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파일을 암호화하고 해독 할 수있는 몇 가지 방법이 있습니다. 내가 아는 한 내 암호화 기능은 훌륭하게 작동하지만 해독은 대개 InvalidKeyException, 특히 Cipher.getInstance("AES"); 비트를 던졌습니다. 나는 이걸 RSA에서 "RSA/CBC/PKCS5Padding"으로 바꾸었지만 지금까지 아무 일도 없었다.AES 키를 해독하는 중에 잘못된 키 예외가 발생했습니다.
주요 기능 :
static String inFile = "";
static String outFile = "";
static String hexKey="";
static String keyStore;
static String keyName;
public static void main(String[] args) {
if (args.length==5 && args[0].equals("-encRSA")) {
keyStore = args[1];
keyName = args[2];
inFile = args[3];
outFile = args[4];
encryptRSA();
} else if (args.length==5 && args[0].equals("-decRSA")) {
keyStore = args[1];
keyName = args[2];
inFile = args[3];
outFile = args[4];
decryptRSA();
} else {
System.out.println("This is a simple program to encrypt and decrypt files");
System.out.println("Usage: ");
System.out.println(" -encRSA <keyStore> <keyName> <inputFile> <outputFile> RSA encrypt");
System.out.println(" -decRSA <keyStore> <keyName> <inputFile> <outputFile> RSA decrypt");
}
암호화 기능 (지금까지)
private static void encryptRSA() {
try {
//Get the public key from the keyStore and set up the Cipher object
PublicKey publicKey = getPubKey(keyStore,keyName);
Cipher rsaCipher = Cipher.getInstance("RSA");
rsaCipher.init(Cipher.ENCRYPT_MODE, publicKey);
//Read the plainText
System.out.println("Loading plaintext file: "+inFile);
RandomAccessFile rawDataFromFile = new RandomAccessFile(inFile, "r");
byte[] plainText = new byte[(int)rawDataFromFile.length()];
rawDataFromFile.read(plainText);
// Generate a symmetric key to encrypt the data and initiate the AES Cipher Object
System.out.println("Generating AES key");
KeyGenerator sKenGen = KeyGenerator.getInstance("AES"); //ECB is fine here
Key aesKey = sKenGen.generateKey();
Cipher aesCipher = Cipher.getInstance("AES");
aesCipher.init(Cipher.ENCRYPT_MODE, aesKey);
// Encrypt the symmetric AES key with the public RSA key
System.out.println("Encrypting Data");
byte[] encodedKey = rsaCipher.doFinal(aesKey.getEncoded());
// Encrypt the plaintext with the AES key
byte[] cipherText = aesCipher.doFinal(plainText);
//Write the encrypted AES key and Ciphertext to the file.
System.out.println("Writting to file: "+outFile);
FileOutputStream outToFile = new FileOutputStream(outFile);
outToFile.write(encodedKey);
outToFile.write(cipherText);
System.out.println("Closing Files");
rawDataFromFile.close();
outToFile.close();
}
catch (Exception e) {
System.out.println("Doh: "+e);
}
}
해독 기능 :
private static void decryptRSA()
{
FileInputStream cipherfile;
try {
cipherfile = new FileInputStream(inFile);
byte[] ciphertext = new byte[cipherfile.available()];
PrivateKey privatekey = getKeyPair().getPrivate();
/* Create cipher for decryption. */
Cipher decrypt_cipher = Cipher.getInstance("AES");
decrypt_cipher.init(Cipher.DECRYPT_MODE, privatekey);
/* Reconstruct the plaintext message. */
byte[] plaintext = decrypt_cipher.doFinal(ciphertext);
FileOutputStream plainfile = new FileOutputStream(outFile);
plainfile.write(plaintext);
plainfile.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private static KeyPair getKeyPair() throws Exception
{
KeyPair keypair = null;
FileInputStream is = new FileInputStream(keyStore);
KeyStore keystore = KeyStore.getInstance(KeyStore.getDefaultType());
keystore.load(is, password.toCharArray());
Key key = keystore.getKey(keyName, password.toCharArray());
if (key instanceof PrivateKey) {
Certificate cert = keystore.getCertificate(keyName);
PublicKey publicKey = cert.getPublicKey();
keypair = new KeyPair(publicKey, (PrivateKey) key);
}
return keypair;
}