887A9B9993
* iv =1420310D41FD7F48E5D8722B9AC1C8DD
* U2FsdGVkX1/Mc7fSn+Wc4XLwDsmLdR8O7K3bFPpCglA=
* */
fun decrypt_AES256CBC_PBKDF2_HMAC_SHA256(
password: String,
hashIterations: Int,
encryptedString: String
): String {
val encryptedBytes = Base64.getDecoder().decode(encryptedString)
// Salt is bytes 8 - 15
val salt = encryptedBytes.copyOfRange(8, 16)
// println("Salt: ${salt.joinToString("") { "%02X".format(it) }}")
// Derive 48 byte key
val keySpec = PBEKeySpec(password.toCharArray(), salt, hashIterations, 48 * 8)
val keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256")
val secretKey = keyFactory.generateSecret(keySpec)
// Decryption Key is bytes 0 - 31 of the derived key
val key = secretKey.encoded.copyOfRange(0, 32)
// println("Key: ${key.joinToString("") { "%02X".format(it) }}")
// Input Vector is bytes 32 - 47 of the derived key
val iv = secretKey.encoded.copyOfRange(32, 48)
// println("IV: ${iv.joinToString("") { "%02X".format(it) }}")
// Cipher Text is bytes 16 - end of the encrypted bytes
val cipherText = encryptedBytes.copyOfRange(16, encryptedBytes.lastIndex + 1)
// Decrypt the Cipher Text and manually remove padding after
val cipher = Cipher.getInstance("AES/CBC/NoPadding")
cipher.init(Cipher.DECRYPT_MODE, SecretKeySpec(key, "AES"), IvParameterSpec(iv))
val decrypted = cipher.doFinal(cipherText)
// println("Decrypted: ${decrypted.joinToString("") { "%02X".format(it) }}")
// Last byte of the decrypted text is the number of padding bytes needed to remove
val plaintext = decrypted.copyOfRange(0, decrypted.lastIndex + 1 - decrypted.last().toInt())
return plaintext.toString(Charsets.UTF_8)
}
}
Don't use ase-128-cbc, use ase-128-ecb.
only take first 16 bytes as key because key is 128 bits
hash output is printed in hex, which every 2 chars presents a byte value
hashpwd=echo -n $password| openssl sha1 | sed 's#.*=\\s*##g' | cut -c 1-32
openssl enc -aes-128-ecb -salt -in -out -K $hashpwd
Java Code is here:
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import java.io.*;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
//openssl enc -nosalt -aes-128-ecb
// -in <input file>
// -out <output file>
// -K <16 bytes in hex, for example : "abc" can be hashed in SHA-1, the first 16 bytes in hex is a9993e364706816aba3e25717850c26c>
private final static String TRANSFORMATION = "AES"; // use aes-128-ecb in openssl
public static byte[] encrypt(String passcode, byte[] data) throws CryptographicException {
try {
Cipher cipher = Cipher.getInstance(TRANSFORMATION);
cipher.init(Cipher.ENCRYPT_MODE, genKeySpec(passcode));
return cipher.doFinal(data);
} catch (Exception ex) {
throw new CryptographicException("Error encrypting", ex);
}
}
public static String encryptWithBase64(String passcode, byte[] data) throws CryptographicException {
return new BASE64Encoder().encode(encrypt(passcode, data));
}
public static byte[] decrypt(String passcode, byte[] data) throws CryptographicException {
try {
Cipher dcipher = Cipher.getInstance(TRANSFORMATION);
dcipher.init(Cipher.DECRYPT_MODE, genKeySpec(passcode));
return dcipher.doFinal(data);
} catch (Exception e) {
throw new CryptographicException("Error decrypting", e);
}
}
public static byte[] decryptWithBase64(String passcode, String encrptedStr) throws CryptographicException {
try {
return decrypt(passcode, new BASE64Decoder().decodeBuffer(encrptedStr));
} catch (Exception e) {
throw new CryptographicException("Error decrypting", e);
}
}
public static SecretKeySpec genKeySpec(String passcode) throws UnsupportedEncodingException, NoSuchAlgorithmException {
byte[] key = passcode.getBytes("UTF-8");
MessageDigest sha = MessageDigest.getInstance("SHA-1");
key = sha.digest(key);
key = Arrays.copyOf(key, 16); // use only first 128 bit
return new SecretKeySpec(key, TRANSFORMATION);
}
Tested and passed in jdk6 and jdk8.
Thanx to evry one help me ..but still there is 2 problem after editing the code
import java.io.*;
import java.math.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
public class RCC4 {
public RCC4(){}
public static void main(String[] args)throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IOException{
String test = "testisperfect";
System.out.println(RCC4.keyGet());
byte b[] = RCC4.keyGet().getBytes();
byte plain[] = test.getBytes();
**byte c[] = RCC4.encrypt(plain,b);**
**byte p[] = RCC4.decrypt(c,b);**
**System.out.println(new String(c)) ;
System.out.println(new String(p));**
}
public static byte[] encrypt(byte[] plaintext,byte[] keyBytes)
{
byte[] e = null;
try
{
Key key = new SecretKeySpec(keyBytes,"RC4");
Cipher enCipher = Cipher.getInstance("RC4");
**enCipher.init(Cipher.ENCRYPT_MODE ,key);**
e = enCipher.doFinal(plaintext);
}
catch(Exception ex)
{
ex.printStackTrace();
}
return e;
}
public static byte[] decrypt(byte[] ciphertext,byte[] keyBytes)
{
byte de[] = null;
try
{
Key key = new SecretKeySpec(keyBytes,"RC4");
Cipher deCipher = Cipher.getInstance("RC4");
**deCipher.init(Cipher.DECRYPT_MODE, key);**
de = deCipher.doFinal(ciphertext);
}
catch(Exception e)
{
e.printStackTrace();
}
return de;
}
public static Key getKey()
{
Key key = null;
try
{
SecureRandom sr = new SecureRandom();
KeyGenerator kg = KeyGenerator.getInstance("RC4");
kg.init(128,sr);
key = kg.generateKey();
}catch(Exception e)
{
e.printStackTrace();
}
return key;
}
public static String keyGet()
{
Key k = RCC4.getKey();
byte[] b = k.getEncoded();
BigInteger big = new BigInteger(b);
String s = big.toString();
return s;
}
}
When I press "Build file" it says process completed but at running file a message says
112670544188765215715791498302542646231
java.security.InvalidKeyException: Illegal key size or default parameters
at RCC4.encrypt(RCC4.java:37)
at RCC4.main(RCC4.java:23)
java.security.InvalidKeyException: Illegal key size or default parameters
at RCC4.decrypt(RCC4.java:53)
at RCC4.main(RCC4.java:24)
Exception in thread "main" java.lang.NullPointerException
at java.lang.String.<init>(String.java:479)
at RCC4.main(RCC4.java:26)
Process completed.
These Lines are indicated as *
Answer to original question:
Key key = new SecretKeySpec(byte[]keyBytes,RC4);
should be
Key key = new SecretKeySpec(keyBytes, "RC4");
Also,
deCipher.init(Cipher.WHATEVER, keyBytes);
should be
deCipher.init(Cipher.WHATEVER, key);
Then it compiles, however there's still some issue with the application logic. That's up to you again :).
Answer to new question:
The problem was the unneeded usage of SecretKeySpec. Somewhere between getKey(), keyGet() all the byte[] games and SecretKeySpec it got wrong somehow. I didn't have the patience to track it, so I just deleted it and made the code somewhat more readable to make sure I didn't miss anything. I think you will still understand it since it still is basically your code and it is much simpler now.
import java.security.*;
import javax.crypto.*;
public class RCC4 {
public static void main(String[] args) throws Exception {
String plain = "testisperfect";
Key key = RCC4.getKey();
String encrypted = RCC4.encrypt(plain, key);
String decrypted = RCC4.decrypt(encrypted, key);
System.out.println(encrypted);
System.out.println(decrypted);
}
private static String rc4(String plaintext, int mode, Key key) throws Exception {
Cipher cipher = Cipher.getInstance("RC4");
cipher.init(mode, key);
return new String(cipher.doFinal(plaintext.getBytes()));
}
public static String encrypt(String plaintext, Key key) throws Exception {
return rc4(plaintext, Cipher.ENCRYPT_MODE, key);
}
public static String decrypt(String ciphertext, Key key) throws Exception {
return rc4(ciphertext, Cipher.DECRYPT_MODE, key);
}
public static Key getKey() throws Exception {
KeyGenerator kg = KeyGenerator.getInstance("RC4");
SecureRandom sr = new SecureRandom();
kg.init(128, sr);
return kg.generateKey();
}
}
You need import SecretKeySpec which is under package javax.crypto.spec.
You're not calling the method correctly in that you're passing in the parameter type with the parameter. Parameter types are only shown when declaring a method, not when calling the method.
In other words, it's not
Key key = new SecretKeySpec(byte[] keyBytes, RC4);
it's instead
Key key = new SecretKeySpec(keyBytes, RC4);
You will of course need to have a keyBytes variable declared and initialized before trying to pass it into the parameter of this method.
package test;
import java.io.*;
import java.math.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;
public class RCC4 {
public RCC4() {
}
public static void main(String[] args) throws NoSuchAlgorithmException,
NoSuchPaddingException, InvalidKeyException, IOException {
String test = "testisperfect";
System.out.println(RCC4.keyGet());
byte b[] = RCC4.keyGet().getBytes();
byte plain[] = test.getBytes();
byte c[] = RCC4.encrypt(plain, b);
byte p[] = RCC4.decrypt(c, b);
System.out.println(new String(c));
System.out.println(new String(p));
}
public static byte[] encrypt(byte[] plaintext, byte[] keyBytes) {
byte[] e = null;
try {
Key key = new SecretKeySpec(keyBytes, "RC4");
Cipher enCipher = Cipher.getInstance("RC4");
enCipher.init(Cipher.ENCRYPT_MODE, key);
e = enCipher.doFinal(plaintext);
} catch (Exception ex) {
ex.printStackTrace();
}
return e;
}
public static byte[] decrypt(byte[] ciphertext, byte[] keyBytes) {
byte de[] = null;
try {
Key key = new SecretKeySpec(keyBytes, "RC4");
Cipher deCipher = Cipher.getInstance("RC4");
deCipher.init(Cipher.DECRYPT_MODE, RCC4.getKey());
de = deCipher.doFinal(ciphertext);
} catch (Exception e) {
e.printStackTrace();
}
return de;
}
public static Key getKey() {
Key key = null;
try {
SecureRandom sr = new SecureRandom();
KeyGenerator kg = KeyGenerator.getInstance("RC4");
kg.init(128, sr);
key = kg.generateKey();
} catch (Exception e) {
e.printStackTrace();
}
return key;
}
public static String keyGet() {
Key k = RCC4.getKey();
byte[] b = k.getEncoded();
BigInteger big = new BigInteger(b);
String s = big.toString();
return s;
}
}