使用Java实现RSA加密/解密
我正在做一个简单的程序来加密/解密使用RSA算法在Java中。我创建了一个密码对象,如下所示:使用Java实现RSA加密/解密,java,cryptography,rsa,Java,Cryptography,Rsa,我正在做一个简单的程序来加密/解密使用RSA算法在Java中。我创建了一个密码对象,如下所示: //Create a Cipher object Cipher rsaCipher = Cipher.getInstance("RSA/ECB/NoPadding"); 我通过调用encrypt函数进行加密: String cipher=encrypt(textByte, pair, rsaCipher); System.out.println("The Encryption using RSA A
//Create a Cipher object
Cipher rsaCipher = Cipher.getInstance("RSA/ECB/NoPadding");
我通过调用encrypt函数进行加密:
String cipher=encrypt(textByte, pair, rsaCipher);
System.out.println("The Encryption using RSA Algorithm : "+cipher);
解密过程如下:
//Decryption
String plain=decrypt(Base64.decodeBase64(cipher),pair, rsaCipher);
System.out.println("The Decryption using RSA Algorithm : "+plain);
显示输出时,解密输出在原始文本之前返回一个长空格:
但是,当我编辑创建密码对象的代码时:
//创建一个密码对象
Cipher rsapier=Cipher.getInstance(“RSA”)
i、 e,删除操作模式和填充参数,问题得到解决,输出变为:
问题在哪里。在第一种情况下(当空格出现时),我指定了添加?为什么解密的邮件中会出现空格?即使我使用了填充物,我希望这种情况不会发生
编辑:
这是加密和解密方法:
public static String encrypt(byte[] textBytes, KeyPair pair, Cipher rsaCipher) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException
{
//get the public key
PublicKey pk=pair.getPublic();
//Initialize the cipher for encryption. Use the public key.
rsaCipher.init(Cipher.ENCRYPT_MODE, pk);
//Perform the encryption using doFinal
byte[] encByte = rsaCipher.doFinal(textBytes);
// converts to base64 for easier display.
byte[] base64Cipher = Base64.encodeBase64(encByte);
return new String(base64Cipher);
}//end encrypt
public static String decrypt(byte[] cipherBytes, KeyPair pair, Cipher rsaCipher) throws IllegalBlockSizeException, BadPaddingException, InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException
{
//get the public key
PrivateKey pvk=pair.getPrivate();
//Create a Cipher object
//Cipher rsaCipher = Cipher.getInstance("RSA/ECB/NoPadding");
//Initialize the cipher for encryption. Use the public key.
rsaCipher.init(Cipher.DECRYPT_MODE, pvk);
//Perform the encryption using doFinal
byte[] decByte = rsaCipher.doFinal(cipherBytes);
return new String(decByte);
}//end decrypt
你的问题确实在于填充物。安全的RSA功能需要某种填充,PKCS#1 1.5或OAEP填充。此外,还需要找到加密纯文本的开始和结束 RSA的模幂运算是使用大整数执行的。然后,这些操作的结果表示为八位字节字符串。这些八进制字符串基本上是整数的大端、无符号、固定长度表示。这些整数用
00
值字节填充(在RSA标准中称为I2OS原语)。因此,您看到的是模幂运算的结果,00
填充仍然存在
长话短说,始终使用填充方案。如今,OAEP更可取。将其与混合加密方案一起使用,或使用更高级别的容器格式,如CMS或PGP。能否向我们展示您的
加密
和解密
方法?
//This is a complete encryption and decryption module using
//Algorithm: JWEAlgorithm.RSA_OAEP_256
//Encryption Method: A128CBC_HS256
public static String encrypt(String text) throws Exception {
// Set the plain text
Payload payload = new Payload(text);
// Create the header
JWEHeader header = new JWEHeader(JWEAlgorithm.RSA_OAEP_256, EncryptionMethod.A128CBC_HS256);
// Create the JWE object and encrypt it
JWEObject jweObject = new JWEObject(header, payload);
jweObject.encrypt(new RSAEncrypter(getPublicKey()));
// Serialise to compact JOSE form...
String jweString = jweObject.serialize();
LOG.info("Generated Encrypted Key : {}", jweString);
return jweString;
}
public static String decrypt(String text) throws Exception {
// Parse into JWE object...
JWEObject jweObject = JWEObject.parse(text);
jweObject.decrypt(new RSADecrypter(getPrivateKey()));
// Get the plain text
Payload payload = jweObject.getPayload();
System.out.println(payload.toString());
return payload.toString();
}
private static RSAPublicKey getPublicKey() throws Exception {
String filename = "/home/vaibhav/Setups/cert/pub.der";
File f = new File(filename);
FileInputStream fis = new FileInputStream(f);
DataInputStream dis = new DataInputStream(fis);
byte[] keyBytes = new byte[(int)f.length()];
dis.readFully(keyBytes);
dis.close();
X509EncodedKeySpec spec = new X509EncodedKeySpec(keyBytes);
KeyFactory kf = KeyFactory.getInstance("RSA");
return (RSAPublicKey) kf.generatePublic(spec);
}
private static RSAPrivateKey getPrivateKey() throws Exception {
String filename = "/home/vaibhav/Setups/cert/private.pkcs8";
File f = new File(filename);
FileInputStream fis = new FileInputStream(f);
DataInputStream dis = new DataInputStream(fis);
byte[] keyBytes = new byte[(int)f.length()];
dis.readFully(keyBytes);
dis.close();
PKCS8EncodedKeySpec spec1 = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory kf = KeyFactory.getInstance("RSA");
return (RSAPrivateKey) kf.generatePrivate(spec1);
}