我一直在研究这个问题太久了。按照这个速度,我不会留下任何头发。我有一种情况,我正在尝试使用c ++进行加密并使用java进行解密,我认为使用像AES这样的标准会很容易,或者我认为。这是代码
加密的c ++在java代码中无法正确解密。
使用crypto ++的C ++
byte key[ CryptoPP::AES::MAX_KEYLENGTH ], iv[ CryptoPP::AES::BLOCKSIZE ];
memset( key, 0x00, CryptoPP::AES::MAX_KEYLENGTH );
memset( iv, 0x00, CryptoPP::AES::BLOCKSIZE );
string plaintext = "this is a test string";
string ciphertext;
string decryptedtext;
CryptoPP::AES::Encryption aesEncryption(key, CryptoPP::AES::MAX_KEYLENGTH);
CryptoPP::CBC_Mode_ExternalCipher::Encryption cbcEncryption( aesEncryption, iv );
CryptoPP::StreamTransformationFilter stfEncryptor(cbcEncryption, new CryptoPP::StringSink( ciphertext ) );
stfEncryptor.Put( reinterpret_cast<const unsigned char*>( plaintext.c_str() ), plaintext.length() + 1 );
stfEncryptor.MessageEnd();
std::cout << "Cipher Text (" << ciphertext() << " bytes)" << std::endl;
我的android / java代码 - MainActivity.java
String sEncryptedMsg = "paste encrypted string here from crypto++";
try {
String messageAfterDecrypt = AESCrypt.decrypt(password, sEncryptedMsg);
Log.i("decrypted --> ", messageAfterDecrypt);
}catch (GeneralSecurityException e){
}
Android / java代码 - AESCrypt.java
import android.util.Base64;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public final class AESCrypt
{
private static final String TAG = "AESCrypt";
//AESCrypt-ObjC uses CBC and PKCS7Padding
private static final String AES_MODE = "AES/CBC/PKCS7Padding";
private static final String CHARSET = "UTF-8";
//AESCrypt-ObjC uses SHA-256 (and so a 256-bit key)
private static final String HASH_ALGORITHM = "SHA-256";
//AESCrypt-ObjC uses blank IV (not the best security, but the aim here is compatibility)
private static final byte[] ivBytes = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
//togglable log option (please turn off in live!)
public static boolean DEBUG_LOG_ENABLED = false;
/**
* Generates SHA256 hash of the password which is used as key
*
* @param password used to generated key
* @return SHA256 of the password
*/
private static SecretKeySpec generateKey(final String password) throws NoSuchAlgorithmException, UnsupportedEncodingException {
final MessageDigest digest = MessageDigest.getInstance(HASH_ALGORITHM);
byte[] bytes = password.getBytes("UTF-8");
digest.update(bytes, 0, bytes.length);
byte[] key = digest.digest();
log("SHA-256 key ", key);
SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
return secretKeySpec;
}
/**
* Encrypt and encode message using 256-bit AES with key generated from password.
*
*
* @param password used to generated key
* @param message the thing you want to encrypt assumed String UTF-8
* @return Base64 encoded CipherText
* @throws GeneralSecurityException if problems occur during encryption
*/
/**
* Decrypt and decode ciphertext using 256-bit AES with key generated from password
*
* @param password used to generated key
* @param base64EncodedCipherText the encrpyted message encoded with base64
* @return message in Plain text (String UTF-8)
* @throws GeneralSecurityException if there's an issue decrypting
*/
public static String decrypt(final String password, String base64EncodedCipherText)
throws GeneralSecurityException {
try {
final SecretKeySpec key = generateKey(password);
log("base64EncodedCipherText", base64EncodedCipherText);
byte[] decodedCipherText = Base64.decode(base64EncodedCipherText, Base64.NO_WRAP);
log("decodedCipherText", decodedCipherText);
byte[] decryptedBytes = decrypt(key, ivBytes, decodedCipherText);
log("decryptedBytes", decryptedBytes);
String message = new String(decryptedBytes, CHARSET);
log("message", message);
return message;
} catch (UnsupportedEncodingException e) {
if (DEBUG_LOG_ENABLED)
Log.e(TAG, "UnsupportedEncodingException ", e);
throw new GeneralSecurityException(e);
}
}
/**
* More flexible AES decrypt that doesn't encode
*
* @param key AES key typically 128, 192 or 256 bit
* @param iv Initiation Vector
* @param decodedCipherText in bytes (assumed it's already been decoded)
* @return Decrypted message cipher text (not encoded)
* @throws GeneralSecurityException if something goes wrong during encryption
*/
public static byte[] decrypt(final SecretKeySpec key, final byte[] iv, final byte[] decodedCipherText)
throws GeneralSecurityException {
final Cipher cipher = Cipher.getInstance(AES_MODE);
IvParameterSpec ivSpec = new IvParameterSpec(iv);
cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);
byte[] decryptedBytes = cipher.doFinal(decodedCipherText);
log("decryptedBytes", decryptedBytes);
return decryptedBytes;
}
private static void log(String what, byte[] bytes) {
if (DEBUG_LOG_ENABLED)
Log.d(TAG, what + "[" + bytes.length + "] [" + bytesToHex(bytes) + "]");
}
private static void log(String what, String value) {
if (DEBUG_LOG_ENABLED)
Log.d(TAG, what + "[" + value.length() + "] [" + value + "]");
}
/**
* Converts byte array to hexidecimal useful for logging and fault finding
* @param bytes
* @return
*/
private static String bytesToHex(byte[] bytes) {
final char[] hexArray = {'0', '1', '2', '3', '4', '5', '6', '7', '8',
'9', 'A', 'B', 'C', 'D', 'E', 'F'};
char[] hexChars = new char[bytes.length * 2];
int v;
for (int j = 0; j < bytes.length; j++) {
v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
private AESCrypt() {
}
提前感谢您提供的任何帮助!