我真的无法自己解决这个问题,所以请帮帮我。这是一个使用 128 位 AES 加密现有文件 keeper.txt 内容的程序,将加密文本放入新创建的名为 Encrypted.txt 的文件中,然后将 Encrypted.txt 的内容解密为新创建的名为 Decrypted.txt 的文件
每次运行此程序时,它都会为加密生成一个随机密钥。
我只是想弄清楚我是否必须给某人 Encrypted.txt 文件,以及他以后如何使用此代码或稍微修改此代码来解密该文件。
我认为不可能将这个程序生成的密钥发送给他.. 是吗?因为当我尝试使用 system.out 打印密钥时,它没有给出密钥。
请帮帮我
package org.temp2.cod1;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import java.security.spec.AlgorithmParameterSpec;
public class AESEncrypter
{
Cipher ecipher;
Cipher dcipher;
public AESEncrypter(SecretKey key)
{
// Create an 8-byte initialization vector
byte[] iv = new byte[]
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
};
AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv);
try
{
ecipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// CBC requires an initialization vector
ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
}
catch (Exception e)
{
e.printStackTrace();
}
}
// Buffer used to transport the bytes from one stream to another
byte[] buf = new byte[1024];
public void encrypt(InputStream in, OutputStream out)
{
try
{
// Bytes written to out will be encrypted
out = new CipherOutputStream(out, ecipher);
// Read in the cleartext bytes and write to out to encrypt
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e)
{
}
}
public void decrypt(InputStream in, OutputStream out)
{
try
{
// Bytes read from in will be decrypted
in = new CipherInputStream(in, dcipher);
// Read in the decrypted bytes and write the cleartext to out
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e)
{
}
}
public static void main(String args[])
{
try
{
// Generate a temporary key. In practice, you would save this key.
// See also e464 Encrypting with DES Using a Pass Phrase.
KeyGenerator kgen = KeyGenerator.getInstance("AES");
kgen.init(128);
SecretKey key = kgen.generateKey();
// Create encrypter/decrypter class
AESEncrypter encrypter = new AESEncrypter(key);
// Encrypt
encrypter.encrypt(new FileInputStream("C:\\keeper.txt"),new FileOutputStream("C:\\Encrypted.txt"));
// Decrypt
encrypter.decrypt(new FileInputStream("C:\\Encrypted.txt"),new FileOutputStream("C:\\Decrypted.txt"));
}
catch (Exception e)
{
e.printStackTrace();
}
}
}