Question

任何人都可以举例说明在BouncyCastle中使用带有AES的GCM和/或CCM模式吗？
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模式下解密时会抛出此异常（第70行为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行为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)

Answer 1

对于CCM模式，有一点障碍：IV的大小应小于块大小。您的代码在以下内容崩溃：

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”（IV实际上是NONCE，但IvParameterSpec用于NONCE）。

另一个问题是，当cipher.doFinal()无法从基础流中检索任何数据时，以及调用CipherInputStream时，都会调用close()方法。请注意，CipherInputStream是一个编写得非常糟糕的类，它在抛出时也会删除BadPaddingException - 这是标记验证失败时获得的异常（!!!）。您最好根据CipherInputStream创建自己的一个。我已经更改为代码以抛出特定的基于IOException的异常而不是忽略异常，并保持boolean状态以查看是否已在基础密码上执行doFinal()。它不应该两次调用doFinal()。

所以你在这里运行Java JCE错误。我可能会把它放在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。

测试最新版本的OpenJDK 7和Bouncy Castle 1.47（2012-08-30或接近结束）。

BouncyCastle GCM / CCM ArrayIndexOutOfBoundsException

1 个答案: