You're using a key of zero length, which is not valid for AES. The cipher
object will throw an exception, and since you're not catching it, the
program terminates. Please do provide backtraces in the future.
On Tue, Oct 08, 2002 at 06:19:19PM -0400, J Smith wrote:
>
> The exact error is a SIGABRT, which is being spit out of libstdc++. I can
> provide a backtrace if you'd like. I'm running a Linux system with gcc 2.96,
> a 2.4.18 kernel and glibc 2.2.4.
>
> Here's essentially the stripped-down code for what I'm doing, minus all of the
> nicities. It worked with Crypto++ 4.2, which is what my earlier PHP extension
> is based on. Basically, I end up with a bunch of classes derived from MyBase,
> and each can return a BlockTransformation via getEncryptionObject(), which
> MyBase::encrypt() uses for whatever purpose. This will produce the ABORT
> signal upon execution.
>
> ---------------
> #include <iostream>
> #include <cstdlib>
>
> #include "cryptlib.h"
> #include "aes.h"
>
> using namespace CryptoPP;
>
> class MyBase
> {
> public:
> bool encrypt();
> virtual BlockTransformation* getEncryptionObject() = 0;
> string itsPlaintext;
> string itsKey;
> string itsCiphertext;
> };
>
> bool MyBase::encrypt()
> {
> // as near as I can tell, this line causes the core dump...
> BlockTransformation* bt = getEncryptionObject();
>
> // after we have the BlockTransformation, we can use it
> // with CBC_Mode_ExternalCipher, ECB_Mode_ExternalCipher, etc.
> // Won't bother with that, as we've already core dumped by now.
>
> return true;
> }
>
> class MyAES : public MyBase
> {
> public:
> BlockTransformation* getEncryptionObject();
> };
>
> BlockTransformation* MyAES::getEncryptionObject()
> {
> return new AESEncryption((byte*) itsKey.data(), itsKey.length());
> }
>
>
> int main()
> {
> MyAES myaes;
> myaes.itsPlaintext = "this is some plaintext";
> myaes.itsKey = "this is a secret key";
> myaes.encrypt();
>
> return EXIT_SUCCESS;
> }
>
> ------------------
>
> The full code is a bit more expansive, naturally, but this reproduces the
> crash.
>
> Any ideas?
>
> Thanks again.
>
> J
>
>
>
>
>
> On October 8, 2002 03:35 pm, Wei Dai wrote:
> > On Tue, Oct 08, 2002 at 12:25:24PM -0400, J Smith wrote:
> > > BlockTransformation* bt = getEncryptionObject();
> > >
> > > The getEncryptionObject() method being implemented in some class thusly:
> > >
> > > BlockTransformation* MyAESClass::getEncryptionObject()
> > > {
> > > return new AESEncryption((byte*) itsKey, itsKeylength);
> > > }
> >
> > This code should still work. What error are you getting exactly?
> >
> > > Once I had bt set to a BlockTransformation (in this case, an
> > > AESEncryption object), I would hand it off to another method that would
> > > implement CBCPaddedEncryptor or CBC_CTS_Encryptor or some ECB
> > > implementation.
> >
> > Instead of CBCPaddedEncryptor, you now use CBC_Mode_ExternalCipher and
> > optionally StreamTransformationFilter.
