4

谁能给我一个在 BouncyCastle 中使用 GCM 和/或 CCM 模式与 AES 的示例？
我的代码是这样的： 

SecretKeySpec   key = new SecretKeySpec(keyBytes, "AES");
IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
Cipher          cipher = Cipher.getInstance("AES/GCM/NoPadding", "BC");
byte[] block = new byte[1048576];
int i;
long st,et;

cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);

BufferedInputStream bIn=new BufferedInputStream(new ProgressMonitorInputStream(null,"Encrypting ...",new FileInputStream("input")));
CipherInputStream       cIn = new CipherInputStream(bIn, cipher);
BufferedOutputStream bOut=new BufferedOutputStream(new FileOutputStream("output.enc"));

int ch;
while ((i = cIn.read(block)) != -1) {
    bOut.write(block, 0, i);
}
cIn.close();
bOut.close();

Thread.sleep(5000);

cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);

BufferedInputStream fis=new BufferedInputStream(new ProgressMonitorInputStream(null,"Decrypting ...",new FileInputStream("output.enc")));
//FileInputStream fis=new FileInputStream("output.enc");
//FileOutputStream ro=new FileOutputStream("regen.plain");
BufferedOutputStream ro=new BufferedOutputStream(new FileOutputStream("regen.plain"));

CipherInputStream dcIn = new CipherInputStream(fis, cipher);

while ((i = dcIn.read(block)) != -1) {
        ro.write(block, 0, i);
}

dcIn.close();
ro.close();

但在 GCM 模式下解密时会引发此异常（第 70 行是bOut.write(block, 0, i);）： 

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
    at java.lang.System.arraycopy(Native Method)
    at org.bouncycastle.crypto.modes.CCMBlockCipher.processPacket(Unknown Source)
    at org.bouncycastle.crypto.modes.CCMBlockCipher.doFinal(Unknown Source)
    at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher$AEADGenericBlockCipher.doFinal(Unknown Source)
    at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher.engineDoFinal(Unknown Source)
    at javax.crypto.Cipher.doFinal(DashoA13*..)
    at javax.crypto.CipherInputStream.a(DashoA13*..)
    at javax.crypto.CipherInputStream.read(DashoA13*..)
    at javax.crypto.CipherInputStream.read(DashoA13*..)
    at enctest.Main.main(Main.java:70)

在 CCM 模式下加密时出现此异常（第 70 行是bOut.write(block, 0, i);）： 

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
    at java.lang.System.arraycopy(Native Method)
    at org.bouncycastle.crypto.modes.CCMBlockCipher.processPacket(Unknown Source)
    at org.bouncycastle.crypto.modes.CCMBlockCipher.doFinal(Unknown Source)
    at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher$AEADGenericBlockCipher.doFinal(Unknown Source)
    at org.bouncycastle.jcajce.provider.symmetric.util.BaseBlockCipher.engineDoFinal(Unknown Source)
    at javax.crypto.Cipher.doFinal(DashoA13*..)
    at javax.crypto.CipherInputStream.a(DashoA13*..)
    at javax.crypto.CipherInputStream.read(DashoA13*..)
    at javax.crypto.CipherInputStream.read(DashoA13*..)
    at enctest.Main.main(Main.java:70)
4

1 回答 1

6

对于 CCM 模式有一个小问题：IV 的大小应该小于块大小。您的代码在以下情况下崩溃：

BlockCipher ctrCipher = new SICBlockCipher(cipher);
byte[] iv = new byte[blockSize];
byte[] out;

iv[0] = (byte)(((15 - nonce.length) - 1) & 0x7);

System.arraycopy(nonce, 0, iv, 1, nonce.length);

尝试使用 15 字节的“IV”代替（IV 实际上是一个 NONCE，但IvParameterSpec用于 NONCE）。

另一个问题是，当无法从底层流中检索任何数据时以及何时调用该cipher.doFinal()方法时，都会调用该方法。请注意，这是一个写得非常糟糕的类，当它被抛出时也会被删除 - 这是标签验证失败时出现的异常（！！！）。您最好创建自己的基于. 我已更改代码以引发特定的基于异常而不是忽略异常，并保持状态以查看是否已在基础密码上执行。它不应该调用两次。CipherInputStreamclose()CipherInputStreamBadPaddingExceptionCipherInputStreamIOExceptionbooleandoFinal()doFinal()

因此，您在这里运行的是 Java JCE 错误。我可能会将它放在 Oracle 错误数据库中，直到现在我的所有错误报告都被完全忽略了。

针对最新版本的 OpenJDK 7 和 Bouncy Castle 1.47（2012-08-30 或类似版本）进行了测试。

于 2012-09-02T12:21:54.417 回答