public static String doGenerate() {
int val = 10000000;
Random r = new Random();
int gen = r.nextInt(89999999);
int gen1 = r.nextInt(89999999);
gen = val + gen;
gen1 = val + gen1;
String reply = gen + "" + gen1;
return reply;
}
这是我用来生成下面给出的AES算法所需的密钥的方法。
public static void decryptFile(String keyString, String fileName){
try {
KeyGenerator kgen = KeyGenerator.getInstance("AES");
kgen.init(128);
SecretKey key = (SecretKey) new SecretKeySpec(
keyString.getBytes(), "AES");// kgen.generateKey();
AESEncrypter encrypter = new AESEncrypter(key);
encrypter.decrypt(new FileInputStream(
new java.io.File("").getCanonicalFile() +
File.separator + "Received"+
File.separator + fileName),
new FileOutputStream(new java.io.File("").getCanonicalFile() +
File.separator + "Decrypted" +
File.separator + fileName));
} catch (Exception e) {
e.printStackTrace();
}
}
这是AESEncrypter方法。
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();
}
}
解密后,我得到一个无效的密钥异常:java.security.InvalidKeyException:无效的AES密钥长度:64字节。为什么会这样?有解决方案吗?
答案 0 :(得分:1)
您的密钥生成功能存在缺陷 - 它只生成整数并将其转换为字符串,大大减少了可用的密钥空间并显着削弱了密钥。
但是,它确实产生了适合AES密钥的16字节值。我只能假设您上次收到错误消息后已更改了代码?
我强烈建议您恢复使用KeyGenerator
来生成AES密钥。这将以安全的方式实现。